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Concentrations of total mercury, total selenium, and cadmium ([THg], [TSe], [Cd]) were determined in hair of California sea lion (Zalophus californianus) pups from four islands of the Gulf of California and the Baja California Pacific coast (NG, CG, NP, and CP) to identify geographical differences and the effect of Se against Hg toxicity (TSe:THg molar ratio). THg displayed a strong north-south trend for both ecoregions, while TSe presented a significantly high concentration only for CG. TSe:THg molar ratios decreased when [THg] increased, with the lowest ratios presenting in NG pups, in which [THg] exceeded toxicological thresholds of concern. [Cd] presented similar values at all study sites except CG, which presented the lowest level. The present study shows that proximity to urbanized coastal areas has a strong influence on [THg] in pups, while [TSe] and [Cd] are probably more related to the physiological requirements of the species, and environmental conditions.

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BACKGROUND & OBJECTIVES: Trypanosoma cruzi and Leishmania spp. are protozoans that cause American trypanosomiasis and leishmaniasis, respectively. In endemic foci where both diseases coincide, coinfection can occur. The objective of this work was the characterization of the parasites involved in coinfection in several endemic areas of Venezuela. METHODS: Molecular characterization was done in 30 samples of several species of mammals (Didelphis marsupialis, Equus mulus, Rattus rattus, Canis familiaris, Felis catus, and Sciurus granatensis) from the states of Anzoategui, Cojedes and Capital District diagnosed with T. cruzi and Leishmania spp. coinfections. For the typing of T. cruzi DTUs, the markers of miniexon, 24Sa rDNA, 18Sa rDNA, and hsp60-PCR-RFLP (EcoRV) were used. Infection by Leishmania spp. was characterized by miniexon multiplex PCR for complexes of Leishmania and ITS1-PCR-RFLP (HaeIII, HhaI, and RsaI) for the identification of the species. RESULTS: The T. cruzi TcI was present in 100% of the coinfected mammals, which included 76.7% of triple infection by T. cruzi TcI-complex-L. (L) mexicana-L. infantum/chagasi, 13.3% of double infection by T. cruzi TcI-L. mexicana and 10% of double infection by T. cruzi Tcl-L. infantum/chagasi. INTERPRETATION & CONCLUSION: These results suggest that the double or triple infection is a phenomenon existing in almost all the coendemics areas and mammals studied, which might influence the mechanisms of adaptation and pathogenicity of these parasites.

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Dinoflagellate algal blooms (DABs), with Lingulodinium polyedrum as the dominant species, have increased over the past few years in coastal areas off Baja California, Mexico. Vertical and temporal variability of particulate cadmium (Cdp), dissolved Cd (Cdd), PO4(3-) and Cdd/PO4(3-) were investigated during two intense DABs of L. polyedrum that occurred during the fall of 2011 and 2012 in Todos Santos Bay. Results were then, compared with data gathered in the absence of algal blooms during the autumn of 2013. In both algal blooms, L. polyedrum tended to be concentrated near the surface throughout the duration; however, during DAB 2011 the number of cells was twice as abundant ([10.0 ± 8.0] × 10(5) cells L(-1)) as in DAB 2012 ([5.0 ± 4.4] × 10(5) cells L(-1)). During DAB 2011, Cdp increased significantly (up to 1.02 ± 0.99 nmol kg(-1)) and was positively correlated with the cell abundance of L. polyedrum, suggesting that this dinoflagellate is able to assimilate and concentrate Cdd. Likewise, Cdd (up to 0.71 ± 0.17 nM) increased in the days of highest cell abundance, which could be attributed to uptake and subsequent regeneration of Cdd resulting from the remineralization of organic particulate matter produced during the bloom, as well as with the presence of organic ligands secreted by L. polyedrum that could keep Cdd in solution. During DAB 2011, dissolved Cdd/PO4(3-) ratios exhibited high vertical and temporal variability in the upper 5 m of the water column, but remained virtually constant near the bottom, suggesting a depth-dependent decoupling between these two dissolved components during the bloom development. Given the observed differences in the vertical and temporal variability of Cdd, Cdp, and PO4(3-) between these two intense DABs, we propose the existence of an abundance threshold of approximately 10(6) cells L(-1) of L. polyedrum above which Cd and PO4(3-) significantly increased due to remineralization in coastal waters during the bloom development.

