A model for preservation of thymocyte-depleted thymus.

DiGeorge syndrome is a disorder caused by a microdeletion on the long arm of chromosome 22. Approximately 1% of patients diagnosed with DiGeorge syndrome may have an absence of a functional thymus, which characterizes the complete form of the syndrome. These patients require urgent treatment to reconstitute T cell immunity. Thymus transplantation is a promising investigational procedure for reconstitution of thymic function in infants with congenital athymia. Here, we demonstrate a possible optimization of the preparation of thymus slices for transplantation through prior depletion of thymocytes and leukocyte cell lineages followed by cryopreservation with cryoprotective media (5% dextran FP 40, 5% Me2SO, and 5% FBS) while preserving tissue architecture. Thymus fragments were stored in liquid nitrogen at -196°C for 30 days or one year. The tissue architecture of the fragments was preserved, including the distinction between medullary thymic epithelial cells (TECs), cortical TECs, and Hassall bodies. Moreover, depleted thymus fragments cryopreserved for one year were recolonized by intrathymic injections of 3×106 thymocytes per mL, demonstrating the capability of these fragments to support T cell development. Thus, this technique opens up the possibility of freezing and storing large volumes of thymus tissue for immediate transplantation into patients with DiGeorge syndrome or atypical (Omenn-like) phenotype.

A model for preservation of thymocyte-depleted thymus

DiGeorge syndrome is a disorder caused by a microdeletion on the long arm of chromosome 22. Approximately 1% of patients diagnosed with DiGeorge syndrome may have an absence of a functional thymus, which characterizes the complete form of the syndrome. These patients require urgent treatment to reconstitute T cell immunity. Thymus transplantation is a promising investigational procedure for reconstitution of thymic function in infants with congenital athymia. Here, we demonstrate a possible optimization of the preparation of thymus slices for transplantation through prior depletion of thymocytes and leukocyte cell lineages followed by cryopreservation with cryoprotective media (5% dextran FP 40, 5% Me2SO, and 5% FBS) while preserving tissue architecture. Thymus fragments were stored in liquid nitrogen at -196°C for 30 days or one year. The tissue architecture of the fragments was preserved, including the distinction between medullary thymic epithelial cells (TECs), cortical TECs, and Hassall bodies. Moreover, depleted thymus fragments cryopreserved for one year were recolonized by intrathymic injections of 3×106 thymocytes per mL, demonstrating the capability of these fragments to support T cell development. Thus, this technique opens up the possibility of freezing and storing large volumes of thymus tissue for immediate transplantation into patients with DiGeorge syndrome or atypical (Omenn-like) phenotype.

Beyond scoring systems: usefulness of morphometry considering demographic variables, to evaluate neck and overall obesity in Andalusian horses.

