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1.
Am Nat ; 199(4): 523-550, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35324378

RESUMO

AbstractThe distributions of marine ectotherms are governed by physiological sensitivities to long-term trends in seawater temperature and dissolved oxygen. Short-term variability in these parameters has the potential to facilitate rapid range expansions, and the resulting ecological and socioeconomic consequences may portend those of future marine communities. Here, we combine physiological experiments with ecological and demographic surveys to assess the causes and consequences of sudden but temporary poleward range expansions of a marine ectotherm with considerable life history plasticity (California market squid, Doryteuthis opalescens). We show that sequential factors related to resource accessibility in the core range-the buildup of large populations as a result of competitive release and climate-associated temperature increase and oxygen loss that constrain aerobic activity-may drive these expansions. We also reveal that poleward range expansion alters the body size-and therefore trophic role-of invading populations, with potential negative implications for socioeconomically valuable resident species. To help forecast rapid range expansions of marine ectotherms, we advocate that research efforts focus on factors impacting resource accessibility in core ranges. Determining how environmental conditions in receiving ecosystems affect body size and how body size is related to trophic role will help refine estimates of the impacts of future marine communities.


Assuntos
Ecossistema , Oxigênio , Animais , Demografia , Feminino , Gravidez , Água do Mar , Temperatura
2.
Int J Cancer ; 148(10): 2571-2578, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33368249

RESUMO

Cervical cancer remains a leading cause of cancer death for women in low- and middle-income countries. The goal of our study was to evaluate screening and triage strategies, including high-resolution microendoscopy (HRME), to detect cervical abnormalities concerning for precancer at the point of care. Women (n = 1824) were enrolled at the Instituto de Cáncer de El Salvador. All underwent screening by both human papillomavirus (HPV) testing using careHPV and visual inspection with acetic acid (VIA). Screen-positives, along with 10% of screen-negatives, were invited to return for a follow-up examination that included triage with VIA, colposcopy and HRME imaging. Biopsies were taken of any abnormalities identified. If no abnormalities were identified, then the worst scoring site by HRME was biopsied. The sensitivities of HPV testing and VIA to screen for cervical intraepithelial neoplasia Grade 2 or more severe diagnoses (CIN2+) were 82.1% and 75% (P = .77), while the specificities were 90.4% and 80.9% (P < .001), respectively. The sensitivities of VIA, colposcopy and HRME as triage tests for CIN2+ were 82.1%, 82.1% and 71.4%, respectively (P ≥ .38). HRME had a significantly higher specificity (66.7%) than VIA (51.9%) (P < .001) and colposcopy (53.3%) (P < .001). When evaluating different theoretical screening and triage strategies, screening with HPV testing followed by triage with HRME would result in more women receiving appropriate care (97%) compared to screening with VIA (75%) or HPV alone (90%). Our findings demonstrate that screening with HPV is superior to VIA, and that triage with HRME imaging increases the specificity of detecting CIN2+ at the point of care in a low-resource setting.

3.
Int J Cancer ; 149(2): 431-441, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33811763

RESUMO

We conducted a prospective evaluation of the diagnostic performance of high-resolution microendoscopy (HRME) to detect cervical intraepithelial neoplasia (CIN) in women with abnormal screening tests. Study participants underwent colposcopy, HRME and cervical biopsy. The prospective diagnostic performance of HRME using an automated morphologic image analysis algorithm was compared to that of colposcopy using histopathologic detection of CIN as the gold standard. To assess the potential to further improve performance of HRME image analysis, we also conducted a retrospective analysis assessing performance of a multi-task convolutional neural network to segment and classify HRME images. One thousand four hundred eighty-six subjects completed the study; 435 (29%) subjects had CIN Grade 2 or more severe (CIN2+) diagnosis. HRME with morphologic image analysis for detection of CIN Grade 3 or more severe diagnoses (CIN3+) was similarly sensitive (95.6% vs 96.2%, P = .81) and specific (56.6% vs 58.7%, P = .18) as colposcopy. HRME with morphologic image analysis for detection of CIN2+ was slightly less sensitive (91.7% vs 95.6%, P < .01) and specific (59.7% vs 63.4%, P = .02) than colposcopy. Images from 870 subjects were used to train a multi-task convolutional neural network-based algorithm and images from the remaining 616 were used to validate its performance. There were no significant differences in the sensitivity and specificity of HRME with neural network analysis vs colposcopy for detection of CIN2+ or CIN3+. Using a neural network-based algorithm, HRME has comparable sensitivity and specificity to colposcopy for detection of CIN2+. HRME could provide a low-cost, point-of-care alternative to colposcopy and biopsy in the prevention of cervical cancer.


