Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 660
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Cell ; 165(5): 1267-1279, 2016 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-27180905

RESUMO

RNA has the intrinsic property to base pair, forming complex structures fundamental to its diverse functions. Here, we develop PARIS, a method based on reversible psoralen crosslinking for global mapping of RNA duplexes with near base-pair resolution in living cells. PARIS analysis in three human and mouse cell types reveals frequent long-range structures, higher-order architectures, and RNA-RNA interactions in trans across the transcriptome. PARIS determines base-pairing interactions on an individual-molecule level, revealing pervasive alternative conformations. We used PARIS-determined helices to guide phylogenetic analysis of RNA structures and discovered conserved long-range and alternative structures. XIST, a long noncoding RNA (lncRNA) essential for X chromosome inactivation, folds into evolutionarily conserved RNA structural domains that span many kilobases. XIST A-repeat forms complex inter-repeat duplexes that nucleate higher-order assembly of the key epigenetic silencing protein SPEN. PARIS is a generally applicable and versatile method that provides novel insights into the RNA structurome and interactome. VIDEO ABSTRACT.


Assuntos
Ficusina/química , RNA de Cadeia Dupla/química , Animais , Pareamento de Bases , Células HEK293 , Células HeLa , Humanos , Camundongos , Células-Tronco Embrionárias Murinas , RNA Longo não Codificante/química
2.
Nature ; 633(8028): 120-126, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39085610

RESUMO

The Cambrian radiation of euarthropods can be attributed to an adaptable body plan. Sophisticated brains and specialized feeding appendages, which are elaborations of serially repeated organ systems and jointed appendages, underpin the dominance of Euarthropoda in a broad suite of ecological settings. The origin of the euarthropod body plan from a grade of vermiform taxa with hydrostatic lobopodous appendages ('lobopodian worms')1,2 is founded on data from Burgess Shale-type fossils. However, the compaction associated with such preservation obscures internal anatomy3-6. Phosphatized microfossils provide a complementary three-dimensional perspective on early crown group euarthropods7, but few lobopodians8,9. Here we describe the internal and external anatomy of a three-dimensionally preserved euarthropod larva with lobopods, midgut glands and a sophisticated head. The architecture of the nervous system informs the early configuration of the euarthropod brain and its associated appendages and sensory organs, clarifying homologies across Panarthropoda. The deep evolutionary position of Youti yuanshi gen. et sp. nov. informs the sequence of character acquisition during arthropod evolution, demonstrating a deep origin of sophisticated haemolymph circulatory systems, and illuminating the internal anatomical changes that propelled the rise and diversification of this enduringly successful group.


Assuntos
Artrópodes , Fósseis , Larva , Animais , Artrópodes/anatomia & histologia , Artrópodes/classificação , Evolução Biológica , Cabeça/anatomia & histologia , Larva/anatomia & histologia , Sistema Nervoso/anatomia & histologia , Filogenia , Hemolinfa
3.
Nature ; 615(7952): 468-471, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36890226

RESUMO

The animal phyla and their associated body plans originate from a singular burst of evolution occurring during the Cambrian period, over 500 million years ago1. The phylum Bryozoa, the colonial 'moss animals', have been the exception: convincing skeletons of this biomineralizing clade have been absent from Cambrian strata, in part because potential bryozoan fossils are difficult to distinguish from the modular skeletons of other animal and algal groups2,3. At present, the strongest candidate4 is the phosphatic microfossil Protomelission5. Here we describe exceptionally preserved non-mineralized anatomy in Protomelission-like macrofossils from the Xiaoshiba Lagerstätte6. Taken alongside the detailed skeletal construction and the potential taphonomic origin of 'zooid apertures', we consider that Protomelission is better interpreted as the earliest dasycladalean green alga-emphasizing the ecological role of benthic photosynthesizers in early Cambrian communities. Under this interpretation, Protomelission cannot inform the origins of the bryozoan body plan; despite a growing number of promising candidates7-9, there remain no unequivocal bryozoans of Cambrian age.


