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1.
Radiol Imaging Cancer ; 6(1): e230033, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38180338

RESUMO

Purpose To describe the design, conduct, and results of the Breast Multiparametric MRI for prediction of neoadjuvant chemotherapy Response (BMMR2) challenge. Materials and Methods The BMMR2 computational challenge opened on May 28, 2021, and closed on December 21, 2021. The goal of the challenge was to identify image-based markers derived from multiparametric breast MRI, including diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) MRI, along with clinical data for predicting pathologic complete response (pCR) following neoadjuvant treatment. Data included 573 breast MRI studies from 191 women (mean age [±SD], 48.9 years ± 10.56) in the I-SPY 2/American College of Radiology Imaging Network (ACRIN) 6698 trial (ClinicalTrials.gov: NCT01042379). The challenge cohort was split into training (60%) and test (40%) sets, with teams blinded to test set pCR outcomes. Prediction performance was evaluated by area under the receiver operating characteristic curve (AUC) and compared with the benchmark established from the ACRIN 6698 primary analysis. Results Eight teams submitted final predictions. Entries from three teams had point estimators of AUC that were higher than the benchmark performance (AUC, 0.782 [95% CI: 0.670, 0.893], with AUCs of 0.803 [95% CI: 0.702, 0.904], 0.838 [95% CI: 0.748, 0.928], and 0.840 [95% CI: 0.748, 0.932]). A variety of approaches were used, ranging from extraction of individual features to deep learning and artificial intelligence methods, incorporating DCE and DWI alone or in combination. Conclusion The BMMR2 challenge identified several models with high predictive performance, which may further expand the value of multiparametric breast MRI as an early marker of treatment response. Clinical trial registration no. NCT01042379 Keywords: MRI, Breast, Tumor Response Supplemental material is available for this article. © RSNA, 2024.


Assuntos
Neoplasias da Mama , Imageamento por Ressonância Magnética Multiparamétrica , Feminino , Humanos , Pessoa de Meia-Idade , Inteligência Artificial , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Imageamento por Ressonância Magnética , Terapia Neoadjuvante , Resposta Patológica Completa , Adulto
2.
IEEE Trans Med Imaging ; 43(1): 377-391, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37603482

RESUMO

Our lab at the University of Pennsylvania (UPenn) is investigating novel designs for digital breast tomosynthesis. We built a next-generation tomosynthesis system with a non-isocentric geometry (superior-to-inferior detector motion). This paper examines four metrics of image quality affected by this design. First, aliasing was analyzed in reconstructions prepared with smaller pixelation than the detector. Aliasing was assessed with a theoretical model of r -factor, a metric calculating amplitudes of alias signal relative to input signal in the Fourier transform of the reconstruction of a sinusoidal object. Aliasing was also assessed experimentally with a bar pattern (illustrating spatial variations in aliasing) and 360°-star pattern (illustrating directional anisotropies in aliasing). Second, the point spread function (PSF) was modeled in the direction perpendicular to the detector to assess out-of-plane blurring. Third, power spectra were analyzed in an anthropomorphic phantom developed by UPenn and manufactured by Computerized Imaging Reference Systems (CIRS), Inc. (Norfolk, VA). Finally, calcifications were analyzed in the CIRS Model 020 BR3D Breast Imaging Phantom in terms of signal-to-noise ratio (SNR); i.e., mean calcification signal relative to background-tissue noise. Image quality was generally superior in the non-isocentric geometry: Aliasing artifacts were suppressed in both theoretical and experimental reconstructions prepared with smaller pixelation than the detector. PSF width was also reduced at most positions. Anatomic noise was reduced. Finally, SNR in calcification detection was improved. (A potential trade-off of smaller-pixel reconstructions was reduced SNR; however, SNR was still improved by the detector-motion acquisition.) In conclusion, the non-isocentric geometry improved image quality in several ways.