Assuntos
Histeroscopia/instrumentação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Displasia do Colo do Útero/diagnóstico por imagem , Adulto , Idoso , Brasil , Colposcopia , Sistemas Computacionais , Feminino , Humanos , Microtecnologia , Pessoa de Meia-Idade , Redes Neurais de Computação , Sistemas Automatizados de Assistência Junto ao Leito , Estudos Prospectivos , Sensibilidade e Especificidade , Adulto Jovem
4.
Gastrointest Endosc ; 93(4): 831-838.e2, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32682812

RESUMO

BACKGROUND AND AIMS: High-resolution microendoscopy (HRME) is an optical biopsy technology that provides subcellular imaging of esophageal mucosa but requires expert interpretation of these histopathology-like images. We compared endoscopists with an automated software algorithm for detection of esophageal squamous cell neoplasia (ESCN) and evaluated the endoscopists' accuracy with and without input from the software algorithm. METHODS: Thirteen endoscopists (6 experts, 7 novices) were trained and tested on 218 post-hoc HRME images from 130 consecutive patients undergoing ESCN screening/surveillance. The automated software algorithm interpreted all images as neoplastic (high-grade dysplasia, ESCN) or non-neoplastic. All endoscopists provided their interpretation (neoplastic or non-neoplastic) and confidence level (high or low) without and with knowledge of the software overlay highlighting abnormal nuclei and software interpretation. The criterion standard was histopathology consensus diagnosis by 2 pathologists. RESULTS: The endoscopists had a higher mean sensitivity (84.3%, standard deviation [SD] 8.0% vs 76.3%, P = .004), lower specificity (75.0%, SD 5.2% vs 85.3%, P < .001) but no significant difference in accuracy (81.1%, SD 5.2% vs 79.4%, P = .26) of ESCN detection compared with the automated software algorithm. With knowledge of the software algorithm, the specificity of the endoscopists increased significantly (75.0% to 80.1%, P = .002) but not the sensitivity (84.3% to 84.8%, P = .75) or accuracy (81.1% to 83.1%, P = .13). The increase in specificity was among novices (P = .008) but not experts (P = .11). CONCLUSIONS: The software algorithm had lower sensitivity but higher specificity for ESCN detection than endoscopists. Using computer-assisted diagnosis, the endoscopists maintained high sensitivity while increasing their specificity and accuracy compared with their initial diagnosis. Automated HRME interpretation would facilitate widespread usage in resource-poor areas where this portable, low-cost technology is needed.


Assuntos
Esôfago , Neoplasias , Células Epiteliais , Esofagoscopia , Esôfago/diagnóstico por imagem , Humanos , Sensibilidade e Especificidade , Software
5.
Int J Exp Pathol ; 101(1-2): 45-54, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32436348

RESUMO

Oral cancer causes significant global mortality and has a five-year survival rate of around 64%. Poor prognosis results from late-stage diagnosis, highlighting an important need to develop better approaches to detect oral premalignant lesions (OPLs) and identify which OPLs are at highest risk of progression to oral squamous cell carcinoma (OSCC). An appropriate animal model that reflects the genetic, histologic, immunologic, molecular and gross visual features of human OSCC would aid in the development and evaluation of early detection and risk assessment strategies. Here, we present an experimental PIK3CA + 4NQO transgenic mouse model of oral carcinogenesis that combines the PIK3CA oncogene mutation with oral exposure to the chemical carcinogen 4NQO, an alternate experimental transgenic mouse model with PIK3CA as well as E6 and E7 mutations, and an existing wild-type mouse model based on oral exposure to 4NQO alone. We compare changes in dorsal and ventral tongue gross visual appearance, histologic features and molecular biomarker expression over a time course of carcinogenesis. Both transgenic models exhibit cytological and architectural features of dysplasia that mimic human disease and exhibit slightly increased staining for Ki-67, a cell proliferation marker. The PIK3CA + 4NQO model additionally exhibits consistent lymphocytic infiltration, presents with prominent dorsal and ventral tongue tumours, and develops cancer quickly relative to the other models. Thus, the PIK3CA + 4NQO model recapitulates the multistep genetic model of human oral carcinogenesis and host immune response in carcinogen-induced tongue cancer, making it a useful resource for future OSCC studies.