Assuntos
Briozoários , Clorófitas , Fósseis , Filogenia , Animais , Briozoários/anatomia & histologia , Briozoários/classificação , Fosfatos/metabolismo , Clorófitas/anatomia & histologia , Clorófitas/classificação , Fotossíntese , China
4.
Nature ; 615(7952): 430-435, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36922609

RESUMO

The control of tetrahedral carbon stereocentres remains a focus of modern synthetic chemistry and is enabled by their configurational stability. By contrast, trisubstituted nitrogen1, phosphorus2 and sulfur compounds3 undergo pyramidal inversion, a fundamental and well-recognized stereochemical phenomenon that is widely exploited4. However, the stereochemistry of oxonium ions-compounds bearing three substituents on a positively charged oxygen atom-is poorly developed and there are few applications of oxonium ions in synthesis beyond their existence as reactive intermediates5,6. There are no examples of configurationally stable oxonium ions in which the oxygen atom is the sole stereogenic centre, probably owing to the low barrier to oxygen pyramidal inversion7 and the perception that all oxonium ions are highly reactive. Here we describe the design, synthesis and characterization of a helically chiral triaryloxonium ion in which inversion of the oxygen lone pair is prevented through geometric restriction to enable it to function as a determinant of configuration. A combined synthesis and quantum calculation approach delineates design principles that enable configurationally stable and room-temperature isolable salts to be generated. We show that the barrier to inversion is greater than 110 kJ mol-1 and outline processes for resolution. This constitutes, to our knowledge, the only example of a chiral non-racemic and configurationally stable molecule in which the oxygen atom is the sole stereogenic centre.

5.
Cell ; 146(4): 645-58, 2011 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-21854988

RESUMO

The human mitochondrial genome comprises a distinct genetic system transcribed as precursor polycistronic transcripts that are subsequently cleaved to generate individual mRNAs, tRNAs, and rRNAs. Here, we provide a comprehensive analysis of the human mitochondrial transcriptome across multiple cell lines and tissues. Using directional deep sequencing and parallel analysis of RNA ends, we demonstrate wide variation in mitochondrial transcript abundance and precisely resolve transcript processing and maturation events. We identify previously undescribed transcripts, including small RNAs, and observe the enrichment of several nuclear RNAs in mitochondria. Using high-throughput in vivo DNaseI footprinting, we establish the global profile of DNA-binding protein occupancy across the mitochondrial genome at single-nucleotide resolution, revealing regulatory features at mitochondrial transcription initiation sites and functional insights into disease-associated variants. This integrated analysis of the mitochondrial transcriptome reveals unexpected complexity in the regulation, expression, and processing of mitochondrial RNA and provides a resource for future studies of mitochondrial function (accessed at http://mitochondria.matticklab.com).


Assuntos
Perfilação da Expressão Gênica , Mitocôndrias/genética , RNA/análise , Núcleo Celular/metabolismo , Pegada de DNA , Proteínas de Ligação a DNA/análise , Desoxirribonuclease I/metabolismo , Regulação da Expressão Gênica , Genoma Mitocondrial , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Região de Controle de Locus Gênico , Proteínas Mitocondriais/análise , Conformação de Ácido Nucleico , RNA/metabolismo , RNA Mitocondrial , Análise de Sequência de RNA
6.
Proc Natl Acad Sci U S A ; 120(4): e2209481119, 2023 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-36649427

RESUMO

Bioarchaeological evidence of interpersonal violence and early warfare presents important insights into conflict in past societies. This evidence is critical for understanding the motivations for violence and its effects on opposing and competing individuals and groups across time and space. Selecting the Neolithic of northwestern Europe as an area for study, the present paper examines the variation and societal context for the violence recorded in the human skeletal remains from this region as one of the most important elements of human welfare. Compiling data from various sources, it becomes apparent that violence was endemic in Neolithic Europe, sometimes reaching levels of intergroup hostilities that ended in the utter destruction of entire communities. While the precise comparative quantification of healed and unhealed trauma remains a fundamental problem, patterns emerge that see conflict likely fostered by increasing competition between settled and growing communities, e.g., for access to arable land for food production. The further development of contextual information is paramount in order to address hypotheses on the motivations, origins, and evolution of violence as based on the study of human remains, the most direct indicator for actual small- and large-scale violence.


