Origen de la vida basada en la complejidad biológica de los organismos: una revisión

Origin of life is an open scientific problem, and perhaps the largest mystery which has been formulated by humans. Approaching to alternative answers would give us relevant information about the evolution of modern sciences, biotechnology industry and even molecular medicine. Plausible evolutionary theories have been raised to solve the problem. Nevertheless, other ideas have been developed such as the one mentioned by A. Sharov and R. Gordon in their research job, named Life before Earth, whose main hypothesis indicates that life emerged before the formation of the Earth planet, based on the Moore´s Law and in thebiological complexity of organisms. The current paper shows a review of that work under the same basis, but calculating the biological complexity from the protein information of organisms far away from the context of the RNA world, since they are incompatible, with the calculus of an estimated date of the origin of life on Earth. Results show under referential purposes that life appeared years after the formation of our planet and not before, as is suggested in Life before Earth, evidencing that the date fits in the geological time scale chosen. The aforementioned offers an alternative reflection that contrasts what is known about the performance of earthy life and its evolution.El origen de la vida es un problema científico abierto, y tal vez la incógnita de mayor envergadura que se ha formulado el ser humano. Acercarse a respuestas alternativas aportaría información relevante para la evolución de las ciencias modernas, la industria biotecnológica e incluso la medicina molecular. Se han planteado plausibles teorías evolutivas que resuelven el problema; no obstante se han encontrado otras como la del trabajo de A. Sharov y R. Gordon denominado Life Before Earth, cuya principal hipótesis indica que la vida surgió antes de la formación del planeta tierra, basada en la ley de Moore y en la complejidad biológica de los organismos. El presente artículo presenta una revisión a dicho trabajo y, bajo los mismos fundamentos pero calculando la complejidad biológica a partir de la información proteínica de los organismos alejada del contexto del mundo del RNA pues no es compatible con el, se calcula una fecha aproximada para el origen de la vida en la tierra. Con propósitos referenciales, los resultados muestran que esta surgió años después de la formación del planeta y no antes como se sugiere en Life Before Earth, evidenciando que encaja en la escala temporal geológica escogida, y ofreciendo una reflexión alternativa que contrasta lo que se sabe del funcionamiento de la vida terrestre y su evolución

Italian politics in an era of recession : the end of bipolarism?

Italian politics have undergone momentous change in the 2007–2017 decade under the impact of the eurozone crisis, whose peak in 2011–2013 could be equated to the earlier watershed years of 1992–1994. The lasting impact of the upheaval in Italian politics in the early 1990s could still be felt in the decade of economic recession, but there were also new challenges prompted by a crisis that had its roots in international financial contagion and which unravelled under the shadow of both recession and austerity. The changes were of an economic, social, cultural, institutional, policy-oriented and political nature. If one central quintessentially political theme stands out by the end of this decade it is the apparent exhaustion of the quest for bipolarisation that was initiated in the early 1990s

Turnout and voting behaviour in constitutional referendums: a regional analysis of the Italian case

This paper investigates regional disparities of both turnout and voting behaviour in constitutional referendums. The analysis is undertaken at the NUTS-3 level and it considers the three constitutional referendums held in Italy in the period 2001–2016. It finds that turnout was lower in provinces with higher unemployment rates and where citizens had a stronger affiliation to opposition parties. These factors, along with level of government popularity, were important drivers of referendum results, especially in 2006 and 2016 when the referendums were rejected. In addition, while the three referendums implied different effects for rich and poor regions, mainly due to decentralization of powers, the local voting patterns did not reflect this. Overall, these findings suggest that the merit of the constitutional reforms played little part in explaining the outcome of the referendums

Long-term evaluation of coronary artery calcifications in kidney transplanted patients : a follow up of 5 years

