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1.
Development ; 150(6)2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36919845

RESUMO

Diverse branching forms have evolved multiple times across the tree of life to facilitate resource acquisition and exchange with the environment. In the vascular plant group, the ancestral pattern of branching involves dichotomy of a parent shoot apex to form two new daughter apices. The molecular basis of axillary branching in Arabidopsis is well understood, but few regulators of dichotomous branching are known. Through analyses of dichotomous branching in the lycophyte, Selaginella kraussiana, we identify PIN-mediated auxin transport as an ancestral branch regulator of vascular plants. We show that short-range auxin transport out of the apices promotes dichotomy and that branch dominance is globally coordinated by long-range auxin transport. Uniquely in Selaginella, angle meristems initiate at each dichotomy, and these can develop into rhizophores or branching angle shoots. We show that long-range auxin transport and a transitory drop in PIN expression are involved in angle shoot development. We conclude that PIN-mediated auxin transport is an ancestral mechanism for vascular plant branching that was independently recruited into Selaginella angle shoot development and seed plant axillary branching during evolution.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Brotos de Planta , Ácidos Indolacéticos/metabolismo , Transporte Biológico , Meristema/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas
2.
Ann Neurol ; 95(6): 1205-1219, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38501317

RESUMO

OBJECTIVE: The aim of this study was to investigate the cognitive effects of unilateral directional versus ring subthalamic nucleus deep brain stimulation (STN DBS) in patients with advanced Parkinson's disease. METHODS: We examined 31 participants who underwent unilateral STN DBS (left n = 17; right n = 14) as part of an National Institutes of Health (NIH)-sponsored randomized, double-blind, crossover study contrasting directional versus ring stimulation. All participants received unilateral DBS implants in the hemisphere more severely affected by motor parkinsonism. Measures of cognition included verbal fluency, auditory-verbal memory, and response inhibition. We used mixed linear models to contrast the effects of directional versus ring stimulation and implant hemisphere on longitudinal cognitive function. RESULTS: Crossover analyses showed no evidence for group-level changes in cognitive performance related to directional versus ring stimulation. Implant hemisphere, however, impacted cognition in several ways. Left STN participants had lower baseline verbal fluency than patients with right implants (t [20.66 = -2.50, p = 0.02]). Verbal fluency declined after left (p = 0.013) but increased after right STN DBS (p < 0.001), and response inhibition was faster following right STN DBS (p = 0.031). Regardless of hemisphere, delayed recall declined modestly over time versus baseline (p = 0.001), and immediate recall was unchanged. INTERPRETATION: Directional versus ring STN DBS did not differentially affect cognition. Similar to prior bilateral DBS studies, unilateral left stimulation worsened verbal fluency performance. In contrast, unilateral right STN surgery increased performance on verbal fluency and response inhibition tasks. Our findings raise the hypothesis that unilateral right STN DBS in selected patients with predominant right brain motor parkinsonism could mitigate declines in verbal fluency associated with the bilateral intervention. ANN NEUROL 2024;95:1205-1219.


Assuntos
Cognição , Estudos Cross-Over , Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Humanos , Estimulação Encefálica Profunda/efeitos adversos , Estimulação Encefálica Profunda/métodos , Doença de Parkinson/terapia , Doença de Parkinson/fisiopatologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Método Duplo-Cego , Cognição/fisiologia
3.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38124548

RESUMO

Why does unilateral deep brain stimulation improve motor function bilaterally? To address this clinical observation, we collected parallel neural recordings from sensorimotor cortex (SMC) and the subthalamic nucleus (STN) during repetitive ipsilateral, contralateral, and bilateral hand movements in patients with Parkinson's disease. We used a cross-validated electrode-wise encoding model to map electromyography data to the neural signals. Electrodes in the STN encoded movement at a comparable level for both hands, whereas SMC electrodes displayed a strong contralateral bias. To examine representational overlap across the two hands, we trained the model with data from one condition (contralateral hand) and used the trained weights to predict neural activity for movements produced with the other hand (ipsilateral hand). Overall, between-hand generalization was poor, and this limitation was evident in both regions. A similar method was used to probe representational overlap across different task contexts (unimanual vs. bimanual). Task context was more important for the STN compared to the SMC indicating that neural activity in the STN showed greater divergence between the unimanual and bimanual conditions. These results indicate that SMC activity is strongly lateralized and relatively context-free, whereas the STN integrates contextual information with the ongoing behavior.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Córtex Sensório-Motor , Núcleo Subtalâmico , Humanos , Núcleo Subtalâmico/fisiologia , Mãos/fisiologia , Movimento/fisiologia , Doença de Parkinson/terapia , Estimulação Encefálica Profunda/métodos
4.
Plant J ; 115(5): 1331-1344, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37243383

RESUMO

The plant-specific TOPLESS (TPL) family of transcriptional corepressors is integral to multiple angiosperm developmental processes. Despite this, we know little about TPL function in other plants. To address this gap, we investigated the roles TPL plays in the bryophyte Physcomitrium patens, which diverged from angiosperms approximately 0.5 billion years ago. Although complete loss of PpTPL function is lethal, transgenic lines with reduced PpTPL activity revealed that PpTPLs are essential for two fundamental developmental switches in this plant: the transitions from basal photosynthetic filaments (chloronemata) to specialised foraging filaments (caulonemata) and from two-dimensional (2D) to three-dimensional (3D) growth. Using a transcriptomics approach, we integrated PpTPL into the regulatory network governing 3D growth and we propose that PpTPLs represent another important class of regulators that are essential for the 2D-to-3D developmental switch. Transcriptomics also revealed a previously unknown role for PpTPL in the regulation of flavonoids. Intriguingly, 3D growth and the formation of caulonemata were crucial innovations that facilitated the colonisation of land by plants, a major transformative event in the history of life on Earth. We conclude that TPL, which existed before the land plants, was co-opted into new developmental pathways, enabling phytoterrestrialisation and the evolution of land plants.


Assuntos
Bryopsida , Plantas , Proteínas Correpressoras/metabolismo , Plantas/metabolismo , Fatores de Transcrição/metabolismo , Bryopsida/metabolismo , Regulação da Expressão Gênica de Plantas
5.
Proteins ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747689

RESUMO

Structures at serine-proline sites in proteins were analyzed using a combination of peptide synthesis with structural methods and bioinformatics analysis of the PDB. Dipeptides were synthesized with the proline derivative (2S,4S)-(4-iodophenyl)hydroxyproline [hyp(4-I-Ph)]. The crystal structure of Boc-Ser-hyp(4-I-Ph)-OMe had two molecules in the unit cell. One molecule exhibited cis-proline and a type VIa2 ß-turn (BcisD). The cis-proline conformation was stabilized by a C-H/O interaction between Pro C-Hα and the Ser side-chain oxygen. NMR data were consistent with stabilization of cis-proline by a C-H/O interaction in solution. The other crystallographically observed molecule had trans-Pro and both residues in the PPII conformation. Two conformations were observed in the crystal structure of Ac-Ser-hyp(4-I-Ph)-OMe, with Ser adopting PPII in one and the ß conformation in the other, each with Pro in the δ conformation and trans-Pro. Structures at Ser-Pro sequences were further examined via bioinformatics analysis of the PDB and via DFT calculations. Ser-Pro versus Ala-Pro sequences were compared to identify bases for Ser stabilization of local structures. C-H/O interactions between the Ser side-chain Oγ and Pro C-Hα were observed in 45% of structures with Ser-cis-Pro in the PDB, with nearly all Ser-cis-Pro structures adopting a type VI ß-turn. 53% of Ser-trans-Pro sequences exhibited main-chain COi•••HNi+3 or COi•••HNi+4 hydrogen bonds, with Ser as the i residue and Pro as the i + 1 residue. These structures were overwhelmingly either type I ß-turns or N-terminal capping motifs on α-helices or 310-helices. These results indicate that Ser-Pro sequences are particularly potent in favoring these structures. In each, Ser is in either the PPII or ß conformation, with the Ser Oγ capable of engaging in a hydrogen bond with the amide N-H of the i + 2 (type I ß-turn or 310-helix; Ser χ1 t) or i + 3 (α-helix; Ser χ1 g+) residue. Non-proline cis amide bonds can also be stabilized by C-H/O interactions.

6.
J Urol ; : 101097JU0000000000004124, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935793

RESUMO

PURPOSE: AUA guidelines prioritize nephron sparing in patients with preexisting chronic kidney disease (CKD). However, few studies analyze long-term renal function in patients with preoperative severe CKD who undergo extirpative renal surgery. Herein, we compare the hazard of progression to end-stage kidney disease (ESKD) following partial nephrectomy (PN) and radical nephrectomy (RN) among patients with preoperative severe CKD. MATERIALS AND METHODS: Patients with stage 4 CKD who underwent PN or RN from 1970 to 2018 were identified. A multivariable Fine-Gray subdistribution hazard model was employed to assess associations with progression to ESKD accounting for the competing risk of death. RESULTS: A total of 186 patients with stage 4 CKD underwent PN (n = 71; 38%) or RN (n = 115; 62%) for renal neoplasms with median follow-up of 6.9 years (interquartile range 3.8-14.1). On multivariable analyses adjusting for competing risk of death, the subdistribution hazard ratio (SHR) for older age at surgery (SHR for 5-year increase 0.81; 95% CI 0.73-0.91; P < .001) and higher preoperative estimated glomerular filtration rate (SHR for 5-unit increase 0.63; 95% CI 0.47-0.84; P = .002) was associated with lower hazard of progression to ESKD. There was no significant difference in hazard of ESKD between PN and RN (SHR 0.82; 95% CI 0.50-1.33; P = .4). CONCLUSIONS: Among patients with preoperative severe CKD, higher preoperative estimated glomerular filtration rate was associated with lower hazard of progression to ESKD after extirpative surgery for renal neoplasms. We did not observe a significant difference in overall hazard for developing ESKD between PN and RN.

7.
Qual Life Res ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39023734

RESUMO

PURPOSE: We provide an initial description and validation of some public domain patient-reported outcome (PRO) items to assess cancer symptom burden to address immediate barriers to symptom assessment use in clinical practice and facilitate future research. METHODS: We created the Open Symptom Framework (OSF), a flexible tool for clinical cancer-related symptom assessment. The items comprise six components: recall period, concept, symptom, qualifier(s), a definition, and a 5-point Likert-type response. We recruited patients receiving cancer therapy in the United States and United Kingdom. We assessed external construct validity by comparing OSF scores to the PRO-CTCAE measure and assessed reliability, scalability, dimensionality, and item ordering within a non-parametric item response theory framework. We tested differential item functioning for country, age, gender, and level of education. RESULTS: We developed a framework alongside clinical and psychometric experts and debrieifed with 10 patients. For validation, we recruited 331patients. All items correlated with the PRO-CTCAE equivalents (r = 0.55-0.96, all p < 0.01). Mokken analysis confirmed the scalability and unidimensionality of all symptom scales with multiple items at the scale (Ho = 0.61-0.75) and item level (Hi = 0.60-0.76). Items are interpreted consistently between demographic groups (Crit = 0 for all groups). CONCLUSION: The public domain OSF has excellent psychometric properties including face, content, and criterion validity and can facilitate the development of flexible, robust measurements to fulfil stakeholder need. The OSF was designed specifically to support clinical assessment but will function well for research. Further work is planned to increase the number of symptoms and number of questions per symptom within the framework.

8.
Med Educ ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639098

RESUMO

INTRODUCTION: In the past year, the use of large language models (LLMs) has generated significant interest and excitement because of their potential to revolutionise various fields, including medical education for aspiring physicians. Although medical students undergo a demanding educational process to become competent health care professionals, the emergence of LLMs presents a promising solution to challenges like information overload, time constraints and pressure on clinical educators. However, integrating LLMs into medical education raises critical concerns and challenges for educators, professionals and students. This systematic review aims to explore LLM applications in medical education, specifically their impact on medical students' learning experiences. METHODS: A systematic search was performed in PubMed, Web of Science and Embase for articles discussing the applications of LLMs in medical education using selected keywords related to LLMs and medical education, from the time of ChatGPT's debut until February 2024. Only articles available in full text or English were reviewed. The credibility of each study was critically appraised by two independent reviewers. RESULTS: The systematic review identified 166 studies, of which 40 were found by review to be relevant to the study. Among the 40 relevant studies, key themes included LLM capabilities, benefits such as personalised learning and challenges regarding content accuracy. Importantly, 42.5% of these studies specifically evaluated LLMs in a novel way, including ChatGPT, in contexts such as medical exams and clinical/biomedical information, highlighting their potential in replicating human-level performance in medical knowledge. The remaining studies broadly discussed the prospective role of LLMs in medical education, reflecting a keen interest in their future potential despite current constraints. CONCLUSIONS: The responsible implementation of LLMs in medical education offers a promising opportunity to enhance learning experiences. However, ensuring information accuracy, emphasising skill-building and maintaining ethical safeguards are crucial. Continuous critical evaluation and interdisciplinary collaboration are essential for the appropriate integration of LLMs in medical education.

9.
Sensors (Basel) ; 24(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38610427

RESUMO

Flexibility in performing various movements like standing, walking, and turning is crucial for navigating dynamic environments in daily life. Individuals with essential tremor often experience movement difficulties that can affect these postural transitions, limiting mobility and independence. Yet, little research has examined the performance of postural transitions in people with essential tremor. Therefore, we assessed postural transition performance using two versions of the timed up and go test: the standard version and a more complex water-carry version. We examined the total duration of the standard and water-carry timed up and go in 15 people with and 15 people without essential tremor. We also compared the time taken for each phase (sit-to-stand phase, straight-line walk phase, stand-to-sit phase) and the turning velocity between groups. Our findings revealed decreased performance across all phases of standard and water-carry timed up and go assessments. Further, both ET and non-ET groups exhibited reduced performance during the water-carry timed up and go compared to the standard timed up and go. Evaluating specific phases of the timed up and go offers valuable insights into functional movement performance in essential tremor, permitting more tailored therapeutic interventions to improve functional performance during activities of daily living.


Assuntos
Tremor Essencial , Humanos , Atividades Cotidianas , Equilíbrio Postural , Estudos de Tempo e Movimento , Água
10.
Molecules ; 29(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38893352

RESUMO

Molecular probes with the ability to differentiate between subcellular variations in acidity levels remain important for the investigation of dynamic cellular processes and functions. In this context, a series of cyclic peptide and PEG bio-conjugated dual near-infrared emissive BF2-azadipyrromethene fluorophores with maxima emissions at 720 nm (at pH > 6) and 790 nm (at pH < 5) have been developed and their aqueous solution photophysical properties determined. Their inter-converting emissions and fluorescence lifetime characteristics were exploited to track their spatial and temporal progression from first contact with the plasma membrane to subcellular locales to their release within extracellular vesicles. A pH-dependent reversible phenolate/phenol interconversion on the fluorophore controlled the dynamic changes in dual emission responses and corresponding lifetime changes. Live-cell confocal microscopy experiments in the metastatic breast cancer cell line MDA-MB-231 confirmed the usability of the dual emissive properties for imaging over prolonged periods. All three derivatives performed as probes capable of real-time continuous imaging of fundamental cellular processes such as plasma membrane interaction, tracking endocytosis, lysosomal/large acidic vesicle accumulation, and efflux within extracellular vesicles without perturbing cellular function. Furthermore, fluorescence lifetime imaging microscopy provided valuable insights regarding fluorophore progression through intracellular microenvironments over time. Overall, the unique photophysical properties of these fluorophores show excellent potential for their use as information-rich probes.


Assuntos
Membrana Celular , Corantes Fluorescentes , Humanos , Corantes Fluorescentes/química , Membrana Celular/metabolismo , Membrana Celular/química , Linhagem Celular Tumoral , Microscopia Confocal , Concentração de Íons de Hidrogênio , Microscopia de Fluorescência/métodos , Endocitose , Peptídeos Cíclicos/química
11.
Plant Physiol ; 190(1): 100-112, 2022 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-35771646

RESUMO

Land plant life cycles are separated into distinct haploid gametophyte and diploid sporophyte stages. Indeterminate apical growth evolved independently in bryophyte (moss, liverwort, and hornwort) and fern gametophytes, and tracheophyte (vascular plant) sporophytes. The extent to which apical growth in tracheophytes co-opted conserved gametophytic gene networks, or exploited ancestral sporophytic networks, is a long-standing question in plant evolution. The recent phylogenetic confirmation of bryophytes and tracheophytes as sister groups has led to a reassessment of the nature of the ancestral land plant. Here, we review developmental genetic studies of apical regulators and speculate on their likely evolutionary history.


Assuntos
Briófitas , Embriófitas , Briófitas/genética , Embriófitas/genética , Células Germinativas Vegetais , Filogenia , Plantas/genética
12.
Hum Reprod ; 38(3): 430-443, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36637254

RESUMO

STUDY QUESTION: Is it possible to design an ART Treatment Planning and Continuation Intervention (TPCI) that is considered acceptable and feasible to patients and healthcare professionals (HCPs)? SUMMARY ANSWER: HCPs and patients responded positively to the TPCI prototype and perceived it as an acceptable intervention to support patients to stay engaged with planned treatment, but some concerns were raised about the feasibility of using it in practice. WHAT IS KNOWN ALREADY: People discontinue ART due to its psychological burden. Digital tools to support people undergoing ART are available but typically focus only on practical support rather than psychological support. Research about treatment continuation and multi-cycle planning indicates that cognitive factors (expectations, intentions, efficacy beliefs) should be targets of interventions designed to help patients engage with and continue treatment to meet their personal treatment plans and goals. However, it is not known whether this form of psychological support would be acceptable for HCPs and patients or feasible to implement in practice. STUDY DESIGN, SIZE, DURATION: Qualitative cognitive interviews with HCPs and patients (May 2021). Patients were eligible if they had had a consultation to start a first/repeat stimulated IVF/ICSI cycle in the 8 weeks prior to recruitment, were aged 18 or older (upper age limit of 42 years for women) and fluent in English. Eligible HCPs were those employed by a fertility clinic who were responsible for delivering treatment planning consultations to patients. PARTICIPANTS/MATERIALS, SETTING, METHODS: HCPs and patients were asked to think aloud while being exposed to and exploring the TPCI in one-to-one online cognitive interviews. The TPCI was designed to reduce treatment discontinuation via cognitive factors namely formation and maintenance of multi-cycle ART intentions and efficiency of decision-making during treatment, and continuation of treatment after an unsuccessful cycle (when recommended). To impact cognitive factors the TPCI comprised of two components: an expectation management and reasoning checklist for HCPs to use during planning consultations (TPCI Checklist) and a multi-feature cognitive support mobile application (TPCI App) for patients to use prior to and during treatment. After participants thought aloud while being exposed to the TPCI prototype (both components) they were asked open questions concerning their perceptions of the core components and activities on eight acceptability dimensions (e.g. acceptability, demand, integration). Interviews lasted between 40 and 90 min, were recorded, transcribed verbatim and analysed using thematic analysis. MAIN RESULTS AND THE ROLE OF CHANCE: Thirteen HCPs and 13 patients participated in 25 online interviews. Thematic analysis using inductive and deductive coding generated 180 codes, grouped into 22 categories and synthesized into 9 themes. The themes showed that HCPs and patients provided positive feedback about the TPCI, perceiving it as a needed, acceptable and potentially effective way to forewarn patients of the possible need for multiple cycles, to provide patients with a sense of patient-clinic collaboration and support, and to bolster treatment intentions, all of which were perceived to contribute to reduced treatment discontinuation. HCPs perceived implementation of the TPCI Checklist to be challenging in its current length due to time pressures and clinic workload. Suggestions for enhancing the TPCI Checklist and App were provided, but none required critical changes to its core components or activities. LIMITATIONS, REASONS FOR CAUTION: All patients were women recruited from social media websites, mainly associated with patient support groups, who may be highly committed to their fertility treatment. HCPs were predominantly from private fertility clinics. WIDER IMPLICATIONS OF THE FINDINGS: The findings suggest there is demand for digital support geared towards motivational aspects of undergoing ART. The TPCI is an acceptable support tool to meet that need according to HCPs responsible for delivering planning consultations and patients undergoing fertility treatment. Future research is needed to develop the prototype and examine the feasibility of implementation of the TPCI in clinics. STUDY FUNDING/COMPETING INTEREST(S): This research was financially supported by Merck Serono Ltd, an affiliate of Merck KGaA, Darmstadt, Germany. 'Merck KGaA, Darmstadt, Germany reviewed the manuscript for medical accuracy only before journal submission. The authors are fully responsible for the content of this manuscript, and the views and opinions described in the publication reflect solely those of the authors' J.B. reports personal fees from Merck KGaA, Darmstadt, Germany, Merck AB an affiliate of Merck KGaA, Darmstadt Germany, Theramex, Organon JJC, Ferring Pharmaceuticals A/S, research grant from Merck Serono Ltd, grants from ESHRE outside the submitted work and that she is co-developer of Fertility Quality of Life (FertiQoL) and MediEmo app. S.G. reports consultancy fees from TMRW Life Sciences and Ferring Pharmaceuticals A/S, speaker fees from Access Fertility, SONA-Pharm LLC, Meridiano Congress International and Gedeon Richter. C.H. declares no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Fertilidade , Qualidade de Vida , Humanos , Feminino , Masculino , Estudos de Viabilidade , Atenção à Saúde , Preparações Farmacêuticas
13.
Public Health ; 214: 1-9, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36417813

RESUMO

OBJECTIVES: Insufficient physical activity (PA) and prolonged sitting time (ST) increase the risk of chronic disease and mortality. Caring for young children can potentially impact maternal PA and sedentary behaviours. The aims of this study were to explore the levels of PA and ST in women with young children (infants, toddlers and preschoolers) and sociodemographic and behavioural factors associated with these. STUDY DESIGN: This was a population-based cross-sectional study. METHODS: Survey 5 data collected in 2009 (n = 4290) of the 1973-1978 birth cohort of the Australian Longitudinal Study on Women's Health were used. Multiple linear and logistic regression models were used to examine associations. RESULTS: In adjusted models, compared with women with preschoolers, women whose youngest child was an infant aged 0-6 months, aged >6-12 months or toddler had lower PA (-321.3 MET.min/week [95% confidence interval (CI) -416.2, -226.4], -147.9 MET.min/week [95% CI -237.6, -58.1] and -106.4 MET.min/week [95% CI -172.3, -40.5]). ST was higher in women whose youngest child was an infant aged 0-6 months (0.48 h/day; 95% CI 0.19, 0.77) but lower with infants aged >6-12 months (-0.33 h/day; 95% CI -0.60, -0.05) and toddlers (-0.40 h/day; 95% CI -0.60, -0.20) than in those with preschoolers. The findings were similar in the logistic model. Sociodemographic and behavioural factors such as occupation and marital status also influenced PA and ST. CONCLUSIONS: Women with infants and toddlers have lower PA than women with preschoolers. Women are more likely to sit more in the first 6 months after childbirth. These findings can inform resources and intervention development to improve activity levels in women with young children through consideration of the age of the youngest child, sociodemographic and behavioural factors.


Assuntos
Exercício Físico , Postura Sentada , Humanos , Lactente , Feminino , Pré-Escolar , Estudos Transversais , Estudos Longitudinais , Austrália
14.
J Digit Imaging ; 36(4): 1770-1781, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36932251

RESUMO

The aim of this study is to investigate the use of an exponential-plateau model to determine the required training dataset size that yields the maximum medical image segmentation performance. CT and MR images of patients with renal tumors acquired between 1997 and 2017 were retrospectively collected from our nephrectomy registry. Modality-based datasets of 50, 100, 150, 200, 250, and 300 images were assembled to train models with an 80-20 training-validation split evaluated against 50 randomly held out test set images. A third experiment using the KiTS21 dataset was also used to explore the effects of different model architectures. Exponential-plateau models were used to establish the relationship of dataset size to model generalizability performance. For segmenting non-neoplastic kidney regions on CT and MR imaging, our model yielded test Dice score plateaus of [Formula: see text] and [Formula: see text] with the number of training-validation images needed to reach the plateaus of 54 and 122, respectively. For segmenting CT and MR tumor regions, we modeled a test Dice score plateau of [Formula: see text] and [Formula: see text], with 125 and 389 training-validation images needed to reach the plateaus. For the KiTS21 dataset, the best Dice score plateaus for nn-UNet 2D and 3D architectures were [Formula: see text] and [Formula: see text] with number to reach performance plateau of 177 and 440. Our research validates that differing imaging modalities, target structures, and model architectures all affect the amount of training images required to reach a performance plateau. The modeling approach we developed will help future researchers determine for their experiments when additional training-validation images will likely not further improve model performance.


Assuntos
Processamento de Imagem Assistida por Computador , Neoplasias Renais , Humanos , Processamento de Imagem Assistida por Computador/métodos , Estudos Retrospectivos , Redes Neurais de Computação , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X , Neoplasias Renais/diagnóstico por imagem
15.
J Neurosci ; 41(19): 4253-4261, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33785642

RESUMO

Sleep spindles are intermittent bursts of 11-15 Hz EEG waves that occur during non-rapid eye movement sleep. Spindles are believed to help maintain sleep and to play a role in sleep-dependent memory consolidation. Here we applied an automated sleep spindle detection program to our large longitudinal sleep EEG dataset (98 human subjects, 6-18 years old, >2000 uninterrupted nights) to evaluate maturational trends in spindle wave frequency, density, amplitude, and duration. This large dataset enabled us to apply nonlinear as well as linear age models, thereby extending the findings of prior cross-sectional studies that used linear models. We found that spindle wave frequency increased with remarkable linearity across the age range. Central spindle density increased nonlinearly to a peak at age 15.1 years. Central spindle wave amplitude declined in a sigmoidal pattern with the age of fastest decline at 13.5 years. Spindle duration decreased linearly with age. Of the four measures, only spindle amplitude showed a sex difference in dynamics such that the age of most rapid decline in females preceded that in males by 1.4 years. This amplitude pattern, including the sex difference in timing, paralleled the maturational pattern for δ (1-4 Hz) wave power. We interpret these age-related changes in spindle characteristics as indicators of maturation of thalamocortical circuits and changes in sleep depth. These robust age-effects could facilitate the search for cognitive-behavioral correlates of spindle waveforms and might also help guide basic research on EEG mechanisms and postnatal brain maturation.SIGNIFICANCE STATEMENT The brain reorganization of adolescence produces massive changes in sleep EEG. These changes include the morphology and abundance of sleep spindles, an EEG marker of non-rapid eye movement sleep believed to reflect offline memory processes and/or protection of the sleep state. We analyzed >2000 nights of longitudinal sleep EEG from 98 subjects (age 6-18 years old) to investigate maturational changes in spindle amplitude, frequency, density, and duration. The large dataset enabled us to detect nonlinear as well as linear age changes. All measures showed robust age effects that we hypothesize reflect the maturation of thalamocortical circuits and decreasing sleep depth. These findings could guide further research into the cognitive-behavioral correlates of sleep spindles and their underlying brain mechanisms.


Assuntos
Envelhecimento/fisiologia , Fases do Sono/fisiologia , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Eletroencefalografia , Feminino , Humanos , Modelos Lineares , Estudos Longitudinais , Masculino , Consolidação da Memória , Polissonografia , Caracteres Sexuais
16.
Chembiochem ; 23(3): e202100559, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-34788501

RESUMO

The members of the infant microbiome are governed by feeding method (breastmilk vs. formula). Regardless of the source of nutrition, a competitive growth advantage can be provided to commensals through prebiotics - either human milk oligosaccharides (HMOs) or plant oligosaccharides that are supplemented into formula. To characterize how prebiotics modulate commensal - pathogen interactions, we have designed and studied a minimal microbiome where a pathogen, Streptococcus agalactiae engages with a commensal, Streptococcus salivarius. We discovered that while S. agalactiae suppresses the growth of S. salivarius via increased lactic acid production, galacto-oligosaccharides (GOS) supplementation reverses the effect. This result has major implications in characterizing how single species survive in the gut, what niche they occupy, and how they engage with other community members.


Assuntos
Oligossacarídeos/metabolismo , Prebióticos , Streptococcus agalactiae/metabolismo , Streptococcus salivarius/metabolismo , Suplementos Nutricionais , Microbioma Gastrointestinal , Humanos , Ácido Láctico/biossíntese , Ácido Láctico/química , Leite Humano/química , Oligossacarídeos/administração & dosagem , Prebióticos/administração & dosagem
17.
New Phytol ; 234(1): 149-163, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35032334

RESUMO

The CLAVATA pathway is a key regulator of stem cell function in the multicellular shoot tips of Arabidopsis, where it acts via the WUSCHEL transcription factor to modulate hormone homeostasis. Broad-scale evolutionary comparisons have shown that CLAVATA is a conserved regulator of land plant stem cell function, but CLAVATA acts independently of WUSCHEL-like (WOX) proteins in bryophytes. The relationship between CLAVATA, hormone homeostasis and the evolution of land plant stem cell functions is unknown. Here we show that in the moss, Physcomitrella (Physcomitrium patens), CLAVATA affects stem cell activity by modulating hormone homeostasis. CLAVATA pathway genes are expressed in the tip cells of filamentous tissues, regulating cell identity, filament branching, plant spread and auxin synthesis. The receptor-like kinase PpRPK2 plays the major role, and Pprpk2 mutants have abnormal responses to cytokinin, auxin and auxin transport inhibition, and show reduced expression of PIN auxin transporters. We propose a model whereby PpRPK2 modulates auxin gradients in filaments to determine stem cell identity and overall plant form. Our data indicate that CLAVATA-mediated auxin homeostasis is a fundamental property of plant stem cell function, probably exhibited by the last shared common ancestor of land plants.


Assuntos
Proteínas de Arabidopsis , Briófitas , Bryopsida , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Briófitas/metabolismo , Bryopsida/genética , Bryopsida/metabolismo , Regulação da Expressão Gênica de Plantas , Homeostase , Ácidos Indolacéticos/metabolismo , Células-Tronco/metabolismo
18.
Hum Reprod ; 37(3): 488-498, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35040994

RESUMO

STUDY QUESTION: What are patients' and fertility staff views of talking about possible IVF/ICSI failure and need for multiple cycles in treatment planning? SUMMARY ANSWER: Healthcare professionals (HCPs) typically plan treatment on a cycle-by-cycle basis but HCPs and patients see benefits in talking about possible IVF/ICSI failure and the consequent need for multiple cycles to better prepare patients for this possibility, to support them through treatment challenges and to foster a sense of collaboration with the clinic in achieving the shared goal of treatment success. WHAT IS KNOWN ALREADY: Many patients need more than one round of IVF/ICSI stimulation to achieve their parenthood goals. About 60% of patients are willing to plan for multiple cycles of treatment in advance of treatment engagement. However, it is not clear how patients are informed about the high possibility of failure and the subsequent need for multiple cycles during their treatment planning consultations, and how approaches could be optimized. STUDY DESIGN, SIZE, DURATION: Qualitative focus groups with HCPs working at fertility clinics, patient advocates employed by patient charities (April 2020) and patients (July and August 2020). Patients were eligible if they had had a consultation to start a first/repeat stimulated IVF/ICSI cycle in the 8 weeks prior to participation, were aged 18 or older (upper age limit of 42 years for women), in heterosexual relationships and fluent in English. Eligible HCPs and patient advocates were those employed at a fertility clinic or charity, respectively. PARTICIPANTS/MATERIALS, SETTINGS, METHOD: Focus group topic guides progressed from general questions about fertility consultations to if and how the possibility of treatment failure and need for multiple cycles was introduced and discussed in (attended/own) clinics. After, preferences regarding planning IVF/ICSI on a multi-cycle or cycle-by-cycle basis were explored. Focus groups were recorded, and recordings transcribed and analysed using framework analysis to identify shared, unique and incongruent themes across participant groups. MAIN RESULTS AND THE ROLE OF CHANCE: Twelve HCPs, 2 patient advocates and 10 patients participated in six semi-structured online focus group discussions. All patients were childless and had been trying to conceive for ∼3 years. Framework analysis generated four themes and one meta-theme across participant groups. The meta-theme showed planning IVF on a cycle-by-cycle basis is the norm at clinics and that this affects how treatment is planned and the acceptability of a shift towards planning for multiple cycles, which was perceived as beneficial despite some apprehension. The four themes were: (i) heterogeneity in information provision during treatment planning; (ii) the need for improved HCP-patient collaboration; (iii) the need to temper optimism about treatment success; and (iv) apprehension, benefits and preferences regarding multi-cycle planning. LIMITATIONS, REASONS FOR CAUTION: Most patients were women from private fertility clinics with no previous treatment experience recruited from social media websites, mainly associated with patient support groups. Similarly, most HCPs were women from private fertility clinics. WIDER IMPLICATIONS OF THE FINDINGS: The findings suggest that shifting from cycle-by-cycle to multi-cycle approaches in IVF planning is possible. Achieving this shift, like other shifts in IVF (e.g. single embryo transfer), is likely to require collaboration among all stakeholders (e.g. users, staff, policymakers, regulators) to ensure that costs and benefits are balanced through using appropriate benchmarks, avoiding deflating optimism, fostering a sense of collaboration and supporting patients through challenges of multi-cycle IVF. STUDY FUNDING/COMPETING INTEREST(S): This research is funded by an Investigator-Sponsor Noninterventional Study from Merck Serono Ltd (MS200059_0010), an affiliate of Merck KGaA, Darmstadt, Germany. 'Merck KGaA, Darmstadt, Germany reviewed the manuscript for medical accuracy only before journal submission. The Authors are fully responsible for the content of this manuscript, and the views and opinions described in the publication reflect solely those of the authors'. Prof. J.B. reports personal fees from Merck KGaA, Darmstadt, Germany, Merck AB an affiliate of Merck KGaA, Darmstadt Germany, Theramex, Ferring Pharmaceuticals A/S, grant from Merck Serono Ltd, outside the submitted work and that she is co-developer of Fertility Quality of Life (FertiQoL) and MediEmo app. Dr S.G. reports consultancy fees from Ferring Pharmaceuticals A/S, Access Fertility and SONA-Pharm LLC, and grants from Merck Serono Ltd, an affiliate of Merck KGaA, Darmstadt, Germany. Dr C.H. declares no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Coeficiente de Natalidade , Injeções de Esperma Intracitoplásmicas , Atenção à Saúde , Feminino , Fertilização in vitro , Humanos , Masculino , Qualidade de Vida
19.
Hum Reprod ; 37(5): 1007-1017, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35348672

