The role of proteasome dysfunction in the mechanisms of motor neuron degeneration in a mouse model of familial amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by the loss of the motor neurons. One consistent neuropathological feature of ALS patients and models of the disease is the formation of proteinaceous inclusion bodies; for this reason, alterations in the proteolytic ubiquitin-proteasome pathway (UPP) have been suggested to be implicated. The purpose of this thesis was to analyze the role of the UPP in ALS pathogenesis studying the G93A mouse model. The activity of UPP was evaluated in G93A mice carrying the UbG76V-GFP reporter protein for proteasomal functionality. Furthermore, the expression of different constitutive proteasome and immunoproteasome subunits was measured during disease progression. In symptomatic G93A lumbar spinal cord, a mild increase of UbG76V-GFP protein, but not of its transcript, was found in the motor neuronal population and was partly associated with high levels of ubiquitin and perikarial presence of phosphorylated neurofilaments. At the end stage, the increase of the reporter protein was prevalent in other neurons besides motor neurons, but also the mRNA levels were augmented. Constitutive catalytic subunits of the 20S proteasome were reduced in end stage G93A lumbar spinal cord, while an increase of their inducible counterparts and a decrease of the non-catalytic as subunit were evident at the symptomatic phase. Components of 19S and 11S complexes were significantly reduced prior to symptom onset. The changes in proteasome composition were accompanied by a substantial increase of glial markers and TNFα. Altogether, these data suggest that a subtle dysfunction of the ubiquitin-proteasome pathway occurs in the spinal cord of a mouse model of ALS in a phase in which the first signs of motor impairment are detectable. This pairs with alterations in the transcriptional rate of various proteasome subunits, resulting in a decrease of constitutive proteasome and an increase of immunoproteasome

Ing. Óscar J. Maggiolo : el combate por una política nacional autónoma en ciencia y tecnología

Por su múltiple personalidad intelectual, la amplitud de su solidaria vocación social, su compromiso con el movimiento universitario reformista latinoamericano, su innegable capacidad innovadora en el plano profesional y su altiva conducta política de denuncia y combate contra la dictadura, al ingeniero Óscar J. Maggiolo se lo debe valorar como un hombre a quien «nada de lo humano le fue ajeno». Maggiolo exploró una diversidad de regiones, fueran ellas profesionales, académicas o de política universitaria, nacional o internacional, siempre lo hizo con rigor científico, responsabilidad social y sin eludir el compromiso político

ESTUDO SOBRE A FELICIDADE E OS IMPACTOS DA PANDEMIA DA COVID-19: CONTRIBUIÇÕES DA ECONOMIA COMPORTAMENTAL

The main problem of this study was to find which factors are responsible for determining happiness and relating them to the current situation of pandemic caused by COVID-19. The objective was to analyze, through bibliographical research and application of a questionnaire (online), which factors are related (directly or indirectly) with the individuals' happiness. In view of the discussion of the variables addressed, it was possible to obtain results on the following factors: income does not have a positive relationship with happiness, just as unemployment is not linked to unhappiness. Respondents who declared themselves unhappy did not consider themselves healthy either, unlike happy and very happy. Finally, there was no distinction in happiness between single and childless individuals, again contrary to the pertinent literature.O presente trabalho teve como problemática central encontrar quais são os fatores responsáveis para se determinar a felicidade e relacioná-los com a atual situação de pandemia provocada pela COVID-19. Para tanto, utilizou-se de aplicação de questionário (online), pautado nas premissas da Economia Comportamental no que se refere à biocaracterísticas, bem como os fatores que se relacionam (direta ou indiretamente) com a felicidade dos indivíduos. Diante da discussão das variáveis abordadas foi possível obter resultados sobre os seguintes fatores: a renda não possui relação positiva com a felicidade, assim como o desemprego não está atrelado à infelicidade. Os respondentes que se declararam infelizes, também não se consideram saudáveis, diferentemente dos felizes e muito felizes. Por fim, não houve distinção na felicidade entre os indivíduos solteiros e sem filhos, mais uma vez contrariando a literatura pertinente

