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1.
Immunity ; 49(1): 178-193.e7, 2018 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-29958801

RESUMO

The biological and functional heterogeneity between tumors-both across and within cancer types-poses a challenge for immunotherapy. To understand the factors underlying tumor immune heterogeneity and immunotherapy sensitivity, we established a library of congenic tumor cell clones from an autochthonous mouse model of pancreatic adenocarcinoma. These clones generated tumors that recapitulated T cell-inflamed and non-T-cell-inflamed tumor microenvironments upon implantation in immunocompetent mice, with distinct patterns of infiltration by immune cell subsets. Co-injecting tumor cell clones revealed the non-T-cell-inflamed phenotype is dominant and that both quantitative and qualitative features of intratumoral CD8+ T cells determine response to therapy. Transcriptomic and epigenetic analyses revealed tumor-cell-intrinsic production of the chemokine CXCL1 as a determinant of the non-T-cell-inflamed microenvironment, and ablation of CXCL1 promoted T cell infiltration and sensitivity to a combination immunotherapy regimen. Thus, tumor cell-intrinsic factors shape the tumor immune microenvironment and influence the outcome of immunotherapy.


Assuntos
Adenocarcinoma/terapia , Fatores Imunológicos/imunologia , Imunoterapia , Subpopulações de Linfócitos/imunologia , Linfócitos do Interstício Tumoral/imunologia , Neoplasias Pancreáticas/terapia , Microambiente Tumoral/imunologia , Adenocarcinoma/imunologia , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Animais , Linfócitos T CD8-Positivos/imunologia , Epigenômica , Feminino , Perfilação da Expressão Gênica , Humanos , Fatores Imunológicos/genética , Masculino , Camundongos , Pessoa de Meia-Idade , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/patologia , Cultura Primária de Células , Neoplasias Pancreáticas
2.
Am J Pathol ; 194(10): 1986-1996, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39069167

RESUMO

Phosphoinositide 3-kinase (PI3K)-AKT and androgen receptor (AR) pathways are commonly activated in prostate cancers. Their reciprocal regulation makes advanced prostate cancers difficult to treat. The current study shows that pleckstrin-2 (PLEK2), a proto-oncoprotein involved in the activation and stabilization of AKT, connects these two pathways. Genetic evidence provided herein suggests that Plek2 deficiency largely reverted tumorigenesis in Pten prostate-specific knockout mice and that overexpression of PLEK2 promoted the proliferation and colony formation of prostate cancer cells in vitro. In addition, PLEK2 was negatively regulated by AR, AR transcriptionally repressed PLEK2 through binding to the PLEK2 promoter region, and overexpression of AR reduced PLEK2 expression, which inactivated AKT. Conversely, knockdown of AR in prostate cancer cells increased PLEK2 expression and activated the AKT pathway. This reciprocal inhibitory loop can be pharmacologically targeted using the PLEK2 inhibitor. PLEK2 inhibitor dose-dependently inhibited prostate cancer cell proliferation with the inactivation of AKT. Overall, the current study uncovered a crucial role of PLEK2 in prostate cancer proliferation and provided the rationale for targeting PLEK2 to treat prostate cancers.


Assuntos
Proliferação de Células , Proteínas de Membrana , Neoplasias da Próstata , Proteínas Proto-Oncogênicas c-akt , Receptores Androgênicos , Animais , Humanos , Masculino , Camundongos , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Camundongos Knockout , Neoplasias da Próstata/patologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Androgênicos/metabolismo , Transdução de Sinais , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo
3.
Stat Med ; 42(12): 1965-1980, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-36896833

RESUMO

Hypertension significantly increases the risk for many health conditions including heart disease and stroke. Hypertensive patients often have continuous measurements of their blood pressure to better understand how it fluctuates over the day. The continuous-time Markov chain (CTMC) is commonly used to study repeated measurements with categorical outcomes. However, the standard CTMC may be restrictive, because the rates of transitions between states are assumed to be constant through time, while the transition rates for describing the dynamics of hypertension are likely to be changing over time. In addition, the applications of CTMC rarely account for the effects of other covariates on state transitions. In this article, we considered a non-homogeneous continuous-time Markov chain with two states to analyze changes in hypertension while accounting for multiple covariates. The explicit formulas for the transition probability matrix as well as the corresponding likelihood function were derived. In addition, we proposed a maximum likelihood estimation algorithm for estimating the parameters in the time-dependent rate function. Lastly, the model performance was demonstrated through both a simulation study and application to ambulatory blood pressure data.


