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1.
bioRxiv ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38370755

RESUMO

Mechanistic Target of Rapamycin Complex 1 (mTORC1) is a master metabolic regulator that stimulates anabolic cell growth while suppressing catabolic processes such as autophagy. mTORC1 is active in most, if not all, proliferating eukaryotic cells. However, it remains unclear whether and how mTORC1 activity changes from one cell cycle phase to another. Here we tracked mTORC1 activity through the complete cell cycle and uncover oscillations in its activity. We find that mTORC1 activity peaks in S and G2, and is lowest in mitosis and G1. We further demonstrate that multiple mechanisms are involved in controlling this oscillation. The interphase oscillation is mediated through the TSC complex, an upstream negative regulator of mTORC1, but is independent of major known regulatory inputs to the TSC complex, including Akt, Mek/Erk, and CDK4/6 signaling. By contrast, suppression of mTORC1 activity in mitosis does not require the TSC complex, and instead involves CDK1-dependent control of the subcellular localization of mTORC1 itself. Functionally, we find that in addition to its well-established role in promoting progression through G1, mTORC1 also promotes progression through S and G2, and is important for satisfying the Wee1- and Chk1- dependent G2/M checkpoint to allow entry into mitosis. We also find that low mTORC1 activity in G1 sensitizes cells to autophagy induction in response to partial mTORC1 inhibition or reduced nutrient levels. Together these findings demonstrate that mTORC1 is differentially regulated throughout the cell cycle, with important phase-specific functional consequences in proliferating cells.

2.
Clin Lung Cancer ; 24(3): 260-268, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36641325

RESUMO

BACKGROUND: As the non-small cell lung cancer (NSCLC) adjuvant treatment landscape evolves, an evaluation of treatment patterns and outcomes of patients with early-stage, resected NSCLC eligible for adjuvant treatment in routine clinical practice is needed to better understand the unmet needs in this patient population. MATERIALS AND METHODS: Data from the Surveillance, Epidemiology, and End Results (SEER)-Medicare database (2007-2019) were used to identify patients with newly diagnosed stage IB (tumor size ≥4cm)-IIIA (AJCC 7th edition) NSCLC who received primary surgery (index date). We assessed adjuvant treatment patterns, real-world disease-free survival (rwDFS; time from index date to first recurrence or death) and overall survival (OS; time from index date to death), and loco-regional recurrence pattern and treatment distribution. RESULTS: Among 1761 patients with primary surgery, mean age was 73.8 years; 47.9% were male; and 83.9% were white. Approximately 41% of patients received adjuvant chemotherapy; median time from surgery to adjuvant chemotherapy initiation was 48 days, and the most frequently observed adjuvant chemotherapy regimen was carboplatin+paclitaxel (24.5%). In the overall population, median rwDFS was 24.8 months and OS was 76.7 months; 5-year rwDFS and OS rates were 29.3% and 57.5%, respectively. Among 392 patients with loco-regional recurrence, the most frequently observed treatment was curative radiation monotherapy (28.2%). CONCLUSION: Despite clinical guideline recommendations, rate of adjuvant chemotherapy among patients with resected early-stage NSCLC was low in clinical practice. Overall, among patients with early-stage NSCLC treated with conventional primary surgery, poor survival outcomes were observed, highlighting the need for and importance of more effective adjuvant treatments.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Masculino , Idoso , Estados Unidos/epidemiologia , Feminino , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Medicare , Carboplatina , Carcinoma de Pequenas Células do Pulmão/patologia , Quimioterapia Adjuvante , Estadiamento de Neoplasias
3.
Am J Bot ; 108(7): 1122-1142, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34254290

RESUMO

PREMISE: Phylogenetic relationships within major angiosperm clades are increasingly well resolved, but largely informed by plastid data. Areas of poor resolution persist within the Dipsacales, including placement of Heptacodium and Zabelia, and relationships within the Caprifolieae and Linnaeeae, hindering our interpretation of morphological evolution. Here, we sampled a significant number of nuclear loci using a Hyb-Seq approach and used these data to infer the Dipsacales phylogeny and estimate divergence times. METHODS: Sampling all major clades within the Dipsacales, we applied the Angiosperms353 probe set to 96 species. Data were filtered based on locus completeness and taxon recovery per locus, and trees were inferred using RAxML and ASTRAL. Plastid loci were assembled from off-target reads, and 10 fossils were used to calibrate dated trees. RESULTS: Varying numbers of targeted loci and off-target plastomes were recovered from most taxa. Nuclear and plastid data confidently place Heptacodium with Caprifolieae, implying homoplasy in calyx morphology, ovary development, and fruit type. Placement of Zabelia, and relationships within the Caprifolieae and Linnaeeae, remain uncertain. Dipsacales diversification began earlier than suggested by previous angiosperm-wide dating analyses, but many major splitting events date to the Eocene. CONCLUSIONS: The Angiosperms353 probe set facilitated the assembly of a large, single-copy nuclear dataset for the Dipsacales. Nevertheless, many relationships remain unresolved, and resolution was poor for woody clades with low rates of molecular evolution. We favor expanding the Angiosperms353 probe set to include more variable loci and loci of special interest, such as developmental genes, within particular clades.