Morphometry has proven to be a useful tool, both for the clinician and horse owners, for evaluating the body condition in equids due to its objectivity, easiness and capacity for detection of important metabolic disturbances. However, limited information is available on the use of morphometric ratios to characterize regional and overall adiposity and much less about their application in different genders, ages and horses with different levels of obesity. The objectives were to evaluate body and neck absolute measurements and ratios; factors affecting them such as the influence of gender, age, appearance of the neck crest and overall body condition and; relationships among these measurements. A total of 154 Andalusian horses classified according to their gender, age, body score status and cresty neck condition were evaluated in this cross-sectional study. Two evaluators assigned a body condition score (BCS, 1 to 9) and a cresty neck score (CNS, 0 to 5) to each horse. Horses were divided into males and females; young (2 to 5 years) and adults (6 to 15 years); obese (BCS⩾7) and non-obese (BCS<7); cresty neck (CNS⩾3) and non-cresty neck horses (CNS<3). Morphometric measurements (cm) included were: height at the withers (HW); body length (BL), girth (GC) and waist (WC) circumferences; neck length (NL); three neck circumferences (NCs), over the first (NC25%), the second (NC50%) and the third part (NC75%) of the NL and neck crest height (NCH). These measurements were also used to calculate the following ratios: GC : HW, WC : HW, GC : BL, WC : BL, NC25% : HW, NC50% : HW, NC75% : HW, NC25% : BL, NC50% : BL, NC75% : BL, NC25% : NL, NC50% : NL, NC75% : NL, NC25% : NCH, NC50% : NCH and NC75% : NCH. The results showed that most of the absolute measurements and ratios were greater than those described in other light breeds. In addition, most neck ratios were higher (P<0.050) in males than in females, however, all body ratios were greater (P<0.001) in females. Among the absolute measurements, WC in obese horses and NC25% and NC75% in cresty neck horses highlighted as higher. Either GC : HW or WC : HW and NC75% : BL were alternative surrogates for the appraisal of overall and regional adiposity in Andalusians. Several interactions were observed between the gender and adiposity scoring systems affecting the morphometric evaluation. This study establishes absolute morphometric measurements and ratios in Andalusian horses. It also highlights the variability of morphometric values and how the outcome of these can be influenced by demographic variables and the breed analyzed. Further studies are necessary to set morphometric reference values in other breeds.

Self-fertilization, long-distance flash invasion and biogeography shape the population structure of Pseudosuccinea columella at the worldwide scale.

Population genetic studies are efficient for inferring the invasion history based on a comparison of native and invasive populations, especially when conducted at species scale. An expected outcome in invasive populations is variability loss, and this is especially true in self-fertilizing species. We here focus on the self-fertilizing Pseudosuccinea columella, an invasive hermaphroditic freshwater snail that has greatly expanded its geographic distribution and that acts as intermediate host of Fasciola hepatica, the causative agent of human and veterinary fasciolosis. We evaluated the distribution of genetic diversity at the largest geographic scale analysed to date in this species by surveying 80 populations collected during 16 years from 14 countries, using eight nuclear microsatellites and two mitochondrial genes. As expected, populations from North America, the putative origin area, were strongly structured by selfing and history and harboured much more genetic variability than invasive populations. We found high selfing rates (when it was possible to infer it), none-to-low genetic variability and strong population structure in most invasive populations. Strikingly, we found a unique genotype/haplotype in populations from eight invaded regions sampled all over the world. Moreover, snail populations resistant to infection by the parasite are genetically distinct from susceptible populations. Our results are compatible with repeated introductions in South America and flash worldwide invasion by this unique genotype/haplotype. Our study illustrates the population genetic consequences of biological invasion in a highly selfing species at very large geographic scale. We discuss how such a large-scale flash invasion may affect the spread of fasciolosis.

BLM germline and somatic PKMYT1 and AHCY mutations: Genetic variations beyond MYCN and prognosis in neuroblastoma.

Neuroblastoma (NB) is the most common extra cranial solid tumor of childhood and often lethal in childhood. Clinical and biologic characteristics that are independently prognostic of outcome in NB are currently used for risk stratification to optimally the therapy. It includes age at diagnosis, International Neuroblastoma Staging System tumor histopathology and MYCN amplification. However, even in patients with theoretically good prognosis, such as localized tumor and non-amplified MYCN, either disease progress or recurrence may occur. Potential genetic determinants of this unfavorable behavior are not yet fully clarified. The presence of elevated expression of AHCY, PKMYT1, and BLM has accompanied poor prognosis MYCN-amplified neuroblastoma patients. Considering the potential implication of these genes on the clinical management of NB, we hypothesize that the identification of genetic variations may have significant impact during development of the recurrent or progressive disease. Using targeted DNA sequencing, we analyzed the mutation profiles of the genes PKMYT1, AHCY, and BLM in tumor samples of five patients with MYCN amplified and 15 MYCN non-amplified NB. In our study, BLM germline variants were detected in two patients with MYCN-non-amplified neuroblastoma. Our data allow us to hypothesize that, regardless of MYCN status, these mutations partially abolish BLM protein activity by impairing its ATPase and helicase activities. BLM mutations are also clinically relevant because BLM plays an important role in DNA damage repair and the maintenance of genomic integrity. We also found a novel variant in our cohort, PKMYT1 mutation localized in the C-terminal domain with effect unknown on NB. We hypothesize that this variant may affect the catalytic activity of PKMYT1 in NB, specifically when CDK1 is complexed to cyclins. The prognostic value of this mutation must be further investigated. Another mutation identified was a nonsynonymous variant in AHCY. This variant may be related to the slow progression of the disease, even in more aggressive cases. It affects the maintenance of the catalytic capacity of AHCY, leading to the consequent functional effects observed in the NB patients studied. In conclusion, our hypothesis may provide that mutations in BLM, AHCY and PKMYT1 genes found in children with MYCN-amplified or MYCN-non amplified neuroblastomas, may be associated with the prognosis of the disease.

