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1.
Proc Natl Acad Sci U S A ; 119(26): e2116738119, 2022 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-35749366

RESUMEN

Tumor infiltration by T cells profoundly affects cancer progression and responses to immunotherapy. However, the tumor immunosuppressive microenvironment can impair the induction, trafficking, and local activity of antitumor T cells. Here, we investigated whether intratumoral injection of virus-derived peptide epitopes could activate preexisting antiviral T cell responses locally and promote antitumor responses or antigen spreading. We focused on a mouse model of cytomegalovirus (CMV), a highly prevalent human infection that induces vigorous and durable T cell responses. Mice persistently infected with murine CMV (MCMV) were challenged with lung (TC-1), colon (MC-38), or melanoma (B16-F10) tumor cells. Intratumoral injection of MCMV-derived T cell epitopes triggered in situ and systemic expansion of their cognate, MCMV-specific CD4+ or CD8+ T cells. The MCMV CD8+ T cell epitopes injected alone provoked arrest of tumor growth and some durable remissions. Intratumoral injection of MCMV CD4+ T cell epitopes with polyinosinic acid:polycytidylic acid (pI:C) preferentially elicited tumor antigen-specific CD8+ T cells, promoted tumor clearance, and conferred long-term protection against tumor rechallenge. Notably, secondary proliferation of MCMV-specific CD8+ T cells correlated with better tumor control. Importantly, intratumoral injection of MCMV-derived CD8+ T cell-peptide epitopes alone or CD4+ T cell-peptide epitopes with pI:C induced potent adaptive and innate immune activation of the tumor microenvironment. Thus, CMV-derived peptide epitopes, delivered intratumorally, act as cytotoxic and immunotherapeutic agents to promote immediate tumor control and long-term antitumor immunity that could be used as a stand-alone therapy. The tumor antigen-agnostic nature of this approach makes it applicable across a broad range of solid tumors regardless of their origin.


Asunto(s)
Linfocitos T CD8-positivos , Infecciones por Citomegalovirus , Citomegalovirus , Epítopos de Linfocito T , Neoplasias , Animales , Antígenos de Neoplasias/inmunología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Citomegalovirus/inmunología , Infecciones por Citomegalovirus/inmunología , Epítopos de Linfocito T/administración & dosificación , Epítopos de Linfocito T/inmunología , Inmunoterapia , Ratones , Neoplasias/inmunología , Neoplasias/terapia , Poli I-C/administración & dosificación , Poli I-C/inmunología , Microambiente Tumoral
2.
Respir Res ; 25(1): 106, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38419014

RESUMEN

BACKGROUND: Small airways disease (SAD) is a major cause of airflow obstruction in COPD patients and has been identified as a precursor to emphysema. Although the amount of SAD in the lungs can be quantified using our Parametric Response Mapping (PRM) approach, the full breadth of this readout as a measure of emphysema and COPD progression has yet to be explored. We evaluated topological features of PRM-derived normal parenchyma and SAD as surrogates of emphysema and predictors of spirometric decline. METHODS: PRM metrics of normal lung (PRMNorm) and functional SAD (PRMfSAD) were generated from CT scans collected as part of the COPDGene study (n = 8956). Volume density (V) and Euler-Poincaré Characteristic (χ) image maps, measures of the extent and coalescence of pocket formations (i.e., topologies), respectively, were determined for both PRMNorm and PRMfSAD. Association with COPD severity, emphysema, and spirometric measures were assessed via multivariable regression models. Readouts were evaluated as inputs for predicting FEV1 decline using a machine learning model. RESULTS: Multivariable cross-sectional analysis of COPD subjects showed that V and χ measures for PRMfSAD and PRMNorm were independently associated with the amount of emphysema. Readouts χfSAD (ß of 0.106, p < 0.001) and VfSAD (ß of 0.065, p = 0.004) were also independently associated with FEV1% predicted. The machine learning model using PRM topologies as inputs predicted FEV1 decline over five years with an AUC of 0.69. CONCLUSIONS: We demonstrated that V and χ of fSAD and Norm have independent value when associated with lung function and emphysema. In addition, we demonstrated that these readouts are predictive of spirometric decline when used as inputs in a ML model. Our topological PRM approach using PRMfSAD and PRMNorm may show promise as an early indicator of emphysema onset and COPD progression.