Assuntos
Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Neoplásica/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Mutação , Quinolonas , Carcinoma de Células Escamosas de Cabeça e Pescoço/induzido quimicamente , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Neoplasias da Língua/induzido quimicamente , Neoplasias da Língua/genética , 4-Nitroquinolina-1-Óxido , Animais , Proliferação de Células , Transformação Celular Neoplásica/patologia , Modelos Animais de Doenças , Progressão da Doença , Linfócitos/patologia , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Proteínas Oncogênicas Virais/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Fatores de Tempo , Neoplasias da Língua/patologia
6.
Gynecol Oncol ; 154(3): 558-564, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31288949

RESUMO

OBJECTIVE: Cervical cancer rates in the United States have declined since the 1940's, however, cervical cancer incidence remains elevated in medically-underserved areas, especially in the Rio Grande Valley (RGV) along the Texas-Mexico border. High-resolution microendoscopy (HRME) is a low-cost, in vivo imaging technique that can identify high-grade precancerous cervical lesions (CIN2+) at the point-of-care. The goal of this study was to evaluate the performance of HRME in medically-underserved areas in Texas, comparing results to a tertiary academic medical center. METHODS: HRME was evaluated in five different outpatient clinical settings, two in Houston and three in the RGV, with medical providers of varying skill and training. Colposcopy, followed by HRME imaging, was performed on eligible women. The sensitivity and specificity of traditional colposcopy and colposcopy followed by HRME to detect CIN2+ were compared and HRME image quality was evaluated. RESULTS: 174 women (227 cervical sites) were included in the final analysis, with 12% (11% of cervical sites) diagnosed with CIN2+ on histopathology. On a per-site basis, a colposcopic impression of low-grade precancer or greater had a sensitivity of 84% and a specificity of 45% to detect CIN2+. While there was no significant difference in sensitivity (76%, p = 0.62), the specificity when using HRME was significantly higher than that of traditional colposcopy (56%, p = 0.01). There was no significant difference in HRME image quality between clinical sites (p = 0.77) or medical providers (p = 0.33). CONCLUSIONS: HRME imaging increased the specificity for detecting CIN2+ when compared to traditional colposcopy. HRME image quality remained consistent across different clinical settings.


Assuntos
Colonoscopia/economia , Colonoscopia/métodos , Área Carente de Assistência Médica , Lesões Pré-Cancerosas/diagnóstico por imagem , Neoplasias do Colo do Útero/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Gradação de Tumores , Lesões Pré-Cancerosas/economia , Estudos Prospectivos , Sensibilidade e Especificidade , Texas , Estados Unidos , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/diagnóstico por imagem , Displasia do Colo do Útero/economia
7.
South Med J ; 111(12): 716-720, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30512122

RESUMO

OBJECTIVE: To compare the incidence of hypersensitivity reactions following copperhead envenomation treated with Fab antivenom (FabAV) or placebo. METHODS: Patients with copperhead snakebites received treatment and follow-up in a prospective, randomized, double-blind, placebo-controlled trial of FabAV or placebo. The treatment allocation ratio was 2:1 (FabAV:placebo). All of the included patients received at least one dose of study treatment. We reviewed all treatment-emergent adverse events (AEs) using a previously published scale to classify likely hypersensitivity reactions as mild, moderate, or severe. RESULTS: We enrolled 74 patients at 13 sites. Forty-five patients received FabAV, and 29 patients received placebo. Five FabAV patients and 4 placebo patients had moderate envenomations; the rest were mild. Twenty-five FabAV patients and 8 placebo patients had at least 1 AE. Mild skin reactions occurred in 11 (24%) FabAV patients (pruritis, urticaria, rash, ecchymosis, erythema) and 1 (3%) placebo patient (pruritis). Moderate gastrointestinal AEs occurred in 7 (16%) FabAV patients (nausea, vomiting, constipation, diarrhea, oral paresthesia) and in 2 (7%) placebo patients (nausea). Respiratory AEs occurred in 3 (7%) FabAV patients (dyspnea, pulmonary embolism, nasal congestion, sneezing) and no placebo patients. Hypotension occurred in 1 patient in each group. CONCLUSIONS: In a randomized controlled trial of FabAV for copperhead bites, the incidence of hypersensitivity reactions was low. Most reactions were mild skin reactions.