Assuntos
Calcinose , Processamento de Imagem Assistida por Computador , Humanos , Processamento de Imagem Assistida por Computador/métodos , Mama/diagnóstico por imagem , Mamografia/métodos , Simulação por Computador , Modelos Teóricos , Imagens de Fantasmas , Algoritmos
3.
Brain ; 147(2): 717-734, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-37931057

RESUMO

Despite effective antiretroviral therapies, 20-30% of persons with treated HIV infection develop a neurodegenerative syndrome termed HIV-associated neurocognitive disorder (HAND). HAND is driven by HIV expression coupled with inflammation in the brain but the mechanisms underlying neuronal damage and death are uncertain. The inflammasome-pyroptosis axis coordinates an inflammatory type of regulated lytic cell death that is underpinned by the caspase-activated pore-forming gasdermin proteins. The mechanisms driving neuronal pyroptosis were investigated herein in models of HAND, using multi-platform molecular and morphological approaches that included brain tissues from persons with HAND and simian immunodeficiency virus (SIV)-infected non-human primates as well as cultured human neurons. Neurons in the frontal cortices from persons with HAND showed increased cleaved gasdermin E (GSDME), which was associated with ß-III tubulin degradation and increased HIV levels. Exposure of cultured human neurons to the HIV-encoded viral protein R (Vpr) elicited time-dependent cleavage of GSDME and Ninjurin-1 (NINJ1) induction with associated cell lysis that was inhibited by siRNA suppression of both proteins. Upstream of GSDME cleavage, Vpr exposure resulted in activation of caspases-1 and 3. Pretreatment of Vpr-exposed neurons with the caspase-1 inhibitor, VX-765, reduced cleavage of both caspase-3 and GSDME, resulting in diminished cell death. To validate these findings, we examined frontal cortical tissues from SIV-infected macaques, disclosing increased expression of GSDME and NINJ1 in cortical neurons, which was co-localized with caspase-3 detection in animals with neurological disease. Thus, HIV infection of the brain triggers the convergent activation of caspases-1 and -3, which results in GSDME-mediated neuronal pyroptosis in persons with HAND. These findings demonstrate a novel mechanism by which a viral infection causes pyroptotic death in neurons while also offering new diagnostic and therapeutic strategies for HAND and other neurodegenerative disorders.


Assuntos
Infecções por HIV , Piroptose , Animais , Humanos , Caspases/metabolismo , Caspases/farmacologia , Caspase 3/metabolismo , Caspase 3/farmacologia , Gasderminas , HIV/metabolismo , Infecções por HIV/complicações , Neurônios/metabolismo , Transtornos Neurocognitivos/etiologia , Fatores de Crescimento Neural/metabolismo , Moléculas de Adesão Celular Neuronais/metabolismo
4.
Viruses ; 15(12)2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38140626

RESUMO

There is currently no cure for HIV infection although adherence to effective antiretroviral therapy (ART) suppresses replication of the virus in blood, increases CD4+ T-cell counts, reverses immunodeficiency, and increases life expectancy. Despite these substantial advances, ART is a lifelong treatment for people with HIV (PWH) and upon cessation or interruption, the virus quickly rebounds in plasma and anatomic sites, including the central nervous system (CNS), resulting in disease progression. With recent advances in quantifying viral burden, detection of genetically intact viral genomes, and isolation of replication-competent virus from brain tissues of PWH receiving ART, it has become apparent that the CNS viral reservoir (largely comprised of macrophage type cells) poses a substantial challenge for HIV cure strategies. Other obstacles impacting the curing of HIV include ageing populations, substance use, comorbidities, limited antiretroviral drug efficacy in CNS cells, and ART-associated neurotoxicity. Herein, we review recent findings, including studies of the proviral integration sites, reservoir decay rates, and new treatment/prevention strategies in the context of the CNS, together with highlighting the next steps for investigations of the CNS as a viral reservoir.


Assuntos
Infecções por HIV , Humanos , Infecções por HIV/tratamento farmacológico , Sistema Nervoso Central , Antirretrovirais/uso terapêutico , Antirretrovirais/farmacologia , Macrófagos , Replicação Viral , Carga Viral , Linfócitos T CD4-Positivos
5.
mBio ; 14(5): e0195023, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37773002

RESUMO

IMPORTANCE: In order to efficiently produce infectious viral particles, HIV must counter several restrictions exerted by host cell antiviral proteins. MARCH1 is a member of the MARCH protein family that restricts HIV infection by limiting the incorporation of viral envelope glycoproteins into nascent virions. Here, we identified two regulatory RNAs, microRNAs-25 and -93, induced by the HIV-1 accessory protein Vpu, that downregulate MARCH1 mRNA. We also show that Vpu induces these cellular microRNAs in macrophages by hijacking the cellular ß-catenin pathway. The notion that HIV-1 has evolved a mechanism to counteract MARCH1 restriction on viral infectivity underlines the importance of MARCH1 in the host antiviral response.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , MicroRNAs , Humanos , Infecções por HIV/metabolismo , HIV-1/fisiologia , Proteínas Virais Reguladoras e Acessórias/genética , Proteínas Virais Reguladoras e Acessórias/metabolismo , Proteínas do Vírus da Imunodeficiência Humana/genética , Antivirais/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Macrófagos/metabolismo , Proteínas Ligadas por GPI/metabolismo
6.
Curr HIV Res ; 21(4): 264-267, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37670698

