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1.
CA Cancer J Clin ; 70(6): 480-504, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32910493

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has given rise to a pandemic of unprecedented proportions in the modern era because of its highly contagious nature and impact on human health and society: coronavirus disease 2019 (COVID-19). Patients with cardiovascular (CV) risk factors and established CV disease (CVD) are among those initially identified at the highest risk for serious complications, including death. Subsequent studies have pointed out that patients with cancer are also at high risk for a critical disease course. Therefore, the most vulnerable patients are seemingly those with both cancer and CVD, and a careful, unified approach in the evaluation and management of this patient population is especially needed in times of the COVID-19 pandemic. This review provides an overview of the unique implications of the viral outbreak for the field of cardio-oncology and outlines key modifications in the approach to this ever-increasing patient population. These modifications include a shift toward greater utilization of cardiac biomarkers and a more focused CV imaging approach in the broader context of modifications to typical practice pathways. The goal of this strategic adjustment is to minimize the risk of SARS-CoV-2 infection (or other future viral outbreaks) while not becoming negligent of CVD and its important impact on the overall outcomes of patients who are being treated for cancer.


Assuntos
Antineoplásicos/efeitos adversos , COVID-19/complicações , Doenças Cardiovasculares/etiologia , Infecção Hospitalar/prevenção & controle , Neoplasias/complicações , Neoplasias/terapia , Antraciclinas/efeitos adversos , COVID-19/fisiopatologia , COVID-19/prevenção & controle , COVID-19/transmissão , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/terapia , Humanos , Inibidores de Proteassoma/efeitos adversos , Inibidores de Proteínas Quinases/efeitos adversos , Radioterapia/efeitos adversos , Receptor ErbB-2/antagonistas & inibidores , Encaminhamento e Consulta , SARS-CoV-2 , Trastuzumab/efeitos adversos
2.
PLoS Comput Biol ; 20(6): e1011912, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38843301

RESUMO

To standardize metabolomics data analysis and facilitate future computational developments, it is essential to have a set of well-defined templates for common data structures. Here we describe a collection of data structures involved in metabolomics data processing and illustrate how they are utilized in a full-featured Python-centric pipeline. We demonstrate the performance of the pipeline, and the details in annotation and quality control using large-scale LC-MS metabolomics and lipidomics data and LC-MS/MS data. Multiple previously published datasets are also reanalyzed to showcase its utility in biological data analysis. This pipeline allows users to streamline data processing, quality control, annotation, and standardization in an efficient and transparent manner. This work fills a major gap in the Python ecosystem for computational metabolomics.


Assuntos
Metabolômica , Software , Metabolômica/métodos , Metabolômica/estatística & dados numéricos , Biologia Computacional/métodos , Lipidômica/métodos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Linguagens de Programação , Humanos
3.
J Am Chem Soc ; 146(14): 9499-9505, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38522088

RESUMO

Herein, we report that readily accessible azoxy-triazenes can serve as nitrogen atom sources under visible light excitation for the phthalimido-protected aziridination of alkenes. This approach eliminates the need for external oxidants, precious transition metals, and photocatalysts, marking a departure from conventional methods. The versatility of this transformation extends to the selective aziridination of both activated and unactivated multisubstituted alkenes of varying electronic profiles. Notably, this process avoids the formation of competing C-H insertion products. The described protocol is operationally simple, scalable, and adaptable to photoflow conditions. Mechanistic studies support the idea that the photofragmentation of azoxy-triazenes results in the generation of a free singlet nitrene. Furthermore, a mild photoredox-catalyzed N-N cleavage of the protecting group to furnish the free aziridines is reported. Our findings contribute to the advancement of sustainable and practical methodologies for the synthesis of nitrogen-containing compounds, showcasing the potential for broader applications in synthetic chemistry.