Asunto(s)
Enfisema , Enfermedad Pulmonar Obstructiva Crónica , Enfisema Pulmonar , Humanos , Estudios Transversales , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Volumen Espiratorio Forzado/fisiología
3.
Pediatr Res ; 95(1): 59-69, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37674023

RESUMEN

The neurovascular unit (NVU) within the brain is a multicellular unit that synergistically acts to maintain blood-brain barrier function and meet cerebral metabolic demand. Recent studies have indicated disruption to the NVU is associated with neuropathology in the perinatal brain. Infants with fetal growth restriction (FGR) are known to be at increased risk of neurodevelopmental conditions including motor, learning, and behavioural deficits. There are currently no neuroprotective treatments for these conditions. In this review, we analyse large animal studies examining the effects of FGR on the perinatal NVU. These studies show altered vascularity in the FGR brain as well as blood-brain barrier dysfunction due to underlying cellular changes, mediated by neuroinflammation. Neuroinflammation is a key mechanism associated with pathological effects in the FGR brain. Hence, targeting inflammation may be key to preserving the multicellular NVU and providing neuroprotection in FGR. A number of maternal and postnatal therapies with anti-inflammatory components have been investigated in FGR animal models examining targets for amelioration of NVU disruption. Each therapy showed promise by uniquely ameliorating the adverse effects of FGR on multiple aspects of the NVU. The successful implementation of a clinically viable neuroprotective treatment has the potential to improve outcomes for neonates affected by FGR. IMPACT: Disruption to the neurovascular unit is associated with neuropathology in fetal growth restriction. Inflammation is a key mechanism associated with neurovascular unit disruption in the growth-restricted brain. Anti-inflammatory treatments ameliorate adverse effects on the neurovascular unit and may provide neuroprotection.


Asunto(s)
Retardo del Crecimiento Fetal , Enfermedades Neuroinflamatorias , Embarazo , Animales , Recién Nacido , Lactante , Femenino , Humanos , Encéfalo/metabolismo , Barrera Hematoencefálica , Antiinflamatorios/uso terapéutico
4.
Prostate ; 83(10): 922-928, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37078628

RESUMEN

INTRODUCTION: The University of California, San Francisco Cancer of the Prostate Risk Assessment (CAPRA) score is a validated tool using factors at diagnosis to predict prostate cancer outcomes after radical prostatectomy (RP). This study evaluates whether substitution of prostate-specific antigen (PSA) density for serum PSA improves predictive performance of the clinical CAPRA model. METHODS: Participants were diagnosed in 2000-2019 with stage T1/T2 cancer, underwent RP, with at least a 6-month follow-up. We computed standard CAPRA score using diagnostic age, Gleason grade, percent positive cores, clinical T stage, and serum PSA, and an alternate score using similar variables but substituting PSA density for PSA. We reported CAPRA categories as low (0-2), intermediate (3-5), and high (6-10) risk. Recurrence was defined as two consecutive PSA ≥ 0.2 ng/mL or receipt of salvage treatment. Life table and Kaplan-Meier analysis evaluated recurrence-free survival after prostatectomy. Cox proportional hazards regression models tested associations of standard or alternate CAPRA variables with recurrence risk. Additional models tested associations between standard or alternate CAPRA score with recurrence risk. Cox log-likelihood ratio test (-2 LOG L) assessed model accuracy. RESULTS: A total of 2880 patients had median age 62 years, GG1 30% and GG2 31%, median PSA 6.5, and median PSA density 0.19. Median postoperative follow-up was 45 months. Alternate CAPRA model was associated with shifts in risk scores, with 16% of patients increasing and 7% decreasing (p < 0.01). Recurrence-free survival after RP was 75% at 5 years and 62% at 10 years. Both CAPRA component models were associated with recurrence risk after RP on Cox regression. Covariate fit statistics showed better fit for standard CAPRA model versus alternate (p < 0.01). Standard (hazard ratio [HR]: 1.55; 95% confidence interval [CI]: 1.50-1.61) and alternate (HR: 1.50; 95% CI: 1.44-1.55) CAPRA scores were associated with recurrence risk, with better fit for standard model (p < 0.01). CONCLUSIONS: In a 2880 patient cohort followed for median 45 months after RP, alternate CAPRA model using PSA density was associated with higher biochemical recurrence (BCR) risk, but performed inferior to standard CAPRA at predicting BCR. While PSA density is an established prognostic variable in prediagnostic settings and sub-stratifying low-risk disease, it does not improve BCR model predictive accuracy when applied across a range of cancer risk.


