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1.
Nature ; 588(7837): 277-283, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33239791

RESUMO

Advances in genomics have expedited the improvement of several agriculturally important crops but similar efforts in wheat (Triticum spp.) have been more challenging. This is largely owing to the size and complexity of the wheat genome1, and the lack of genome-assembly data for multiple wheat lines2,3. Here we generated ten chromosome pseudomolecule and five scaffold assemblies of hexaploid wheat to explore the genomic diversity among wheat lines from global breeding programs. Comparative analysis revealed extensive structural rearrangements, introgressions from wild relatives and differences in gene content resulting from complex breeding histories aimed at improving adaptation to diverse environments, grain yield and quality, and resistance to stresses4,5. We provide examples outlining the utility of these genomes, including a detailed multi-genome-derived nucleotide-binding leucine-rich repeat protein repertoire involved in disease resistance and the characterization of Sm16, a gene associated with insect resistance. These genome assemblies will provide a basis for functional gene discovery and breeding to deliver the next generation of modern wheat cultivars.


Assuntos
Variação Genética , Genoma de Planta/genética , Genômica , Internacionalidade , Melhoramento Vegetal/métodos , Triticum/genética , Aclimatação/genética , Animais , Centrômero/genética , Centrômero/metabolismo , Mapeamento Cromossômico , Clonagem Molecular , Variações do Número de Cópias de DNA/genética , Elementos de DNA Transponíveis/genética , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Genes de Plantas/genética , Introgressão Genética , Haplótipos , Insetos/patogenicidade , Proteínas NLR/genética , Doenças das Plantas/genética , Proteínas de Plantas/genética , Polimorfismo de Nucleotídeo Único/genética , Poliploidia , Triticum/classificação , Triticum/crescimento & desenvolvimento
2.
Anaesthesia ; 79(7): 706-714, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38177064

RESUMO

Returning to work after maternity leave poses significant challenges, with potential long-term implications including decreased engagement or attrition of clinicians. Many quantitative studies have identified challenges and supports for women during pregnancy, maternity leave and re-entry to clinical practice. This qualitative study explored the experiences of anaesthetists returning to clinical work after maternity leave, to identify influential factors with the aim of providing a framework to assist planning re-entry. We conducted semi-structured interviews with 15 anaesthetists. Attendees of a re-entry programme were invited to participate, with purposive sampling and snowball recruitment to provide diversity of location and training stage, until data saturation was reached at 13 interviews. Five themes were identified: leave duration; planning re-entry; workplace culture; career impact and emotional impact. Leave duration was influenced by concerns about deskilling, but shorter periods of leave had logistical challenges, including fatigue. Most participants started planning to return to work with few or no formal processes in the workplace. Workplace culture, including support for breastfeeding, was identified as valuable, but variable. Participants also experienced negative attitudes on re-entry, including difficulty accessing permanent work, with potential career impacts. Many participants identified changes to professional and personal identity influencing the experience with emotional sequelae. This research describes factors which may be considered to assist clinicians returning to work after maternity leave and identifies challenges, including negative attitudes, which may pose significant barriers to women practising in anaesthesia and may contribute to lack of female leadership in some workplaces.


Assuntos
Licença Parental , Pesquisa Qualitativa , Retorno ao Trabalho , Humanos , Retorno ao Trabalho/psicologia , Feminino , Adulto , Local de Trabalho/psicologia , Gravidez , Anestesistas/psicologia , Atitude do Pessoal de Saúde , Masculino
3.
Anaesthesia ; 79(7): 694-705, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38629288

