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1.
Nature ; 588(7838): 445-449, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33299179

RESUMO

Pterosaurs were the first vertebrates to evolve powered flight1 and comprised one of the main evolutionary radiations in terrestrial ecosystems of the Mesozoic era (approximately 252-66 million years ago), but their origin has remained an unresolved enigma in palaeontology since the nineteenth century2-4. These flying reptiles have been hypothesized to be the close relatives of a wide variety of reptilian clades, including dinosaur relatives2-8, and there is still a major morphological gap between those forms and the oldest, unambiguous pterosaurs from the Upper Triassic series. Here, using recent discoveries of well-preserved cranial remains, microcomputed tomography scans of fragile skull bones (jaws, skull roofs and braincases) and reliably associated postcrania, we demonstrate that lagerpetids-a group of cursorial, non-volant dinosaur precursors-are the sister group of pterosaurs, sharing numerous synapomorphies across the entire skeleton. This finding substantially shortens the temporal and morphological gap between the oldest pterosaurs and their closest relatives and simultaneously strengthens the evidence that pterosaurs belong to the avian line of archosaurs. Neuroanatomical features related to the enhanced sensory abilities of pterosaurs9 are already present in lagerpetids, which indicates that these features evolved before flight. Our evidence illuminates the first steps of the assembly of the pterosaur body plan, whose conquest of aerial space represents a remarkable morphofunctional innovation in vertebrate evolution.


Assuntos
Osso e Ossos/anatomia & histologia , Dinossauros/anatomia & histologia , Dinossauros/classificação , Fósseis , Filogenia , Animais , Calibragem , Crânio/anatomia & histologia , Fatores de Tempo , Asas de Animais/anatomia & histologia , Microtomografia por Raio-X
2.
Mol Cell Proteomics ; 22(3): 100503, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36682716

RESUMO

Acute myeloid leukemia (AML) is the most common and aggressive form of acute leukemia, with a 5-year survival rate of just 24%. Over a third of all AML patients harbor activating mutations in kinases, such as the receptor tyrosine kinases FLT3 (receptor-type tyrosine-protein kinase FLT3) and KIT (mast/stem cell growth factor receptor kit). FLT3 and KIT mutations are associated with poor clinical outcomes and lower remission rates in response to standard-of-care chemotherapy. We have recently identified that the core kinase of the non-homologous end joining DNA repair pathway, DNA-PK (DNA-dependent protein kinase), is activated downstream of FLT3; and targeting DNA-PK sensitized FLT3-mutant AML cells to standard-of-care therapies. Herein, we investigated DNA-PK as a possible therapeutic vulnerability in KIT mutant AML, using isogenic FDC-P1 mouse myeloid progenitor cell lines transduced with oncogenic mutant KIT (V560G and D816V) or vector control. Targeted quantitative phosphoproteomic profiling identified phosphorylation of DNA-PK in the T2599/T2605/S2608/S2610 cluster in KIT mutant cells, indicative of DNA-PK activation. Accordingly, proliferation assays revealed that KIT mutant FDC-P1 cells were more sensitive to the DNA-PK inhibitors M3814 or NU7441, compared with empty vector controls. DNA-PK inhibition combined with inhibition of KIT signaling using the kinase inhibitors dasatinib or ibrutinib, or the protein phosphatase 2A activators FTY720 or AAL(S), led to synergistic cell death. Global phosphoproteomic analysis of KIT-D816V cells revealed that dasatinib and M3814 single-agent treatments inhibited extracellular signal-regulated kinase and AKT (RAC-alpha serine/threonine-protein kinase)/MTOR (serine/threonine-protein kinase mTOR) activity, with greater inhibition of both pathways when used in combination. Combined dasatinib and M3814 treatment also synergistically inhibited phosphorylation of the transcriptional regulators MYC and MYB. This study provides insight into the oncogenic pathways regulated by DNA-PK beyond its canonical role in DNA repair and demonstrates that DNA-PK is a promising therapeutic target for KIT mutant cancers.


Assuntos
Proteína Quinase Ativada por DNA , Leucemia Mieloide Aguda , Animais , Camundongos , Apoptose , Linhagem Celular Tumoral , Dasatinibe , DNA , Proteína Quinase Ativada por DNA/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Mutação , Inibidores de Proteínas Quinases/farmacologia , Receptores Proteína Tirosina Quinases , Serina , Transdução de Sinais , Treonina , Serina-Treonina Quinases TOR , Tirosina
3.
Biol Lett ; 20(7): 20240136, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38982977

RESUMO

Recent studies suggest that both stem- and crown-group Archosauria encompassed high ecological diversity during their initial Triassic radiation. We describe a new pseudosuchian archosaur, Benggwigwishingasuchus eremicarminis gen. et sp. nov., from the Anisian (Middle Triassic) Fossil Hill Member of the Favret Formation (Nevada, USA), a pelagic setting in the eastern Panthalassan Ocean characterized by the presence of abundant ammonoids and large-bodied ichthyosaurs. Coupled with archosauriforms from the eastern and western Tethys Ocean, Benggwigwishingasuchus reveals that pseudosuchians were also components of Panthalassan ocean coastal settings, establishing that the group occupied these habitats globally during the Middle Triassic. However, Benggwigwishingasuchus, Qianosuchus, and Ticinosuchus (two other pseudosuchians known from marine sediments) are not recovered in a monophyletic group, demonstrating that a nearshore marine lifestyle occurred widely across Archosauriformes during this time. Benggwigwishingasuchus is recovered as part of an expanded Poposauroidea, including several taxa (e.g. Mandasuchus, Mambawakalae) from the Middle Triassic Manda Beds of Tanzania among its basally branching members. This implies a greater undiscovered diversity of poposauroids during the Early Triassic, and supports that the group, and pseudosuchians more broadly, diversified rapidly following the End-Permian mass extinction.


