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1.
Circulation ; 148(25): 2029-2037, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-37886885

RESUMO

BACKGROUND: In severely affected patients with catecholaminergic polymorphic ventricular tachycardia, beta-blockers are often insufficiently protective. The purpose of this study was to evaluate whether flecainide is associated with a lower incidence of arrhythmic events (AEs) when added to beta-blockers in a large cohort of patients with catecholaminergic polymorphic ventricular tachycardia. METHODS: From 2 international registries, this multicenter case cross-over study included patients with a clinical or genetic diagnosis of catecholaminergic polymorphic ventricular tachycardia in whom flecainide was added to beta-blocker therapy. The study period was defined as the period in which background therapy (ie, beta-blocker type [beta1-selective or nonselective]), left cardiac sympathetic denervation, and implantable cardioverter defibrillator treatment status, remained unchanged within individual patients and was divided into pre-flecainide and on-flecainide periods. The primary end point was AEs, defined as sudden cardiac death, sudden cardiac arrest, appropriate implantable cardioverter defibrillator shock, and arrhythmic syncope. The association of flecainide with AE rates was assessed using a generalized linear mixed model assuming negative binomial distribution and random effects for patients. RESULTS: A total of 247 patients (123 [50%] females; median age at start of flecainide, 18 years [interquartile range, 14-29]; median flecainide dose, 2.2 mg/kg per day [interquartile range, 1.7-3.1]) were included. At baseline, all patients used a beta-blocker, 70 (28%) had an implantable cardioverter defibrillator, and 21 (9%) had a left cardiac sympathetic denervation. During a median pre-flecainide follow-up of 2.1 years (interquartile range, 0.4-7.2), 41 patients (17%) experienced 58 AEs (annual event rate, 5.6%). During a median on-flecainide follow-up of 2.9 years (interquartile range, 1.0-6.0), 23 patients (9%) experienced 38 AEs (annual event rate, 4.0%). There were significantly fewer AEs after initiation of flecainide (incidence rate ratio, 0.55 [95% CI, 0.38-0.83]; P=0.007). Among patients who were symptomatic before diagnosis or during the pre-flecainide period (n=167), flecainide was associated with significantly fewer AEs (incidence rate ratio, 0.49 [95% CI, 0.31-0.77]; P=0.002). Among patients with ≥1 AE on beta-blocker therapy (n=41), adding flecainide was also associated with significantly fewer AEs (incidence rate ratio, 0.25 [95% CI, 0.14-0.45]; P<0.001). CONCLUSIONS: For patients with catecholaminergic polymorphic ventricular tachycardia, adding flecainide to beta-blocker therapy was associated with a lower incidence of AEs in the overall cohort, in symptomatic patients, and particularly in patients with breakthrough AEs while on beta-blocker therapy.


Assuntos
Desfibriladores Implantáveis , Taquicardia Ventricular , Feminino , Humanos , Adolescente , Masculino , Flecainida/efeitos adversos , Incidência , Estudos Cross-Over , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/tratamento farmacológico , Taquicardia Ventricular/epidemiologia , Antagonistas Adrenérgicos beta/efeitos adversos , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/prevenção & controle
2.
Antimicrob Agents Chemother ; 68(3): e0106423, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38349161

RESUMO

Screening a library of 1,200 preselected kinase inhibitors for anti-human rhinovirus 2 (HRV-2) activity in HeLa cells identified a class of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKI) as effective virus blockers. These were based on the 4-anilinoquinazoline-7-oxypiperidine scaffold, with the most potent representative AZ5385 inhibiting the virus with EC50 of 0.35 µM. Several structurally related analogs confirmed activity in the low µM range, while interestingly, other TKIs targeting EGFR lacked anti-HRV-2 activity. To further probe this lack of association between antiviral activity and EGFR inhibition, we stained infected cells with antibodies specific for activated EGFR (Y1068) and did not observe a dependency on EGFR-TK activity. Instead, consecutive passages of HRV-2 in HeLa cells in the presence of a compound and subsequent nucleotide sequence analysis of resistant viral variants identified the S181T and T210A alterations in the major capsid VP1 protein, with both residues located in the vicinity of a known hydrophobic pocket on the viral capsid. Further characterization of the antiviral effects of AZ5385 showed a modest virus-inactivating (virucidal) activity, while anti-HRV-2 activity was still evident when the inhibitor was added as late as 10 h post infection. The RNA copy/infectivity ratio of HRV-2 propagated in AZ5385 presence was substantially higher than that of control HRV indicating that the compound preferentially targeted HRV progeny virions during their maturation in infected cells. Besides HRV, the compound showed anti-respiratory syncytial virus activity, which warrants its further studies as a candidate compound against viral respiratory infections.


