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Astrocytes play a critical role in brain function, but their contribution during ethanol (EtOH) consumption remains largely understudied. In light of recent findings on the heterogeneity of astrocyte physiology and gene expression, an approach with the ability to identify subtypes and capture this heterogeneity is necessary. Here, we combined measurements of calcium signaling and gene expression to define EtOH-induced astrocyte subtypes. In the absence of a demonstrated EtOH receptor, EtOH is believed to have effects on the function of many receptors and downstream biological cascades that underlie calcium responsiveness. This mechanism of EtOH-induced calcium signaling is unknown and this study provides the first step in understanding the characteristics of cells displaying these observed responses. To characterize underlying astrocyte subtypes, we assessed the correlation between calcium signaling and astrocyte gene expression signature in response to EtOH. We found that various EtOH doses increased intracellular calcium levels in a subset of astrocytes, distinguishing three cellular response types and one nonresponsive subtype as categorized by response waveform properties. Furthermore, single-cell RNA-seq analysis of astrocytes from the different response types identified type-enriched discriminatory gene expression signatures. Combining single-cell calcium responses and gene expression analysis identified specific astrocyte subgroups among astrocyte populations defined by their response to EtOH. This result provides a basis for identifying the relationship between astrocyte susceptibility to EtOH and corresponding measurable markers of calcium signaling and gene expression, which will be useful to investigate potential subgroup-specific influences of astrocytes on the physiology and pathology of EtOH exposure in the brain.
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Astrócitos , Sinalização do Cálcio , Etanol , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Encéfalo/metabolismo , Cálcio/metabolismo , Etanol/farmacologiaRESUMO
Antibodies play a pivotal role against viral infection, and maintenance of protection is dependent on plasma and memory B-cells. Understanding antigen-specific B-cell responses in cattle is essential to inform future vaccine design. We have previously defined T-cell-dependent and -independent B-cell responses in cattle, as a prelude to investigating foot-and-mouth-disease-virus (FMDV)-specific B-cell responses. In this study, we have used an FMDV O-serotype vaccination (O1-Manisa or O SKR) and live-virus challenge (FMDV O SKR) to investigate the homologous and heterologous B-cell response in cattle following both vaccination and live-virus challenge. The FMDV O-serotype vaccines were able to induce a cross-reactive plasma-cell response, specific for both O1-Manisa and O SKR, post-vaccination. Post-FMDV O SKR live-virus challenge, the heterologous O1-Manisa vaccination provided cross-protection against O SKR challenge and cross-reactive O SKR-specific plasma cells were induced. However, vaccination and live-virus challenge were not able to induce a detectable FMDV O-serotype-specific memory B-cell response in any of the cattle. The aim of new FMDV vaccines should be to induce memory responses and increased duration of immunity in cattle.
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Linfócitos B/imunologia , Vírus da Febre Aftosa/imunologia , Febre Aftosa/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Bovinos , Proteção Cruzada , Reações Cruzadas , Memória Imunológica , Vacinas Virais/administração & dosagemRESUMO
Purification of recombinant proteins constitutes a significant part of the downstream processing in biopharmaceutical industries. Major costs involved in the production of bio-therapeutics mainly depend on the number of purification steps used during the downstream process. Affinity chromatography is a widely used method for the purification of recombinant proteins expressed in different expression host platforms. Recombinant protein purification is achieved by fusing appropriate affinity tags to either N- or C- terminus of the target recombinant proteins. Currently available protein/peptide affinity tags have proved quite useful in the purification of recombinant proteins. However, these affinity tags suffer from specific limitations in their use under different conditions of purification. In this study, we have designed a novel 34-amino acid heparin-binding affinity tag (HB-tag) for the purification of recombinant proteins expressed in Escherichia coli (E. coli) cells. HB-tag fused recombinant proteins were overexpressed in E. coli in high yields. A one-step heparin-Sepharose-based affinity chromatography protocol was developed to purify HB-fused recombinant proteins to homogeneity using a simple sodium chloride step gradient elution. The HB-tag has also been shown to facilitate the purification of target recombinant proteins from their 8 M urea denatured state(s). The HB-tag has been demonstrated to be successfully released from the fusion protein by an appropriate protease treatment to obtain the recombinant target protein(s) in high yields. Results of the two-dimensional NMR spectroscopy experiments indicate that the purified recombinant target protein(s) exist in the native conformation. Polyclonal antibodies raised against the HB-peptide sequence, exhibited high binding specificity and sensitivity to the HB-fused recombinant proteins (â¼10 ng) in different crude cell extracts obtained from diverse expression hosts. In our opinion, the HB-tag provides a cost-effective, rapid, and reliable avenue for the purification of recombinant proteins in heterologous hosts.
