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1.
J Biol Chem ; 299(9): 105164, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37595871

RESUMO

We previously reported that the protein-tyrosine phosphatase SHP-1 (PTPN6) negatively regulates insulin signaling, but its impact on hepatic glucose metabolism and systemic glucose control remains poorly understood. Here, we use co-immunoprecipitation assays, chromatin immunoprecipitation sequencing, in silico methods, and gluconeogenesis assay, and found a new mechanism whereby SHP-1 acts as a coactivator for transcription of the phosphoenolpyruvate carboxykinase 1 (PCK1) gene to increase liver gluconeogenesis. SHP-1 is recruited to the regulatory regions of the PCK1 gene and interacts with RNA polymerase II. The recruitment of SHP-1 to chromatin is dependent on its association with the transcription factor signal transducer and activator of transcription 5 (STAT5). Loss of SHP-1 as well as STAT5 decrease RNA polymerase II recruitment to the PCK1 promoter and consequently PCK1 mRNA levels leading to blunted gluconeogenesis. This work highlights a novel nuclear role of SHP-1 as a key transcriptional regulator of hepatic gluconeogenesis adding a new mechanism to the repertoire of SHP-1 functions in metabolic control.

2.
Clin Infect Dis ; 77(12): 1700-1703, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37477511

RESUMO

Klebsiella oxytoca is a gram-negative bacterium found in fecal microbiota and known to cause several infections in humans, including antibiotic-associated hemorrhagic colitis. We present here a case of colitis caused by K. oxytoca toxin-producing strains that evolved in chronic diarrhea successfully treated by fecal microbiota transplant.


Assuntos
Colite , Enterocolite Pseudomembranosa , Infecções por Klebsiella , Humanos , Klebsiella oxytoca , Antibacterianos/uso terapêutico , Transplante de Microbiota Fecal/efeitos adversos , Infecções por Klebsiella/microbiologia , Enterocolite Pseudomembranosa/etiologia , Diarreia/tratamento farmacológico , Colite/complicações , Colite/tratamento farmacológico
3.
J Virol ; 95(10)2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-33627386

RESUMO

The "omics" revolution of recent years has simplified the study of RNA transcripts produced during viral infection and under specific defined conditions. In the quest to find new and differentially expressed transcripts during the course of human Herpesvirus 6B (HHV-6B) infection, we made use of large-scale RNA sequencing to analyze the HHV-6B transcriptome during productive infection of human Molt-3 T-cells. Analyses were performed at different time points following infection and specific inhibitors were used to classify the kinetic class of each open reading frame (ORF) reported in the annotated genome of HHV-6B Z29 strain. The initial search focussed on HHV-6B-specific reads matching new HHV-6B transcripts. Differential expression of new HHV-6B transcripts were observed in all samples analyzed. The presence of many of these new HHV-6B transcripts were confirmed by RT-PCR and Sanger sequencing. Many of these transcripts represented new splice variants of previously reported ORFs, including some transcripts that have yet to be defined. Overall, our work demonstrates the diversity and the complexity of the HHV-6B transcriptome.IMPORTANCERNA sequencing (RNA-seq) is an important tool for studying RNA transcripts, particularly during active viral infection. We made use of RNA-seq to study human Herpesvirus 6B (HHV-6B) infection. Using six different time points, we were able to identify the presence of differentially spliced genes at 6, 9, 12, 24, 48 and 72 hours post-infection. Determination of the RNA profiles in the presence of cycloheximide (CHX) or phosphonoacetic acid (PAA) also permitted identification of the kinetic class of each ORF described in the annotated GenBank file. We also identified new spliced transcripts for certain genes and evaluated their relative expression over time. These data and next-generation sequencing (NGS) of the viral DNA have led us to propose a new version of the HHV-6B Z29 GenBank annotated file, without changing ORF names in order to facilitate trace back and correlate our work with previous studies on HHV-6B.