RESUMO

Gender inequity remains an issue in anaesthesia despite increasing numbers of women training and achieving fellowship in the speciality. Women are under-represented in all areas of anaesthetic research, academia and leadership. The Gender Equity Subcommittee of the Australian and New Zealand College of Anaesthetists recently conducted a survey asking "Does gender still matter in the pursuit of a career in anaesthesia in 2022?". The survey was distributed to a randomly selected sample of 1225 anaesthetic consultants and completed by 470 respondents (38% response rate) with 793 free-text comments provided. Three overarching themes were identified: gender effects on the career and family interface; women do not fit the mould; and gender equity changes the status quo. Women respondents described a need to make a choice between career and family, which was not described by men, as well as stigmatisation of part-time work, a lack of access to challenging work and negative impacts of parental leave. Women respondents also described a sense of marginalisation within anaesthesia due to a 'boys' club' mentality, a lack of professional respect and insufficient structural supports for women in leadership. This was compounded for women from ethnically and culturally diverse backgrounds. A need for specific strategies to support anaesthetic careers for women was described as well as normalisation of flexibility in workplaces, combined with a broadening of our definition of success to allow people of all genders to experience fulfilment both at home and at work. This study is the first published qualitative data on factors affecting gender equity for anaesthetists in Australia and Aotearoa New Zealand. It highlights the need for further exploration, as well providing a foundation for changes in attitude and structural changes towards advancing gender equity.


Assuntos
Anestesiologia , Escolha da Profissão , Humanos , Nova Zelândia , Austrália , Feminino , Masculino , Inquéritos e Questionários , Equidade de Gênero , Adulto , Anestesistas/psicologia , Médicas/psicologia , Anestesiologistas/psicologia , Pesquisa Qualitativa , Sexismo , Pessoa de Meia-Idade
4.
Fam Process ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649331

RESUMO

Attachment theory and the science of emotion provide a strong foundation for intervention at the family system level. Four therapeutic models in particular, Attachment-Based Family Therapy, Emotion-Focused Family Therapy, Dyadic Developmental Psychotherapy, and Emotionally Focused Family Therapy, demonstrate how a broad and accurate view of attachment relationships and emotion can be utilized to effectively intervene for a variety of presenting problems in a relational and empathic way for all involved. This paper continues a conversation that began at the Summit for Attachment and Emotion in Family Therapy in 2021 and aims to foster openness, collaboration, and affirmation between four different models of family therapy with shared theoretical roots. The presenters at the Summit and the authors of this paper view similarities across these models as validating and differences as opportunities to serve more families in unique ways, learning from one another's creativity to promote healing within families in the most effective and efficient ways possible. The paper frames the value of attachment theory and emotion science for family therapy, discusses the importance of learning from a variety of models with shared theoretical roots, presents brief summaries of the four models presented at the Summit, compares the models for similarities and complementarities, and shares highlights from each of the presenters from the Summit.

5.
J Med Virol ; 95(4): e28694, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36946504

RESUMO

The current COVID-19 vaccination program requires frequent booster vaccination to maintain sufficient neutralization levels against immune evasive SARS-CoV-2 variants. However, prior studies found more potent and durable immune response in convalescing individuals, raising the possibility of less frequent booster vaccination for them. Here, we conducted a longitudinal immunological study based on two prospective cohorts of booster vaccinated convalescing COVID-19 patients or healthcare workers (HCW) without COVID-19 history in Xiangyang, China. Comparing to 1-month post-boosting, pseudovirus neutralization titers (pVNT50) of ancestral Wuhan-Hu-1 and circulating omicron sub-variants BA.5, BF.7, BA.4.6, BA.2.75, and BA.2.75.2 spikes were stable or even increased in convalescing samples at 6-month post-boosting, when HCW samples showed substantial drop of neutralization titers across the spectrum. Variant-to-Wuhan-Hu-1 pVNT50 ratios showed no significant variation during the 17 months from pre-vaccination to 6-month post-boosting in convalescing individuals, indicating that the high durability of hybrid immunity was likely sustained by continuously improving neutralization potency that compensated immune decay. Our data provide mechanistic insight into prior epidemiological findings that vaccine-elicited humoral immune response was more durable in convalescing individuals than those without SARS-CoV-2 infection, and suggest further research into potential extension of boosting intervals for convalescing individuals.