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Proteínas de Arabidopsis , Arabidopsis/genética , Cromatografia de Afinidade/métodos , Heparina/química , Proteínas Recombinantes de Fusão , Arabidopsis/metabolismo , Proteínas de Arabidopsis/biossíntese , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/isolamento & purificação , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificaçãoRESUMO
Despite the recognized importance of the dorsal raphe (DR) serotonergic (5-HT) nuclei in the pathophysiology of depression and anxiety, the molecular components/putative drug targets expressed by these neurons are poorly characterized. Utilizing the promoter of an ETS domain transcription factor that is a stable marker of 5-HT neurons (Pet-1) to drive 5-HT neuronal expression of YFP, we identified 5-HT neurons in live acute slices. We isolated RNA from single 5-HT neurons in the ventromedial and lateral wings of the DR and performed single-cell RNA-Seq analysis identifying >500 G-protein coupled receptors (GPCRs) including receptors for classical transmitters, lipid signals, and peptides as well as dozens of orphan-GPCRs. Using these data to inform our selection of receptors to assess, we found that oxytocin and lysophosphatidic acid 1 receptors are translated and active in costimulating, with the α1-adrenergic receptor, the firing of DR 5-HT neurons, while the effects of histamine are inhibitory and exerted at H3 histamine receptors. The inhibitory histamine response provides evidence for tonic in vivo histamine inhibition of 5-HT neurons. This study illustrates that unbiased single-cell transcriptomics coupled with functional analyses provides novel insights into how neurons and neuronal systems are regulated.
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Neurônios Serotoninérgicos/metabolismo , Animais , Eletrofisiologia , Técnicas In Vitro , Masculino , Camundongos , Receptores Acoplados a Proteínas G/metabolismo , Serotonina/metabolismoRESUMO
The Society for Neuroscience recognized Baldwin Wallace University's (BWU) undergraduate Neuroscience program as their Program of the Year for 2012. This award acknowledged the "accomplishments of a neuroscience department or program for excellence in educating neuroscientists and providing innovative models to which other programs can aspire." The Neuroscience program grew out of students interested in studying the biological basis of behavior. BWU's neuroscience major is research-intensive, and all students are required to produce an empirically-based senior thesis. This requirement challenges program resources, and the demand for faculty attention is high. Thus, we developed an intentional 3-step peer mentoring system that encourages our students to collaborate with and learn from, not only faculty, but each other. Peer mentoring occurs in the curriculum, faculty research labs, and as students complete their senior theses. As the program has grown with over 80 current majors, we have developed a new Neuroscience Methods course to train students on the safety, ethics, and practice of research in the neuroscience laboratory space. Students in this course leave with the skills and knowledge to assist senior level students with their theses and to begin the process of developing their own projects in the laboratory. Further, our students indicate that their "peer mentorship was excellent," "helped them gain confidence," and "allowed them to be more successful in their research."
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This study is the first to investigate the presence and movement of the novel Liberibacter species 'Candidatus Liberibacter brunswickensis' (CLbr) in eggplant, Solanum melongena. The psyllid, Acizzia solanicola can transmit CLbr to eggplant and CLbr can be acquired by CLbr-negative A. solanicola individuals from CLbr-positive eggplants. In planta, CLbr can replicate, move and persist. Investigation into the early development of eggplants showed that CLbr titres had increased at the inoculation site at 14 days post inoculation access period (DPIAP). CLbr had become systemic in the majority of plants tested by 28 DPIAP. The highest bacterial titres were recorded at 35 DPIAP in all samples of the inoculated leaf, the roots, stems and the midrib and petiole samples of the newest leaf (the top leaf). This finding strongly suggests that CLbr movement in planta follows the source to sink relationship as previously described for 'Ca. Liberibacter asiaticus' (CLas) and 'Ca. Liberibacter solanacearum' (CLso). No symptoms consistent with Liberibacter-associated diseases were noted for plants colonised by CLbr during this study, consistent with the hypothesis that CLbr does not cause disease of eggplant during the early stages of host colonisation. In addition, no significant differences in biomass were found between eggplant colonised with CLbr, compared to those that were exposed to CLbr-negative A. solanicola, and to control plants.