4.
Am J Physiol Endocrinol Metab ; 320(2): E259-E269, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33196296

RESUMO

White adipose tissue (WAT) is a dynamic organ that plays crucial roles in controlling metabolic homeostasis. During development and periods of energy excess, adipose progenitors are recruited and differentiate into adipocytes to promote lipid storage capability. The identity of adipose progenitors and the signals that promote their recruitment are still incompletely characterized. We have recently identified V-set and transmembrane domain-containing protein 2A (VSTM2A) as a novel protein enriched in preadipocytes that amplifies adipogenic commitment. Despite the emerging role of VSTM2A in promoting adipogenesis, the molecular mechanisms regulating Vstm2a expression in preadipocytes are still unknown. To define the molecular mechanisms controlling Vstm2a expression, we have treated preadipocytes with an array of compounds capable of modulating established regulators of adipogenesis. Here, we report that Vstm2a expression is positively regulated by PI3K/mTOR and cAMP-dependent signaling pathways and repressed by the MAPK pathway and the glucocorticoid receptor. By integrating the impact of all the molecules tested, we identified signal transducer and activator of transcription 3 (STAT3) as a novel downstream transcription factor affecting Vstm2a expression. We show that activation of STAT3 increased Vstm2a expression, whereas its inhibition repressed this process. In mice, we found that STAT3 phosphorylation is elevated in the early phases of WAT development, an effect that strongly associates with Vstm2a expression. Our findings identify STAT3 as a key transcription factor regulating Vstm2a expression in preadipocytes.NEW & NOTEWORTHY cAMP-dependent and PI3K-mTOR signaling pathways promote the expression of Vstm2a. STAT3 is a key transcription factor that controls Vstm2a expression in preadipocytes. STAT3 is activated in the early phases of WAT development, an effect that strongly associates with Vstm2a expression.


Assuntos
Adipócitos/fisiologia , Adipogenia/genética , Proteínas de Membrana/fisiologia , Fator de Transcrição STAT3/fisiologia , Células 3T3-L1 , Tecido Adiposo Branco/metabolismo , Animais , Diferenciação Celular/genética , Regulação da Expressão Gênica , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Fator de Transcrição STAT3/genética , Transdução de Sinais/genética
5.
J Antimicrob Chemother ; 75(4): 849-858, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31891387

RESUMO

OBJECTIVES: Azole resistance among Aspergillus fumigatus isolates is a growing concern worldwide. Induction of mutations during azole therapy, environment-acquired mutations caused by azole fungicides and intrinsic resistance of cryptic Fumigati species all contribute to the burden of resistance. However, there is a lack of data in Canada on this emerging threat. METHODS: To gain insights into the magnitude and mechanisms of resistance, a 14 year collection of Aspergillus section Fumigati comprising 999 isolates from 807 patients at a Montreal hospital was screened for azole resistance, and resistance mechanisms were investigated with the combined use of genome sequencing, 3D modelling and phenotypic efflux pump assays. RESULTS: Overall azole resistance was low (4/807 patients; 0.5%). A single azole-resistant A. fumigatus sensu stricto strain, isolated from a patient with pulmonary aspergillosis, displayed efflux-pump-mediated resistance. Three patients were colonized or infected with azole-resistant cryptic Fumigati species (one Aspergillus thermomutatus, one Aspergillus lentulus and one Aspergillus turcosus). Evidence is presented that azole resistance is efflux-pump-mediated in the A. turcosus isolate, but not in the A. lentulus and A. thermomutatus isolates. CONCLUSIONS: Azole resistance is rare in our geographic area and currently driven by cryptic Fumigati species. Continued surveillance of emergence of resistance is warranted.


Assuntos
Azóis , Farmacorresistência Fúngica , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Aspergillus/genética , Aspergillus fumigatus/genética , Azóis/farmacologia , Canadá , Proteínas Fúngicas/genética , Humanos , Testes de Sensibilidade Microbiana , Prevalência , Centros de Atenção Terciária
6.
Nucleic Acids Res ; 46(15): 7612-7630, 2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-29905868