4.
J Biol Chem ; 298(7): 102127, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35709986

RESUMO

The evolution of multidrug resistance in Acinetobacter spp. increases the risk of our best antibiotics losing their efficacy. From a clinical perspective, the carbapenem-hydrolyzing class D ß-lactamase subfamily present in Acinetobacter spp. is particularly concerning because of its ability to confer resistance to carbapenems. The kinetic profiles of class D ß-lactamases exhibit variability in carbapenem hydrolysis, suggesting functional differences. To better understand the structure-function relationship between the carbapenem-hydrolyzing class D ß-lactamase OXA-24/40 found in Acinetobacter baumannii and carbapenem substrates, we analyzed steady-state kinetics with the carbapenem antibiotics meropenem and ertapenem and determined the structures of complexes of OXA-24/40 bound to imipenem, meropenem, doripenem, and ertapenem, as well as the expanded-spectrum cephalosporin cefotaxime, using X-ray crystallography. We show that OXA-24/40 exhibits a preference for ertapenem compared with meropenem, imipenem, and doripenem, with an increase in catalytic efficiency of up to fourfold. We suggest that superposition of the nine OXA-24/40 complexes will better inform future inhibitor design efforts by providing insight into the complicated and varying ways in which carbapenems are selected and bound by class D ß-lactamases.


Assuntos
Proteínas de Bactérias , Carbapenêmicos , beta-Lactamases , Acinetobacter baumannii/enzimologia , Antibacterianos/química , Antibacterianos/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Carbapenêmicos/química , Carbapenêmicos/metabolismo , Hidrólise , Testes de Sensibilidade Microbiana , Conformação Proteica , Especificidade por Substrato , beta-Lactamases/química , beta-Lactamases/metabolismo
5.
J Card Fail ; 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37907148

RESUMO

BACKGROUND: CARS (Cardiac Amyloidosis Registry Study) is a multicenter registry established in 2019 that includes patients with transthyretin (ATTR, wild-type and variant) and light chain (AL) cardiac amyloidosis (CA) evaluated at major amyloidosis centers between 1997 and 2025. CARS aims to describe the natural history of CA with attention to clinical and diagnostic variables at the time of diagnosis, real-world treatment patterns, and associated outcomes of patients in a diverse cohort that is more representative of the at-risk population than that described in CA clinical trials. METHODS AND RESULTS: This article describes the design and methodology of CARS, including procedures for data collection and preliminary results. As of February 2023, 20 centers in the United States enrolled 1415 patients, including 1155 (82%) with ATTR and 260 (18%) with AL CA. Among those with ATTR, wild-type is the most common ATTR (71%), and most of the 305 patients with variant ATTR have the p.V142I mutation (68%). A quarter of the total population identifies as Black. More individuals with AL are female (39%) compared to those with ATTR (13%). CONCLUSIONS: CARS will answer crucial clinical questions about CA natural history and permit comparison of different therapeutics not possible through current clinical trials. Future international collaboration will further strengthen the validity of observations of this increasingly recognized condition.

6.
J Natl Compr Canc Netw ; 21(10): 1039-1049.e10, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37856199

RESUMO

BACKGROUND: Although VEGFR tyrosine kinase inhibitors (TKIs) are a preferred systemic treatment approach for patients with advanced renal cell carcinoma (RCC) and thyroid carcinoma (TC), treatment-related cardiovascular (CV) toxicity is an important contributor to morbidity. However, the clinical risk assessment and impact of CV toxicities, including early significant hypertension, among real-world advanced cancer populations receiving VEGFR TKI therapies remain understudied. METHODS: In a multicenter, retrospective cohort study across 3 large and diverse US health systems, we characterized baseline hypertension and CV comorbidity in patients with RCC and those with TC who are newly initiating VEGFR TKI therapy. We also evaluated baseline patient-, treatment-, and disease-related factors associated with the risk for treatment-related early hypertension (within 6 weeks of TKI initiation) and major adverse CV events (MACE), accounting for the competing risk of death in an advanced cancer population, after VEGFR TKI initiation. RESULTS: Between 2008 and 2020, 987 patients (80.3% with RCC, 19.7% with TC) initiated VEGFR TKI therapy. The baseline prevalence of hypertension was high (61.5% and 53.6% in patients with RCC and TC, respectively). Adverse CV events, including heart failure and cerebrovascular accident, were common (occurring in 14.9% of patients) and frequently occurred early (46.3% occurred within 1 year of VEGFR TKI initiation). Baseline hypertension and Black race were the primary clinical factors associated with increased acute hypertensive risk within 6 weeks of VEGFR TKI initiation. However, early significant "on-treatment" hypertension was not associated with MACE. CONCLUSIONS: These multicenter, real-world findings indicate that hypertensive and CV morbidities are highly prevalent among patients initiating VEGFR TKI therapies, and baseline hypertension and Black race represent the primary clinical factors associated with VEGFR TKI-related early significant hypertension. However, early on-treatment hypertension was not associated with MACE, and cancer-specific CV risk algorithms may be warranted for patients initiating VEGFR TKIs.