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Doenças das Plantas , Solanum melongena , Solanum melongena/microbiologia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Rhizobiaceae/fisiologia , Liberibacter , Hemípteros/microbiologia , Hemípteros/crescimento & desenvolvimento , Animais , Raízes de Plantas/microbiologiaRESUMO
Streptococcus dysgalactiae subspecies equisimilis (SDSE) and Streptococcus pyogenes share skin and throat niches with extensive genomic homology and horizontal gene transfer (HGT) possibly underlying shared disease phenotypes. It is unknown if cross-species transmission interaction occurs. Here, we conduct a genomic analysis of a longitudinal household survey in remote Australian First Nations communities for patterns of cross-species transmission interaction and HGT. Collected from 4547 person-consultations, we analyse 294 SDSE and 315 S. pyogenes genomes. We find SDSE and S. pyogenes transmission intersects extensively among households and show that patterns of co-occurrence and transmission links are consistent with independent transmission without inter-species interference. We identify at least one of three near-identical cross-species mobile genetic elements (MGEs) carrying antimicrobial resistance or streptodornase virulence genes in 55 (19%) SDSE and 23 (7%) S. pyogenes isolates. These findings demonstrate co-circulation of both pathogens and HGT in communities with a high burden of streptococcal disease, supporting a need to integrate SDSE and S. pyogenes surveillance and control efforts.
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Transferência Genética Horizontal , Sequências Repetitivas Dispersas , Infecções Estreptocócicas , Streptococcus pyogenes , Streptococcus , Streptococcus pyogenes/genética , Streptococcus pyogenes/isolamento & purificação , Streptococcus pyogenes/classificação , Infecções Estreptocócicas/transmissão , Infecções Estreptocócicas/microbiologia , Humanos , Streptococcus/genética , Streptococcus/isolamento & purificação , Sequências Repetitivas Dispersas/genética , Austrália , Genoma Bacteriano/genética , Feminino , Masculino , Criança , Características da Família , Adulto , Pré-Escolar , Adolescente , Estudos Longitudinais , Farmacorresistência Bacteriana/genética , Adulto JovemRESUMO
Streptococcus dysgalactiae subsp. equisimilis (SDSE) is an emerging cause of human infection with invasive disease incidence and clinical manifestations comparable to the closely related species, Streptococcus pyogenes. Through systematic genomic analyses of 501 disseminated SDSE strains, we demonstrate extensive overlap between the genomes of SDSE and S. pyogenes. More than 75% of core genes are shared between the two species with one third demonstrating evidence of cross-species recombination. Twenty-five percent of mobile genetic element (MGE) clusters and 16 of 55 SDSE MGE insertion regions were shared across species. Assessing potential cross-protection from leading S. pyogenes vaccine candidates on SDSE, 12/34 preclinical vaccine antigen genes were shown to be present in >99% of isolates of both species. Relevant to possible vaccine evasion, six vaccine candidate genes demonstrated evidence of inter-species recombination. These findings demonstrate previously unappreciated levels of genomic overlap between these closely related pathogens with implications for streptococcal pathobiology, disease surveillance and prevention.