Assuntos
Rhinovirus , Humanos , Rhinovirus/química , Rhinovirus/genética , Células HeLa , Proteínas do Capsídeo , Antivirais/química , Receptores ErbB
3.
Oncologist ; 29(2): 123-131, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-37935631

RESUMO

BACKGROUND: The MONARCH 2 trial (NCT02107703) showed the efficacy of abemaciclib, a cyclin-dependent kinase 4 & 6 inhibitor (CDK4/6i), in combination with fulvestrant for hormone receptor-positive, HER2-negative metastatic breast cancer (MBC). The aim of this analysis was to explore the prediction of circulating tumor cells (CTCs) stratification using machine learning for hypothesis generation of biomarker-driven clinical trials. PATIENTS AND METHODS: Predicted CTCs were computed in the MONARCH 2 trial through a K nearest neighbor (KNN) classifier trained on a dataset comprising 2436 patients with MBC. Patients were categorized into predicted Stage IVaggressive (pStage IVaggressive, ≥5 predicted CTCs) or predicted Stage IVindolent (pStage IVindolent, <5 predicted CTCs). Prognosis was tested in terms of progression-free-survival (PFS) and overall survival (OS) through Cox regression. RESULTS: Patients classified as predicted pStage IVaggressive and predicted pStage Stage IVindolent were, respectively, 183 (28%) and 461 (72%). After multivariable Cox regression, predicted CTCs were confirmed as independently associated with prognosis in terms of OS, together with ECOG performance status, liver involvement, bone-only disease, and treatment arm. Patients in the pStage Stage IVindolent subgroup treated with abemaciclib experienced the best prognosis both in terms of PFS and OS. The treatment effect of abemaciclib on OS was then explored through subgroup analysis, showing a consistent benefit across all subgroups. CONCLUSION: This study is the first analysis of CTCs modeling for stage IV disease stratification. These results show the need to expand biomarker profiling in combination with CTCs stratification for improved biomarker-driven drug development.


Assuntos
Aminopiridinas , Benzimidazóis , Neoplasias da Mama , Células Neoplásicas Circulantes , Humanos , Feminino , Células Neoplásicas Circulantes/patologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Receptor ErbB-2/genética , Receptor ErbB-2/uso terapêutico , Estudos Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
4.
Anal Chem ; 96(1): 170-178, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38155534

RESUMO

Characterization of the elemental distribution of samples with rough surfaces has been strongly desired for the analysis of various natural and artificial materials. Particularly for pristine and rare analytes with micrometer sizes embedded on specimen surfaces, non-invasive and matrix effect-free analysis is required without surface polishing treatment. To satisfy these requirements, we proposed a new method employing the sequential combination of two imaging modalities, i.e., microenergy-dispersive X-ray fluorescence (micro-XRF) and Raman micro-spectroscopy. The applicability of the developed method is tested by the quantitative analysis of cation composition in micrometer-sized carbonate grains on the surfaces of intact particles sampled directly from the asteroid Ryugu. The first step of micro-XRF imaging enabled a quick search for the sparsely scattered and micrometer-sized carbonates by the codistributions of Ca2+ and Mn2+ on the Mg2+- and Fe2+-rich phyllosilicate matrix. The following step of Raman micro-spectroscopy probed the carbonate grains and analyzed their cation composition (Ca2+, Mg2+, and Fe2+ + Mn2+) in a matrix effect-free manner via the systematic Raman shifts of the lattice modes. The carbonates were basically assigned to ferroan dolomite bearing a considerable amount of Fe2+ + Mn2+ at around 10 atom %. These results are in good accordance with the assignments reported by scanning electron microscopy-energy-dispersive X-ray spectroscopy, where the thin-sectioned and surface-polished Ryugu particles were applicable. The proposed method requires neither sectioning nor surface polishing; hence, it can be applied to the remote sensing apparatus on spacecrafts and planetary rovers. Furthermore, the non-invasive and matrix effect-free characterization will provide a reliable analytical tool for quantitative analysis of the elemental distribution on the samples with surface roughness and chemical heterogeneity at a micrometer scale, such as art paintings, traditional crafts with decorated shapes, as well as sands and rocks with complex morphologies in nature.