Characterization of Detergent-Insoluble Proteins in ALS Indicates a Causal Link between Nitrative Stress and Aggregation in Pathogenesis

BACKGROUND:Amyotrophic lateral sclerosis (ALS) is a progressive and fatal motor neuron disease, and protein aggregation has been proposed as a possible pathogenetic mechanism. However, the aggregate protein constituents are poorly characterized so knowledge on the role of aggregation in pathogenesis is limited. METHODOLOGY/PRINCIPAL FINDINGS:We carried out a proteomic analysis of the protein composition of the insoluble fraction, as a model of protein aggregates, from familial ALS (fALS) mouse model at different disease stages. We identified several proteins enriched in the detergent-insoluble fraction already at a preclinical stage, including intermediate filaments, chaperones and mitochondrial proteins. Aconitase, HSC70 and cyclophilin A were also significantly enriched in the insoluble fraction of spinal cords of ALS patients. Moreover, we found that the majority of proteins in mice and HSP90 in patients were tyrosine-nitrated. We therefore investigated the role of nitrative stress in aggregate formation in fALS-like murine motor neuron-neuroblastoma (NSC-34) cell lines. By inhibiting nitric oxide synthesis the amount of insoluble proteins, particularly aconitase, HSC70, cyclophilin A and SOD1 can be substantially reduced. CONCLUSION/SIGNIFICANCE:Analysis of the insoluble fractions from cellular/mouse models and human tissues revealed novel aggregation-prone proteins and suggests that nitrative stress contribute to protein aggregate formation in ALS

Human cortical organoids expose a differential function of GSK3 on cortical neurogenesis

The regulation of the proliferation and polarity of neural progenitors is crucial for the development of the brain cortex. Animal studies have implicated glycogen synthase kinase 3 (GSK3) as a pivotal regulator of both proliferation and polarity, yet the functional relevance of its signaling for the unique features of human corticogenesis remains to be elucidated. We harnessed human cortical brain organoids to probe the longitudinal impact of GSK3 inhibition through multiple developmental stages. Chronic GSK3 inhibition increased the proliferation of neural progenitors and caused massive derangement of cortical tissue architecture. Single-cell transcriptome profiling revealed a direct impact on early neurogenesis and uncovered a selective role of GSK3 in the regulation of glutamatergic lineages and outer radial glia output. Our dissection of the GSK3-dependent transcriptional network in human corticogenesis underscores the robustness of the programs determining neuronal identity independent of tissue architecture

Clinical Study Cirrhosis and Rapid Virological Response to Peginterferon Plus Ribavirin Determine Treatment Outcome in HCV-1 IL28B rs12979860 CC Patients

Background. The rs12979860 CC genotype of the interleukin 28B (IL28B) polymorphism is associated with high rates of sustained virological response (SVR) to peginterferon (PegIFN) and ribavirin (Rbv) in hepatitis C virus genotype-1 (HCV-1) patients. The impact of baseline predictors of treatment outcome and their interplay with viral kinetics in HCV-1 CC patients has not been fully evaluated. Aim. To identify baseline and on-therapy predictors of treatment failure in HCV-1 IL28B CC patients. Methods. Treatment-naïve HCV-1 patients, compliant to PegIFN and Rbv who did not discontinue treatment for nonvirological reasons, were analyzed. Results. 109 HCV-1 IL28B CC were studied. Sixty were males, 39 with BMI >25, 69 with >600,000 IU/mL HCV RNA, 15 with HCV1a, and 30 with cirrhosis. Overall, 75 (69%) achieved an SVR; cirrhosis was the only baseline predictor of treatment failure (OR: 2.58, 95% CI: 1.07-6.21) as SVR rates were 53% in cirrhotics versus 75% in noncirrhotics ( = 0.03). HCV RNA undetectability (<50 IU/mL) at week 4 (RVR) was achieved by 58 patients (53%). The SVR rates were independent of RVR in noncirrhotics, 76% (34/45) RVR (+) and 74% (25/34) RVR (−) ( = 0.9). In cirrhotic patients, SVR rates were significantly higher in RVR (+) compared to RVR (−) (10/13 (77%) versus 6/17 (35%) = 0.03). Conclusions. In HCV-1 IL28B CC patients, cirrhosis is the only clinical baseline predictor of PegIFN and Rbv treatment failure. However, in IL28B CC cirrhotics, the achievement of RVR identifies those patients who still have high rates of SVR to Peg-IFN/Rbv therapy