Assuntos
Monitorização Ambulatorial da Pressão Arterial , Hipertensão , Humanos , Cadeias de Markov , Funções Verossimilhança , Simulação por Computador
4.
Int J Gynecol Pathol ; 42(5): 523-528, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36811844

RESUMO

Mesonephric neoplasms of the lower female genital tract are rare. To date, there are scarce reports of benign biphasic vaginal mesonephric lesions, and none have included immunohistochemical and/or molecular analysis. A biphasic neoplasm of mesonephric-type was incidentally identified in the vaginal submucosal tissue of a 55-yr-old woman who underwent a right salpingo-oophorectomy for an ovarian cyst. The well-circumscribed, 5 mm nodule exhibited white-tan, firm homogenous cut surfaces. Microscopic examination showed a lobular arrangement of glands with columnar to the cuboidal epithelium and intraluminal eosinophilic secretions, embedded within a myofibromatous stroma. Cytologic atypia and mitotic activity were absent. Immunohistochemical staining for PAX8 and GATA3 demonstrated diffuse expression in the glandular epithelium, CD10 exhibited a patchy luminal expression pattern, while TTF1, ER, PR, p16, and NKX3.1 were negative. Desmin highlighted a subset of the stromal cells, but myogenin was negative. Whole exome sequencing demonstrated variants of unknown significance in multiple genes including PIK3R1 and NFIA . The morphologic and immunohistochemical profiles are consistent with a benign mesonephric neoplasm. This is the first report describing the immunohistochemical and whole exome sequencing results for a benign biphasic vaginal mesonephric neoplasm. To the best of our knowledge, benign mesonephric adenomyofibroma has not been previously reported in this anatomic location.


Assuntos
Neoplasias Epiteliais e Glandulares , Cistos Ovarianos , Feminino , Humanos , Epitélio , Salpingo-Ooforectomia
5.
Curr Oncol Rep ; 25(6): 549-558, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36943555

RESUMO

PURPOSE OF REVIEW: This review provides an overview of the available therapies for treating neuropathic and/or cardiac manifestations of transthyretin amyloidosis (ATTR), as well as investigational therapeutic agents in ongoing clinical trials. We discuss additional emergent approaches towards thwarting this life-threatening disease that until recently was considered virtually untreatable. RECENT FINDINGS: Advances in noninvasive diagnostic methods for detecting ATTR have facilitated easier diagnosis and detection at an earlier stage of disease when therapeutic interventions are likely to be more effective. There are now several ATTR-directed treatments that are clinically available, as well as investigational agents that are being studied in clinical trials. Therapeutic strategies include tetramer stabilization, gene silencing, and fibril disruption. ATTR has been historically underdiagnosed. With advances in diagnostic methods and the advent of disease-modifying treatments, early diagnosis and initiation of treatment is revolutionizing management of this disease.


Assuntos
Neuropatias Amiloides Familiares , Cardiomiopatias , Humanos , Neuropatias Amiloides Familiares/diagnóstico , Neuropatias Amiloides Familiares/genética , Neuropatias Amiloides Familiares/terapia
6.
Mov Disord ; 37(4): 826-841, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35218056

RESUMO

BACKGROUND: The Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) has become the gold standard for evaluating different domains in Parkinson's disease (PD), and it is commonly used in clinical practice, research, and clinical trials. OBJECTIVES: The objectives are to validate the Arabic-translated version of the MDS-UPDRS and to assess its factor structure compared with the English version. METHODS: The study was carried out in three phases: first, the English version of the MDS-UPDRS was translated into Arabic and subsequently back-translated into English by independent translation team; second, cognitive pretesting of selected items was performed; third, the Arabic version was tested in over 400 native Arabic-speaking PD patients. The psychometric properties of the translated version were analyzed using confirmatory factor analysis (CFA) as well as exploratory factor analysis (EFA). RESULTS: The factor structure of the Arabic version was consistent with that of the English version based on the high CFIs for all four parts of the MDS-UPDRS in the CFA (CFI ≥0.90), confirming its suitability for use in Arabic. CONCLUSIONS: The Arabic version of the MDS-UPDRS has good construct validity in Arabic-speaking patients with PD and has been thereby designated as an official MDS-UPDRS version. The data collection methodology among Arabic-speaking countries across two continents of Asia and Africa provides a roadmap for validating additional MDS rating scale initiatives and is strong evidence that underserved regions can be energically mobilized to promote efforts that apply to better clinical care, education, and research for PD. © 2022 International Parkinson and Movement Disorder Society.


