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1.
Qual Life Res ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598132

RESUMO

PURPOSE: Patient-reported outcome measures (PROMs) are used to collect data on disease symptoms in support of clinical trial endpoints. Clinical studies can last a year or more, and the patients' adherence and response time to daily at-home questionnaires may vary significantly over time. The aim of this study was to understand patterns and changes in patients' completion of daily PROMs during longitudinal clinical studies. METHODS: Data were collected from 1342 patients randomized into three respiratory clinical trials (NCT03401229, NCT03347279, and NCT03406078). PROMs were completed by patients using electronic handheld devices that collected the starting and completion times. A Bayesian generalized linear mixed-effects model was used to identify unbiased coefficients associated with PROM adherence and response time using patient, site, and calendar features as covariates. RESULTS: Adherence decreased over time after randomization, and the rate of decrease was higher in younger patients. The 14-day pre-randomization adherence was correlated with adherence throughout the study. Patients were also more adherent during working days compared to non-working days. Oldest patients took twice as long to complete PROMs throughout the study; however, the response time for all patients decreased during the first month of the study regardless of age. Response time increased 7 days before and after the date of a scheduled clinic visit and when a patient-reported higher symptom burden. CONCLUSION: Detailed analyses of adherence and response time for daily PROMs in clinical trials can provide significant insights about trends of patient behavior in longitudinal clinical studies with high baseline adherence.

2.
Proc Biol Sci ; 291(2019): 20232258, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38531402

RESUMO

Attempts to explain the origin and diversification of vertebrates have commonly invoked the evolution of feeding ecology, contrasting the passive suspension feeding of invertebrate chordates and larval lampreys with active predation in living jawed vertebrates. Of the extinct jawless vertebrates that phylogenetically intercalate these living groups, the feeding apparatus is well-preserved only in the early diverging stem-gnathostome heterostracans. However, its anatomy remains poorly understood. Here, we use X-ray microtomography to characterize the feeding apparatus of the pteraspid heterostracan Rhinopteraspis dunensis (Roemer, 1855). The apparatus is composed of 13 plates arranged approximately bilaterally, most of which articulate from the postoral plate. Our reconstruction shows that the oral plates were capable of rotating around the transverse axis, but likely with limited movement. It also suggests the nasohypophyseal organs opened internally, into the pharynx. The functional morphology of the apparatus in Rhinopteraspis precludes all proposed interpretations of feeding except for suspension/deposit feeding and we interpret the apparatus as having served primarily to moderate the oral gape. This is consistent with evidence that at least some early jawless gnathostomes were suspension feeders and runs contrary to macroecological scenarios that envisage early vertebrate evolution as characterized by a directional trend towards increasingly active food acquisition.


Assuntos
Evolução Biológica , Fósseis , Animais , Peixes/anatomia & histologia , Vertebrados/anatomia & histologia , Arcada Osseodentária/anatomia & histologia , Filogenia
3.
Nat Ecol Evol ; 8(3): 519-535, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38216617

RESUMO

Polyploidy or whole-genome duplication (WGD) is a major event that drastically reshapes genome architecture and is often assumed to be causally associated with organismal innovations and radiations. The 2R hypothesis suggests that two WGD events (1R and 2R) occurred during early vertebrate evolution. However, the timing of the 2R event relative to the divergence of gnathostomes (jawed vertebrates) and cyclostomes (jawless hagfishes and lampreys) is unresolved and whether these WGD events underlie vertebrate phenotypic diversification remains elusive. Here we present the genome of the inshore hagfish, Eptatretus burgeri. Through comparative analysis with lamprey and gnathostome genomes, we reconstruct the early events in cyclostome genome evolution, leveraging insights into the ancestral vertebrate genome. Genome-wide synteny and phylogenetic analyses support a scenario in which 1R occurred in the vertebrate stem-lineage during the early Cambrian, and 2R occurred in the gnathostome stem-lineage, maximally in the late Cambrian-earliest Ordovician, after its divergence from cyclostomes. We find that the genome of stem-cyclostomes experienced an additional independent genome triplication. Functional genomic and morphospace analyses demonstrate that WGD events generally contribute to developmental evolution with similar changes in the regulatory genome of both vertebrate groups. However, appreciable morphological diversification occurred only in the gnathostome but not in the cyclostome lineage, calling into question the general expectation that WGDs lead to leaps of bodyplan complexity.


Assuntos
Feiticeiras (Peixe) , Animais , Filogenia , Feiticeiras (Peixe)/genética , Duplicação Gênica , Vertebrados/genética , Genoma , Lampreias/genética
4.
Nature ; 621(7980): 782-787, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37730987

RESUMO

The neurocranium is an integral part of the vertebrate head, itself a major evolutionary innovation1,2. However, its early history remains poorly understood, with great dissimilarity in form between the two living vertebrate groups: gnathostomes (jawed vertebrates) and cyclostomes (hagfishes and lampreys)2,3. The 100 Myr gap separating the Cambrian appearance of vertebrates4-6 from the earliest three-dimensionally preserved vertebrate neurocrania7 further obscures the origins of modern states. Here we use computed tomography to describe the cranial anatomy of an Ordovician stem-group gnathostome: Eriptychius americanus from the Harding Sandstone of Colorado, USA8. A fossilized head of Eriptychius preserves a symmetrical set of cartilages that we interpret as the preorbital neurocranium, enclosing the fronts of laterally placed orbits, terminally located mouth, olfactory bulbs and pineal organ. This suggests that, in the earliest gnathostomes, the neurocranium filled out the space between the dermal skeleton and brain, like in galeaspids, osteostracans and placoderms and unlike in cyclostomes2. However, these cartilages are not fused into a single neurocranial unit, suggesting that this is a derived gnathostome trait. Eriptychius fills a major temporal and phylogenetic gap in our understanding of the evolution of the gnathostome head, revealing a neurocranium with an anatomy unlike that of any previously described vertebrate.


Assuntos
Fósseis , Filogenia , Crânio , Vertebrados , Animais , Feiticeiras (Peixe)/anatomia & histologia , Imageamento Tridimensional , Lampreias/anatomia & histologia , Boca , Bulbo Olfatório , Glândula Pineal , Crânio/anatomia & histologia , Tomógrafos Computadorizados , Vertebrados/anatomia & histologia , Vertebrados/classificação , Colorado , Cartilagem/anatomia & histologia
5.
Proc Natl Acad Sci U S A ; 120(4): e2207854119, 2023 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-36649436

RESUMO

The Carboniferous (358.9 to 298.9 Ma) saw the emergence of marine ecosystems dominated by modern vertebrate groups, including abundant stem-group holocephalans (chimaeras and relatives). Compared with the handful of anatomically conservative holocephalan genera alive today-demersal durophages all-these animals were astonishingly morphologically diverse, and bizarre anatomies in groups such as iniopterygians hint at specialized ecological roles foreshadowing those of the later, suction-feeding neopterygians. However, flattened fossils usually obscure these animals' functional morphologies and how they fitted into these important early ecosystems. Here, we use three-dimensional (3D) methods to show that the musculoskeletal anatomy of the uniquely 3D-preserved iniopterygian Iniopera can be best interpreted as being similar to that of living holocephalans rather than elasmobranchs but that it was mechanically unsuited to durophagy. Rather, Iniopera had a small, anteriorly oriented mouth aperture, expandable pharynx, and strong muscular links among the pectoral girdle, neurocranium, and ventral pharynx consistent with high-performance suction feeding, something exhibited by no living holocephalan and never clearly characterized in any of the extinct members of the holocephalan stem-group. Remarkably, in adapting a distinctly holocephalan anatomy to suction feeding, Iniopera is more comparable to modern tetrapod suction feeders than to the more closely related high-performance suction-feeding elasmobranchs. This raises questions about the assumed role of durophagy in the evolution of holocephalans' distinctive anatomy and offers a rare glimpse into the breadth of ecological niches filled by holocephalans in a pre-neopterygian world.


Assuntos
Ecossistema , Crânio , Animais , Sucção , Crânio/anatomia & histologia , Vertebrados/anatomia & histologia , Peixes/anatomia & histologia , Comportamento Alimentar
6.
R Soc Open Sci ; 8(11): 210822, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34804566

RESUMO

The teeth of sharks famously form a series of transversely organized files with a conveyor-belt replacement that are borne directly on the jaw cartilages, in contrast to the dermal plate-borne dentition of bony fishes that undergoes site-specific replacement. A major obstacle in understanding how this system evolved is the poorly understood relationships of the earliest chondrichthyans and the profusion of morphologically and terminologically diverse bones, cartilages, splints and whorls that they possess. Here, we use tomographic methods to investigate mandibular structures in several early branching 'acanthodian'-grade stem-chondrichthyans. We show that the dentigerous jaw bones of disparate genera of ischnacanthids are united by a common construction, being growing bones with non-shedding dentition. Mandibular splints, which support the ventro-lateral edge of the Meckel's cartilage in some taxa, are formed from dermal bone and may be an acanthodid synapomorphy. We demonstrate that the teeth of Acanthodopsis are borne directly on the mandibular cartilage and that this taxon is deeply nested within an edentulous radiation, representing an unexpected independent origin of teeth. Many or even all of the range of unusual oral structures may be apomorphic, but they should nonetheless be considered when building hypotheses of tooth and jaw evolution, both in chondrichthyans and more broadly.

7.
J Anat ; 238(5): 1082-1105, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33415764

RESUMO

The anatomy of sharks, rays, and chimaeras (chondrichthyans) is crucial to understanding the evolution of the cranial system in vertebrates due to their position as the sister group to bony fishes (osteichthyans). Strikingly different arrangements of the head in the two constituent chondrichthyan groups-holocephalans and elasmobranchs-have played a pivotal role in the formation of evolutionary hypotheses targeting major cranial structures such as the jaws and pharynx. However, despite the advent of digital dissections as a means of easily visualizing and sharing the results of anatomical studies in three dimensions, information on the musculoskeletal systems of the chondrichthyan head remains largely limited to traditional accounts, many of which are at least a century old. Here, we use synchrotron tomographic data to carry out a digital dissection of a holocephalan and an elasmobranch widely used as model species: the elephantfish, Callorhinchus milii, and the small-spotted catshark, Scyliorhinus canicula. We describe and figure the skeletal anatomy of the head, labial, mandibular, hyoid, and branchial cartilages in both taxa as well as the muscles of the head and pharynx. In Callorhinchus, we make several new observations regarding the branchial musculature, revealing several previously unreported or ambiguously characterized muscles, likely homologous to their counterparts in the elasmobranch pharynx. We also identify a previously unreported structure linking the pharyngohyal of Callorhinchus to the neurocranium. Finally, we review what is known about the evolution of chondrichthyan cranial muscles from their fossil record and discuss the implications for muscle homology and evolution, broadly concluding that the holocephalan pharynx is likely derived from a more elasmobranch-like form which is plesiomorphic for the chondrichthyan crown group. This dataset has great potential as a resource, particularly for researchers using these model species for zoological research, functional morphologists requiring models of musculature and skeletons, as well as for palaeontologists seeking comparative models for extinct taxa.


Assuntos
Peixe Elétrico/anatomia & histologia , Cabeça/anatomia & histologia , Músculo Esquelético/anatomia & histologia , Tubarões/anatomia & histologia , Animais , Evolução Biológica , Processamento de Imagem Assistida por Computador , Filogenia
8.
Nat Ecol Evol ; 4(11): 1477-1484, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32895518

RESUMO

Endochondral bone is the main internal skeletal tissue of nearly all osteichthyans-the group comprising more than 60,000 living species of bony fishes and tetrapods. Chondrichthyans (sharks and their kin) are the living sister group of osteichthyans and have primarily cartilaginous endoskeletons, long considered the ancestral condition for all jawed vertebrates (gnathostomes). The absence of bone in modern jawless fishes and the absence of endochondral ossification in early fossil gnathostomes appear to lend support to this conclusion. Here we report the discovery of extensive endochondral bone in Minjinia turgenensis, a new genus and species of 'placoderm'-like fish from the Early Devonian (Pragian) of western Mongolia described using X-ray computed microtomography. The fossil consists of a partial skull roof and braincase with anatomical details providing strong evidence of placement in the gnathostome stem group. However, its endochondral space is filled with an extensive network of fine trabeculae resembling the endochondral bone of osteichthyans. Phylogenetic analyses place this new taxon as a proximate sister group of the gnathostome crown. These results provide direct support for theories of generalized bone loss in chondrichthyans. Furthermore, they revive theories of a phylogenetically deeper origin of endochondral bone and its absence in chondrichthyans as a secondary condition.


Assuntos
Fósseis , Arcada Osseodentária , Animais , Arcada Osseodentária/anatomia & histologia , Mongólia , Filogenia , Crânio/anatomia & histologia , Crânio/diagnóstico por imagem
9.
Nat Commun ; 10(1): 2050, 2019 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-31053719

RESUMO

The gill apparatus of gnathostomes (jawed vertebrates) is fundamental to feeding and ventilation and a focal point of classic hypotheses on the origin of jaws and paired appendages. The gill skeletons of chondrichthyans (sharks, batoids, chimaeras) have often been assumed to reflect ancestral states. However, only a handful of early chondrichthyan gill skeletons are known and palaeontological work is increasingly challenging other pre-supposed shark-like aspects of ancestral gnathostomes. Here we use computed tomography scanning to image the three-dimensionally preserved branchial apparatus in Ptomacanthus, a 415 million year old stem-chondrichthyan. Ptomacanthus had an osteichthyan-like compact pharynx with a bony operculum helping constrain the origin of an elongate elasmobranch-like pharynx to the chondrichthyan stem-group, rather than it representing an ancestral condition of the crown-group. A mixture of chondrichthyan-like and plesiomorphic pharyngeal patterning in Ptomacanthus challenges the idea that the ancestral gnathostome pharynx conformed to a morphologically complete ancestral type.


Assuntos
Evolução Biológica , Fósseis/diagnóstico por imagem , Brânquias/fisiologia , Faringe/anatomia & histologia , Tubarões/anatomia & histologia , Animais , Paleontologia , Faringe/diagnóstico por imagem , Filogenia , Tubarões/fisiologia , Esqueleto/diagnóstico por imagem , Microtomografia por Raio-X
10.
Gen Hosp Psychiatry ; 36(6): 607-12, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25052476

RESUMO

OBJECTIVE: The National Institute for Health and Care Excellence recommends the use of structured tools to improve holistic care for patients with cancer. The Distress Thermometer and Problem Checklist (DT) is commonly used for screening in physical health settings. However, it has not been integrated into the clinical pathway within specialist psycho-oncology services. We used the DT to examine the broad clinical effectiveness of psycho-oncology intervention and to ascertain factors from the DT linked to an improved outcome. We also evaluated patients' satisfaction with their care. METHOD: We asked 111 adult outpatients referred to York Psycho-Oncology Service to complete the DT at their first appointment. Individuals offered a period of psycho-oncology care re-rated their emotional distress, problems and service satisfaction on the DT at discharge. RESULTS: Median distress scores decreased significantly (from 6 to 4, Wilcoxon's z = -4.83, P < .001) indicating a large clinical effect size (Cohen's d = 1.22). Frequency of emotional problems (anxiety, depression and anger) fell significantly by 15-24% despite no significant change in patients' physical health or practical problems. Number of emotional problems was the best predictor of distress at discharge (beta = 0.468, P = .002). Satisfaction was high and correlated with lower distress scores (r = -0.42, P = .005) and fewer emotional problems (r = -0.31, P = .04) at discharge but not with number of appointments attended. Qualitative thematic analysis showed patients particularly value supportive listening and advice on coping strategies from professionals independent of their physical care. CONCLUSION: The DT is an acceptable and useful tool for enhancing the delivery of structured psycho-oncology care. It may also provide evidence to support the effectiveness of specialist psycho-oncology interventions.


Assuntos
Neoplasias/psicologia , Serviço Hospitalar de Oncologia , Satisfação do Paciente , Psicologia , Estresse Psicológico/psicologia , Escala Visual Analógica , Adulto , Institutos de Câncer , Feminino , Humanos , Masculino , Estresse Psicológico/diagnóstico , Inquéritos e Questionários
11.
J Neurosci ; 30(16): 5690-701, 2010 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-20410121

RESUMO

How seizures start is a major question in epilepsy research. Preictal EEG changes occur in both human patients and animal models, but their underlying mechanisms and relationship with seizure initiation remain unknown. Here we demonstrate the existence, in the hippocampal CA1 region, of a preictal state characterized by the progressive and global increase in neuronal activity associated with a widespread buildup of low-amplitude high-frequency activity (HFA) (>100 Hz) and reduction in system complexity. HFA is generated by the firing of neurons, mainly pyramidal cells, at much lower frequencies. Individual cycles of HFA are generated by the near-synchronous (within approximately 5 ms) firing of small numbers of pyramidal cells. The presence of HFA in the low-calcium model implicates nonsynaptic synchronization; the presence of very similar HFA in the high-potassium model shows that it does not depend on an absence of synaptic transmission. Immediately before seizure onset, CA1 is in a state of high sensitivity in which weak depolarizing or synchronizing perturbations can trigger seizures. Transition to seizure is characterized by a rapid expansion and fusion of the neuronal populations responsible for HFA, associated with a progressive slowing of HFA, leading to a single, massive, hypersynchronous cluster generating the high-amplitude low-frequency activity of the seizure.


Assuntos
Sincronização Cortical , Epilepsia/fisiopatologia , Rede Nervosa/fisiologia , Neurônios/fisiologia , Potenciais de Ação/fisiologia , Animais , Região CA1 Hipocampal/fisiologia , Epilepsia/etiologia , Masculino , Ratos , Ratos Sprague-Dawley
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