Assuntos
Carcinoma de Células Renais , Hipertensão , Neoplasias Renais , Neoplasias da Glândula Tireoide , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/epidemiologia , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/epidemiologia , Pressão Sanguínea , Estudos Retrospectivos , Inibidores de Proteínas Quinases/efeitos adversos , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/epidemiologia , Hipertensão/induzido quimicamente , Hipertensão/epidemiologia , Hipertensão/tratamento farmacológico
7.
J Org Chem ; 88(1): 717-721, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36525632

RESUMO

We report a photoinduced phenanthrene synthesis from aryl iodides and styrenes through an arylation/cyclization cascade. Compared to prior methods, this approach obviates the need for hazardous reagents and provides access to unsymmetrical phenanthrenes with good functional group tolerance. Mechanistic studies revealed that photoexcitation of aryl iodides leads to homolytic C-I bond cleavage. Arylation of styrenes with the formed aryl radical species furnishes stilbene derivatives, which undergo photoinduced cyclization promoted by iodine generated in situ to yield phenanthrene products.


Assuntos
Iodetos , Fenantrenos , Estrutura Molecular , Fenantrenos/química , Estirenos/química
8.
Nephrology (Carlton) ; 28(3): 168-174, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36573826

RESUMO

AIM: Heparin induced thrombocytopenia (HIT) and end stage kidney disease (ESKD) are independent conditions associated with increased mortality and morbidity, however, whether ESKD is an independent risk factor for increased mortality in HIT admissions is not well studied. Therefore, we aimed to compare in-hospital mortality in HIT admissions based on their ESKD status. METHODS: This is a retrospective cohort study of HIT hospitalizations aged 18 and older using the 2016-2019 national inpatient sample (NIS) database. RESULTS: From 2016 to 2019 we had 12 161 admissions for HIT among 28 484 087 total hospitalizations. The annual incidence rate for HIT admissions per 100 000 admissions were: 47, 46, 41.1, and 36.6, respectively (p < .001) in 2016, 2017, 2018, and 2019 respectively. Among HIT admissions, the mean age was 64.3 years, 46.8% were females, 68% were Whites and 16% were Blacks. Black patients have a significantly higher likelihood of in-hospital mortality than White patients (aOR 1.25; 95% CI: 1.06, 1.48; p = .007). Patients who did not have any insurance or self-pay had higher mortality compared to Medicare (aOR 1.64; 95% CI: 1.13, 2.38; p = .009). ESKD status was not associated with higher or lower in-hospital mortality among HIT admissions (aOR 1.002; 95% CI: 0.84, 1.19; p = .981) after adjusting for age, sex, race, and insurance status. CONCLUSION: There are no higher or lower odds of in-hospital mortality in the ESKD subgroup in HIT admissions in adults. Decreasing incidence of HIT hospitalizations was seen over the years from 2016 to 2019.