RESUMO

CK2 is an essential protein kinase implicated in various cellular processes. In this study, we address a potential role of this kinase in chromatin modulations associated with transcription. We found that CK2 depletion from yeast cells leads to replication-independent increase of histone H3K56 acetylation and global activation of H3 turnover in coding regions. This suggests a positive role of CK2 in maintenance/recycling of the histone H3/H4 tetramers during transcription. Interestingly, strand-specific RNA-seq analyses show that CK2 inhibits global cryptic promoters driving both sense and antisense transcription. This further indicates a role of CK2 in the modulation of chromatin during transcription. Next, we showed that CK2 interacts with the major histone chaperone Spt6, and phosphorylates it in vivo and in vitro. CK2 phosphorylation of Spt6 is required for its cellular levels, for the suppression of histone H3 turnover and for the inhibition of spurious transcription. Finally, we showed that CK2 and Spt6 phosphorylation sites are important to various transcriptional responses suggesting that cryptic intragenic and antisense transcript production are associated with a defective adaptation to environmental cues. Altogether, our data indicate that CK2 mediated phosphorylation of Spt6 regulates chromatin dynamics associated with transcription, and prevents aberrant transcription.


Assuntos
Caseína Quinase II/metabolismo , Chaperonas de Histonas/metabolismo , Histonas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Fatores de Elongação da Transcrição/metabolismo , Acetilação , Caseína Quinase II/genética , Cromatina/genética , Cromatina/metabolismo , Regulação Fúngica da Expressão Gênica , Chaperonas de Histonas/genética , Fosforilação , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Transcrição Gênica , Fatores de Elongação da Transcrição/genética
7.
Eur Arch Otorhinolaryngol ; 277(3): 887-892, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31807892

RESUMO

PURPOSE: Minimally invasive parathyroid surgery and hypnosis are both increasing in prevalence. The objective of this study was to evaluate the efficacy of hypnoanalgesia compared with sedation during primary hyperparathyroid surgery under local anaesthesia. METHODS: All patients who underwent primary hyperparathyroid surgery under local anaesthesia in our department between January 2013 and April 2018 were included retrospectively in two groups: patients operated under hypnoanalgesia (HYP group), and patients operated under sedation (LA group). The evaluation criteria were postoperative pain and analgesic consumption, amount of perioperative anti-emetics required, and length of hospital stay. RESULTS: Thirty-six patients were included, 19 in the HYP group and 17 in the LA group. Postoperative pain levels and analgesic consumption rates were lower in the HYP group (numeric scale = 0.5/10 vs. 2.7/10, p = 0.0001; 11% vs. 47%, p = 4.9 × 10-8). Intraoperative anti-emetics delivery was lower in the HYP group (5% vs. 35%, p = 2.9 × 10-7). The ambulatory care rate was higher in the HYP group (74% vs. 59%, p = 0.03). CONCLUSION: Local anaesthesia with hypnoanalgesia, compared with sedation during minimally invasive parathyroid surgery, improved early postoperative outcomes, making outpatient management more efficient.


Assuntos
Anestesia Local , Hipnose , Analgésicos , Humanos , Dor Pós-Operatória/prevenção & controle , Estudos Retrospectivos
8.
Artigo em Inglês | MEDLINE | ID: mdl-30455248

RESUMO

We analyzed 254 Shigella species isolates collected in Québec, Canada, during 2013 and 2014. Overall, 23.6% of isolates showed reduced susceptibility to azithromycin (RSA) encoded by mphA (11.6%), ermB (1.7%), or both genes (86.7%). Shigella strains with RSA were mostly isolated from men who have sex with men (68.8% or higher) from the Montreal region. A complete sequence analysis of six selected plasmids from Shigella sonnei and different serotypes of Shigella flexneri emphasized the role of IS26 in the dissemination of RSA.