Endocrine, morphometric, and ultrasonographic characterization of neck adiposity in Andalusian horses.

Equine metabolic syndrome (EMS) can be diagnosed by hormonal measurements; however, it would be important to find simpler measurements that allow easy identification of affected or at risk individuals. In horses, the dorsal neck region is one of the most frequent anatomical sites for fat deposition and neck obesity has been linked to EMS. The aim of this study was to evaluate the association of hormonal markers of obesity (leptin) and insulin resistance (insulin) with morphometric and ultrasonographic neck measurements in Andalusian horses. Plasma leptin and insulin concentrations were measured by RIA in 127 Andalusian horses. Neck circumferences (NC) were measured at 3 equidistant locations at 25%, 50%, and 75% of neck length (NC-25%, NC-50%, and NC-75%). At the same 3 locations, subcutaneous fat thickness (SFT-25%, SFT-50%, and SFT-75%) was measured ultrasonographically. In the population under study, a tendency to adiposity was confirmed by the elevated plasma leptin levels (7.47 ± 5.03 ng/mL). However, plasma insulin concentrations (4.05 ± 3.74 µIU/mL) were within normal range in most horses. Our results indicate that NC showed significant sexual dimorphism and did not correlate well with hormonal measurements. Ultrasonographic assessment of fat thickness at the base of the neck (SFT-75%) was significantly correlated with both plasma leptin and insulin and did not show differences between males and females. Thus, in the search for a single objective parameter which can be used in large populations, SFT-75% is a potential candidate and may be a meaningful parameter to predict EMS.

Clinical Research Abstracts of the British Equine Veterinary Association Congress 2015.

REASONS FOR PERFORMING STUDY: Andalusian horses have been proposed as a breed predisposed to equine metabolic syndrome (EMS) phenotype [1] because they are prone to exhibiting regional, generalised adiposity and tendency to laminitis [2]. Insulin dysregulation represents the main pathophysiological cause for all the features of EMS, however there are no epidemiological studies in this breed. OBJECTIVE: To assess insulin dysregulation through insulin proxies in Andalusian horses with different levels of obesity. STUDY DESIGN: Cross-sectional study. METHODS: One hundred and sixty-four Andalusians (78 stallions and 86 mares, 2-15 years) were scored for overall (body condition score, BCS) and neck (cresty neck score, CNS) adiposity. Grain concentrate was withheld for 12 h before sampling. Blood samples were collected between 06.00-10.00 h for basal glucose, insulin concentrations, RISQI and MIRG proxies calculation. Conditions were defined as: obese horses (Ob), BCS ≥ 7; cresty neck horses (CN), CNS ≥ 3; hyperinsulinaemia, insulin ≥20 µu/ml; low insulin sensitivity, RISQI<0.32[mu/l](-0.5) and increased insulin secretory response, MIRG>5.6muinsulin (2)/[10.l.mgglucose]. Regarding BCS 2 groups were created: Ob and non-Ob. These groups were subdivided depending on CNS: with CN and without it (nonCN). Ob-nonCN group (n = 2) was excluded for the statistics due to the low number of horses. RESULTS: Of the horses studied, 26.8% were Ob-CN, 42.1% were nonOb-CN and 31.1% were nonOb-nonCN. Ob horses presented higher insulin levels (P = 0.034) and lower RISQI values (P = 0.019) than all nonOb horses. When CN was considered, only RISQI was lower (P = 0.015) in Ob-CN group respect to nonOb-nonCN, however nonOb-CN group does not differ from the other 2 groups. Furthermore, the percentage of Ob-CN horses with hyperinsulinaemia (2.3%), abnormal RISQI (4.5%) and MIRG (9.1%) was very low. CONCLUSIONS: These results suggest that in Andalusians, increased adiposity was not clearly associated to insulin dysregulation and, similar to human beings, may coexist as a metabolically healthy but obese phenotype. Ethical animal research: Ethical University Committee approved all the procedures and owner informed consent was obtained. SOURCE OF FUNDING: None. Competing interests: None declared.