Assuntos
Fazendeiros , Violência , Humanos , Guerra , Europa (Continente)
7.
Proc Natl Acad Sci U S A ; 120(41): e2215676120, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37782803

RESUMO

Scientists seek to understand the causal processes that generate sustainability problems and determine effective solutions. Yet, causal inquiry in nature-society systems is hampered by conceptual and methodological challenges that arise from nature-society interdependencies and the complex dynamics they create. Here, we demonstrate how sustainability scientists can address these challenges and make more robust causal claims through better integration between empirical analyses and process- or agent-based modeling. To illustrate how these different epistemological traditions can be integrated, we present four studies of air pollution regulation, natural resource management, and the spread of COVID-19. The studies show how integration can improve empirical estimates of causal effects, inform future research designs and data collection, enhance understanding of the complex dynamics that underlie observed temporal patterns, and elucidate causal mechanisms and the contexts in which they operate. These advances in causal understanding can help sustainability scientists develop better theories of phenomena where social and ecological processes are dynamically intertwined and prior causal knowledge and data are limited. The improved causal understanding also enhances governance by helping scientists and practitioners choose among potential interventions, decide when and how the timing of an intervention matters, and anticipate unexpected outcomes. Methodological integration, however, requires skills and efforts of all involved to learn how members of the respective other tradition think and analyze nature-society systems.


Assuntos
Poluição do Ar , COVID-19 , Humanos , Conservação dos Recursos Naturais , Análise de Sistemas , Recursos Naturais
8.
Proc Natl Acad Sci U S A ; 119(26): e2119686119, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35737838

RESUMO

Allostery is the phenomenon of coupling between distal binding sites in a protein. Such coupling is at the crux of protein function and regulation in a myriad of scenarios, yet determining the molecular mechanisms of coupling networks in proteins remains a major challenge. Here, we report mechanisms governing pH-dependent myristoyl switching in monomeric hisactophilin, whereby the myristoyl moves between a sequestered state, i.e., buried within the core of the protein, to an accessible state, in which the myristoyl has increased accessibility for membrane binding. Measurements of the pH and temperature dependence of amide chemical shifts reveal protein local structural stability and conformational heterogeneity that accompany switching. An analysis of these measurements using a thermodynamic cycle framework shows that myristoyl-proton coupling at the single-residue level exists in a fine balance and extends throughout the protein. Strikingly, small changes in the stereochemistry or size of core and surface hydrophobic residues by point mutations readily break, restore, or tune myristoyl switch energetics. Synthesizing the experimental results with those of molecular dynamics simulations illuminates atomistic details of coupling throughout the protein, featuring a large network of hydrophobic interactions that work in concert with key electrostatic interactions. The simulations were critical for discerning which of the many ionizable residues in hisactophilin are important for switching and identifying the contributions of nonnative interactions in switching. The strategy of using temperature-dependent NMR presented here offers a powerful, widely applicable way to elucidate the molecular mechanisms of allostery in proteins at high resolution.


Assuntos
Proteínas dos Microfilamentos , Proteínas de Protozoários , Genes de Troca , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Proteínas dos Microfilamentos/química , Proteínas dos Microfilamentos/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismo , Transdução de Sinais , Eletricidade Estática
9.
BMC Biol ; 22(1): 249, 2024 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-39468514