Assuntos
Azitromicina/farmacologia , Shigella/efeitos dos fármacos , Shigella/patogenicidade , Antibacterianos/farmacologia , Canadá , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Masculino , Testes de Sensibilidade Microbiana , Quebeque , Shigella flexneri/efeitos dos fármacos , Shigella flexneri/patogenicidade , Shigella sonnei/efeitos dos fármacos , Shigella sonnei/patogenicidade
9.
BMC Genomics ; 19(1): 438, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29866048

RESUMO

BACKGROUND: Assisted reproductive technologies (ART) are widely used to treat fertility issues in humans and for the production of embryos in mammalian livestock. The use of these techniques, however, is not without consequence as they are often associated with inauspicious pre- and postnatal outcomes including premature birth, intrauterine growth restriction and increased incidence of epigenetic disorders in human and large offspring syndrome in cattle. Here, global DNA methylation profiles in the trophectoderm and embryonic discs of in vitro produced (IVP), superovulation-derived (SOV) and unstimulated, synchronised control day 17 bovine conceptuses (herein referred to as AI) were interrogated using the EmbryoGENE DNA Methylation Array (EDMA). Pyrosequencing was used to validate four loci identified as differentially methylated on the array and to assess the differentially methylated regions (DMRs) of six imprinted genes in these conceptuses. The impact of embryo-production induced DNA methylation aberrations was determined using Ingenuity Pathway Analysis, shedding light on the potential functional consequences of these differences. RESULTS: Of the total number of differentially methylated loci identified (3140) 77.3 and 22.7% were attributable to SOV and IVP, respectively. Differential methylation was most prominent at intragenic sequences within the trophectoderm of IVP and SOV-derived conceptuses, almost a third (30.8%) of the differentially methylated loci mapped to intragenic regions. Very few differentially methylated loci were detected in embryonic discs (ED); 0.16 and 4.9% of the differentially methylated loci were located in the ED of SOV-derived and IVP conceptuses, respectively. The overall effects of SOV and IVP on the direction of methylation changes were associated with increased methylation; 70.6% of the differentially methylated loci in SOV-derived conceptuses and 57.9% of the loci in IVP-derived conceptuses were more methylated compared to AI-conceptuses. Ontology analysis of probes associated with intragenic sequences suggests enrichment for terms associated with cancer, cell morphology and growth. CONCLUSION: By examining (1) the effects of superovulation and (2) the effects of an in vitro system (oocyte maturation, fertilisation and embryo culture) we have identified that the assisted reproduction process of superovulation alone has the largest impact on the DNA methylome of subsequent embryos.


Assuntos
Bovinos/embriologia , Bovinos/genética , Metilação de DNA , Técnicas de Reprodução Assistida , Trofoblastos/metabolismo , Animais , Loci Gênicos/genética
10.
BMC Genomics ; 19(1): 424, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29859035

RESUMO

BACKGROUND: Aberrant DNA methylation patterns of genes required for development are common in in vitro produced embryos. In this regard, we previously identified altered DNA methylation patterns of in vivo developed blastocysts from embryos which spent different stages of development in vitro, indicating carryover effects of suboptimal culture conditions on epigenetic signatures of preimplantation embryos. However, epigenetic responses of in vivo originated embryos to suboptimal culture conditions are not fully understood. Therefore, here we investigated DNA methylation patterns of in vivo derived bovine embryos subjected to in vitro culture condition before, during or after major embryonic genome activation (EGA). For this, in vivo produced 2-, 8- and 16-cell stage embryos were cultured in vitro until the blastocyst stage and blastocysts were used for genome-wide DNA methylation analysis. RESULTS: The 2- and 8-cell flushed embryo groups showed lower blastocyst rates compared to the 16-cell flush group. This was further accompanied by increased numbers of differentially methylated genomic regions (DMRs) in blastocysts of the 2- and 8-cell flush groups compared to the complete in vivo control ones. Moreover, 1623 genomic loci including imprinted genes were hypermethylated in blastocyst of 2-, 8- and 16-cell flushed groups, indicating the presence of genomic regions which are sensitive to the in vitro culture at any stage of embryonic development. Furthermore, hypermethylated genomic loci outnumbered hypomethylated ones in blastocysts of 2- and 16-cell flushed embryo groups, but the opposite occurred in the 8-cell group. Moreover, DMRs which were unique to blastocysts of the 2-cell flushed group and inversely correlated with corresponding mRNA expression levels were involved in plasma membrane lactate transport, amino acid transport and phosphorus metabolic processes, whereas DMRs which were specific to the 8-cell group and inversely correlated with corresponding mRNA expression levels were involved in several biological processes including regulation of fatty acids and steroid biosynthesis processes. CONCLUSION: In vivo embryos subjected to in vitro culture before and during major embryonic genome activation (EGA) are prone to changes in DNA methylation marks and exposure of in vivo embryos to in vitro culture during the time of EGA increased hypomethylated genomic loci in blastocysts.


