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1.
Philos Trans A Math Phys Eng Sci ; 380(2215): 20200443, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34865527

RESUMO

The effect of the 2018 extreme meteorological conditions in Europe on methane (CH4) emissions is examined using estimates from four atmospheric inversions calculated for the period 2005-2018. For most of Europe, we find no anomaly in 2018 compared to the 2005-2018 mean. However, we find a positive anomaly for the Netherlands in April, which coincided with positive temperature and soil moisture anomalies suggesting an increase in biogenic sources. We also find a negative anomaly for the Netherlands for September-October, which coincided with a negative anomaly in soil moisture, suggesting a decrease in soil sources. In addition, we find a positive anomaly for Serbia in spring, summer and autumn, which coincided with increases in temperature and soil moisture, again suggestive of changes in biogenic sources, and the annual emission for 2018 was 33 ± 38% higher than the 2005-2017 mean. These results indicate that CH4 emissions from areas where the natural source is thought to be relatively small can still vary due to meteorological conditions. At the European scale though, the degree of variability over 2005-2018 was small, and there was negligible impact on the annual CH4 emissions in 2018 despite the extreme meteorological conditions. This article is part of a discussion meeting issue 'Rising methane: is warming feeding warming? (part 2)'.


Assuntos
Metano , Europa (Continente) , Metano/análise , Estações do Ano
2.
Hum Reprod ; 36(11): 2975-2991, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-34480478

RESUMO

STUDY QUESTION: Can a targeted whole exome sequencing (WES) on a cohort of women showing a primary ovarian insufficiency (POI) phenotype at a young age, combined with a study of copy number variations, identify variants in candidate genes confirming their deleterious effect on ovarian function? SUMMARY ANSWER: This integrated approach has proved effective in identifying novel candidate genes unveiling mechanisms involved in POI pathogenesis. WHAT IS KNOWN ALREADY: POI, a condition occurring in 1% of women under 40 years of age, affects women's fertility leading to a premature loss of ovarian reserve. The genetic causes of POI are highly heterogeneous and several determinants contributing to its prominent oligogenic inheritance pattern still need to be elucidated. STUDY DESIGN, SIZE, DURATION: WES screening for pathogenic variants of 41 Italian women with non-syndromic primary and early secondary amenorrhoea occurring before age 25 was replicated on another 60 POI patients, including 35 French and 25 American women, to reveal statistically significant shared variants. PARTICIPANTS/MATERIALS, SETTING, METHODS: The Italian POI patients' DNA were processed by targeted WES including 542 RefSeq genes expressed or functioning during distinct reproductive or ovarian processes (e.g. DNA repair, meiosis, oocyte maturation, folliculogenesis and menopause). Extremely rare variants were filtered and selected by means of a Fisher Exact test using several publicly available datasets. A case-control Burden test was applied to highlight the most significant genes using two ad-hoc control female cohorts. To support the obtained data, the identified genes were screened on a novel cohort of 60 Caucasian POI patients and the same case-control analysis was carried out. Comparative analysis of the human identified genes was performed on mouse and Drosophila melanogaster by analysing the orthologous genes in their ovarian phenotype, and two of the selected genes were fruit fly modelled to explore their role in fertility. MAIN RESULTS AND THE ROLE OF CHANCE: The filtering steps applied to search for extremely rare pathogenic variants in the Italian cohort revealed 64 validated single-nucleotide variants/Indels in 59 genes in 30 out of 41 screened women. Burden test analysis highlighted 13 ovarian genes as being the most enriched and significant. To validate these findings, filtering steps and Burden analysis on the second cohort of Caucasian patients yielded 11 significantly enriched genes. Among them, AFP, DMRT3, MOV10, FYN and MYC were significant in both patient cohorts and hence were considered strong candidates for POI. Mouse and Drosophila comparative analysis evaluated a conserved role through the evolution of several candidates, and functional studies using a Drosophila model, when applicable, supported the conserved role of the MOV10 armitage and DMRT3 dmrt93B orthologues in female fertility. LARGE SCALE DATA: The datasets for the Italian cohort generated during the current study are publicly available at ClinVar database (http://www.ncbi.nlm.nih.gov/clinvar/): accession numbers SCV001364312 to SCV001364375. LIMITATIONS, REASONS FOR CAUTION: This is a targeted WES analysis hunting variants in candidate genes previously identified by different genomic approaches. For most of the investigated sporadic cases, we could not track the parental inheritance, due to unavailability of the parents' DNA samples; in addition, we might have overlooked additional rare variants in novel candidate POI genes extracted from the exome data. On the contrary, we might have considered some inherited variants whose clinical significance is uncertain and might not be causative for the patients' phenotype. Additionally, as regards the Drosophila model, it will be extremely important in the future to have more mutants or RNAi strains available for each candidate gene in order to validate their role in POI pathogenesis. WIDER IMPLICATIONS OF THE FINDINGS: The genomic, statistical, comparative and functional approaches integrated in our study convincingly support the extremely heterogeneous oligogenic nature of POI, and confirm the maintenance across the evolution of some key genes safeguarding fertility and successful reproduction. Two principal classes of genes were identified: (i) genes primarily involved in meiosis, namely in synaptonemal complex formation, asymmetric division and oocyte maturation and (ii) genes safeguarding cell maintenance (piRNA and DNA repair pathways). STUDY FUNDING/COMPETING INTEREST(S): This work was supported by Italian Ministry of Health grants 'Ricerca Corrente' (08C621_2016 and 08C924_2019) provided to IRCCS Istituto Auxologico Italiano, and by 'Piano Sostegno alla Ricerca' (PSR2020_FINELLI_LINEA_B) provided by the University of Milan; M.P.B. was supported by Telethon-Italy (grant number GG14181). There are no conflicts of interest.


