Pratylenchus Araucensis (Rhabditida: Pratylenchidae) a Widely Distributed Nematode in Musa Spp. from Colombia.

Pratylenchus is one of the most limiting nematodes of Musaceae production in the world. Knowledge of the nematode species is one of the requirements for its management in the field. This study aimed to identify up to the species level Pratylenchus populations associated with plantain and banana crops in the states of Caldas, Quindío, and Valle del Cauca in Colombia. In these regions, Pratylenchus has been reported to affect these crops in the past, but with records of the nematode only up to the genus level. For this purpose, five populations of Pratylenchus extracted from samples composed of roots and rhizospheric soil, four from plantain and one from banana, were identified through morphological, morphometric, and molecular analysis (sequencing of the D2-D3 of rRNA and cytochrome oxidase subunit I of mtDNA). All populations were identified as P. araucensis, a species reported previously in eastern Colombia, and one that the present study found in the center and southwest of the country, indicating that this species of nematode is widely distributed in the Musaceae-producing areas of Colombia. The present study reports the first COI mtDNA sequences for this species of nematode.

Seropositivity for Bovine Viral Diarrhea and Enzootic Bovine Leukemia viruses in Blanco Orejinegro cattle in Colombia and infection associated-factors / Soropositividade para o vírus da diarréia viral bovina e leucemia bovina enzoótica em bovinos Blanco Orejinegro na Colômbia e fatores associados à infecção

ABSTRACT Serological controls for diseases of viral origin in animal production systems and the identification of factors associated with infections are decisive elements to establish prevention and control measures. The aim of this study was to establish the serological status for Bovine Viral Diarrhea (BVD) and Enzootic Bovine Leukemia (EBL) viruses in Blanco Orejinegro (BON) cattle from Colombia, and to identify the factors associated with seropositivity. A cross-sectional study was conducted with a total of 498 animals of all age groups and physiological states of the BON breed were selected, belonging to 14 herds located in 6 states of Colombia, in which a survey with 27 questions was conducted. By means of the chi-square test, possible factors associated with seropositivity against the 2 viruses were identified. A sample of 4 ml of blood was taken from each animal to extract plasma and make indirect Elisa tests to detect antibodies against both pathogens. General seropositivity of 27,1% was obtained for EBL, finding as factors associated with seropositivity the inadequate disposition of placental tissues after delivery of the cows and the non-performance of serological tests on new animals entering the herd. For BVD, seropositivity obtained was 50,6%, and the factors associated with seropositivity identified were having had a history of the disease in the herd, and using semen from bulls that are not known to be free for the infection. We suggest establishing control measures considering the factors associated with each viral infection to limit their expansion in the BON cattle production systems of Colombia.

RESUMO Os controles sorológicos para doenças de origem viral nos sistemas de produção animal e a identificação de fatores associados à infecção são elementos decisivos para estabelecer medidas de prevenção e controle. O objetivo deste estudo foi estabelecer o status sorológico dos vírus da Diarréia Viral Bovina (BVD) e da Leucemia Bovina Enzoótica (EBL) em bovinos Blanco Orejinegro (BON) da Colômbia e identificar os fatores associados à soropositividade. Foram selecionados 498 animais de todas as faixas etárias e estados fisiológicos da raça BON, de 14 rebanhos localizados em seis regiões da Colômbia, nos quais foi realizada uma pesquisa para identificar possíveis fatores associados à soropositividade contra os dois vírus. Foi retirada uma amostra de 4 ml de sangue de cada animal para extrair plasma e fazer testes ELISA indiretos para detectar anticorpos contra os dois patógenos. Obteve-se soropositividade geral de 27,1% para EBL, encontrando como fatores associados à soropositividade a disposição inadequada dos tecidos placentários após o parto das vacas e a não realização de testes sorológicos em novos animais que entraram no rebanho. Para a BVD, a soropositividade obtida foi de 50,6%, e os fatores associados à soropositividade identificados foram: histórico de doença no rebanho e uso de sêmen de touros que não são reconhecidos como livres da infecção. Sugerimos o estabelecimento de medidas de controle considerando os fatores associados a cada infecção viral para limitar sua expansão nos sistemas de produção de gado BON da Colômbia.

