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OBJECTIVE: Epigenetic mechanisms, including DNA methylation (DNAm), have been proposed to play a key role in Crohn's disease (CD) pathogenesis. However, the specific cell types and pathways affected as well as their potential impact on disease phenotype and outcome remain unknown. We set out to investigate the role of intestinal epithelial DNAm in CD pathogenesis. DESIGN: We generated 312 intestinal epithelial organoids (IEOs) from mucosal biopsies of 168 patients with CD (n=72), UC (n=23) and healthy controls (n=73). We performed genome-wide molecular profiling including DNAm, bulk as well as single-cell RNA sequencing. Organoids were subjected to gene editing and the functional consequences of DNAm changes evaluated using an organoid-lymphocyte coculture and a nucleotide-binding oligomerisation domain, leucine-rich repeat and CARD domain containing 5 (NLRC5) dextran sulphate sodium (DSS) colitis knock-out mouse model. RESULTS: We identified highly stable, CD-associated loss of DNAm at major histocompatibility complex (MHC) class 1 loci including NLRC5 and cognate gene upregulation. Single-cell RNA sequencing of primary mucosal tissue and IEOs confirmed the role of NLRC5 as transcriptional transactivator in the intestinal epithelium. Increased mucosal MHC-I and NLRC5 expression in adult and paediatric patients with CD was validated in additional cohorts and the functional role of MHC-I highlighted by demonstrating a relative protection from DSS-mediated mucosal inflammation in NLRC5-deficient mice. MHC-I DNAm in IEOs showed a significant correlation with CD disease phenotype and outcomes. Application of machine learning approaches enabled the development of a disease prognostic epigenetic molecular signature. CONCLUSIONS: Our study has identified epigenetically regulated intestinal epithelial MHC-I as a novel mechanism in CD pathogenesis.
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Doença de Crohn , Metilação de DNA , Epigênese Genética , Mucosa Intestinal , Organoides , Humanos , Doença de Crohn/genética , Doença de Crohn/patologia , Doença de Crohn/metabolismo , Organoides/metabolismo , Organoides/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Camundongos , Animais , Feminino , Masculino , Camundongos Knockout , Bancos de Espécimes Biológicos , Adulto , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Modelos Animais de Doenças , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismoRESUMO
PURPOSE: This qualitative study (GSK study: 213635) was designed to better understand sleep disturbance as experienced by individuals with rheumatoid arthritis (RA) or axial spondyloarthritis (axSpA), and the relationship between sleep disturbance and pain and other aspects of the disease and disease activity. METHODS: Sixty-minute, one-on-one, concept elicitation interviews were conducted with 30 participants (15 with RA and 15 with axSpA) from the US. Interviews were audio-recorded and transcribed verbatim. Interview transcripts were coded and analyzed to explore themes related to pain and sleep disturbance, and relationships among those themes. RESULTS: Pain was a prominent driver of sleep disturbance; 12 participants with RA (80%) and 14 with axSpA (93%) reported that pain impacted their ability to fall asleep, while all 15 with RA (100%) and 14 with axSpA (93%) reported that pain impacted their ability to stay asleep. Two-thirds of participants with RA (67%) or axSpA (60%) described a bi-directional relationship, whereby pain worsened sleep disturbance and sleep disturbance further aggravated pain. Factors other than pain, such as fatigue and emotional health, were also reported as important contributors to sleep disturbance (RA: n = 12/15, 80%; axSpA: n = 14/15, 93%). Participants with RA or axSpA described complex interconnections between fatigue, emotional health, pain, and sleep, often labeling these relationships as "vicious cycles". Notably, half of all participants reported sleep disturbance occurring without pain or other understood causes. CONCLUSION: These perspectives collected from people with RA or axSpA suggest that reducing sleep disruption directly may offer clinically relevant benefits.