Assuntos
Fósseis , Animais , Fósseis/anatomia & histologia , Nevada , Filogenia , Répteis/anatomia & histologia , Répteis/classificação , Evolução Biológica , Ecossistema
4.
Clin Proteomics ; 19(1): 48, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36536316

RESUMO

Global high-throughput phosphoproteomic profiling is increasingly being applied to cancer specimens to identify the oncogenic signaling cascades responsible for promoting disease initiation and disease progression; pathways that are often invisible to genomics analysis. Hence, phosphoproteomic profiling has enormous potential to inform and improve individualized anti-cancer treatment strategies. However, to achieve the adequate phosphoproteomic depth and coverage necessary to identify the activated, and hence, targetable kinases responsible for driving oncogenic signaling pathways, affinity phosphopeptide enrichment techniques are required and often coupled with offline high-pressure liquid chromatographic (HPLC) separation prior to nanoflow liquid chromatography-tandem mass spectrometry (nLC-MS/MS). These complex and time-consuming procedures, limit the utility of phosphoproteomics for the analysis of individual cancer patient specimens in real-time, and restrict phosphoproteomics to specialized laboratories often outside of the clinical setting. To address these limitations, here we have optimized a new protocol, phospho-heavy-labeled-spiketide FAIMS Stepped-CV DDA (pHASED), that employs online phosphoproteome deconvolution using high-field asymmetric waveform ion mobility spectrometry (FAIMS) and internal phosphopeptide standards to provide accurate label-free quantitation (LFQ) data in real-time. Compared with traditional single-shot LFQ phosphoproteomics workflows, pHASED provided increased phosphoproteomic depth and coverage (phosphopeptides = 4617 pHASED, 2789 LFQ), whilst eliminating the variability associated with offline prefractionation. pHASED was optimized using tyrosine kinase inhibitor (sorafenib) resistant isogenic FLT3-mutant acute myeloid leukemia (AML) cell line models. Bioinformatic analysis identified differential activation of the serine/threonine protein kinase ataxia-telangiectasia mutated (ATM) pathway, responsible for sensing and repairing DNA damage in sorafenib-resistant AML cell line models, thereby uncovering a potential therapeutic opportunity. Herein, we have optimized a rapid, reproducible, and flexible protocol for the characterization of complex cancer phosphoproteomes in real-time, a step towards the implementation of phosphoproteomics in the clinic to aid in the selection of anti-cancer therapies for patients.

5.
J Strength Cond Res ; 36(12): 3541-3550, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34175880

RESUMO

ABSTRACT: Smith, NDW, Scott, BR, Girard, O, and Peiffer, JJ. Aerobic training with blood flow restriction for endurance athletes: potential benefits and considerations of implementation. J Strength Cond Res 36(12): 3541-3550, 2022-Low-intensity aerobic training with blood flow restriction (BFR) can improve maximal oxygen uptake, delay the onset of blood lactate accumulation, and may provide marginal benefits to economy of motion in untrained individuals. Such a training modality could also improve these physiological attributes in well-trained athletes. Indeed, aerobic BFR training could be beneficial for those recovering from injury, those who have limited time for training a specific physiological capacity, or as an adjunct training stimulus to provide variation in a program. However, similarly to endurance training without BFR, using aerobic BFR training to elicit physiological adaptations in endurance athletes will require additional considerations compared with nonendurance athletes. The objective of this narrative review is to discuss the acute and chronic aspects of aerobic BFR exercise for well-trained endurance athletes and highlight considerations for its effective implementation. This review first highlights key physiological capacities of endurance performance. The acute and chronic responses to aerobic BFR exercise and their impact on performance are then discussed. Finally, considerations for prescribing and monitoring aerobic BFR exercise in trained endurance populations are addressed to challenge current views on how BFR exercise is implemented.