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Infecções Estreptocócicas , Streptococcus , Vacinas , Humanos , Streptococcus pyogenes/genética , Fluxo GênicoRESUMO
Vibrio alginolyticus causes vibriosis of marine vertebrates, invertebrates, and humans, and while there have been several reports of multidrug resistance in V. alginolyticus, carbapenem resistance is rare. V. alginolyticus strain AUSMDU00064140 was isolated in Melbourne, Australia, from imported prawns. Routine genomic surveillance detected the presence of a full-length blaNDM-1 gene, subsequently shown to be collocated with additional acquired antimicrobial resistance genes on a resistance cassette on the largest chromosome, flanked by mobilization gene annotations. Comparisons to a previously described V. alginolyticus plasmid, pC1349, revealed differing gene content and arrangements between the resistance cassettes. Phylogenetic analysis was performed against a local and global data set (n = 109), demonstrating that AUSMDU00064140 was distinct and did not cluster with any other strains. Despite the presence of the complete blaNDM-1 gene and positive phenotypic assays for carbapenemase production, carbapenem MICs were low (meropenem MIC ≤0.5 mg/liter). However, it is still possible that this gene may be transferred to another species in the environment or a host, causing phenotypic carbapenem resistance and presenting a risk of great public health concern. IMPORTANCE Carbapenems are last-line antimicrobials, vital for use in human medicine. Antimicrobial resistance determinants such as blaNDM (New Delhi metallo-ß-lactamase producing) genes conferring resistance to the carbapenem class of antimicrobials, are typically found in Enterobacterales (first described in 2009 from a Klebsiella pneumoniae isolate). Our study shows that Vibrio alginolyticus isolated from cooked prawn is able to harbor antimicrobial resistance (AMR) genes of public health concern, specifically a chromosomally located blaNDM-1 gene, and there is the potential for transmission of resistance genes. This may be linked with antimicrobial use in low- and middle-income settings, which has typically been high, unregulated, or not reported. Many countries, including Thailand, have implemented national strategic plans to incorporate the World Health Organization (WHO)'s Global Action Plan (2015) recommendations of a global One Health approach, including increased resources for surveillance of antimicrobial usage and AMR; however, efficient antimicrobial surveillance systems incorporating genomic and phenotypic testing of isolates are still lacking in many jurisdictions.
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Antibacterianos , Vibrio alginolyticus , Animais , Humanos , Antibacterianos/farmacologia , Vibrio alginolyticus/genética , Vibrio alginolyticus/metabolismo , Filogenia , Farmacorresistência Bacteriana Múltipla/genética , beta-Lactamases/genética , beta-Lactamases/metabolismo , Carbapenêmicos , Plasmídeos/genética , Klebsiella pneumoniae/genética , Testes de Sensibilidade MicrobianaRESUMO
BACKGROUND: Streptococcus pyogenes, or group A Streptococcus (GAS), infections contribute to a high burden of disease in Aboriginal Australians, causing skin infections and immune sequelae such as rheumatic heart disease. Controlling skin infections in these populations has proven difficult, with transmission dynamics being poorly understood. We aimed to identify the relative contributions of impetigo and asymptomatic throat carriage to GAS transmission. METHODS: In this genomic analysis, we retrospectively applied whole genome sequencing to GAS isolates that were collected as part of an impetigo surveillance longitudinal household survey conducted in three remote Aboriginal communities in the Northern Territory of Australia between Aug 6, 2003, and June 22, 2005. We included GAS isolates from all throats and impetigo lesions of people living in two of the previously studied communities. We classified isolates into genomic lineages based on pairwise shared core genomes of more than 99% with five or fewer single nucleotide polymorphisms. We used a household network analysis of epidemiologically and genomically linked lineages to quantify the transmission of GAS within and between households. FINDINGS: We included 320 GAS isolates in our analysis: 203 (63%) from asymptomatic throat swabs and 117 (37%) from impetigo lesions. Among 64 genomic lineages (encompassing 39 emm types) we identified 264 transmission links (involving 93% of isolates), for which the probable source was asymptomatic throat carriage in 166 (63%) and impetigo lesions in 98 (37%). Links originating from impetigo cases were more frequent between households than within households. Households were infected with GAS for a mean of 57 days (SD 39 days), and once cleared, reinfected 62 days (SD 40 days) later. Increased household size and community presence of GAS and scabies were associated with slower clearance of GAS. INTERPRETATION: In communities with high prevalence of endemic GAS-associated skin infection, asymptomatic throat carriage is a GAS reservoir. Public health interventions such as vaccination or community infection control programmes aimed at interrupting transmission of GAS might need to include consideration of asymptomatic throat carriage. FUNDING: Australian National Health and Medical Research Council.