RESUMO

BACKGROUND: The Leishmania genome harbors formerly active short interspersed degenerated retroposons (SIDERs) representing the largest family of repetitive elements among trypanosomatids. Their substantial expansion in Leishmania is a strong predictor of important biological functions. In this study, we combined multilevel bioinformatic predictions with high-throughput genomic and transcriptomic analyses to gain novel insights into the diversified roles retroposons of the SIDER2 subfamily play in Leishmania genome evolution and expression. RESULTS: We show that SIDER2 retroposons form various evolutionary divergent clusters, each harboring homologous SIDER2 sequences usually located nearby in the linear sequence of chromosomes. This intriguing genomic organization underscores the importance of SIDER2 proximity in shaping chromosome dynamics and co-regulation. Accordingly, we show that transcripts belonging to the same SIDER2 cluster can display similar levels of expression. SIDER2 retroposons are mostly transcribed as part of 3'UTRs and account for 13% of the Leishmania transcriptome. Genome-wide expression profiling studies underscore SIDER2 association generally with low mRNA expression. The remarkable link of SIDER2 retroposons with downregulation of gene expression supports their co-option as major regulators of mRNA abundance. SIDER2 sequences also add to the diversification of the Leishmania gene expression repertoire since ~ 35% of SIDER2-containing transcripts can be differentially regulated throughout the parasite development, with a few encoding key virulence factors. In addition, we provide evidence for a functional bias of SIDER2-containing transcripts with protein kinase and transmembrane transporter activities being most represented. CONCLUSIONS: Altogether, these findings provide important conceptual advances into evolutionary innovations of transcribed extinct retroposons acting as major RNA cis-regulators.


Assuntos
Evolução Molecular , Leishmania , RNA Mensageiro , Retroelementos , Retroelementos/genética , Leishmania/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Genoma de Protozoário , Regulação da Expressão Gênica no Desenvolvimento , RNA de Protozoário/genética , RNA de Protozoário/metabolismo
10.
Genome Res ; 31(7): 1174-1186, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34158368

RESUMO

The testis transcriptome is highly complex and includes RNAs that potentially hybridize to form double-stranded RNA (dsRNA). We isolated dsRNA using the monoclonal J2 antibody and deep-sequenced the enriched samples from testes of juvenile Dicer1 knockout mice, age-matched controls, and adult animals. Comparison of our data set with recently published data from mouse liver revealed that the dsRNA transcriptome in testis is markedly different from liver: In testis, dsRNA-forming transcripts derive from mRNAs including promoters and immediate downstream regions, whereas in somatic cells they originate more often from introns and intergenic transcription. The genes that generate dsRNA are significantly expressed in isolated male germ cells with particular enrichment in pachytene spermatocytes. dsRNA formation is lower on the sex (X and Y) chromosomes. The dsRNA transcriptome is significantly less complex in juvenile mice as compared to adult controls and, possibly as a consequence, the knockout of Dicer1 has only a minor effect on the total number of transcript peaks associated with dsRNA. The comparison between dsRNA-associated genes in testis and liver with a reported set of genes that produce endogenous siRNAs reveals a significant overlap in testis but not in liver. Testis dsRNAs also significantly associate with natural antisense genes-again, this feature is not observed in liver. These findings point to a testis-specific mechanism involving natural antisense transcripts and the formation of dsRNAs that feed into the RNA interference pathway, possibly to mitigate the mutagenic impacts of recombination and transposon mobilization.

11.
J Virol ; 97(11): e0070523, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37843370

RESUMO

IMPORTANCE: The lack of a reliable method to accurately detect when replication-competent HIV has been cleared is a major challenge in developing a cure. This study introduces a new approach called the HIVepsilon-seq (HIVε-seq) assay, which uses long-read sequencing technology and bioinformatics to scrutinize the HIV genome at the nucleotide level, distinguishing between defective and intact HIV. This study included 30 participants on antiretroviral therapy, including 17 women, and was able to discriminate between defective and genetically intact viruses at the single DNA strand level. The HIVε-seq assay is an improvement over previous methods, as it requires minimal sample, less specialized lab equipment, and offers a shorter turnaround time. The HIVε-seq assay offers a promising new tool for researchers to measure the intact HIV reservoir, advancing efforts towards finding a cure for this devastating disease.