Assuntos
Insuficiência Ovariana Primária , Animais , Variações do Número de Cópias de DNA , Drosophila , Drosophila melanogaster , Feminino , Humanos , Camundongos , Insuficiência Ovariana Primária/genética , RNA Helicases , Fatores de Transcrição/genética , Sequenciamento do Exoma
3.
Global Biogeochem Cycles ; 35(6): e2021GB007000, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34219915

RESUMO

We study the drivers behind the global atmospheric methane (CH4) increase observed after 2006. Candidate emission and sink scenarios are constructed based on proposed hypotheses in the literature. These scenarios are simulated in the TM5 tracer transport model for 1984-2016 to produce three-dimensional fields of CH4 and δ 13C-CH4, which are compared with observations to test the competing hypotheses in the literature in one common model framework. We find that the fossil fuel (FF) CH4 emission trend from the Emissions Database for Global Atmospheric Research 4.3.2 inventory does not agree with observed δ 13C-CH4. Increased FF CH4 emissions are unlikely to be the dominant driver for the post-2006 global CH4 increase despite the possibility for a small FF emission increase. We also find that a significant decrease in the abundance of hydroxyl radicals (OH) cannot explain the post-2006 global CH4 increase since it does not track the observed decrease in global mean δ 13C-CH4. Different CH4 sinks have different fractionation factors for δ 13C-CH4, thus we can investigate the uncertainty introduced by the reaction of CH4 with tropospheric chlorine (Cl), a CH4 sink whose abundance, spatial distribution, and temporal changes remain uncertain. Our results show that including or excluding tropospheric Cl as a 13 Tg/year CH4 sink in our model changes the magnitude of estimated fossil emissions by ∼20%. We also found that by using different wetland emissions based on a static versus a dynamic wetland area map, the partitioning between FF and microbial sources differs by 20 Tg/year, ∼12% of estimated fossil emissions.