Asunto(s)
Antígeno Prostático Específico , Neoplasias de la Próstata , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico , Recurrencia Local de Neoplasia/cirugía , Pronóstico , Próstata , Prostatectomía , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/cirugía , Medición de Riesgo
5.
Oncologist ; 28(6): 510-519, 2023 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-36848266

RESUMEN

BACKGROUND: Female underrepresentation in oncology clinical trials can result in outcome disparities. We evaluated female participant representation in US oncology trials by intervention type, cancer site, and funding. MATERIALS AND METHODS: Data were extracted from the publicly available Aggregate Analysis of ClinicalTrials.gov database. Initially, 270,172 studies were identified. Following the exclusion of trials using Medical Subject Heading terms, manual review, those with incomplete status, non-US location, sex-specific organ cancers, or lacking participant sex data, 1650 trials consisting of 240,776 participants remained. The primary outcome was participation to prevalence ratio (PPR): percent females among trial participants divided by percent females in the disease population per US Surveillance, Epidemiology, and End Results Program data. PPRs of 0.8-1.2 reflect proportional female representation. RESULTS: Females represented 46.9% of participants (95% CI, 45.4-48.4); mean PPR for all trials was 0.912. Females were underrepresented in surgical (PPR 0.74) and other invasive (PPR 0.69) oncology trials. Among cancer sites, females were underrepresented in bladder (odds ratio [OR] 0.48, 95% CI 0.26-0.91, P = .02), head/neck (OR 0.44, 95% CI 0.29-0.68, P < .01), stomach (OR 0.40, 95% CI 0.23-0.70, P < .01), and esophageal (OR 0.40 95% CI 0.22-0.74, P < .01) trials. Hematologic (OR 1.78, 95% CI 1.09-1.82, P < .01) and pancreatic (OR 2.18, 95% CI 1.46-3.26, P < .01) trials had higher odds of proportional female representation. Industry-funded trials had greater odds of proportional female representation (OR 1.41, 95% CI 1.09-1.82, P = .01) than US government and academic-funded trials. CONCLUSIONS: Stakeholders should look to hematologic, pancreatic, and industry-funded cancer trials as exemplars of female participant representation and consider female representation when interpreting trial results.


Asunto(s)
Neoplasias , Masculino , Humanos , Femenino , Estados Unidos/epidemiología , Neoplasias/epidemiología , Neoplasias/terapia , Oncología Médica , Oportunidad Relativa , Bases de Datos Factuales , Prevalencia
6.
J Urol ; 207(5): 1001-1009, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34981949

RESUMEN

PURPOSE: For men with clinically localized prostate cancer outcomes of continuing active surveillance (AS) after biopsy progression are not well understood. We aim to determine the impact of continuing AS and delayed definitive treatment after biopsy progression on oncologic outcomes. MATERIALS AND METHODS: Participants in our prospective AS cohort (1990-2018) diagnosed with grade group (GG) 1, localized prostate cancer, with prostate specific antigen <20 who were subsequently upgraded to ≥GG2, and underwent further surveillance (biopsy/imaging/prostate specific antigen) were identified. Patients were stratified by post-progression followup into 3 groups: continue AS untreated, pursue early radical prostatectomy (RP) ≤6 months, or undergo late RP within 6 months to 5 years of progression. Patients receiving other treatments were excluded. We compared characteristics between groups and examined the associations of early vs late RP with risk of adverse pathology (AP) at RP and recurrence-free survival (RFS) after RP. RESULTS: Of 531 patients with biopsy progression and further surveillance 214 (40%) remained untreated, 192 (36%) pursued early RP and 125 (24%) underwent late RP. Among patients who underwent early vs late RP, there was no difference in GG (p=0.15) or AP (55% vs 53%, p=0.74) rate at RP, or 3-year RFS (80% vs 87%, log-rank p=0.64) after RP. In multivariable models, only Cancer of Prostate Risk Assessment post-surgical score was associated with risk of RFS (HR=1.42 per point, 95% CI 1.24-1.64). CONCLUSIONS: Among patients continuing AS after biopsy progression, 60% underwent surgery within 5 years. Delayed surgery after progression was not associated with higher risk of AP or RFS. This suggests select patients may be able to safely delay treatment after progression.


