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1.
Appl Environ Microbiol ; 90(3): e0179123, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-38334306

RESUMO

Control measures are being introduced globally to reduce the prevalence of antibiotic resistance (ABR) in bacteria on farms. However, little is known about the current prevalence and molecular ecology of ABR in bacterial species with the potential to be key opportunistic human pathogens, such as Escherichia coli, on South American farms. Working with 30 dairy cattle farms and 40 pig farms across two provinces in central-eastern Argentina, we report a comprehensive genomic analysis of third-generation cephalosporin-resistant (3GC-R) E. coli, which were recovered from 34.8% (cattle) and 47.8% (pigs) of samples from fecally contaminated sites. Phylogenetic analysis revealed substantial diversity suggestive of long-term horizontal and vertical transmission of 3GC-R mechanisms. CTX-M-15 and CTX-M-2 were more often produced by isolates from dairy farms, while CTX-M-8 and CMY-2 and co-carriage of amoxicillin/clavulanate resistance and florfenicol resistance were more common in isolates from pig farms. This suggests different selective pressures for antibiotic use in these two animal types. We identified the ß-lactamase gene blaROB, which has previously only been reported in the family Pasteurellaceae, in 3GC-R E. coli. blaROB was found alongside a novel florfenicol resistance gene, ydhC, also mobilized from a pig pathogen as part of a new composite transposon. As the first comprehensive genomic survey of 3GC-R E. coli in Argentina, these data set a baseline from which to measure the effects of interventions aimed at reducing on-farm ABR and provide an opportunity to investigate the zoonotic transmission of resistant bacteria in this region. IMPORTANCE: Little is known about the ecology of critically important antibiotic resistance among bacteria with the potential to be opportunistic human pathogens (e.g., Escherichia coli) on South American farms. By studying 70 pig and dairy cattle farms in central-eastern Argentina, we identified that third-generation cephalosporin resistance (3GC-R) in E. coli was mediated by mechanisms seen more often in certain species and that 3GC-R pig E. coli were more likely to be co-resistant to florfenicol and amoxicillin/clavulanate. This suggests that on-farm antibiotic usage is key to selecting the types of E. coli present on these farms. 3GC-R E. coli and 3GC-R plasmids were diverse, suggestive of long-term circulation in this region. We identified the de novo mobilization of the resistance gene blaROB from pig pathogens into E. coli on a novel mobile genetic element, which shows the importance of surveying poorly studied regions for antibiotic resistance that might impact human health.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Tianfenicol/análogos & derivados , Animais , Humanos , Suínos , Bovinos , Escherichia coli/metabolismo , Fazendas , Cefalosporinas/farmacologia , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/veterinária , Infecções por Escherichia coli/microbiologia , Filogenia , Antibacterianos/farmacologia , Antibacterianos/metabolismo , beta-Lactamases/genética , beta-Lactamases/metabolismo , Genômica , Amoxicilina , Ácido Clavulânico
2.
J Cross Cult Gerontol ; 39(2): 189-205, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38717711

RESUMO

The phenomenon of world aging is not foreign to indigenous communities. In the last few years, research about these communities around the world has increased, but aging in indigenous towns still has not been studied widely. The purpose of this research is to interpret the meaning of old age in two indigenous communities from the Colombian Andean-Amazon region (the Inga and Kamëntsa) to reinforce the relevance of the local sociocultural context within the configuration of the meaning of old age and to emphasize the importance of considering particular regional characteristics for the design of policies and interventions aiming to recognize and integrate indigenous populations. This is a qualitative study with an interactionism-symbolism approach. In total, six indigenous people older than 60 years from two ancestral communities from the Colombian Andean-Amazon region participated in the in-depth interviews. Data analysis was carried out in three moments: discovery, coding, and relativization of the information. The results show that old age means wisdom, "I am wise," which is supported in the cosmology and the trajectory of life, reinforces the identity and autonomy, and allows them to be agents in the dynamics of their communities from the "I do," in other words, their roles as builders of the family-society and as guards of ancestral knowledge. The loss of this knowledge and the elements that it is composed of uproot them and put them at risk of disappearing as individuals and as a collective. In conclusion, the meaning of old age in these communities is not centered on a determinate age; you are not old, you are wise, and as such, they play a central role in their communities. Moreover, wisdom is built in parallel with their cosmology and assigns them the task of safekeeping ancestral knowledge. In order to do this, they use oral tradition as a tool, words that are born in their territories, travel in a nonlinear timeline, and get strengthened by the community while also protecting it and building it. Knowing what aging means for Indigenous communities can facilitate to the development of policies and initiatives and to provide culturally appropriate and effective programs.