Visual Inspection for Caries Detection: A Systematic Review and Meta-analysis.

We aimed to perform a systematic review including a meta-analysis to evaluate the overall accuracy of visual methods for detecting carious lesions and to identify possible sources of heterogeneity among the studies included. Two reviewers searched PubMed, Embase, Scopus, and other sources through July 2014 to identify published and nonpublished studies in English. Studies of visual inspection were included that 1) assessed accuracy of the method in detecting caries lesions; 2) were performed on occlusal, proximal, or free smooth surfaces in primary or permanent teeth; 3) had a reference standard; and 4) reported sufficient data about sample size and accuracy of methods. The data were used to calculate the pooled sensitivity, specificity, diagnostic odds ratio, and summary receiver operating characteristics curve. Heterogeneity of the studies was also assessed. A total of 102 manuscripts (from 5,808 articles initially identified) and 1 abstract (from 168) met the inclusion criteria. In general, the analysis demonstrated that the visual method had good accuracy for detecting caries lesions. Although laboratory and clinical studies have presented similar accuracy, clinically obtained specificity was higher. We also observed moderate to high heterogeneity and evidence of publication bias in most papers. Moreover, studies employing widely recognized visual scoring systems presented significantly better accuracy as compared to studies that used their own criteria. In conclusion, visual caries detection method has good overall performance. Furthermore, although the identified studies had high heterogeneity and risk of bias, the use of detailed and validated indices seems to improve the accuracy of the method.

Influence of examiner experience on clinical performance of visual inspection in detecting and assessing the activity status of caries lesions.

Our hypothesis was that a method of caries activity evaluation based on the clinical features of the lesions would be less time consuming but more influenced by the examiner's experience than the scoring system used in association with the International Caries Detection and Assessment System (ICDAS). Thus, the aim of this study was to evaluate the performance of three groups of examiners with different levels of experience using two different methods to assess the activity status of caries lesions by visual inspection. A cross-sectional study in a dental office setting was performed selecting 18 children, aged three to eight years, who had sought dental treatment at a dental school. Examinations to detect caries lesions were performed using visual inspection by six examiners with different levels of experience: two undergraduate dental students, two specialists in pediatric dentistry, and two graduate students. The examiners used ICDAS and two different methods to assess caries activity: using an additional score system or considering the examination of clinical features. Two benchmark examiners examined the children in a joint session, and their consensus was considered to be the reference standard. The sensitivity, specificity, and reproducibility were calculated for different thresholds: all, cavitated, and active caries lesions. Multilevel analyses were performed to compare the different methods and examiners. No differences were observed among the examiners, either in detecting all lesions and cavitated lesions or regarding the activity assessment. The methods of assessing activity status performed similarly, but the time spent on examinations was shorter for the method evaluating clinical features. In conclusion, the experience of examiners does not significantly influence the performance of visual inspection, and both methods of assessing activity status result in similar diagnostic accuracy.