Assuntos
Doença de Parkinson , Análise Fatorial , Humanos , Testes de Estado Mental e Demência , Doença de Parkinson/diagnóstico , Doença de Parkinson/psicologia , Índice de Gravidade de Doença , Sociedades Médicas
7.
Stat Med ; 41(15): 2894-2907, 2022 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-35347750

RESUMO

The joint model for longitudinal and survival data improves time-to-event predictions by including longitudinal outcome variables in addition to baseline covariates. However, in practice, joint models may be limited by parametric assumptions in both the longitudinal and survival submodels. In addition, computational difficulties arise when considering multiple longitudinal outcomes due to the large number of random effects to be integrated out in the full likelihood. In this article, we discuss several recent machine learning methods for incorporating multivariate longitudinal data for time-to-event prediction. The presented methods use functional data analysis or convolutional neural networks to model the longitudinal data, both of which scale well to multiple longitudinal outcomes. In addition, we propose a novel architecture based on the transformer neural network, named TransformerJM, which jointly models longitudinal and time-to-event data. The prognostic abilities of each model are assessed and compared through both simulation and real data analysis on Alzheimer's disease datasets. Specifically, the models were evaluated based on their ability to dynamically update predictions as new longitudinal data becomes available. We showed that TransformerJM improves upon the predictive performance of existing methods across different scenarios.


Assuntos
Doença de Alzheimer , Aprendizado Profundo , Humanos , Aprendizado de Máquina , Redes Neurais de Computação , Prognóstico
8.
Mov Disord ; 36(12): 2853-2861, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34327755

RESUMO

BACKGROUND: Predicting Parkinson's disease (PD) progression may enable better adaptive and targeted treatment planning. OBJECTIVE: Develop a prognostic model using multiple, easily acquired longitudinal measures to predict temporal clinical progression from Hoehn and Yahr (H&Y) stage 1 or 2 to stage 3 in early PD. METHODS: Predictive longitudinal measures of PD progression were identified by the joint modeling method. Measures were extracted by multivariate functional principal component analysis methods and used as covariates in Cox proportional hazards models. The optimal model was developed from the Parkinson's Progression Marker Initiative (PPMI) data set and confirmed with external validation from the Longitudinal and Biomarker Study in PD (LABS-PD) study. RESULTS: The proposed prognostic model with longitudinal information of selected clinical measures showed significant advantages in predicting PD temporal progression in comparison to a model with only baseline information (iAUC = 0.812 vs. 0.743). The modeling results allowed the development of a prognostic index for categorizing PD patients into low, mid, and high risk of progression to HY 3 that is offered to facilitate physician-patient discussion on prognosis. CONCLUSION: Incorporating longitudinal information of multiple clinical measures significantly enhances predictive performance of prognostic models. Furthermore, the proposed prognostic index enables clinicians to classify patients into different risk groups, which could be adaptively updated as new longitudinal information becomes available. Modeling of this type allows clinicians to utilize observational data sets that inform on disease natural history and specifically, for precision medicine, allows the insertion of a patient's clinical data to calculate prognostic estimates at the individual case level. © 2021 International Parkinson and Movement Disorder Society.


Assuntos
Doença de Parkinson , Biomarcadores , Progressão da Doença , Humanos , Estudos Longitudinais , Doença de Parkinson/diagnóstico , Prognóstico
9.
Eur Neurol ; 84(6): 444-449, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34261060

RESUMO

INTRODUCTION: The Unified Dyskinesia Rating Scale (UDysRS) was developed to provide a comprehensive rating tool of dyskinesia in Parkinson's disease (PD). Because dyskinesia therapy trials involve multicenter studies, having a scale that is validated in multiple non-English languages is pivotal to international efforts to treat dyskinesia. The aim of the present study was to organize and perform an independent validation of the UDysRS Finnish version. METHODS: The UDysRS was translated into Finnish and then back-translated into English using 2 independent teams. Cognitive pretesting was conducted on the Finnish version and required modifications to the structure or wording of the translation. The final Finnish version was administered to 250 PD patients whose native language is Finnish. The data were analyzed to assess the confirmatory factor structure to the Spanish UDysRS (the reference standard). Secondary analyses included an exploratory factor analysis (EFA), independent of the reference standard. RESULTS: The comparative fit index (CFI), in comparison with the reference standard factor structure, was 0.963 for Finnish. In the EFA, where variability from sample to sample is expected, isolated item differences of factor structure were found between the Finnish and Reference Standard versions of the UDysRS. These subtle differences may relate to differences in sample composition or variations in disease status. CONCLUSION: The overall factor structure of the Finnish version was consistent with that of the reference standard, and it can be designated as the official version of the UDysRS for Finnish speaking populations.