4.
Hum Reprod ; 34(3): 574-583, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30689869

RESUMO

STUDY QUESTION: Can high resolution array-CGH analysis on a cohort of women showing a primary ovarian insufficiency (POI) phenotype in young age identify copy number variants (CNVs) with a deleterious effect on ovarian function? SUMMARY ANSWER: This approach has proved effective to clarify the role of CNVs in POI pathogenesis and to better unveil both novel candidate genes and pathogenic mechanisms. WHAT IS KNOWN ALREADY: POI describes the progression toward the cessation of ovarian function before the age of 40 years. Genetic causes are highly heterogeneous and despite several genes being associated with ovarian failure, most of genetic basis of POI still needs to be elucidated. STUDY DESIGN, SIZE, DURATION: The current study included 67 46,XX patients with early onset POI (<19 years) and 134 control females recruited between 2012 and 2016 at the Medical Cytogenetics and Molecular Genetics Lab, IRCCS Istituto Auxologico Italiano. PARTICIPANTS/MATERIALS, SETTING, METHODS: High resolution array-CGH analysis was carried out on POI patients' DNA. Results of patients and female controls were analyzed to search for rare CNVs. All variants were validated and subjected to a gene content analysis and disease gene prioritization based on the present literature to find out new ovary candidate genes. Case-control study with statistical analysis was carried out to validate our approach and evaluate any ovary CNVs/gene enrichment. Characterization of particular CNVs with molecular and functional studies was performed to assess their pathogenic involvement in POI. MAIN RESULTS AND THE ROLE OF CHANCE: We identified 37 ovary-related CNVs involving 44 genes with a role in ovary in 32 patients. All except one of the selected CNVs were not observed in the control group. Possible involvement of the CNVs in POI pathogenesis was further corroborated by a case-control analysis that showed a significant enrichment of ovary-related CNVs/genes in patients (P = 0.0132; P = 0.0126). Disease gene prioritization identified both previously reported POI genes (e.g. BMP15, DIAPH2, CPEB1, BNC1) and new candidates supported by transcript and functional studies, such as TP63 with a role in oocyte genomic integrity and VLDLR which is involved in steroidogenesis. LARGE SCALE DATA: ClinVar database (http://www.ncbi.nlm.nih.gov/clinvar/); accession numbers SCV000787656 to SCV000787743. LIMITATIONS, REASONS FOR CAUTION: This is a descriptive analysis for almost all of the CNVs identified. Inheritance studies of CNVs in some non-familial sporadic cases was not performed as the parents' DNA samples were not available. Addionally, RT-qPCR analyses were carried out in few cases as RNA samples were not always available and the genes were not expressed in blood. WIDER IMPLICATIONS OF THE FINDINGS: Our array-CGH screening turned out to be efficient in identifying different CNVs possibly implicated in disease onset, thus supporting the extremely wide genetic heterogeneity of POI. Since almost 50% of cases are negative rare ovary-related CNVs, array-CGH together with next generation sequencing might represent the most suitable approach to obtain a comprehensive genetic characterization of POI patients. STUDY FUNDING/COMPETING INTEREST(S): Supported by Italian Ministry of Health grants 'Ricerca Corrente' (08C203_2012) and 'Ricerca Finalizzata' (GR-2011-02351636, BIOEFFECT) to IRCCS Istituto Auxologico Italiano.


Assuntos
Hibridização Genômica Comparativa , Variações do Número de Cópias de DNA , Dosagem de Genes , Ovário/fisiologia , Insuficiência Ovariana Primária/genética , Adolescente , Idade de Início , Estudos de Casos e Controles , Criança , Bases de Dados Genéticas , Feminino , Genoma Humano , Humanos , Menopausa Precoce/genética , Mutação , Doenças Ovarianas/genética , Fenótipo , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética
5.
J Endocrinol Invest ; 41(8): 929-936, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29302920

RESUMO

PURPOSE: Few examples of the involvement of a single gene in idiopathic short stature have been described until now. Our aim was to identify the causative gene of proportionate short stature in a large family showing co-segregation of the phenotype with the reciprocal translocation t(10;15)(q22;q24). METHODS: FISH mapping was carried out with BACs and long-range PCR probes to identify the smallest genomic regions harboring the translocation breakpoints. Real-Time RT-PCR was performed in blood after pre-amplification of target genes cDNA. RESULT: The affected family members presented with a final height of between - 2.41 and - 4.18 SDS and very mild skeletal dysmorphisms. Growth rates of the proband and of her cousin, whose childhood and pre-pubertal bone age corresponded to the chronological age, showed a poor growth spurt during treatment with rhGH. However, their adult height was greater than that of their untreated mothers, suggesting efficacy of GH therapy. Breakpoint mapping revealed that the translocation t(10;15)(q22.3;q26.1) disrupts, on 15q, the ACAN gene at intron 1, decreasing its transcriptional expression. CONCLUSIONS: This is the first description of a chromosome rearrangement disrupting ACAN and leading to its haploinsufficiency. ACAN loss of function should be considered a potential underpinning of short patients who display a poor growth spurt and belong to families with autosomal dominant segregation of proportionate short stature. Besides this core phenotype, literature review suggests that advanced bone age, early onset osteochondritis dissecans, osteoarthritis, intervertebral disc disease as well as craniofacial dysmorphisms can be important suggestive phenotypes in affected families.