Coronary artery calcifications(CACs), are related to the increased cardiovascular mortality during kidney transplantation(KTx). Using coronary-CT performed at 1 month(T0) and 5 years(T5) after KTx we evaluated: (1) the prevalence of CACs; (2) the clinical and biochemical factors related to CACs; 3) the factors implicated with CACs progression. We evaluated 67-pts selected from the 103-pts transplanted in our unit between 2007 and 2008. Clinical and biochemical parameters were recorded at the time of pre-KTx evaluation and for five years after KTx. Coronary-CT for the Agatson score (AS) evaluation was performed at T0 and at T5, and CACs progression was determined. At baseline AS was 45 [0-233]. At T5 AS was 119 [1-413]. At T0, 69% of patients had CACs. Age and dialytic vintage were the main independent variables related to CACs. At T5, CACs were present in 76% of patients. Age was the only independent factor in determining CACs. A progression of CACs was observed in 74% of patients. They were older, had higher CACs-T0 and higher SBP throughout the 5-years. The presence of CACs at T0 and age were the only independent factors in determining the CACs-progression. CACs-T0 had the best discriminative power for CACs progression. CACs prevalence is quite high in KTx patients; Age is strictly related to CACs; Age and the presence of CACs at baseline were the two major factors associated with the progression of CACs during the five years of follow up. CACs-T0 had the best discriminative power for progression of CACs

Organizing national responses for rare blood disorders: the Italian experience with sickle cell disease in childhood

Background Sickle cell disease (SCD) is the most frequent hemoglobinopathy worldwide but remains a rare blood disorder in most western countries. Recommendations for standard of care have been produced in the United States, the United Kingdom and France, where this disease is relatively frequent because of earlier immigration from Africa. These recommendations have changed the clinical course of SCD but can be difficult to apply in other contexts. The Italian Association of Pediatric Hematology Oncology (AIEOP) decided to develop a common national response to the rising number of SCD patients in Italy with the following objectives: 1) to create a national working group focused on pediatric SCD, and 2) to develop tailored guidelines for the management of SCD that could be accessed and practiced by those involved in the care of children with SCD in Italy. Methods Guidelines, adapted to the Italian social context and health system, were developed by 22 pediatric hematologists representing 54 AIEOP centers across Italy. The group met five times for a total of 128 hours in 22 months; documents and opinions were circulated via web. Results Recommendations regarding the prevention and treatment of the most relevant complications of SCD in childhood adapted to the Italian context and health system were produced. For each topic, a pathway of diagnosis and care is detailed, and a selection of health management issues crucial to Italy or different from other countries is described (i.e., use of alternatives for infection prophylaxis because of the lack of oral penicillin in Italy). Conclusions Creating a network of physicians involved in the day-to-day care of children with SCD is feasible in a country where it remains rare. Providing hematologists, primary and secondary care physicians, and caregivers across the country with web-based guidelines for the management of SCD tailored to the Italian context is the first step in building a sustainable response to a rare but emerging childhood blood disorder and in implementing the World Health Organization\u2019s suggestion \u201cto design (and) implement \u2026 comprehensive national integrated programs for the prevention and management of SCD"

Identification and comparative analysis of components from the signal recognition particle in protozoa and fungi

BACKGROUND: The signal recognition particle (SRP) is a ribonucleoprotein complex responsible for targeting proteins to the ER membrane. The SRP of metazoans is well characterized and composed of an RNA molecule and six polypeptides. The particle is organized into the S and Alu domains. The Alu domain has a translational arrest function and consists of the SRP9 and SRP14 proteins bound to the terminal regions of the SRP RNA. So far, our understanding of the SRP and its evolution in lower eukaryotes such as protozoa and yeasts has been limited. However, genome sequences of such organisms have recently become available, and we have now analyzed this information with respect to genes encoding SRP components. RESULTS: A number of SRP RNA and SRP protein genes were identified by an analysis of genomes of protozoa and fungi. The sequences and secondary structures of the Alu portion of the RNA were found to be highly variable. Furthermore, proteins SRP9/14 appeared to be absent in certain species. Comparative analysis of the SRP RNAs from different Saccharomyces species resulted in models which contain features shared between all SRP RNAs, but also a new secondary structure element in SRP RNA helix 5. Protein SRP21, previously thought to be present only in Saccharomyces, was shown to be a constituent of additional fungal genomes. Furthermore, SRP21 was found to be related to metazoan and plant SRP9, suggesting that the two proteins are functionally related. CONCLUSIONS: Analysis of a number of not previously annotated SRP components show that the SRP Alu domain is subject to a more rapid evolution than the other parts of the molecule. For instance, the RNA portion is highly variable and the protein SRP9 seems to have evolved into the SRP21 protein in fungi. In addition, we identified a secondary structure element in the Sacccharomyces RNA that has been inserted close to the Alu region. Together, these results provide important clues as to the structure, function and evolution of SRP