Assuntos
COVID-19 , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Estudos Prospectivos , SARS-CoV-2 , Imunidade Humoral , Vacinação , Anticorpos Neutralizantes , Anticorpos Antivirais
6.
J Med Virol ; 95(8): e28999, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37554019

RESUMO

This study (1) determined the association of time since initial vaccine regimen, booster dose receipt, and COVID-19 history with antibody titer, as well as change in titer levels over a defined period, and (2) determined risk of COVID-19 associated with low titer levels. This observational study used data from staff participating in the National Football League COVID-19 Monitoring Program. A cohort of staff consented to antibody-focused sub-study, during which detailed longitudinal data were collected. Among all staff in the program who received antibody testing, COVID-19 incidence following antibody testing was determined. Five hundred eighty-six sub-study participants completed initial antibody testing; 80% (469) completed follow-up testing 50-101 days later. Among 389 individuals who were not boosted at initial testing, the odds of titer < 1000 AU/mL (vs. ≥1000 AU/mL) increased 44% (odds ratio [OR] = 1.44, 95% confidence interval [CI]: 1.18-1.75) for every 30 days since final dose. Among 126 participants boosted before initial testing with no COVID-19 history, 125 (99%) had a value > 2500 AU/ml; 86 (96%) of 90 tested at follow-up and did not develop COVID-19 in the interim remained at that value. One thousand fifty-seven fully vaccinated (330 [29%] boosted at antibody test) individuals participating in the monitoring program were followed to determine COVID-19 status. Individuals with titer value < 1000 AU/mL had twice the risk of COVID-19 as those with >2500 AU/mL (HR = 2.02, 95% CI: 1.28-3.18). Antibody levels decrease postvaccination; boosting increases titer values. While antibody level is not a clear proxy for infection immunity, lower titer values are associated with higher COVID-19 incidence, suggesting increased protection from boosters.


Assuntos
COVID-19 , Humanos , Estudos de Coortes , COVID-19/epidemiologia , COVID-19/prevenção & controle , Testes Imunológicos , Razão de Chances , Vacinação , Anticorpos Antivirais
7.
Osteoarthritis Cartilage ; 31(7): 954-965, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36893979

RESUMO

OBJECTIVE: To develop sets of core and optional recommended domains for describing and evaluating Osteoarthritis Management Programs (OAMPs), with a focus on hip and knee Osteoarthritis (OA). DESIGN: We conducted a 3-round modified Delphi survey involving an international group of researchers, health professionals, health administrators and people with OA. In Round 1, participants ranked the importance of 75 outcome and descriptive domains in five categories: patient impacts, implementation outcomes, and characteristics of the OAMP and its participants and clinicians. Domains ranked as "important" or "essential" by ≥80% of participants were retained, and participants could suggest additional domains. In Round 2, participants rated their level of agreement that each domain was essential for evaluating OAMPs: 0 = strongly disagree to 10 = strongly agree. A domain was retained if ≥80% rated it ≥6. In Round 3, participants rated remaining domains using same scale as in Round 2; a domain was recommended as "core" if ≥80% of participants rated it ≥9 and as "optional" if ≥80% rated it ≥7. RESULTS: A total of 178 individuals from 26 countries participated; 85 completed all survey rounds. Only one domain, "ability to participate in daily activities", met criteria for a core domain; 25 domains met criteria for an optional recommendation: 8 Patient Impacts, 5 Implementation Outcomes, 5 Participant Characteristics, 3 OAMP Characteristics and 4 Clinician Characteristics. CONCLUSION: The ability of patients with OA to participate in daily activities should be evaluated in all OAMPs. Teams evaluating OAMPs should consider including domains from the optional recommended set, with representation from all five categories and based on stakeholder priorities in their local context.


Assuntos
Osteoartrite do Quadril , Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/terapia , Osteoartrite do Quadril/terapia , Consenso , Pessoal de Saúde , Inquéritos e Questionários , Técnica Delphi
8.
Nature ; 603(7903): 796-797, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35355003
9.
Int J Mol Sci ; 24(14)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37511390

RESUMO

New antitubercular agents with either a novel mode of action or novel mode of inhibition are urgently needed to overcome the threat of drug-resistant tuberculosis (TB). The present study profiles new arylated quinoline carboxylic acids (QCAs) having activity against replicating and non-replicating Mycobacterium tuberculosis (Mtb), the causative agent of TB. Thus, the synthesis, characterization, and in vitro screening (MABA and LORA) of 48 QCAs modified with alkyl, aryl, alkoxy, halogens, and nitro groups in the quinoline ring led to the discovery of two QCA derivatives, 7i and 7m, adorned with C-2 2-(naphthalen-2-yl)/C-6 1-butyl and C-2 22-(phenanthren-3-yl)/C-6 isopropyl, respectively, as the best Mtb inhibitors. DNA gyrase inhibition was shown to be exhibited by both, with QCA 7m illustrating better activity up to a 1 µM test concentration. Finally, a docking model for both compounds with Mtb DNA gyrase was developed, and it showed a good correlation with in vitro results.