Assuntos
Caprifoliaceae , Dipsacales , Evolução Molecular , Fósseis , Filogenia
4.
J Orthop Trauma ; 34(4): 174-179, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31652187

RESUMO

OBJECTIVES: To evaluate the reliability, sensitivity, and specificity of the Squat and Smile (S&S) test, a clinical photographic follow-up, in determination of fracture healing and to assess the extent of continued fracture healing beyond 1-year postoperation. DESIGN: Retrospective review of the Surgical Implant Generation Network (SIGN) database. SETTING: The S&S test is utilized in low-resource settings where the SIGN intramedullary nail is used due to unavailability of intraoperative fluoroscopy. PATIENTS/PARTICIPANTS: One hundred fifty patients undergoing fracture fixation utilizing SIGN intramedullary nails with data available at least 1 year (9-16 months) after surgery. INTERVENTION: None. MAIN OUTCOME MEASURES: We extracted clinical data and calculated scores for the S&S photographs and radiographs at the 1-year (9-16 month postoperative) follow-up and last follow-up available beyond that. We analyzed the sensitivity of S&S scoring, using Radiographic Union Scale for Tibia fracture scores as the gold standard for fracture union. RESULTS: Of the 126 patients analyzed, 21% were found to have incomplete healing at 1 year, whereas 17% of the 64 patients with further follow-up past 1 year had incomplete healing. We found that both S&S and radiographic fracture healing scores had good interrater reliability (k = 0.73-0.78 for S&S and 0.94 for radiographs). The S&S test had poor sensitivity (0.11) and specificity (0.85) in determining fracture healing at the 1-year follow-up. CONCLUSIONS: The S&S scoring method was reliable but neither sensitive nor specific for determining fracture healing at 1 year. Fractures deemed incompletely healed by radiographic evaluation at 1 year after SIGN implant may still have the potential to heal over time. LEVEL OF EVIDENCE: Diagnostic Level IV. See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Fixação Intramedular de Fraturas , Consolidação da Fratura , Pinos Ortopédicos , Humanos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Resultado do Tratamento
5.
PLoS One ; 14(3): e0213382, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30870447

RESUMO

PURPOSE: The Ponseti Method has dramatically altered the management of clubfoot, with particular implications for limited-resource settings. We sought to describe outcomes of care and risk factors for sub-optimal results using the Ponseti Method in Haiti. METHODS: We conducted a records review of patients presenting from 2011-2015 to a CURE Clubfoot clinic in Port-au-Prince, Haiti. We report patient characteristics (demographics and clinical), treatment patterns (cast number/duration and tenotomy rates), and outcomes (relapse and complications). We compared treatment with benchmarks in high-income nations and used generalized linear models to identify risk factors for delayed presentation, increased number of casts, and relapse. RESULTS: Amongst 168 children, age at presentation ranged from 0 days (birth) to 4.4 years, 62% were male, 35% were born at home, 63% had bilateral disease, and 46% had idiopathic clubfeet. Prior treatment (RR 6.33, 95% CI 3.18-12.62) was associated with a higher risk of delayed presentation. Risk factors for requiring ≥ 10 casts included having a non-idiopathic diagnosis (RR 2.28, 95% CI 1.08-4.83) and higher Pirani score (RR 2.78 per 0.5 increase, 95% CI 1.17-6.64). Female sex (RR 1.54, 95% CI 1.01-2.34) and higher Pirani score (RR 1.09 per 0.5 increase, 95% CI 1.00-1.17) were risk factors for relapse. Compared to North American benchmarks, children presented later (median 4.1 wks [IQR 1.6-18.1] vs. 1 wk), with longer casting (12.5 wks [SD 9.8] vs. 7.1 wks), and higher relapse (43% vs. 22%). CONCLUSIONS: Higher Pirani score, prior treatment, non-idiopathic diagnosis, and female sex were associated with a higher risk of sub-optimal outcomes in this low-resource setting. Compared to high-income nations, serial casting began later, with longer duration and higher relapse. Identifying patients at risk for poor outcomes in a low-resource setting can guide counseling, program development, and resource allocation.


Assuntos
Pé Torto Equinovaro/terapia , Braquetes , Moldes Cirúrgicos , Pré-Escolar , Feminino , Haiti , Humanos , Lactente , Recém-Nascido , Modelos Lineares , Masculino , Recidiva , Estudos Retrospectivos , Fatores de Risco , Tenotomia , Resultado do Tratamento
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