Assuntos
Agkistrodon , Antivenenos/efeitos adversos , Hipersensibilidade a Drogas/etiologia , Fragmentos Fab das Imunoglobulinas/efeitos adversos , Mordeduras de Serpentes/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antivenenos/uso terapêutico , Criança , Método Duplo-Cego , Hipersensibilidade a Drogas/epidemiologia , Feminino , Seguimentos , Humanos , Fragmentos Fab das Imunoglobulinas/uso terapêutico , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
9.
Gastroenterology ; 149(2): 321-329, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25980753

RESUMO

BACKGROUND & AIMS: Esophageal squamous cell neoplasia has a high mortality rate as a result of late detection. In high-risk regions such as China, screening is performed by Lugol's chromoendoscopy (LCE). LCE has low specificity, resulting in unnecessary tissue biopsy with a subsequent increase in procedure cost and risk. The purpose of this study was to evaluate the accuracy of a novel, low-cost, high-resolution microendoscope (HRME) as an adjunct to LCE. METHODS: In this prospective trial, 147 consecutive high-risk patients were enrolled from 2 US and 2 Chinese tertiary centers. Three expert and 4 novice endoscopists performed white-light endoscopy followed by LCE and HRME. All optical images were compared with the gold standard of histopathology. RESULTS: By using a per-biopsy analysis, the sensitivity of LCE vs LCE + HRME was 96% vs 91% (P = .0832), specificity was 48% vs 88% (P < .001), positive predictive value was 22% vs 45% (P < .0001), negative predictive value was 98% vs 98% (P = .3551), and overall accuracy was 57% vs 90% (P < .001), respectively. By using a per-patient analysis, the sensitivity of LCE vs LCE + HRME was 100% vs 95% (P = .16), specificity was 29% vs 79% (P < .001), positive predictive value was 32% vs 60%, 100% vs 98%, and accuracy was 47% vs 83% (P < .001). With the use of HRME, 136 biopsies (60%; 95% confidence interval, 53%-66%) could have been spared, and 55 patients (48%; 95% confidence interval, 38%-57%) could have been spared any biopsy. CONCLUSIONS: In this trial, HRME improved the accuracy of LCE for esophageal squamous cell neoplasia screening and surveillance. HRME may be a cost-effective optical biopsy adjunct to LCE, potentially reducing unnecessary biopsies and facilitating real-time decision making in globally underserved regions. ClinicalTrials.gov, NCT 01384708.


Assuntos
Detecção Precoce de Câncer/métodos , Neoplasias Esofágicas/diagnóstico , Esofagoscopia/métodos , Neoplasias de Células Escamosas/diagnóstico , Imagem Óptica/métodos , Lesões Pré-Cancerosas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , China , Neoplasias Esofágicas/patologia , Feminino , Humanos , Iodetos , Masculino , Pessoa de Meia-Idade , Neoplasias de Células Escamosas/patologia , Lesões Pré-Cancerosas/patologia , Estudos Prospectivos , Sensibilidade e Especificidade , Estados Unidos
10.
Gastrointest Endosc ; 84(5): 834-841, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27036635

RESUMO

BACKGROUND AND AIMS: In recent years high-resolution microendoscopy (HRME) has shown potential to improve screening for esophageal squamous cell neoplasia. Furthering its utility in a clinical setting, especially in lower-resource settings, could be accomplished by reducing the size and cost of the system as well as incorporating the ability of real-time, objective feedback. This article describes a tablet-interfaced HRME with fully automated, real-time image analysis. METHODS: The performance of the tablet-interfaced HRME was assessed by acquiring images from the oral mucosa in a normal volunteer. An automated, real-time analysis algorithm was developed and evaluated using training, test, and validation images from a previous in vivo study of 177 patients referred for screening or surveillance endoscopy in China. The algorithm was then implemented in a tablet HRME that was used to obtain and analyze images from esophageal tissue in 3 patients. Images were displayed alongside the probability that the imaged region was neoplastic. RESULTS: The tablet-interfaced HRME demonstrated comparable imaging performance at a lower cost compared with first-generation laptop-interfaced HRME systems. In a post-hoc quantitative analysis, the algorithm identified neoplasia with a sensitivity and specificity of 95% and 91%, respectively, in the validation set compared with 84% and 95% achieved in the original study. CONCLUSIONS: The tablet-based HRME is a low-cost tool that provides quantitative diagnostic information to the endoscopist in real time. This could be especially beneficial in lower-resource settings for operators with less experience interpreting HRME images.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Computadores de Mão , Neoplasias Esofágicas/diagnóstico por imagem , Esofagoscopia/instrumentação , Interpretação de Imagem Assistida por Computador , Microscopia Intravital/instrumentação , Algoritmos , Humanos , Aplicativos Móveis , Sensibilidade e Especificidade
11.
Circ Res ; 114(8): 1302-10, 2014 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-24565698

