Identificación molecular y diversidad genética de las especies de nematodos Globodera rostochiensis y G. pallida en regiones productoras de papa de Guatemala / Molecular identification and genetic diversity of the species of nematodesGlobodera rostochiensisandG. pallidain potato growing regions of Guatemala

En Guatemala, la producción del cultivo de papa se ve afectada por los nematodos Globodera rostochiensis y Globo-dera pallida. La capacidad de ambas especies para formar quistes complica su control y provoca el aumento de sus poblaciones. En Guatemala se reporta la presencia de ambas especies de nematodos por identificación morfológica, sin embargo, no se ha realizado una confirmación molecular. Este es el primer estudio para validar la presencia de ambas especies de nematodos por PCR múltiple y la determinación de la diversidad y estructura genética de las poblaciones utilizando marcadores moleculares. Se realizaron muestreos en cuatro departamentos productores de papa del país. La identificación por PCR se realizó con el cebador común ITS5 y los cebadores PITSr3 específico para G. rostochiensisy PITSp4 para G. pallida. La caracterización molecular se realizó con el marcador AFLP. Se confirmó la presencia de las dos especies de nematodos en los cuatro departamentos. Los índices de diversidad Shannon y heterocigosidad esperada revelaron mayor diversidad genética en G. rostochiensis (H = 0.311, He = 0.301) que en G. pallida (H = 0.035, He = 0.223). Los métodos NJ, DAPC y PCA exhibieron una débil estructura entre las poblaciones de ambas especies de nematodos. Los resultados sugieren un patrón de dispersión desde Quetzaltenango hacia el resto del país, atribuido a la comercialización de semilla contaminada con nematodos. Se sugiere promover programas de socialización sobre los beneficios del uso de semilla certificada, además de constantes monitoreos moleculares para un diagnóstico certero de ambas especies de nematodos.

In Guatemala, potato crop production is affected by the nematodes Globodera rostochiensis and Globodera pallida. The ability of both species to form cysts complicates their control and causes an increase in their populations. In Guatemala, both species of nematodes have been reported by morphological identification; however, molecular confirmation has not been carried out. It is the first study to validate the presence of both nematode species by multiplex PCR and determine the diversity and genetic structure of the populations using molecular markers. Sampling was carried out in four pota-to-producing departments of the country. PCR identification was performed with the common primer ITS5 and the primers PITSr3 specific for G. rostochiensis and PITSp4 for G. pallida. We performed molecular characterization with the AFLP marker. We confirmed the presence of the two nematode species in the four departments. Shannon diversity and expected heterozygosity indices revealed higher genetic diversity in G. rostochiensis (H = 0.311, He = 0.301) than in G. pallida (H = 0.035, He = 0.223). The NJ, DAPC, and PCA methods exhibited weak structure among populations of both nematode species. The results suggest a dispersal pattern from Quetzaltenango to the rest of the country, attributed to the commer-cialization of seed contaminated with nematodes. We suggest promoting socialization programs on the benefits of using certified seeds and constant molecular monitoring for an accurate diagnosis of both species of nematodes.

Diseño, estandarización e implementación de una nueva técnica en Guatemala, para el diagnóstico rápido de hemocultivos positivos, utilizando la tecnología Maldi-tof / Design, standardization and implementation of a new technique in Guatemala, for the rapid diagnosis of positive blood cultures, using Maldi-tof technology

Las enfermedades infecciosas son un problema de salud que a pesar de los avances médicos siguen cobrando vi-das en todo el mundo; como las septicemias. La presente investigación tuvo por objetivo diseñar, estandarizar e implementar un protocolo inexistente en Guatemala, para el diagnóstico rutinario de hemocultivos positivos dentro de las instalaciones del Laboratorio Clínico del Hospital General San Juan de Dios, lugar en donde se encuentra el único espectrómetro de masas de tipo Maldi-tof (Matrix Assisted Laser Desorption Ionization-Time of flight-mass spectrometry).Se utilizaron 240 muestras de pacientes de los diferentes servicios. El diagnóstico se realizó compa-rando las identificaciones obtenidas a partir de cultivos microbiológicos puros con muestras directas de botellas con caldo BHI(Brain Heart Infusion).Los resultados de las dos metodologías fueron evaluados con el diseño estadístico "apareado o emparejado en grupo". La comparación no evidenció discordancia en las identificaciones; pero sí en los tiempos de respuesta. La reducción de tiempo fue de 42.9 h para bacterias Gram positivo, 45.0 h para bacterias Gram negativo y 126.2 h para levaduras, todos a favor de identificaciones a partir de muestras directas. Con esta investigación se pretende ofrecer una nueva alternativa que permitirá brindar un diagnóstico rápido, confiable y certero a la población guatemalteca. También permitirá reducir la morbimortalidad de los pacientes con septicemias, promover el ahorro de insumos hospitalarios, disminuir el tiempo de estancia hospitalaria, ahorrar el consumo de antibióticos innecesarios y contribuir indirectamente a combatir la resistencia antimicrobiana; un problema actual de gran importancia a nivel mundial.

Infectious diseases are a health problem that despite medical advances in terms of diagnosis continue to take lives worldwide, such is the case of sepsis. The purpose of this research was to design, standardize and implement a non-existent protocol in Guatemala, for the routine diagnosis of positive blood cultures, within the facilities of the clinical laboratory of the San Juan de Dios General Hospital; where the only Maldi-tof (Matrix Assisted Laser Desorp-tion Ionization-Time of flight-mass spectrometry) type mass spectrometer is located. For this, 240 samples of positive blood cultures were used, coming from patients of the different services. The microbiological diagnosis was made by comparing the identification data obtained from pure microbiological cultures and direct samples of BHI broth (Brain Heart Infusion) bottles. The results of the two methodologies were evaluated based on "paired or matched in groups" statistical design. The Maldi-tof technique did not show disagreement regarding identification between the two types of samples; but it did in the response time. The time reduction was 42.9 h for Gram positive bacteria, 45.0 h for Gram negative and 126.2 h for yeasts, supporting identification from direct samples. This research aims to provide a new diagnostic alternative that will allow access to fast, reliable, and accurate results for the Guatemalan population. It will also help to reduce e morbidity and mortality rates of patients with sepsis, to promote hospital supplies savings, decrease the patient length of stay, save unnecessary antibiotics and indirectly contribute to combating antimicrobial resistance; a critical problem faced by the world today.

Common pattern of distribution for Mesoamerican Triatoma dimidiata suggest geological and ecological association.

The phylogeny of the Triatoma dimidiata complex has been widely assessed with different genetic and morphological data, which has allowed to reach the consensus that the complex consists of at least three taxonomic units. However, these taxonomic units seem to have a distribution related to geography throughout Mesoamerica, with different groupings depending on the source of information used. In the present study, we aimed to determine if there is a common biogeographical, genetic and phenetic distribution pattern among the T. dimidiata species in Mesoamerica and if this pattern is related to ecological and geological variability of the region. We found that panbiogeographical analysis showed three generalized tracks that coincide with genetic/phenetic data which showed a general pattern of distribution in two big clusters to the north and south of Mesoamerica. We also found that these clusters were significantly related to geological tectonic plates and ecotypes. We conclude that the geological history may be a plausible explanation for the greater differentiation observed in the T. dimidiata complex, but that the current ecological characteristics of the morphotectonic units or ecotypes may be responsible for the additional variation observed and therefore differential control strategies for each cluster considering geological history and ecotype should be used. Further, more detailed biogeographical and landscape genetic analyses are necessary with the goal to elucidate T. dimidiata differentiation related with ecological and geological variables in the region and the possible epidemiological and evolutionary consequences.

A New Metre for Cheap, Quick, Reliable and Simple Thermal Transmittance (U-Value) Measurements in Buildings.

This paper deals with the thermal transmittance measurement focused on buildings and specifically in building energy retrofitting. Today, if many thermal transmittance measurements in a short time are needed, the current devices, based on the measurement of the heat flow through the wall, cannot carry out them, except if a great amount of devices are used at once along with intensive and tedious post-processing and analysis work. In this paper, from well-known physical laws, authors develop a methodology based on three temperatures measurements, which is implemented by a novel thermal transmittance metre. The paper shows its development step by step. As a result the developed device is modular, scalable, and fully wireless; it is capable of taking as many measurements at once as user needs. The developed system is compared working together on a same test to the currently used one based on heat flow. The results show that the developed metre allows carrying out thermal transmittance measurements in buildings in a cheap, quick, reliable and simple way.

Ground Thermal Diffusivity Calculation by Direct Soil Temperature Measurement. Application to very Low Enthalpy Geothermal Energy Systems.

This paper presents a methodology and instrumentation system for the indirect measurement of the thermal diffusivity of a soil at a given depth from measuring its temperature at that depth. The development has been carried out considering its application to the design and sizing of very low enthalpy geothermal energy (VLEGE) systems, but it can has many other applications, for example in construction, agriculture or biology. The methodology is simple and inexpensive because it can take advantage of the prescriptive geotechnical drilling prior to the construction of a house or building, to take at the same time temperature measurements that will allow get the actual temperature and ground thermal diffusivity to the depth of interest. The methodology and developed system have been tested and used in the design of a VLEGE facility for a chalet with basement at the outskirts of Huelva (a city in the southwest of Spain). Experimental results validate the proposed approach.

Two distinct Triatoma dimidiata (Latreille, 1811) taxa are found in sympatry in Guatemala and Mexico.

Approximately 10 million people are infected with Trypanosoma cruzi, the causative agent of Chagas disease, which remains the most serious parasitic disease in the Americas. Most people are infected via triatomine vectors. Transmission has been largely halted in South America in areas with predominantly domestic vectors. However, one of the main Chagas vectors in Mesoamerica, Triatoma dimidiata, poses special challenges to control due to its diversity across its large geographic range (from Mexico into northern South America), and peridomestic and sylvatic populations that repopulate houses following pesticide treatment. Recent evidence suggests T. dimidiata may be a complex of species, perhaps including cryptic species; taxonomic ambiguity which confounds control. The nuclear sequence of the internal transcribed spacer 2 (ITS2) of the ribosomal DNA and the mitochondrial cytochrome b (mt cyt b) gene were used to analyze the taxonomy of T. dimidiata from southern Mexico throughout Central America. ITS2 sequence divides T. dimidiata into four taxa. The first three are found mostly localized to specific geographic regions with some overlap: (1) southern Mexico and Guatemala (Group 2); (2) Guatemala, Honduras, El Salvador, Nicaragua, and Costa Rica (Group 1A); (3) and Panama (Group 1B). We extend ITS2 Group 1A south into Costa Rica, Group 2 into southern Guatemala and show the first information on isolates in Belize, identifying Groups 2 and 3 in that country. The fourth group (Group 3), a potential cryptic species, is dispersed across parts of Mexico, Guatemala, and Belize. We show it exists in sympatry with other groups in Peten, Guatemala, and Yucatan, Mexico. Mitochondrial cyt b data supports this putative cryptic species in sympatry with others. However, unlike the clear distinction of the remaining groups by ITS2, the remaining groups are not separated by mt cyt b. This work contributes to an understanding of the taxonomy and population subdivision of T. dimidiata, essential for designing effective control strategies.

Salivary protein profiles distinguish triatomine species and populations of Triatoma dimidiata (Hemiptera: Reduviidae).

Seven Triatoma dimidiata (Latreille, 1811) populations from different provinces of Guatemala were compared along with three related triatomine species using the electrophoretic profiles of salivary proteins. The analysis of salivary proteins allowed the separation of two of the species into their respective complexes, phyllosoma (T. pallidipennis) and protracta (T. nitida) (Lent and Wygodzinsky, 1979), whereas T. dimidiata seems slightly separated from either of these. Based on salivary protein profiles, T. dimidiata is most closely related to the cluster including T ryckmani and T. nitida (protracta) and more diverged from T. pallidipennis (phyllosoma). Among Guatemalan T. dimidiata populations, the cave population from Lanquin is separated from the rest of populations analyzed, suggesting that it is in the process of speciation. No difference in protein banding pattern was observed among populations from domestic and peridomestic ecotopes from the same region.

Creating an integrated clinical enterprise at the University of Kentucky: the emergence of UK HealthCare.

If the medical system in the United States is to change, as has been recommended, academic medical centers must, in fact, lead this change process. To prepare for the future, the University of Kentucky decided to move aggressively toward developing an integrated clinical enterprise branded as UK HealthCare, where leadership of the various components of the academic medical center make strategic and financial decisions together to achieve common organizational goals. The authors discuss senior leadership's development of the vision for the enterprise and the governance structure that was established to engage board members and faculty of the institution. They examine the rigorous strategic, facilities, financial, and academic planning that ensued, and the early successes achieved. The authors introduce some of the lessons learned by the organization during the emergence of UK HealthCare and describe the corporate structure and senior management team that was established to support the quick and efficient implementation of the planning strategies. It was this corporate structure and senior management team which has proven to be an effective agent of change and a key to the successful development of a truly integrated clinical enterprise.

The number of families of Triatoma dimidiata in a Guatemalan house.

Triatoma dimidiata is an important vector of Chagas disease in Guatemala. To help understand the biology and population dynamics of the insect, we estimated the number of full sibling families living in one house. Forty one families with an average size of 2.17 individuals were detected using random amplification of polymorphic DNA-polymerase chain reaction genetic markers. This result suggests high levels of migration of the vector, polyandry, and a significant capability for spreading the disease.

The number of families of Triatoma dimidiata in a Guatemalan house

Triatoma dimidiata is an important vector of Chagas disease in Guatemala. To help understand the biology and population dynamics of the insect, we estimated the number of full sibling families living in one house. Forty one families with an average size of 2.17 individuals were detected using random amplification of polymorphic DNA-polymerase chain reaction genetic markers. This result suggests high levels of migration of the vector, polyandry, and a significant capability for spreading the disease.

Comparative sequence and genetic analyses of asparagus BACs reveal no microsynteny with onion or rice.

The Poales (includes the grasses) and Asparagales [includes onion (Allium cepa L.) and asparagus (Asparagus officinalis L.)] are the two most economically important monocot orders. The Poales are a member of the commelinoid monocots, a group of orders sister to the Asparagales. Comparative genomic analyses have revealed a high degree of synteny among the grasses; however, it is not known if this synteny extends to other major monocot groups such as the Asparagales. Although we previously reported no evidence for synteny at the recombinational level between onion and rice, microsynteny may exist across shorter genomic regions in the grasses and Asparagales. We sequenced nine asparagus BACs to reveal physically linked genic-like sequences and determined their most similar positions in the onion and rice genomes. Four of the asparagus BACs were selected using molecular markers tightly linked to the sex-determining M locus on chromosome 5 of asparagus. These BACs possessed only two putative coding regions and had long tracts of degenerated retroviral elements and transposons. Five asparagus BACs were selected after hybridization of three onion cDNAs that mapped to three different onion chromosomes. Genic-like sequences that were physically linked on the cDNA-selected BACs or genetically linked on the M-linked BACs showed significant similarities (e < -20) to expressed sequences on different rice chromosomes, revealing no evidence for microsynteny between asparagus and rice across these regions. Genic-like sequences that were linked in asparagus were used to identify highly similar (e < -20) expressed sequence tags (ESTs) of onion. These onion ESTs mapped to different onion chromosomes and no relationship was observed between physical or genetic linkages in asparagus and genetic linkages in onion. These results further indicate that synteny among grass genomes does not extend to a sister order in the monocots and that asparagus may not be an appropriate smaller genome model for plants in the Asparagales with enormous nuclear genomes.

A preliminary assessment of genetic differentiation of Triatoma dimidiata (Hemiptera: Reduviidae) in Guatemala by random amplification of polymorphic DNA-polymerase chain reaction.

The population genetics of Triatoma dimidiata (Latreille, 1811) from five different provinces in Guatemala, including three sylvan and three domestic populations, was investigated by random amplification of polymorphic DNA-polymerase chain reaction. There is a high degree of genetic variation in all of the T. dimidiata populations as evidenced by high levels of average expected heterozygosity and polymorphism. Domestic populations are more closely related to each other (D = 0.05-0.085, Nei's genetic distance) than are the sylvan (D = 0.121-0.189). Within the limited sample size of three populations, there was a correlation with geographic and genetic distance for the domestic populations, but not for the sylvan. Surprisingly, one of the sylvan populations was genetically very similar to the domestic populations. The FST demonstrated a high degree of differentiation at the country-wide level (FST = 0.175) and a moderate degree of differentiation within the sylvan (FST = 0.135) or domestic (FST = 0.097) populations. Although these results demonstrated that gene flow is limited between different provinces in Guatemala, hierarchical analysis showed that barriers between the Atlantic and Pacific drainage slopes were not biologically significant limiters of gene flow.

The Chagas vector, Triatoma dimidiata (Hemiptera: Reduviidae), is panmictic within and among adjacent villages in Guatemala.

Trypanosoma cruzi, the hemoflagellate parasite and cause of Chagas disease in Latin America, is carried by Triatomine vectors, principally Triatoma dimidiata and Rhodnius prolixus in Central America. To assist control efforts and to understand the epidemiology of the disease in Guatemala, the population genetics of T. dimidiata was analyzed among three houses within a village and two adjacent villages in Guatemala. Eleven Randomly Amplified Polymorphic DNA-polymerase chain reaction (RAPD-PCR) primers were screened and three used to amplify bands, 29 of which were scored, from T. dimidiata DNA of approximately 50 bugs per house from three houses within a village and from 66 and 33 bugs, respectively, from adjacent villages. Results show very small genetic distances among the three T. dimidiata subpopulations from the houses (D = 0.013-0.022) and the two villages (D = 0.0199). The amount of differentiation among houses (fixation index, F(ST)) was also very small, F(ST) = 0.025 among the houses and the two villages F(ST) = 0.019. These fixation indices give an average number of mating migrants per generation (Nm) of 9.7 (among houses) and 12 (among villages). Average heterozygosity (H) appears to be high, ranging from H = 0.299-0.325 among the houses and H = 0.273 among the villages. The low genetic distance and fixation indices, and high heterozygosity suggest that the subpopulations in the houses and in the adjacent villages are not reproductively isolated but are in fact, one large panmictic population. Therefore the geographic coverage necessary for effective control must include, at least, the area encompassing adjacent villages.