Exploring the use of wild relatives in potato breeding through integrated cytogenetic and genomic approaches

Cultivated potato and its wild relatives represent a more diverse and accessible germplasm resource than that of any other crop. Diversity coming from wild relatives can be used to introduce specific traits into the cultivated background. Breeders have long used introgressive hybridization, in which chromatin carrying a gene of interest from a wild relative is integrated into the genome of the crop by interspecific hybridization. During the subsequent backcrossing generations, genes of interest are incorporated into the crop chromosomes by homeologous recombination. The offspring are then selected for the desired trait while the original cultivated genetic background is recovered by backcrossing and selection as far as possible. The efficient use of wild relatives now requires extensive knowledge of their allelic variation and genomic structure, including the screening for desirable traits. To minimize the occurrence of linkage drag when introgressed chromatin still contains closely linked wild traits from the ancestral donor, knowledge on the genomic structure of crop and donor species is indispensable. In this work I have presented an overview of genetic, cytogenetic and genomic characteristics of Solanum commersonii, a South American wild relative of potato. The main aim was to create scientific tools to distinguish the genomes of S. commersonii and S. tuberosum (cultivated potato), along with S. chacoense, and trace their genomes in introgressive hybridization breeding programmes. The application of these tools to pinpoint past introgressions into cultivated potato and to plan introgressive hybridization schemes is reviewed in Chapter 2, with an emphasis on the need to make these technologies part of the routine toolkit for pre-breeding in order to exploit potato wild relatives at their fullest. A variety of questions related to the use of particular potato wild relatives in introgression are addressed using different cytogenetic and genomic technologies. In Chapter 3 pairing of the homoeologous S. commersonii genomes and S. tuberosum Group Phureja chromosomes in F1 interspecific triploid hybrids was analyzed, observing an almost autotriploid behaviour. Genome painting was used to follow the fate of specific chromosomes in these hybrids and backcross derivatives. Homoeologues could not be distinguished by fluorescence signals, so this approach did not provide tools to select against wild chromatin in the advanced materials nor pinpoint the chromosomal exchanges between homoeologues. However, the results suggest a low degree of genomic divergence between the species involved in terms of repetitive sequences and highlight their potential for homoeologous pairing. A comparative cytogenetic mapping analysis was performed in Chapter 4, to test collinearity among genomes of the different species and thus anticipate the existence of either suppression of recombination or linkage drag. Solanum commersonii and S. chacoense are collinear with cultivated S. tuberosum on the whole chromosome scale. Some differences observed in microscopic distances between the signals suggest either small-scale rearrangements or reduction/amplification of repetitive sequences. No major rearrangements have been found, making these amenable species for efficient introgressive hybridization breeding. In Chapter 5 we looked at the repetitive fraction of the genomes of potato and its wild relatives compared to tomato and its wild relatives, to elucidate if the differences in genome differentiation observed among the clades can be correlated to different dynamics in repetitive elements. Using a clustering approach with short read data, we found that the classes of repetitive elements across the clades are largely conserved, but their abundances are different and the repeat profiles allowed us to discriminate the two clades. We also found that the repeat content of S. etuberosum is more similar overall to the potato clade. All these tools provide information about possible crossability among these species in terms of their genome similarity and collinearity in chromosome structure. However, the possibility of small-scale differences required a look at synteny at the sequence level. The main challenge to be addressed in Chapter 6 was to achieve a contiguous de novo assembly that would allow for structural comparison, from the genome of a highly heterozygous plant. This was solved by sequencing a haploid clone obtained through in vitro culture of microspores and by taking a hybrid approach to the assembly, integrating short Illumina reads with much longer PacBio sequence data. A genetic map was developed using SNP data generated through GBS from a biparental segregating population. Then the hybrid assembly was anchored to the linkage map into 12 pseudomolecules built independently from any reference genome. The 12 pseudomolecules showed high overall homology with the DM potato and M6 S. chacoense pseudomolecules, with the order of scaffolds homologous among the three species. However, contiguity is lost in the pericentromere region and therefore, lack of collinearity is observed here. Small-scale rearrangements could not be conclusively distinguished from assembly or anchoring artifacts, with a few exceptions. In general terms, there is need for further improvement of contiguity and manual correction of the orientation of scaffolds in order to unequivocally detect rearrangements at the microsynteny scale. This can be achieved by using Bionano genome mapping and/or chromatin conformation capture technologies in the near future. To apply these technologies, extremely pure High Molecular Weight (HMW) DNA is necessary, so in Chapter 7 we adapted a pre-existing HMW DNA isolation protocol to optimize it for Solanum species. The results presented here address the doubts that have discouraged potato pre-breeders to use Solanum commersonii and S. chacoense in introgressive hybridization breeding. These species can be crossed with diploid potato producing viable offspring that can be used in backcrosses with cultivated potato. Wild chromosomes pair and recombine with their cultivated homoeologues, making introgression possible. These species are highly collinear at the large and small scale and their genomes have not diverged much both at the level of repetitive sequences and at the level of synteny. With the advent of diploid potato breeding, these species are particularly promising because of their traits, diversity and their adaptability and hardiness, but also because of their high similarity with potato from the genetic, cytogenetic and genomic points of view.</p