5.
J Viral Hepat ; 31(4): 176-180, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38369695

RESUMO

Hepatitis C virus (HCV) causes significant mortality worldwide. HCV is highly curable but access to care is limited for many patients. The Grady Liver Clinic (GLC), a primary care-based HCV clinic, utilizes a multidisciplinary team to provide comprehensive care for a medically underserved patient population in Atlanta, Georgia. The GLC added a telehealth option for HCV treatment at the start of the COVID-19 pandemic. We describe the outcomes of utilizing telehealth in this population. We performed a retrospective chart review of patients who initiated HCV treatment from March 2019 to February 2020 (pre-pandemic) and March 2020 to February 2021 (pandemic). Charts were abstracted for patient demographics and characteristics, treatment regimen, and treatment outcomes. Our primary outcome was HCV cure rate of the pre-pandemic compared to the pandemic cohorts and within the different pandemic cohort visit types. We performed an intention-to-treat (ITT) analysis for all patients who took at least one dose of a direct-acting antiviral (DAA) regardless of therapy completion, and a per-protocol (PP) analysis of those who completed treatment and were tested for HCV cure. SVR12 rates were >95% on ITT analysis, with no significant difference between pre-pandemic and pandemic cohorts. There was also no significant difference within the pandemic group when treatment was provided traditionally, via telehealth, or via a hybrid of these. Our findings support the use of telehealth as a tool to expand access to HCV treatment in a medically underserved patient population.


Assuntos
Hepatite C Crônica , Hepatite C , Telemedicina , Humanos , Antivirais/uso terapêutico , Estudos Retrospectivos , Hepatite C Crônica/tratamento farmacológico , Provedores de Redes de Segurança , Pandemias , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Hepacivirus
6.
Int J Cosmet Sci ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38685700

RESUMO

OBJECTIVE: Topical tretinoin is the mainstay of treatment for photoageing, despite the risk of skin irritation. Cosmetic combination anti-ageing formulations may offer similar efficacy to tretinoin, while improving on tolerability. We aim to demonstrate facial appearance benefits of a novel triple-active cosmetic formulation containing 4-hexylresorcinol, retinyl propionate, and niacinamide and to identify transcriptomic biomarkers underpinning these benefits. METHODS: A cosmetic prototype formulation containing 4-hexylresorcinol, retinyl propionate, and niacinamide was evaluated ex vivo and in a clinical study. For ex vivo experiments, the cosmetic formulation was applied for 3 days to healthy surgical discard skin from female donors aged 31-51 years, with tissues harvested for gene expression and histologic analyses. In the clinical study, females aged 47-66 years with moderate-to-severe overall visual photodamage on the face applied either topical 0.02% tretinoin or the cosmetic formulation to the face for 16 weeks and to forearms for 1 week, with forearm biopsies taken for gene expression analyses. Visual grading for facial photodamage and VISIA-CR images was taken throughout the clinical study. Safety was visually assessed during site visits, and adverse event monitoring was conducted throughout. RESULTS: Gene expression analyses in both studies revealed modulation of pathways associated with skin rejuvenation, with several genes of interest identified due to being implicated in ageing and differentially expressed following the application of the cosmetic formulation. Reversal of a consensus skin ageing gene signature was observed with the cosmetic formulation and tretinoin in the ex vivo and clinical studies. Both the cosmetic formulation and tretinoin clinically improved the overall appearance of photoageing, crow's feet, lines, wrinkles, and pores. Adverse event reporting showed that the cosmetic formulation caused less skin irritation than tretinoin. CONCLUSION: In a double-blind clinical study, the novel triple-active cosmetic combination formulation improved the visual appearance of photoageing similarly to prescription tretinoin. The cosmetic formulation and tretinoin reversed a consensus gene signature associated with ageing. Together with adverse event reporting, these results suggest that the cosmetic formulation may be a well-tolerated and efficacious alternative to tretinoin for improving the visual features of photoageing.