Assuntos
Mycobacterium tuberculosis , Quinolinas , Mycobacterium tuberculosis/metabolismo , DNA Girase/metabolismo , Ácidos Carboxílicos/farmacologia , Relação Estrutura-Atividade , Antituberculosos/farmacologia , Quinolinas/farmacologia , Testes de Sensibilidade Microbiana , Inibidores da Topoisomerase II/farmacologia
10.
J Biol Chem ; 296: 100207, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33334879

RESUMO

Eukaryotic initiation factor 2B (eIF2B) serves as a vital control point within protein synthesis and regulates translation initiation in response to cellular stress. Mutations within eIF2B result in the fatal disease, leukoencephalopathy with vanishing white matter (VWM). Previous biochemical studies on VWM mutations have illustrated that changes in the activity of eIF2B poorly correlate with disease severity. This suggests that there may be additional characteristics of eIF2B contributing to VWM pathogenesis. Here, we investigated whether the localization of eIF2B to eIF2B bodies was integral for function and whether this localization could provide insight into the pathogenesis of VWM. We demonstrate that the regulatory subunit, eIF2Bα, is required for the assembly of eIF2B bodies in yeast and that loss of eIF2B bodies correlates with an inability of cells to regulate eIF2B activity. Mutational analysis of eIF2Bα showed that missense mutations that disrupt the regulation of eIF2B similarly disrupt the assembly of eIF2B bodies. In contrast, when eIF2Bα mutations that impact the catalytic activity of eIF2B were analyzed, eIF2B bodies were absent and instead eIF2B localized to small foci, termed microfoci. Fluorescence recovery after photobleaching analysis highlighted that within these microfoci, eIF2 shuttles more slowly indicating that formation of eIF2B bodies correlates with full eIF2B activity. When eIF2Bα VWM mutations were analyzed, a diverse impact on localization was observed, which did not seem to correlate with eIF2B activity. These findings provide key insights into how the eIF2B body assembles and suggest that the body is a fundamental part of the translational regulation via eIF2α phosphorylation.


Assuntos
Fator de Iniciação 2 em Eucariotos/genética , Leucoencefalopatias/patologia , Mutação de Sentido Incorreto , Mutação , Processamento de Proteína Pós-Traducional , Saccharomyces cerevisiae/metabolismo , Análise Mutacional de DNA/métodos , Fator de Iniciação 2 em Eucariotos/metabolismo , Humanos , Leucoencefalopatias/genética , Leucoencefalopatias/metabolismo , Mutagênese Sítio-Dirigida/métodos , Biossíntese de Proteínas , Saccharomyces cerevisiae/genética
11.
Epidemiology ; 33(2): 193-199, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34483266

RESUMO

BACKGROUND: The National Football League (NFL) and National Football League Players Association implemented a set of strict protocols for the 2020 season with the intent to mitigate COVID-19 risk among players and staff. In that timeframe, the league's 32 teams completed 256 regular season games and several thousand meetings and practices. In parallel, community cases of COVID-19 were highly prevalent. We assess the risk of holding a 2020 NFL season by comparing community and player COVID-19 infections. METHODS: We used county-level COVID-19 test data from each team to establish baseline distributions of infection rates expected to occur in a population similar in age and sex to NFL players. We used a binomial distribution to simulate expected infections in each community cohort and compared these findings with observed COVID-19 infections in players. RESULTS: Over a 5-month period (1 August 2020 to 2 January 2021), positive NFL player infections (n = 256) were 55.7% lower than expected when compared with simulations from NFL community cohorts. For 30 of 32 teams (94%), observed counts fell at or below expectation, including 28 teams (88%) for which rates were lower. Two teams fell above baseline expectation. CONCLUSIONS: The NFL/NFLPA protocols that governed team facilities, travel, gameday, and activities outside of the workplace were associated with lower infection rates among NFL players compared with the surrounding community. The NFL's 2020-2021 season are consistent with the hypothesis that robust testing and behavioral protocols support a safe return to sport and work.