Assuntos
Discinesias , Idioma , Finlândia , Humanos , Índice de Gravidade de Doença , Traduções
10.
Neurol Neurochir Pol ; 55(2): 186-194, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33528833

RESUMO

BACKGROUND: In 2008, the Movement Disorders Society published the Unified Dyskinesia Rating Scale (UDysRS). This has become the established tool for assessing the severity and disability associated with dyskinesia in patients with Parkinson's Disease (PD). We translated and validated the Polish version of the UDysRS, explored its dimensionality, and compared it to the Spanish version, which is the Reference Standard for UDysRS translations. MATERIAL AND METHODS: The UDysRS was translated into Polish by a team led by JS and GO. The back-translation, completed by colleagues fluent in both Polish and English who were not involved in the original translation, was reviewed and approved by the Executive Committee of the MDS Rating Scales Programme. Then the translated version of the UDysRS underwent cognitive pretesting, and the translation was modified based on the results. The approved version was considered to be the Official Working Document of the Polish UDysRS and was tested on 250 Polish PD patients recruited at movement disorder centres. Data was compared to the Reference Standard used for validating UDysRS translations. RESULTS: The overall factor structure of the Polish version was consistent with that of the Reference Standard version, as evidenced by the high Confirmatory Fit Index score (CFI = 0.98). The Polish UDysRS was thus confirmed to share a common factor structure with the Reference Standard. CONCLUSIONS: The Official Polish UDysRS translation is recommended for use in clinical and research settings. Worldwide use of uniform rating measures offers a common ground to study similarities and differences in disease manifestations and progression across cultures.


Assuntos
Discinesias , Doença de Parkinson , Discinesias/diagnóstico , Humanos , Doença de Parkinson/diagnóstico , Polônia , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Traduções
11.
Lancet Oncol ; 21(8): 1099-1109, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32645282

RESUMO

BACKGROUND: Cabozantinib is a multikinase inhibitor of MET, VEGFR, AXL, and RET, which also has an effect on the tumour immune microenvironment by decreasing regulatory T cells and myeloid-derived suppressor cells. In this study, we examined the activity of cabozantinib in patients with metastatic platinum-refractory urothelial carcinoma. METHODS: This study was an open-label, single-arm, three-cohort phase 2 trial done at the National Cancer Institute (Bethesda, MD, USA). Eligible patients were 18 years or older, had histologically confirmed urothelial carcinoma or rare genitourinary tract histologies, Karnofsky performance scale index of 60% or higher, and documented disease progression after at least one previous line of platinum-based chemotherapy (platinum-refractory). Cohort one included patients with metastatic urothelial carcinoma with measurable disease as defined by Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. Two additional cohorts that enrolled in parallel (patients with bone-only urothelial carcinoma metastases and patients with rare histologies of the genitourinary tract) were exploratory. Patients received cabozantinib 60 mg orally once daily in 28-day cycles until disease progression or unacceptable toxicity. The primary endpoint was investigator-assessed objective response rate by RECIST in cohort one. Response was assessed in all patients who met the eligibility criteria and who received at least 8 weeks of therapy. All patients who received at least one dose of cabozantinib were included in the safety analysis. This completed study is registered with ClinicalTrials.gov, NCT01688999. FINDINGS: Between Sept 28, 2012, and Oct, 20, 2015, 68 patients were enrolled on the study (49 in cohort one, six in cohort two, and 13 in cohort three). All patients received at least one dose of cabozantinib. The median follow-up was 61·2 months (IQR 53·8-70·0) for the 57 patients evaluable for response. In the 42 evaluable patients in cohort one, there was one complete response and seven partial responses (objective response rate 19%, 95% CI 9-34). The most common grade 3-4 adverse events were fatigue (six [9%] patients), hypertension (five [7%]), proteinuria (four [6%]), and hypophosphataemia (four [6%]). There were no treatment-related deaths. INTERPRETATION: Cabozantinib has single-agent clinical activity in patients with heavily pretreated, platinum-refractory metastatic urothelial carcinoma with measurable disease and bone metastases and is generally well tolerated. Cabozantinib has innate and adaptive immunomodulatory properties providing a rationale for combining cabozantinib with immunotherapeutic strategies. FUNDING: National Cancer Institute Intramural Program and the Cancer Therapy Evaluation Program.


