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1.
Genome Biol ; 25(1): 40, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38297316

RESUMO

BACKGROUND: Pervasive usage of alternative promoters leads to the deregulation of gene expression in carcinogenesis and may drive the emergence of new genes in spermatogenesis. However, little is known regarding the mechanisms underpinning the activation of alternative promoters. RESULTS: Here we describe how alternative cancer-testis-specific transcription is activated. We show that intergenic and intronic CTCF binding sites, which are transcriptionally inert in normal somatic cells, could be epigenetically reprogrammed into active de novo promoters in germ and cancer cells. BORIS/CTCFL, the testis-specific paralog of the ubiquitously expressed CTCF, triggers the epigenetic reprogramming of CTCF sites into units of active transcription. BORIS binding initiates the recruitment of the chromatin remodeling factor, SRCAP, followed by the replacement of H2A histone with H2A.Z, resulting in a more relaxed chromatin state in the nucleosomes flanking the CTCF binding sites. The relaxation of chromatin around CTCF binding sites facilitates the recruitment of multiple additional transcription factors, thereby activating transcription from a given binding site. We demonstrate that the epigenetically reprogrammed CTCF binding sites can drive the expression of cancer-testis genes, long noncoding RNAs, retro-pseudogenes, and dormant transposable elements. CONCLUSIONS: Thus, BORIS functions as a transcription factor that epigenetically reprograms clustered CTCF binding sites into transcriptional start sites, promoting transcription from alternative promoters in both germ cells and cancer cells.


Assuntos
Proteínas de Ligação a DNA , Fatores de Transcrição , Masculino , Humanos , Proteínas de Ligação a DNA/metabolismo , Fator de Ligação a CCCTC/metabolismo , Fatores de Transcrição/metabolismo , Histonas/metabolismo , Cromatina , Sítios de Ligação
3.
Br J Dermatol ; 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37874770

RESUMO

BACKGROUND: Merkel Cell Carcinoma (MCC) is a rare, aggressive skin cancer that most commonly occurs in UV-exposed body sites. Its epidemiology in different geographies and populations is not well characterised. OBJECTIVE: The objective of this systematic review is to summarize evidence on the incidence, mortality, and survival rates of MCC from population-based studies. METHODS: We searched MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials from database inception to June 6th, 2023. No geographic, age or date exclusions were applied. We included population-based studies of MCC that reported the incidence, survival, or mortality rate, and considered systematic reviews. A data-charting form was created and validated to identify variables to extract. Two reviewers then independently charted the data for each included study with patient characteristics, and estimates of incidence rate, mortality rate, and survival rate and assessed the quality of included studies using the Joanna Briggs Institute Checklist for Prevalence studies, Newcastle-Ottawa Scale and Assessment of Multiple Systematic Reviews. We abstracted age-, sex-, stage- and race-stratified outcomes, and synthesized comparisons between strata narratively and using vote counting. We assessed the certainty of evidence for those comparisons using the Grading of Recommendations, Assessments, Developments and Evaluations framework. RESULTS: We identified 11,472 citations, of which 52 studies from 24 countries met our inclusion criteria. Stage 1 and the head and neck were the most frequently reported stage and location at diagnosis. The incidence of MCC is increasing over time (high certainty), with the highest reported incidences reported in Southern hemisphere countries (Australia [2.5 per 100,000], New Zealand [0.96 per 100,000]) (high certainty). Male patients generally had higher incidence rates compared to female patients (high certainty), although there were some variations over time periods. Survival rates varied, with lower survival and/or higher mortality associated with male sex (moderate certainty), higher stage at diagnosis (moderate-to-high certainty), older age (moderate certainty), and immunosuppression (low-to-moderate certainty). CONCLUSIONS: MCC is increasing in incidence and may increase further given the ageing population of many countries. The prognosis of MCC is poor, particularly for males, those who are immunosuppressed, and patients diagnosed at higher stages or at an older age.