Assuntos
Envelhecimento , Indígenas Sul-Americanos , Povos Indígenas , Pesquisa Qualitativa , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Envelhecimento/etnologia , Colômbia/etnologia , Entrevistas como Assunto
3.
Can J Neurol Sci ; 50(4): 612-617, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-35831924

RESUMO

OBJECTIVES: We aimed to explore the prevalence of peroneal neuropathy in children during coronavirus disease-19 (COVID-19) pandemic. BACKGROUND: Since the COVID-19 outbreak, many children worldwide have experienced a dramatic lifestyle changes, including conducting most daily activities indoors. Peroneal nerve palsy is one of the most common entrapment neuropathies and circumstances as prolonged immobilization or leg crossing predisposes an individual to peroneal neuropathy. METHODS: This is a case-control retrospective study that included patients referred to our neurophysiology clinic with foot drop. We compared the prevalence of spontaneous peroneal neuropathy 1 year before (April 2019/March 2020) and 1 year during the COVID-19 pandemic (April 2020/March 2021); and we also continued collecting data prospectively between April and September 2021 analysis the whole pandemic period. RESULTS: Totally, 399 patient clinical notes and NCS/EMG reports were reviewed, 220 were evaluated 1 year before and 179 1 year during COVID-19 pandemic. During the COVID-19 pandemic, there was a higher prevalence of peroneal neuropathy (odds ratio 4.74, 95%CI 1.30-17.25, p = 0.0183). In the COVID group (n = 11), mean age was 14 years and 63.4% were males. Mean age was 15 years and 66.7% were males in the Control group (n = 3). There was a significant difference in the time from symptoms onset to the neurophysiology assessment, with a mean time of 14 days in the Control group and 87.5 days in the COVID group. CONCLUSIONS: This study provides evidence that during the COVID-19 pandemic period, there was a higher prevalence of peroneal neuropathy among children. Strategies to prevent peroneal neuropathy should be recommened to this age group.


Assuntos
COVID-19 , Neuropatias Fibulares , Masculino , Humanos , Criança , Adolescente , Feminino , Neuropatias Fibulares/epidemiologia , Neuropatias Fibulares/diagnóstico , Pandemias , Estudos Retrospectivos , Prevalência , COVID-19/epidemiologia
4.
Am J Hum Genet ; 104(3): 466-483, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30827497

RESUMO

Gene-panel and whole-exome analyses are now standard methodologies for mutation detection in Mendelian disease. However, the diagnostic yield achieved is at best 50%, leaving the genetic basis for disease unsolved in many individuals. New approaches are thus needed to narrow the diagnostic gap. Whole-genome sequencing is one potential strategy, but it currently has variant-interpretation challenges, particularly for non-coding changes. In this study we focus on transcriptome analysis, specifically total RNA sequencing (RNA-seq), by using monogenetic neuromuscular disorders as proof of principle. We examined a cohort of 25 exome and/or panel "negative" cases and provided genetic resolution in 36% (9/25). Causative mutations were identified in coding and non-coding exons, as well as in intronic regions, and the mutational pathomechanisms included transcriptional repression, exon skipping, and intron inclusion. We address a key barrier of transcriptome-based diagnostics: the need for source material with disease-representative expression patterns. We establish that blood-based RNA-seq is not adequate for neuromuscular diagnostics, whereas myotubes generated by transdifferentiation from an individual's fibroblasts accurately reflect the muscle transcriptome and faithfully reveal disease-causing mutations. Our work confirms that RNA-seq can greatly improve diagnostic yield in genetically unresolved cases of Mendelian disease, defines strengths and challenges of the technology, and demonstrates the suitability of cell models for RNA-based diagnostics. Our data set the stage for development of RNA-seq as a powerful clinical diagnostic tool that can be applied to the large population of individuals with undiagnosed, rare diseases and provide a framework for establishing minimally invasive strategies for doing so.