RESUMO

BACKGROUND: Finding a cure for HIV is challenged by persisting reservoirs, the mapping of which necessitates invasive procedures. Inviting people with HIV (PWHIV) at the end of life to donate body specimens post-mortem through research autopsies is a novel approach, raising ethical concerns. OBJECTIVE: This case study aims to explore the motivations, barriers, and facilitators of a terminally-ill Canadian PWHIV who requested medical assistance in dying (MAID) and expressed interest in donating his body for HIV cure research. CASE PRESENTATION: An in-depth 3-hour and semi-structured interview was conducted with the participant. The interview transcription was thematically coded to identify motivations and perceived barriers and facilitators to participate in end-of-life HIV cure research. Our analysis identified six themes. Two themes expressed motivations: Collaboration in progress in health and science, seeing cure research as collaboration with professionals; and Opportunity to learn more, mostly about science and health. One theme expressed a barrier: Losing interest in or identification with long-term care research matters, especially those related to the management of long-term care. Three themes expressed by facilitators: Receiving information from professionals one trusts and knows, especially clinical and research teams; Perceiving research procedures as simple, useful, and embedded in care, perceiving clinical, educational, and interpersonal benefits that surpass costs of participation; and Perceiving research as one last way to contribute, that is, feeling useful or give back. CONCLUSION: Several circumstances facilitated the patient's participation: being a single man, having time to participate, having no strong religious belief, and valuing clear, direct communication. His motivations to participate in HIV cure research were altruistic, and also an experience of working with clinical and research teams. Finally, this perspective highlights HIV cure research participant candidates' need for education about research procedures.


Assuntos
Infecções por HIV , Masculino , Humanos , Infecções por HIV/tratamento farmacológico , HIV , Canadá , Autopsia
7.
Cell Rep ; 42(9): 113053, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37676762

RESUMO

HIV persists in tissues during antiretroviral therapy (ART), but the relative contribution of different anatomical compartments to the viral reservoir in humans remains unknown. We performed an extensive characterization of HIV reservoirs in two men who donated their bodies to HIV cure research and who had been on suppressive ART for years. HIV DNA is detected in all tissues, with large variations across anatomical compartments and between participants. Intact HIV genomes represent 2% and 25% of all proviruses in the two participants and are mainly detected in secondary lymphoid organs, with the spleen and mediastinal lymph nodes harboring intact viral genomes in both individuals. Multiple copies of identical HIV genomes are found in all tissues, indicating that clonal expansions are common in anatomical sites. The majority (>85%) of these expanded clones are shared across multiple tissues. These findings suggest that infected cells expand, migrate, and possibly circulate between anatomical sites.


Assuntos
Antirretrovirais , Infecções por HIV , Masculino , Humanos , Antirretrovirais/uso terapêutico , Provírus/genética , Células Clonais , Linfonodos , Linfócitos T CD4-Positivos , Carga Viral/genética
8.
Commun Med (Lond) ; 3(1): 46, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36997615

RESUMO

BACKGROUND: Early changes in breast intratumor heterogeneity during neoadjuvant chemotherapy may reflect the tumor's ability to adapt and evade treatment. We investigated the combination of precision medicine predictors of genomic and MRI data towards improved prediction of recurrence free survival (RFS). METHODS: A total of 100 women from the ACRIN 6657/I-SPY 1 trial were retrospectively analyzed. We estimated MammaPrint, PAM50 ROR-S, and p53 mutation scores from publicly available gene expression data and generated four, voxel-wise 3-D radiomic kinetic maps from DCE-MR images at both pre- and early-treatment time points. Within the primary lesion from each kinetic map, features of change in radiomic heterogeneity were summarized into 6 principal components. RESULTS: We identify two imaging phenotypes of change in intratumor heterogeneity (p < 0.01) demonstrating significant Kaplan-Meier curve separation (p < 0.001). Adding phenotypes to established prognostic factors, functional tumor volume (FTV), MammaPrint, PAM50, and p53 scores in a Cox regression model improves the concordance statistic for predicting RFS from 0.73 to 0.79 (p = 0.002). CONCLUSIONS: These results demonstrate an important step in combining personalized molecular signatures and longitudinal imaging data towards improved prognosis.