4.
Front Mol Neurosci ; 16: 1185796, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324587

RESUMO

Introduction: CTCF-related disorder (CRD) is a neurodevelopmental disorder (NDD) caused by monoallelic pathogenic variants in CTCF. The first CTCF variants in CRD cases were documented in 2013. To date, 76 CTCF variants have been further described in the literature. In recent years, due to the increased application of next-generation sequencing (NGS), growing numbers of CTCF variants are being identified, and multiple genotype-phenotype databases cataloging such variants are emerging. Methods: In this study, we aimed to expand the genotypic spectrum of CRD, by cataloging NDD phenotypes associated with reported CTCF variants. Here, we systematically reviewed all known CTCF variants reported in case studies and large-scale exome sequencing cohorts. We also conducted a meta-analysis using public variant data from genotype-phenotype databases to identify additional CTCF variants, which we then curated and annotated. Results: From this combined approach, we report an additional 86 CTCF variants associated with NDD phenotypes that have not yet been described in the literature. Furthermore, we describe and explain inconsistencies in the quality of reported variants, which impairs the reuse of data for research of NDDs and other pathologies. Discussion: From this integrated analysis, we provide a comprehensive and annotated catalog of all currently known CTCF mutations associated with NDD phenotypes, to aid diagnostic applications, as well as translational and basic research.

5.
Hand (N Y) ; 18(6): 999-1004, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-35193427

RESUMO

BACKGROUND: The COVID-19 pandemic caused significant morbidity and mortality in people who inject drugs (PWID). Upper extremity soft tissue infections are frequently associated with intravenous drug use (IVDU) due to poor compliance with aseptic technique. In Canada, multiple safe injection sites providing clean injection supplies closed, leaving many PWID with no alternatives to inject safely. It was hypothesized that these closures will correspond with increased morbidity and mortality among PWID. The main objective of this study was to determine the effect of the COVID-19 pandemic on the incidence of upper extremity infections in PWID. METHODS: This was a retrospective chart review study. The primary outcome of interest was the frequency of upper extremity infections in PWID. Data were filtered to include only those patients presenting to the emergency department between March to June of 2019 and 2020. Chi-squared analysis was used to compare the number of IVDU patients among patients with upper extremity skin infections between these time periods. RESULTS: The number of IVDU patients treated for upper extremity infections in Hamilton significantly increased during the pandemic, relative risk = 2.0 (95% confidence interval [CI]: 1.3-2.9, P = .0012,) while total upper extremity infections numbers have decreased overall. During the pandemic, PWID made up a larger proportion of upper extremity infections (χ2 = 10.444, P = .00123). Demographic data such as age and sex of IVDU patients presenting with upper extremity infection was not significantly affected by the pandemic. CONCLUSIONS: The effect of the pandemic on accessing harm reduction services has led to evident increases in morbidity as described by this study. Further research on the impact of closures in PWID is needed to quantify these harms and work toward mitigation strategies.


Assuntos
COVID-19 , Abuso de Substâncias por Via Intravenosa , Humanos , Abuso de Substâncias por Via Intravenosa/complicações , Abuso de Substâncias por Via Intravenosa/epidemiologia , Pandemias , Estudos Retrospectivos , COVID-19/epidemiologia , COVID-19/complicações , Controle de Doenças Transmissíveis , Extremidade Superior
6.
Equine Vet J ; 55(4): 573-583, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36199162

RESUMO

Clinical predictive models use a patient's baseline demographic and clinical data to make predictions about patient outcomes and have the potential to aid clinical decision making. The extent of equine clinical predictive models is unknown in the literature. Using PubMed and Google Scholar, we systematically reviewed the predictive models currently described for use in equine patients. Models were eligible for inclusion if they were published in a peer-reviewed article as a multivariable model used to predict a clinical/laboratory/imaging outcome in an individual horse or herd. The agreement of at least two authors was required for model inclusion. We summarised the patient populations, model development methods, performance metric reporting, validation efforts, and, using the Predictive model Risk of Bias Assessment Tool (PROBAST), assessed the risk of bias and applicability concerns for these models. In addition, we summarised the index conditions for which models were developed and provided detailed information on included models. A total of 90 predictive models and 9 external validation studies were included in the final systematic review. A plurality of models (41%) was developed to predict outcomes associated with colic, for example, need for surgery or survival to discharge. All included models were at high risk of bias, defined as failing one or more PROBAST signalling questions, primarily for analysis-related reasons. Importantly, a high risk of bias does not necessarily mean that models are unusable, but that they require more careful consideration prior to clinical use. Concerns about applicability were low for the majority of models. Systematic reviews such as this can serve to increase veterinarians' awareness of predictive models, including evaluation of their performance and their use in different patient populations.