Assuntos
Falência Renal Crônica , Trombocitopenia , Adulto , Feminino , Humanos , Idoso , Estados Unidos , Pessoa de Meia-Idade , Masculino , Estudos Retrospectivos , Estudos de Coortes , Mortalidade Hospitalar , Medicare , Heparina/efeitos adversos
9.
Curr Cardiol Rep ; 25(11): 1589-1600, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37796395

RESUMO

PURPOSE OF REVIEW: Radiation is foundational to the treatment of cancer and improves overall survival. Yet, it is important to recognize the potential cardiovascular effects of radiation therapy and how to best minimize or manage them. Screening-both through imaging and with biomarkers-can potentially identify cardiovascular effects early, allowing for prompt initiation of treatment to mitigate late effects. RECENT FINDINGS: Cardiac echocardiography, magnetic resonance imaging (MRI), computed tomography, and measurements of troponin and natriuretic peptides serve as the initial screening tests of choice for RICD. Novel imaging applications, including positron emission tomography and specific MRI parameters, and biomarker testing, including myeloperoxidase, growth differentiation factor 15, galectin 3, micro-RNA, and metabolomics, hold promise for earlier detection and more specific characterization of RICD. Advances in imaging and novel applications of biomarkers have potential to identify subclinical RICD and may reveal opportunities for early intervention. Further research is needed to elucidate optimal imaging screening modalities, biomarkers, and surveillance strategies.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Cardiotoxicidade/diagnóstico por imagem , Cardiotoxicidade/etiologia , Detecção Precoce de Câncer , Neoplasias/radioterapia , Neoplasias/tratamento farmacológico , Biomarcadores , Ecocardiografia , Antineoplásicos/uso terapêutico
10.
Curr Cardiol Rep ; 25(3): 133-146, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36790618

RESUMO

PURPOSE OF REVIEW: Following significant advancements in cancer therapeutics and survival, the risk of cancer therapy-related cardiotoxicity (CTRC) is increasingly recognized. With ongoing efforts to reduce cardiovascular morbidity and mortality in cancer patients and survivors, cardiac biomarkers have been studied for both risk stratification and monitoring during and after therapy to detect subclinical disease. This article will review the utility for biomarker use throughout the cancer care continuum. RECENT FINDINGS: A recent meta-analysis shows utility for troponin in monitoring patients at risk for CTRC during cancer therapy. The role for natriuretic peptides is less clear but may be useful in patients receiving proteasome inhibitors. Early studies explore use of myeloperoxidase, growth differentiation factor 15, galectin 3, micro-RNA, and others as novel biomarkers in CTRC. Biomarkers have potential to identify subclinical CTRC and may reveal opportunities for early intervention. Further research is needed to elucidate optimal biomarkers and surveillance strategies.


Assuntos
Antineoplásicos , Cardiopatias , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/induzido quimicamente , Biomarcadores , Oncologia , Cardiopatias/induzido quimicamente , Cardiopatias/diagnóstico , Cardiotoxicidade/diagnóstico , Medição de Risco , Antineoplásicos/efeitos adversos
11.
Eur Heart J ; 43(4): 280-299, 2022 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-34904661

RESUMO

The discipline of Cardio-Oncology has seen tremendous growth over the past decade. It is devoted to the cardiovascular (CV) care of the cancer patient, especially to the mitigation and management of CV complications or toxicities of cancer therapies, which can have profound implications on prognosis. To that effect, many studies have assessed CV toxicities in patients undergoing various types of cancer therapies; however, direct comparisons have proven difficult due to lack of uniformity in CV toxicity endpoints. Similarly, in clinical practice, there can be substantial differences in the understanding of what constitutes CV toxicity, which can lead to significant variation in patient management and outcomes. This document addresses these issues and provides consensus definitions for the most commonly reported CV toxicities, including cardiomyopathy/heart failure and myocarditis, vascular toxicity, and hypertension, as well as arrhythmias and QTc prolongation. The current document reflects a harmonizing review of the current landscape in CV toxicities and the definitions used to define these. This consensus effort aims to provide a structure for definitions of CV toxicity in the clinic and for future research. It will be important to link the definitions outlined herein to outcomes in clinical practice and CV endpoints in clinical trials. It should facilitate communication across various disciplines to improve clinical outcomes for cancer patients with CV diseases.


Assuntos
Antineoplásicos , Doenças Cardiovasculares , Cardiopatias , Neoplasias , Antineoplásicos/efeitos adversos , Doenças Cardiovasculares/complicações , Cardiopatias/complicações , Humanos , Oncologia , Neoplasias/tratamento farmacológico
12.
J Chem Inf Model ; 62(22): 5622-5633, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-36351167

RESUMO

The development of accurate transferable force fields is key to realizing the full potential of atomistic modeling in the study of biological processes such as protein-ligand binding for drug discovery. State-of-the-art transferable force fields, such as those produced by the Open Force Field Initiative, use modern software engineering and automation techniques to yield accuracy improvements. However, force field torsion parameters, which must account for many stereoelectronic and steric effects, are considered to be less transferable than other force field parameters and are therefore often targets for bespoke parametrization. Here, we present the Open Force Field QCSubmit and BespokeFit software packages that, when combined, facilitate the fitting of torsion parameters to quantum mechanical reference data at scale. We demonstrate the use of QCSubmit for simplifying the process of creating and archiving large numbers of quantum chemical calculations, by generating a dataset of 671 torsion scans for druglike fragments. We use BespokeFit to derive individual torsion parameters for each of these molecules, thereby reducing the root-mean-square error in the potential energy surface from 1.1 kcal/mol, using the original transferable force field, to 0.4 kcal/mol using the bespoke version. Furthermore, we employ the bespoke force fields to compute the relative binding free energies of a congeneric series of inhibitors of the TYK2 protein, and demonstrate further improvements in accuracy, compared to the base force field (MUE reduced from 0.560.390.77 to 0.420.280.59 kcal/mol and R2 correlation improved from 0.720.350.87 to 0.930.840.97).


Assuntos
Proteínas , Software , Ligantes , Proteínas/química , Entropia , Ligação Proteica
13.
Curr Treat Options Oncol ; 23(10): 1388-1404, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36087234

RESUMO

OPINION STATEMENT: Several seminal papers over the last decade have furthered our recognition of radiation-induced heart disease (RIHD) as an important potential toxicity following radiation therapy (RT) to the chest. Investigators continue to evaluate the subacute and long-term effects of RT. In addition, studies are determining whether certain cardiac substructures are more sensitive to radiation, working to identify risk factors for the development of RIHD, and testing screening and mitigation strategies for RIHD. Multiple groups and expert consensus guidelines have published whole-heart and cardiac substructure dose constraints based on available data and cancer type. The authors recommend readers to familiarize themselves with the guidelines for screening and mitigating RIHD in adults and children, which advocate for cardiovascular risk assessment and reduction before and following RT, as well as cardiovascular imaging at appropriate follow-up intervals for early recognition of subclinical cardiovascular disease. Referrals to cardiology or cardio-oncology can also be helpful in prevention, screening, and mitigation strategies.


Assuntos
Doenças Cardiovasculares , Cardiopatias , Neoplasias , Lesões por Radiação , Adulto , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Criança , Coração/efeitos da radiação , Cardiopatias/diagnóstico , Humanos , Neoplasias/diagnóstico , Neoplasias/etiologia , Neoplasias/radioterapia , Lesões por Radiação/diagnóstico , Lesões por Radiação/epidemiologia , Lesões por Radiação/etiologia
14.
Heart Fail Clin ; 18(3): 403-413, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35718415

RESUMO

Radiation therapy (RT) is part of standard-of-care treatment of many thoracic cancers. More than 60% of patients receiving thoracic RT may eventually develop radiation-induced cardiac dysfunction (RICD) secondary to collateral heart dose. This article reviews factors contributing to a thoracic cancer patient's risk for RICD, including RT dose to the heart and/or cardiac substructures, other anticancer treatments, and a patient's cardiometabolic health. It is also discussed how automated tracking of these factors within electronic medical record environments may aid radiation oncologists and other treating physicians in their ability to prevent, detect, and/or treat RICD in this expanding patient population.


Assuntos
Cardiopatias , Planejamento da Radioterapia Assistida por Computador , Coração , Cardiopatias/etiologia , Cardiopatias/prevenção & controle , Humanos
15.
Nat Chem Biol ; 14(9): 861-869, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30061718

RESUMO

Fluorescent sensors are an essential part of the experimental toolbox of the life sciences, where they are used ubiquitously to visualize intra- and extracellular signaling. In the brain, optical neurotransmitter sensors can shed light on temporal and spatial aspects of signal transmission by directly observing, for instance, neurotransmitter release and spread. Here we report the development and application of the first optical sensor for the amino acid glycine, which is both an inhibitory neurotransmitter and a co-agonist of the N-methyl-D-aspartate receptors (NMDARs) involved in synaptic plasticity. Computational design of a glycine-specific binding protein allowed us to produce the optical glycine FRET sensor (GlyFS), which can be used with single and two-photon excitation fluorescence microscopy. We took advantage of this newly developed sensor to test predictions about the uneven spatial distribution of glycine in extracellular space and to demonstrate that extracellular glycine levels are controlled by plasticity-inducing stimuli.


Assuntos
Corantes Fluorescentes/química , Glicina/análise , Hipocampo/química , Animais , Células Cultivadas , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/síntese química , Células HEK293 , Humanos , Masculino , Imagem Óptica , Ratos , Ratos Wistar
16.
Anal Chem ; 91(14): 8933-8940, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31260262

RESUMO

Improvements in Fourier transform mass spectrometry (FT-MS) enable increasingly more complex experiments in the field of metabolomics. What is directly detected in FT-MS spectra are spectral features (peaks) that correspond to sets of adducted and charged forms of specific molecules in the sample. The robust assignment of these features is an essential step for MS-based metabolomics experiments, but the sheer complexity of what is detected and a variety of analytically introduced variance, errors, and artifacts has hindered the systematic analysis of complex patterns of observed peaks with respect to isotope content. We have developed a method called SMIRFE that detects small biomolecules and determines their elemental molecular formula (EMF) using detected sets of isotopologue peaks sharing the same EMF. SMIRFE does not use a database of known metabolite formulas; instead a nearly comprehensive search space of all isotopologues within a mass range is constructed and used for assignment. This search space can be tailored for different isotope labeling patterns expected in different stable isotope tracing experiments. Using consumer-level computing equipment, a large search space of 2000 Da was constructed, and assignment performance was evaluated and validated using verified assignments on a pair of peak lists derived from spectra containing unlabeled and 15N-labeled versions of amino acids derivatized using ethylchloroformate. SMIRFE identified 18 of 18 predicted derivatized EMFs, and each assignment was evaluated statistically and assigned an e-value representing the probability to occur by chance.


Assuntos
Aminoácidos/análise , Espectrometria de Massas/métodos , Algoritmos , Isótopos de Carbono/análise , Análise de Fourier , Marcação por Isótopo/métodos , Metabolômica/métodos , Isótopos de Nitrogênio/análise
17.
PLoS Pathog ; 13(7): e1006469, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28759640

RESUMO

The repeat region of the Plasmodium falciparum circumsporozoite protein (CSP) is a major vaccine antigen because it can be targeted by parasite neutralizing antibodies; however, little is known about this interaction. We used isothermal titration calorimetry, X-ray crystallography and mutagenesis-validated modeling to analyze the binding of a murine neutralizing antibody to Plasmodium falciparum CSP. Strikingly, we found that the repeat region of CSP is bound by multiple antibodies. This repeating pattern allows multiple weak interactions of single FAB domains to accumulate and yield a complex with a dissociation constant in the low nM range. Because the CSP protein can potentially cross-link multiple B cell receptors (BCRs) we hypothesized that the B cell response might be T cell independent. However, while there was a modest response in mice deficient in T cell help, the bulk of the response was T cell dependent. By sequencing the BCRs of CSP-repeat specific B cells in inbred mice we found that these cells underwent somatic hypermutation and affinity maturation indicative of a T-dependent response. Last, we found that the BCR repertoire of responding B cells was limited suggesting that the structural simplicity of the repeat may limit the breadth of the immune response.