ZnO-based nanofungicides: Synthesis, characterization and their effect on the coffee fungi Mycena citricolor and Colletotrichum sp.

In this work we compare the antifungal capacity of zinc oxide nanoparticles (ZnO-NPs) synthesized by a chemical route and a ZnO-based nanobiohybrid obtained by green synthesis in an extract of garlic (Allium sativum). To find out the characteristics of the materials synthesized, X-ray diffraction (XRD), IR spectroscopy and absorption in UV-Vis were used, as well as both scanning (SEM) and transmission (TEM) electron microscopy. The results showed that the samples obtained were of nanometric size (<100 nm), with a predominance of the wurtzite crystal phase of ZnO and little crystallization of the nanobiohybrids. Their antifungal capacity on two pathogenic fungi of coffee, Mycena citricolor (Berk and Curt) and Colletotrichum sp. was also evaluated. Both nanomaterials showed an efficient antifungal capacity, particularly the nanobiohybrids, with ~97% inhibition in growth of M. citricolor, and ~93% for Colletotrichum sp. The microstructural study with high resolution optical (HROM) and ultra-structural microscopy (using TEM) carried out on the fungi treated with the synthesized nanomaterials showed a strong nanofungicidal effect on the vegetative and reproductive structures and fungal cell wall, respectively. The inhibition of the growth of the fungi and micro and ultra-structural affectations were explained considering that the size of the nanomaterials allows them to pass easily through the cell membranes. This indicates that they can be absorbed easily by the fungi tested here, causing cellular dysfunction. Nanofungicide effects are also attributable to the unique properties of nanomaterials, such as the high surface-to-bulk ratio of atoms and their surface physicochemical characteristics that could directly or indirectly produce reactive oxygen species (ROS), which affect the proteins of the cell wall.

Antimicrobial activity of a new synthetic peptide loaded in polylactic acid or poly(lactic-co-glycolic) acid nanoparticles against Pseudomonas aeruginosa, Escherichia coli O157:H7 and methicillin resistant Staphylococcus aureus (MRSA).

Nanocarrier systems are currently being developed for peptide, protein and gene delivery to protect them in the blood circulation and in the gastrointestinal tract. Polylactic acid (PLA) and poly(lactic-co-glycolic) acid (PLGA) nanoparticles loaded with a new antimicrobial GIBIM-P5S9K peptide were obtained by the double emulsion solvent extraction/evaporation method. PLA- and PLGA-NPs were spherical with sizes between 300 and 400 nm for PLA and 200 and 300 nm for PLGA and <0.3 polydispersity index as determined by dynamic light scattering and scanning electron microscopy), having the zeta potential of >20 mV. The peptide-loading efficiency of PLA-NP and PLGA-NPs was 75% and 55%, respectively. PLA- and PLGA-NPs released around 50% of this peptide over 8 h. In 10% human sera the size of peptide loaded PLA- and PLGA-NPs increased between 25.2% and 39.3%, the PDI changed from 3.2 to 5.1 and the surface charge from -7.15 to 14.6 mV. Both peptide loaded PLA- and PLGA-NPs at 0.5 µM peptide concentration inhibited the growth of Escherichia coli O157:H7 (E. coli O157:H7), methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas. aeruginosa (P. aeruginosa). In contrast, free peptide inhibited at 10 µM but did not inhibit at 0.5 and 1 µM. These PLA- and PLGA-NPs presented <10% hemolysis indicating that they are hemocompatible and promising for delivery and protection system of GIBIM-P5S9K peptide.

Genetic variation in blue whales in the eastern pacific: implication for taxonomy and use of common wintering grounds.