Assuntos
Prognóstico , Cavalos , Animais , Viés
7.
Langmuir ; 38(44): 13506-13521, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36279502

RESUMO

Self-assembled monolayers (SAMs) of organic molecules on metal surfaces are a type of inexpensive surface coating often used to improve metal substrate properties for sensors, electrochemistry, and nanofabrication applications. Iron, specifically, is one of the most commonly used metals, both as a pure metal and as an alloy due to its high conductivity, strong ferromagnetism, and low cost. However, magnetorheological fluids, which have shown impressive energy dampening in fields from civil infrastructure to biomedical devices utilizing iron dispersions, have suffered from low reliability and efficiency due to iron particle oxidation, corrosion, and settling. To understand the effect of self-assembled monolayers on iron and both the adsorbed particle's resistance against aggregation and performance impact, this work performs an in-depth study on alkanethiol-based self-assembled monolayers on iron particles. Adsorption of alkanethiols and the generation of SAMs on micron-sized iron particles were evaluated as a function of adsorption solvent polarity and alkanethiol chain length. Maximum alkanethiol loading, determined from appropriate isotherms, was found to strongly be a function of both parameters. Alkanethiol adsorption increased with increasing alkyl chain length and increasing solvent log P values in polar solvents. With respect to magnetorheologically relevant parameters, alkanethiol adsorption did not show any significant effect on both the magnetic properties of iron (as particles) and fluid on-state yield stress. The colloidal stability of n-alkanethiol adsorbed iron-based magnetorheological fluids (MRFs) was a function of both n-alkanethiol chain length and the iron particle adsorption solvent. MRFs composed of hexadecanethiol adsorbed iron prepared in polar solvents like methanol and ethanol showed excellent sedimentation stability compared to all other MRFs prepared in this study.

8.
BMC Med Ethics ; 23(1): 73, 2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35836232

RESUMO

BACKGROUND: Junior medical doctors have a key role in discussions and decisions about treatment and end-of-life care for people with dementia in hospital. Little is known about junior doctors' decision-making processes when treating people with dementia who have advance care directives (ACDs), or the factors that influence their decisions. To describe among junior doctors in relation to two hypothetical vignettes involving patients with dementia: (1) their legal compliance and decision-making process related to treatment decisions; (2) the factors influencing their clinical decision-making; and (3) the factors associated with accurate responses to one hypothetical vignette. METHOD: A cross-sectional survey of junior doctors, including trainees, interns, registrars and residents, on clinical rotation in five public hospitals located in one Australian state. The anonymous, investigator-developed survey was conducted between August 2018 and June 2019. Two hypothetical vignettes describing patients with dementia presenting to hospital with an ACD and either: (1) bacterial pneumonia; or (2) suspected stroke were presented in the survey. Participants were asked to indicate whether they would commence treatment, given the ACD instructions described in each vignette. RESULTS: Overall, 116 junior doctors responded (35% consent rate). In Vignette 1, 58% of respondents (n = 67/116) selected the legally compliant option (i.e. not commence treatment). Participants who chose the legally compliant option perceived 'following patient wishes' (n = 32/67; 48%) and 'legal requirements to follow ACDs' (n = 32/67; 48%) as equally important reasons for complying with the ACD. The most common reason for not selecting the legally compliant option in Vignette 1 was the 'ACD is relevant in my decision-making process, but other factors are more relevant' (n = 14/37; 38%). In Vignette 2, 72% of respondents (n = 83/116) indicated they would commence treatment (i.e. not follow the ACD) and 18% (n = 21/116) selected they would not commence treatment. (i.e. follow the ACD). Similar reasons influenced participant decision-making in Vignette 2, a less legally certain scenario. CONCLUSIONS: There are critical gaps in junior doctors' compliance with the law as it relates to the implementation of ACDs. Despite there being differences in relation to the legal answer and its certainty, clinical and ethical factors guided decision-making over and above the law in both vignettes. More education and training to guide junior doctors' clinical decision-making and ensure compliance with the law is required.