Assuntos
COVID-19 , Futebol Americano , Estudos de Coortes , Humanos , SARS-CoV-2 , Estações do Ano
12.
Osteoarthritis Cartilage ; 30(4): 586-595, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35017058

RESUMO

OBJECTIVES: Functional changes in the autonomic nervous system may help explain variability in the progression of knee osteoarthritis (OA). Thus, the objective of this study was to evaluate autonomic nervous system shifts, measured via heart rate response variables, in rat knee joint injury and OA models. METHODS: Cardiovascular characteristics were measured at baseline and bi-weekly for 8 weeks after skin incision, medial collateral ligament transection (MCLT), or MCLT+medial meniscus transection (MCLT+MMT). Heart rate was also assessed during a mild stressor (elevated maze). At endpoint, cardiovascular responses to mechanical knee stimuli were evaluated, as well as responses to 1-phenylbiguanide, a 5HT3A receptor agonist with reported ability to stimulate vagal responses. RESULTS: During low activity, a slower heart rate occurred in MCLT (299 ± 10 bpm) and MCLT+MMT (310 ± 10 bpm) animals compared to controls (325 ± 10 bpm). Furthermore, patellar ligament mechanical stimuli produced an immediate decrease in heart rate and blood pressure in all groups. Finally, a larger drop in heart rate was observed in MCLT (252 ± 40 bpm) and MCLT+MMT (263 ± 49 bpm) following administration of 1-phenylbiguanide compared to skin incision (168 ± 45 bpm). CONCLUSIONS: Acute mechanical stimulation of the patellar ligament produced drops in heart rate, suggesting a possible joint-brain connection that modulates autonomic responses. With both joint injury, cardiac vagal activation was altered in response to pharmacological stimulation, with chronic longitudinal heart rate reduction. These data provide some preliminary evidence of potential functional shifts in autonomic nervous system function in models of joint injury and OA.


Assuntos
Traumatismos do Joelho , Osteoartrite do Joelho , Lesões do Menisco Tibial , Animais , Sistema Nervoso Autônomo , Frequência Cardíaca , Articulação do Joelho , Masculino , Ratos , Ratos Endogâmicos Lew
13.
Osteoarthritis Cartilage ; 30(2): 184-195, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34534661

RESUMO

OBJECTIVE: To summarize the current state of the evidence regarding osteoarthritis (OA) prevalence, incidence and risk factors at the person-level and joint-level. DESIGN: This was a narrative review that took a comprehensive approach regarding inclusion of potential risk factors. The review complements prior reviews of OA epidemiology, with a focus on new research and emerging topics since 2017, as well as seminal studies. RESULTS: Studies continue to illustrate the high prevalence of OA worldwide, with a greater burden among older individuals, women, some racial and ethnic groups, and individuals with lower socioeconomic status. Modifiable risk factors for OA with the strongest evidence are obesity and joint injury. Topics of high interest or emerging evidence for a potential association with OA risk or progression include specific vitamins and diets, high blood pressure, genetic factors, metformin use, bone mineral density, abnormal joint shape and malalignment, and lower muscle strength/quality. Studies also continue to highlight the heterogenous nature of OA, with strong interest in understanding and defining OA phenotypes. CONCLUSIONS: OA is an increasingly prevalent condition with worldwide impacts on many health outcomes. The strong evidence for obesity and joint injury as OA risk factors calls for heightened efforts to mitigate these risks at clinical and public health levels. There is also a need for continued research regarding how potential person- and joint-level risk factors may interact to influence the development and progression of OA.