RESUMO

RATIONALE: Although accumulating data support the efficacy of intramyocardial cell-based therapy to improve left ventricular (LV) function in patients with chronic ischemic cardiomyopathy undergoing CABG, the underlying mechanism and impact of cell injection site remain controversial. Mesenchymal stem cells (MSCs) improve LV structure and function through several effects including reducing fibrosis, neoangiogenesis, and neomyogenesis. OBJECTIVE: To test the hypothesis that the impact on cardiac structure and function after intramyocardial injections of autologous MSCs results from a concordance of prorecovery phenotypic effects. METHODS AND RESULTS: Six patients were injected with autologous MSCs into akinetic/hypokinetic myocardial territories not receiving bypass graft for clinical reasons. MRI was used to measure scar, perfusion, wall thickness, and contractility at baseline, at 3, 6, and 18 months and to compare structural and functional recovery in regions that received MSC injections alone, revascularization alone, or neither. A composite score of MRI variables was used to assess concordance of antifibrotic effects, perfusion, and contraction at different regions. After 18 months, subjects receiving MSCs exhibited increased LV ejection fraction (+9.4 ± 1.7%, P=0.0002) and decreased scar mass (-47.5 ± 8.1%; P<0.0001) compared with baseline. MSC-injected segments had concordant reduction in scar size, perfusion, and contractile improvement (concordant score: 2.93 ± 0.07), whereas revascularized (0.5 ± 0.21) and nontreated segments (-0.07 ± 0.34) demonstrated nonconcordant changes (P<0.0001 versus injected segments). CONCLUSIONS: Intramyocardial injection of autologous MSCs into akinetic yet nonrevascularized segments produces comprehensive regional functional restitution, which in turn drives improvement in global LV function. These findings, although inconclusive because of lack of placebo group, have important therapeutic and mechanistic hypothesis-generating implications. CLINICAL TRIAL REGISTRATION URL: http://clinicaltrials.gov/show/NCT00587990. Unique identifier: NCT00587990.


Assuntos
Cardiomiopatias/terapia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Ponte de Artéria Coronária , Transplante de Células-Tronco Mesenquimais/métodos , Isquemia Miocárdica/terapia , Miocárdio/patologia , Disfunção Ventricular Esquerda/terapia , Cicatriz/patologia , Cicatriz/terapia , Fibrose/patologia , Fibrose/terapia , Seguimentos , Humanos , Injeções , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fenótipo , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento
12.
Clin Gastroenterol Hepatol ; 13(2): 272-279.e2, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25066838

RESUMO

BACKGROUND & AIMS: High-resolution microendoscopy is an optical imaging technique with the potential to improve the accuracy of endoscopic screening for esophageal squamous neoplasia. Although these microscopic images can be interpreted readily by trained personnel, quantitative image analysis software could facilitate the use of this technology in low-resource settings. In this study, we developed and evaluated quantitative image analysis criteria for the evaluation of neoplastic and non-neoplastic squamous esophageal mucosa. METHODS: We performed an image analysis of 177 patients undergoing standard upper endoscopy for screening or surveillance of esophageal squamous neoplasia, using high-resolution microendoscopy, at 2 hospitals in China and at 1 hospital in the United States from May 2010 to October 2012. Biopsy specimens were collected from imaged sites (n = 375), and a consensus diagnosis was provided by 2 expert gastrointestinal pathologists and used as the standard. RESULTS: Quantitative information from the high-resolution images was used to develop an algorithm to identify high-grade squamous dysplasia or invasive squamous cell cancer, based on histopathology findings. Optimal performance was obtained using the mean nuclear area as the basis for classification, resulting in sensitivities and specificities of 93% and 92% in the training set, 87% and 97% in the test set, and 84% and 95% in an independent validation set, respectively. CONCLUSIONS: High-resolution microendoscopy with quantitative image analysis can aid in the identification of esophageal squamous neoplasia. Use of software-based image guides may overcome issues of training and expertise in low-resource settings, allowing for widespread use of these optical biopsy technologies.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/patologia , Esofagoscopia/métodos , Processamento de Imagem Assistida por Computador/métodos , Biópsia , China , Carcinoma de Células Escamosas do Esôfago , Hospitais , Humanos , Programas de Rastreamento/métodos , Estados Unidos
13.
Orig Life Evol Biosph ; 45(4): 469-77, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26113154