OBJECTIF: Le trétinoine topique est le pilier du traitement du photovieillissement, malgré le risque d'irritation cutanée. Les formulations cosmétiques combinés anti­âge peuvent offrir une efficacité similaire à la trétinoine, tout en améliorant la tolérance. Notre objectif est de démontrer les avantages esthétiques pour l'apparence du visage d'une nouvelle formulation cosmétique triple active contenant du 4­hexylrésorcinol, du rétinyl propionate et de la niacinamide, et d'identifier les biomarqueurs transcriptomiques sous­jacents à ces avantages. MÉTHODES: Une formulation cosmétique prototype contenant du 4­hexylrésorcinol, du rétinyl propionate et de la niacinamide a été évaluée ex vivo et lors d'une étude clinique. Pour les expériences ex vivo, la formulation cosmétique a été appliquée pendant 3 jours sur des peaux saines issues de donatrices âgées de 31 à 51 ans, avec prélèvement de tissus pour l'analyse de l'expression génique et l'histologie. Dans l'étude clinique, des femmes âgées de 47 à 66 ans présentant un photovieillissement visuel global modéré a sévère sur le visage ont appliqué soit du trétinoine topique à 0.02%, soit la formulation cosmétique sur le visage pendant 16 semaines et sur les avant­bras pendant 1 semaine, avec des biopsies d'avant­bras prélevées pour l'analyse de l'expression génique. L'évaluation visuelle du photovieillissement facial et les images VISIA­CR ont été réalisées tout au long de l'étude clinique. La sécurité a été évaluée visuellement lors des visites sur site, et une surveillance des événements indésirables a été effectuée. RÉSULTATS: Les analyses de l'expression génique dans les deux études ont révélé une modulation des voies associées au rajeunissement cutané, avec plusieurs gènes d'intérêts identifiés en raison de leur implication dans le vieillissement et de leur expression différentielle suite à l'application de la formulation cosmétique. Une inversion de la signature génique du vieillissement cutané consensuelle a été observée avec la formulation cosmétique et la trétinoine dans les études ex vivo et cliniques. La formulation cosmétique et la trétinoine ont toutes deux amélioré cliniquement l'apparence globale du photovieillissement, des pattes d'oie, des ridules, des rides et des pores. Les rapports sur les événements indésirables ont montré que la formulation cosmétique provoquait moins d'irritation cutanée que la trétinoine. CONCLUSION: Dans une étude clinique en double aveugle, la nouvelle formulation cosmétique triple active a amélioré l'apparence visuelle du photovieillissement de manière similaire à la trétinoine sur ordonnance. La formulation cosmétique et la trétinoine ont inversé une signature génique consensuelle associée au vieillissement. En tenant compte des rapports sur les événements indésirables, ces résultats suggèrent que la formulation cosmétique pourrait constituer une alternative bien tolérée et efficace à la trétinoine pour améliorer les caractéristiques visuelles du photovieillissement.

7.
Circulation ; 145(5): 333-344, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34874747

RESUMO

BACKGROUND: Symptomatic children with catecholaminergic polymorphic ventricular tachycardia (CPVT) are at risk for recurrent arrhythmic events. ß-Blockers decrease this risk, but studies comparing individual ß-blockers in sizeable cohorts are lacking. We aimed to assess the association between risk for arrhythmic events and type of ß-blocker in a large cohort of symptomatic children with CPVT. METHODS: From 2 international registries of patients with CPVT, RYR2 variant-carrying symptomatic children (defined as syncope or sudden cardiac arrest before ß-blocker initiation and age at start of ß-blocker therapy <18 years), treated with a ß-blocker were included. Cox regression analyses with time-dependent covariates for ß-blockers and potential confounders were used to assess the hazard ratio (HR). The primary outcome was the first occurrence of sudden cardiac death, sudden cardiac arrest, appropriate implantable cardioverter-defibrillator shock, or syncope. The secondary outcome was the first occurrence of any of the primary outcomes except syncope. RESULTS: We included 329 patients (median age at diagnosis, 12 [interquartile range, 7-15] years, 35% females). Ninety-nine (30.1%) patients experienced the primary outcome and 74 (22.5%) experienced the secondary outcome during a median follow-up of 6.7 (interquartile range, 2.8-12.5) years. Two-hundred sixteen patients (66.0%) used a nonselective ß-blocker (predominantly nadolol [n=140] or propranolol [n=70]) and 111 (33.7%) used a ß1-selective ß-blocker (predominantly atenolol [n=51], metoprolol [n=33], or bisoprolol [n=19]) as initial ß-blocker. Baseline characteristics did not differ. The HRs for both the primary and secondary outcomes were higher for ß1-selective compared with nonselective ß-blockers (HR, 2.04 [95% CI, 1.31-3.17]; and HR, 1.99 [95% CI, 1.20-3.30], respectively). When assessed separately, the HR for the primary outcome was higher for atenolol (HR, 2.68 [95% CI, 1.44-4.99]), bisoprolol (HR, 3.24 [95% CI, 1.47-7.18]), and metoprolol (HR, 2.18 [95% CI, 1.08-4.40]) compared with nadolol, but did not differ from propranolol. The HR of the secondary outcome was only higher in atenolol compared with nadolol (HR, 2.68 [95% CI, 1.30-5.55]). CONCLUSIONS: ß1-selective ß-blockers were associated with a significantly higher risk for arrhythmic events in symptomatic children with CPVT compared with nonselective ß-blockers, specifically nadolol. Nadolol, or propranolol if nadolol is unavailable, should be the preferred ß-blocker for treating symptomatic children with CPVT.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Taquicardia Ventricular/tratamento farmacológico , Adolescente , Antagonistas Adrenérgicos beta/farmacologia , Criança , Estudos de Coortes , Feminino , Humanos , Masculino
8.
Breast Cancer Res ; 25(1): 112, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37784176

RESUMO

BACKGROUND: although being central for the biology and druggability of hormone-receptor positive, HER2 negative metastatic breast cancer (MBC), ESR1 and PIK3CA mutations are simplistically dichotomized as mutated or wild type in current clinical practice. METHODS: The study analyzed a multi-institutional cohort comprising 703 patients with luminal-like MBC characterized for circulating tumor DNA through next generation sequencing (NGS). Pathway classification was defined based on previous work (i.e., RTK, RAS, RAF, MEK, NRF2, ER, WNT, MYC, P53, cell cycle, notch, PI3K). Single nucleotide variations (SNVs) were annotated for their oncogenicity through OncoKB. Only pathogenic variants were included in the models. Associations among clinical characteristics, pathway classification, and ESR1/PIK3CA codon variants were explored. RESULTS: The results showed a differential pattern of associations for ESR1 and PIK3CA codon variants in terms of co-occurring pathway alterations patterns of metastatic dissemination, and prognosis. ESR1 537 was associated with SNVs in the ER and RAF pathways, CNVs in the MYC pathway and bone metastases, while ESR1 538 with SNVs in the cell cycle pathway and liver metastases. PIK3CA 1047 and 542 were associated with CNVs in the PI3K pathway and with bone metastases. CONCLUSIONS: The study demonstrated how ESR1 and PIK3CA codon variants, together with alterations in specific oncogenic pathways, can differentially impact the biology and clinical phenotype of luminal-like MBC. As novel endocrine therapy agents such as selective estrogen receptor degraders (SERDS) and PI3K inhibitors are being developed, these results highlight the pivotal role of ctDNA NGS to describe tumor evolution and optimize clinical decision making.


Assuntos
Neoplasias da Mama , DNA Tumoral Circulante , Humanos , Feminino , DNA Tumoral Circulante/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Fosfatidilinositol 3-Quinases/genética , Biomarcadores Tumorais/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Mutação
9.
Support Care Cancer ; 31(4): 213, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36917417

RESUMO

PURPOSE: To determine how participation in daily life is impacted during the first six months following a new cancer diagnosis and to identify risk factors for participation restrictions. Patient-reported outcomes (PROs) were used to suggest referrals to rehabilitation services. METHODS: Participants (n = 123) were adults (> 18 years) with the newly diagnosed primary brain, breast, colorectal, or lung cancer. PROs were collected at baseline (within 30 days of diagnosis/treatment initiation), two and five months post baseline. Daily life participation was assessed through the community participation indicators (CPI) (score range: 0-1) and patient-reported outcome measurement information system (PROMIS) ability to participate, (score range: 20-80; mean: 50, SD: 10). PROMIS-43 profile was also completed. Linear mixed-effect models with random intercept evaluated change in participation over time. RESULTS: The baseline total sample mean CPI score was 0.56; patients reported mildly impaired participation based on PROMIS scores (baseline: 46.19, 2-month follow-up: 44.81, 5 months: 44.84). However, no statistically significant changes in participation were observed over the study period. Risk factors for lower participation included receiving chemotherapy, lower physical function, higher anxiety and fatigue, and reduction in employment, p < 0.05. PROs indicated that roughly half of the participants may benefit from physical or occupational therapy or mental health support, but only 20-36% were referred by their medical team. CONCLUSION: People newly diagnosed with cancer experience impaired participation, but they are infrequently referred to supportive services such as rehabilitation. The use of PROs to assess participation, physical function, and mental health can promote access to supportive care services by identifying patients who may benefit from rehabilitation beyond those identified through routine clinical care.


Assuntos
Neoplasias , Qualidade de Vida , Adulto , Humanos , Estudos Longitudinais , Saúde Mental , Neoplasias/terapia , Ansiedade/etiologia
10.
Cereb Cortex ; 32(6): 1223-1243, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-34416758

RESUMO

Understanding the neural underpinnings of major depressive disorder (MDD) and its treatment could improve treatment outcomes. So far, findings are variable and large sample replications scarce. We aimed to replicate and extend altered functional connectivity associated with MDD and pharmacotherapy outcomes in a large, multisite sample. Resting-state fMRI data were collected from 129 patients and 99 controls through the Canadian Biomarker Integration Network in Depression. Symptoms were assessed with the Montgomery-Åsberg Depression Rating Scale (MADRS). Connectivity was measured as correlations between four seeds (anterior and posterior cingulate cortex, insula and dorsolateral prefrontal cortex) and all other brain voxels. Partial least squares was used to compare connectivity prior to treatment between patients and controls, and between patients reaching remission (MADRS ≤ 10) early (within 8 weeks), late (within 16 weeks), or not at all. We replicated previous findings of altered connectivity in patients. In addition, baseline connectivity of the anterior/posterior cingulate and insula seeds differentiated patients with different treatment outcomes. The stability of these differences was established in the largest single-site subsample. Our replication and extension of altered connectivity highlighted previously reported and new differences between patients and controls, and revealed features that might predict remission prior to pharmacotherapy. Trial registration:ClinicalTrials.gov: NCT01655706.