Assuntos
Cromossomos Humanos Par 10/genética , Cromossomos Humanos Par 15/genética , Nanismo/genética , Translocação Genética , Adolescente , Adulto , Agrecanas , Criança , Nanismo/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Prognóstico , Adulto Jovem
6.
J Environ Manage ; 183(Pt 3): 959-971, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27681872

RESUMO

Emission data from EDGAR (Emissions Database for Global Atmospheric Research), rather than economic data, are used to estimate the effect of policies and of the global exports of policy-regulated goods, such as vehicles, on global emissions. The results clearly show that the adoption of emission standards for the road transport sector in the two main global markets (Europe and North America) has led to the global proliferation of emission-regulated vehicles through exports, regardless the domestic regulation in the country of destination. It is in fact more economically convenient for vehicle manufacturers to produce and sell a standard product to the widest possible market and in the greatest possible amounts. The EU effect (European Union effect) is introduced as a global counterpart to the California effect. The former is a direct consequence of the penetration of the EURO standards in the global markets by European and Japanese manufacturers, which effectively export the standard worldwide. We analyze the effect on PM2.5 emissions by comparing a scenario of non-EURO standards against the current estimates provided by EDGAR. We find that PM2.5 emissions were reduced by more than 60% since the 1990s worldwide. Similar investigations on other pollutants confirm the hypothesis that the combined effect of technological regulations and their diffusion through global markets can also produce a positive effect on the global environment. While we acknowledge the positive feedback, we also demonstrate that current efforts and standards will be totally insufficient should the passenger car fleets in emerging markets reach Western per capita figures. If emerging countries reach the per capita vehicle number of the USA and Europe under current technological conditions, then the world will suffer pre-1990 emission levels.


Assuntos
União Europeia , Veículos Automotores/normas , Emissões de Veículos , Poluentes Atmosféricos , California , Política Ambiental , Europa (Continente) , Indústria Manufatureira/normas , Estados Unidos
7.
Environ Int ; 172: 107760, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36708630

RESUMO

The EU, seeking to be a global leader in the fight against climate change, is moving ahead with ambitious policies to mitigate greenhouse gases emissions. In this context, the Fit for 55 package (FF55) is a set of proposals to revise and update EU legislation, to ensure that policies are in line with the climate goals of cutting emissions by at least 55% by 2030. Whilst these policies are designed for climate purposes, they will have positive side-effects (co-benefits) on air quality. Separately, additional policies are also in place to reduce emissions of related air pollutants and to improve air quality concentrations on EU territory. In this work, through a modelling study, we analyse the benefits of these policies via the health benefits arising from the resulting reductions in yearly average PM2.5 concentrations. Results are analysed by assessing and comparing morbidity and mortality impacts as computed using both the HRAPIE (Health risks of air pollution in Europe, WHO, as implemented in the CaRBonH model) and the GBD (Global Burden of Disease, as implemented in FASST-GBD model) approaches. Even when considering the uncertainty and variability in the results obtained using the two approaches, it is clear that EU policies can bring health and economic benefit in EU, with several Billions of Euro of benefits both in terms of morbidity and mortality indicators.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Gases de Efeito Estufa , Material Particulado/análise , Poluição do Ar/análise , Poluentes Atmosféricos/análise , Gases de Efeito Estufa/análise , Mudança Climática , Políticas
8.
G Ital Med Lav Ergon ; 34(3 Suppl): 252-6, 2012.
Artigo em Italiano | MEDLINE | ID: mdl-23405634

RESUMO

The aim of this review is pointing out the most relevant allergic and chemical risk factors in health care settings. Some tables summarize the main sensitizing agents, the most frequent allergic diseases and examples of alternative gloves and materials currently available. Some suggestions, to evaluate the allergic risk related to specific tasks in the different hospital departments, are given in order to underline possible failures and to plan focused preventive actions. The chemical hazard has been valued on the basis of the current exposure, which is significantly improved due to structural and technological changes adopted in almost all hospitals. However there are still some critical points due to the use of particularly toxic substances and new molecules, whose health effects should be carefully evaluated, and to a more extensive use of techniques and procedures previously limited to a few work realities.