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Artrite Reumatoide , Espondiloartrite Axial , Transtornos do Sono-Vigília , Espondilite Anquilosante , Humanos , Qualidade de Vida/psicologia , Espondilite Anquilosante/psicologia , Dor , FadigaRESUMO
PURPOSE: A well-defined and reliable patient-reported outcome instrument for COVID-19 is important for assessing symptom severity and supporting research studies. The InFLUenza Patient-Reported Outcome (FLU-PRO) instrument has been expanded to include loss of taste and smell in the FLU-PRO Plus, to comprehensively cover COVID-19 symptoms. Our studies were designed to evaluate and validate the FLU-PRO Plus among patients with COVID-19. METHODS: Two studies were conducted: (1) a qualitative, non-interventional, cross-sectional study of patients with COVID-19 involving hybrid concept elicitation and cognitive debriefing interviews; (2) a psychometric evaluation of the measurement properties of FLU-PRO Plus, using data from COMET-ICE (COVID-19 Monoclonal antibody Efficacy Trial-Intent to Care Early). RESULTS: In the qualitative interviews (n = 30), all 34 items of the FLU-PRO Plus were considered relevant to COVID-19, and participants determined the questionnaire was easily understood, well written, and comprehensive. In the psychometric evaluation (n = 845), the internal consistency reliability of FLU-PRO Plus total score was 0.94, ranging from 0.71 to 0.90 for domain scores. Reproducibility (Day 20-21) was 0.83 for total score, with domain scores of 0.67-0.89. Confirmatory factor analysis with the novel smell/taste domain demonstrated an acceptable fit to the data. CONCLUSION: The content, reliability, validity, and responsiveness of the FLU-PRO Plus in the COVID-19 population were supported. Our results suggest that FLU-PRO Plus is a content- and psychometrically-valid, fit-for-purpose measure which is easily understood by patients. FLU-PRO Plus is a suitable PRO measure for evaluating symptoms of COVID-19 and treatment benefit directly from the patient perspective. TRIAL REGISTRATION: ClinicalTrials.Gov: NCT04545060, September 10, 2020; retrospectively registered.
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COVID-19 , Influenza Humana , Humanos , Reprodutibilidade dos Testes , Psicometria , Estudos Transversais , Qualidade de Vida/psicologia , Medidas de Resultados Relatados pelo Paciente , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Schizophrenia (SZ) and bipolar I disorder (BD-I) are chronic mental health disorders often treated with antipsychotic medications. This qualitative study sought to better understand disease burden and treatment experiences with oral antipsychotic medications in participants living with SZ or BD-I. METHODS: Six 90-min focus groups were conducted with participants diagnosed with SZ or BD-I. Trained moderators facilitated discussions using a semistructured guide. Participants described symptoms, impacts of disease, and experiences with oral antipsychotic medications, whether favourable or unfavourable. RESULTS: Among participants with SZ (n = 15; 3 groups, 5 per group), 53% were male and 33% were white, with a mean of 18.6 years since diagnosis. Of participants with BD-I (n = 24; 3 groups, 8 per group), 33% were male and 42% were white, with a mean of 13.0 years since diagnosis. Participants described numerous symptoms of their illnesses that impacted relationships and daily life, including effects on emotional health, the ability to work, and encounters with law enforcement. Previous antipsychotic medications were deemed effective by 14/15 (93%) participants with SZ and 12/16 (75%) participants with BD-I. Most participants with SZ (13/15; 87%) or with BD-I (16/24; 67%) reported discontinuing their antipsychotic medication at some point. Side effects were a common reason for discontinuing or switching medications for participants with SZ (8/15; 53%) and for those with BD-I (11/24; 46%). The most common side effects reported in both cohorts were weight gain, drowsiness, sexual problems, and neurologic symptoms. Side effects negatively affected quality of life, leading to serious health problems and issues with self-esteem. CONCLUSIONS: People living with SZ or BD-I cited a range of favourable and unfavourable experiences with oral antipsychotic medications. Most participants reported that their antipsychotics were effective at controlling their symptoms, but multiple side effects impacted their quality of life, caused additional serious health problems, and often led to discontinuation of or switching antipsychotics. Findings from this study contribute to a better understanding of patients' experiences with antipsychotics and highlight a need for new medications with favourable benefit/risk profiles.