RESUMO

Approximately 60% of all stars in the solar neighbourhood (up to 80% in our Milky Way) are members of binary or multiple star systems. This fact led to the speculations that many more planets may exist in binary systems than are currently known. To estimate the habitability of exoplanetary systems, we have to define the so-called habitable zone (HZ). The HZ is defined as a region around a star where a planet would receive enough radiation to maintain liquid water on its surface and to be able to build a stable atmosphere. We search for new dynamical configurations-where planets may stay in stable orbits-to increase the probability to find a planet like the Earth.


Assuntos
Exobiologia , Meio Ambiente Extraterreno , Planetas , Astros Celestes , Modelos Teóricos
14.
JAMA ; 311(1): 62-73, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24247587

RESUMO

IMPORTANCE: Whether culture-expanded mesenchymal stem cells or whole bone marrow mononuclear cells are safe and effective in chronic ischemic cardiomyopathy is controversial. OBJECTIVE: To demonstrate the safety of transendocardial stem cell injection with autologous mesenchymal stem cells (MSCs) and bone marrow mononuclear cells (BMCs) in patients with ischemic cardiomyopathy. DESIGN, SETTING, AND PATIENTS: A phase 1 and 2 randomized, blinded, placebo-controlled study involving 65 patients with ischemic cardiomyopathy and left ventricular (LV) ejection fraction less than 50% (September 1, 2009-July 12, 2013). The study compared injection of MSCs (n=19) with placebo (n = 11) and BMCs (n = 19) with placebo (n = 10), with 1 year of follow-up. INTERVENTIONS: Injections in 10 LV sites with an infusion catheter. MAIN OUTCOMES AND MEASURES: Treatment-emergent 30-day serious adverse event rate defined as a composite of death, myocardial infarction, stroke, hospitalization for worsening heart failure, perforation, tamponade, or sustained ventricular arrhythmias. RESULTS: No patient had a treatment-emergent serious adverse events at day 30. The 1-year incidence of serious adverse events was 31.6% (95% CI, 12.6% to 56.6%) for MSCs, 31.6% (95% CI, 12.6%-56.6%) for BMCs, and 38.1% (95% CI, 18.1%-61.6%) for placebo. Over 1 year, the Minnesota Living With Heart Failure score improved with MSCs (-6.3; 95% CI, -15.0 to 2.4; repeated measures of variance, P=.02) and with BMCs (-8.2; 95% CI, -17.4 to 0.97; P=.005) but not with placebo (0.4; 95% CI, -9.45 to 10.25; P=.38). The 6-minute walk distance increased with MSCs only (repeated measures model, P = .03). Infarct size as a percentage of LV mass was reduced by MSCs (-18.9%; 95% CI, -30.4 to -7.4; within-group, P = .004) but not by BMCs (-7.0%; 95% CI, -15.7% to 1.7%; within-group, P = .11) or placebo (-5.2%; 95% CI, -16.8% to 6.5%; within-group, P = .36). Regional myocardial function as peak Eulerian circumferential strain at the site of injection improved with MSCs (-4.9; 95% CI, -13.3 to 3.5; within-group repeated measures, P = .03) but not BMCs (-2.1; 95% CI, -5.5 to 1.3; P = .21) or placebo (-0.03; 95% CI, -1.9 to 1.9; P = .14). Left ventricular chamber volume and ejection fraction did not change. CONCLUSIONS AND RELEVANCE: Transendocardial stem cell injection with MSCs or BMCs appeared to be safe for patients with chronic ischemic cardiomyopathy and LV dysfunction. Although the sample size and multiple comparisons preclude a definitive statement about safety and clinical effect, these results provide the basis for larger studies to provide definitive evidence about safety and to assess efficacy of this new therapeutic approach. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00768066.