RESUMO

STUDY QUESTION: Is it possible to develop a patient smartphone application for medically assisted reproduction (MAR) that is acceptable to patients and fertility staff? SUMMARY ANSWER: Staff and patients responded positively to the MediEmo smartphone application, perceiving it to be acceptable and feasible to implement in a busy clinic. WHAT IS KNOWN ALREADY: Digital tools are increasingly popular to provide practical, administrative and psychological support alongside medical treatments. Apps and other digital tools have been developed for use alongside MAR but there is very limited research on the development or acceptability and feasibility of these tools. STUDY DESIGN, SIZE, DURATION: Mixed methods research. This article outlines the development phase of the MediEmo smartphone app, which was guided by the Medical Research Council development framework for complex interventions. The resulting MediEmo app was then implemented into a single centre for MAR in the UK, acceptability evaluated and feasibility explored among 1106 potential participants undertaking IVF cycles. PARTICIPANTS/MATERIALS, SETTING, METHODS: Consultation and data collection took part at a single mid-sized urban fertility clinic. Development of the MediEmo smartphone application took place during 2013 to 2017. Implementation of the MediEmo took place from June 2017 to September 2020. The MediEmo app comprises three functions (six features) namely medication management (medication timeline, messaging), mood management (emotional tracking, coping support) and functional support (frequently asked questions, symptom checker). Data on age, fertility diagnosis, anti-Müllerian hormone level were collected about the users of the MediEmo in addition to MediEmo usage data and attitudes towards the MediEmo smartphone application. MAIN RESULTS AND THE ROLE OF CHANCE: Informed by the developmental process described, MediEmo is an app combining patient medication diary management and ease of integration into clinic systems with emotional support, emotional tracking and data capture. This study demonstrates acceptability and feasibility of MediEmo, with good uptake (79.8%), mood data sensitivity and reliability and positive feedback. LIMITATIONS, REASONS FOR CAUTION: Single centre, small number of users in questionnaire studies. WIDER IMPLICATIONS OF THE FINDINGS: The findings suggest smartphone apps can contribute to fertility care and that patient engagement is high. Evaluation of any apps introduced into clinical pathways should be encouraged to promote development of the most useful digital tools for fertility patients. STUDY FUNDING/COMPETING INTEREST(S): This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector. Outside of the submitted work, J.B. reports personal speaker fees from Merck KGaA, Darmstadt, Germany, Merck AB an affiliate of Merck KGaA, Darmstadt Germany, Theramex, MedThink China, Ferring Pharmaceuticals A/S, grant from Merck Serono Ltd, outside the submitted work and that she is co-developer of Fertility Quality of Life (FertiQoL) and MediEmo app; N.M and C.Y are minority shareholders and J.B.'s University (Cardiff University) owns one third of shares. None of the shareholders benefitted financially from MediEmo. I.R., C.H. and K.Y.B.N. declare no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Aplicativos Móveis , Estudos de Viabilidade , Feminino , Humanos , Qualidade de Vida , Reprodutibilidade dos Testes , Reprodução
20.
Mov Disord ; 37(8): 1683-1692, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35702056

RESUMO

BACKGROUND: Dystonia is an understudied motor feature of Parkinson's disease (PD). Although considerable efforts have focused on brain oscillations related to the cardinal symptoms of PD, whether dystonia is associated with specific electrophysiological features is unclear. OBJECTIVE: The objective of this study was to investigate subcortical and cortical field potentials at rest and during contralateral hand and foot movements in patients with PD with and without dystonia. METHODS: We examined the prevalence and distribution of dystonia in patients with PD undergoing deep brain stimulation surgery.  During surgery, we recorded intracranial electrophysiology from the motor cortex and directional electrodes in the subthalamic nucleus (STN) both at rest and during self-paced repetitive contralateral hand and foot movements. Wavelet transforms and mixed models characterized changes in spectral content in patients with and without dystonia. RESULTS: Dystonia was highly prevalent at enrollment (61%) and occurred most commonly in the foot. Regardless of dystonia status, cortical recordings display beta (13-30 Hz) desynchronization during movements versus rest, while STN signals show increased power in low frequencies (6.0 ± 3.3 and 4.2 ± 2.9 Hz peak frequencies for hand and foot movements, respectively). Patients with PD with dystonia during deep brain stimulation surgery displayed greater M1 beta power at rest and STN low-frequency power during movements versus those without dystonia. CONCLUSIONS: Spectral power in motor cortex and STN field potentials differs markedly during repetitive limb movements, with cortical beta desynchronization and subcortical low-frequency synchronization, especially in patients with PD with dystonia. Greater knowledge on field potential dynamics in human motor circuits can inform dystonia pathophysiology in PD and guide novel approaches to therapy. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Estimulação Encefálica Profunda , Distonia , Distúrbios Distônicos , Doença de Parkinson , Núcleo Subtalâmico , Distonia/etiologia , Humanos , Núcleo Subtalâmico/fisiologia
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