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Antipsicóticos , Transtorno Bipolar , Esquizofrenia , Humanos , Masculino , Feminino , Esquizofrenia/diagnóstico , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/diagnóstico , Qualidade de Vida , Grupos FocaisRESUMO
BACKGROUND: Patients with sickle cell disease (SCD) experience daily pain and acute episodes known as sickle cell pain crises (SCPCs). The Sickle Cell Pain Diary-Caregiver Report (SCPD-C) is an observer-reported diary for use by caregivers of children ages < 12 years with SCD. This study reports on the content validity of the SCPD-C. METHODS: The SCPD-C was developed based on a literature review, measurement expert input, and a patient advisory board including clinicians. Three rounds of interviews (including both concept elicitation and cognitive debriefing methodologies) were conducted with caregivers of children with SCD aged < 12 to evaluate the content validity of the SCPD-C. RESULTS: Across three rounds of interviews, caregivers confirmed concepts in the SCPD-C and described observed impacts that were important and were added. Overall, caregivers evaluated the SCPD-C as easy to understand, with some minor adaptations for clarity. Additionally, the diary was split into two versions based on the child's age and school enrollment status (SCPD-CS for school-aged and SCPD-CN for non-school age children). CONCLUSIONS: Caregivers provided valuable input that led to important additions and changes to the measures. The SCPD-CS and SCPD-CN are appropriate and fit-for-purpose observer-reported outcome measures of SCPC-related pain frequency and severity, and impacts on health-related quality of life.
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Anemia Falciforme , Cuidadores , Criança , Humanos , Dor , Qualidade de VidaRESUMO
Sebocytes, which are characterized by lipid accumulation that leads to cell disruption, can be found in hair follicle-associated sebaceous glands (SGs) or in free SGs such as the Meibomian glands in the eyelids. Because genetic tools that allow targeting of sebocytes while maintaining intact epidermal lipids are lacking, the relevance of sebaceous lipids in health and disease remains poorly understood. Using Scd3, which is expressed exclusively in mature sebocytes, we established a mouse line with sebocyte-specific expression of Cre recombinase. Both RT-PCR analysis and crossing into Rosa26-lacZ reporter mice and Kras(G12D) mice confirmed Cre activity specifically in SGs, with no activity in other skin compartments. Importantly, loss of SCD3 function did not cause detectable phenotypical alterations, endorsing the usefulness of Scd3-Cre mice for further functional studies. Scd3-Cre-induced, diphtheria chain A toxin-mediated depletion of sebaceous lipids resulted in impaired water repulsion and thermoregulation, increased rates of UVB-induced epidermal apoptosis and caused a severe pathology of the ocular surface resembling Meibomian gland dysfunction. This novel mouse line will be useful for further investigating the roles of sebaceous lipids in skin and eye integrity.