Early changes in tumor properties during treatment may tell us whether or not a patient's tumor is responding to treatment. Such changes may be seen on imaging. Here, changes in breast cancer properties are identified on imaging and are used in combination with gene markers to investigate whether response to treatment can be predicted using mathematical models. We demonstrate that tumor properties seen on imaging early on in treatment can help to predict patient outcomes. Our approach may allow clinicians to better inform patients about their prognosis and choose appropriate and effective therapies.

9.
Breast Cancer Res Treat ; 198(3): 535-544, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36800118

RESUMO

PURPOSE: Mammographic density (MD) is a strong breast cancer risk factor. MD may change over time, with potential implications for breast cancer risk. Few studies have assessed associations between MD change and breast cancer in racially diverse populations. We investigated the relationships between MD and MD change over time and breast cancer risk in a large, diverse screening cohort. MATERIALS AND METHODS: We retrospectively analyzed data from 8462 women who underwent ≥ 2 screening mammograms from Sept. 2010 to Jan. 2015 (N = 20,766 exams); 185 breast cancers were diagnosed 1-7 years after screening. Breast percent density (PD) and dense area (DA) were estimated from raw digital mammograms (Hologic Inc.) using LIBRA (v1.0.4). For each MD measure, we modeled breast density change between two sequential visits as a function of demographic and risk covariates. We used Cox regression to examine whether varying degrees of breast density change were associated with breast cancer risk, accounting for multiple exams per woman. RESULTS: PD at any screen was significantly associated with breast cancer risk (hazard ratio (HR) for PD = 1.03 (95% CI [1.01, 1.05], p < 0.0005), but neither change in breast density nor more extreme than expected changes in breast density were associated with breast cancer risk. We found no evidence of differences in density change or breast cancer risk due to density change by race. Results using DA were essentially identical. CONCLUSIONS: Using a large racially diverse cohort, we found no evidence of association between short-term change in MD and risk of breast cancer, suggesting that short-term MD change is not a strong predictor for risk.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/epidemiologia , Densidade da Mama , Estudos Retrospectivos , Detecção Precoce de Câncer , Mamografia/métodos , Fatores de Risco
10.
Viruses ; 15(2)2023 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-36851531

RESUMO

HIV-encoded DNA, RNA and proteins persist in the brain despite effective antiretroviral therapy (ART), with undetectable plasma and cerebrospinal fluid viral RNA levels, often in association with neurocognitive impairments. Although the determinants of HIV persistence have garnered attention, the expression and regulation of antiretroviral host restriction factors (RFs) in the brain for HIV and SIV remain unknown. We investigated the transcriptomic profile of antiretroviral RF genes by RNA-sequencing with confirmation by qRT-PCR in the cerebral cortex of people who are uninfected (HIV[-]), those who are HIV-infected without pre-mortem brain disease (HIV[+]), those who are HIV-infected with neurocognitive disorders (HIV[+]/HAND) and those with neurocognitive disorders with encephalitis (HIV[+]/HIVE). We observed significant increases in RF expression in the brains of HIV[+]/HIVE in association with the brain viral load. Machine learning techniques identified MAN1B1 as a key gene that distinguished the HIV[+] group from the HIV[+] groups with HAND. Analyses of SIV-associated RFs in brains from SIV-infected Chinese rhesus macaques with different ART regimens revealed diminished RF expression among ART-exposed SIV-infected animals, although ART interruption resulted in an induced expression of several RF genes including OAS3, RNASEL, MX2 and MAN1B1. Thus, the brain displays a distinct expression profile of RFs that is associated with the neurological status as well as the brain viral burden. Moreover, ART interruption can influence the brain's RF profile, which might contribute to disease outcomes.