Assuntos
Osteoartrite/epidemiologia , Humanos , Incidência , Prevalência , Fatores de Risco
14.
Heart Vessels ; 37(2): 347-358, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34727208

RESUMO

Calcific aortic valve disease (CAVD) is the most common heart valve disease requiring intervention. Most research on CAVD has focused on inflammation, ossification, and cellular phenotype transformation. To gain a broader picture into the wide range of cellular and molecular mechanisms involved in this disease, we compared the total protein profiles between calcified and non-calcified areas from 5 human valves resected during surgery. The 1413 positively identified proteins were filtered down to 248 proteins present in both calcified and non-calcified segments of at least 3 of the 5 valves, which were then analyzed using Ingenuity Pathway Analysis. Concurrently, the top 40 differentially abundant proteins were grouped according to their biological functions and shown in interactive networks. Finally, the abundance of selected osteogenic proteins (osteopontin, osteonectin, osteocalcin, osteoprotegerin, and RANK) was quantified using ELISA and/or immunohistochemistry. The top pathways identified were complement system, acute phase response signaling, metabolism, LXR/RXR and FXR/RXR activation, actin cytoskeleton, mineral binding, nucleic acid interaction, structural extracellular matrix (ECM), and angiogenesis. There was a greater abundance of osteopontin, osteonectin, osteocalcin, osteoprotegerin, and RANK in the calcified regions than the non-calcified ones. The osteogenic proteins also formed key connections between the biological signaling pathways in the network model. In conclusion, this proteomic analysis demonstrated the involvement of multiple signaling pathways in CAVD. The interconnectedness of these pathways provides new insights for the treatment of this disease.


Assuntos
Estenose da Valva Aórtica , Calcinose , Valva Aórtica/metabolismo , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/metabolismo , Estenose da Valva Aórtica/cirurgia , Calcinose/metabolismo , Humanos , Osteogênese/fisiologia , Proteoma/metabolismo , Proteômica
15.
Hong Kong Med J ; 28(2): 161-168, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35400644

RESUMO

Breast cancer (BC) is the most common cancer among women in Hong Kong. The Food and Health Bureau commissioned The University of Hong Kong (HKU) to conduct the Hong Kong Breast Cancer Study (HKBCS) with the aim of identifying relevant risk factors for BC in Hong Kong and developing a locally validated BC risk assessment tool for Hong Kong Chinese women. After consideration of the most recent international and local scientific evidence including findings of the HKBCS, the Cancer Expert Working Group on Cancer Prevention and Screening (CEWG) has reviewed and updated its BC screening recommendations. Existing recommendations were preserved for women at high risk and slightly changed for women at moderate risk. The following major updates have been made concerning recommendations for other women in the general population: Women aged 44 to 69 with certain combinations of personalised risk factors (including presence of history of BC among first-degree relative, a prior diagnosis of benign breast disease, nulliparity and late age of first live birth, early age of menarche, high body mass index and physical inactivity) putting them at increased risk of BC are recommended to consider mammography screening every 2 years. They should discuss with their doctors on the potential benefits and harms before undergoing mammography screening. A risk assessment tool for local women (eg, one developed by HKU) is recommended to be used for estimating the risk of developing BC with regard to the personalised risk factors described above.


Assuntos
Neoplasias da Mama , Detecção Precoce de Câncer , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/prevenção & controle , Feminino , Hong Kong/epidemiologia , Humanos , Masculino , Mamografia , Programas de Rastreamento , Medição de Risco
16.
Physiol Genomics ; 53(11): 486-508, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34612061