Assuntos
Anilidas/uso terapêutico , Antineoplásicos/uso terapêutico , Carcinoma de Células de Transição/tratamento farmacológico , Piridinas/uso terapêutico , Neoplasias Urológicas/tratamento farmacológico , Adulto , Idoso , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos de Platina/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico
12.
J Am Chem Soc ; 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33207870

RESUMO

The predictive synthesis of metal nanocrystals with desired structures relies on the precise control of the crystal formation process. Using a capping ligand is an effective method to affect the reduction of metal ions and the formation of nanocrystals. However, predictively synthesizing nanostructures has been difficult to achieve using conventional capping ligands. DNA, as a class of the promising biomolecular capping ligands, has been used to generate sequence-specific morphologies in various metal nanocrystals. However, mechanistic insight into the DNA-mediated nanocrystal formation remains elusive due to the lack of quantitative experimental evidence. Herein, we quantitatively analyzed the precise control of DNA over Ag+ reduction and the structures of resulting Au-Ag core-shell nanocrystals. We derived the equilibrium binding constants between DNA and Ag+, the kinetic rate constants of sequence-specific Ag+ reduction pathways, and the percentage of active surface sites remaining on the nanocrystals after DNA passivation. These three synergistic factors influence the nucleation and growth process both thermodynamically and kinetically, which contributed to the morphological evolution of Au-Ag nanocrystals synthesized with different DNA sequences. This study demonstrates the potential of using functional DNA sequences as a versatile and tunable capping ligand system for the predictable synthesis of metal nanostructures.

13.
Eur J Nucl Med Mol Imaging ; 47(1): 178-184, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31522271

RESUMO

PURPOSE: We evaluated the prognostic value of 18F-sodium fluoride (NaF) PET/CT in patients with urological malignancies treated with cabozantinib and nivolumab with or without ipilimumab. METHODS: We prospectively recruited patients with advanced urological malignancies into a phase I trial of cabozantinib plus nivolumab with or without ipilimumab. NaF PET/CT scans were performed pre- and 8 weeks post-treatment. We measured the total volume of fluoride avid bone (FTV) using a standardized uptake value (SUV) threshold of 10. We used Kaplan-Meier analysis to predict the overall survival (OS) of patients in terms of SUVmax, FTV, total lesion fluoride (TLF) uptake at baseline and 8 weeks post-treatment, and percent change in FTV and TLF. RESULT: Of 111 patients who underwent NaF PET/CT, 30 had bone metastases at baseline. Four of the 30 patients survived for the duration of the study period. OS ranged from 0.23 to 34 months (m) (median 6.0 m). The baseline FTV of all 30 patients ranged from 9.6 to 1570 ml (median 439 ml). The FTV 8 weeks post-treatment was 56-6296 ml (median 448 ml) from 19 available patients. Patients with higher TLF at baseline had shorter OS than patients with lower TLF (3.4 vs 14 m; p = 0.022). Patients with higher SUVmax at follow-up had shorter OS than patients with lower SUVmax (5.6 vs 24 m; p = 0.010). However, FTV and TLF 8 weeks post-treatment did not show a significant difference between groups (5.6 vs 17 m; p = 0.49), and the percent changes in FTV (12 vs 14 m; p = 0.49) and TLF (5.6 vs 17 m; p = 0.54) also were not significant. CONCLUSION: Higher TLF at baseline and higher SUVmax at follow-up NaF PET/CT corresponded with shorter survival in patients with bone metastases from urological malignancies who underwent treatment. NaF PET/CT may be a useful predictor of OS in this population.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias Urogenitais , Anilidas , Fluoretos , Humanos , Ipilimumab , Nivolumabe/uso terapêutico , Piridinas , Fluoreto de Sódio
14.
Echocardiography ; 37(3): 404-411, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32077529