Assuntos
Encefalopatias , Encefalite , Animais , Antirretrovirais , Encéfalo , Macaca mulatta , Transtornos Neurocognitivos , Infecções por HIV/virologia
11.
Viruses ; 15(2)2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36851576

RESUMO

Proprotein convertases activate various envelope glycoproteins and participate in cellular entry of many viruses. We recently showed that the convertase furin is critical for the infectivity of SARS-CoV-2, which requires cleavage of its spike protein (S) at two sites: S1/S2 and S2'. This study investigates the implication of the two cholesterol-regulating convertases SKI-1 and PCSK9 in SARS-CoV-2 entry. The assays used were cell-to-cell fusion in HeLa cells and pseudoparticle entry into Calu-3 cells. SKI-1 increased cell-to-cell fusion by enhancing the activation of SREBP-2, whereas PCSK9 reduced cell-to-cell fusion by promoting the cellular degradation of ACE2. SKI-1 activity led to enhanced S2' formation, which was attributed to increased metalloprotease activity as a response to enhanced cholesterol levels via activated SREBP-2. However, high metalloprotease activity resulted in the shedding of S2' into a new C-terminal fragment (S2″), leading to reduced cell-to-cell fusion. Indeed, S-mutants that increase S2″ formation abolished S2' and cell-to-cell fusion, as well as pseudoparticle entry, indicating that the formation of S2″ prevents SARS-CoV-2 cell-to-cell fusion and entry. We next demonstrated that PCSK9 enhanced the cellular degradation of ACE2, thereby reducing cell-to-cell fusion. However, different from the LDLR, a canonical target of PCSK9, the C-terminal CHRD domain of PCSK9 is dispensable for the PCSK9-induced degradation of ACE2. Molecular modeling suggested the binding of ACE2 to the Pro/Catalytic domains of mature PCSK9. Thus, both cholesterol-regulating convertases SKI-1 and PCSK9 can modulate SARS-CoV-2 entry via two independent mechanisms.


Assuntos
COVID-19 , Pró-Proteína Convertase 9 , Humanos , Enzima de Conversão de Angiotensina 2 , Fusão Celular , Células HeLa , Metaloproteases , Pró-Proteína Convertase 9/genética , SARS-CoV-2 , Proteína de Ligação a Elemento Regulador de Esterol 1
12.
Stem Cell Reports ; 18(2): 597-612, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36736326

RESUMO

Humanization of mice with functional T cells currently relies on co-implantation of hematopoietic stem cells from fetal liver and autologous fetal thymic tissue (so-called BLT mouse model). Here, we show that NOD/SCID/IL2rγnull mice humanized with cord blood- derived CD34+ cells and implanted with allogeneic pediatric thymic tissues excised during cardiac surgeries (CCST) represent an alternative to BLT mice. CCST mice displayed a strong immune reconstitution, with functional T cells originating from CD34+ progenitor cells. They were equally susceptible to mucosal or intraperitoneal HIV infection and had significantly higher HIV-specific T cell responses. Antiretroviral therapy (ART) robustly suppressed viremia and reduced the frequencies of cells carrying integrated HIV DNA. As in BLT mice, we observed a complete viral rebound following ART interruption, suggesting the presence of HIV reservoirs. In conclusion, CCST mice represent a practical alternative to BLT mice, broadening the use of humanized mice for research.


Assuntos
Infecções por HIV , Humanos , Camundongos , Animais , Criança , Camundongos SCID , Camundongos Endogâmicos NOD , Linfócitos T , Timo , Modelos Animais de Doenças , Camundongos Knockout
13.
Sci Rep ; 13(1): 2040, 2023 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-36739358