Assuntos
Transtorno Depressivo Maior , Encéfalo/diagnóstico por imagem , Canadá , Depressão , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/tratamento farmacológico , Humanos , Imageamento por Ressonância Magnética
11.
Proc Natl Acad Sci U S A ; 117(4): 1884-1889, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31932423

RESUMO

We determined interstellar cosmic ray exposure ages of 40 large presolar silicon carbide grains extracted from the Murchison CM2 meteorite. Our ages, based on cosmogenic Ne-21, range from 3.9 ± 1.6 Ma to ∼3 ± 2 Ga before the start of the Solar System ∼4.6 Ga ago. A majority of the grains have interstellar lifetimes of <300 Ma, which is shorter than theoretical estimates for large grains. These grains condensed in outflows of asymptotic giant branch stars <4.9 Ga ago that possibly formed during an episode of enhanced star formation ∼7 Ga ago. A minority of the grains have ages >1 Ga. Longer lifetimes are expected for large grains. We determined that at least 12 of the analyzed grains were parts of aggregates in the interstellar medium: The large difference in nuclear recoil loss of cosmic ray spallation products 3He and 21Ne enabled us to estimate that the irradiated objects in the interstellar medium were up to 30 times larger than the analyzed grains. Furthermore, we estimate that the majority of the grains acquired the bulk of their cosmogenic nuclides in the interstellar medium and not by exposure to an enhanced particle flux of the early active sun.

12.
Angiogenesis ; 25(3): 411-434, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35320450

RESUMO

The small monomeric GTPase RHOA acts as a master regulator of signal transduction cascades by activating effectors of cellular signaling, including the Rho-associated protein kinases ROCK1/2. Previous in vitro cell culture studies suggest that RHOA can regulate many critical aspects of vascular endothelial cell (EC) biology, including focal adhesion, stress fiber formation, and angiogenesis. However, the specific in vivo roles of RHOA during vascular development and homeostasis are still not well understood. In this study, we examine the in vivo functions of RHOA in regulating vascular development and integrity in zebrafish. We use zebrafish RHOA-ortholog (rhoaa) mutants, transgenic embryos expressing wild type, dominant negative, or constitutively active forms of rhoaa in ECs, pharmacological inhibitors of RHOA and ROCK1/2, and Rock1 and Rock2a/b dgRNP-injected zebrafish embryos to study the in vivo consequences of RHOA gain- and loss-of-function in the vascular endothelium. Our findings document roles for RHOA in vascular integrity, developmental angiogenesis, and vascular morphogenesis in vivo, showing that either too much or too little RHOA activity leads to vascular dysfunction.


Assuntos
Peixe-Zebra , Proteína rhoA de Ligação ao GTP , Animais , Animais Geneticamente Modificados , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Transdução de Sinais , Peixe-Zebra/genética , Proteína rhoA de Ligação ao GTP/genética , Proteína rhoA de Ligação ao GTP/metabolismo
13.
Oncologist ; 27(7): e561-e570, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35278078

RESUMO

Despite the strong prognostic stratification of circulating tumor cells (CTCs) enumeration in metastatic breast cancer (MBC), current clinical trials usually do not include a baseline CTCs in their design. This study aimed to generate a classifier for CTCs prognostic simulation in existing datasets for hypothesis generation in patients with MBC. A K-nearest neighbor machine learning algorithm was trained on a pooled dataset comprising 2436 individual MBC patients from the European Pooled Analysis Consortium and the MD Anderson Cancer Center to identify patients likely to have CTCs ≥ 5/7 mL blood (StageIVaggressive vs StageIVindolent). The model had a 65.1% accuracy and its prognostic impact resulted in a hazard ratio (HR) of 1.89 (Simulatedaggressive vs SimulatedindolentP < .001), similar to patients with actual CTCs enumeration (HR 2.76; P < .001). The classifier's performance was then tested on an independent retrospective database comprising 446 consecutive hormone receptor (HR)-positive HER2-negative MBC patients. The model further stratified clinical subgroups usually considered prognostically homogeneous such as patients with bone-only or liver metastases. Bone-only disease classified as Simulatedaggressive had a significantly worse overall survival (OS; P < .0001), while patients with liver metastases classified as Simulatedindolent had a significantly better prognosis (P < .0001). Consistent results were observed for patients who had undergone CTCs enumeration in the pooled population. The differential prognostic impact of endocrine- (ET) and chemotherapy (CT) was explored across the simulated subgroups. No significant differences were observed between ET and CT in the overall population, both in terms of progression-free survival (PFS) and OS. In contrast, a statistically significant difference, favoring CT over ET was observed among Simulatedaggressive patients (HR: 0.62; P = .030 and HR: 0.60; P = .037, respectively, for PFS and OS).