Assuntos
Anticorpos Antiprotozoários/imunologia , Linfócitos B/imunologia , Vacinas Antimaláricas/imunologia , Plasmodium falciparum/imunologia , Proteínas de Protozoários/imunologia , Linfócitos T/imunologia , Animais , Afinidade de Anticorpos , Cristalografia por Raios X , Feminino , Humanos , Vacinas Antimaláricas/administração & dosagem , Vacinas Antimaláricas/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Plasmodium falciparum/química , Plasmodium falciparum/genética , Proteínas de Protozoários/administração & dosagem , Proteínas de Protozoários/química , Proteínas de Protozoários/genética
18.
Metabolomics ; 14(10): 125, 2018 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-30830442

RESUMO

INTRODUCTION: Direct injection Fourier-transform mass spectrometry (FT-MS) allows for the high-throughput and high-resolution detection of thousands of metabolite-associated isotopologues. However, spectral artifacts can generate large numbers of spectral features (peaks) that do not correspond to known compounds. Misassignment of these artifactual features creates interpretive errors and limits our ability to discern the role of representative features within living systems. OBJECTIVES: Our goal is to develop rigorous methods that identify and handle spectral artifacts within the context of high-throughput FT-MS-based metabolomics studies. RESULTS: We observed three types of artifacts unique to FT-MS that we named high peak density (HPD) sites: fuzzy sites, ringing and partial ringing. While ringing artifacts are well-known, fuzzy sites and partial ringing have not been previously well-characterized in the literature. We developed new computational methods based on comparisons of peak density within a spectrum to identify regions of spectra with fuzzy sites. We used these methods to identify and eliminate fuzzy site artifacts in an example dataset of paired cancer and non-cancer lung tissue samples and evaluated the impact of these artifacts on classification accuracy and robustness. CONCLUSION: Our methods robustly identified consistent fuzzy site artifacts in our FT-MS metabolomics spectral data. Without artifact identification and removal, 91.4% classification accuracy was achieved on an example lung cancer dataset; however, these classifiers rely heavily on artifactual features present in fuzzy sites. Proper removal of fuzzy site artifacts produces a more robust classifier based on non-artifactual features, with slightly improved accuracy of 92.4% in our example analysis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Análise de Fourier , Ensaios de Triagem em Larga Escala , Neoplasias Pulmonares/metabolismo , Pulmão/metabolismo , Espectrometria de Massas , Metabolômica , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Humanos , Neoplasias Pulmonares/diagnóstico
20.
Knee Surg Sports Traumatol Arthrosc ; 24(3): 715-22, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26506845

RESUMO

PURPOSE: Knowledge of epidemiologic trends of meniscal injuries in young active populations is limited. Better awareness of injury patterns is a first step to lowering injury rates. Our hypothesis was that meniscal injuries in high school athletes would vary by gender, sport, and type of exposure. METHODS: During the 2007/2008 and 2012/2013 academic years, a large nationally disperse sample of US high schools reported athlete exposure and injury data for 22 sports by having certified athletic trainers complete an internet-based data collection tool. RESULTS: One thousand and eighty-two meniscal injuries were reported during 21,088,365 athlete exposures for an overall injury rate of 5.1 per 100,000 athlete exposures. The overall rate of injury was higher in competition (11.9) than practice (2.7) (RR = 4.4; 95% CI 3.9-5.0), and 12/19 sports showed significantly higher injury rates in competition compared to practice. Of all injuries, 68.0% occurred in boys, yet among the gender-comparable sports of soccer, basketball, track and field, lacrosse, and baseball/softball injury rates were higher for girls than boys (5.5 and 2.5, respectively, RR = 2.2; 95% CI 1.8-2.7). Contact injury represented the most common mechanism (55.9%). Surgery was performed for the majority of injuries (63.8%), and 54.0% of athletes had associated intra-articular knee pathology. CONCLUSIONS: Meniscal injury patterns among high school athletes vary by gender, sport, and type of exposure. Our study is clinically relevant because recognition of distinct differences in these injury patterns will help drive evidence-based, targeted injury prevention strategies and efforts. LEVEL OF EVIDENCE: III.


Assuntos
Traumatismos em Atletas/epidemiologia , Lesões do Menisco Tibial , Adolescente , Traumatismos em Atletas/cirurgia , Feminino , Humanos , Masculino , Meniscos Tibiais/cirurgia , Instituições Acadêmicas , Distribuição por Sexo , Estados Unidos/epidemiologia
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