Asunto(s)
Antígeno Prostático Específico , Neoplasias de la Próstata , Biopsia , Humanos , Masculino , Clasificación del Tumor , Estudios Prospectivos , Prostatectomía , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/cirugía , Espera Vigilante
7.
J Urol ; 205(4): 1159-1168, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33079618

RESUMEN

PURPOSE: Clinical trials require significant resources, but benefits are only realized after trial completion and dissemination of results. We comprehensively assessed early discontinuation, registry results reporting, and publication by trial sponsor and subspecialty in urology trials. MATERIALS AND METHODS: We assessed trial registrations from 2007 to 2019 on ClinicalTrials.gov and publication data from PubMed®/MEDLINE®. Associations between sponsor or subspecialty with early discontinuation were assessed using Cox proportional hazards and results reporting or publication with logistic regression at 3 years after completion. RESULTS: Of 8,636 trials 3,541 (41.0%) were completed and 999 (11.6%) were discontinued. Of completed trials 26.9% reported results and 21.6% were published. Sponsors included academic institutions (53.1%), industry (37.1%) and the U.S. government (9.8%). Academic-sponsored (adjusted HR 0.81, 95% CI 0.69-0.96, p=0.012) and government-sponsored trials (adjusted HR 0.62, 95% CI 0.49-0.78, p <0.001) were less likely than industry to discontinue early. Government-sponsored trials were more likely to report (adjusted OR 1.72, 95% CI 1.17-2.54, p=0.006) and publish (adjusted OR 1.89, 95% CI 1.23-2.89, p=0.004). Academic-sponsored trials were less likely to report (adjusted OR 0.65, CI:0.48-0.88, p=0.006) but more likely to publish (adjusted OR 1.72, 95% CI 1.25-2.37, p <0.001). These outcomes were similar across subspecialties. However, endourology was more likely to discontinue early (adjusted HR 2.00, 95% CI 1.53-2.95, p <0.001), general urology was more likely to report results (adjusted OR 1.54, 95% CI 1.13-2.11, p=0.006) and andrology was less likely to publish (adjusted OR 0.53, 95% CI 0.35-0.81, p=0.003). CONCLUSIONS: Sponsor type is significantly associated with trial completion and dissemination. Government-sponsored trials had the best performance, while industry and academic-sponsored trials lagged in completion and results reporting, respectively. Subspecialty played a lesser role. Lack of dissemination remains a problem for urology trials.


Asunto(s)
Ensayos Clínicos como Asunto , Urología , Bases de Datos Factuales , Humanos , Difusión de la Información , Publicaciones Periódicas como Asunto , Edición , Sistema de Registros , Estados Unidos
8.
BMC Public Health ; 21(1): 1289, 2021 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-34210304

RESUMEN

BACKGROUND: This study evaluates the role of social isolation on inflammation and cancer mortality among women. METHODS: Data were abstracted from the U.S. National Health and Nutrition Examination Survey from 1988 to 1994. The Social Network Index was used to assess participants' degree of social isolation. C-reactive protein and fibrinogen levels were included as markers of inflammation. We used the National Death Index to identify causes and dates of mortality. Chi-square and multivariable Cox regressions were employed for statistical analyses. RESULTS: Of 3360 women (median age: 54 years), the most isolated, very isolated, somewhat isolated, and not isolated comprised 14.5, 30.2, 37.1, and 18.2% of the sample, respectively. The most isolated participants were more likely to have low income (56.8% vs 12.2%, p < 0.001), have fewer years of education (40.8% vs 12.3%; p < 0.001), have low physical activity (27.3% vs 14.7%; p < 0.003), be obese (32.5% vs 24.4%; p = 0.02), and be current smokers (34.2% vs 10.3%; p < 0.001) compared to the not isolated ones. Mean fibrinogen levels increased with degree of social isolation (p = 0.003), but C-reactive protein showed no association (p = 0.52). Kaplan-Meier estimates indicated higher cancer mortality rates among participants with elevated fibrinogen levels, though not with statistical significance (p = 0.08). Furthermore, there was no association between social isolation and cancer mortality (p = 0.54). On multivariate analysis, obesity (HR = 1.56; 95% CI: 1.11-2.18), higher education (HR = 1.36; 95% CI: 1.01-1.83), and smoking (HR = 4.42, 95% CI: 2.84-6.88) were independent predictors for cancer mortality, while high physical activity predicted for lower mortality from cancer (HR = 0.67, 95% CI: 0.51-0.87). However, social isolation was not a predictor. CONCLUSION: Social isolation among women was associated with an increased level of fibrinogen, but not associated with cancer mortality. The relationship between inflammation and cancer mortality warrants further investigation.