RESUMO

Human intestinal epithelial organoids (enteroids and colonoids) are tissue cultures used for understanding the physiology of the human intestinal epithelium. Here, we explored the effect on the transcriptome of common variations in culture methods, including extracellular matrix substrate, format, tissue segment, differentiation status, and patient heterogeneity. RNA-sequencing datasets from 276 experiments performed on 37 human enteroid and colonoid lines from 29 patients were aggregated from several groups in the Texas Medical Center. DESeq2 and gene set enrichment analysis (GSEA) were used to identify differentially expressed genes and enriched pathways. PERMANOVA, Pearson's correlation, and dendrogram analysis of the data originally indicated three tiers of influence of culture methods on transcriptomic variation: substrate (collagen vs. Matrigel) and format (3-D, transwell, and monolayer) had the largest effect; segment of origin (duodenum, jejunum, ileum, colon) and differentiation status had a moderate effect; and patient heterogeneity and specific experimental manipulations (e.g., pathogen infection) had the smallest effect. GSEA identified hundreds of pathways that varied between culture methods, such as IL1 cytokine signaling enriched in transwell versus monolayer cultures and E2F target genes enriched in collagen versus Matrigel cultures. The transcriptional influence of the format was furthermore validated in a synchronized experiment performed with various format-substrate combinations. Surprisingly, large differences in organoid transcriptome were driven by variations in culture methods such as format, whereas experimental manipulations such as infection had modest effects. These results show that common variations in culture conditions can have large effects on intestinal organoids and should be accounted for when designing experiments and comparing results between laboratories. Our data constitute the largest RNA-seq dataset interrogating human intestinal epithelial organoids.


Assuntos
Técnicas de Cultura de Células/métodos , Colo/metabolismo , Meios de Cultura/farmacologia , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Organoides/metabolismo , Transcriptoma/efeitos dos fármacos , Calcitriol/farmacologia , Colágeno/metabolismo , Colágeno/farmacologia , Doença de Crohn/metabolismo , Doença de Crohn/patologia , Meios de Cultura/química , Combinação de Medicamentos , Escherichia coli , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/microbiologia , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Laminina/metabolismo , Laminina/farmacologia , Organoides/virologia , Proteoglicanas/metabolismo , Proteoglicanas/farmacologia , RNA-Seq/métodos , Transcriptoma/genética , Viroses/metabolismo , Viroses/virologia , Vírus
17.
Osteoarthritis Cartilage ; 29(9): 1351-1361, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34052396

RESUMO

OBJECTIVE: Tissues have complex structures, comprised of solid and fluid phases. Improved understanding of interactions between joint fluid and extracellular matrix (ECM) is required in models of cartilage mechanics. X-ray photon correlation spectroscopy (XPCS) directly measures nanometer-scale dynamics and can provide insight into biofluid-biosolid interactions in cartilage. This study applies XPCS to evaluate dynamic interactions between intact cartilage and biofluids. DESIGN: Cartilage biopsies were collected from bovine femoral condyles. During XPCS measurements, cartilage samples were exposed to different fluids: deionized water, PBS, synovial fluid, or sonicated synovial fluid. ECM-biofluid interactions were also assessed at different length scales and different depths from the cartilage surface. RESULTS: Using XPCS, cartilage ECM mobility was detected at length scales from 50 to 207 nm. As length scale decreased, time scale for autocorrelation decay decreased, suggesting smaller ECM components are more mobile. ECM dynamics were slowed by dehydrating the sample, demonstrating XPCS assesses matrix mobility in hydrated environments. At all length scales, the matrix was more mobile in deionized water and slowest in synovial fluid. Using the 207 nm length scale assessment, ECM dynamics in synovial fluid were fastest at the cartilage surface and progressively slowed as depth into the sample increased, demonstrating XPCS can assess spatial distribution of ECM dynamics. Finally, ECM mobility increased for degraded synovial fluid. CONCLUSIONS: This study demonstrates the potential of XPCS to provide unique insights into nanometer-scale cartilage ECM mobility in a spatially resolved manner and illustrates the importance of biosolid-biofluid interactions in dictating ECM dynamics.


Assuntos
Cartilagem Articular/anatomia & histologia , Cartilagem Articular/fisiologia , Matriz Extracelular , Líquido Sinovial , Animais , Bovinos , Análise Espectral
18.
Biopolymers ; 112(10): e23416, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33462801