Assuntos
Demência , Médicos , Austrália , Estudos Transversais , Tomada de Decisões , Demência/terapia , Humanos
9.
BMC Med Ethics ; 23(1): 74, 2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35850728

RESUMO

BACKGROUND: For the benefits of advance care planning to be realised during a hospital admission, the treating team must have accurate knowledge of the law pertaining to implementation of advance care directives (ACDs) and substitute decision making. AIMS: To determine in a sample of Junior Medical Officers (JMOs): (1) knowledge of the correct order to approach people as substitute decision makers if a patient does not have capacity to consent to treatment; (2) knowledge of the legal validity of ACDs when making healthcare decisions for persons without capacity to consent to treatment, including the characteristics associated with higher knowledge; and (3) barriers to enacting ACDs. METHODS: A cross-sectional survey was conducted at five public hospitals in New South Wales, Australia. Interns, residents, registrars, and trainees on clinical rotation during the recruitment period were eligible to participate. Consenting participants completed an anonymous pen-and-paper survey. RESULTS: A total of 118 JMOs completed a survey (36% return rate). Fifty-five percent of participants were female and 56.8% were aged 20-29 years. Seventy-five percent of JMOs correctly identified a Guardian as the first person to approach if a patient did not have decision-making capacity, and 74% correctly identified a person's spouse or partner as the next person to approach. Only 16.5% identified all four persons in the correct order, and 13.5% did not identify any in the correct order. The mean number of correct responses to the questions assessing knowledge of the legal validity of ACDs was 2.6 (SD = 1.1) out of a possible score of 6. Only 28 participants (23.7%) correctly answered four or more knowledge statements correctly. None of the explored variables were significantly associated with higher knowledge of the legal validity of ACDs. Uncertainty about the currency of ACDs and uncertainty about the legal implications of relying on an ACD when a patient's family or substitute decision maker disagree with it were the main barriers to enacting ACDs. CONCLUSION: JMOs knowledge of the legal validity of ACDs for persons without decision making capacity and the substitute decision making hierarchy is limited. There is a clear need for targeted education and training to improve knowledge in this area for this cohort.


Assuntos
Planejamento Antecipado de Cuidados , Diretivas Antecipadas , Estudos Transversais , Tomada de Decisões , Feminino , Pessoal de Saúde , Humanos , Masculino
10.
SAGE Open Med Case Rep ; 9: 2050313X20984119, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33889411

RESUMO

We represent a pediatric case of the congenital disorder caused by zinc malabsorption, acrodermatitis enteropathica, presenting with acute onsetof blisters. Although blisters can be seen in this condition, it is not always a key feature and can therefore be overlooked when considering a differential diagnosis of acute blistering in infancy. We therefore review the common and less common features of this cutaneous eruption as well as provide an extensive differential diagnosis for acute blistering in infancy. We also emphasize the importance of lifelong treatment with zinc supplementation in these children.

11.
Int J Mol Sci ; 22(4)2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33671852

RESUMO

SINE-VNTR-Alu (SVA) retrotransposons are a subclass of transposable elements (TEs) that exist only in primate genomes. TE insertions can be co-opted as cis-regulatory elements (CREs); however, the regulatory potential of SVAs has predominantly been demonstrated using bioinformatic approaches and reporter gene assays. The objective of this study was to demonstrate SVA cis-regulatory activity by CRISPR (clustered regularly interspaced short palindromic repeats) deletion and subsequent measurement of direct effects on local gene expression. We identified a region on chromosome 17 that was enriched with human-specific SVAs. Comparative gene expression analysis at this region revealed co-expression of TRPV1 and TRPV3 in multiple human tissues, which was not observed in mouse, highlighting key regulatory differences between the two species. Furthermore, the intergenic region between TRPV1 and TRPV3 coding sequences contained a human specific SVA insertion located upstream of the TRPV3 promoter and downstream of the 3' end of TRPV1, highlighting this SVA as a candidate to study its potential cis-regulatory activity on both genes. Firstly, we generated SVA reporter gene constructs and demonstrated their transcriptional regulatory activity in HEK293 cells. We then devised a dual-targeting CRISPR strategy to facilitate the deletion of this entire SVA sequence and generated edited HEK293 clonal cell lines containing homozygous and heterozygous SVA deletions. In edited homozygous ∆SVA clones, we observed a significant decrease in both TRPV1 and TRPV3 mRNA expression, compared to unedited HEK293. In addition, we also observed an increase in the variability of mRNA expression levels in heterozygous ∆SVA clones. Overall, in edited HEK293 with SVA deletions, we observed a disruption to the co-expression of TRPV1 and TRPV3. Here we provide an example of a human specific SVA with cis-regulatory activity in situ, supporting the role of SVA retrotransposons as contributors to species-specific gene expression.


Assuntos
Elementos Alu/genética , Sistemas CRISPR-Cas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , DNA Intergênico/genética , Repetições Minissatélites/genética , Regiões Promotoras Genéticas/genética , Elementos Nucleotídeos Curtos e Dispersos/genética , Canais de Cátion TRPV/genética , Animais , Expressão Gênica , Regulação da Expressão Gênica , Genes Reporter , Células HEK293 , Humanos , Camundongos , Primatas/genética
12.
Intern Med J ; 51(12): 2055-2060, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32687240

RESUMO

BACKGROUND: A resuscitation plan is a medically authorised order to use or withhold resuscitation interventions. Absence of appropriate resuscitation orders exposes patients to the risk of invasive medical interventions that may be of questionable benefit depending on individual circumstances. AIMS: To describe among junior doctors: (i) self-reported confidence discussing and completing resuscitation plans; (ii) knowledge of resuscitation policy including whether resuscitation plans are legally enforceable and key triggers for completion; and (iii) the factors associated with higher knowledge of triggers for completing resuscitation plans. METHODS: A cross-sectional survey was conducted at five hospitals. Junior doctors on clinical rotation were approached at scheduled training sessions, before or after ward rounds or at change of rotation orientation days and provided with a pen-and-paper survey. RESULTS: A total of 118 junior doctors participated. Most felt confident discussing (79%; n = 92) and documenting (87%; n = 102) resuscitation plans with patients. However, only 45% (n = 52) of doctors correctly identified that resuscitation plans are legally enforceable medical orders. On average, doctors correctly identified 6.8 (standard deviation = 1.8) out of 10 triggers for completing a resuscitation plan. Doctors aged >30 years were four times more likely to have high knowledge of triggers for completing resuscitation plans (odds ratio 4.28 (95% confidence interval 1.54-11.89); P = 0.0053). CONCLUSION: Most junior doctors feel confident discussing and documenting resuscitation plans. There is a need to improve knowledge about legal obligations to follow completed resuscitation plans, and about when resuscitation plans should be completed to ensure they are completed with patients who are most at risk.


Assuntos
Corpo Clínico Hospitalar , Médicos , Adulto , Estudos Transversais , Humanos , Corpo Clínico Hospitalar/educação , Ordens quanto à Conduta (Ética Médica) , Inquéritos e Questionários
13.
J Am Acad Dermatol ; 85(2): 353-359, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32289389

RESUMO

BACKGROUND: Early detection of melanoma is crucial to improving the detection of thin curable melanomas. Noninvasive, computer-assisted methods have been developed to use at the bedside to aid in diagnoses but have not been compared directly in a clinical setting. OBJECTIVE: We conducted a prospective diagnostic accuracy study comparing a dermatologist's clinical examination at the bedside, teledermatology, and noninvasive imaging techniques (FotoFinder, MelaFind, and Verisante Aura). METHODS: A total of 184 patients were recruited prospectively from an outpatient dermatology clinic, with lesions imaged, assessed, and excised. Skin specimens were assessed by 2 blinded pathologists, providing the gold standard comparison. RESULTS: Fifty-nine lesions from 56 patients had a histopathologic diagnosis of melanoma, whereas 150 lesions from 128 patients were diagnosed as benign. Sensitivities and specificities were, respectively, MelaFind (82.5%, 52.4%), Verisante Aura (21.4%, 86.2%), and FotoFinder Moleanalyzer Pro (88.1%, 78.8%). The sensitivity and specificity of the teledermoscopist (84.5% and 82.6%, respectively) and local dermatologist (96.6% and 32.2%, respectively) were also compared. LIMITATIONS: There are inherent limitations in using pathology as the gold standard to compare sensitivities and specificities. CONCLUSION: This study demonstrates that the highest sensitivity and specificity of the instruments were established with the FotoFinder Moleanalyzer Pro, which could be a valuable tool to assist with, but not replace, clinical decision making.


Assuntos
Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico por imagem , Feminino , Humanos , Masculino , Melanoma/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Kidney Med ; 2(4): 388-397, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32775978

RESUMO

RATIONALE & OBJECTIVE: More than 50% of hemodialysis patients experience sleep disturbance and most have coexisting sleep apnea. However, how sleep apnea affects sleep and the overall experience of patients with chronic kidney disease treated by hemodialysis has not been evaluated. STUDY DESIGN: A mixed-methods design, incorporating cross-sectional observational and descriptive qualitative methodologies. SETTING & PARTICIPANTS: Patients receiving maintenance hemodialysis in Newcastle, New South Wales, Australia, with newly diagnosed sleep apnea (apnea-hypopnea index ≥ 5 per hour). ASSESSMENTS: In-laboratory polysomnography to assess sleep apnea and objective sleep parameters. Epworth Sleepiness Scale to assess daytime symptoms. A semi-structured qualitative interview to explore patient experience. ANALYTICAL APPROACH: Descriptive and iterative thematic analysis. RESULTS: We analyzed 36 patients with newly diagnosed sleep apnea and interviewed 26 (mean age, 62 years, median apnea-hypopnea index, 32 per hour). Severity of sleep apnea did not affect patients' sleep duration, sleep efficiency, or self-reported Epworth Sleepiness Scale score. From the qualitative interviews, 4 themes emerged: "broken sleep" related to short sleep duration, with waking and dozing off a common sleep cycle, caused by uncontrolled pain and dialysis. Many participants reported regularly "feeling unrefreshed" on waking. "Impact of sleep disturbance" included reduced physical, mental, and self-management capacity. Finally, interviewees described the need to use strategies to "soldier on" with symptoms. LIMITATIONS: Participants' views are only transferrable to hemodialysis patients with sleep apnea. CONCLUSIONS: Our findings suggest that severity of sleep apnea does not affect sleep time or patient-reported daytime sleepiness; however, hemodialysis patients with sleep apnea report disturbed and unrefreshed sleep and the debilitating effects of sleep disturbance is profound. Broken and unrefreshed sleep were the dominant symptoms of sleep apnea and should be assessed routinely to identify patients with sleep apnea and improve quality of life in patients with chronic kidney disease treated with hemodialysis.

15.
J Virol ; 94(13)2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32321802

RESUMO

Influenza A virus (IAV) increases the presentation of class I human leukocyte antigen (HLA) proteins that limit antiviral responses mediated by natural killer (NK) cells, but molecular mechanisms for these processes have not yet been fully elucidated. We observed that infection with A/Fort Monmouth/1/1947(H1N1) IAV significantly increased the presentation of HLA-B, -C, and -E on lung epithelial cells. Virus entry was not sufficient to induce HLA upregulation because UV-inactivated virus had no effect. Aberrant internally deleted viral RNAs (vRNAs) known as mini viral RNAs (mvRNAs) and defective interfering RNAs (DI RNAs) expressed from an IAV minireplicon were sufficient for inducing HLA upregulation. These defective RNAs bind to retinoic acid-inducible gene I (RIG-I) and initiate mitochondrial antiviral signaling (MAVS) protein-dependent antiviral interferon (IFN) responses. Indeed, MAVS was required for HLA upregulation in response to IAV infection or ectopic mvRNA/DI RNA expression. The effect was partially due to paracrine signaling, as we observed that IAV infection or mvRNA/DI RNA-expression stimulated production of IFN-ß and IFN-λ1 and conditioned media from these cells elicited a modest increase in HLA surface levels in naive epithelial cells. HLA upregulation in response to aberrant viral RNAs could be prevented by the Janus kinase (JAK) inhibitor ruxolitinib. While HLA upregulation would seem to be advantageous to the virus, it is kept in check by the viral nonstructural 1 (NS1) protein; we determined that NS1 limits cell-intrinsic and paracrine mechanisms of HLA upregulation. Taken together, our findings indicate that aberrant IAV RNAs stimulate HLA presentation, which may aid viral evasion of innate immunity.IMPORTANCE Human leukocyte antigens (HLAs) are cell surface proteins that regulate innate and adaptive immune responses to viral infection by engaging with receptors on immune cells. Many viruses have evolved ways to evade host immune responses by modulating HLA expression and/or processing. Here, we provide evidence that aberrant RNA products of influenza virus genome replication can trigger retinoic acid-inducible gene I (RIG-I)/mitochondrial antiviral signaling (MAVS)-dependent remodeling of the cell surface, increasing surface presentation of HLA proteins known to inhibit the activation of an immune cell known as a natural killer (NK) cell. While this HLA upregulation would seem to be advantageous to the virus, it is kept in check by the viral nonstructural 1 (NS1) protein, which limits RIG-I activation and interferon production by the infected cell.


Assuntos
Genes MHC Classe I/genética , Antígenos HLA/metabolismo , Vírus da Influenza A Subtipo H1N1/genética , Células A549 , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteína DEAD-box 58/genética , Bases de Dados Genéticas , Células Epiteliais/virologia , Interações Hospedeiro-Patógeno/genética , Humanos , Imunidade Inata , Vírus da Influenza A/genética , Influenza Humana/genética , Células Matadoras Naturais/metabolismo , Pulmão/virologia , RNA Viral/genética , Transdução de Sinais , Ativação Transcricional , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/genética
16.
J Cutan Med Surg ; 24(1): 28-32, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31526046

RESUMO

BACKGROUND: Punctate palmoplantar keratoderma type 1 (PPPK1) presents in late childhood to adulthood with multiple small discrete hyperkeratotic papules on palms and soles. PPPK1 is an autosomal dominant skin disease caused by AAGAB mutations. It has been suggested that PPPK1 may be associated with an increased predisposition to systemic malignancies. OBJECTIVES: To evaluate the presence of AAGAB mutations in Canadian families with PPPK1 and the possible increased predisposition to systemic malignancies. METHODS: Eighteen unrelated Canadian families with PPPK1 were recruited for this study. Genomic DNA was extracted from saliva and PCR amplification was performed for all AAGAB exons and exon/intron junctions. PCR products were sequenced and analyzed for mutations. A family history of malignancy was obtained from the index case and, when possible, from other family members. RESULTS: We have identified 5 heterozygous AAGAB loss of function mutations in 11 families. The mutation c.370 C>T, p.Arg124* was the most prevalent and was identified in 6 families. A splice site mutation, c.451+3delAAGT, was identified in 2 families. The other mutations c.473delG, p.Gly158Glufs*0; c.550-551insAAT, p.Gly183*; and c.505-506 dupAA, p.Asn169Lysfs*6 were each identified in 1 family. Different cancers were reported in 11 families (Table 1 and Supplemental Figure S1). CONCLUSIONS: AAGAB mutations were found in 11 of 18 families with PPPK1. In some families there appears to be an association with cancer.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/genética , DNA/genética , Ceratodermia Palmar e Plantar/genética , Mutação , Neoplasias/etiologia , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Adulto , Canadá/epidemiologia , Análise Mutacional de DNA , Feminino , Humanos , Incidência , Ceratodermia Palmar e Plantar/complicações , Ceratodermia Palmar e Plantar/metabolismo , Masculino , Pessoa de Meia-Idade , Neoplasias/genética , Neoplasias/metabolismo , Linhagem , Adulto Jovem
17.
Cell Rep ; 27(3): 776-792.e7, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30995476

RESUMO

Many viruses shut off host gene expression to inhibit antiviral responses. Viral proteins and host proteins required for viral replication are typically spared in this process, but the mechanisms of target selectivity during host shutoff remain poorly understood. Using transcriptome-wide and targeted reporter experiments, we demonstrate that the influenza A virus endoribonuclease PA-X usurps RNA splicing to selectively target host RNAs for destruction. Proximity-labeling proteomics reveals that PA-X interacts with cellular RNA processing proteins, some of which are partially required for host shutoff. Thus, PA-X taps into host nuclear pre-mRNA processing mechanisms to destroy nascent mRNAs shortly after their synthesis. This mechanism sets PA-X apart from other viral host shutoff proteins that target actively translating mRNAs in the cytoplasm. Our study reveals a unique mechanism of host shutoff that helps us understand how influenza viruses suppress host gene expression.


Assuntos
Vírus da Influenza A/fisiologia , Splicing de RNA , RNA Mensageiro/metabolismo , Proteínas Repressoras/metabolismo , Proteínas não Estruturais Virais/metabolismo , Células A549 , Fator de Especificidade de Clivagem e Poliadenilação/antagonistas & inibidores , Fator de Especificidade de Clivagem e Poliadenilação/genética , Fator de Especificidade de Clivagem e Poliadenilação/metabolismo , Regulação para Baixo , Endorribonucleases/metabolismo , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Interferons/genética , Interferons/metabolismo , Mutagênese Sítio-Dirigida , Interferência de RNA , Precursores de RNA/metabolismo , Sítios de Splice de RNA , RNA Interferente Pequeno/metabolismo , Proteínas Repressoras/genética , Regulação para Cima , Proteínas não Estruturais Virais/genética , Fatores de Poliadenilação e Clivagem de mRNA/antagonistas & inibidores , Fatores de Poliadenilação e Clivagem de mRNA/genética , Fatores de Poliadenilação e Clivagem de mRNA/metabolismo
18.
Free Radic Biol Med ; 131: 197-208, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30529384

