Inbreeding and Genetic Erosion from a Finite Model of a Synthetic Formed with Single Crosses.

When a seed produced by a single-cross (SC) maize hybrid is sown, the resulting grain yield is usually lower than that of the hybrid due to the inbreeding generated. However, if a seed from a mixture of s hybrids were sown instead, the synthetic variety thus formed (SynSC) would have a lower inbreeding coefficient (FSynSC) and a higher grain yield. The grain yield s, the finite number of representatives of each parent SC (m) and the inbreeding coefficient of the parent lines of the SCs (F) are related to the FSynSC. In addition, randomness and the finite size of m can cause the loss of genes and genotypes and increase the FSynSC. The objectives of this study were to derive formulas for (1) expressing FSynSC in terms of m, F, and s, and (2) calculating the probability of the occurrence of gene and genotype loss. It was found that for the probability of no genotype being missing from the progeny representing a parent to be at least 0.95, it is necessary that m ≥ 15. It was also found that a sample size of 7 is sufficient for FSynSC to stabilize, more visibly as F is larger, and for the probability of the occurrence of erosion to be practically zero.

Haploid Induction in Tomato (Solanum lycopersicum L.) via Gynogenesis.

The generation of new hybrid varieties of tomato (Solanum lycopersicum L.) is the most widely used breeding method for this species and requires at least seven self-fertilization cycles to generate stable parent lines. The development of doubled haploids aims at obtaining completely homozygous lines in a single generation, although, to date, routine commercial application has not been possible in this species. In contrast, obtaining doubled haploid lines via gynogenesis has been successfully implemented in recalcitrant crops such as melon, cucumber, pumpkin, loquat and walnut. This review provides an overview of the requirements and advantages of gynogenesis as an inducer of haploidy in different agricultural crops, with the purpose of assessing the potential for its application in tomato breeding. Successful cases of gynogenesis variants involving in vitro culture of unfertilized ovules, use of 60Co-irradiated pollen, in vivo haploid inducers and wide hybridization are presented, suggesting that these methodologies could be implemented in tomato breeding programs to obtain doubled haploids.

Distribution and Climatic Adaptation of Wild Tomato (Solanum lycopersicum L.) Populations in Mexico.

Tomato (Solanum lycopersicum L.) is a vegetable with worldwide importance. Its wild or close related species are reservoirs of genes with potential use for the generation of varieties tolerant or resistant to specific biotic and abiotic factors. The objective was to determine the geographic distribution, ecological descriptors, and patterns of diversity and adaptation of 1296 accessions of native tomato from Mexico. An environmental information system was created with 21 climatic variables with a 1 km2 spatial resolution. Using multivariate techniques (Principal Component Analysis, PCA; Cluster Analysis, CA) and Geographic Information Systems (GIS), the most relevant variables for accession distribution were identified, as well as the groups formed according to the environmental similarity among these. PCA determined that with the first three PCs (Principal Components), it is possible to explain 84.1% of the total variation. The most relevant information corresponded to seasonal variables of temperature and precipitation. CA revealed five statistically significant clusters. Ecological descriptors were determined and described by classifying accessions in Physiographic Provinces. Temperate climates were the most frequent among tomato accessions. Finally, the potential distribution was determined with the Maxent model with 10 replicates by cross-validation, identifying areas with a high probability of tomato presence. These results constitute a reliable source of useful information for planning accession sites collection and identifying accessions that are vulnerable or susceptible to conservation programs.

Climatic Diversity and Ecological Descriptors of Wild Tomato Species (Solanum sect. Lycopersicon) and Close Related Species (Solanum sect. Juglandifolia y sect. Lycopersicoides) in Latin America.

Conservation and sustainable use of species diversity require a description of the environment where they develop. The objectives were to determine ecological descriptors and climatic diversity of areas along the distribution range of 12 species of wild tomatoes (Solanum sect. Lycopersicon) and four wild species of phylogenetically related groups (Solanum sect. Juglandifolia and sect. Lycopersicoides), as well as their ecological similarity in Latin America. With 4228 selected tomato accessions and an environmental information system (EIS) composed of 21 climatic variables, diversity patterns of the distribution areas were identified for each species, as well as ecological descriptors through the use of geographic information systems (GIS). The contribution of climatic variables to the species geographical distribution was identified by principal component analysis (PCA), and similarity in species distribution as a function of the variables identified with cluster analysis (CA). Climatic characteristics and the environmental amplitude of wild tomatoes and related species along their distributional range were satisfactorily determined by ecological descriptors. Eleven climate types were identified, predominantly BSk (arid, steppe, cold), BWh (arid, desert, hot), and Cfb (temperate, no dry season, warm summer). PCA determined 10 most important variables were the most important for the geographical distribution. Six groups of species were identified according to CA and climatic distribution similarity. This approach has shown promissory applications for biodiversity conservation of valuable genetic resources for tomato crop breeding.

Edaphoclimatic Descriptors of Wild Tomato Species (Solanum Sect. Lycopersicon) and Closely Related Species (Solanum Sect. Juglandifolia and Sect. Lycopersicoides) in South America.

Wild species related to cultivated tomato are essential genetic resources in breeding programs focused on food security to face future challenges. The ecogeographic analysis allows identifying the species adaptive ranges and most relevant environmental variables explaining their patterns of actual distribution. The objective of this research was to identify the diversity, ecological descriptors, and statistical relationship of 35 edaphoclimatic variables (20 climatic, 1 geographic and 14 edaphic variables) from 4,649 accessions of 12 wild tomato species and 4 closely related species classified in Solanum sect. Lycopersicon and clustered into four phylogenetic groups, namely "Lycopersicon group" (S. pimpinellifolium, S. cheesmaniae, and S. galapagense), "Arcanum group" (S. arcanum, S. chmielewskii, and S. neorickii), "Eriopersicon group" (S. habrochaites, S. huaylasense, S. corneliomulleri, S. peruvianum, and S. chilense), "Neolycopersicon group" (S. pennellii); and two phylogenetically related groups in Solanum sect. Juglandifolia (S. juglandifolium and S. ochranthum), and section Lycopersicoides (S. lycopersicoides and S. sitiens). The relationship between the climate and edaphic variables were determined by the canonical correlation analysis, reaching 89.2% of variation with the first three canonical correlations. The most significant climatic variables were related to humidity (annual evapotranspiration, annual precipitation, and precipitation of driest month) and physicochemical soil characteristics (bulk density, pH, and base saturation percentage). In all groups, ecological descriptors and diversity patterns were consistent with previous reports. Regarding edaphoclimatic diversity, 12 climate types and 17 soil units were identified among all species. This approach has promissory applications for biodiversity conservation and uses valuable genetic resources related to a leading crop.

Barbagli's dorsal urethroplasty. Analysis of results and factors for success.

OBJECTIVES: Dorsal urethroplasty as described by Barbagli has gained wide acceptance in the treatment of urethral stricture, given the simplification afforded by obtaining a free graft versus a flap. We present a series of 50 patients treated in our department of urethral stricture by dorsal onlay free graft urethroplasty (Barbagli's technique), in combination or not to other techniques in more complex strictures. METHODS: The average age of patients was 48.8 years (23-77), the mean follow up 42.9 months (12-96) and the most frequently observed etiology has been the inflammatory urethral stricture (50%). RESULTS: Overall success rate was 82% (41 cases) and failure 18% (9 cases). In the longer follow-up group, there was a slight drop in success rate of 80% (24 cases) without any significant differences between groups (p= 0.9). Analyzing the variables length of free graft (p= 0.50, p> 36= 0.53), age (p= 0.12, p>36= 0.59), etiology of stricture (p= 0.77, p>36 = 0.77) and type of graft used (p=0.24, p>36= 0.38) did not show any influence on the final outcome of surgery, both in the total sample and the subgroup with follow-up > 36 months. The location of the stricture in bulbar urethra has shown better functional outcome than those operated on for strictures affecting also other urethral locations (p= 0.001) maintaining that result in the group of longer follow up (p>36= 0,001). The lack of treatment prior to urethral surgery has influenced the success of it, since 90.6% of patients without prior treatment before urethroplasty have seen a good functional outcome, compared to treatment prior to surgery that obtained a 66.7% (p= 0.03). This significance is also demonstrated in the group of follow-up > 36 months (p>36= 0.01). CONCLUSION: The dorsal onlay free graft urethroplasty is a versatile and reproducible technique with acceptable results which allows combination with other techniques when the stenosis extends to the penile urethra. In exceptional cases of panurethral strictures secondary to lichen sclerosus when there is no significant spongiofibrosis and an acceptable urethral plate, can be applied to the whole urethra.

Manejo de primera crisis afebril: Importancia del enfoque clínico / Management of first nonfebrile seizure: Importance of clinical approach

Una crisis epiléptica es un evento traumático físico como psicológico que plantea dificultades en el diagnóstico y muchas interrogantes para el tratamiento agudo y en el largo plazo. La recurrencia de una crisis epiléptica origina aún más serios y costosos problemas en la vida personal, familiar y laboral del individuo afectado. En estas circunstancias, un correcto abordaje del manejo de individuos con una primera crisis afebril debe ser una prioridad de los sistemas de salud con el objetivo fundamental de prevención de recurrencias. La elección de un fármaco antiepiléptico va a depender de una detallada anamnesis del evento clínico y de la información proveniente de estudios o tests neurofisiológicos y por exámenes de imágenes cerebrales.

Seizures or an epileptic crisis is a traumatic event, both of physical and psychological nature that poses difficulties in the diagnostic process and many questions for its immediate and long-term management. The recurrence of an epileptic crisis causes even more serious and costly problems in the personal, family and work life of the affected individual. Due to this, a correct approach to the management of patients with a first afebrile crisis must be a priority of the health systems, with the primary purpose of preventing recurrences. The choice of an anti-epileptic drug will depend on a detailed anamnesis of the clinical event and onthe information from neurophysiological tests and brain imaging studies.

Uretroplastia dorsal según técnica de Barbagli. Análisis de resultados y factores de éxito / Barbagli`s dorsal urethroplasty. Analysis of results and factors for success

OBJETIVO: La uretroplastia dorsal descrita por Barbagli ha ganado amplia aceptación en el tratamiento de la estenosis de uretra, dada la simplificación que otorga la obtención del injerto libre frente a los pediculados.Presentamos una serie de 50 casos intervenidos en nuestro servicio de estenosis de uretra mediante uretroplastia dorsal con injerto libre (técnica de Barbagli), asociado o no a otras tecnicas en estenosis mas complejas.MÉTODOS: La edad media de los pacientes ha sido de 48.8 años (23-77), el tiempo de seguimiento medio de 42.9 meses (12-96) y la etiología más observada ha sido la estenosis uretral inflamatoria (50%).RESULTADOS: La tasa global de éxito ha sido del 82% (41 casos) y la de fracaso 18% (9 casos). En el grupo de mayor seguimiento, se observa un leve descenso de la tasa de éxito del 80% (24 casos) sin que se aprecien diferencias entre ambos grupos (p=0.98).El análisis de las variables longitud del injerto (p=0.50; p>36=0.53), edad (p= 0.12; p>36=0.59), etiología de la estenosis (p=0.77; p>36=0.77) y tipo de injerto utilizado (p=0.24; p>36=0.38), no demostraron ejercer influencia alguna en el resultado final de la cirugía, tanto en el total de la muestra como en el subgrupo de seguimiento >36 meses.La localización de la estenosis en uretra bulbar ha demostrado mejor resultado funcional que los intervenidos por estenosis que afectaban además a otras zonas de la uretra (p= 0.001) manteniéndose dicho resultado en el grupo de mayor seguimiento (p>36=0.001).La ausencia de tratamiento previo a la cirugía uretral ha influenciado el éxito de la misma, ya que el 90.6% de pacientes sin tratamiento anterior a la uretroplastia han observado un buen resultado funcional frente al grupo de tratamiento previo a cirugía que lo ha obtenido en un 66.7% (p=0.03). Esta significación también se demuestra en el grupo de 36 meses (p>36 = 0.01)(AU)

CONCLUSIÓN: La uretroplastia dorsal con injerto libre es una técnica versátil y reproducible con unos resultados aceptables que permite su asociación a otras técnicas cuando la estenosis se extiende a la uretra peneana(AU)

OBJECTIVES: Dorsal urethroplasty as described by Barbagli has gained wide acceptance in the treatment of urethral stricture, given the simplification afforded by obtaining a free graft versus a flap.We present a series of 50 patients treated in our de-partment of urethral stricture by dorsal onlay free graft urethroplasty (Barbagli’s technique), in combination or not to other techniques in more complex strictures.METHODS: The average age of patients was 48.8 years (23-77), the mean follow up 42.9 months (12-96) and the most frequently observed etiology has been the inflammatory urethral stricture (50%).RESULTS: Overall success rate was 82% (41 cases) and failure 18% (9 cases). In the longer follow-up group, there was a slight drop in success rate of 80% (24 ca-ses) without any significant differences between groups (p= 0.98).Analyzing the variables length of free graft (p= 0.50, p> 36= 0.53), age (p= 0.12, p>36= 0.59), etiology of stricture (p= 0.77, p>36 = 0.77) and type of graft used (p=0.24, p>36= 0.38) did not show any influence on the final outcome of surgery, both in the total sample and the subgroup with follow-up > 36 months.The location of the stricture in bulbar urethra has shown better functional outcome than those operated on for stric-tures affecting also other urethral locations (p= 0.001) maintaining that result in the group of longer follow up (p>36= 0,001).The lack of treatment prior to urethral surgery has influen-ced the success of it, since 90.6% of patients without prior treatment before urethroplasty have seen a good func-tional outcome, compared to treatment prior to surgery that obtained a 66.7% (p= 0.03). This significance is also demonstrated in the group of follow-up > 36 months (p>36= 0.01)(AU)

CONCLUSION: The dorsal onlay free graft urethroplas-ty is a versatile and reproducible technique with accep-table results which allows combination with other tech-niques when the stenosis extends to the penile urethra. In exceptional cases of panurethral strictures secondary to lichen sclerosus when there is no significant spongiofi-brosis and an acceptable urethral plate, can be applied to the whole urethra(AU)

Litiasis múltiples en neovejiga tipo Hautmann / Multiple lithiasis in Hautmann neobladder

No disponible

Cuerpo extraño intraureteral / Intraurethral foreign body

No disponible