Assuntos
Neoplasias da Mama , Ensaios Clínicos como Assunto , Neoplasias Hepáticas , Células Neoplásicas Circulantes , Biomarcadores Tumorais , Simulação por Computador , Feminino , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Células Neoplásicas Circulantes/patologia , Prognóstico , Estudos Retrospectivos
14.
Glob Chang Biol ; 28(15): 4726-4735, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35686571

RESUMO

Many insects are in clear decline, with monarch butterflies (Danaus plexippus) drawing particular attention as a flagship species. It is well documented that, among migratory populations, numbers of overwintering monarchs have been falling across several decades, but trends among breeding monarchs are less clear. Here, we compile >135,000 monarch observations between 1993 and 2018 from the North American Butterfly Association's annual butterfly count to examine spatiotemporal patterns and potential drivers of adult monarch relative abundance trends across the entire breeding range in eastern and western North America. While the data revealed declines at some sites, particularly the US Northeast and parts of the Midwest, numbers in other areas, notably the US Southeast and Northwest, were unchanged or increasing, yielding a slightly positive overall trend across the species range. Negative impacts of agricultural glyphosate use appeared to be counterbalanced by positive effects of annual temperature, particularly in the US Midwest. Overall, our results suggest that population growth in summer is compensating for losses during the winter and that changing environmental variables have offsetting effects on mortality and/or reproduction. We suggest that density-dependent reproductive compensation when lower numbers arrive each spring is currently able to maintain relatively stable breeding monarch numbers. However, we caution against complacency since accelerating climate change may bring growing threats. In addition, increases of summer monarchs in some regions, especially in California and in the south, may reflect replacement of migratory with resident populations. Nonetheless, it is perhaps reassuring that ubiquitous downward trends in summer monarch abundance are not evident.


Assuntos
Borboletas , Migração Animal , Animais , América do Norte , Dinâmica Populacional , Estações do Ano
16.
J Anim Ecol ; 91(4): 780-793, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35174493

RESUMO

Insect-pathogen dynamics can show seasonal and inter-annual variations that covary with fluctuations in insect abundance and climate. Long-term analyses are especially needed to track parasite dynamics in migratory insects, in part because their vast habitat ranges and high mobility might dampen local effects of density and climate on infection prevalence. Monarch butterflies Danaus plexippus are commonly infected with the protozoan Ophryocystis elektroscirrha (OE). Because this parasite lowers monarch survival and flight performance, and because migratory monarchs have experienced declines in recent decades, it is important to understand the patterns and drivers of infection. Here we compiled data on OE infection spanning 50 years, from wild monarchs sampled in the United States, Canada and Mexico during summer breeding, fall migrating and overwintering periods. We examined eastern versus western North American monarchs separately, to ask how abundance estimates, resource availability, climate and breeding season length impact infection trends. We further assessed the intensity of migratory culling, which occurs when infected individuals are removed from the population during migration. Average infection prevalence was four times higher in western compared to eastern subpopulations. In eastern North America, the proportion of infected monarchs increased threefold since the mid-2000s. In the western region, the proportion of infected monarchs declined sharply from 2000 to 2015, and increased thereafter. For both eastern and western subpopulations, years with greater summer adult abundance predicted greater infection prevalence, indicating that transmission increases with host breeding density. Environmental variables (temperature and NDVI) were not associated with changes in the proportion of infected adults. We found evidence for migratory culling of infected butterflies, based on declines in parasitism during fall migration. We estimated that tens of millions fewer monarchs reach overwintering sites in Mexico as a result of OE, highlighting the need to consider the parasite as a potential threat to the monarch population. Increases in infection among eastern North American monarchs post-2002 suggest that changes to the host's ecology or environment have intensified parasite transmission. Further work is needed to examine the degree to which human practices, such as mass caterpillar rearing and the widespread planting of exotic milkweed, have contributed to this trend.


Assuntos
Borboletas , Parasitos , Migração Animal , Animais , Borboletas/parasitologia , México , Melhoramento Vegetal , Estações do Ano , Estados Unidos
17.
Biol Lett ; 18(6): 20220183, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35765809

RESUMO

Biodiversity is measured from various perspectives. One of them, functional diversity, quantifies the heterogeneity in species traits and roles in an ecosystem. One important aspect of species roles is their interactions with other species, i.e. their network role. We therefore investigate here functional diversity from the network perspective. Species differ in their network positions in a food web, having different interaction patterns. We developed a measure for quantifying the diversity in species interaction patterns in a food web. We examined the relationship between interaction diversity and several global network properties for 92 food webs. Our results showed that high interaction diversity occurs in sparsely connected and less cohesive food webs. High interaction diversity also occurred in food webs with more clusters and high network modularity. We also quantified several conventional functional diversity indices and demonstrate that they show little or no correlation with interaction diversity. Our proposed diversity index therefore provides a measure complementary to current concepts of functional diversity.