Many aspects of blue whale biology are poorly understood. Some of the gaps in our knowledge, such as those regarding their basic taxonomy and seasonal movements, directly affect our ability to monitor and manage blue whale populations. As a step towards filling in some of these gaps, microsatellite and mtDNA sequence analyses were conducted on blue whale samples from the Southern Hemisphere, the eastern tropical Pacific (ETP) and the northeast Pacific. The results indicate that the ETP is differentially used by blue whales from the northern and southern eastern Pacific, with the former showing stronger affinity to the region off Central America known as the Costa Rican Dome, and the latter favouring the waters of Peru and Ecuador. Although the pattern of genetic variation throughout the Southern Hemisphere is compatible with the recently proposed subspecies status of Chilean blue whales, some discrepancies remain between catch lengths and lengths from aerial photography, and not all blue whales in Chilean waters can be assumed to be of this type. Also, the range of the proposed Chilean subspecies, which extends to the Galapagos region of the ETP, at least seasonally, perhaps should include the Costa Rican Dome and the eastern North Pacific as well.

Survival of acral lentiginous melanoma in the National Cancer Institute of Colombia.

OBJECTIVE: To determine survival of a cohort of patients with acral lentiginous melanoma (ALM), treated at the National Cancer Institute of Colombia, the largest referral hospital of the country. METHODS: All patients diagnosed with an invasive ALM between 2003 and 2009 at the Colombian National Cancer Institute were included for analyses and followed for vital status and date of death. Using Kaplan-Meier methods, overall survival at 1, 3 and 5 years post diagnosis was determined, and Cox proportional hazards models were constructed for the variables showing a significant effect on survival in univariate analyses. RESULTS: Overall survival of this cohort of 90 patients was 77% at 1 year, 59% at 3 years and 54% at 5 years after diagnosis. Females had a better prognosis in univariate analyses but this advantage disappeared in multivariate models. Clinical stage was a strong predictor of survival, in univariate and multivariate models, particularly among elderly patients. CONCLUSIONS: Prognosis of ALM in Colombia is relatively poor, particularly for patients with higher clinical stage. The large proportions of ALM diagnosed in stage III and IV explain the relatively poor survival, and illustrate the importance of improving prognosis by lowering stage at diagnosis through better education and early detection programmes.

Geometrically frustrated Fe2P-like systems: beyond the Fe-trimer approximation.

Fe(2)P-like structures can be strongly frustrated magnets due to their Kagome/triangular intercalated-layer structure. A complete magnetic solution of the complex spin architecture, and hence the full potential of the magnetic phenomena in Fe(2)P-like material prototypes, is yet to be found. A previous magnetic model for a representative FeCrAs-like system used a mean-field effective-spin to describe the 3g-Wyckoff located Fe-triangles. Such an approach demonstrated the outstanding magnetocaloric properties of the material but left the question of whether the intra-trimer interaction could lead to new physical phenomena and therefore more potentially useful properties. In this work Monte Carlo simulations are employed in order to understand both the influence of the additional degrees of freedom introduced by the Fe-trimers and the changes caused by all the possible exchange couplings between them. Complex scenarios arise, in which FM coupling in the trimers gives rise to both in-plane and out-of-plane inter-layer AFM states; whereas AFM exchange in the trimers gives rise to three distinct states, i.e. AFM-canted layers, a non-collinear superposition of ferromagnetic Kagome/triangular orderings, and tilted inter-planar AFM order. These last three configurations generate a double bifurcated magnetic phase diagram while the first one mimics the behavior seen in a model that treats the trimer as an effective-spin under an applied magnetic field.

Blue whale population structure along the eastern South Pacific Ocean: evidence of more than one population.

Blue whales (Balaenoptera musculus) were among the most intensively exploited species of whales in the world. As a consequence of this intense exploitation, blue whale sightings off the coast of Chile were uncommon by the end of the 20th century. In 2004, a feeding and nursing ground was reported in southern Chile (SCh). With the aim to investigate the genetic identity and relationship of these Chilean blue whales to those in other Southern Hemisphere areas, 60 biopsy samples were collected from blue whales in SCh between 2003 and 2009. These samples were genotyped at seven microsatellite loci and the mitochondrial control region was sequenced, allowing us to identify 52 individuals. To investigate the genetic identity of this suspected remnant population, we compared these 52 individuals to blue whales from Antarctica (ANT, n = 96), Northern Chile (NCh, n = 19) and the eastern tropical Pacific (ETP, n = 31). No significant differentiation in haplotype frequencies (mtDNA) or among genotypes (nDNA) was found between SCh, NCh and ETP, while significant differences were found between those three areas and Antarctica for both the mitochondrial and microsatellite analyses. Our results suggest at least two breeding population units or subspecies exist, which is also supported by other lines of evidence such as morphometrics and acoustics. The lack of differences detected between SCh/NCh/ETP areas supports the hypothesis that eastern South Pacific blue whales are using the ETP area as a possible breeding area. Considering the small population sizes previously reported for the SCh area, additional conservation measures and monitoring of this population should be developed and prioritized.