Asunto(s)
Neoplasias , Aislamiento Social , Proteína C-Reactiva/análisis , Femenino , Humanos , Inflamación/epidemiología , Persona de Mediana Edad , Encuestas Nutricionales
10.
Adv Physiol Educ ; 43(1): 76-81, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30694707

RESUMEN

Evidence shows that biomedical knowledge is more effectively taught within the medical curriculum by teaching in context, to facilitate learning transfer. The purpose of the present study was to evaluate the effect of combining high-technology simulation and physiology teaching on medical student learning and experience. First-year medical students received respiratory physiology teaching in the form of lectures, problem-based learning, and practical sessions. These students were then given the opportunity to apply their knowledge and problem solve using respiratory-related clinical case scenarios in simulated patients. Student understanding was assessed using a short quiz performed immediately before and after the session. Results revealed that the session significantly improved the mean score on tests (6.97 ± 0.29 vs. 8.22 ± 0.19, P < 0.001). Student evaluation was collected in focus groups, and recurring concepts were extracted from the data. Students reported that the sessions helped to bridge the gap between theory and practice, which aided their learning. In addition, this teaching methodology (simulation) was reportedly patient centered and added to the realism of the simulated scenario, with students stating that this teaching improved their confidence with managing real patients and clinical uncertainty. Simulation has been used extensively to teach clinical skills; however, research regarding its potential for teaching biomedical science within a clinical context is limited. Our study shows that combining high-technology simulation and physiology teaching contributed to an immediate improvement in medical student knowledge and enhanced their ability to make connections between theoretical knowledge and the world of practice.


Asunto(s)
Educación de Pregrado en Medicina/métodos , Evaluación Educacional/métodos , Fisiología/educación , Aprendizaje Basado en Problemas/métodos , Mecánica Respiratoria/fisiología , Estudiantes de Medicina , Femenino , Humanos , Masculino
11.
Am J Pathol ; 187(9): 1984-1997, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28683257

RESUMEN

Chylous pleural effusion (chylothorax) frequently accompanies lymphatic vessel malformations and other conditions with lymphatic defects. Although retrograde flow of chyle from the thoracic duct is considered a potential mechanism underlying chylothorax in patients and mouse models, the path chyle takes to reach the thoracic cavity is unclear. Herein, we use a novel transgenic mouse model, where doxycycline-induced overexpression of vascular endothelial growth factor (VEGF)-C was driven by the adipocyte-specific promoter adiponectin (ADN), to determine how chylothorax forms. Surprisingly, 100% of adult ADN-VEGF-C mice developed chylothorax within 7 days. Rapid, consistent appearance of chylothorax enabled us to examine the step-by-step development in otherwise normal adult mice. Dynamic imaging with a fluorescent tracer revealed that lymph in the thoracic duct of these mice could enter the thoracic cavity by retrograde flow into enlarged paravertebral lymphatics and subpleural lymphatic plexuses that had incompetent lymphatic valves. Pleural mesothelium overlying the lymphatic plexuses underwent exfoliation that increased during doxycycline exposure. Together, the findings indicate that chylothorax in ADN-VEGF-C mice results from retrograde flow of chyle from the thoracic duct into lymphatic tributaries with defective valves. Chyle extravasates from these plexuses and enters the thoracic cavity through exfoliated regions of the pleural mesothelium.