A digital waveguide-based approach for Clavinet modeling and synthesis

The Clavinet is an electromechanical musical instrument produced in the mid-twentieth century. As is the case for other vintage instruments, it is subject to aging and requires great effort to be maintained or restored. This paper reports analyses conducted on a Hohner Clavinet D6 and proposes a computational model to faithfully reproduce the Clavinet sound in real time, from tone generation to the emulation of the electronic components. The string excitation signal model is physically inspired and represents a cheap solution in terms of both computational resources and especially memory requirements (compared, e.g., to sample playback systems). Pickups and amplifier models have been implemented which enhance the natural character of the sound with respect to previous work. A model has been implemented on a real-time software platform, Pure Data, capable of a 10-voice polyphony with low latency on an embedded device. Finally, subjective listening tests conducted using the current model are compared to previous tests showing slightly improved results

Genome Structure of the Legume, Lotus japonicus

The legume Lotus japonicus has been widely used as a model system to investigate the genetic background of legume-specific phenomena such as symbiotic nitrogen fixation. Here, we report structural features of the L. japonicus genome. The 315.1-Mb sequences determined in this and previous studies correspond to 67% of the genome (472 Mb), and are likely to cover 91.3% of the gene space. Linkage mapping anchored 130-Mb sequences onto the six linkage groups. A total of 10 951 complete and 19 848 partial structures of protein-encoding genes were assigned to the genome. Comparative analysis of these genes revealed the expansion of several functional domains and gene families that are characteristic of L. japonicus. Synteny analysis detected traces of whole-genome duplication and the presence of synteny blocks with other plant genomes to various degrees. This study provides the first opportunity to look into the complex and unique genetic system of legumes

Evolutionary Convergence and Nitrogen Metabolism in Blattabacterium strain Bge, Primary Endosymbiont of the Cockroach Blattella germanica

Bacterial endosymbionts of insects play a central role in upgrading the diet of their hosts. In certain cases, such as aphids and tsetse flies, endosymbionts complement the metabolic capacity of hosts living on nutrient-deficient diets, while the bacteria harbored by omnivorous carpenter ants are involved in nitrogen recycling. In this study, we describe the genome sequence and inferred metabolism of Blattabacterium strain Bge, the primary Flavobacteria endosymbiont of the omnivorous German cockroach Blattella germanica. Through comparative genomics with other insect endosymbionts and free-living Flavobacteria we reveal that Blattabacterium strain Bge shares the same distribution of functional gene categories only with Blochmannia strains, the primary Gamma-Proteobacteria endosymbiont of carpenter ants. This is a remarkable example of evolutionary convergence during the symbiotic process, involving very distant phylogenetic bacterial taxa within hosts feeding on similar diets. Despite this similarity, different nitrogen economy strategies have emerged in each case. Both bacterial endosymbionts code for urease but display different metabolic functions: Blochmannia strains produce ammonia from dietary urea and then use it as a source of nitrogen, whereas Blattabacterium strain Bge codes for the complete urea cycle that, in combination with urease, produces ammonia as an end product. Not only does the cockroach endosymbiont play an essential role in nutrient supply to the host, but also in the catabolic use of amino acids and nitrogen excretion, as strongly suggested by the stoichiometric analysis of the inferred metabolic network. Here, we explain the metabolic reasons underlying the enigmatic return of cockroaches to the ancestral ammonotelic state