RESUMO

AIMS: To investigate the relationship between fitness, heart failure (HF) risk factors (age, blood pressure, and obesity), and global/regional myocardial longitudinal strain in young adults undergoing stress testing. METHODS: Individuals 25-55 years old without any significant medical history, not taking medications, and with a normal maximal stress echocardiogram were eligible. Global and regional longitudinal strain (LS) was evaluated by 2D speckle tracking echocardiography. RESULTS: One hundred and seventy patients were included, of which 60% were males. The mean age was 43 years old, 49% had optimal blood pressure, and 30% were obese. On average, patients achieved 10.5 (3) METS, and the global LS was -19.9 (3.1) %. Reduced fitness was associated with decreased global longitudinal strain (GLS). Those in the top GLS quartile walked on average 1 minute and 21 seconds longer compared with the lowest quartile (P < .001). The effect of fitness on LS was preferential to the mid and apex, such that there was an apex-to-base gradient. Obesity was also independently associated with reduced GLS. However, the reduction in LS in obese individuals was more prominent at the base and mid-walls with relative sparing of the apex. Similar to fitness, aging was also associated with an increase in the apex-to-base gradient of LS. Furthermore, diastolic filling parameters correlated distinctively with regional LS. CONCLUSIONS: In young adults without cardiovascular disease, low fitness and obesity are independently associated with reduced left ventricular longitudinal strain. There is a differential effect of HF risk factors on regional longitudinal function.


Assuntos
Ecocardiografia , Insuficiência Cardíaca , Adulto , Diástole , Feminino , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Função Ventricular Esquerda , Adulto Jovem
15.
Mol Biol Evol ; 35(10): 2390-2400, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29955873

RESUMO

Viral evolutionary pathways are determined by the fitness landscape, which maps viral genotype to fitness. However, a quantitative description of the landscape and the evolutionary forces on it remain elusive. Here, we apply a biophysical fitness model based on capsid folding stability and antibody binding affinity to predict the evolutionary pathway of norovirus escaping a neutralizing antibody. The model is validated by experimental evolution in bulk culture and in a drop-based microfluidics that propagates millions of independent small viral subpopulations. We demonstrate that along the axis of binding affinity, selection for escape variants and drift due to random mutations have the same direction, an atypical case in evolution. However, along folding stability, selection and drift are opposing forces whose balance is tuned by viral population size. Our results demonstrate that predictable epistatic tradeoffs between molecular traits of viral proteins shape viral evolution.


Assuntos
Afinidade de Anticorpos , Evolução Biológica , Aptidão Genética , Modelos Genéticos , Norovirus/genética , Animais , Anticorpos Neutralizantes , Proteínas do Capsídeo/fisiologia , Epistasia Genética , Camundongos , Dobramento de Proteína , Estabilidade Proteica , Seleção Genética
16.
J Cardiovasc Electrophysiol ; 28(2): 185-191, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27885751

RESUMO

BACKGROUND: Prolonged PR intervals may impair atrioventricular mechanical coupling and adversely affect cardiac performance. We hypothesize that patients with advanced systolic heart failure, wide QRS complexes, and prolonged PR intervals will have improved survival from CRT-D regardless of whether left bundle branch block (LBBB) or non-LBBB is present. METHODS AND RESULTS: A total of 308 patients enrolled in the optimal pharmacologic therapy (OPT) and 595 patients in the cardiac resynchronization therapy with defibrillation (CRT-D) arms of the Comparison of Medical Therapy, Pacing, and Defibrillation in Heart Failure trial were stratified according to normal (≤230 ms) or prolonged PR interval (>230 ms). The incidence of all-cause mortality (ACM) or hospitalization (primary endpoint) and ACM (secondary endpoint) was compared using Kaplan-Meier curves. Cox proportional hazards models for the primary and secondary endpoints were fit with LBBB status and baseline PR interval. CRT-D treatment reduced both hospitalization/ACM (P = 0.002) and ACM (P = 0.003) compared to OPT. However, CRT-D was increasingly more effective in reducing ACM hazard in patients with longer baseline PR intervals (P = 0.002) regardless of LBBB status. In particular, in the prolonged baseline PR interval subgroup, ACM was reduced with CRT-D compared to OPT (P = 0.001) with little evidence of ACM reduction in the normal PR subgroup (P = 0.07). CONCLUSIONS: In patients with advanced systolic heart failure, wide QRS complexes, and prolonged PR intervals, restoration of atrioventricular mechanical coupling with CRT-D may improve survival regardless of LBBB status. In patients with non-LBBB, a benefit from CRT-D may occur with prolonged PR intervals.


Assuntos
Bloqueio de Ramo/terapia , Terapia de Ressincronização Cardíaca , Cardioversão Elétrica , Insuficiência Cardíaca Sistólica/terapia , Frequência Cardíaca , Potenciais de Ação , Idoso , Antiarrítmicos/uso terapêutico , Bloqueio de Ramo/diagnóstico , Bloqueio de Ramo/mortalidade , Bloqueio de Ramo/fisiopatologia , Terapia de Ressincronização Cardíaca/efeitos adversos , Terapia de Ressincronização Cardíaca/mortalidade , Dispositivos de Terapia de Ressincronização Cardíaca , Desfibriladores Implantáveis , Cardioversão Elétrica/efeitos adversos , Cardioversão Elétrica/instrumentação , Cardioversão Elétrica/mortalidade , Feminino , Insuficiência Cardíaca Sistólica/diagnóstico , Insuficiência Cardíaca Sistólica/mortalidade , Insuficiência Cardíaca Sistólica/fisiopatologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Análise Multivariada , Modelos de Riscos Proporcionais , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
17.
J Immunol ; 194(2): 560-74, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25488990

RESUMO

Interactions of B7H1 (programmed death ligand 1 [PD-L1]) with its two ligands, PD-1 and CD80, on T cells play a pivotal role in controlling T cell activation, proliferation, anergy, and apoptosis. However, the interactions between the two pathways remain unknown. Using an alloimmune response model of graft-versus-host disease (GVHD), we report in this study that: 1) Comparison of proliferation and apoptosis of wild-type (WT) and PD-1(-/-)CD4(+) conventional T (Tcon) cells in WT and B7H1(-/-) recipients revealed that B7H1/CD80 interaction per se augments T cell proliferation, and this interaction augments T cell apoptosis mediated by B7H1/PD-1 interaction. This observation was recapitulated in an in vitro MLR assay. 2) Specific blockade of the B7H1/CD80 axis by anti-B7H1 mAb reduces WT-alloreactive Tcon cell proliferation, IL-2 production, expression of PD-1, and apoptosis, resulting in worsening GVHD. In contrast, specific blockade of B7H1/CD80 interaction reduces donor PD-1(-/-) Tcon cell proliferation without an impact on apoptosis, resulting in ameliorating GVHD. 3) B7H1 fused to an Ig Fc domain (B7H1-Ig), when produced in vivo by hydrodynamic injection of B7H1-Ig plasmid, ameliorates GVHD by augmenting proliferation and apoptosis of WT- alloreactive Tcon cells. Conversely, B7H1-Ig treatment has no impact on apoptosis but augments PD-1(-/-) T cell proliferation and worsens GVHD. These results indicate that B7H1/CD80 interaction augments Tcon cell proliferation, IL-2 production, and expression of PD-1, which leads to increased apoptosis mediated by the B7H1/PD-1 pathway. Additionally, by engaging both PD-1 and CD80, B7H1-Ig can be a powerful therapeutic reagent for downregulating the T cell immune response.


Assuntos
Apoptose/imunologia , Antígeno B7-1/imunologia , Antígeno B7-H1/imunologia , Linfócitos T CD4-Positivos/imunologia , Doença Enxerto-Hospedeiro/imunologia , Receptor de Morte Celular Programada 1/imunologia , Animais , Apoptose/genética , Antígeno B7-1/genética , Antígeno B7-H1/genética , Antígeno B7-H1/farmacologia , Linfócitos T CD4-Positivos/patologia , Proliferação de Células/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/imunologia , Doença Enxerto-Hospedeiro/genética , Doença Enxerto-Hospedeiro/patologia , Doença Enxerto-Hospedeiro/terapia , Interleucina-2/genética , Interleucina-2/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Receptor de Morte Celular Programada 1/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/farmacologia
18.
J Virol ; 89(15): 7722-34, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25972549