Asunto(s)
Quilotórax/genética , Sistema Linfático/anomalías , Factor C de Crecimiento Endotelial Vascular/genética , Animales , Quilotórax/patología , Vasos Linfáticos/anomalías , Ratones , Ratones Transgénicos
14.
Curr Opin Cell Biol ; 19(4): 376-85, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17689063

RESUMEN

The elucidation of a complete, accurate, and permanent representation of the proteome of the mammalian cell may be achievable piecemeal by an organellar based approach. The small volume of organelles assures high protein concentrations. Providing isolated organelles are homogenous, this assures reliable protein characterization within the sensitivity and dynamic range limits of current mass spec based analysis. The stochastic aspect of peptide selection by tandem mass spectrometry for sequence determination by fragmentation is dealt with by multiple biological replicates as well as by prior protein separation on 1-D gels. Applications of this methodology to isolated synaptic vesicles, clathrin coated vesicles, endosomes, phagosomes, endoplasmic reticulum, and Golgi apparatus, as well as Golgi-derived COPI vesicles, have led to mechanistic insight into the identity and function of these organelles.


Asunto(s)
Células/química , Orgánulos , Proteómica , Vesículas Sinápticas/química , Animales , Endosomas/química , Endosomas/fisiología , Células HeLa , Humanos , Modelos Biológicos , Orgánulos/fisiología , Fagosomas/química , Fagosomas/fisiología , Ratas , Vesículas Sinápticas/fisiología
15.
Acad Radiol ; 31(3): 1148-1159, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37661554

RESUMEN

RATIONALE AND OBJECTIVES: Small airways disease (SAD) and emphysema are significant components of chronic obstructive pulmonary disease (COPD), a heterogenous disease where predicting progression is difficult. SAD, a principal cause of airflow obstruction in mild COPD, has been identified as a precursor to emphysema. Parametric Response Mapping (PRM) of chest computed tomography (CT) can help distinguish SAD from emphysema. Specifically, topologic PRM can define local patterns of both diseases to characterize how and in whom COPD progresses. We aimed to determine if distribution of CT-based PRM of functional SAD (fSAD) is associated with emphysema progression. MATERIALS AND METHODS: We analyzed paired inspiratory-expiratory chest CT scans at baseline and 5-year follow up in 1495 COPDGene subjects using topological analyses of PRM classifications. By spatially aligning temporal scans, we mapped local emphysema at year five to baseline lobar PRM-derived topological readouts. K-means clustering was applied to all observations. Subjects were subtyped based on predominant PRM cluster assignments and assessed using non-parametric statistical tests to determine differences in PRM values, pulmonary function metrics, and clinical measures. RESULTS: We identified distinct lobar imaging patterns and classified subjects into three radiologic subtypes: emphysema-dominant (ED), fSAD-dominant (FD), and fSAD-transition (FT: transition from healthy lung to fSAD). Relative to year five emphysema, FT showed rapid local emphysema progression (-57.5% ± 1.1) compared to FD (-49.9% ± 0.5) and ED (-33.1% ± 0.4). FT consisted primarily of at-risk subjects (roughly 60%) with normal spirometry. CONCLUSION: The FT subtype of COPD may allow earlier identification of individuals without spirometrically-defined COPD at-risk for developing emphysema.


Asunto(s)
Enfisema , Enfermedad Pulmonar Obstructiva Crónica , Enfisema Pulmonar , Humanos , Enfisema Pulmonar/diagnóstico por imagen , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos
16.
J Heart Lung Transplant ; 43(3): 394-402, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37778525

RESUMEN

BACKGROUND: Assessment and selection of donor lungs remain largely subjective and experience based. Criteria to accept or decline lungs are poorly standardized and are not compliant with the current donor pool. Using ex vivo computed tomography (CT) images, we investigated the use of a CT-based machine learning algorithm for screening donor lungs before transplantation. METHODS: Clinical measures and ex situ CT scans were collected from 100 cases as part of a prospective clinical trial. Following procurement, donor lungs were inflated, placed on ice according to routine clinical practice, and imaged using a clinical CT scanner before transplantation while stored in the icebox. We trained and tested a supervised machine learning method called dictionary learning, which uses CT scans and learns specific image patterns and features pertaining to each class for a classification task. The results were evaluated with donor and recipient clinical measures. RESULTS: Of the 100 lung pairs donated, 70 were considered acceptable for transplantation (based on standard clinical assessment) before CT screening and were consequently implanted. The remaining 30 pairs were screened but not transplanted. Our machine learning algorithm was able to detect pulmonary abnormalities on the CT scans. Among the patients who received donor lungs, our algorithm identified recipients who had extended stays in the intensive care unit and were at 19 times higher risk of developing chronic lung allograft dysfunction within 2 years posttransplant. CONCLUSIONS: We have created a strategy to ex vivo screen donor lungs using a CT-based machine learning algorithm. As the use of suboptimal donor lungs rises, it is important to have in place objective techniques that will assist physicians in accurately screening donor lungs to identify recipients most at risk of posttransplant complications.