Assuntos
Infecções por HIV , HIV , Provírus , Feminino , Humanos , Linfócitos T CD4-Positivos , DNA Viral/genética , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Nucleotídeos , Provírus/genética , Carga Viral , Análise de Sequência de DNA , Masculino , Fatores Sexuais , HIV/genética
12.
New Phytol ; 242(2): 351-371, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38416367

RESUMO

Tropical forest root characteristics and resource acquisition strategies are underrepresented in vegetation and global models, hampering the prediction of forest-climate feedbacks for these carbon-rich ecosystems. Lowland tropical forests often have globally unique combinations of high taxonomic and functional biodiversity, rainfall seasonality, and strongly weathered infertile soils, giving rise to distinct patterns in root traits and functions compared with higher latitude ecosystems. We provide a roadmap for integrating recent advances in our understanding of tropical forest belowground function into vegetation models, focusing on water and nutrient acquisition. We offer comparisons of recent advances in empirical and model understanding of root characteristics that represent important functional processes in tropical forests. We focus on: (1) fine-root strategies for soil resource exploration, (2) coupling and trade-offs in fine-root water vs nutrient acquisition, and (3) aboveground-belowground linkages in plant resource acquisition and use. We suggest avenues for representing these extremely diverse plant communities in computationally manageable and ecologically meaningful groups in models for linked aboveground-belowground hydro-nutrient functions. Tropical forests are undergoing warming, shifting rainfall regimes, and exacerbation of soil nutrient scarcity caused by elevated atmospheric CO2. The accurate model representation of tropical forest functions is crucial for understanding the interactions of this biome with the climate.


Las características de las raíces de los bosques tropicales y las estrategias de adquisición de recursos están subrepresentadas en modelos de vegetación, lo que dificulta la predicción del efecto de cambio de clima para estos ecosistemas ricos en carbono. Los bosques tropicales a menudo tienen combinaciones únicas a nivel mundial de alta biodiversidad taxonómica y funcional, estacionalidad de precipitación, y suelos infértiles, dando lugar a patrones distintos en los rasgos y funciones de las raíces en comparación con los ecosistemas de latitudes más altas. Integramos los avances recientes en nuestra comprensión de la función subterránea de los bosques tropicales en modelos de vegetación, centrándonos en la adquisición de agua y nutrientes. Ofrecemos comparaciones de avances recientes en la comprensión empírica y de modelos de las características de las raíces que representan procesos funcionales importantes en los bosques tropicales. Nos centramos en: (1) estrategias de raíces finas para adquisición de recursos del suelo, (2) acoplamiento y compensaciones entre adquisición del agua y de nutrientes, y (3) vínculos entre funciones sobre tierra y debajo del superficie en bosques tropicales. Sugerimos vías para representar estas comunidades de plantas extremadamente diversas en grupos computacionalmente manejables y ecológicamente significativos en modelos. Los bosques tropicales se están calentando, tienen cambios en los regímenes de lluvias, y tienen una exacerbación de la escasez de nutrientes del suelo causada por el elevado CO2 atmosférico. La representación precisa de las funciones de los bosques tropicales en modelos es crucial para comprender las interacciones de este bioma con el clima.


Assuntos
Ecossistema , Raízes de Plantas , Nitrogênio , Florestas , Solo , Plantas , Água , Clima Tropical , Árvores
13.
Glob Chang Biol ; 30(7): e17420, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39044411

RESUMO

Tropical ecosystems face escalating global change. These shifts can disrupt tropical forests' carbon (C) balance and impact root dynamics. Since roots perform essential functions such as resource acquisition and tissue protection, root responses can inform about the strategies and vulnerabilities of ecosystems facing present and future global changes. However, root trait dynamics are poorly understood, especially in tropical ecosystems. We analyzed existing research on tropical root responses to key global change drivers: warming, drought, flooding, cyclones, nitrogen (N) deposition, elevated (e) CO2, and fires. Based on tree species- and community-level literature, we obtained 266 root trait observations from 93 studies across 24 tropical countries. We found differences in the proportion of root responsiveness to global change among different global change drivers but not among root categories. In particular, we observed that tropical root systems responded to warming and eCO2 by increasing root biomass in species-scale studies. Drought increased the root: shoot ratio with no change in root biomass, indicating a decline in aboveground biomass. Despite N deposition being the most studied global change driver, it had some of the most variable effects on root characteristics, with few predictable responses. Episodic disturbances such as cyclones, fires, and flooding consistently resulted in a change in root trait expressions, with cyclones and fires increasing root production, potentially due to shifts in plant community and nutrient inputs, while flooding changed plant regulatory metabolisms due to low oxygen conditions. The data available to date clearly show that tropical forest root characteristics and dynamics are responding to global change, although in ways that are not always predictable. This synthesis indicates the need for replicated studies across root characteristics at species and community scales under different global change factors.