Misión comercial a la India. Una experiencia de aprendizaje situado

La experiencia educativa Misión comercial a la India se desarrolló en un entorno de aula virtual online a través de la cual los estudiantes pudieron participar en una misión comercial en tiempo real posibilitando vivenciar y experimentar un viaje de negocios como si cada uno de ellos lo estuviese haciendo en persona. Este texto presenta de manera reflexiva, el relato de la experiencia, los fundamentos pedagógicos y didácticos desde los cuales se pensó la propuesta, las estrategias y los recursos que se utilizaron, el papel de los contenidos, la reconfiguración de las actividades, los tiempos y los escenarios de la enseñanza y del aprendizaje y los desafíos y las incertidumbres que se fueron enfrentando en el desarrollo de esta innovadora y creativa experiencia en la que todos los participantes resultaron enseñantes y aprendices.Trabajo publicado en Giordano, Carlos José y Morandi, Glenda (comps.). Memorias de las 2º Jornadas sobre las Prácticas Docentes en la Universidad Pública. La enseñanza universitaria a 100 años de la reforma: legados, transformaciones y compromisos. Universidad Nacional de La Plata: La Plata, 2019.Presidenci

Misión comercial a la India. Una experiencia de aprendizaje situado

La experiencia educativa Misión comercial a la India se desarrolló en un entorno de aula virtual online a través de la cual los estudiantes pudieron participar en una misión comercial en tiempo real posibilitando vivenciar y experimentar un viaje de negocios como si cada uno de ellos lo estuviese haciendo en persona. Este texto presenta de manera reflexiva, el relato de la experiencia, los fundamentos pedagógicos y didácticos desde los cuales se pensó la propuesta, las estrategias y los recursos que se utilizaron, el papel de los contenidos, la reconfiguración de las actividades, los tiempos y los escenarios de la enseñanza y del aprendizaje y los desafíos y las incertidumbres que se fueron enfrentando en el desarrollo de esta innovadora y creativa experiencia en la que todos los participantes resultaron enseñantes y aprendices.Trabajo publicado en Giordano, Carlos José y Morandi, Glenda (comps.). Memorias de las 2º Jornadas sobre las Prácticas Docentes en la Universidad Pública. La enseñanza universitaria a 100 años de la reforma: legados, transformaciones y compromisos. Universidad Nacional de La Plata: La Plata, 2019.Presidenci