Radiographic and laser fluorescence methods have no benefits for detecting caries in primary teeth.

Clinical guidelines advise that dentists take radiographs in children to detect caries lesions missed by visual inspection; however, due to the current low caries prevalence in most countries, we hypothesized that the adjunct methods of caries detection would not significantly improve the detection of primary molar lesions in comparison to visual inspection alone. We evaluated the performance of visual inspection, alone or in combination with radiographic and laser fluorescence pen (LFpen) methods, in detecting occlusal and approximal caries lesions in primary molars. Two examiners evaluated children who had sought dental treatment with these diagnostic strategies. The reference standard involved the temporary separation of approximal and operative interventions for occlusal surfaces. The sensitivity, specificity, accuracy and utility of diagnostic strategies were calculated. Simultaneous combined strategies increased sensitivities but decreased specificities. Furthermore, no differences were observed in accuracy and utility, parameters more influenced by caries prevalence. In conclusion, adjunct radiographic and laser fluorescence methods offer no benefits to the detection of caries in primary teeth in comparison to visual inspection alone; hence, present clinical guidelines should be re-evaluated.

C957T polymorphism of the dopamine D2 receptor gene is associated with motor learning and heart rate.

Genetic variants that are related to the dopaminergic system have been frequently found to be associated with various neurological and mental disorders. Here, we studied the relationships between some of these genetic variants and some cognitive and psychophysiological processes that are implicated in such disorders. Two single nucleotide polymorphisms were chosen: one in the dopamine D2 receptor gene (rs6277-C957T) and one in the catechol-O-methyltransferase gene (rs4680-Val158Met), which is involved in the metabolic degradation of dopamine. The performance of participants on two long-term memory tasks was assessed: free recall (declarative memory) and mirror drawing (procedural motor learning). Heart rate (HR) was also monitored during the initial trials of the mirror-drawing task, which is considered to be a laboratory middle-stress generator (moderate stress), and during a rest period (low stress). Data were collected from 213 healthy Caucasian university students. The C957T C homozygous participants showed more rapid learning than the T allele carriers in the procedural motor learning task and smaller differences in HR between the moderate- and the low-stress conditions. These results provide useful information regarding phenotypic variance in both healthy individuals and patients.

A retrospective study about the influence of early nutritional support on mortality and nosocomial infection in the critical care setting.

BACKGROUND & AIMS: To determine whether early nutritional support reduces mortality and the incidence of nosocomial infection, in critically ill patients in the current practice. METHODS: A retrospective observational study was conducted in all critically ill patients who had been prescribed nutritional support, throughout one year, in an Intensive Care Unit. The time to start and the route of delivery of nutritional support were determined by the attending clinician's assessment of gastrointestinal function and hemodynamic stability. Age, gender, severity of illness, start time and route of nutritional support, prescribed and delivered daily caloric intake for the first 7 days, whether they were a medical or surgical patient, length of stay in ICU, incidence rate of nosocomial infections and ICU mortality were recorded. Patients were classified according to whether or not they received nutritional support within 48 h of their admission to ICU and Binary Logistic Regression was performed to assess the effect of early nutritional support on ICU mortality and ICU nosocomial infections after controlling for confounders. RESULTS: Ninety-two consecutive patients were included in the study. Start time of nutritional support showed a mean of 3.1 ± 1.9 days. Patients in the early nutritional support group had a lower ICU mortality in an unadjusted analysis (20% vs. 40.4%, p = 0.033). Early nutritional support was found to be an independent predictor of mortality in the regression analysis model (OR 0,28; 95% confidence interval, 0.09 to 0,84; p = 0.023). Our study did not demonstrate any association between early nutritional support and the incidence of nosocomial infection (OR 0.77; 95%. confidence interval, 0.26 to 2,24; p = 0.63), which was related to the route of nutritional support and the caloric intake. The delayed nutritional support group showed a longer length of stay and nosocomial infections than the early group, although these differences were not statistically significant. CONCLUSIONS: Our study shows that early nutrition support reduces ICU mortality in critically ill patients, although it does not demonstrate any influence over nosocomial infection in the current practice in intensive care.