Assuntos
Blastocisto/metabolismo , Metilação de DNA , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário/genética , Genômica , Animais , Bovinos , Cromossomos de Mamíferos/genética , Análise de Sequência de DNA
11.
J Clin Microbiol ; 56(9)2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29899005

RESUMO

Serratia marcescens is an environmental bacterium that is commonly associated with outbreaks in neonatal intensive care units (NICUs). Investigations of S. marcescens outbreaks require efficient recovery and typing of clinical and environmental isolates. In this study, we investigated how the use of next-generation sequencing applications, such as bacterial whole-genome sequencing (WGS) and bacterial community profiling, could improve S. marcescens outbreak investigations. Phylogenomic links and potential antibiotic resistance genes and plasmids in S. marcescens isolates were investigated using WGS, while bacterial communities and relative abundances of Serratia in environmental samples were assessed using sequencing of bacterial phylogenetic marker genes (16S rRNA and gyrB genes). Typing results obtained using WGS for the 10 S. marcescens isolates recovered during a NICU outbreak investigation were highly consistent with those obtained using pulsed-field gel electrophoresis (PFGE), the current standard typing method for this bacterium. WGS also allowed the identification of genes associated with antibiotic resistance in all isolates, while no plasmids were detected. Sequencing of the 16S rRNA and gyrB genes both showed greater relative abundances of Serratia at environmental sampling sites that were in close contact with infected babies. Much lower relative abundances of Serratia were observed following disinfection of a room, indicating that the protocol used was efficient. Variations in the bacterial community composition and structure following room disinfection and among sampling sites were also identified through 16S rRNA gene sequencing. Together, results from this study highlight the potential for next-generation sequencing tools to improve and to facilitate outbreak investigations.


Assuntos
Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Surtos de Doenças , Técnicas de Diagnóstico Molecular/métodos , Infecções por Serratia/epidemiologia , Infecções por Serratia/microbiologia , Serratia marcescens/isolamento & purificação , DNA Bacteriano/genética , Eletroforese em Gel de Campo Pulsado/normas , Feminino , Marcadores Genéticos/genética , Genoma Bacteriano/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Quebeque/epidemiologia , Análise de Sequência de DNA , Serratia marcescens/classificação , Serratia marcescens/genética
12.
Food Microbiol ; 73: 99-110, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29526232

RESUMO

Salmonella enterica serovar Heidelberg (S. Heidelberg) is one of the top serovars causing human salmonellosis. This serovar ranks second and third among serovars that cause human infections in Québec and Canada, respectively, and has been associated with severe infections. Traditional typing methods such as PFGE do not display adequate discrimination required to resolve outbreak investigations due to the low level of genetic diversity of isolates belonging to this serovar. This study evaluates the ability of four whole genome sequence (WGS)-based typing methods to differentiate among 145 S. Heidelberg strains involved in four distinct outbreak events and sporadic cases of salmonellosis that occurred in Québec between 2007 and 2016. Isolates from all outbreaks were indistinguishable by PFGE. The core genome single nucleotide variant (SNV), core genome multilocus sequence typing (MLST) and whole genome MLST approaches were highly discriminatory and separated outbreak strains into four distinct phylogenetic clusters that were concordant with the epidemiological data. The clustered regularly interspaced short palindromic repeats (CRISPR) typing method was less discriminatory. However, CRISPR typing may be used as a secondary method to differentiate isolates of S. Heidelberg that are genetically similar but epidemiologically unrelated to outbreak events. WGS-based typing methods provide a highly discriminatory alternative to PFGE for the laboratory investigation of foodborne outbreaks.