Assuntos
Mudança Climática , Secas , Raízes de Plantas , Clima Tropical , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Árvores/crescimento & desenvolvimento , Biomassa , Nitrogênio/metabolismo , Florestas , Inundações , Incêndios
14.
BMC Cancer ; 24(1): 809, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38973003

RESUMO

BACKGROUND: Pancreatic Ductal Adenocarcinoma (PDAC) is an aggressive cancer characterized by an immunosuppressive microenvironment. Patients from specific ethnicities and population groups have poorer prognoses than others. Therefore, a better understanding of the immune landscape in such groups is necessary for disease elucidation, predicting patient outcomes and therapeutic targeting. This study investigated the expression of circulating key immune cell markers in South African PDAC patients of African ancestry. METHODS: Blood samples were obtained from a total of 6 healthy volunteers (HC), 6 Chronic Pancreatitis (CP) and 34 PDAC patients consisting of 22 resectable (RPC), 8 locally advanced (LAPC) and 4 metastatic (MPC). Real-time Quantitative Polymerase Chain reactions (RT-qPCR), Metabolomics, Enzyme-Linked Immunosorbent Assay (ELISA), Reactive Oxygen Species (ROS), and Immunophenotyping assays were conducted. Statistical analysis was conducted in R (v 4.3.2). Additional analysis of single-cell RNA data from 20 patients (16 PDAC and 4 controls) was conducted to interrogate the distribution of T-cell and Natural Killer cell populations. RESULTS: Granulocyte and neutrophil levels were significantly elevated while lymphocytes decreased with PDAC severity. The total percentages of CD3 T-cell subpopulations (helper and double negative T-cells) decreased when compared to HC. Although both NK (p = 0.014) and NKT (p < 0.001) cell levels increased as the disease progressed, their subsets: NK CD56dimCD16- (p = 0.024) and NKTs CD56+ (p = 0.008) cell levels reduced significantly. Of note is the negative association of NK CD56dimCD16- (p < 0.001) cell levels with survival time. The gene expression analyses showed no statistically significant correlation when comparing the PDAC groups with the controls. The inflammatory status of PDAC was assessed by ROS levels of serum which were elevated in CP (p = 0.025), (RPC (p = 0.003) and LAPC (p = 0.008)) while no significant change was observed in MPC, compared to the HC group. ROS was shown to be positively correlated with GlycA (R = 0.45, p = 0.0096). Single-cell analyses showed a significant difference in the ratio of NKT cells per total cell counts in LAPC (p < 0.001) and MPC (p < 0.001) groups compared with HC, confirming observations in our sample group. CONCLUSION: The expression of these immune cell markers observed in this pilot study provides insight into their potential roles in tumour progression in the patient group and suggests their potential utility in the development of immunotherapeutic strategies.


Assuntos
Carcinoma Ductal Pancreático , Progressão da Doença , Neoplasias Pancreáticas , Humanos , Carcinoma Ductal Pancreático/imunologia , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/genética , Masculino , Feminino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , África do Sul , Idoso , Adulto , Biomarcadores Tumorais/genética , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Pancreatite Crônica/imunologia , Pancreatite Crônica/genética , Pancreatite Crônica/patologia , Espécies Reativas de Oxigênio/metabolismo , Imunofenotipagem
15.
Clin J Sport Med ; 34(1): 44-51, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36853903