Assuntos
Ecossistema , Cadeia Alimentar , Biodiversidade
18.
Oncology (Williston Park) ; 36(2): 84-91, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35180340

RESUMO

INTRODUCTION: Financial conflicts of interest (COIs) represent a common and complex issue in hematology and oncology. However, little is known about the timing of when COIs begin to develop during a career trajectory. We evaluated self-reported COIs for junior faculty members at top cancer centers to determine how these financial relationships correlated with measures of academic career productivity. METHODS: We analyzed data from 230 assistant professors at 10 academic cancer centers. Financial COIs were identified from the CMS Open Payments (Sunshine Act dollars) database. Self-reported COIs were obtained from American Society of Clinical Oncology (ASCO) and American Society of Hematology (ASH) disclosures, and from disclosures in recent publications. Number of publications and h-index (defined as the largest number of publications [h] such that h publications each have at least h citations) were used as measures of academic productivity. Scatter plots and Spearman correlation coefficients were used to assess the relationship between COIs or Sunshine Act dollars with number of publications and h-index. Linear regression modeling was used to analyze the relationships between COIs or Sunshine Act dollars with number of publications and h-index, adjusting for years of experience since completing fellowship (YSF). RESULTS: A total of 46% of junior faculty had at least 1 COI. Number of COIs reported to ASCO/ASH was positively correlated with total Sunshine Act dollars (Spearman correlation, 0.53; P <.01). The number of COIs and the number of Sunshine Act dollars increased with years in practice (Spearman correlation, 0.38 and 0.25, respectively; P <.01 for both). COIs and Sunshine Act dollars correlated with h-index (Spearman correlation, 0.41 and 0.37, respectively; both P <.01). After adjusting for YSF, linear regression demonstrated that log-transformed h-index and number of publications were associated with Sunshine Act dollars (both P <.01) and COIs (ASCO/ASH) (both P = .01). CONCLUSIONS: Financial COIs increased with number of YSF. Measures of academic productivity were positively correlated with COIs (ASCO/ASH) and Sunshine Act dollars. These data suggest that the cultivation of industry relationships is associated with the early academic productivity of junior faculty.


Assuntos
Conflito de Interesses/economia , Docentes de Medicina/estatística & dados numéricos , Hematologia , Enfermagem Oncológica , Publicações/estatística & dados numéricos , Centros Médicos Acadêmicos , Pesquisa Biomédica/economia , Conflito de Interesses/legislação & jurisprudência , Estudos Transversais , Bases de Dados Factuais , Feminino , Humanos , Masculino , Fatores de Tempo , Estados Unidos
19.
Proc Natl Acad Sci U S A ; 116(23): 11470-11479, 2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-31113879

RESUMO

Germination of Bacillus spores is induced by the interaction of specific nutrient molecules with germinant receptors (GRs) localized in the spore's inner membrane. GRs typically consist of three subunits referred to as A, B, and C, although functions of individual subunits are not known. Here we present the crystal structure of the N-terminal domain (NTD) of the A subunit of the Bacillus megaterium GerK3 GR, revealing two distinct globular subdomains bisected by a cleft, a fold with strong homology to substrate-binding proteins in bacterial ABC transporters. Molecular docking, chemical shift perturbation measurement, and mutagenesis coupled with spore germination analyses support a proposed model that the interface between the two subdomains in the NTD of GR A subunits serves as the germinant binding site and plays a critical role in spore germination. Our findings provide a conceptual framework for understanding the germinant recruitment mechanism by which GRs trigger spore germination.


Assuntos
Bacillus megaterium/metabolismo , Proteínas de Bactérias/metabolismo , Subunidades Proteicas/metabolismo , Esporos Bacterianos/metabolismo , Simulação de Acoplamento Molecular , Domínios Proteicos
20.
Clin Diabetes ; 40(3): 366-369, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35983427

RESUMO

Quality Improvement Success Stories are published by the American Diabetes Association in collaboration with the American College of Physicians and the National Diabetes Education Program. This series is intended to highlight best practices and strategies from programs and clinics that have successfully improved the quality of care for people with diabetes or related conditions. Each article in the series is reviewed and follows a standard format developed by the editors of Clinical Diabetes. The following article describes an effort to reduce iatrogenic insulin-associated hypoglycemia at the University of Chicago Medical Center in Chicago, IL.

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