Misión comercial a la India. Una experiencia de aprendizaje situado

La experiencia educativa Misión comercial a la India se desarrolló en un entorno de aula virtual online a través de la cual los estudiantes pudieron participar en una misión comercial en tiempo real posibilitando vivenciar y experimentar un viaje de negocios como si cada uno de ellos lo estuviese haciendo en persona. Este texto presenta de manera reflexiva, el relato de la experiencia, los fundamentos pedagógicos y didácticos desde los cuales se pensó la propuesta, las estrategias y los recursos que se utilizaron, el papel de los contenidos, la reconfiguración de las actividades, los tiempos y los escenarios de la enseñanza y del aprendizaje y los desafíos y las incertidumbres que se fueron enfrentando en el desarrollo de esta innovadora y creativa experiencia en la que todos los participantes resultaron enseñantes y aprendices.Trabajo publicado en Giordano, Carlos José y Morandi, Glenda (comps.). Memorias de las 2º Jornadas sobre las Prácticas Docentes en la Universidad Pública. La enseñanza universitaria a 100 años de la reforma: legados, transformaciones y compromisos. Universidad Nacional de La Plata: La Plata, 2019.Presidenci

Hospital de pediatría de Tandil

El llamado a concurso tuvo por objeto el desarrollo del proyecto para construir el hospital de pediatría, tomando como base las actuales instalaciones de las dependencias de salud mental del municipio, alojadas en la manzana contigua al hospital central.Facultad de Arquitectura y Urbanism

Efficacy of a low-dose diosmin therapy on improving symptoms and quality of life in patients with chronic venous disease. Randomized, double-blind, placebo-controlled trial

Chronic Venous Disease (CVD) is a common medical condition affecting up to 80% of the general population. Clinical manifestations can range from mild to more severe signs and symptoms that contribute to the impairment of the quality of life (QoL) of affected patients. Among treatment options, venoactive drugs such as diosmin are widely used in the symptomatic treatment in all clinical stages. The aim of this study is to determine the effectiveness of a new formulated diosmin in relieving symptoms and improving QoL in patients suffering from CVD. In this randomized, double-blind, placebo-controlled, multicenter clinical study, CVD patients with a Clinical-Etiology-Anatomy-Pathophysiology (CEAP) classification system between C2 and C4 were randomized to receive a bioavailable diosmin (as μsmin® Plus) 450 mg tablet once daily or a placebo for 8 weeks. Clinical symptoms and QoL were monitored using the measurement of leg circumference, visual analogue scale (VAS) for pain, Global Index Score (GIS) and Venous Clinical Severity Score (VCSS). A total of 72 subjects completed the study. From week 4, leg edema was significantly decreased in the active group (p &lt; 0.001). An improvement in the VAS score was observed in the active group compared to placebo at the end of treatment (p &lt; 0.05). GIS and VCSS scores were significantly improved in the active group at week 8 (p &lt; 0.001). No treatment related-side effects were recorded. The results of this study showed that the administration of low-dose μsmin® Plus was safe and effective in relieving symptoms and improving QoL in subjects with CVD

Well-being among Italian medical oncologists: An exploratory study

Background: Recently, attention has been focused on physicians' stress and quality-of-life improvement. Due to their relationship with patients, oncologists in particular are overloaded physically, emotionally and psychologically. Previous studies showed that training of communication skills improves the satisfaction and well-being of physicians and patients. Aims: Our research investigates the relationship between work stress and engagement and personal well-being in physicians working in Italian hospitals. Materials and Methods: 176 physicians were included. Doctors filled out self-report questionnaires to evaluate work stress and coping strategies, personal well-being, work engagement and two purpose-built scales to measure the degree of perceived organizational support and the level of specific training of social and relational skills. Descriptive statistics were used to analyze data, as well as correlation analysis (Pearson's r), hierarchical regression analysis (enter step) and analysis of variance (one-way ANOVA). Result: Positive and significant correlations were found between variables. Moreover, physicians who obtained higher levels of specific training on social and relational skills reported lower levels of stress. Oncologists experienced greater stress than other physicians in terms of maladaptive coping and lack of additional training. Conclusions: The study suggests that physicians' well-being is mediated by professional aspects, such as social skills in relationships with patients.M