Influência do imaginário social em um período pandêmico, Uruguai, 2020

Study results that refer to the still current health emergency due to Covid-19 in Uruguay, a SouthAmerican country located between Argentina and Brazil. In terms of territory and population,it is the smallest country in the region, which has historically approached European standards,a trend that was selectively maintained in the context of the pandemic.Research strategy: an ethnographic study was scheduled in a limited time, between Apriland June, as soon as the health crisis began. Ten observation “antennas” were distributed, ineveryday life situations, in health institutions and others.The bibliographic resources used respond to a search for disciplinary bases with recognizedsolvency, rescuing authors and theoretical frameworks, integrating new theoretical-methodological proposals and antecedents related to this research. Motivation of the anthropological expertise: highlighting (cultural) differences in behavior during the health crisis, raising the interest in knowing about the objectification of socio-culturalfactors that influenced the containment of epidemiological progress and then, in the significantpresence of contagions within the health personnel.Results: we found models that order the understanding of social facts, of real data. Theapproach carried out contributes knowledge about representations, contents of social imaginary, which determine attitudes and affect objective conditions in the social, institutional andpersonal sphere.Resultados de estudio que refiere a la aún vigente emergencia sanitaria por Covid-19 en Uruguay, país de América del Sur ubicado entre Argentina y Brasil. En territorio y en población es el país más chico de la región, que históricamente se ha acercado a estándares europeos, tendencia que se mantuvo de forma selectiva en el contexto de pandemia. Estrategia de investigación: estudio de tipo etnográfico se programó en tiempo acotado, entre abril y junio, apenas iniciada la crisis sanitaria. Se distribuyeron diez “antenas” de observación, en situaciones de vida cotidiana, en instituciones de salud y otros.Los recursos bibliográficos utilizados responden a una búsqueda de bases disciplinarias con reconocida solvencia, rescatando autores y marcos teóricos, integrando nuevas propuestas teórico-metodológicas y antecedentes afines a esta investigación. Motivación del peritaje antropológico: destacar diferencias (culturales) de comportamientos durante la crisis sanitaria, plantear el interés de conocer sobre objetivación de factores socio culturales que incidieron en la contención del avance epidemiológico y luego, en significativa presencia de contagios dentro del propio personal de salud.Resultados: encontramos modelos que ordenan la comprensión de hechos sociales, de datos reales. El abordaje realizado aporta conocimiento sobre representaciones, contenidos de imaginario social, que determinan actitudes y afectan condiciones objetivas en el ámbito social, institucional y personal.Resultados do estudo que se referem à ainda atual emergência de saúde devido à Covid-19 noUruguai, país sul-americano localizado entre a Argentina e o Brasil. Em termos de território epopulação, é o menor país da região, que historicamente se aproximou dos padrões europeus,tendência que se manteve seletivamente no contexto de uma pandemia.Estratégia de pesquisa: um estudo etnográfico foi agendado em tempo limitado, entre abrile junho, assim que começou a crise de saúde. Foram distribuídas dez “antenas” de observação,em situações da vida cotidiana, em instituições de saúde e outras

Modulating eIF6 levels unveils the role of translation in ecdysone biosynthesis during Drosophila development

During development, ribosome biogenesis and translation reach peak activities, due to impetuous cell proliferation. Current models predict that protein synthesis elevation is controlled by transcription factors and signalling pathways. Developmental models addressing translation factors overexpression effects are lacking. Eukaryotic Initiation Factor 6 (eIF6) is necessary for ribosome biogenesis and efficient translation. eIF6 is a single gene, conserved from yeasts to mammals, suggesting a tight regulation need. We generated a Drosophila melanogaster model of eIF6 upregulation, leading to a boost in general translation and the shut-down of the ecdysone biosynthetic pathway. Indeed, translation modulation in S2 cells showed that translational rate and ecdysone biosynthesis are inversely correlated. In vivo, eIF6-driven alterations delayed Programmed Cell Death (PCD), resulting in aberrant phenotypes, partially rescued by ecdysone administration. Our data show that eIF6 triggers a translation program with far-reaching effects on metabolism and development, stressing the driving and central role of translation