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Impetigo , Dermatopatias Infecciosas , Infecções Estreptocócicas , Humanos , Impetigo/epidemiologia , Streptococcus pyogenes/genética , Estudos Retrospectivos , Faringe , Northern Territory/epidemiologia , Infecções Estreptocócicas/epidemiologia , GenômicaRESUMO
Genome-wide association studies have identified 2p13.1 as a prominent susceptibility locus for systemic lupus erythematosus (SLE)a complex, multisystem autoimmune disease. However, the identity of underlying causal variant (s) and molecular mechanisms for increasing disease susceptibility are poorly understood. Using meta-analysis (cases = 10,252, controls = 21,604) followed by conditional analysis, bioinformatic annotation, and eQTL and 3D-chromatin interaction analyses, we computationally prioritized potential functional variants and subsequently experimentally validated their effects. Ethnicity-specific meta-analysis revealed striking allele frequency differences between Asian and European ancestries, but with similar odds ratios. We identified 20 genome-wide significant (p < 5 × 10−8) variants, and conditional analysis pinpointed two potential functional variants, rs6705628 and rs2272165, likely to explain the association. The two SNPs are near DGUOK, mitochondrial deoxyguanosine kinase, and its associated antisense RNA DGUOK-AS1. Using luciferase reporter gene assays, we found significant cell type- and allele-specific promoter activity at rs6705628 and enhancer activity at rs2272165. This is supported by ChIP-qPCR showing allele-specific binding with three histone marks (H3K27ac, H3K4me3, and H3K4me1), RNA polymerase II (Pol II), transcriptional coactivator p300, CCCTC-binding factor (CTCF), and transcription factor ARID3A. Transcriptome data across 28 immune cell types from Asians showed both SNPs are cell-type-specific but only in B-cells. Splicing QTLs showed strong regulation of DGUOK-AS1. Genotype-specific DGOUK protein levels are supported by Western blots. Promoter capture Hi-C data revealed long-range chromatin interactions between rs2272165 and several nearby promoters, including DGUOK. Taken together, we provide mechanistic insights into how two noncoding variants underlie SLE risk at the 2p13.1 locus.
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Estudo de Associação Genômica Ampla , Lúpus Eritematoso Sistêmico , Cromatina/genética , Humanos , Lúpus Eritematoso Sistêmico/genética , Polimorfismo de Nucleotídeo Único , Locos de Características QuantitativasRESUMO
The activated clotting time (ACT) assay is used to monitor and titrate anticoagulation therapy with unfractionated heparin during percutaneous coronary intervention (PCI). Observations at our institution suggested a considerable difference between ACT values drawn from varying arterial sites, prompting the current study. Patients undergoing PCI with unfractionated heparin therapy were prospectively enrolled. Simultaneous arterial blood samples were drawn from the access sheath and the coronary guide catheter. Differences between Hemochron ACT values were determined, and potential interactions with clinical variables were analyzed. Immediately postprocedure, the simultaneous mean guide and sheath ACTs were 327 ± 62 seconds and 257 ± 44 seconds, respectively, with a mean difference of 70 ± 60 seconds (P < .001). Nearly all (90%) ACT values obtained via the guide catheter were higher than the concurrent ACT drawn from the sheath. Logistic regression analysis demonstrated that lower weight-adjusted heparin doses and absence of diabetes were associated with a greater difference between the ACT values. We conclude that the ACT value is substantially greater when assessed via the guide catheter versus the access sheath. Although the biological mechanisms require further study, this difference should be considered when managing anticoagulation during PCI and when reporting ACT as part of research protocols.
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Anticoagulantes/uso terapêutico , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/cirurgia , Heparina/uso terapêutico , Intervenção Coronária Percutânea , Idoso , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tempo de Coagulação do Sangue TotalRESUMO
Ethanol (EtOH) abuse induces significant mortality and morbidity worldwide because of detrimental effects on brain function. Defining the contribution of astrocytes to this malfunction is imperative to understanding the overall EtOH effects due to their role in homeostasis and EtOH-seeking behaviors. Using a highly controllable in vitro system, we identify chemical signaling mechanisms through which acute EtOH exposure induces a modulatory feedback loop between neurons and astrocytes. Neuronally-derived purinergic signaling primed a subpopulation of astrocytes to respond to subsequent acute EtOH exposures (SEastrocytes: signal enhanced astrocytes) with greater calcium signal strength. Generation of SEastrocytes arose from astrocytic hemichannel-derived ATP and accumulation of its metabolite adenosine within the astrocyte microenvironment to modulate adenylyl cyclase and phospholipase C activity. These results highlight an important role of astrocytes in shaping the overall physiological responsiveness to EtOH and emphasize the unique plasticity of astrocytes to adapt to single and multiple exposures of EtOH.