Assuntos
Transplante de Medula Óssea/métodos , Transplante de Células-Tronco Mesenquimais/métodos , Isquemia Miocárdica/terapia , Idoso , Transplante de Medula Óssea/efeitos adversos , Cardiomiopatias , Progressão da Doença , Método Duplo-Cego , Feminino , Hospitalização , Humanos , Masculino , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Pessoa de Meia-Idade , Infarto do Miocárdio , Acidente Vascular Cerebral , Análise de Sobrevida , Transplante Autólogo , Resultado do Tratamento , Disfunção Ventricular Esquerda/terapia
15.
J Biomed Opt ; 29(5): 050501, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38774711

RESUMO

Significance: Fiber-optic microendoscopy is a promising approach to noninvasively visualize epithelial nuclear morphometry for early cancer and precancer detection. However, the broader clinical application of this approach is limited by a lack of topical contrast agents available for in vivo use. Aim: The aim of this study was to evaluate the ability to image nuclear morphometry in vivo with a novel fiber-optic microendoscope used together with topical application of methylene blue (MB), a dye with FDA approval for use in chromoendoscopy in the gastrointestinal tract. Approach: The low-cost, high-resolution microendoscope implements scanning darkfield imaging without complex optomechanical components by leveraging programmable illumination and the rolling shutter of the image sensor. We validate the integration of our system and MB staining for visualizing epithelial cell nuclei by performing ex vivo imaging on fresh animal specimens and in vivo imaging on healthy volunteers. Results: The results indicate that scanning darkfield imaging significantly reduces specular reflection and resolves epithelial nuclei with enhanced image contrast and spatial resolution compared to non-scanning widefield imaging. The image quality of darkfield images with MB staining is comparable to that of fluorescence images with proflavine staining. Conclusions: Our approach enables real-time microscopic evaluation of nuclear patterns and has the potential to be a powerful noninvasive tool for early cancer detection.


Assuntos
Azul de Metileno , Azul de Metileno/química , Animais , Humanos , Núcleo Celular , Tecnologia de Fibra Óptica/instrumentação , Desenho de Equipamento , Endoscopia/métodos , Endoscopia/instrumentação , Administração Tópica
16.
Bioengineering (Basel) ; 11(6)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38927792

RESUMO

Esophageal carcinoma is the sixth-leading cause of cancer death worldwide. A precursor to esophageal adenocarcinoma (EAC) is Barrett's Esophagus (BE). Early-stage diagnosis and treatment of esophageal neoplasia (Barrett's with high-grade dysplasia/intramucosal cancer) increase the five-year survival rate from 10% to 98%. BE is a global challenge; however, current endoscopes for early BE detection are costly and require extensive infrastructure for patient examination and sedation. We describe the design and evaluation of the first prototype of ScanCap, a high-resolution optical endoscopy system with a reusable, low-cost tethered capsule, designed to provide high-definition, blue-green illumination imaging for the early detection of BE in unsedated patients. The tethered capsule (12.8 mm diameter, 35.5 mm length) contains a color camera and rotating mirror and is designed to be swallowed; images are collected as the capsule is retracted manually via the tether. The tether provides electrical power and illumination at wavelengths of 415 nm and 565 nm and transmits data from the camera to a tablet. The ScanCap prototype capsule was used to image the oral mucosa in normal volunteers and ex vivo esophageal resections; images were compared to those obtained using an Olympus CV-180 endoscope. Images of superficial capillaries in intact oral mucosa were clearly visible in ScanCap images. Diagnostically relevant features of BE, including irregular Z-lines, distorted mucosa, and dilated vasculature, were clearly visible in ScanCap images of ex vivo esophageal specimens.

17.
IEEE Trans Biomed Eng ; PP2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38507389

RESUMO

OBJECTIVE: Early detection and treatment of cervical precancers can prevent disease progression. However, in low-resource communities with a high incidence of cervical cancer, high equipment costs and a shortage of specialists hinder preventative strategies. This manuscript presents a low-cost multiscale in vivo optical imaging system coupled with a computer-aided diagnostic system that could enable accurate, real-time diagnosis of high-grade cervical precancers. METHODS: The system combines portable colposcopy and high-resolution endomicroscopy (HRME) to acquire spatially registered widefield and microscopy videos. A multiscale imaging fusion network (MSFN) was developed to identify cervical intraepithelial neoplasia grade 2 or more severe (CIN 2+). The MSFN automatically identifies and segments the ectocervix and lesions from colposcopy images, extracts nuclear morphology features from HRME videos, and integrates the colposcopy and HRME information. RESULTS: With a threshold value set to achieve sensitivity equal to clinical impression (0.98 [p = 1.0]), the MSFN achieved a significantly higher specificity than clinical impression (0.75 vs. 0.43, p = 0.000006). CONCLUSION: Our findings show that multiscale optical imaging of the cervix allows the highly sensitive and specific detection of high-grade precancers. SIGNIFICANCE: The multiscale imaging system and MSFN could facilitate the accurate, real-time diagnosis of cervical precancers in low-resource settings.