¿Podemos influir de forma efectiva sobre la conducta de clínicos y directivos? / No disponible

El liderazgo, entendido como la capacidad de un profesional y/o un servicio para influir sobre otros profesionales y/o servicios para que trabajen y se involucren en el logro de objetivos comunes, es una función clave de los servicios de medicina preventiva y unidades de calidad asistencial para promover e implementar iniciativas e incentivar y motivar a grupos y equipos en relación con la calidad asistencial y la seguridad del paciente. Aspectos clave a considerar para lograr cambios en individuos y organizaciones son: evidencia de las intervenciones, conocimiento de las actitudes de los profesionales, perseverancia, participación y existencia de un plan de implementación. Existen distintos planteamientos para abordar cambios de conductas entre los profesionales sin evidencia suficiente para recomendar uno u otro. A pesar de sus limitaciones, todos tienen elementos positivos para ser utilizados con mesura, en función de cada realidad asistencial (AU)

Leadership, understood as the power of a professional and/or service to influence other professionals and/or services to work and engage in achieving common goals is a key function of Preventive and Quality of Care Departments to promote and implement initiatives and encourage and motivate teams and groups in relation to the quality of care and patient safety. Key issues to consider for change in individuals and organizations are: evidence of the interventions, knowledge of professional attitudes, perseverance, participation and carry out an implementation plan. There are different approaches to achieve behavior changes among professionals without sufficient evidence to recommend one or the other. Despite their limitations, they all have positive elements to be used sparingly, depending on each health care locations (AU)

Diarrheic syndrome as a clinical sign of intestinal infiltration in progressive B-cell chronic lymphocytic leukemia.

Gastrointestinal involvement is a rare event in patients with B-cell chronic lymphocytic leukemia (B-CLL) and is usually associated to lymphomatous transformation. However, in autopsy studies the reported incidence of microscopic infiltration can reach up to 50% of cases. Seven B-CLL patients in advanced stage/progressive disease were evaluated by colonoscopy because of continuous diarrhea. Five out of seven patients (71%) presented histological evidence of colonic infiltration. Persistent diarrhea in patients with progressive/advanced B-CLL can be a clinical sign of intestinal infiltration and justifies endoscopic examinations.

Fluorometría; un método rápido y sencillo para evaluar la Actividad Antipalúdica / Fluorometers; a rapid and simple method for evaluating the Antimalarial Activity

La Malaria es una enfermedad que oscila entre 250 y 300 millones de casos y aproximadamente dos millones de muertes anualmente1. Esta enfermedades causada por cuatro especies de Plasmodium (P.falciparum, P. vivax, P.ovale y P. malariae) que son transmitidas a los humanos por picadura de las hembras del mosquito Anopheles. El aumento de la resistencia del parásito al tratamiento con agentes antimaláricos conocidos como la cloroquina se convierte en uno de los aspectos responsables del crecimiento de esta enfermedad. Además de este problema también se cuenta con la resistencia delvector a los insecticidas y la limitación de una potencial vacuna antimalárica, todo esto contribuye a la necesidad urgente de encontrar nuevos agentes para el tratamiento de la malaria, en particular agentes efectivos contra P. falciparum, que es la responsable de la forma más severa de malaria.

