134 research outputs found

    Genetic and chemical rescue of the Saccharomyces cerevisiae phenotype induced by mitochondrial DNA polymerase mutations associated with progressive external ophthalmoplegia in humans

    Get PDF
    The human POLG gene encodes the catalytic subunit of mitochondrial DNA polymerase γ (pol γ). Mutations in pol γ are associated with a spectrum of disease phenotypes including autosomal dominant and recessive forms of progressive external ophthalmoplegia, spino-cerebellar ataxia and epilepsy, and Alpers-Huttenlocher hepatocerebral poliodystrophy. Multiple deletions, or depletion of mtDNA in affected tissues, are the molecular hallmarks of pol γ mutations. To shed light on the pathogenic mechanisms leading to these phenotypes, we have introduced in MIP1, the yeast homologue of POLG, two mutations equivalent to the human Y955C and G268A mutations, which are associated with dominant and recessive PEO, respectively. Both mutations induced the generation of petite colonies, carrying either rearranged (ρ−) or no (ρ0) mtDNA. Mutations in genes that control the mitochondrial supply of deoxynucleotides (dNTP) affect the mtDNA integrity in both humans and yeast. To test whether the manipulation of the dNTP pool can modify the effects of pol γ mutations in yeast, we have overexpressed a dNTP checkpoint enzyme, ribonucleotide reductase, RNR1, or deleted its inhibitor, SML1. In both mutant strains, the petite mutability was dramatically reduced. The same result was obtained by exposing the mutant strains to dihydrolipoic acid, an anti-oxidant agent. Therefore, an increase of the mitochondrial dNTP pool and/or a decrease of reactive oxygen species can prevent the mtDNA damage induced by pol γ mutations in yeast and, possibly, in human

    Deciphering OPA1 mutations pathogenicity by combined analysis of human, mouse and yeast cell models

    Get PDF
    OPA1 is the major gene responsible for Dominant Optic Atrophy (DOA) and the syndromic form DOA “plus”. Over 370 OPA1 mutations have been identified so far, although their pathogenicity is not always clear. We have analyzed one novel and a set of known OPA1 mutations to investigate their impact on protein functions in primary skin fibroblasts and in two “ad hoc” generated cell systems: the MGM1/OPA1 chimera yeast model and the Opa1−/− MEFs model expressing the mutated human OPA1 isoform 1. The yeast model allowed us to confirm the deleterious effects of these mutations and to gain information on their dominance/recessivity. The MEFs model enhanced the phenotypic alteration caused by mutations, nicely correlating with the clinical severity observed in patients, and suggested that the DOA “plus” phenotype could be induced by the combinatorial effect of mitochondrial network fragmentation with variable degrees of mtDNA depletion. Overall, the two models proved to be valuable tools to functionally assess and define the deleterious mechanism and the pathogenicity of novel OPA1 mutations, and useful to testing new therapeutic interventions

    Deciphering OPA1 mutations pathogenicity by combined analysis of human, mouse and yeast cell models

    Get PDF
    OPA1 is the major gene responsible for Dominant Optic Atrophy (DOA) and the syndromic form DOA “plus”. Over 370 OPA1 mutations have been identified so far, although their pathogenicity is not always clear. We have analyzed one novel and a set of known OPA1 mutations to investigate their impact on protein functions in primary skin fibroblasts and in two “ad hoc” generated cell systems: the MGM1/OPA1 chimera yeast model and the Opa1−/− MEFs model expressing the mutated human OPA1 isoform 1. The yeast model allowed us to confirm the deleterious effects of these mutations and to gain information on their dominance/recessivity. The MEFs model enhanced the phenotypic alteration caused by mutations, nicely correlating with the clinical severity observed in patients, and suggested that the DOA “plus” phenotype could be induced by the combinatorial effect of mitochondrial network fragmentation with variable degrees of mtDNA depletion. Overall, the two models proved to be valuable tools to functionally assess and define the deleterious mechanism and the pathogenicity of novel OPA1 mutations, and useful to testing new therapeutic interventions

    Evaluation of humoral and cellular response to four vaccines against COVID-19 in different age groups: A longitudinal study