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Apoptose/efeitos da radiação , Olho/efeitos da radiação , Lipídeos/química , Glândulas Sebáceas/química , Raios Ultravioleta , Água/química , Animais , Regulação da Temperatura Corporal/efeitos da radiação , Síndromes do Olho Seco/complicações , Síndromes do Olho Seco/patologia , Homozigoto , Humanos , Inflamação/complicações , Inflamação/patologia , Integrases/metabolismo , Glândulas Tarsais/metabolismo , Glândulas Tarsais/efeitos da radiação , Camundongos Endogâmicos C57BL , Tamanho do Órgão , Especificidade de Órgãos/efeitos da radiação , Fenótipo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Sebo/metabolismoRESUMO
This qualitative, cross-sectional study aimed to understand the barriers and facilitators related to the adherence and completion of the recombinant zoster vaccine (RZV) two-dose series in Canada, as perceived by healthcare providers (HCPs) and patients. Data collection occurred via 60-minute concept elicitation interviews with 12 HCPs (4 physicians, 2 nurse practitioners, 6 pharmacists) who had prescribed and/or administered RZV in Canada, and 21 patients aged ≥50 years who had received ≥1 dose of RZV. Patients were categorized as adherent (received both doses within the recommended 2-to-6-month timeframe; n = 11) or non-adherent (received only one dose or second dose outside the recommended timeframe; n = 10). Interview transcripts were coded and analyzed using a two-part thematic analysis approach. HCP-identified barriers to RZV adherence included high out-of-pocket cost, inconsistent/lack of health plan coverage, inconvenient processes for accessing RZV, and patient forgetfulness. HCP-identified facilitators included desire for shingles protection, HCP encouragement, and reminders. Barriers to RZV adherence identified by patients included lack of HCP knowledge/experience with RZV, receiving unreliable/confusing information, having unpleasant/severe side effects following the first dose, high out-of-pocket cost, lack of insurance coverage, and forgetfulness. Patient-identified facilitators included self-motivation, financial support, convenient processes for obtaining RZV, and reminders. In conclusion, many factors can influence RZV series completion and adherence among adults in Canada, including cost, insurance coverage, HCP knowledge and encouragement, and reminders. Awareness of these factors may inform HCPs in helping patients overcome barriers and identify opportunities for future consideration, facilitating protection against herpes zoster.
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Vacina contra Herpes Zoster , Herpes Zoster , Adulto , Humanos , Estudos Transversais , Herpes Zoster/prevenção & controle , Herpesvirus Humano 3 , Vacinas Sintéticas , Pessoal de Saúde , CanadáRESUMO
Background: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that can lead to irreversible organ damage (OD). Data describing the patient burden of OD, as compared with SLE without OD, are limited. Objective: To develop a comprehensive conceptual model describing the burden experienced by patients living with SLE-associated OD. Methods: There were three phases to this qualitative study. First, a targeted literature review was conducted to inform a draft conceptual model. Second, key opinion leaders (KOLs) were interviewed to assess the draft conceptual model and help shape patient interview materials. Third, patients of different demographic backgrounds from across the United States were interviewed individually to gather their perspectives on living with SLE-associated OD. Data from concept elicitation interviews with KOLs and patients were coded and analyzed using NVivo software to identify the key concepts of the overall patient burden of SLE-associated OD. Findings from the KOL and patient interviews were used to finalize the conceptual model. Results: KOLs highlighted that SLE-associated OD carried a higher rate of mortality than SLE alone. Participants with SLE-associated OD (n = 40) experienced detrimental impacts across 4 areas of their lives: physical, cognitive, psychosocial functioning, and economic and work-related well-being. Physical impacts were described by all participants, often affecting their ability to perform everyday tasks. Many also described deterioration of cognitive functioning. Almost all participants experienced emotional impacts and challenges to their relationships and social lives resulting from living with SLE-associated OD. Additionally, SLE-associated OD imposed an economic burden including increased healthcare costs. SLE-associated OD had a more severe and debilitating impact on all aspects of the patient's quality of life than SLE prior to OD development, including further limitations in activities of daily living after the development of OD. Discussion: Study findings guided the development of a comprehensive conceptual model that fully represents the patient experience of living with SLE-associated OD, highlighting the additional burden of OD when compared with SLE alone. Conclusions: The conceptual model will inform improvements in disease management, which may result in better patient outcomes and aid development of clinical outcome assessments of disease burden.