RESUMO

High-throughput extraction of radiomic features from low-dose CT scans can characterize the heterogeneity of the lung parenchyma and potentially aid in identifying subpopulations that may have higher risk of lung diseases, such as COPD, and lung cancer due to inflammation or obstruction of the airways. We aim to determine the feasibility of a lung radiomics phenotyping approach in a lung cancer screening cohort, while quantifying the effect of different CT reconstruction algorithms on phenotype robustness. We identified low-dose CT scans (n = 308) acquired with Siemens Healthineers scanners from patients who completed low-dose CT within our lung cancer screening program between 2015 and 2018 and had two different sets of image reconstructions kernel available (i.e., medium (I30f.), sharp (I50f.)) for the same acquisition. Following segmentation of the lung field, a total of 26 radiomic features were extracted from the entire 3D lung-field using a previously validated fully-automated lattice-based software pipeline, adapted for low-dose CT scans. The lattice in-house software was used to extract features including gray-level histogram, co-occurrence, and run-length descriptors. The lattice approach uses non-overlapping windows for traversing along pixels of images and calculates different features. Each feature was averaged for each scan within a range of lattice window sizes (W) of 4, 8 and 20 mm. The extracted imaging features from both datasets were harmonized to correct for differences in image acquisition parameters. Subsequently, unsupervised hierarchical clustering was applied on the extracted features to identify distinct phenotypic patterns of the lung parenchyma, where consensus clustering was used to identify the optimal number of clusters (K = 2). Differences between phenotypes for demographic and clinical covariates including sex, age, BMI, pack-years of smoking, Lung-RADS and cancer diagnosis were assessed for each phenotype cluster, and then compared across clusters for the two different CT reconstruction algorithms using the cluster entanglement metric, where a lower entanglement coefficient corresponds to good cluster alignment. Furthermore, an independent set of low-dose CT scans (n = 88) from patients with available pulmonary function data on lung obstruction were analyzed using the identified optimal clusters to assess associations to lung obstruction and validate the lung phenotyping paradigm. Heatmaps generated by radiomic features identified two distinct lung parenchymal phenotype patterns across different feature extraction window sizes, for both reconstruction algorithms (P < 0.05 with K = 2). Associations of radiomic-based clusters with clinical covariates showed significant differences for BMI and pack-years of smoking (P < 0.05) for both reconstruction kernels. Radiomic phenotype patterns were more similar across the two reconstructed kernels, when smaller window sizes (W = 4 and 8 mm) were used for radiomic feature extraction, as deemed by their entanglement coefficient. Validation of clustering approaches using cluster mapping for the independent sample with lung obstruction also showed two statistically significant phenotypes (P < 0.05) with significant difference for BMI and smoking pack-years. Radiomic analysis can be used to characterize lung parenchymal phenotypes from low-dose CT scans, which appear reproducible for different reconstruction kernels. Further work should seek to evaluate the effect of additional CT acquisition parameters and validate these phenotypes in characterizing lung cancer screening populations, to potentially better stratify disease patterns and cancer risk.


Assuntos
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Detecção Precoce de Câncer , Pulmão/diagnóstico por imagem , Algoritmos
14.
Can J Cardiol ; 39(1): 22-31, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36228886

RESUMO

BACKGROUND: Wide geographic variation in access to transcatheter (TAVR) and surgical (SAVR) aortic valve replacement exists, but the impact of socioethnic factors on the geographic variation of AS management in Ontario, Canada, is unknown. METHODS: Neighbourhood rates of AS admissions, as a proxy for AS burden, and downstream TAVR and SAVR referrals and procedures were estimated for the 76 subregions in Ontario. To determine if the socioethnic geographic variations in referrals and procedures were concordant or discordant with AS burden, we calculated Pearson correlation coefficients to determine the relationship between AS burden and each of TAVR referrals, TAVR procedures, SAVR referrals, or SAVR procedures. We developed generalised linear models to determine the association between social deprivation indices captured in the Ontario Marginalization index and the rates of AS burden as well as TAVR/SAVR referral and procedures. RESULTS: There was wide geographic variation that was concordant between AS burden and the referral and procedure rates for TAVR and SAVR (correlation coefficients 0.86-0.96). Increased dependency was associated with higher rates of both TAVR/SAVR referrals and procedures (rate ratios 1.63-2.22). Neighbourhoods with a higher concentration of ethnic minorities were associated with lower AS burden as well as lower rates of both SAVR and TAVR referrals and procedures (rate ratios 0.57-0.85). CONCLUSIONS: An important ethnic gradient exists in AS burden and in both referral and completion of TAVR and SAVR in Ontario. Further research is necessary to understand if this gradient is appropriate or requires mitigation.


Assuntos
Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Substituição da Valva Aórtica Transcateter , Humanos , Valva Aórtica/cirurgia , Substituição da Valva Aórtica Transcateter/métodos , Implante de Prótese de Valva Cardíaca/métodos , Estenose da Valva Aórtica/epidemiologia , Estenose da Valva Aórtica/cirurgia , Etnicidade , Resultado do Tratamento , Ontário/epidemiologia , Fatores de Risco
15.
Sci Rep ; 12(1): 19009, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36348002