Assuntos
Tipagem de Sequências Multilocus/métodos , Intoxicação Alimentar por Salmonella/microbiologia , Infecções por Salmonella/microbiologia , Salmonella enterica/isolamento & purificação , Sequenciamento Completo do Genoma/métodos , Técnicas de Tipagem Bacteriana/métodos , Genoma Bacteriano , Humanos , Filogenia , Quebeque/epidemiologia , Intoxicação Alimentar por Salmonella/epidemiologia , Infecções por Salmonella/epidemiologia , Salmonella enterica/classificação , Salmonella enterica/genética
13.
Reprod Fertil Dev ; 29(4): 838-843, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26751019

RESUMO

Monozygotic (MZ) twins are of great interest to elucidate the contributions of pre- and postnatal environmental factors on epigenetics in the expression of complex traits and diseases. Progeny testing recently revealed that MZ twin bulls do not necessarily lead to identical genetic merit estimates (i.e. breeding values). Therefore, to explain differences in offspring productivity of MZ twin bulls despite their identical genetic backgrounds, we hypothesised that paternal sperm epigenomes vary between MZ twin bulls. In the present study, semen characteristics and global sperm DNA methylome were profiled for four pairs of MZ twin bulls. Some MZ twin pairs had divergent semen quality (sperm morphology, motility and viability). Comparative genome-wide DNA methylome surveys were performed using methyl-sensitive enrichment and microarray identification. Between 2% and 10% of all probes (400000) were differentially methylated between MZ twin pairs. In addition, there were 580 loci differentially methylated across all pairs of MZ twins. Furthermore, enrichment analysis indicated a significant enrichment for fertility associated quantitative trait loci (P=0.033). In conclusion, differences in the sperm epigenome may contribute to incongruous diverging performances of daughters sired by bulls that are MZ twins.


Assuntos
Metilação de DNA , Genoma , Espermatozoides/citologia , Espermatozoides/metabolismo , Animais , Bovinos , Forma Celular/fisiologia , Sobrevivência Celular/fisiologia , Masculino , Análise do Sêmen , Motilidade dos Espermatozoides/fisiologia
14.
Physiol Genomics ; 48(8): 633-43, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27401219

RESUMO

Oocyte developmental competence in superstimulated cows is dependent in part on the duration of the FSH coasting. FSH coasting refers to superstimulation with FSH (2 days of endogenous FSH following follicle ablation and 3 days of FSH injections) followed by no FSH for a specific duration. The optimal duration varies among individuals. FSH coasting appears to modulate the transcriptome of different follicular compartments, which cooperate as a single functional unit. However, the integrative effects of FSH coasting on different follicular compartments remain ambiguous. Meta-analysis of three independent transcriptome studies, each focused on a single cell type (granulosa, cumulus, and oocyte) during FSH coasting, allowed the identification of 12 gene clusters with similar time-course expression patterns in all three compartments. Network analysis identified HNF4A (involved in metabolic functions) and ELAVL1 (an RNA-binding protein) as hub genes regulated respectively upward and downward in the clusters enriched at the optimal coasting time, and APP (involved in mitochondrial functions) and COPS5 (a member of the COP9 signalosome) as hub genes regulated respectively upwards and downwards in the clusters enriched progressively throughout the coasting period. We confirmed the effects on HNF4A downstream targets (TTR, PPL) and other hub genes (ELAVL1, APP, MYC, and PGR) in 30 cows with RT-quantitative PCR. The correlation of hub gene expression levels with FSH coasting indicated that a combination of these genes could predict oocyte competence with 83% sensitivity, suggesting that they are potential biomarkers of follicle differentiation. These findings could be used to optimize FSH coasting on an individual basis.