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A recent clinical report has linked Streptococcus pyogenes ß-lactam antibiotic resistance to mutation in the penicillin binding protein (PBP) PBP2x. To determine whether this is an isolated case or reflects a broader prevalence of mutations that might confer reduced ß-lactam susceptibility, we investigated the relative frequency of PBP sequence variation within a global database of 9,667 S. pyogenes isolates. We found that mutations in S. pyogenes PBPs (PBP2x, PBP1a, PBP1b, and PBP2a) occur infrequently across this global database, with fewer than 3 amino acid changes differing between >99% of the global population. Only 4 of the 9,667 strains contained mutations near transpeptidase active sites of PBP2x or PBP1a. The reported PBP2x T553K substitution was not identified. These findings are in contrast to those of 2,520 S. pneumococcus sequences where PBP mutations are relatively frequent and are often located in key ß-lactam binding pockets. These data, combined with the general lack of penicillin resistance reported in S. pyogenes worldwide, suggests that extensive, unknown constraints restrict S. pyogenes PBP sequence plasticity. Our findings imply that while heavy antibiotic pressure may select for mutations in the PBPs, there is currently no evidence of such mutations becoming fixed in the S. pyogenes population or that mutations are being sequentially acquired in the PBPs.IMPORTANCE ß-Lactam antibiotics are the first-line therapeutic option for Streptococcus pyogenes infections. Despite the global high prevalence of S. pyogenes infections and widespread use of ß-lactams worldwide, reports of resistance to ß-lactam antibiotics, such as penicillin, have been incredibly rare. Recently, ß-lactam resistance, as defined by clinical breakpoints, was detected in two clinical S. pyogenes isolates with accompanying mutations in the active site of the penicillin binding protein PBP2x, raising concerns that ß-lactam resistance will become more widespread. We screened a global database of S. pyogenes genome sequences to investigate the frequency of PBP mutations, identifying that PBP mutations are uncommon relative to those of Streptococcus pneumoniae These findings support clinical observations that ß-lactam resistance is rare in S. pyogenes and suggest that there are considerable constraints on S. pyogenes PBP sequence variation.
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Proteínas de Bactérias/genética , Variação Genética , Mutação , Proteínas de Ligação às Penicilinas/genética , Streptococcus pyogenes/genética , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Streptococcus pyogenes/efeitos dos fármacosRESUMO
OBJECTIVE: The incidence of heart attack and stroke undergo diurnal variation. Molecular clocks have been described in the heart and the vasculature; however it is largely unknown how the suprachiasmatic nucleus (SCN) entrains these peripheral oscillators. METHODS AND RESULTS: Norepinephrine and epinephrine, added to aortic smooth muscle cells (ASMCs) in vitro, altered Per1, E4bp4, and dbp expression and altered the observed oscillations in clock gene expression. However, oscillations of Per1, E4bp4, dbp, and Per2 were preserved ex vivo in the aorta, heart, and liver harvested from dopamine beta-hydroxylase knockout mice (Dbh-/-) that cannot synthesize either norepinephrine or epinephrine. Furthermore, clock gene oscillations in heart, liver, and white adipose tissue phase shifted identically in Dbh-/- mice and in Dbh+/- controls in response to daytime restriction of feeding. Oscillation of clock genes was similarly preserved ex vivo in tissues from Dbh+/- and Dbh-/- chronically treated with both propranolol and terazosin, thus excluding compensation by dopamine in Dbh-/- mice. CONCLUSIONS: Although adrenergic signaling can influence circadian timing in vitro, peripheral circadian rhythmicity is retained despite its ablation in vivo.
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Proteínas de Ciclo Celular/fisiologia , Ritmo Circadiano/fisiologia , Hepatócitos/fisiologia , Miócitos Cardíacos/fisiologia , Miócitos de Músculo Liso/fisiologia , Animais , Aorta/citologia , Proteínas de Ciclo Celular/genética , Células Cultivadas/fisiologia , Ritmo Circadiano/genética , Dopamina beta-Hidroxilase/genética , Epinefrina/fisiologia , Feminino , Regulação da Expressão Gênica/fisiologia , Humanos , Masculino , Camundongos , Camundongos Knockout , Norepinefrina/fisiologia , Transdução de Sinais/fisiologiaRESUMO
Exercise and cardiac rehabilitation have been underused therapy options for patients with congestive heart failure despite being recommended in international guidelines and being covered by Medicare in the US. This article reviews the evidence behind this treatment strategy and details current trials that will contribute to the evidence base.