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BACKGROUND: Dyskinetic cerebral palsy (DCP), a lifelong neurological disorder beginning in early childhood, manifests with hyperkinetic movements and dystonia. The Movement Disorder-Childhood Rating Scale (MD-CRS) is a clinician-reported outcome measure assessing the intensity of movement disorders and their effect on daily life in pediatric patients. Content validity of clinical outcome assessments is key to accurately capturing patient perspective. Evidence demonstrating content validity of the MD-CRS in patients with DCP is needed. This study captures input from patients with DCP and their caregivers regarding the content validity of the MD-CRS. METHODS: This qualitative, noninterventional, cross-sectional study included interviews with children/adolescents (aged six to 18 years) with DCP and caregivers of children with DCP. Participants were asked to describe body regions and daily functions affected by DCP. Caregivers also reviewed MD-CRS Part I to evaluate the relevance of the items and corresponding response options. Descriptions of DCP were coded and mapped to MD-CRS items and response options. Caregiver feedback on MD-CRS Part I was analyzed using inductive content analysis. RESULTS: Eight patients and 12 caregivers were interviewed. Participants confirmed that the body regions and activities listed in the MD-CRS were affected by DCP and that involuntary movements interfered with all motor, oral/verbal, self-care, and video protocol activities. Caregivers endorsed the response options for 12 of 15 items in MD-CRS Part I and suggested clarifications for others. CONCLUSIONS: Participants confirmed that affected body regions and activities listed in the MD-CRS were relevant to their experience with DCP, demonstrating the content validity of this tool in children/adolescents with DCP.
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Paralisia Cerebral , Discinesias , Distúrbios Distônicos , Transtornos dos Movimentos , Adolescente , Criança , Humanos , Pré-Escolar , Paralisia Cerebral/diagnóstico , Estudos Transversais , Discinesias/diagnóstico , Discinesias/etiologiaRESUMO
BACKGROUND: Information about the impact of respiratory syncytial virus (RSV) on quality of life in older adults is limited. This study characterized the patient experience of RSV illness in USA older adults and assessed the content validity of the InFLUenza Patient Reported Outcome (FLU-PRO) in this population. METHODS: This qualitative, non-interventional, cross-sectional study included hybrid concept elicitation and cognitive debriefing interviews with 30 individuals (age ≥50 years) with polymerase chain reaction-confirmed RSV diagnosed within 6 months of screening. Targeted literature review was first conducted to inform the development of interview materials. Webcam or telephone interviews were conducted by qualitative researchers using a semistructured interview guide. Interview transcripts were coded and analyzed using Excel and NVivo software. RESULTS: All participants reported impacts on daily activities, social activities, and relationships during RSV disease. Physical functioning was impaired in 25 (83%) participants, and 18 (60%) reported not engaging in leisure activities/hobbies. All nine participants who were working reported major impacts on work. Most (n = 28; 93%) described emotional impacts. A majority (n = 19; 63%) reported symptoms lasting beyond the acute disease stage from a week to >1 month. Symptom concepts reported generally matched FLU-PRO items and domains. Cognitive debriefing indicated that FLU-PRO was easy to understand and captured participants' experiences of RSV illness. CONCLUSIONS: This study indicates that RSV disease in adults aged ≥50 years in the USA has substantial impacts on daily life and that the concepts included in FLU-PRO are appropriate and fit for purpose as a measure of RSV symptoms in this population.
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Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Idoso , Estudos Transversais , Humanos , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Infecções por Vírus Respiratório Sincicial/epidemiologiaRESUMO
BACKGROUND & AIMS: Human intestinal epithelial organoids (IEOs) are a powerful tool to model major aspects of intestinal development, health, and diseases because patient-derived cultures retain many features found in vivo. A necessary aspect of the organoid model is the requirement to expand cultures in vitro through several rounds of passaging. This is of concern because the passaging of cells has been shown to affect cell morphology, ploidy, and function. METHODS: Here, we analyzed 173 human IEO lines derived from the small and large bowel and examined the effect of culture duration on DNA methylation (DNAm). Furthermore, we tested the potential impact of DNAm changes on gene expression and cellular function. RESULTS: Our analyses show a reproducible effect of culture duration on DNAm in a large discovery cohort as well as 2 publicly available validation cohorts generated in different laboratories. Although methylation changes were seen in only approximately 8% of tested cytosine-phosphate-guanine dinucleotides (CpGs) and global cellular function remained stable, a subset of methylation changes correlated with altered gene expression at baseline as well as in response to inflammatory cytokine exposure and withdrawal of Wnt agonists. Importantly, epigenetic changes were found to be enriched in genomic regions associated with colonic cancer and distant to the site of replication, indicating similarities to malignant transformation. CONCLUSIONS: Our study shows distinct culture-associated epigenetic changes in mucosa-derived human IEOs, some of which appear to impact gene transcriptomic and cellular function. These findings highlight the need for future studies in this area and the importance of considering passage number as a potentially confounding factor.