Clinical description and evolution of renal transplant pediatric patients treated with alemtuzumab.

BACKGROUND: Renal transplantation is the most effective treatment for children with end-stage renal disease. Recent work suggests that induction with alemtuzumab in the pediatric population permits the use of lower doses of maintenance immunosuppressive therapy. In addition, it has a low cost compared with other induction therapies. OBJECTIVE: To conduct a clinical description of pediatric renal transplant patients comparing induction protocols to evaluate graft and patient survival, infections complications, and lymphoproliferative diseases. MATERIALS AND METHODS: This descriptive and retrospective study, of evaluated pediatric renal transplant patients between 2006 and 2010. RESULTS: The agents for induction therapy were: alemtuzumab (61.5%), daclizumab (19.25%), and thymoglobulin (19.25%). Graft survival was better among the alemtuzumab group (87.5%) compared with the other two induction therapies (80%). The frequency of acute rejection episodes during the first year posttransplantation as well as chronic rejection was lower among the alemtuzumab group. Cytomegalovirus infection was noted in 30% of patients with greater frequency among those induced with alemtuzumab. CONCLUSION: Induction therapy with alemtuzumab was safe in a pediatric population not predisposing to a greater risk of acute or chronic rejection. Except for a greater incidence of Cytomegalovirus, there was no difference in other complications.

Quantum tunneling in nanomagnetic systems with different uniaxial anisotropy order.

A study of macroscopic quantum tunneling (MQT) of the magnetic moment in systems with quadratic and higher order uniaxial anisotropy and Zeeman interaction is presented. By using the instanton technique, under the giant spin approximation, the escape rate or probability per unit of time Gamma that the system undergoes a transition between coherent or metastable states is calculated. Using an effective particle potential we also determine the escape temperature T(e)(T), which marks the transition from quantum tunneling to thermal activation. A discussion is presented about the different models and the behavior of the magnetic system under the tunneling regime.

Strong association of socioeconomic status with genetic ancestry in Latinos: implications for admixture studies of type 2 diabetes.

AIMS/HYPOTHESIS: Type 2 diabetes is more prevalent in US American minority populations of African or Native American descent than it is in European Americans. However, the proportion of this epidemiological difference that can be ascribed to genetic or environmental factors is unknown. To determine whether genetic ancestry is correlated with diabetes risk in Latinos, we estimated the proportion of European ancestry in case-control samples from Mexico and Colombia in whom socioeconomic status had been carefully ascertained. METHODS: We genotyped 67 ancestry-informative markers in 499 participants with type 2 diabetes and 197 controls from Medellín (Colombia), as well as in 163 participants with type 2 diabetes and 72 controls from central Mexico. Each participant was assigned a socioeconomic status scale via various measures. RESULTS: Although European ancestry was associated with lower diabetes risk in Mexicans (OR [95% CI] 0.06 [0.02-0.21], p = 2.0 x 10(-5)) and Colombians (OR 0.26 [0.08-0.78], p = 0.02), adjustment for socioeconomic status eliminated the association in the Colombian sample (OR 0.64 [0.19-2.12], p = 0.46) and significantly attenuated it in the Mexican sample (OR 0.17 [0.04-0.71], p = 0.02). Adjustment for BMI did not change the results. CONCLUSIONS/INTERPRETATION: The proportion of non-European ancestry is associated with both type 2 diabetes and lower socioeconomic status in admixed Latino populations from North and South America. We conclude that ancestry-directed search for genetic markers associated with type 2 diabetes in Latinos may benefit from information involving social factors, as these factors have a quantitatively important effect on type 2 diabetes risk relative to ancestry effects.