Assuntos
Marcadores Genéticos , Variação Genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Doenças Musculares/diagnóstico , Mutação , Doenças Raras/diagnóstico , Adolescente , Adulto , Células Cultivadas , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Doenças Musculares/genética , Doenças Raras/genética , Transcriptoma , Adulto Jovem
5.
Environ Microbiol ; 24(8): 3640-3654, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35315253

RESUMO

The factors shaping the composition of the tree mycobiome are still under investigation. We tested the effects of host genotype, site, host phenotypic traits, and air fungal spore communities on the assembly of the fungi inhabiting Norway spruce needles. We used Norway spruce clones and spore traps within the collection sites and characterized both needle and air mycobiome communities by high-throughput sequencing of the ITS2 region. The composition of the needle mycobiome differed between Norway spruce clones, and clones with high genetic similarity had a more similar mycobiome. The needle mycobiome also varied across sites and was associated with the composition of the local air mycobiome and climate. Phenotypic traits such as diameter at breast height or crown health influenced the needle mycobiome to a lesser extent than host genotype and air mycobiome. Altogether, our results suggest that the needle mycobiome is mainly driven by the host genotype in combination with the composition of the local air spore communities. Our work highlights the role of host intraspecific variation in shaping the mycobiome of trees and provides new insights on the ecological processes structuring fungal communities inhabiting woody plants.


Assuntos
Micobioma , Picea , Fungos/genética , Genótipo , Micobioma/genética , Picea/genética , Picea/microbiologia , Esporos Fúngicos/genética , Árvores/microbiologia
6.
Plant Cell Environ ; 45(8): 2292-2305, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35598958

RESUMO

Pathogenic diseases frequently occur in drought-stressed trees. However, their contribution to the process of drought-induced mortality is poorly understood. We combined drought and stem inoculation treatments to study the physiological processes leading to drought-induced mortality in Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) saplings infected with Heterobasidion annosum s.s. We analysed the saplings' water status, gas exchange, nonstructural carbohydrates (NSCs) and defence responses, and how they related to mortality. Saplings were followed for two growing seasons, including an artificially induced 3-month dormancy period. The combined drought and pathogen treatment significantly increased spruce mortality; however, no interaction between these stressors was observed in pine, although individually each stressor caused mortality. Our results suggest that pathogen infection decreased carbon reserves in spruce, reducing the capacity of saplings to cope with drought, resulting in increased mortality rates. Defoliation, relative water content and the starch concentration of needles were predictors of mortality in both species under drought and pathogen infection. Infection and drought stress create conflicting needs for carbon to compartmentalize the pathogen and to avoid turgor loss, respectively. Heterobasidion annosum reduces the functional sapwood area and shifts NSC allocation patterns, reducing the capacity of trees to cope with drought.


Assuntos
Picea , Pinus sylvestris , Pinus , Basidiomycota , Carbono , Secas , Picea/fisiologia , Pinus sylvestris/fisiologia , Folhas de Planta/fisiologia , Árvores , Água/fisiologia
7.
Photochem Photobiol Sci ; 21(10): 1793-1806, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35788901

RESUMO

The photocatalytic and mechanical performance of TiO2 nanotubular coatings obtained by anodic oxidation of commercial titanium, using an NH4F and 3.5% v/v water in ethylene glycol solution as electrolyte was investigated. After the anodization, the coatings were thermally treated at 450 °C for 2 h. The effects of the anodizing voltage (40-80 V) and NH4F concentration (0.06, 0.15, 0.27 M) on the formation of the nanotube arrays were evaluated. Nanotube diameters (57 to 114 nm), wall thicknesses (4 to 13 nm), and lengths (5 to 17 µm) increased with the anodizing voltage and the NH4F concentration. The photocatalysts were characterized by scanning electron microscopy, glancing incidence X-ray diffraction, and UV-Vis diffuse reflectance spectroscopy. The mechanical properties of the photocatalysts were determined: adhesion using the tape test (ASTM D3359) and erosion resistance through a 3 h accelerated test. The photocatalytic activity of the nanotubes under UV irradiation was evaluated using hexavalent chromium (Cr(VI)) in the presence of ethylenediaminetetraacetic acid (EDTA), using a 1.25 EDTA/Cr(VI) molar ratio solution at pH 2. A complete Cr(VI) transformation after 3 h of irradiation was obtained for all samples, with a better performance than that of an immobilized P25 sample. The photocatalyst obtained with 0.27 M NH4F at 40 V presented a good behavior in adherence and erosion resistance, together with a very good photocatalytic activity. This novel analysis, combining photocatalytic and mechanical tests, proved that the new TiO2 nanotubular coatings could be successfully used as immobilized photocatalysts in photoreactors for water treatment.