RESUMO

Radiomic approaches in precision medicine are promising, but variation associated with image acquisition factors can result in severe biases and low generalizability. Multicenter datasets used in these studies are often heterogeneous in multiple imaging parameters and/or have missing information, resulting in multimodal radiomic feature distributions. ComBat is a promising harmonization tool, but it only harmonizes by single/known variables and assumes standardized input data are normally distributed. We propose a procedure that sequentially harmonizes for multiple batch effects in an optimized order, called OPNested ComBat. Furthermore, we propose to address bimodality by employing a Gaussian Mixture Model (GMM) grouping considered as either a batch variable (OPNested + GMM) or as a protected clinical covariate (OPNested - GMM). Methods were evaluated on features extracted with CapTK and PyRadiomics from two public lung computed tomography (CT) datasets. We found that OPNested ComBat improved harmonization performance over standard ComBat. OPNested + GMM ComBat exhibited the best harmonization performance but the lowest predictive performance, while OPNested - GMM ComBat showed poorer harmonization performance, but the highest predictive performance. Our findings emphasize that improved harmonization performance is no guarantee of improved predictive performance, and that these methods show promise for superior standardization of datasets heterogeneous in multiple or unknown imaging parameters and greater generalizability.


Assuntos
Tomografia Computadorizada por Raios X , Distribuição Normal
16.
iScience ; 25(10): 105234, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36267915

RESUMO

Activated-to-memory transitioning CD4+ T cells display elevated expression of the HIV-1 co-receptor CCR5 and are more prone to HIV-1 latent infection. Here, we show that p53-regulated miRNA-103 downmodulates CCR5 levels in CD4+ T lymphocytes. We reveal that miRNA-103 mimics, as well as Nutlin-3, an inhibitor of Mdm2-mediated p53 degradation, decrease CCR5-dependent HIV-1 infection. Using a dual-reporter virus, we subsequently validate that in transitioning CD4+ T cells, Nutlin-3 treatment decreases the frequency of both productively and latently infected cells via upregulation of miRNA-103. Importantly, we provide evidence that CD4+ T cells from HIV-1 elite controllers express less CCR5 than those from antiretroviral therapy-naïve progressors, an effect linked to a significant increase in miRNA-103 levels. By contributing to the control of CCR5 expression in CD4+ T cells, miRNA-103 is likely to play a key role in countering the establishment of latent HIV-1 reservoirs in vivo.

17.
Cancers (Basel) ; 14(19)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36230723

RESUMO

Despite the demonstrated potential of artificial intelligence (AI) in breast cancer risk assessment for personalizing screening recommendations, further validation is required regarding AI model bias and generalizability. We performed external validation on a U.S. screening cohort of a mammography-derived AI breast cancer risk model originally developed for European screening cohorts. We retrospectively identified 176 breast cancers with exams 3 months to 2 years prior to cancer diagnosis and a random sample of 4963 controls from women with at least one-year negative follow-up. A risk score for each woman was calculated via the AI risk model. Age-adjusted areas under the ROC curves (AUCs) were estimated for the entire cohort and separately for White and Black women. The Gail 5-year risk model was also evaluated for comparison. The overall AUC was 0.68 (95% CIs 0.64−0.72) for all women, 0.67 (0.61−0.72) for White women, and 0.70 (0.65−0.76) for Black women. The AI risk model significantly outperformed the Gail risk model for all women p < 0.01 and for Black women p < 0.01, but not for White women p = 0.38. The performance of the mammography-derived AI risk model was comparable to previously reported European validation results; non-significantly different when comparing White and Black women; and overall, significantly higher than that of the Gail model.

18.
Can J Cardiol ; 38(10 Suppl1): S30-S41, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35777682

RESUMO

The advances in percutaneous coronary intervention (PCI) have been, above all, dependent on the work of pioneers in surgery, radiology, and interventional cardiology. From Grüntzig's first balloon angioplasty, PCI has expanded through technology development, improved protocols, and dissemination of best-practice techniques. We can nowadays treat more complex lesions in higher-risk patients with favourable results. Guide wires, balloon types and profiles, debulking techniques such as atherectomy or lithotripsy, stents, and scaffolds all represent evolutions that have allowed us to tackle complex lesions such as an unprotected left main coronary artery, complex bifurcations, or chronic total occlusions. Best-practice PCI, including physiology assessment, imaging, and optimal lesion preparation are now the gold standard when performing PCI for sound indications, and new technologies such as intravascular lithotripsy for lesion preparation, or artificial intelligence, are innovations in the steps of 4 decades of pioneers to improve patient care in interventional cardiology. In the present review, major innovations in PCI since the first balloon angioplasty and also uncertainties and obstacles inherent to such medical advances are described.