Establecimiento de células en suspensión de Stevia rebaudiana Bertoni / Establishhment of cells in suspension of stevia rebaudiana Bertoni

Stevia rebaudiana B., es un arbusto de origen paraguayo que posee en sus hojas, glucósidos diterpenos conocidos comúnmente como steviosidos totales (Molinas, S. 1989).. Es empleada comoedulcorante natural de alta potencia, (± 300 veces más dulce que el azúcar), termoestable, hipoglisemiante, no produce caries, es hipotensiva, no calórica, inocua para la salud y con actividad antimicrobiana contraalgunos microorganismos.

Establecimiento de las condiciones para la producción de Biogas a partir de ácidos grasos volátiles obtenidos de la Hidrólisis anaeróbica de la papa (Solanum tuberosum) a nivel de laboratorio / Establishment of the conditions for the production of biogas based on obtained volatile fatty acids of the anaerobic Hydrolysis of the potato (Solanum tuberosum) at the level of laboratory

En este trabajo se ha estudiado las condicionesnecesarias para la producción de Biogas utilizando como fuente de carbono los Ácidos Grasos Volátiles, los cuales son obtenidos de la hidrólisis anaeróbica de la papa. Se han establecido Cultivos Batch metanogénicos y se ha determinado la influencia de los AGVs en la cinética de producción de Metano. De esta manera se observ que el Cultivo que tenía 11,68mg/ml de AGVs Totales tuvo una producción de 6,9% de Metano y 3,6% de Dióxido de Carbono, a los 45 días de haberse establecido el cultivo.Posteriormente, se estableci el cultivo continuo, en el cual la producción de biogás empez a los 11 días deestablecerse el cultivo, se obtuvo 1200 ml de Gas donde el 6,9% era Metano y 3,7% era Dióxido de carbono. La composición de gases fue medida con el detector portátil G3.16k – LT 1522 LMSx.

Estudio biodirigidos de Solanum argentinum sobre plasmodium falciparum / I study biodirigidos of Solanum argentinum it has more than enough plasmodium falciparum

El presente trabajo es parte del proyecto "Flora Regional como fuente de fármacos antiparasitarios, antifúngicos y anticancerígenos" financiado por la Organización de Estados Americanos (OEA) que se ejecuta en el Instituto de Investigaciones Farmaco Bioquímicas, desde el año 2001. Los principios activos de las partes aéreas de la planta Solanum argentinum, fueron extraídos medianate maceración alchohólica (70 por ciento) y parcialmente purificados por Cromatografia líquida al vació, obteniéndose 9 fracciones con valores de IC50 (concentración inhibitoria del 50 por ciento aceptables (11<10 ug/ml), en la inhibición sobre la maduración de los esquizontes (prueba in vitro). Los valores de IC50 en el Test de Inhibición de la Biomineralización de la Ferriprotoporfirina IX (FBIT), como indicadores de su posible mecanismo de acción también fueron hallados con resultados aceptables (<10mg/ml). Las fracciones activas contra esquizontes se subfraccionaron por cromatografía en columna donde se obtubieron 5 subfracciones activas F3-7, F4-10, F4-12, F5-17 y F5-18.

Actividad Leishmanicida y tripanocida de algunas plantas reportadas como medicinales en Colombia / Activity Leishmanicida and tripanocida of some plants reported as medicinal in Colombia

Ocho extractos crudos y dos fracciones de alcaloides obtenidos de siete especies vegetales provenientes de la flora colombiana, (abuta grandifolia, Piper holtonii, Acnistus arborescens, Croton leptostachys, Piper cumanense, Acacia farnesiana y Xilopia aromática) fueron evaluadas in vitro frente a tres especies de Leishmania danovanni y Leismania braziliensis y epimastigotes de Trypanosoma cruzi (tulahuen); dos de estas epecies (Acnistus arborescens y Piper cumanense) mostraron alta actividad en los ensayos realizados con valores de concentración inhibitoria 50 (CL50) menores de 12,5 ug/mL; cercanos a los obtenidos con el fármaco de referencia pentamidina 10 ug/mL.