Assuntos
Eletrólitos , Titânio , Titânio/química , Ácido Edético , Catálise , Etilenoglicóis
8.
Int Endod J ; 55(10): 967-988, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35821587

RESUMO

BACKGROUND: Current treatment of immature necrotic permanent teeth with a periapical lesion is regenerative endodontics, which is based on tissue engineering under the triade of stem cells, scaffolds and bioactive molecules. OBJECTIVES: This Umbrella Review was aimed to evaluate the success of scaffold and regenerative materials used for the treatment of these teeth, in terms of apical closure, tooth length increase, widening of root canal walls, tissue vitality and periapical lesion repair. METHODS: An extensive literature research was carried out in the Medline, ISI Web of Science, and Scopus databases for relevant systematic reviews matching the keyword search strategy. Based on inclusion and exclusion criteria, reviewers independently rated the quality of each study to determine their level of evidence. Methodological quality assessment of each article was obtained using A Measurement Tool to Assess Systematic Reviews (AMSTAR)-2 tool, and risk of bias was assessed with the Risk of Bias in Systematic Reviews (ROBIS) tool. RESULTS: After removing duplicates, 155 articles were found; from which 133 were excluded for being non-relevant and 15 other due to exclusion criteria. One more was discarded after methodological quality evaluation, for a total of six articles remaining. The most common scaffold used was the blood clot, others used were poly lactic-co-glycolic acid and platelet-rich fibrin matrix. The most common regeneration material used was Mineral Trioxide Aggregate (MTA), followed by Biodentine. An increase in tooth length and widening of root canal walls were reported in all selected studies with different proportions, as well as periapical lesion repair. ROBIS analysis showed that only one article had low bias, two were classified as unclear bias, while the remaining three had high risk of bias. DISCUSSION: An exhaustive literature search was carried out applying language filters, high-quality indexed journals, year of publication, which ensures the best quality articles were included. Blood clot was the most used scaffold as is the most easy to place inside the canal and does not require to extract blood from the patient. The use of MTA and Biodentine as sealing materials has been associated with thickening of canal walls, apical closure and reduced signs and symptoms of apical periodontitis. However, most of the included reviews assessed were case reports and only in a few of them were clinical trials included. There is also a lack of risk of bias analysis in most reviews. CONCLUSION: The blood clot is the most common scaffold used for inducing regeneration during the treatment of immature necrotic teeth. Tooth length increase and widening of root canal walls are the most common criteria used in the studies as success indicators. MTA and Biodentine did not show differences in the results analysed. Quality assessment and bias risk evaluation showed that it is necessary to design better studies with rigorous methodology to recommend a trustable and predictable protocol for the treatment of immature necrotic permanent teeth with periapical lesions. REGISTRATION: International Prospective Register of Systematic Reviews (PROSPERO) CRD42021248404.


Assuntos
Periodontite Periapical , Trombose , Humanos , Necrose da Polpa Dentária/terapia , Periodontite Periapical/terapia , Tratamento do Canal Radicular/métodos , Revisões Sistemáticas como Assunto
9.
Mol Ecol ; 30(18): 4433-4447, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34218489

RESUMO

Trees must cope with the attack of multiple pathogens, often simultaneously during their long lifespan. Ironically, the genetic and molecular mechanisms controlling this process are poorly understood. The objective of this study was to compare the genetic component of resistance in Norway spruce to Heterobasidion annosum s.s. and its sympatric congener Heterobasidion parviporum. Heterobasidion root- and stem-rot is a major disease of Norway spruce caused by members of the Heterobasidion annosum species complex. Resistance to both pathogens was measured using artificial inoculations in half-sib families of Norway spruce trees originating from central to northern Europe. The genetic component of resistance was analysed using 63,760 genome-wide exome-capture sequenced SNPs and multitrait genome-wide associations. No correlation was found for resistance to the two pathogens; however, associations were found between genomic variants and resistance traits with synergic or antagonist pleiotropic effects to both pathogens. Additionally, a latitudinal cline in resistance in the bark to H. annosum s.s. was found; trees from southern latitudes, with a later bud-set and thicker stem diameter, allowed longer lesions, but this was not the case for H. parviporum. In summary, this study detects genomic variants with pleiotropic effects which explain multiple disease resistance from a genic level and could be useful for selection of resistant trees to both pathogens. Furthermore, it highlights the need for additional research to understand the evolution of resistance traits to multiple pathogens in trees.