Asunto(s)
Trasplante de Pulmón , Donantes de Tejidos , Humanos , Pulmón/diagnóstico por imagen , Aprendizaje Automático , Estudios Prospectivos , Tomografía Computarizada por Rayos X , Ensayos Clínicos como Asunto
17.
bioRxiv ; 2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36712023

RESUMEN

Novel immunotherapy combination therapies have improved outcomes for patients with hepatocellular carcinoma (HCC), but responses are limited to a subset of patients and recurrence can also occur. Little is known about the inter- and intra-tumor heterogeneity in cellular signaling networks within the HCC tumor microenvironment (TME) that underlie responses to modern systemic therapy. We applied spatial transcriptomics (ST) profiling to characterize the tumor microenvironment in HCC resection specimens from a clinical trial of neoadjuvant cabozantinib, a multi-tyrosine kinase inhibitor that primarily blocks VEGF, and nivolumab, a PD-1 inhibitor in which 5 out of 15 patients were found to have a pathologic response. ST profiling demonstrated that the TME of responding tumors was enriched for immune cells and cancer associated fibroblasts (CAF) with pro-inflammatory signaling relative to the non-responders. The enriched cancer-immune interactions in responding tumors are characterized by activation of the PAX5 module, a known regulator of B cell maturation, which colocalized with spots with increased B cell markers expression suggesting strong activity of these cells. Cancer-CAF interactions were also enriched in the responding tumors and were associated with extracellular matrix (ECM) remodeling as there was high activation of FOS and JUN in CAFs adjacent to tumor. The ECM remodeling is consistent with proliferative fibrosis in association with immune-mediated tumor regression. Among the patients with major pathologic response, a single patient experienced early HCC recurrence. ST analysis of this clinical outlier demonstrated marked tumor heterogeneity, with a distinctive immune-poor tumor region that resembles the non-responding TME across patients and was characterized by cancer-CAF interactions and expression of cancer stem cell markers, potentially mediating early tumor immune escape and recurrence in this patient. These data show that responses to modern systemic therapy in HCC are associated with distinctive molecular and cellular landscapes and provide new targets to enhance and prolong responses to systemic therapy in HCC.

18.
Stem Cell Res Ther ; 14(1): 29, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36788590

RESUMEN

BACKGROUND: Fetal growth restriction (FGR) is associated with deficits in the developing brain, including neurovascular unit (NVU) dysfunction. Endothelial colony forming cells (ECFC) can mediate improved vascular stability, and have demonstrated potential to enhance vascular development and protection. This investigation examined whether ECFCs from human umbilical cord blood (UCB) enhanced NVU development in FGR and appropriate for gestational age (AGA) fetal sheep. METHODS: Twin-bearing ewes had surgery performed at 88-90 days' gestation, inducing FGR in one fetus. At 113 days, ECFCs (1 × 107 cells) cultured from human UCB were administered intravenously to fetal sheep in utero. At 127 days, ewes and their fetuses were euthanised, fetal brains collected, and NVU components analysed by immunohistochemistry. RESULTS: Twenty-four fetal lambs, arranged in four groups: AGA (n = 7), FGR (n = 5), AGA + ECFC (n = 6), and FGR + ECFC (n = 6), were included in analyses. FGR resulted in lower body weight than AGA (P = 0.002) with higher brain/body weight ratio (P = 0.003). ECFC treatment was associated with increased vascular density throughout the brain in both AGA + ECFC and FGR + ECFC groups, as well as increased vascular-astrocyte coverage and VEGF expression in the cortex (P = 0.003, P = 0.0006, respectively) and in the subcortical white matter (P = 0.01, P = 0.0002, respectively) when compared with the untreated groups. CONCLUSIONS: ECFC administration enhanced development of NVU components in both the AGA and FGR fetal brain. Further investigation is required to assess how to optimise the enhanced angiogenic capabilities of ECFCs to provide a therapeutic strategy to protect the developing NVU against vulnerabilities associated with FGR.