Assuntos
Treino Aeróbico , Músculo Esquelético , Humanos , Fluxo Sanguíneo Regional/fisiologia , Músculo Esquelético/fisiologia , Atletas , Hemodinâmica
6.
Proc Biol Sci ; 287(1939): 20202258, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33234083

RESUMO

The independent evolution of gigantism among dinosaurs has been a topic of long-standing interest, but it remains unclear if gigantic theropods, the largest bipeds in the fossil record, all achieved massive sizes in the same manner, or through different strategies. We perform multi-element histological analyses on a phylogenetically broad dataset sampled from eight theropod families, with a focus on gigantic tyrannosaurids and carcharodontosaurids, to reconstruct the growth strategies of these lineages and test if particular bones consistently preserve the most complete growth record. We find that in skeletally mature gigantic theropods, weight-bearing bones consistently preserve extensive growth records, whereas non-weight-bearing bones are remodelled and less useful for growth reconstruction, contrary to the pattern observed in smaller theropods and some other dinosaur clades. We find a heterochronic pattern of growth fitting an acceleration model in tyrannosaurids, with allosauroid carcharodontosaurids better fitting a model of hypermorphosis. These divergent growth patterns appear phylogenetically constrained, representing extreme versions of the growth patterns present in smaller coelurosaurs and allosauroids, respectively. This provides the first evidence of a lack of strong mechanistic or physiological constraints on size evolution in the largest bipeds in the fossil record and evidence of one of the longest-living individual dinosaurs ever documented.


Assuntos
Evolução Biológica , Tamanho Corporal , Dinossauros , Animais , Osso e Ossos/fisiologia , Fósseis , Filogenia
7.
J Child Adolesc Subst Abuse ; 28(4): 259-265, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-33033427

RESUMO

AIM: Prevention of illicit or nonmedical opioid use, called opioid misuse (OM) is a key public health concern that requires research on the factors that influence OM initiation among high-risk populations. Justice-involved children (JIC) have more risk factors and fewer resources. Antisocial peers have been linked to adolescent substance abuse and delinquency. However, the association between the admiration of antisocial peers and OM among JIC has not yet been studied. This study hypothesizes that admiration of antisocial peers will be associated with a higher likelihood of OM among Florida JIC. METHODS: Cross-sectional data on 79,960 JIC from the Florida Department of Juvenile Justice (FLDJJ) were examined. To test the hypothesis, bivariate and multivariate logistic regression analyses were employed. The multivariate models controlled for gender, race, age in 2007, family income, history of mental health, history of depression, and optimism. RESULTS: Nearly 2.7% of the sample met the criteria for past 30-day OM, and over 75% of those current users admired or somewhat admired their antisocial peers. Compare to JIC who did not admire their antisocial peers, those who had some admiration of antisocial peers were 2.39 times more likely to misuse opioids in the past 30-days and those who admired their antisocial peers were 4.40 times more likely to meet the criteria for past 30-day OM. CONCLUSIONS: Cultivating positive peer interactions and providing positive peer role models may help to reduce illicit opioid use among JIC.

9.
Proc Natl Acad Sci U S A ; 112(26): 7909-13, 2015 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-26080428

RESUMO

A major unresolved aspect of the rise of dinosaurs is why early dinosaurs and their relatives were rare and species-poor at low paleolatitudes throughout the Late Triassic Period, a pattern persisting 30 million years after their origin and 10-15 million years after they became abundant and speciose at higher latitudes. New palynological, wildfire, organic carbon isotope, and atmospheric pCO2 data from early dinosaur-bearing strata of low paleolatitudes in western North America show that large, high-frequency, tightly correlated variations in δ(13)Corg and palynomorph ecotypes occurred within a context of elevated and increasing pCO2 and pervasive wildfires. Whereas pseudosuchian archosaur-dominated communities were able to persist in these same regions under rapidly fluctuating extreme climatic conditions until the end-Triassic, large-bodied, fast-growing tachymetabolic dinosaurian herbivores requiring greater resources were unable to adapt to unstable high CO2 environmental conditions of the Late Triassic.


Assuntos
Dinossauros , Ecossistema , Clima Tropical , Animais , Isótopos de Carbono/análise , Incêndios , Temperatura Alta
10.
Proteomics ; 17(17-18)2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28782881

RESUMO

Early pregnancy in the mare is a poorly understood, high risk period during which the embryo communicates its presence to the maternal endometrium. Remarkably, the maternal recognition of pregnancy signal is unknown in the horse. This study aimed to profile the proteins secreted by equine blastocysts into their immediate environment, along with proteins contained in the blastocoel and within the acellular embryo capsule. Embryos were recovered on day 8 after ovulation and cultured for 48 hours. Secretomes of day 9 and day 10 embryos were analyzed by LC-MS/MS and supported by analysis of blastocoel fluid and embryo capsule. Analyses revealed 72 (24 h) and 97 (48 h) unique protein IDs in the embryo secretome, 732 protein IDs in blastocoel fluid, and 11 proteins IDs in the embryo capsule. Novel findings of interest include secretion of a pregnancy specific proteinase (PAG) by the equine embryo at day 10, along with detection of a prostaglandin receptor inhibiting protein (PTGFRN) and a progesterone potentiating factor (FKBP4) in blastocoel fluid. This is the first comprehensive proteomic analysis of the equine embryo secretome, and provides new insights into the unique physiology of early pregnancy in this species.


Assuntos
Blastocisto/metabolismo , Embrião de Mamíferos/metabolismo , Cavalos/embriologia , Cavalos/metabolismo , Fragmentos de Peptídeos/metabolismo , Manutenção da Gravidez , Animais , Embrião de Mamíferos/citologia , Feminino , Gravidez , Proteômica/métodos
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