Assuntos
Basidiomycota , Picea , Basidiomycota/genética , Genômica , Noruega , Picea/genética , Doenças das Plantas/genética
10.
Childs Nerv Syst ; 37(2): 607-615, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32935233

RESUMO

PURPOSE: Deep brain stimulation (DBS) is a common tool for the treatment of movement disorders in adults; however, it remains an emerging treatment modality in children with a growing number of indications, including epilepsy and dystonia. The Child & Youth CompreHensIve Longitudinal Database of DBS (CHILD-DBS) study aims to prospectively collect relevant data on quality of life (QoL), safety, efficacy, and long-term neurodevelopmental outcomes following DBS in children. METHODS: Data are collected and managed using the Research Electronic Data Capture (REDCap). This database aims to collect multicentre comprehensive and longitudinal clinical, QoL, imaging and electrophysiologic data for children under the age of 19 undergoing DBS. RESULTS: Both general and indication-specific measures are collected at baseline and at four time points postoperatively: 6 months, 1 year, 2 years, and 3 years. The database encompasses QoL metrics for children, including the PedsQL (Pediatric Quality of Life Inventory, generic), QOLCE (Quality of Life in Childhood Epilepsy Questionnaire, parent-rated), CHU 9D (Child Health Utility 9D), and KIDSCREEN. Caregiver clinical and QoL metrics, including QIDS (Quick Inventory of Depressive Symptomatology), GAD-7 (Generalized Anxiety Disorder 7-item scale), and CarerQoL-7D (The Care-related Quality of Life Instrument), are similarly prospectively collected. Healthcare resource utilization is also assessed before and after DBS. Lastly, stimulation parameters and radiographic and electrophysiologic data are collected within the database. CONCLUSIONS: The development of the current prospective paediatric DBS database with carefully selected physical and psychosocial outcomes and assessments will complement existing efforts to enhance and facilitate multisite collaboration to further understand the role of DBS in childhood.


Assuntos
Estimulação Encefálica Profunda , Distonia , Distúrbios Distônicos , Adolescente , Adulto , Criança , Distúrbios Distônicos/terapia , Humanos , Qualidade de Vida , Resultado do Tratamento
11.
Chembiochem ; 21(9): 1265-1273, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-31868982

RESUMO

For the last two decades, synthetic biologists have been able to unlock and expand the genetic code, generating proteins with unique properties through the incorporation of noncanonical amino acids (ncAAs). These evolved biomaterials have shown great potential for applications in industrial biocatalysis, therapeutics, bioremediation, bioconjugation, and other areas. Our ability to continue developing such technologies depends on having relatively easy access to ncAAs. However, the synthesis of enantiomerically pure ncAAs in practical quantitates for large-scale processes remains a challenge. Biocatalytic ncAA production has emerged as an excellent alternative to traditional organic synthesis in terms of cost, enantioselectivity, and sustainability. Moreover, biocatalytic synthesis offers the opportunity of coupling the intracellular generation of ncAAs with genetic-code expansion to overcome the limitations of an external supply of amino acid. In this minireview, we examine some of the most relevant achievements of this approach and its implications for improving technological applications derived from synthetic biology.


Assuntos
Aminoácidos/síntese química , Biotecnologia/métodos , Código Genético , Biossíntese de Proteínas , Proteínas/química , Biologia Sintética , Biocatálise
12.
BMC Vet Res ; 16(1): 321, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32873288