Assuntos
Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Folículo Ovariano/metabolismo , Transcriptoma/fisiologia , Animais , Bovinos , Feminino , Hormônio Foliculoestimulante/metabolismo , Perfilação da Expressão Gênica/métodos
15.
Biol Reprod ; 94(1): 16, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26586844

RESUMO

So far, the characteristics of a good quality egg have been elusive, similar to the nature of the physiological, cellular, and molecular cues leading to its production both in vivo and in vitro. Current understanding highlights a strong and complex interdependence between the follicular cells and the gamete. Secreted factors induce cellular responses in the follicular cells, and direct exchange of small molecules from the cumulus cells to the oocyte through gap junctions controls meiotic arrest. Studying the interconnection between the cumulus cells and the oocyte, we previously demonstrated that the somatic cells also contribute transcripts to the gamete. Here, we show that these transcripts can be visualized moving down the transzonal projections (TZPs) to the oocyte, and that a time course analysis revealed progressive RNA accumulation in the TZPs, indicating that RNA transfer occurs before the initiation of meiosis resumption under a timetable fitting with the acquisition of developmental competence. A comparison of the identity of the nascent transcripts trafficking in the TZPs, with those in the oocyte increasing in abundance during maturation, and that are present on the oocyte's polyribosomes, revealed transcripts common to all three fractions, suggesting the use of transferred transcripts for translation. Furthermore, the removal of potential RNA trafficking by stripping the cumulus cells caused a significant reduction in maturation rates, indicating the need for the cumulus cell RNA transfer to the oocyte. These results offer a new perspective to the determinants of oocyte quality and female fertility, as well as provide insight that may eventually be used to improve in vitro maturation conditions.


Assuntos
Células do Cúmulo/metabolismo , Oócitos/metabolismo , Animais , Bovinos , Células do Cúmulo/ultraestrutura , Feminino , Fertilidade , Regulação da Expressão Gênica , Biblioteca Genômica , Células Germinativas , Meiose , Oócitos/ultraestrutura , Oogênese/fisiologia , Folículo Ovariano/citologia , Polirribossomos , RNA/biossíntese , RNA/genética
16.
Reproduction ; 151(6): R103-10, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26980808

RESUMO

Folliculogenesis involves coordinated profound changes in different follicular compartments and significant modifications of their gene expression patterns, particularly in granulosa cells. Huge datasets have accumulated from the analyses of granulosa cell transcriptomic signatures in predefined physiological contexts using different technological platforms. However, no comprehensive overview of folliculogenesis is available. This would require integration of datasets from numerous individual studies. A prerequisite for such integration would be the use of comparable platforms and experimental conditions. The EmbryoGENE program was created to study bovine granulosa cell transcriptomics under different physiological conditions using the same platform. Based on the data thus generated so far, we present here an interactive web interface called GranulosaIMAGE (Integrative Meta-Analysis of Gene Expression), which provides dynamic expression profiles of any gene of interest and all isoforms thereof in granulosa cells at different stages of folliculogenesis. GranulosaIMAGE features two kinds of expression profiles: gene expression kinetics during bovine folliculogenesis from small (6 mm) to pre-ovulatory follicles under different hormonal and physiological conditions and expression profiles of granulosa cells of dominant follicles from post-partum cows in different metabolic states. This article provides selected examples of expression patterns along with suggestions for users to access and generate their own patterns using GranulosaIMAGE. The possibility of analysing gene expression dynamics during the late stages of folliculogenesis in a mono-ovulatory species such as bovine should provide a new and enriched perspective on ovarian physiology.


Assuntos
Células da Granulosa/metabolismo , Metanálise como Assunto , Folículo Ovariano/citologia , Folículo Ovariano/metabolismo , Transcriptoma , Animais , Feminino , Células da Granulosa/citologia
17.
Mol Reprod Dev ; 83(6): 558-69, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27127921