    Get PDF
    To date there has been limited head-to-head evaluation of immune responses to different types of COVID-19 vaccines. A real-world population-based longitudinal study was designed with the aim to define the magnitude and duration of immunity induced by each of four different COVID-19 vaccines available in Italy at the time of this study. Overall, 2497 individuals were enrolled at time of their first vaccination (T0). Vaccine-specific antibody responses induced over time by Comirnaty, Spikevax, Vaxzevria, Janssen Ad26.COV2.S and heterologous vaccination were compared up to six months after immunization. On a subset of Comirnaty vaccinees, serology data were correlated with the ability to neutralize a reference SARS-CoV-2 B strain, as well as Delta AY.4 and Omicron BA.1. The frequency of SARS-CoV-2-specific CD4+ T cells, CD8+ T cells, and memory B cells induced by the four different vaccines was assessed six months after the immunization. We found that mRNA vaccines are stronger inducer of anti-Spike IgG and B-memory cell responses. Humoral immune responses are lower in frail elderly subjects. Neutralization of the Delta AY.4 and Omicron BA.1 variants is severely impaired, especially in older individuals. Most vaccinees display a vaccine-specific T-cell memory six months after the vaccination. By describing the immunological response during the first phase of COVID-19 vaccination campaign in different cohorts and considering several aspects of the immunological response, this study allowed to collect key information that could facilitate the implementation of effective prevention and control measures against SARS-CoV-2

    Use of Telemedicine Healthcare Systems in Pediatric Assistance at Territorial Level: Consensus Document of the Italian Society of Telemedicine (SIT), of the Italian Society of Preventive and Social Pediatrics (SIPPS), of the Italian Society of Pediatric Primary Care (SICuPP), of the Italian Federation of Pediatric Doctors (FIMP) and of the Syndicate of Family Pediatrician Doctors (SIMPeF)

    Get PDF
    Technological innovation can contribute to a reorganization of healthcare, particularly by supporting the shift in the focus of care from the hospital to the territory, through innovative citizen-centered models, and facilitating access to services in the territory. Health and social care delivery modalities, enabled by telemedicine, are crucial in this regard. The objective of this Consensus document, written by the main Italian Scientific Societies involved in the use of telemedicine in pediatrics, is to define a standard for its use at the territorial level in various declinations in the pediatric field; this paper also identifies priority areas for its application and the types of services that most require intervention and investment. The changes that are underway in digital transformation in all sectors are unstoppable, and for the digital transformation to take place in a productive sense, the contribution of not only all health professionals, but also of patients, is necessary. From this perspective, authors from different backgrounds were involved in the drafting of this Consensus and, in the future, other figures, primarily patients, are expected to be involved. In fact, this belongs to the vision of connected care, in which the citizen/patient actively participates in the treatment path so that they are assisted in a personalized, predictive and preventive way. The future scenario must be able to provide for the involvement of patients from the initial stages of planning any treatment path, even in the pediatric age, and increasing, where possible, the proximity of the health service to the families

    Information and Training on the Use of Telemedicine in Pediatric Population: Consensus Document of the Italian Society of Telemedicine (SIT), of the Italian Society of Preventive and Social Pediatrics (SIPPS), of the Italian Society of Pediatric Primary Care (SICuPP), of the Italian Federation of Pediatric Doctors (FIMP), and of the Syndicate of Family Pediatrician Doctors (SIMPeF)

    Get PDF
    Telemedicine has entered the daily lives of doctors, although the digital skills of healthcare professionals still remain a goal to be achieved. For the purpose of a large-scale development of telemedicine, it is necessary to create trust in the services it can offer and to favor their acceptance by healthcare professionals and patients. In this context, information for the patient regarding the use of telemedicine, the benefits that can be derived from it, and the training of healthcare professionals and patients for the use of new technologies are fundamental aspects. This consensus document is a commentary that has the aim of defining the information on and training aspects of telemedicine for pediatric patients and their caregivers, as well as pediatricians and other health professionals who deal with minors. For the present and the future of digital healthcare, there is a need for a growth in the skills of professionals and a lifelong learning approach throughout the professional life. Therefore, information and training actions are important to guarantee the necessary professionalism and knowledge of the tools, as well as a good understanding of the interactive context in which they are used. Furthermore, medical skills can also be integrated with the skills of various professionals (engineers, physicists, statisticians, and mathematicians) to birth a new category of health professionals responsible for building new semiotics, identifying criteria for predictive models to be integrated into clinical practice, standardizing clinical and research databases, and defining the boundaries of social networks and new communication technologies within health services

    Use of Telemedicine Healthcare Systems in Pediatric Assistance at Territorial Level: Consensus Document of the Italian Society of Telemedicine (SIT), of the Italian Society of Preventive and Social Pediatrics (SIPPS), of the Italian Society of Pediatric Primary Care (SICuPP), of the Italian Federation of Pediatric Doctors (FIMP) and of the Syndicate of Family Pediatrician Doctors (SIMPeF)