RESUMO

BACKGROUND: In an era of unprecedented socio-ecological changes, managing wildlife health demands high-quality data collection and the engagement of local communities. Blastocerus dichotomus, the largest South American deer, is Vulnerable to extinction mainly due to habitat loss. Diseases have been recognised as a potential threat, and winter mortality has been historically described in marsh deer populations from Argentina. Field difficulties have, however, prevented in-depth studies of their health status. RESULTS: Between May 2014 and April 2017, we investigated marsh deer morbidity and mortality in the two largest populations in Argentina. We collected data by means of a passive surveillance system that involved a network of researchers, field partners (veterinarians, park rangers, and local community), and decision makers. We sampled marsh deer during as well as outside mortality events. A total of 44 marsh deer with different body condition scores were evaluated. We obtained haematology and biochemistry values from animals with good body condition score. Marsh deer with poor body condition had a high burden of the ticks Amblyomma triste and Rhipicephalus microplus. Vector-borne agents such as Theileria cervi, Trypanosoma theileri, Trypanosoma evansi, Ehrlichia chaffeensis, Anaplasma platys, Anaplasma odocoilei, Anaplasma marginale, and Candidatus Anaplasma boleense were also found. Haemonchus spp., Ostertagia spp., and Trichostrongylus spp. were the most frequent gastrointestinal parasites in deer with poor body condition. A Multiple Correspondence Analysis reinforced a possible association of winter period with lower body score condition, high tick loads, infection with E. chaffeensis, and presence of harmful gastrointestinal parasites. CONCLUSIONS: Our approach allowed the establishment of a participatory surveillance network of marsh deer morbidity and mortality in Argentina. We report and analyse the first data obtained opportunistically within the framework of this network, providing information on the infectious and parasitic agents in marsh deer populations. The occurrence of Fasciola hepatica and Leptospira interrogans serovar pyrogenes is reported for the first time in wild marsh deer from Argentina. Our data will be useful to improve the interpretation of future mortality events. The field implementation of a surveillance network is key to a holistic approach to wildlife diseases.


Assuntos
Infecções Bacterianas/veterinária , Cervos , Doenças Parasitárias em Animais/parasitologia , Infestações por Carrapato/veterinária , Ferimentos e Lesões/veterinária , Animais , Argentina/epidemiologia , Infecções Bacterianas/microbiologia , Infecções Bacterianas/mortalidade , Fezes/parasitologia , Doenças Parasitárias em Animais/epidemiologia , Doenças Parasitárias em Animais/mortalidade , Dinâmica Populacional , Especificidade da Espécie , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/mortalidade , Ferimentos e Lesões/epidemiologia , Ferimentos e Lesões/mortalidade
13.
Cell Mol Life Sci ; 76(7): 1397-1417, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30673822

RESUMO

Mitochondrial dysfunction represents an important cellular stressor and when intense and persistent cells must unleash an adaptive response to prevent their extinction. Furthermore, mitochondria can induce nuclear transcriptional changes and DNA methylation can modulate cellular responses to stress. We hypothesized that mitochondrial dysfunction could trigger an epigenetically mediated adaptive response through a distinct DNA methylation patterning. We studied cellular stress responses (i.e., apoptosis and autophagy) in mitochondrial dysfunction models. In addition, we explored nuclear DNA methylation in response to this stressor and its relevance in cell survival. Experiments in cultured human myoblasts revealed that intense mitochondrial dysfunction triggered a methylation-dependent pro-survival response. Assays done on mitochondrial disease patient tissues showed increased autophagy and enhanced DNA methylation of tumor suppressor genes and pathways involved in cell survival regulation. In conclusion, mitochondrial dysfunction leads to a "pro-survival" adaptive state that seems to be triggered by the differential methylation of nuclear genes.


Assuntos
Núcleo Celular/genética , Epigênese Genética , Mitocôndrias/metabolismo , Adolescente , Autofagia/efeitos dos fármacos , Estudos de Casos e Controles , Núcleo Celular/metabolismo , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Criança , Pré-Escolar , Metilação de DNA , Epigênese Genética/efeitos dos fármacos , Feminino , Humanos , Masculino , Mitocôndrias/efeitos dos fármacos , Doenças Mitocondriais/genética , Doenças Mitocondriais/metabolismo , Doenças Mitocondriais/patologia , Mioblastos/citologia , Mioblastos/efeitos dos fármacos , Mioblastos/metabolismo , Rotenona/farmacologia
14.
Am J Hum Genet ; 98(1): 90-101, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26686765

RESUMO

Clustered regularly interspaced short palindromic repeat (CRISPR) has arisen as a frontrunner for efficient genome engineering. However, the potentially broad therapeutic implications are largely unexplored. Here, to investigate the therapeutic potential of CRISPR/Cas9 in a diverse set of genetic disorders, we establish a pipeline that uses readily obtainable cells from affected individuals. We show that an adapted version of CRISPR/Cas9 increases the amount of utrophin, a known disease modifier in Duchenne muscular dystrophy (DMD). Furthermore, we demonstrate preferential elimination of the dominant-negative FGFR3 c.1138G>A allele in fibroblasts of an individual affected by achondroplasia. Using a previously undescribed approach involving single guide RNA, we successfully removed large genome rearrangement in primary cells of an individual with an X chromosome duplication including MECP2. Moreover, removal of a duplication of DMD exons 18-30 in myotubes of an individual affected by DMD produced full-length dystrophin. Our findings establish the far-reaching therapeutic utility of CRISPR/Cas9, which can be tailored to target numerous inherited disorders.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Doenças Genéticas Inatas/terapia , Alelos , Expressão Gênica , Doenças Genéticas Inatas/genética , Humanos , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/terapia
17.
Parasitology ; 143(11): 1358-68, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27220254

RESUMO

Establishing the putative links between sylvatic and domestic transmission cycles of Trypanosoma cruzi, the etiological agent of Chagas disease, is of public health relevance. We conducted three surveys to assess T. cruzi infection in wild mammals from a rural and a preserved area in Misiones Province, Northeastern Argentina, which had recently been declared free of vector- and blood-borne transmission of human T. cruzi infection. A total of 200 wild mammals were examined by xenodiagnosis (XD) and/or polymerase chain reaction (PCR) amplification of the hyper-variable region of kinetoplast DNA minicircles of T. cruzi (kDNA-PCR). The overall prevalence of T. cruzi infection was 8%. Nine (16%) of 57 Didelphis albiventris opossums and two (7%) of 29 Desmodus rotundus vampire bats were positive by both XD and kDNA-PCR. Additionally, one D. rotundus positive for T. cruzi by kDNA-PCR tested positive by satellite-DNA-PCR (SAT-DNA-PCR). The T. cruzi-infected bats were captured indoors and in the yard of a vacant dwelling. All D. albiventris were infected with TcI and both XD-positive D. rotundus by TcII. Fifty-five opossum cubs within the marsupium were negative by XD. The mean infectiousness to the vector was 62% in D. albiventris and 50% in D. rotundus. Mice experimentally infected with a parasite isolate from a vampire bat displayed lesions typically caused by T. cruzi. Our study documents the presence of the genotype TcII in a sylvatic host for the first time in Argentina, and the occurrence of two transmission cycles of T. cruzi in a district free of domestic vector-borne transmission.


Assuntos
Doença de Chagas/veterinária , Quirópteros/parasitologia , Reservatórios de Doenças , Mamíferos/parasitologia , Trypanosoma cruzi/isolamento & purificação , Animais , Animais Selvagens/parasitologia , Argentina/epidemiologia , Doença de Chagas/epidemiologia , Doença de Chagas/parasitologia , Doença de Chagas/transmissão , DNA de Protozoário/genética , Vetores de Doenças , Gambás/parasitologia , Reação em Cadeia da Polimerase , Prevalência , Xenodiagnóstico
18.
J Immunol ; 190(8): 3939-48, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23487420

RESUMO

NK cells that populate the decidua are important regulators of normal placentation. In contrast to peripheral blood NK cells, decidual NK (dNK) cells lack cytotoxicity, secrete proangiogenic factors, and regulate trophoblast invasion. In this study we show that exposure to a combination of hypoxia, TGF-ß1, and a demethylating agent results in NK cells that express killer cell Ig-like receptors, the dNK cell markers CD9 and CD49a, and a dNK pattern of chemokine receptors. These cells secrete vascular endothelial growth factor (a potent proangiogenic molecule), display reduced cytotoxicity, and promote invasion of human trophoblast cell lines. These findings have potential therapeutic applications for placental disorders associated with altered NK cell biology.


Assuntos
Proteínas Angiogênicas/fisiologia , Antígeno CD56/fisiologia , Imunofenotipagem , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Receptores de IgG/fisiologia , Receptores KIR/fisiologia , Proteínas Angiogênicas/biossíntese , Proteínas Angiogênicas/sangue , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Antígeno CD56/biossíntese , Antígeno CD56/sangue , Linhagem Celular Transformada , Movimento Celular/imunologia , Grânulos Citoplasmáticos/imunologia , Decídua/citologia , Decídua/imunologia , Decídua/metabolismo , Decitabina , Feminino , Proteínas Ligadas por GPI/biossíntese , Proteínas Ligadas por GPI/sangue , Proteínas Ligadas por GPI/fisiologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Receptores de IgG/biossíntese , Receptores de IgG/sangue , Receptores KIR/biossíntese , Receptores KIR/sangue
19.
J Thromb Thrombolysis ; 39(4): 452-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25052832