Asunto(s)
Lesiones Encefálicas , Encéfalo , Animales , Ovinos , Femenino , Humanos , Animales Recién Nacidos , Feto , Lesiones Encefálicas/metabolismo , Retardo del Crecimiento Fetal/metabolismo , Sangre Fetal/metabolismo , Peso Corporal
19.
Front Physiol ; 14: 1144192, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37153221

RESUMEN

Purpose: The purpose of this study was to train and validate machine learning models for predicting rapid decline of forced expiratory volume in 1 s (FEV1) in individuals with a smoking history at-risk-for chronic obstructive pulmonary disease (COPD), Global Initiative for Chronic Obstructive Lung Disease (GOLD 0), or with mild-to-moderate (GOLD 1-2) COPD. We trained multiple models to predict rapid FEV1 decline using demographic, clinical and radiologic biomarker data. Training and internal validation data were obtained from the COPDGene study and prediction models were validated against the SPIROMICS cohort. Methods: We used GOLD 0-2 participants (n = 3,821) from COPDGene (60.0 ± 8.8 years, 49.9% male) for variable selection and model training. Accelerated lung function decline was defined as a mean drop in FEV1% predicted of > 1.5%/year at 5-year follow-up. We built logistic regression models predicting accelerated decline based on 22 chest CT imaging biomarker, pulmonary function, symptom, and demographic features. Models were validated using n = 885 SPIROMICS subjects (63.6 ± 8.6 years, 47.8% male). Results: The most important variables for predicting FEV1 decline in GOLD 0 participants were bronchodilator responsiveness (BDR), post bronchodilator FEV1% predicted (FEV1.pp.post), and CT-derived expiratory lung volume; among GOLD 1 and 2 subjects, they were BDR, age, and PRMlower lobes fSAD. In the validation cohort, GOLD 0 and GOLD 1-2 full variable models had significant predictive performance with AUCs of 0.620 ± 0.081 (p = 0.041) and 0.640 ± 0.059 (p < 0.001). Subjects with higher model-derived risk scores had significantly greater odds of FEV1 decline than those with lower scores. Conclusion: Predicting FEV1 decline in at-risk patients remains challenging but a combination of clinical, physiologic and imaging variables provided the best performance across two COPD cohorts.

20.
Neoplasia ; 42: 100911, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37269818

RESUMEN

Early detection of lung cancer is critical for improvement of patient survival. To address the clinical need for efficacious treatments, genetically engineered mouse models (GEMM) have become integral in identifying and evaluating the molecular underpinnings of this complex disease that may be exploited as therapeutic targets. Assessment of GEMM tumor burden on histopathological sections performed by manual inspection is both time consuming and prone to subjective bias. Therefore, an interplay of needs and challenges exists for computer-aided diagnostic tools, for accurate and efficient analysis of these histopathology images. In this paper, we propose a simple machine learning approach called the graph-based sparse principal component analysis (GS-PCA) network, for automated detection of cancerous lesions on histological lung slides stained by hematoxylin and eosin (H&E). Our method comprises four steps: 1) cascaded graph-based sparse PCA, 2) PCA binary hashing, 3) block-wise histograms, and 4) support vector machine (SVM) classification. In our proposed architecture, graph-based sparse PCA is employed to learn the filter banks of the multiple stages of a convolutional network. This is followed by PCA hashing and block histograms for indexing and pooling. The meaningful features extracted from this GS-PCA are then fed to an SVM classifier. We evaluate the performance of the proposed algorithm on H&E slides obtained from an inducible K-rasG12D lung cancer mouse model using precision/recall rates, Fß-score, Tanimoto coefficient, and area under the curve (AUC) of the receiver operator characteristic (ROC) and show that our algorithm is efficient and provides improved detection accuracy compared to existing algorithms.


Asunto(s)
Algoritmos , Neoplasias Pulmonares , Animales , Ratones , Neoplasias Pulmonares/diagnóstico , Aprendizaje Automático , Resultado del Tratamiento , Pulmón
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