RESUMO

OBJECTIVE: To describe the presentation and management of lumbar bone stress injuries (LBSI), recurrent LBSI, and lumbar nonunited defects in elite Australian male and female cricket players. DESIGN: Retrospective case series. SETTING: Professional domestic and international cricket teams over 13 seasons. PARTICIPANTS: Elite Australian cricket players. INDEPENDENT VARIABLES: Symptomatic LBSI requiring time off cricket and lumbar nonunited defects, both confirmed by imaging. MAIN OUTCOME MEASURES: Incidence, presentation, history, healing, and management. RESULTS: 211 LBSI were identified at an average incidence of 5.4 per 100 players per season. LBSI were most common in male pace bowlers younger than 20 years of age (58.1 per 100 players per season), however, were also observed in older players, females, and non-pace bowlers. Recurrent LBSI accounted for 33% (27%-40%) of all LBSI. Median days to return to match availability was 182 (128-251) days for all LBSI, with a shorter time frame observed for new and less severe injuries, and male spin bowlers. Healing was demonstrated in 87% (81%-91%) of all LBSI cases. 29 nonunited defects were identified and predisposed subsequent pain, LBSI, and spondylolisthesis. CONCLUSIONS: LBSI are experienced by approximately 5.4 in every 100 elite Australian cricket players per season, with a high time cost of approximately 4 to 8 months. Nonunited defects also have a high time cost with associated subsequent lumbar spine issues. The findings of this study reinforce the importance of early detection and conservative management of LBSI, particularly for younger male pace bowlers and players with recurrent LBSI, which may be supported by MRI.


Assuntos
Traumatismos em Atletas , Lesões nas Costas , Críquete , Humanos , Masculino , Feminino , Idoso , Traumatismos em Atletas/diagnóstico por imagem , Traumatismos em Atletas/epidemiologia , Traumatismos em Atletas/terapia , Estudos Retrospectivos , Austrália/epidemiologia
16.
J Pers Assess ; 106(5): 638-650, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38271468

RESUMO

This article introduces a measure of self-condemnatory internal dialogue as an element of the relationship with the self: The Automatic Self-Recrimination Scale (ASRS). Using the construct validation approach to test construction, we describe the initial development of items and report on findings from a clinical and nonclinical sample showing the ASRS is best understood as a multidimensional measure of self-critical internal dialogue composed of one higher-order factor and four lower-order facets: Not Mattering, Self as Failure, Undeserving Self, and Loathsomeness. The overall scale and four subscales demonstrated acceptable internal consistency and test-retest reliability. Moreover, there was evidence of good convergent and incremental validity of the ASRS subscales with measures of perfectionism, self-criticism, and dysfunctional attitudes. Overall, the ASRS appears to be a reliable and valid measure of an automatic self-recriminatory internal dialogue.


Assuntos
Psicometria , Autoimagem , Humanos , Feminino , Masculino , Adulto , Reprodutibilidade dos Testes , Adulto Jovem , Adolescente , Pessoa de Meia-Idade , Inquéritos e Questionários/normas , Autoavaliação (Psicologia)
17.
J Clin Psychol ; 80(5): 945-967, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38324666

RESUMO

BACKGROUND: Meta-analyses on the relative efficacy of psychodynamic psychotherapy (PDT) and cognitive behavioral therapy (CBT) for depressive disorders are limited by heterogeneity in diagnostic samples and comparators and a lack of equivalence testing. OBJECTIVE: We addressed this through a meta-analytic test of the equivalence of manualized PDT and CBT in treating adults with depressive disorders as determined by diagnostic interviews. Sensitivity analyses evaluated the impact of pretreatment differences, mixed diagnostic samples, author allegiance, study quality, year of publication and outliers on findings. METHOD: A comprehensive literature search across multiple databases using reliable screening methods identified nine randomized controlled trials directly comparing manualized PDT and CBT for diagnosed depressive disorders in adults. Following pre-registration, we employed random effect models for our meta-analyses and two one-sided test procedures for equivalence testing. RESULTS: Independent raters determined that all studies were of adequate quality. Immediately posttreatment, depressive symptoms were statistically equivalent across PDT and CBT (k = 9; g = -0.11, 90% confidence interval [90% CI]: -0.24 to 0.02, pequivalence = .048, pNHST = .212, I2 = 32.7). At follow-up, the longest time point within a year, depressive symptoms were neither statistically equivalent nor statistically different (k = 6; g = -0.16, 90% CI: -0.31 to -0.02, pequivalence = .184, pNHST = .126, I2 = 0.00). CONCLUSION: The efficacy of manualized PDT is equal to manualized CBT immediately at posttreatment for depressive disorders in the adult general population. Nevertheless, insufficient data exists to reach a conclusion regarding equivalence at follow-up.