RESUMO

Takotsubo cardiomyopathy (TK) includes a transient left ventricular dysfunction without obstructive coronary disease, sometimes after stressful situations with elevated cathecolamines. Since catecholamines activate platelets we aimed to study the platelet influence in a TK setting. We included 32 patients with a TK diagnosis, 13 with an acute coronary syndrome (ACS) and 18 healthy volunteers. Once consent informed was obtained, blood samples were extracted and processed (at admission and after 3 months follow-up). Clinical, ecg, echocardiographic and angiographic features were thoroughly recorded.Previous treatment before admission was similar between groups. No differences were observed in clinical features or any of the acute markers studied regarding platelet reactivity between TK compared to ACS. After follow-up, aggregation levels and platelet reactivity showed differences, mainly due to the antithrombotic therapy prescribed at discharge, but similar to volunteers. Circulating epinephrine during the acute phase was significantly higher in TK (p < 0.001). Patients with higher levels of epinephrine had elevated platelet activation and aggregation after 3 months. No differences were observed in Takotsubo acute platelet aggregation compared to patients with ACS, in spite of higher blood levels of adrenaline. Takotsubo patients had elevated platelet aggregation and activation compared with ACS patients at 3 months follow-up because they were less frequently on chronic clopidogrel and ASA. However, they had similar platelet aggregation and activation levels to healthy volunteers despite treatment with low-dose ASA. Takotsubo patients who had higher levels of adrenaline in the acute phase displayed increased platelet reactivity during follow-up.


Assuntos
Plaquetas/metabolismo , Epinefrina/sangue , Agregação Plaquetária , Sistema de Registros , Cardiomiopatia de Takotsubo/sangue , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Clopidogrel , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/administração & dosagem , Testes de Função Plaquetária , Estudos Prospectivos , Cardiomiopatia de Takotsubo/tratamento farmacológico , Ticlopidina/administração & dosagem , Ticlopidina/análogos & derivados
20.
Chaos ; 25(7): 075409, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26232982

RESUMO

We study diverse scaling and information theory characteristics of Mesoscale Convective Systems (MCSs) as seen by the Tropical Rainfall Measuring Mission (TRMM) over continental and oceanic regions of tropical South America, and 2-D radar rainfall fields from Amazonia. The bi-dimensional Fourier spectra of MCSs exhibit inverse power laws with respect to the spatial scale, whose scaling exponents, ß, capture the type of spatial correlation of rainfall among the study regions, including those over the Andes of Colombia as well as over oceanic and Amazonian regions. The moment-scaling analysis evidences that the structure function deviates from simple scaling at order q > 1.0, thus signaling the multi-scaling nature of rainfall fields within MCSs in tropical South America, with departures from simple scaling associated with the physical characteristics of MCSs over the different study regions. Entropy is estimated for a large set of radar rainfall fields during the distinctive atmospheric regimes (Easterly and Westerly events) in this part of Amazonia. Results evidence that there are significant differences in the dynamics of rainfall among regimes. No clear-cut relationship is found between entropy and the first two statistical moments, but power fits in space and time, S(γ) ∼ γ(-η) for skewness and, S(κ) ∼ κ(-ϵ) for kurtosis. The exponents η and ϵ are statistically different between Easterly and Westerly events, although the significance of fits is less when L-moments are used to estimate skewness and kurtosis. Interesting differences are identified between the time and space generalized q-entropy functions of Amazonian rainfall fields. In both cases, the functions are a continuous set of power laws (analogous to the structure function in turbulence), S(T, q) ∼ T(ß), and, S(λ, q) ∼ λ(ß), covering a broad range of temporal and spatial scales. Both time and space generalized q-entropy functions exhibit linear growth in the range -1.0 < q < -0.5, and saturation of the exponent ß for q ≥ 1.0. In the case of the spatial analysis, the exponent saturates at 〈ß〉∼1.0, whereas at 〈ß〉=0.5 for the temporal case. Results are similar for time series extracted from the S-POL radar and time series of rainfall in tropical Andes. Additionally, differences in values of 〈ß〉 for q ≥ 1.0 between Easterly and Westerly events are not statistically significant.


Assuntos
Monitoramento Ambiental/estatística & dados numéricos , Modelos Químicos , Modelos Estatísticos , Chuva/química , Solo/química , Clima Tropical , Simulação por Computador , Entropia , América do Sul
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