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Schistosomiasis is a disease caused by parasitic flatworms of the genus Schistosoma, whose diagnosis has limitations, such as the low sensitivity and specificity of parasitological and immunological methods, respectively. In the present study an alternative molecular technique requiring previous standardization was carried out using the polymerase chain reaction (PCR) for the amplification of a 121-bp highly repetitive sequence for Schistosoma mansoni. DNA was extracted from eggs of S. mansoni by salting out. Different conditions were standardized for the PCR technique, including the concentration of reagents and the DNA template, annealing temperature and number of cycles, followed by the determination of the analytical sensitivity and specificity of the technique. Furthermore, the standardized PCR technique was employed in DNA extracted, using Chelex®100, from samples of sera of patients with an immunodiagnosis of schistosomiasis. The optimal conditions for the PCR were 2.5 mm MgCl2, 150 mm deoxynucleoside triphosphates (dNTPs), 0.4 µm primers, 0.75 U DNA polymerase, using 35 cycles and an annealing temperature of 63°C. The analytical sensitivity of the PCR was 10 attograms of DNA and the specificity was 100%. The DNA sequence was successfully detected in the sera of two patients, demonstrating schistosomiasis transmission, although low, in the community studied. The standardized PCR technique, using smaller amounts of reagents than in the original protocol, is highly sensitive and specific for the detection of DNA from S. mansoni and could be an important tool for diagnosis in areas of low endemicity.

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Introducción: Los catéteres venosos centrales (CVC) plantean un alto riesgo de infección. La infección del sitio de salida (ISS-CVC) es la menos estudiada, y se desconoce su asociación con la bacteriemia asociada a catéter (BAC) y su impacto en la evolución del paciente. Objetivo: Evaluar la asociación entre ISS-CVC, BAC y mortalidad. Materiales y métodos: Estudio prospectivo, de observación. Pacientes internados en una Unidad de Terapia Intensiva médico/quirúrgica que requirieron la colocación de CVC desde el 01/06/2010 hasta el 01/04/2012. Se evaluaron datos epidemiológicos, BAC (según criterios de los CDC) y gérmenes. Se utilizaron media ± DE, mediana y rango intercuartílico, y porcentajes. Resultados: Durante este período, ingresaron 575 pacientes, el 98% requirió CVC. Datos de los pacientes: edad 41 ± 26 años, APACHE II 15 ± 7, 96% con ventilación mecánica, días de ventilación mecánica 41 (33-63), días de internación 43 (25-67). Todos los CVC con ISS fueron retirados y cultivados. Se observaron 51 ISS: 5,5/1000-días-catéter: 33% subclavia, 38% yugular, 29% femoral. Seis pacientes con ISS (12%) tuvieron BAC (0,65/1000-días-catéter): 3 subclavias, 2 yugulares, 1 femoral; 2 con halo y 8 con secreción purulenta. Tiempo de permanencia del CVC: 7,5 días (5-10). Clínica al momento de la ISS: shock 50%, fiebre 83%, SOFA 6 ± 3. El 83% de las infecciones fueron monomicrobianas: 83% por bacilos gramnegativos (2 Klebsiella, 2 Pseudomonas, 1 Serratia y 1 Acinetobacter), 17% por enterococos resistentes a vancomicina. La mortalidad fue del 50%. Conclusión: Aunque la ISS provocó una baja incidencia de BAC, la mortalidad fue alta. Al parecer, la ISS no es un factor predictivo de BAC.(AU)

Introduction: Central venous catheters (CVC) are widely used and pose a high risk of infection. There are few studies on insertion site infection (ISI-CVC), and both its association with catheter-associated bloodstream infection (CABSI) and the outcome of patients are unknown. Objective: To determine the association between ISI-CVC, the presence of CABSI and mortality. Materials and methods: Prospective observational study. All patients admitted to a medical/surgical Intensive Care Unit requiring CVC insertion from 06/01/2010 to 04/01/2012 were included. Epidemiological data, CABSI (according to CDC criteria) and microorganisms involved were evaluated. Mean ± SD, median and interquartile range, and percentages were used. Results: During the period study, 575 patients were admitted, 98% required CVC. Patient´s data: age 41 ± 26 years, APACHE II 15 ± 7, 96% on mechanical ventilation, days on mechanical ventilation: 41 (33-63), length of stay 43 (25-67) days. All CVCs with ISI were removed and cultured. Fifty one ISI were observed (5.5/1000-catheter-day). Six patients with ISI (12%) presented CABSI (0.65/1000-catheter-day): 3 in subclavian, 2 in jugular, 1 femoral; 2 with erythema and 8 with purulent secretion. CVC permanence: 7.5 day (5-10). Signs and/or symptoms at the moment of ISI: shock 50%, fever 83%, SOFA 6 ± 3. The 83% of infections were caused by one microorganism: 83% due to gram-negative bacilli (2 Klebsiella, 2 Pseudomonas, 1 Serratia, and 1 Acinetobacter), 17% due to vancomycin-resistant enterococci. The mortality rate was 50%. Conclusion: Although ISI-CVC presented a low incidence of CABSI, mortality rate was high. The ISI-CVC might have a little predictable value for CABSI.(AU)

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Mercury and arsenic levels in muscle and liver of Rhinoptera steindachneri were determined in organisms collected in 2006. Element concentrations in both tissues were directly related to size. Maxima mean concentrations of Hg and As (0.41 and 59.9 microg g(-1) dry wt, respectively) were found in adults muscle. Mercury concentrations were significantly different between juveniles and adults in muscle and liver. For As concentrations, differences between juveniles and adults were found only in muscle. Mercury concentrations were higher in muscle of juveniles and adults. Arsenic concentrations were higher in liver of juveniles, and in muscle of adults. Maximum Hg concentration in muscle (0.65 microg g(-1) dry wt) was below the safe limit established by Mexican regulations for seafood.

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Dissolved and particulate metals (Ag, Cd, Co, Cu, Ni, and Zn) and nutrients (PO(4), NO(3), and H(4)SiO(4)) were measured in Todos Santos Bay (TSB) in August 2005. Two sources producing local gradients were identified: one from a dredge discharge area (DDA) and another south of the port and a creek. The average concentrations of dissolved Cd and Zn (1.3 and 15.6 nM, respectively) were higher by one order of magnitude than the surrounding Pacific waters, even during upwelling, and it is attributed to the presence of a widespread and long-lasting red tide coupled with some degree of local pollution. A clear spatial gradient (10 to 6 pM), from coast to offshore, of dissolved Ag was evident, indicating the influence of anthropogenic inputs. The particulate fraction of all metals, except Cu, showed a factor of ~3 decrease in concentrations from the DDA to the interior of the bay. The metal distributions were related to the bay's circulation by means of a numerical model that shows a basically surface-wind-driven offshore current with subsurface compensation currents toward the coast. Additionally, the model shows strong vertical currents over the DDA. Principal component analysis revealed three possible processes that could be influencing the metal concentrations within TSB: anthropogenic inputs (Cd, Ag, and Co), biological proceses (NO(3), Zn, and Cu), and upwelling and mixing (PO(4), H(4)SiO(4), Cd, and Ni). The most striking finding of this study was the extremely high Cd concentrations, which have been only reported in highly contaminated areas. As there was a strong red tide, it is hypothesized that the dinoflagellates are assimilating the Cd, which is rapidly remineralized and being concentrated on the stratified surface layers.

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El presente estudio se realizó con la finalidad de determinar si la Dipirona altera la agregación plaquetaria. Para ello, se seleccionaron 30 voluntarios sanos, los cuales fueron divididos en dos grupos y asignados al azar a recibir 1 g de Dipirona o 100 mg de Acido Acetilsalicílico. Se determinó la agregación plaquetaria a través del método turbidimétrico; utilizando adenosin difosfato, colágeno y adrenalina. En el grupo Dipirona, se observó una reducción estadísticamente significativa de la agregación plaquetaria a las 72 horas, frente a los 3 estímulos; que revirtió a las 24 horas. En el grupo Acido Acetilsalicílico, disminuyó significativamente la agregación plaquetaria a las 24 horas. Al comparar ambos grupos no hubo diferencia significativa en la muestra basal pero si a las 24 horas. Podemos concluir que la Dipirona, al igual que el resto de los antiinflamatorios no esteroideos, inhibe la agregación plaquetaria de forma reversible, al contrario del Acido Acetilsalicílico.

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The soft tissue of Mytilus californianus has the capacity to decrease its Cd concentration in the order of days. However, for medium-term (months) pollution surveys it is necessary to find alternative structures capable of integrating Cd concentrations during longer periods of time. The recently deposited nacreous layer of the shell of M. californianus is proposed as such a structure. Daily variability of Cd concentration in the soft tissue and in the recently deposited nacreous layer of a natural population of mussels was compared during a period of 26 days in organisms collected from an upwelling zone of British Columbia. Statistical analysis of the Cd concentrations indicated that the nacreous layer presented less significant differences between days than the associated soft tissue. Only one shell sample showed significant differences in Cd concentrations, probably related to environmental conditions and stress arising from mussel population density. Experimental results carried out in the laboratory confirmed that the recently deposited nacreous layer of M. californianus is a better medium-term indicator of Cd in seawater, especially at low concentration exposures of this element, those similar to the ones encountered in natural environments.

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La lipemia posprandial se refiere a un incremento exagerado en plasma de las concentraciones de triglicéridos consecuencia del aumento en el tiempo de residencia de estas lipoproteínas transportadoras, especialmente ricas en triglicéridos, por efectos de trastornos en su metabolismo. El objetivo del presente trabajo fue demostrar las variaciones del perfil lipídico posprandial, después de una comida rica en grasa y su relación con el IMC, antecedentes familiares, personales y la enfermedad arterial coronaria en dicha respuesta, en 190 pacientes, a los que se les realizó el perfil lipídico basal (colesterol, triglicéridos, HDL-C, LDL-C) con 14 horas de ayuno. Posteriormente se les suministró una comida con 100 gramos de grasa, y se les realizó una toma de muestra de sangre periférica a las 6 y 8 horas respectivamente. Se encontró que los individuos intolerantes y lipémicos se correlacionan positivamente con IMC > de 25, HTA y antecedentes personales y familiares para enfermedad arterial coronaria. La prueba de tolerancia de grasa es un estudio sencillo, fácil de realizar y un buen método para detectar pacientes de alto riesgo para enfermedad cardiovascular

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