RESUMO

Although most experimentally characterized proteins with similar sequences assume the same folds and perform similar functions, an increasing number of exceptions is emerging. One class of exceptions comprises sequence-similar fold switchers, whose secondary structures shift from α-helix <-> ß-sheet through a small number of mutations, a sequence insertion, or a deletion. Predictive methods for identifying sequence-similar fold switchers are desirable because some are associated with disease and/or can perform different functions in cells. Here, we use homology-based secondary structure predictions to identify sequence-similar fold switchers from their amino acid sequences alone. To do this, we predicted the secondary structures of sequence-similar fold switchers using three different homology-based secondary structure predictors: PSIPRED, JPred4, and SPIDER3. We found that α-helix <-> ß-strand prediction discrepancies from JPred4 discriminated between the different conformations of sequence-similar fold switchers with high statistical significance (P < 1.8*10-19 ). Thus, we used these discrepancies as a classifier and found that they can often robustly discriminate between sequence-similar fold switchers and sequence-similar proteins that maintain the same folds (Matthews Correlation Coefficient of 0.82). We found that JPred4 is a more robust predictor of sequence-similar fold switchers because of (a) the curated sequence database it uses to produce multiple sequence alignments and (b) its use of sequence profiles based on Hidden Markov Models. Our results indicate that inconsistencies between JPred4 secondary structure predictions can be used to identify some sequence-similar fold switchers from their sequences alone. Thus, the negative information from inconsistent secondary structure predictions can potentially be leveraged to identify sequence-similar fold switchers from the broad base of genomic sequences.


Assuntos
Dobramento de Proteína , Proteínas , Sequência de Aminoácidos , Estrutura Secundária de Proteína , Alinhamento de Sequência
19.
Biotechnol Bioeng ; 118(8): 2958-2966, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33913514

RESUMO

This study investigated the chondrogenic activity of encapsulated mesenchymal stem cells (MSCs) and articular chondrocytes (ACs) and its impact on the mechanical properties of injectable poly(N-isopropylacrylamide)-based dual-network hydrogels loaded with poly( l -lysine) (PLL). To this effect, an ex vivo study model was employed to assess the behavior of the injected hydrogels-specifically, their surface stiffness and integration strength with the surrounding cartilage. The highest chondrogenic activity was observed from AC-encapsulated hydrogels, while the effect of PLL on MSC chondrogenesis was not apparent from biochemical analyses. Mechanical testing showed that there were no significant differences in either surface stiffness or integration strength among the different study groups. Altogether, the results suggest that the ex vivo model can allow further understanding of the relationship between biochemical changes within the hydrogel and their impact on the hydrogel's mechanical properties.


Assuntos
Cartilagem Articular/metabolismo , Diferenciação Celular , Condrócitos/metabolismo , Condrogênese , Hidrogéis/química , Células-Tronco Mesenquimais/metabolismo , Engenharia Tecidual , Animais , Cartilagem Articular/citologia , Condrócitos/citologia , Técnicas de Cocultura , Células-Tronco Mesenquimais/citologia , Coelhos
20.
BMC Health Serv Res ; 21(1): 430, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33952263

RESUMO

BACKGROUND: Caring for a growing aging population using existing long-term care resources while simultaneously supporting and educating family caregivers, is a public health challenge. We describe the application of the Replicating Effective Programs (REP) framework, developed by the Centers for Disease Control Prevention and used in public health program implementation, to scale up an evidence-based family caregiver training intervention in the Veterans Affairs (VA) healthcare system. METHODS: From 2018 to 2020, clinicians at eight VA medical centers received REP-guided implementation including facilitation, technical assistance, and implementation tools to deliver the training program. The project team used the REP framework to develop activities across four distinct phases - (1) pre-conditions, (2) pre-implementation, (3) implementation, and (4) maintenance and evolution - and systematically tracked implementation facilitators, barriers, and adaptations. RESULTS: Within the REP framework, results describe how each medical center adapted implementation approaches to fit local needs. We highlight examples of how sites balanced adaptations and intervention fidelity. CONCLUSIONS: The REP framework shows promise for national expansion of the caregiver training intervention, including to non-VA systems of care, because it allows sites to adapt while maintaining intervention fidelity. TRIAL REGISTRATION: NCT03474380 . Date registered: March 22, 2018.


Assuntos
Cuidadores , Veteranos , Aconselhamento , Promoção da Saúde , Humanos , Estados Unidos , United States Department of Veterans Affairs
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