The association of IL28B genotype with the histological features of chronic hepatitis C is HCV genotype dependent

The interleukin 28B (IL28B) rs12979860 polymorphism is associated with treatment outcome in hepatitis C virus (HCV) genotype 1 and 4 patients. Its association with the histological features of chronic hepatitis C and disease severity needs further clarifications. To assess the correlation between IL28B genotype, HCV genotype and liver biopsy findings in untreated patients. Materials and Methods: Pre-treatment liver biopsies from 335 HCV Caucasian patients (59% males, age 50 years) enrolled in the MIST study were staged for fibrosis and inflammation according to the METAVIR and the Ishak scoring systems; steatosis was dichotomized as = 5%. IL28B was typed by Taqman Single Nucleotide Polymorphism (SNP) genotyping assay. HCV genotype was 1 in 151 (45%), 2 in 99 (30%), 3 in 50 (15%) and 4 in 35 (10%) patients. IL28B genotype was CC in 117 (34%), CT in 166 (49%) and TT in 52 (15%). At univariate analysis, the IL28B CC genotype was associated with severe portal inflammation in HCV-1 patients (CC vs. CT/TT: 86% vs. 63%, p = 0.005), severe lobular inflammation in HCV-2 patients (CC vs. CT/TT: 44% vs. 23%, p = 0.03), and less fatty infiltration in HCV-1 patients (CC vs. CT/TT: 72% vs. 51%, p = 0.02). Despite the lack of any association between IL28B and fibrosis stage, in HCV-3 patients IL28B CC correlated with METAVIR F3-F4 (CC vs. CT/TT: 74% vs. 26%, p = 0.05). At multivariate analysis, the genotype CC remained associated with severe portal inflammation in HCV-1, only (Odds Ratio (OR): 95% Confidence Interval (CI): 3.24 (1.23-8.51)). IL28B genotype is associated with the histological features of chronic hepatitis C in a HCV genotype dependent manner, with CC genotype being independently associated with severe portal inflammation

Interaction between PNPLA3 I148M variant and age at infection in determining fibrosis progression in chronic hepatitis C

BACKGROUND AND AIMS: The PNPLA3 I148M sequence variant favors hepatic lipid accumulation and confers susceptibility to hepatic fibrosis and hepatocellular carcinoma. The aim of this study was to estimate the effect size of homozygosity for the PNPLA3 I148M variant (148M/M) on the fibrosis progression rate (FPR) and the interaction with age at infection in chronic hepatitis C (CHC). METHODS: FPR was estimated in a prospective cohort of 247 CHC patients without alcohol intake and diabetes, with careful estimation of age at infection and determination of fibrosis stage by Ishak score. RESULTS: Older age at infection was the strongest determinant of FPR (p<0.0001). PNPLA3 148M/M was associated with faster FPR in individuals infected at older age (above the median, 21 years; -0.64\ub10.2, n\u200a=\u200a8 vs. -0.95\ub10.3, n\u200a=\u200a166 log10 FPR respectively; p\u200a=\u200a0.001; confirmed for lower age thresholds, p<0.05), but not in those infected at younger age (p\u200a=\u200ans). The negative impact of PNPLA3 148M/M on fibrosis progression was more marked in subjects at risk of altered hepatic lipid metabolism (those with grade 2-3 steatosis, genotype 3, and overweight; p<0.05). At multivariate analysis, PNPLA3 148M/M was associated with FPR (incremental effect 0.08\ub10.03 log10 fibrosis unit per year; p\u200a=\u200a0.022), independently of several confounders, and there was a significant interaction between 148M/M and older age at infection (p\u200a=\u200a0.025). The association between 148M/M and FPR remained significant even after adjustment for steatosis severity (p\u200a=\u200a0.032). CONCLUSIONS: We observed an interaction between homozygosity for the PNPLA3 I148M variant and age at infection in determining fibrosis progression in CHC patients