RESUMO

UNLABELLED: Human noroviruses (HuNoVs) are positive-sense RNA viruses that can cause severe, highly infectious gastroenteritis. HuNoV outbreaks are frequently associated with recombination between circulating strains. Strain genotyping and phylogenetic analyses show that noroviruses often recombine in a highly conserved region near the junction of the viral polyprotein (open reading frame 1 [ORF1]) and capsid (ORF2) genes and occasionally within the RNA-dependent RNA polymerase (RdRP) gene. Although genotyping methods are useful for tracking changes in circulating viral populations, they report only the dominant recombinant strains and do not elucidate the frequency or range of recombination events. Furthermore, the relatively low frequency of recombination in RNA viruses has limited studies to cell culture or in vitro systems, which do not reflect the complexities and selective pressures present in an infected organism. Using two murine norovirus (MNV) strains to model coinfection, we developed a microfluidic platform to amplify, detect, and recover individual recombinants following in vitro and in vivo coinfection. One-step reverse transcriptase PCR (RT-PCR) was performed in picoliter drops with primers that identified the wild-type and recombinant progenies and scanned for recombination breakpoints at ∼1-kb intervals. We detected recombination between MNV strains at multiple loci spanning the viral protease, RdRP, and capsid ORFs and isolated individual recombinant RNA genomes that were present at a frequency of 1/300,000 or higher. This study is the first to examine norovirus recombination following coinfection of an animal and suggests that the exchange of RNA among viral genomes in an infected host occurs in multiple locations and is an important driver of genetic diversity. IMPORTANCE: RNA viruses increase diversity and escape host immune barriers by genomic recombination. Studies using a number of viral systems indicate that recombination occurs via template switching by the virus-encoded RNA-dependent RNA polymerase (RdRP). However, factors that govern the frequency and positions of recombination in an infected organism remain largely unknown. This work leverages advances in the applied physics of drop-based microfluidics to isolate and sequence rare recombinants arising from the coinfection of mice with two distinct strains of murine norovirus. This study is the first to detect and analyze norovirus recombination in an animal model.


Assuntos
Infecções por Caliciviridae/virologia , Norovirus/genética , Norovirus/isolamento & purificação , Recombinação Genética , Animais , Variação Genética , Genótipo , Humanos , Camundongos , Microfluídica , Dados de Sequência Molecular , Norovirus/classificação , Filogenia
19.
Sex Abuse ; 28(3): 253-67, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25143435

RESUMO

A prevailing cultural stereotype about sex offenders is that they tend to specialize in sexual offending. Many recent policy developments-mainly aimed to restrict the liberties of sex offenders-are rooted in this idea. We examined the correctional and arrest records of a sample of 312 sex offenders released on parole in Colorado to determine the prevalence of sexual specialization among these offenders, and to compare the legal and social characteristics of specialists and versatile sex offenders. Overall we found that very few participants officially classified as sex offenders fit the specialist stereotype. Study participants generally displayed versatile histories of criminal offending. We also found that specialists were distinguishable from versatile offenders on certain indices of social integration and mental health, and they were more likely to have had a history of offending against children.


Assuntos
Criminosos/psicologia , Delitos Sexuais/psicologia , Comportamento Sexual/psicologia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Prisões , Recidiva , Delitos Sexuais/prevenção & controle
20.
J Cell Sci ; 126(Pt 17): 3948-60, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23813962

RESUMO

Corneal scarring due to injury is a leading cause of blindness worldwide and results from dysregulated inflammation and angiogenesis during wound healing. Here we demonstrate that the extracellular matrix metalloproteinase MMP12 (macrophage metalloelastase) is an important regulator of these repair processes. Chemical injury resulted in higher expression of the fibrotic markers α-smooth muscle actin and type I collagen, and increased levels of angiogenesis in corneas of Mmp12(-/-) mice compared with corneas of wild-type mice. In vivo, we observed altered immune cell dynamics in Mmp12(-/-) corneas by confocal imaging. We determined that the altered dynamics were the result of an altered inflammatory response, with delayed neutrophil infiltration during the first day and excessive macrophage infiltration 6 days later, mediated by altered expression levels of chemokines CXCL1 and CCL2, respectively. Corneal repair returned to normal upon inhibition of these chemokines. Taken together, these data show that MMP12 has a protective effect on corneal fibrosis during wound repair through regulation of immune cell infiltration and angiogenesis.


Assuntos
Lesões da Córnea , Fibrose/prevenção & controle , Inflamação/imunologia , Metaloproteinase 12 da Matriz/metabolismo , Cicatrização/fisiologia , Actinas/biossíntese , Animais , Transplante de Medula Óssea , Quimiocina CCL2/antagonistas & inibidores , Quimiocina CCL2/biossíntese , Quimiocina CCL2/metabolismo , Quimiocina CXCL1/antagonistas & inibidores , Quimiocina CXCL1/biossíntese , Quimiocina CXCL1/metabolismo , Colágeno Tipo I/biossíntese , Córnea/imunologia , Córnea/metabolismo , Feminino , Fibrose/metabolismo , Macrófagos/imunologia , Masculino , Metaloproteinase 12 da Matriz/genética , Camundongos , Camundongos Knockout , Neovascularização Fisiológica/genética , Infiltração de Neutrófilos/imunologia
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