Assuntos
Substâncias Perigosas/efeitos adversos , Hospitais/normas , Hipersensibilidade/etiologia , Saúde Ocupacional/normas , Gestão de Riscos , Humanos
9.
Nat Food ; 3(11): 942-956, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-37118218

RESUMO

Food systems are important contributors to global emissions of air pollutants. Here, building on the EDGAR-FOOD database of greenhouse gas emissions, we estimate major air pollutant compounds emitted by different stages of the food system, at country level, during the past 50 years, resulting from food production, processing, packaging, transport, retail, consumption and disposal. Air pollutant estimates from food systems include total nitrogen and its components (N2O, NH3 and NOx), SO2, CO, non-methane volatile organic compounds (NMVOC) and particulate matter (PM10, PM2.5, black carbon and organic carbon). We show that 10% to 90% of air pollutant emissions come from food systems, resulting from steady increases over the past five decades. In 2018, more than half of total N (and 87% of ammonia) emissions come from food systems and up to 35% of particulate matter. Food system emissions are responsible for about 22.4% of global mortality due to poor air quality and 1.4% of global crop production losses.

10.
G Ital Med Lav Ergon ; 33(3 Suppl): 19-22, 2011.
Artigo em Italiano | MEDLINE | ID: mdl-23393791

RESUMO

The movement computerized analysis of upper limb is a valid support in the definition of residual functional capability and of specific work suitability in complex cases. This methodology of evaluation is able to correctly and objectively define the tridimensional ranges of motion of every patient's upper limb. This fact can be particularly useful for workers coming back to work after a work-related or a not work-related accident of for handicapped workers at the beginning of a new work activity. We report a research carried out using computerized analysis of motion of upper limbs in 20 engineering workers.


Assuntos
Diagnóstico por Computador , Engenharia , Doenças Profissionais/diagnóstico , Extremidade Superior , Humanos , Medicina do Trabalho/métodos
11.
Nat Food ; 2(3): 198-209, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37117443

RESUMO

We have developed a new global food emissions database (EDGAR-FOOD) estimating greenhouse gas (GHG; CO2, CH4, N2O, fluorinated gases) emissions for the years 1990-2015, building on the Emissions Database of Global Atmospheric Research (EDGAR), complemented with land use/land-use change emissions from the FAOSTAT emissions database. EDGAR-FOOD provides a complete and consistent database in time and space of GHG emissions from the global food system, from production to consumption, including processing, transport and packaging. It responds to the lack of detailed data for many countries by providing sectoral contributions to food-system emissions that are essential for the design of effective mitigation actions. In 2015, food-system emissions amounted to 18 Gt CO2 equivalent per year globally, representing 34% of total GHG emissions. The largest contribution came from agriculture and land use/land-use change activities (71%), with the remaining were from supply chain activities: retail, transport, consumption, fuel production, waste management, industrial processes and packaging. Temporal trends and regional contributions of GHG emissions from the food system are also discussed.

12.
Sci Rep ; 8(1): 1482, 2018 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-29367716

RESUMO

The formation of new atmospheric particles involves an initial step forming stable clusters less than a nanometre in size (<~1 nm), followed by growth into quasi-stable aerosol particles a few nanometres (~1-10 nm) and larger (>~10 nm). Although at times, the same species can be responsible for both processes, it is thought that more generally each step comprises differing chemical contributors. Here, we present a novel analysis of measurements from a unique multi-station ground-based observing system which reveals new insights into continental-scale patterns associated with new particle formation. Statistical cluster analysis of this unique 2-year multi-station dataset comprising size distribution and chemical composition reveals that across Europe, there are different major seasonal trends depending on geographical location, concomitant with diversity in nucleating species while it seems that the growth phase is dominated by organic aerosol formation. The diversity and seasonality of these events requires an advanced observing system to elucidate the key processes and species driving particle formation, along with detecting continental scale changes in aerosol formation into the future.

13.
Cancer Res ; 50(7): 2022-6, 1990 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-2317791

RESUMO

The relation between cellular phenotype and expression of chromosomal high mobility group proteins 14 and 17 (HMG-14 and HMG-17) has been examined in human cell lineages. Quantitation of HMG-14 and HMG-17 mRNA in several human cell lines revealed differences in both the steady state mRNA level and in the ratio of HMG-14 to HMG-17 mRNA. Analysis of phenotypically distinct derivatives of human bronchial epithelial cells revealed small differences between both the steady state mRNA levels and the relative amount of these proteins among the clonal variants. The effect of myeloid differentiation on the mRNA level of HMG-14 and HMG-17 was examined in the human promyelocytic leukemia cell line HL-60 following treatment with several granulocytic and monocytic differentiating agents. The ratio of HMG-17 mRNA to either HMG-14 or histone H4 mRNA varied among the cell phenotypes suggesting that phenotype switching may result in detectable alterations in the expression of the HMG-14 and HMG-17 genes. The data suggest that, although the ratio of HMG-14 to HMG-17 mRNA varies among human cell lines, these variations are relatively small.


Assuntos
Proteínas de Grupo de Alta Mobilidade/genética , Northern Blotting , Brônquios/fisiologia , Diferenciação Celular , Transformação Celular Neoplásica , Epitélio/fisiologia , Expressão Gênica , Granulócitos/fisiologia , Histonas/genética , Humanos , Monócitos/fisiologia , RNA Mensageiro/genética , Células Tumorais Cultivadas/fisiologia
14.
Oncogene ; 18(18): 2836-45, 1999 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-10362254

RESUMO

We have analysed in vivo the -2.0 kb enhancer of the human urokinase-type plasminogen activator (uPA) gene in HepG2 cells, in which gene expression can be induced by phorbol esters. The results reveal that, within the regulatory region, the enhancer, the silencer and the minimal promoter become hypersensitive to deoxyribonuclease I (DNase I) upon induction of transcription. The hypersensitivity of the enhancer can be reversed after removal of the inducer. In vivo footprinting analysis indicates that all the cis-acting elements of the enhancer, previously identified in vitro, are occupied in vivo upon 12-O-tetradecanoyl-phorbol-13-acetate (TPA) stimulation of HepG2 cells. Micrococcal nuclease (MNase) cleavage of this region fails to reveal discrete nucleosomal boundaries in vivo in close proximity of the enhancer, either before or after stimulation. Furthermore, this region does not lose its nucleosomal configuration after TPA induction of transcription. An approximately 600 bp long region around the enhancer becomes more, but not fully, accessible to restriction endonucleases upon stimulation. A time-course experiment shows that this accessibility reaches a plateau after a 1 h TPA treatment suggesting the persistent presence of nucleosomes. These results indicate that TPA induces the binding of transcription factors to the uPA enhancer without chromatin remodelling of this region.


Assuntos
Carcinógenos/farmacologia , Elementos Facilitadores Genéticos , Acetato de Tetradecanoilforbol/farmacologia , Ativador de Plasminogênio Tipo Uroquinase/genética , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Sítios de Ligação , Cromatina/genética , Cromatina/ultraestrutura , Desoxirribonuclease I/genética , Desoxirribonuclease I/metabolismo , Humanos , Nuclease do Micrococo/metabolismo , NF-kappa B/metabolismo , Nucleossomos/genética , Nucleossomos/metabolismo , RNA Mensageiro/efeitos dos fármacos , Sequências Reguladoras de Ácido Nucleico , Mapeamento por Restrição , Fatores de Tempo , Fatores de Transcrição/metabolismo , Transcrição Gênica , Ativador de Plasminogênio Tipo Uroquinase/efeitos dos fármacos
15.
J Mol Biol ; 217(1): 75-84, 1991 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-1988681

RESUMO

The expression of the gene coding for chromosomal protein HMG-17 is down regulated during chicken erythrocyte maturation. The transcriptional down regulation is associated with major alterations in the chromatin structure of this gene. The 5' region of the gene contains both constitutive and developmental stage-specific deoxyribonuclease I (DNase I) hypersensitive sites. The constitutive sites bracket the "CpG island" present in the gene, which remains hypomethylated throughout the various developmental stages. During erythropoiesis, the gene acquires a distinct structure that, upon digestion with micrococcal nuclease (MNase) yields an unusual repeat. Two nucleosomes, with a 200 base-pair repeat, are positioned immediately downstream from the start of transcription. Immediately downstream and upstream from these nucleosomes, the boundaries between MNase sites change to a 75 base-pair repeat, which indicates an unusual chromatin structure. The differentiation related changes in the DNase I and MNase digestion pattern in the 5' region of the gene suggest that sequences present in the first intron may be involved in gene regulation. The results may be relevant to the regulation of the entire HMG-14/-17 gene family.


Assuntos
Cromatina/química , Eritropoese/genética , Regulação da Expressão Gênica , Proteínas de Grupo de Alta Mobilidade/genética , Animais , Composição de Bases , Northern Blotting , Southern Blotting , Diferenciação Celular/genética , Embrião de Galinha , Galinhas , Cromatina/metabolismo , Desoxirribonuclease I/metabolismo , Regulação para Baixo , Metilação , RNA Mensageiro/metabolismo , Mapeamento por Restrição , Transcrição Gênica
16.
J Mol Biol ; 228(2): 442-9, 1992 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-1453455

RESUMO

Chromosomal proteins HMG-14 and HMG-17 have a modular structure. Here we examine whether the putative nucleosome-binding domain in these proteins can function as an independent module. Mobility shift assays with recombinant HMG-17 indicate that synthetic molecules can be used to analyze the interaction of this protein with the nucleosome core. Peptides corresponding to various regions of the protein have been synthesized and their interaction with nucleosome cores analyzed by mobility shift, thermal denaturation and DNase I digestion. A 30 amino acid long peptide, corresponding to the putative nucleosome-binding domain of HMG-17, specifically shifts the mobility of cores as compared to free DNA, elevates the tm of both the premelt and main melt of the cores and protects from DNase I digestion the same nucleosomal DNA sites as the intact protein. The binding of both the peptide and the intact protein is lost upon digestion of the histone tails by trypsin. The nucleosomal binding sites of the peptide appear identical to those of the intact protein. Thus, a region of the protein can acts as an independent functional domain. This supports the notion that HMG-14 and HMG-17 are modular proteins. This finding is relevant to the understanding of the function and evolution of HMG-14/-17, the only nucleosome core particle binding proteins known to date.


Assuntos
Proteínas de Grupo de Alta Mobilidade/metabolismo , Nucleossomos/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Evolução Biológica , Desoxirribonuclease I , Humanos , Dados de Sequência Molecular , Peptídeos/síntese química , Peptídeos/metabolismo , Desnaturação Proteica , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Suínos , Termodinâmica
17.
J Mol Biol ; 236(1): 189-98, 1994 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-8107104

RESUMO

The position of chromosomal proteins HMG-14 and HMG-17 in nucleosome cores and in chromatosomes lacking linker histones has been mapped by hydroxyl radical footprinting. Both the nucleosome core and the H1/H5 depleted chromatosome can specifically bind two molecules of HMG-14/-17. The path of HMG-14 on the surface of chromatin subunits is indistinguishable from that of HMG-17. The bound HMGs protect the DNA from hydroxyl radical cleavage 25 base-pairs from the end of the DNA in nucleosome cores and in each of the two major grooves of the DNA flanking the nucleosomal dyad axis. Thus, in both cores and H1/H5-depleted chromatosomes the proteins bridge two adjacent DNA strands on the surface of the particles. The sites occupied by HMG near the end of the chromatosome-length particles are distinct from those occupied by the H1/H5 linker histones. In the region of the dyad axis the binding sites of HMGs overlap those of the linker histones. The placement of HMG-14/-17 near the nucleosomal dyad axis raises the possibility that interactions between histone H1 and HMGs may affect the transcriptional potential of chromatin.


Assuntos
Cromatina/metabolismo , Proteínas de Grupo de Alta Mobilidade/química , Sequência de Aminoácidos , Animais , Sítios de Ligação , Galinhas , Cromatina/ultraestrutura , DNA/química , DNA/metabolismo , Eritrócitos/metabolismo , Proteínas de Grupo de Alta Mobilidade/metabolismo , Humanos , Radical Hidroxila , Modelos Estruturais , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Nucleossomos/metabolismo , Nucleossomos/ultraestrutura , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos
18.
FEBS Lett ; 381(1-2): 1-6, 1996 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-8641412

RESUMO

The main ligand-binding determinant of the human urokinase receptor (uPAR) is located in the amino terminal domain D1, but when isolated this domain presents a 1500 fold lower affinity than the intact three-domain uPAR (D1D2D3). uPAR mutants missing either domain 2 (D1HD3) or domain 3 (D1D2) were expressed in murine LB6 cells and showed to be properly GPI-anchored to the cell surface. Binding assays with [125I]ATF demonstrated that these mutants possessed a normal (D1D2) or slightly reduced (D1HD3) affinity, indicating that a high ligand-affinity may be achieved by a combination of D1 with domain D2 or D3.