RESUMO

Follicle size is recognized as a predictor of the potential for the enclosed oocyte to yield an embryo following in vitro maturation and in vitro fertilization. Oocytes from larger follicles are more likely to reach the blastocyst stage than those from smaller follicles. A growing oocyte accumulates all the transcripts needed to ensure development until the maternal embryonic transition, and this accumulation must be completed before the period of transcriptional arrest. Accordingly, the transcriptomes of bovine germinal-vesicle-stage oocytes collected from follicles of increasing sizes (<3, 3-5, >5-8, and >8 mm) were evaluated, using the EmbryoGENE bovine transcriptomic platform (custom Agilent 4 × 44 K), to better understand transcriptional modulation in the oocyte as the follicle becomes larger. Microarray analyses revealed very few differences between oocytes from small follicles (<3 vs. 3-5 mm), whereas an important number of differences were detected at the mRNA level between oocytes from larger follicles. Weighted gene correlation network analysis allowed for the identification of several hub genes involved in crucial functions such as transcriptional regulation (TAF2), chromatin remodeling (PPP1CB), energy production (SLC25A31), as well as transport of key molecules within the cell (NAGPA, CYHR1, and SLC3A12). The results presented here thus reinforce the hypothesis that developmental competence acquisition cannot be seen as a simple one-step process, especially in regards to the modulation of mRNA. Mol. Reprod. Dev. 83: 558-569, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Regulação da Expressão Gênica/fisiologia , Oócitos/metabolismo , Folículo Ovariano/metabolismo , Transcrição Gênica/fisiologia , Animais , Bovinos , Feminino , Perfilação da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos , Oócitos/citologia , Folículo Ovariano/citologia
18.
Environ Sci Technol ; 50(4): 2044-53, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26760055

RESUMO

This project investigates the energy-water usage efficiency of large scale civil infrastructure projects involving the artificial recharge of subsurface groundwater aquifers via the reuse of treated municipal wastewater. A modeling framework is introduced which explores the various ways in which spatially heterogeneous variables such as topography, landuse, and subsurface infiltration capacity combine to determine the physical layout of proposed reuse system components and their associated process energy-water demands. This framework is applied to the planning and evaluation of the energy-water usage efficiency of hypothetical reuse systems in five case study regions within the State of California. Findings from these case study analyses suggest that, in certain geographic contexts, the water requirements attributable to the process energy consumption of a reuse system can exceed the volume of water that it is able to recover by as much as an order of magnitude.


Assuntos
Água Subterrânea , Eliminação de Resíduos Líquidos , California , Fontes Geradoras de Energia , Águas Residuárias , Purificação da Água , Abastecimento de Água
19.
J Clin Microbiol ; 53(3): 967-72, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25520447

RESUMO

We report a new hepatitis C virus (HCV) genotype identified in patients originating from the Democratic Republic of Congo. The prototype QC69 virus is shown to be a new lineage distinct from genotypes 1 to 6. Three additional patients were also found to be infected by a virus from this lineage, confirming its circulation in humans. We propose that these viruses be classified into HCV genotype 7.


Assuntos
Genótipo , Hepacivirus/classificação , Hepacivirus/genética , Hepatite C/virologia , Adolescente , África Central/epidemiologia , Análise por Conglomerados , Feminino , Hepacivirus/isolamento & purificação , Hepatite C/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico
20.
J Environ Manage ; 156: 23-30, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25794964

RESUMO

Development of natural landscapes to support human activities impacts the capacity of the landscape to provide ecosystem services. Typically, several ecosystem services are impacted at a single development site and various footprint scenarios are possible, thus a multi-criteria analysis is needed. Restoration potential should also be considered for the area surrounding the permanent impact site. The primary objective of this research was to develop a heuristic approach to analyze multiple criteria (e.g. impacts to various ecosystem services) in a spatial configuration with many potential development sites. The approach was to: (1) quantify the magnitude of terrestrial ecosystem service (biodiversity, carbon sequestration, nutrient and sediment retention, and pollination) impacts associated with a suite of land use change scenarios using the InVEST model; (2) normalize results across categories of ecosystem services to allow cross-service comparison; (3) apply the multi-criteria heuristic algorithm to select sites with the least impact to ecosystem services, including a spatial criterion (separation between sites). As a case study, the multi-criteria impact minimization algorithm was applied to InVEST output to select 25 potential development sites out of 204 possible locations (selected by other criteria) within a 24,000 ha property. This study advanced a generally applicable spatial multi-criteria approach for 1) considering many land use footprint scenarios, 2) balancing impact decisions across a suite of ecosystem services, and 3) determining the restoration potential of ecosystem services after impacts.


Assuntos
Ecossistema , Modelos Teóricos , Algoritmos , Biodiversidade , Sequestro de Carbono , Conservação dos Recursos Naturais/métodos , Heurística , Humanos , Polinização
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