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Metilação de DNA , Organoides , Humanos , Intestinos , Epigênese Genética , Mucosa IntestinalRESUMO
BACKGROUND: Patients with rheumatoid arthritis (RA) commonly experience pain despite the availability of disease-modifying treatments. Sleep disturbances are frequently reported in RA, with pain often a contributing factor. The Patient-Reported Outcomes Measurement Information System (PROMIS) Pain Interference and Sleep Disturbance item banks were initially developed to provide insights into the patient experience of pain and sleep, respectively, though they were not specifically intended for use in RA populations. This study evaluated the content validity of the PROMIS Pain Interference and Sleep Disturbance item banks in RA and identified relevant content for short forms for patients with RA that achieved high measurement precision across a broad range of health. METHODS: A qualitative approach consisting of hybrid concept elicitation and cognitive debriefing interviews was used to evaluate the content validity of the item banks in RA. Interviews were semi-structured and open-ended, allowing a range of concepts and responses to be captured. Findings from the qualitative interviews were used to select the most relevant items for the short forms, and psychometric evaluation, using existing item-response theory (IRT) item parameters, was used to evaluate the marginal reliability and measurement precision of the short forms across the range of the latent variables (i.e. pain interference and sleep disturbance). RESULTS: Thirty-two participants were interviewed. Participants reported that RA-related pain and sleep disturbances have substantial impacts on their daily lives, particularly with physical functioning. The PROMIS Pain Interference and Sleep Disturbance item banks were easy to understand and mostly relevant to their RA experiences, and the 7-day recall period was deemed appropriate. Qualitative and IRT-based approaches identified short forms for Pain Interference (11 items) and Sleep Disturbance (7 items) that had high relevance and measurement precision, with good coverage of the concepts identified by participants during concept elicitation. CONCLUSION: Pain and sleep disturbances affect many aspects of daily life in patients with RA and should be considered when novel treatments are developed. This study supports the use of the PROMIS Pain Interference and Sleep Disturbance item banks in RA, and the short forms developed herein have the potential to be used in clinical studies of RA.
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BACKGROUND: Sickle Cell Disease (SCD) is a genetic progressive vascular disease that impacts patients overall health and quality of life. Sickle-cell pain crises (SCPCs) are a hallmark clinical presentation of SCD and have been associated with increased morbidity and mortality. The Sickle Cell Pain Diary- Self Report (SCPD-S) was developed as a daily patient-reported outcome (PRO) measure primarily intended to capture the frequency and severity of SCD-related pain during and outside of a SCPC. The SCPD-S also examines the impact of the pain associated with an SCPC on other health-related quality of life concepts. The objective of this study was to investigate the content validity of the SCPD-S. METHODS: The content validation testing included 18 in-depth hybrid concept elicitation and cognitive debriefing interviews conducted with SCD patients in the US aged 12 years and older. Interviewers used a semi-structured interview guide and a think-aloud approach for the cognitive debriefing portion. All interviews were recorded, transcribed, coded and analyzed. RESULTS: Eighteen interviews across two rounds were conducted. Round 1 hybrid interviews (n = 12) resulted in the expansion of the SCPD-S from 13 to 19 items. Items on the impact of an SCPC on social and recreational activities, sleep, and emotional well-being were added. Five items were significantly revised, as were three response choice sets. Round 2 hybrid interviews (n = 6) confirmed the comprehensiveness of the revised diary, understandability of the wording, and appropriateness of the recall period and response sets. Saturation analyses specific to concept elicitation revealed that no additional interviews were needed. CONCLUSIONS: This study provided evidence to support the content validity of the SCPD-S, a self-report daily diary. Data gathered during patient interviews indicated that the SCPD-S is a fit for purpose measure of SCD and SCPC-related pain frequency and severity and the impact of this pain on other health-related quality of life concepts including fatigue and emotional health. The numerous changes to the SCPD-S as a result of the study findings highlight the importance of the content validation process when developing a PRO measure.
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Aging is characterized by the deterioration of tissue structure and function. In skin, environmental factors, for example, ultraviolet radiation (UVR), can accelerate the effects of aging such as decline in barrier function and subsequent loss of hydration. Water homeostasis is vital for all cellular functions and it is known that organic osmolyte transport is critical to this process. Therefore, we hypothesized that as we age, these tightly controlled physiological mechanisms become disrupted, possibly due to loss of transporter expression. We investigated this in vivo, using human skin samples from photoprotected and photoexposed sites of young and aged volunteers. We show a reduction in keratinocyte cell size with age and a downregulation of osmolyte transporters SMIT and TAUT with both chronic and acute UVR exposure. Single-cell live imaging demonstrated that aged keratinocytes lack efficient cell volume recovery mechanisms possessed by young keratinocytes following physiological stress. However, addition of exogenous taurine significantly rescued cell volume; this was corroborated by a reduction in TAUT mRNA and protein in aged, as compared to young, keratinocytes. Collectively, these novel data demonstrate that human epidermal keratinocytes possess osmolyte-mediated cell volume regulatory mechanisms, which may be compromised in aging. Therefore, this suggests that organic osmolytes-especially taurine-play a critical role in cutaneous age-related xerosis and highlights a fundamental mechanism, vital to our understanding of the pathophysiology of skin aging.
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Proteínas de Membrana Transportadoras/metabolismo , Envelhecimento da Pele/patologia , Pele/metabolismo , Envelhecimento , Humanos , Pele/patologiaRESUMO
In contrast to the dynamic intracellular environment, structural extracellular matrix (ECM) proteins with half-lives measured in decades, are susceptible to accumulating damage. Whilst conventional approaches such as histology, immunohistochemistry and mass spectrometry are able to identify age- and disease-related changes in protein abundance or distribution, these techniques are poorly suited to characterising molecular damage. We have previously shown that mass spectrometry can detect tissue-specific differences in the proteolytic susceptibility of protein regions within fibrillin-1 and collagen VI alpha-3. Here, we present a novel proteomic approach to detect damage-induced "peptide fingerprints" within complex multi-component ECM assemblies (fibrillin and collagen VI microfibrils) following their exposure to ultraviolet radiation (UVR) by broadband UVB or solar simulated radiation (SSR). These assemblies were chosen because, in chronically photoaged skin, fibrillin and collagen VI microfibril architectures are differentially susceptible to UVR. In this study, atomic force microscopy revealed that fibrillin microfibril ultrastructure was significantly altered by UVR exposure whereas the ultrastructure of collagen VI microfibrils was resistant. UVR-induced molecular damage was further characterised by proteolytic peptide generation with elastase followed by liquid chromatography tandem mass spectrometry (LC-MS/MS). Peptide mapping revealed that UVR exposure increased regional proteolytic susceptibility within the protein structures of fibrillin-1 and collagen VI alpha-3. This allowed the identification of UVR-induced molecular changes within these two key ECM assemblies. Additionally, similar changes were observed within protein regions of co-purifying, microfibril-associated receptors integrins αv and ß1. This study demonstrates that LC-MS/MS mapping of peptides enables the characterisation of molecular post-translational damage (via direct irradiation and radiation-induced oxidative mechanisms) within a complex in vitro model system. This peptide fingerprinting approach reliably allows both the identification of UVR-induced molecular damage in and between proteins and the identification of specific protein domains with increased proteolytic susceptibility as a result of photo-denaturation. This has the potential to serve as a sensitive method of identifying accumulated molecular damage in vivo using conventional mass spectrometry data-sets.
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In murine skin, dermal white adipose tissue (DWAT) undergoes major changes in thickness in synchrony with the hair cycle (HC); however, the underlying mechanisms remain unclear. We sought to elucidate whether increased DWAT thickness during anagen is mediated by adipocyte hypertrophy or adipogenesis, and whether lipolysis or apoptosis can explain the decreased DWAT thickness during catagen. In addition, we compared HC-associated DWAT changes between spontaneous and depilation-induced hair follicle (HF) cycling to distinguish between spontaneous and HF trauma-induced events. We show that HC-dependent DWAT remodelling is not an artefact caused by fluctuations in HF down-growth, and that dermal adipocyte (DA) proliferation and hypertrophy are HC-dependent, while classical DA apoptosis is absent. However, none of these changes plausibly accounts for HC-dependent oscillations in DWAT thickness. Contrary to previous studies, in vivo BODIPY uptake suggests that increased DWAT thickness during anagen occurs via hypertrophy rather than hyperplasia. From immunohistomorphometry, DWAT thickness likely undergoes thinning during catagen by lipolysis. Hence, we postulate that progressive, lipogenesis-driven DA hypertrophy followed by dynamic switches between lipogenesis and lipolysis underlie DWAT fluctuations in the spontaneous HC, and dismiss apoptosis as a mechanism of DWAT reduction. Moreover, the depilation-induced HC displays increased DWAT thickness, area, and DA number, but decreased DA volume/area compared to the spontaneous HC. Thus, DWAT shows additional, novel HF wounding-related responses during the induced HC. This systematic reappraisal provides important pointers for subsequent functional and mechanistic studies, and introduces the depilation-induced murine HC as a model for dissecting HF-DWAT interactions under conditions of wounding/stress.
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Tecido Adiposo Branco/patologia , Derme/patologia , Doenças do Cabelo/metabolismo , Folículo Piloso/patologia , Cabelo/fisiologia , Tecido Adiposo Branco/metabolismo , Animais , Apoptose , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Feminino , Doenças do Cabelo/patologia , Remoção de Cabelo , Humanos , Hiperplasia , Hipertrofia , Camundongos , Camundongos Endogâmicos C57BL , PeriodicidadeRESUMO
This study describes the process of adapting and implementing Girls Aspiring toward Independence (GAIN), a trauma-focused, group-based therapy adapted from Cognitive Behavioral Intervention for Trauma in Schools (CBITS) for girls in child welfare. Descriptive data were examined on 3 outcomes: posttraumatic stress disorder (PTSD), depression, and social problem-solving skills among adolescent girls in the child welfare system. Qualitative and quantitative methods were utilized to inform the adaptation of the CBITS intervention, evaluate feasibility, treatment fidelity, and acceptability, and to test the effects of the intervention. Girls ages 12 to 18 (N = 27) were randomly assigned to the experimental and usual care conditions. Participants' symptoms of PTSD and depression and social problem-solving skills were evaluated at pre, post- (3 months), and follow-up (6 months) assessments. Adaptations for GAIN were primarily related to program structure. Data indicated that the program was receptive to girls in child welfare and that it was feasible to recruit, randomize, assess outcomes, and implement with adequate fidelity. Retention was more successful among younger girls. Descriptive initial data showed greater reductions in the percentage of girls with PTSD and depression, and modest increases in social problem-solving skills in the experimental versus usual care condition. Despite the growth of knowledge in dissemination and implementation research, the application of trauma-focused empirically supported treatment to child welfare populations lags behind. A large-scale RCT is needed to determine if GAIN is effective in reducing mental health problems and social problem-solving in the child welfare population. (PsycINFO Database Record