Assuntos
Terapia Cognitivo-Comportamental , Transtorno Depressivo , Psicoterapia Psicodinâmica , Adulto , Humanos , Psicoterapia Psicodinâmica/métodos , Terapia Cognitivo-Comportamental/métodos , Transtorno Depressivo/terapia
18.
Psychother Res ; : 1-18, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38301604

RESUMO

Objective: This randomized controlled trial investigated the efficacy of dynamic relational group therapy (DRT) relative to group psychodynamic supportive therapy (PST) in improving perfectionism-related attitudes and components of the perfectionistic self-relationship. Method: Based on a comprehensive conceptualization of perfectionism, 80 community-recruited, highly perfectionistic individuals were randomly allocated to 12 sessions of group DRT (n = 41; 5 groups) or group PST (n = 39; 5 groups). Patients completed measures of dysfunctional attitudes, self-criticism, self-esteem, and self-reassurance at pre-, mid-, and post-treatment, and six months post-treatment. Results: Multigroup latent growth curve modeling revealed significant (p < .05) decreases in dysfunctional attitudes, concern over mistakes, two types of self-criticism, and self-esteem problems, along with a significant increase in self-reassurance, from pre-treatment to six-month follow-up in both DRT and PST. Moderate-to-large between-group differences favoring DRT over PST were found for dysfunctional attitudes and self-reassurance. A majority of patients in both conditions maintained reliable improvement at six-month follow-up in dysfunctional attitudes, concern over mistakes, and self-criticism focused on inadequacy. Conclusion: Findings provide evidence for the use of psychodynamic group therapy approaches in treating perfectionism-related attitudes and self-relational elements of perfectionism, and support the relative efficacy of DRT for dysfunctional attitudes and self-reassurance.

19.
HPB (Oxford) ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39191539

RESUMO

BACKGROUND: The Delphi consensus study was carried out under the auspices of the International and Asia-Pacific Hepato-Pancreato-Biliary Associations (IHPBA-APHPBA) to develop practice guidelines for management of gallbladder cancer (GBC) globally. METHOD: GBC experts from 17 countries, spanning 6 continents, participated in a hybrid four-round Delphi consensus development process. The methodology involved email, online consultations, and in-person discussions. Sixty eight clinical questions (CQs) covering various domains related to GBC, were administered to the experts. A consensus recommendation was accepted only when endorsed by more than 75% of the participating experts. RESULTS: Out of the sixty experts invited initially to participate in the consensus process 45 (75%) responded to the invitation. The consensus was achieved in 92.6% (63/68) of the CQs. Consensus covers epidemiological aspects of GBC, early, incidental and advanced GBC management, definitions for radical GBC resections, the extent of liver resection, lymph node dissection, and definitions of borderline resectable and locally advanced GBC. CONCLUSIONS: This is the first international Delphi consensus on GBC. These recommendations provide uniform terminology and practical clinical guidelines on the current management of GBC. Unresolved contentious issues like borderline resectable/locally advanced GBC need to be addressed by future clinical studies.

20.
Ecol Lett ; 26(11): 1829-1839, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37807917

RESUMO

Tropical rainforest woody plants have been thought to have uniformly low resistance to hydraulic failure and to function near the edge of their hydraulic safety margin (HSM), making these ecosystems vulnerable to drought; however, this may not be the case. Using data collected at 30 tropical forest sites for three key traits associated with drought tolerance, we show that site-level hydraulic diversity of leaf turgor loss point, resistance to embolism (P50 ), and HSMs is high across tropical forests and largely independent of water availability. Species with high HSMs (>1 MPa) and low P50 values (< -2 MPa) are common across the wet and dry tropics. This high site-level hydraulic diversity, largely decoupled from water stress, could influence which species are favoured and become dominant under a drying climate. High hydraulic diversity could also make these ecosystems more resilient to variable rainfall regimes.


Assuntos
Ecossistema , Árvores , Clima Tropical , Florestas , Madeira , Secas , Folhas de Planta , Xilema
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA