Infectivity of Leishmania mexicana Is Associated with Differential Expression of Protein Kinase C-Like Triggered during a Cell-Cell Contact

Mammalian host cell invasion by Leishmania is a complex process in which various parasite and host cell components interact, triggering the activation of signaling cascades in both cells. Little is known regarding PKC biological functions in Leishmania sp. during parasite-macrophage interaction. PKC-like enzyme was first identified in homogenates and membrane fraction of L. mexicana stationary promastigotes by immunoblot. PKC-like enzyme activity was then detected in cell homogenates but also on intact promastigotes showing for the first time the presence of an ecto-PKC dependent on Ca2+/phosphatidylserine for activation. This ecto-PKC was activated with phorbol myristate acetate (PMA) and inhibited by RO-32-0432, a selective PKCαβIε bisindolylmaleimide inhibitor. Interestingly, the Leishmania PKC- activity was higher in the infective stationary than in non-infective logarithmic stage. Then, promastigotes at different stages of time proliferation curve were used in order to identify the role of PKC-like during macrophage invasion. After attachment to macrophages, PKC-like is over-expressed in promastigotes at the 6th culture day but also at the 4th day of culture corresponding to the maximal infection capacity. An antibody microarray for MAPK and PKC corroborate the Leishmania PKC-like over-expression during contact with macrophages. Pretreatment with RO-32-0432 inhibitor reduced the number of infected macrophages and the parasite burden. These data suggest for the first time a direct link between PKC expression level and infectivity, and provide evidence that PKC-like plays a critical role in attachment and in the internalization steps involved in the invasion process

Comparación de dos pruebas de aglutinación (Toxolatex ® y Toxoscreen ®) en el diagnóstico de la toxoplasmosis: propuesta de inclusión en un programa de control

This study evaluated a latex agglutination test (Toxolatex ®, Fumouze) and a direct agglutination test using a whole antigen (Toxoscreen ®, Biomerieux) for the screening of toxoplasmosis antibodies, by means of comparison with the dye test (Sabin Feldman) (DT) and a fluorescent antibody test (IFAT). On 500 sera, a good correlation was obtained for these methods with DT (TI 96.8% and TS 98.6%) and IFAT (TL 95.4% and TS 97.2%). In addition to detecting antitoxoplasma immunoglobulin M antibodies. TL is a rauid, easy and inexpensive technique. Based these findings, we recommend the agglutination testior initial screening of specific antibodies against toxoplasmosis in seroepidemiological surveys and pregnancy control program.Este estudio evaluó las pruebas de aglutinación en Iátex. Toxolatex ®. Furnouze (.T L). .v aglutinación directa. Toxoscreen ®, Biomerieux (TS), mediante la comparación con las pruebas de referencia: prueba de neutralización, dye test (DT) e inmunofluorescencia indirecta (IFI). En los 500 sueros estudiados, se encontró una buena concordancia entre las técnicas estudiadas y las de referencia asi: DT (TI, 963% y TS. 98.6%) e IFI (TI 95,4% y TS 97.2%) El TL, además de detectar anticuerpos de clase IgM antitoxoplasma, es una técnica poco costosa y de fácil y rápida realización. Los resultados de este estudio permiten recomendar las pruebas de aglutinación para el tamizaje de anticuerpos especificas antitoxoplasma en los programas de control prenatal y en los estudios seroepidemiológicos

Bloom-forming cyanobacteria and dinoflagellates in five Argentinian reservoirs: Multi-year sampling

Harmful algal blooms are important threats to reservoir condition. Over a 15-year period, we sampled fiveArgentinian reservoirs to identify the responsible species for harmful algal blooms and determine the waterquality factors driving their occurrence. These reservoirs exhibit diverse morphological and hydrological characteristics and are distributed across varying climatic zones. Cyanobacterial blooms included an array of species,including toxin producers such as Raphidiopsis raciborskii, Aphanizomenon gracile, and Microcystis aeruginosa. Incontrast, dinoflagellate blooms were predominantly characterized by Ceratium. The cyanobacterial blooms primarily occurred in the shallower reservoirs located in warmer regions, whereas dinoflagellate blooms occurredwhere temperatures were lower. The most intense blooms occurred during the summer, and although cyanobacterial and chlorophyte blooms co-occurred, they never coexisted with dinoflagellate blooms. We identifiedcyanotoxins in the reservoirs over the past three years, a phenomenon previously unreported in the region. Giventhat these reservoirs are drinking water sources for human populations, ongoing and systematic monitoring isneeded to protect public health. Controlling the proliferation of algae and cyanobacteria in reservoirs requiresresource management at the watershed level, and in the case of the Itiyuro and El Limon, requires binational management with Bolivia.Fil: Alvarez Dalinger, Florencia Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Salta; ArgentinaFil: Borja, Claudia Nidia. Universidad Nacional de Salta. Facultad de Cs.naturales. Catedra Biologia y Diversidad de Protistas Autotrofos y Fungi.; ArgentinaFil: Lozano, Verónica Laura. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Salta; ArgentinaFil: Moraña, Liliana Beatriz. Universidad Nacional de Salta. Facultad de Cs.naturales. Catedra Biologia y Diversidad de Protistas Autotrofos y Fungi.; ArgentinaFil: Salusso, Maria Monica. Universidad Nacional de Salta. Facultad de Cs.naturales. Catedra Biologia y Diversidad de Protistas Autotrofos y Fungi.; Argentin

Ambulatory postural blood pressure changes and history allow a better selection of patients that should undergo a head-up tilt test

Background: Syncope is a common symptom and in most cases it is of a neurally mediated origin. Such patients have to be studied with a careful history and a physical exploration that should include simple maneuvers such as blood pressure (BP) recordings in decubitus and standing position. These tools can suggest diagnosis in a good percentage of patients without the need for expensive or invasive testing. Methods: We carried out a prospective observational study measuring BP and heart rate (HR) with the patients in decubitus and just as they stood up. The patients were sent for a tilt table test in different specialized centers. The BP changes were compared to the results of the tilt test. Results: We included 215 patients, 36.1 ± 18.8 years old, 118 (54.9%) feminine, of which 143 (66.5%) had a positive tilt test. Patients with a positive test showed a rise in systolic BP (SBP) (121.7 ± 19.1 vs. 124.2 ± 20, p < 0.005) and in diastolic BP (DBP) (75 ± 11 vs. 78 ± 11.3, p < 0.005) when compared to people with a negative one. On the other hand, per­centage BP changes were significantly different (SBP 2.24% vs. 0.48%, p = 0.02; DBP 4.1% vs. 1.2%, p = 0.009). Patients with a positive test had also a lower HR on standing up (72.1 ± ± 11.1 vs. 78.3 ± 17.2, p = 0.01). Conclusions: Patients with neurally mediated syncope showed an elevation of SBP and DBP when standing up actively, unlike subjects with a negative tilt test

Soybean Seed Compounds as Natural Health Protectors

Glycine max (L) Merrill, better known as soy or soybean, is a legume of asian origin considered an excellent biotype, given the fact that it contains almost everything the human being needs for the diet. Its cultivation worldwide is one of the most important, and soy itself and its derivatives are highly on demand. The health effects of soy derived foods have been investigated for more than 25 years, and some of them remain controversial. On the other hand, we wondered if soy could be used to ameliorate the toxic effects of heavy metals. Therefore, in this chapter we review general characteristics of soy as well as its nutritional potential, and we compiled the newest information about the health effects of soy. In order to test our hypothesis, we developed a model of animals exposed to cadmium, and we gave them a soy based diet, comparing it with a casein-based diet as control. This allowed us to collect information about its effect on the respiratory and nervous system. Among the results of this review, we show that it reduces the cholesterol level and obesity while also having antidiabetic effects. We enumerate the benefits of soy-based diets on the respiratory system, such as protection against lung cancer and radiotherapy, better lung function in asthma patients and protection against cadmium intoxication. In the cardiovascular system it reduces the risk of coronary heart disease, improves blood pressure, glycemic control, and inflammation while it reduces not all but some of the alterations induced by cadmium exposure on the aorta and heart. It apparently promotes neurogenesis, improves cognitive functions, and reduces the oxidative stress and apoptosis induced by cadmium exposure in the cerebellum. Taken all together, this information let us conclude that soy consumption would exhibit numerous benefits for human health, although future studies should try to elucidate the best outcome considering variables such as gender, age, treatment duration and dosage of soy products consumption in the diet

First Human Model of In Vitro Candida albicans Persistence within Granuloma for the Reliable Study of Host-Fungi Interactions

BACKGROUND: The balance between human innate immune system and Candida albicans virulence signaling mechanisms ultimately dictates the outcome of fungal invasiveness and its pathology. To better understand the pathophysiology and to identify fungal virulence-associated factors in the context of persistence in humans, complex models are indispensable. Although fungal virulence factors have been extensively studied in vitro and in vivo using different immune cell subsets and cell lines, it is unclear how C. albicans survives inside complex tissue granulomas. METHODOLOGY/PRINCIPAL FINDING: We developed an original model of in vitro human granuloma, reproducing the natural granulomatous response to C. albicans. Persistent granulomas were obtained when the ratio of phagocytes to fungi was high. This in vitro fungal granuloma mimics natural granulomas, with infected macrophages surrounded by helper and cytotoxic T lymphocytes. A small proportion of granulomas exhibited C. albicans hyphae. Histological and time-lapse analysis showed that C. albicans blastoconidia were located within the granulomas before hyphae formation. Using staining techniques, fungal load calculations, as well as confocal and scanning electron microscopy, we describe the kinetics of fungal granuloma formation. We provide the first direct evidence that C. albicans are not eliminated by immunocompetent cells inside in vitro human granulomas. In fact, after an initial candicidal period, the remaining yeast proliferate and persist under very complex immune responses. CONCLUSIONS/SIGNIFICANCE: Using an original in vitro model of human fungal granuloma, we herein present the evidence that C. albicans persist and grow into immunocompetent granulomatous structures. These results will guide us towards a better understanding of fungal invasiveness and, henceforth, will also help in the development of better strategies for its control in human physiological conditions

CCHD Screening Implementation Efforts in Latin American Countries by the Ibero American Society of Neonatology (SIBEN).

Congenital heart disease (CHD) is among the four most common causes of infant mortality in Latin America. Pulse oximetry screening (POS) is useful for early diagnosis and improved outcomes of critical CHD. Here, we describe POS implementation efforts in Latin American countries guided and/or coordinated by the Ibero American Society of Neonatology (SIBEN), as well as the unique challenges that are faced for universal implementation. SIBEN collaborates to improve the neonatal quality of care and outcomes. A few years ago, a Clinical Consensus on POS was finalized. Since then, we have participated in 12 Latin American countries to educate neonatal nurses and neonatologists on POS and to help with its implementation. The findings reveal that despite wide disparities in care that exist between and within countries, and the difficulties and challenges in implementing POS, significant progress has been made. We conclude that universal POS is not easy to implement in Latin America but, when executed, has not only been of significant value for babies with CHD, but also for many with other hypoxemic conditions. The successful and universal implementation of POS in the future is essential for reducing the mortality associated with CHD and other hypoxemic conditions and will ultimately lead to the survival of many more Latin American babies. POS saves newborns' lives in Latin America