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Research in care homes has demonstrated that medication management practices in patients with dysphagia and those receiving medicines covertly may be inappropriate, illegal, and potentially cause harm. This paper presents the results of a feasibility study piloting a resident and healthcare professional best practice charter to improve such practices in care home residents with dysphagia. A charter was developed through a multi-professional expert panel, implemented in one care home, and then piloted in 22 homes in England, Wales, and Northern Ireland. A website was setup and developed iteratively to support the process. Care home staff and residents provided initial feedback on the implementation process and on perceived outcomes six months post implementation. A total of 16 (88.9%) out of 18 respondents from nine homes for six months reported a positive response to the charter. More than 80% of responses regarding the implementation process, impact on staff confidence, and perceived usefulness of the charter were positive. Perceived effectiveness and usefulness could, however, be further improved especially the perceived effect on frequency of medication review, which is reliant on external stakeholder involvement. The charter and supporting website were well received with respondents believing that it was useful, staff showing more confidence, and residents having enhanced care. Approaches to enhancing the charter's effectiveness were identified.
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OPINION STATEMENT: Advances in medical therapy and non-surgical percutaneous options to manage the specter of acute aortic syndromes have improved both patient morbidity and mortality. There are key features in the patient history and initial exam which physicians should be attuned to in order to diagnose acute aortic syndromes such as aortic dissection, penetrating aortic ulcer, and intramural hematoma. Once recognized, early initiation of the appropriate pharmacologic therapy is important, and further appreciating the limitations of such therapy before considering a surgical approach is critical to improve patient outcomes. For the undifferentiated patient with acute aortic dissection presenting to facilities who do not routinely manage this condition, adding pharmacologic agents in the correct sequence assures the best chance for a satisfactory outcome.
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A novel candidate species of the liberibacter genus, 'Candidatus Liberibacter brunswickensis' (CLbr), was identified in the Australian eggplant psyllid, Acizzia solanicola. This is the first discovery of a species belonging to the liberibacter genus in Australia and the first report of a liberibacter species in the psyllid genus Acizzia. This new candidate liberibacter species has not been associated with plant disease, unlike other psyllid-vectored species in the genus including 'Candidatus Liberibacter asiaticus' (CLas), 'Candidatus Liberibacter africanus' (CLaf) and 'Ca. Liberibacter solanacearum' (CLso). This study describes novel generic liberibacter genus primers, used to screen Australian psyllids for the presence of microflora that may confound diagnosis of exotic pathogens. CLbr forms a unique clade in the liberibacter genus based on phylogenetic analysis of the 16S ribosomal ribonucleic acid (rRNA) region and multilocus sequence analysis (MLSA) of seven highly conserved genes, dnaG, gyrB, mutS, nusG, rplA, rpoB and tufB. The MLSA mapping approach described in this article was able to discriminate between two 'Ca. Liberibacter' species within a metagenomic data set and represents a novel approach to detecting and differentiating unculturable species of liberibacter. Further, CLbr can confound the Li et al. (2006) quantitative PCR (qPCR) diagnostic tests for CLas and CLaf.
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Hemípteros/microbiologia , Rhizobiaceae/classificação , Rhizobiaceae/isolamento & purificação , Animais , Austrália , Proteínas de Bactérias/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Metagenômica , Tipagem de Sequências Multilocus , Filogenia , RNA Ribossômico 16S/genética , Rhizobiaceae/genética , Solanum melongena/parasitologiaRESUMO
A number of mitochondrial diseases arise from single-nucleotide variant (SNV) accumulation in multiple mitochondria. Here, we present a method for identification of variants present at the single-mitochondrion level in individual mouse and human neuronal cells, allowing for extremely high-resolution study of mitochondrial mutation dynamics. We identified extensive heteroplasmy between individual mitochondrion, along with three high-confidence variants in mouse and one in human that were present in multiple mitochondria across cells. The pattern of variation revealed by single-mitochondrion data shows surprisingly pervasive levels of heteroplasmy in inbred mice. Distribution of SNV loci suggests inheritance of variants across generations, resulting in Poisson jackpot lines with large SNV load. Comparison of human and mouse variants suggests that the two species might employ distinct modes of somatic segregation. Single-mitochondrion resolution revealed mitochondria mutational dynamics that we hypothesize to affect risk probabilities for mutations reaching disease thresholds.