Assuntos
Receptores de Superfície Celular/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação , Células Clonais , Imunofluorescência , Glicosilfosfatidilinositóis/metabolismo , Humanos , Cinética , Células L , Ligantes , Camundongos , Dados de Sequência Molecular , Mutagênese , Mutagênese Insercional , Fosfatidilinositol Diacilglicerol-Liase , Diester Fosfórico Hidrolases/biossíntese , Diester Fosfórico Hidrolases/metabolismo , Diester Fosfórico Hidrolases/farmacologia , Receptores de Superfície Celular/biossíntese , Receptores de Superfície Celular/isolamento & purificação , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Transfecção , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
19.
Thromb Haemost ; 81(5): 767-74, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10365752

RESUMO

We have previously shown that urokinase-type plasminogen activator (uPA) is highly expressed in murine C2C12 myoblasts and that antibodies against uPA are able to block both myoblast fusion and differentiation. Here we show the characterization of cis-acting elements in the mouse uPA promoter in vitro which are involved in uPA gene expression in C2C 12 myoblast cells. DNase I hypersensitive (HS) site analysis revealed the presence of three HS sites in myoblasts. Deletion analysis of stably transfected uPA-promoter constructs revealed that at least two of the three HS sites accounted for the high transcriptional expression in C2C12 cells. One was located at -2.4 kb and corresponded to a known PEA3/AP1A element and the other one was located at -4.9 kb and contained a CArG box and a CRE element. So far, no regulatory function had been assigned to this CRE/CArG element. Both HS sites alone were able to activate transcription of a heterologous promoter and showed a cooperative effect when placed together. Electrophoretic mobility-shift assays using myoblast nuclear extracts and specific antibodies demonstrated that cJun, JunD and ATF2 bound to the PEA3/AP1A element, whereas the CRE/CArG element bound SRF. Altogether, these results suggest that high uPA expression in myoblasts is dependent on the cooperation of two regulatory sites in the uPA promoter.


Assuntos
Músculo Esquelético/metabolismo , Ativação Transcricional , Ativador de Plasminogênio Tipo Uroquinase/genética , Animais , Regulação Enzimológica da Expressão Gênica , Camundongos , Sondas de Oligonucleotídeos , Regiões Promotoras Genéticas
20.
J Thorac Cardiovasc Surg ; 101(6): 1088-92, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2038203

RESUMO

From November 1973 to January 1988, 15 patients with cor triatriatum underwent surgical correction at the Department of Cardiac Surgery, Ospedali Riuniti, Bergamo, Italy. Their ages ranged from 15 days to 48 years. Eight patients (53%) were younger than age 1 year. Evidence of congestive heart failure was present in five infants, whereas three infants, three children, and two adults initially had signs of pulmonary venous obstruction, and two children had a heart murmur only. Five patients had cor triatriatum alone; in ten cases there also was an atrial septal defect. Associated anomalies in four patients included left superior vena cava, ventricular septal defect and left superior vena cava, partial anomalous pulmonary venous connection, and bilateral partial anomalous pulmonary venous connection. Cor triatriatum was repaired with the aid of cardiopulmonary bypass in all patients. Excision of the membrane was accomplished with a right atrial approach in 13 patients and a left atriotomy in one patient. Both atria were opened in one case. All associated anomalies were simultaneously corrected. Three patients (20%) died early after operation. Among the 12 survivors, no late events have occurred, and all of them are presently in New York Heart Association functional class I. A recent echocardiogram shows absence of residual obstruction or shunt and good development of the left cardiac chambers.


Assuntos
Coração Triatriado/cirurgia , Adolescente , Criança , Pré-Escolar , Coração Triatriado/complicações , Coração Triatriado/diagnóstico , Coração Triatriado/patologia , Feminino , Insuficiência Cardíaca/etiologia , Humanos , Lactente , Recém-Nascido , Masculino , Métodos , Pessoa de Meia-Idade
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