RESUMO

Inadequate delivery of oxygen to organisms during development can lead to cell dysfunction/death and life-long disabilities. Although the susceptibility of developing cells to low oxygen conditions changes with maturation, the cellular and molecular pathways that govern responses to low oxygen are incompletely understood. Here we show that developing Caenorhabditis elegans are substantially more sensitive to anoxia than adult animals and that this sensitivity is controlled by nervous system generated hormones (e.g., neuropeptides). A screen of neuropeptide genes identified and validated nlp-40 and its receptor aex-2 as a key regulator of anoxic survival in developing worms. The survival-promoting action of impaired neuropeptide signaling does not rely on five known stress resistance pathways and is specific to anoxic insult. Together, these data highlight a novel cell non-autonomous pathway that regulates the susceptibility of developing organisms to anoxia.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Regulação da Expressão Gênica no Desenvolvimento , Hipóxia/genética , Longevidade/genética , Neuropeptídeos/genética , Receptores Acoplados a Proteínas G/genética , Animais , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Perfilação da Expressão Gênica , Hipóxia/metabolismo , Neuropeptídeos/metabolismo , Oxigênio/metabolismo , Pró-Proteína Convertase 2/genética , Pró-Proteína Convertase 2/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais
19.
Eat Behav ; 8(1): 65-72, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17174853

RESUMO

OBJECTIVE: The current study aimed to investigate the difference in the levels of core beliefs between eating disordered women and those who showed milder forms of symptomatology. METHODS: Thirty-five eating disordered women, 16 symptomatic dieters, 39 normal dieters and 34 non-clinical comparison women completed questionnaires measuring eating symptomatology (Eating Disorders Inventory [EDI]), core beliefs (Young Schema Questionnaire [YSQ]), depression (The Beck Depression Inventory-II [BDI-II]) and self-esteem (Rosenberg Self-Esteem Inventory [RSE]). RESULTS: With the exception of Entitlement beliefs, there were significant differences in the levels of core beliefs across all four groups. In particular, symptomatic dieters and eating disordered women differed on 8 YSQ subscales despite showing very similar level of eating symptomatology. DISCUSSION: The current findings lend support to the discontinuity model that suggests that there are fundamental differences between women with a clinical eating disorder and those with milder eating psychopathology. The clinical and research implications of the present results were discussed.


Assuntos
Anorexia Nervosa/psicologia , Bulimia Nervosa/psicologia , Cultura , Dieta Redutora/psicologia , Adolescente , Adulto , Anorexia Nervosa/diagnóstico , Imagem Corporal , Índice de Massa Corporal , Bulimia Nervosa/diagnóstico , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/psicologia , Feminino , Humanos , Inventário de Personalidade , Autoimagem , Inquéritos e Questionários
20.
Optom Vis Sci ; 80(6): 460-6, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12808407

RESUMO

PURPOSE: The hypotensive effect of exercise on intraocular pressure is well documented, however, little is known about the effect of exercise on pulsatile ocular blood flow. This study examines this effect and follows the recovery of intraocular pressure and pulsatile ocular blood flow after a standard exercise period. METHODS: Eighteen visually normal subjects participated in a 4-min period of bicycle ergometry. Intraocular pressure and pulsatile ocular blood flow were measured by pneumotonometry before, immediately after exercise, and at regular intervals during the recovery period. RESULTS: Intraocular pressure was found to decrease significantly with strenuous exercise and recovered gradually toward baseline over a period of 30 min. Pulsatile ocular blood flow increased significantly immediately after exercise then returned to baseline levels between 5 and 10 min after stopping exercise. CONCLUSIONS: This study confirms the hypotensive effect of exercise on intraocular pressure and shows that exercise significantly increases pulsatile ocular blood flow.


Assuntos
Exercício Físico/fisiologia , Olho/irrigação sanguínea , Pressão Intraocular/fisiologia , Adulto , Pressão Sanguínea , Teste de Esforço , Feminino , Frequência Cardíaca , Humanos , Masculino , Fluxo Pulsátil/fisiologia , Valores de Referência , Fluxo Sanguíneo Regional/fisiologia , Tonometria Ocular
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