    Get PDF
    Technological innovation can contribute to a reorganization of healthcare, particularly by supporting the shift in the focus of care from the hospital to the territory, through innovative citizen-centered models, and facilitating access to services in the territory. Health and social care delivery modalities, enabled by telemedicine, are crucial in this regard. The objective of this Consensus document, written by the main Italian Scientific Societies involved in the use of telemedicine in pediatrics, is to define a standard for its use at the territorial level in various declinations in the pediatric field; this paper also identifies priority areas for its application and the types of services that most require intervention and investment. The changes that are underway in digital transformation in all sectors are unstoppable, and for the digital transformation to take place in a productive sense, the contribution of not only all health professionals, but also of patients, is necessary. From this perspective, authors from different backgrounds were involved in the drafting of this Consensus and, in the future, other figures, primarily patients, are expected to be involved. In fact, this belongs to the vision of connected care, in which the citizen/patient actively participates in the treatment path so that they are assisted in a personalized, predictive and preventive way. The future scenario must be able to provide for the involvement of patients from the initial stages of planning any treatment path, even in the pediatric age, and increasing, where possible, the proximity of the health service to the families

    Use of Telemedicine Healthcare Systems in Children and Adolescents with Chronic Disease or in Transition Stages of Life: Consensus Document of the Italian Society of Telemedicine (SIT), of the Italian Society of Preventive and Social Pediatrics (SIPPS), of the Italian Society of Pediatric Primary Care (SICuPP), of the Italian Federation of Pediatric Doctors (FIMP) and of the Syndicate of Family Pediatrician Doctors (SIMPeF)

    Get PDF
    : Telemedicine is considered an excellent tool to support the daily and traditional practice of the health profession, especially when referring to the care and management of chronic patients. In a panorama in which chronic pathologies with childhood onset are constantly increasing and the improvement of treatments has allowed survival for them into adulthood, telemedicine and remote assistance are today considered effective and convenient solutions both for the chronic patient, who thus receives personalized and timely assistance, and for the doctors, who reduce the need for direct intervention, hospitalizations and consequent management costs. This Consensus document, written by the main Italian Scientific Societies involved in the use of telemedicine in pediatrics, has the objectives to propose an organizational model based on the relationships between the actors who participate in the provision of a telemedicine service aimed at minors with chronic pathologies, identifying specific project links between the areas of telemedicine in the developmental age from the first 1000 days of life to the age adult. The future scenario will have to be able to integrate digital innovation in order to offer the best care to patients and citizens. It will have to be able to provide the involvement of patients from the very beginning of the design of any care pathway, increasing where possible the proximity of the health service to citizens

    Guidelines for the use and interpretation of diagnostic methods in adult food allergy

    Get PDF
    Food allergy has an increasing prevalence in the general population and in Italy concerns 8 % of people with allergies. The spectrum of its clinical manifestations ranges from mild symptoms up to potentially fatal anaphylactic shock. A number of patients can be diagnosed easily by the use of first- and second-level procedures (history, skin tests and allergen specific IgE). Patients with complex presentation, such as multiple sensitizations and pollen-food syndromes, frequently require a third-level approach including molecular diagnostics, which enables the design of a component-resolved sensitization profile for each patient. The use of such techniques involves specialists' and experts' skills on the issue to appropriately meet the diagnostic and therapeutic needs of patients. Particularly, educational programs for allergists on the use and interpretation of molecular diagnostics are needed

    Overexpression of DNA Polymerase Zeta Reduces the Mitochondrial Mutability Caused by Pathological Mutations in DNA Polymerase Gamma in Yeast

    Get PDF
    In yeast, DNA polymerase zeta (Rev3 and Rev7) and Rev1, involved in the error-prone translesion synthesis during replication of nuclear DNA, localize also in mitochondria. We show that overexpression of Rev3 reduced the mtDNA extended mutability caused by a subclass of pathological mutations in Mip1, the yeast mitochondrial DNA polymerase orthologous to human Pol gamma. This beneficial effect was synergistic with the effect achieved by increasing the dNTPs pools. Since overexpression of Rev3 is detrimental for nuclear DNA mutability, we constructed a mutant Rev3 isoform unable to migrate into the nucleus: its overexpression reduced mtDNA mutability without increasing the nuclear one
    corecore