18.
Clin Transl Gastroenterol ; 14(2): e00558, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36729506

RESUMO

INTRODUCTION: In the United States, the effectiveness of anal cancer screening programs has been limited by a lack of trained professionals proficient in high-resolution anoscopy (HRA) and a high patient lost-to-follow-up rate between diagnosis and treatment. Simplifying anal intraepithelial neoplasia grade 2 or more severe (AIN 2+) detection could radically improve the access and efficiency of anal cancer prevention. Novel optical imaging providing point-of-care diagnoses could substantially improve existing HRA and histology-based diagnosis. This work aims to demonstrate the potential of high-resolution microendoscopy (HRME) coupled with a novel machine learning algorithm for the automated, in vivo diagnosis of anal precancer. METHODS: The HRME, a fiber-optic fluorescence microscope, was used to capture real-time images of anal squamous epithelial nuclei. Nuclear staining is achieved using 0.01% wt/vol proflavine, a topical contrast agent. HRME images were analyzed by a multitask deep learning network (MTN) that computed the probability of AIN 2+ for each HRME image. RESULTS: The study accrued data from 77 people living with HIV. The MTN achieved an area under the receiver operating curve of 0.84 for detection of AIN 2+. At the AIN 2+ probability cutoff of 0.212, the MTN achieved comparable performance to expert HRA impression with a sensitivity of 0.92 ( P = 0.68) and specificity of 0.60 ( P = 0.48) when using histopathology as the gold standard. DISCUSSION: When used in combination with HRA, this system could facilitate more selective biopsies and promote same-day AIN2+ treatment options by enabling real-time diagnosis.


Assuntos
Neoplasias do Ânus , Infecções por HIV , Humanos , Papillomavirus Humano , Canal Anal , Neoplasias do Ânus/complicações , Neoplasias do Ânus/diagnóstico , Neoplasias do Ânus/patologia , Biópsia , Infecções por HIV/complicações , Infecções por HIV/patologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-38406798

RESUMO

Cancer continues to affect underserved populations disproportionately. Novel optical imaging technologies, which can provide rapid, non-invasive, and accurate cancer detection at the point of care, have great potential to improve global cancer care. This article reviews the recent technical innovations and clinical translation of low-cost optical imaging technologies, highlighting the advances in both hardware and software, especially the integration of artificial intelligence, to improve in vivo cancer detection in low-resource settings. Additionally, this article provides an overview of existing challenges and future perspectives of adapting optical imaging technologies into clinical practice, which can potentially contribute to novel insights and programs that effectively improve cancer detection in low-resource settings.

20.
PLOS Glob Public Health ; 3(8): e0002262, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37552665

RESUMO

Neonatal jaundice is an important cause of morbidity and mortality worldwide, and neonates born in low and middle-income countries bear a disproportionate burden. We previously developed a low-cost, point-of-care system to measure total serum bilirubin (TSB) in neonates. This device was effective at detecting and monitoring jaundice; however, the disposable strips were difficult to produce at scale. Here, we report a new lateral flow cassette design, called BiliDx, that was produced at scale using traditional manufacturing techniques. We evaluated the performance of BiliDx at sites in Nigeria and Malawi. The lateral flow strip consists of plasma separation membranes, nitrocellulose, and a plastic cassette. We evaluated the performance of the strips and reader at two hospitals located in Nigeria and Malawi compared to reference standard TSB. We also assessed performance for samples with high direct bilirubin (DB) and high hematocrit (HCT). We collected 1,144 samples from 758 neonates (TSB ranged from 0.2 to 45.9 mg/dL). The mean bias of BiliDx measurements in the validation set was +0.75 mg/dL, and 95% limits of agreement were -2.57 to 4.07 mg/dL. The mean bias and limits of agreement were comparable for samples with HCT < 60% and HCT ≥ 60%, and for samples with low and intermediate DB levels; the samples with high DB levels had wider 95% limits of agreement (-4.50 to +3.03 mg/dL). Error grid analysis shows that 96.9% of samples measured with BiliDx would have resulted in the same clinical decision as the reference standard. This performance is comparable to previous results that used a handmade two-dimensional strip. Additionally, error grid analysis shows that all 20 samples with high DB levels would have resulted in the same clinical decision as the reference standard. This evaluation supports the use of BiliDx lateral flow cassettes to provide accurate point-of-care measurements in low-resource settings.

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