Assuntos
Angioplastia Coronária com Balão , Angioplastia com Balão , Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Angioplastia Coronária com Balão/métodos , Inteligência Artificial , Angiografia Coronária/métodos , Doença da Artéria Coronariana/etiologia , Doença da Artéria Coronariana/cirurgia , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Stents , Resultado do Tratamento
19.
AIDS Res Hum Retroviruses ; 38(8): 670-682, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35778845

RESUMO

HIV cure research requires interrogating latent HIV reservoirs in deep tissues, which necessitates autopsies to avoid risks to participants. An HIV autopsy biobank would facilitate this research, but such research raises ethical issues and requires participant engagement. This study explores the willingness to participate in HIV cure research at the end of life. Participants include Canadians with HIV [people with HIV (PWHIV)] aged 55 years or older. Following a mixed-method study design, all participants completed a phone or online survey, and a subset of participants participated in in-depth phone or videoconference interviews. We produced descriptive statistics of quantitative data and a thematic analysis of qualitative data. Barriers and facilitators were categorized under domains of the Theoretical Domains Framework. From April 2020 to August 2021, 37 participants completed the survey (mean age = 69.9 years old; mean duration of HIV infection = 28.5 years), including 15 interviewed participants. About three quarters of participants indicated being willing to participate in hypothetical medical studies toward the end of life (n = 30; 81.1%), in HIV biobanking (n = 30; 81.1%), and in a research autopsy (n = 28; 75.7%) to advance HIV cure research, mainly for altruistic benefits. The main perceived risks had to do with physical pain and confidentiality. Barriers and facilitators were distributed across five domains: social/professional role and identity, environmental context and resources, social influences, beliefs about consequences, and capabilities. Participants wanted more information about study objectives and procedures, possible accommodations with their last will, and rationale for studies or financial interests funding studies. Our results indicate that older PWHIV would be willing to participate in HIV cure research toward the end of life, HIV biobanking, and research autopsy. However, a dialogue should be initiated to inform participants thoroughly about HIV cure studies, address concerns, and accommodate their needs and preferences. Additional work is required, likely through increased community engagement, to address educational needs.


Assuntos
Infecções por HIV , HIV-1 , Idoso , Bancos de Espécimes Biológicos , Canadá , Morte , Infecções por HIV/tratamento farmacológico , Humanos , Pesquisa Qualitativa , Latência Viral
20.
Sci Rep ; 12(1): 9993, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35705618

RESUMO

We aim to determine the feasibility of a novel radiomic biomarker that can integrate with other established clinical prognostic factors to predict progression-free survival (PFS) in patients with non-small cell lung cancer (NSCLC) undergoing first-line immunotherapy. Our study includes 107 patients with stage 4 NSCLC treated with pembrolizumab-based therapy (monotherapy: 30%, combination chemotherapy: 70%). The ITK-SNAP software was used for 3D tumor volume segmentation from pre-therapy CT scans. Radiomic features (n = 102) were extracted using the CaPTk software. Impact of heterogeneity introduced by image physical dimensions (voxel spacing parameters) and acquisition parameters (contrast enhancement and CT reconstruction kernel) was mitigated by resampling the images to the minimum voxel spacing parameters and harmonization by a nested ComBat technique. This technique was initialized with radiomic features, clinical factors of age, sex, race, PD-L1 expression, ECOG status, body mass index (BMI), smoking status, recurrence event and months of progression-free survival, and image acquisition parameters as batch variables. Two phenotypes were identified using unsupervised hierarchical clustering of harmonized features. Prognostic factors, including PDL1 expression, ECOG status, BMI and smoking status, were combined with radiomic phenotypes in Cox regression models of PFS and Kaplan Meier (KM) curve-fitting. Cox model based on clinical factors had a c-statistic of 0.57, which increased to 0.63 upon addition of phenotypes derived from harmonized features. There were statistically significant differences in survival outcomes stratified by clinical covariates, as measured by the log-rank test (p = 0.034), which improved upon addition of phenotypes (p = 0.00022). We found that mitigation of heterogeneity by image resampling and nested ComBat harmonization improves prognostic value of phenotypes, resulting in better prediction of PFS when added to other prognostic variables.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Biomarcadores , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Imunoterapia/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/tratamento farmacológico , Intervalo Livre de Progressão
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