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1.
Lab Chip ; 23(3): 451-465, 2023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36562325

RESUMEN

Cervical cancer is a leading cause of cancer death for women in low-resource settings. The World Health Organization recommends that cervical cancer screening programs incorporate HPV DNA testing, but available tests are expensive, require laboratory infrastructure, and cannot be performed at the point-of-care. We developed a two-dimensional paper network (2DPN), hybrid-capture, signal amplification assay and a point-of-care sample preparation protocol to detect high-risk HPV DNA from exfoliated cervical cells within an hour. The test does not require expensive equipment and has an estimated cost of <$3 per test without the need for batching. We evaluated performance of the paper HPV DNA assay with short synthetic and genomic HPV DNA targets, HPV positive and negative cellular samples, and two sets of clinical samples. The first set of clinical samples consisted of 16 biobanked, provider-collected cervical samples from a study in El Salvador previously tested with careHPV and subsequently tested in a controlled laboratory environment. The paper HPV DNA test correctly identified eight of eight HPV-negative clinical samples and seven of eight HPV-positive clinical samples. We then performed a field evaluation of the paper HPV DNA test in a hospital laboratory in Mozambique. Cellular controls generated expected results throughout field testing with fully lyophilized sample preparation and 2DPN reagents. When evaluated with 16 residual self-collected cervicovaginal samples previously tested by the GeneXpert HPV assay ("Xpert"), the accuracy of the HPV DNA paper test in the field was reduced compared to testing in the controlled laboratory environment, with positive results obtained for all eight HPV-positive samples as well as seven of eight HPV-negative samples. Further evaluation showed reduction in performance was likely due in part to increased concentration of exfoliated cells in the self-collected clinical samples from Mozambique compared with provider-collected samples from El Salvador. Finally, a formal usability assessment was conducted with users in El Salvador and Mozambique; the assay was rated as acceptable to perform after minimal training. With additional optimization for higher cell concentrations and inclusion of an internal cellular control, the paper HPV DNA assay offers promise as a low-cost, point-of-care cervical cancer screening test in low-resource settings.


Asunto(s)
Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/prevención & control , Infecciones por Papillomavirus/diagnóstico , Detección Precoz del Cáncer/métodos , Interfaz Usuario-Computador , Papillomaviridae/genética , ADN
2.
Comput Med Imaging Graph ; 97: 102052, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35299096

RESUMEN

Cervical cancer is a public health emergency in low- and middle-income countries where resource limitations hamper standard-of-care prevention strategies. The high-resolution endomicroscope (HRME) is a low-cost, point-of-care device with which care providers can image the nuclear morphology of cervical lesions. Here, we propose a deep learning framework to diagnose cervical intraepithelial neoplasia grade 2 or more severe from HRME images. The proposed multi-task convolutional neural network uses nuclear segmentation to learn a diagnostically relevant representation. Nuclear segmentation was trained via proxy labels to circumvent the need for expensive, manually annotated nuclear masks. A dataset of images from over 1600 patients was used to train, validate, and test our algorithm; data from 20% of patients were reserved for testing. An external evaluation set with images from 508 patients was used to further validate our findings. The proposed method consistently outperformed other state-of-the art architectures achieving a test per patient area under the receiver operating characteristic curve (AUC-ROC) of 0.87. Performance was comparable to expert colposcopy with a test sensitivity and specificity of 0.94 (p = 0.3) and 0.58 (p = 1.0), respectively. Patients with recurrent human papillomavirus (HPV) infections are at a higher risk of developing cervical cancer. Thus, we sought to incorporate HPV DNA test results as a feature to inform prediction. We found that incorporating patient HPV status improved test specificity to 0.71 at a sensitivity of 0.94.


Asunto(s)
Infecciones por Papillomavirus , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Colposcopía/métodos , Detección Precoz del Cáncer/métodos , Femenino , Humanos , Redes Neurales de la Computación , Infecciones por Papillomavirus/diagnóstico por imagen , Embarazo , Sensibilidad y Especificidad , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/patología , Displasia del Cuello del Útero/diagnóstico por imagen , Displasia del Cuello del Útero/patología
3.
JCO Glob Oncol ; 8: e2100214, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34985911

RESUMEN

In 2018, there were approximately 570,000 new cases of cervical cancer worldwide. More than 85% of cases occurred in low- and middle-income countries (LMICs), primarily because of poor access to screening and a limited number of medical providers trained to diagnose and treat cervical precancerous lesions. Our objective was to provide locally arranged, hands-on training courses for medical providers in LMICs to learn to perform cervical cancer screening, diagnosis, and treatment procedures. The courses included didactic lectures and hands-on training stations using low-cost simulation models developed by bioengineers and students at Rice University in Houston, TX, United States, and the Malawi Polytechnic in Blantyre, Malawi. The hands-on training stations included visual inspection with acetic acid (VIA), colposcopy, cervical biopsy, endocervical curettage, loop electrosurgical excision procedure (LEEP), and thermal ablation. Provider pre- and postcourse confidence levels in performing the procedures were evaluated. From February 2017 to January 2020, we arranged 15 hands-on training courses in seven cities across six countries (El Salvador, Mozambique, Trinidad and Tobago, Lesotho, Malawi, and Nepal). Overall, there were 506 participants. The average number of participants per course was 38 (range 19-92). The participants included doctors, nurses, and midwives. The course duration varied from 1 to 3 days. Increased confidence in performing VIA, colposcopy and cervical biopsy, ablation, and LEEP was reported by 69%, 71%, 61%, and 76% of participants, respectively. Our findings suggest that locally arranged, hands-on cervical cancer prevention training courses in LMICs can improve provider confidence in performing cervical cancer screening, diagnosis, and treatment procedures. These courses are part of a larger strategy to build local capacity for delivering and improving cervical cancer prevention services in LMICs.


Asunto(s)
Neoplasias del Cuello Uterino , Ácido Acético , Cuello del Útero , Colposcopía , Países en Desarrollo , Detección Precoz del Cáncer , Femenino , Humanos , Embarazo , Estados Unidos , Neoplasias del Cuello Uterino/prevención & control , Neoplasias del Cuello Uterino/terapia
5.
Int J Cancer ; 148(10): 2571-2578, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33368249

RESUMEN

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.

6.
IEEE J Transl Eng Health Med ; 8: 4300210, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32190430

RESUMEN

Cervical cancer disproportionally affects women in low- and middle-income countries, in part due to the difficulty of implementing existing cervical cancer screening and diagnostic technologies in low-resource settings. Single-board computers offer a low-cost alternative to provide computational support for automated point-of-care technologies. Here we demonstrate two new devices for cervical cancer prevention that use a single-board computer: 1) a low-cost imaging system for real-time detection of cervical precancer and 2) a low-cost reader for real-time interpretation of lateral flow-based molecular tests to detect cervical cancer biomarkers. Using a Raspberry Pi computer to provide real-time image collection and processing, we developed: 1) a low-cost, portable high-resolution microendoscope system (PiHRME); and 2) a low-cost automatic lateral flow test reader (PiReader). The PiHRME acquired high-resolution ([Formula: see text]) images of the cervix at half the cost of existing high-resolution microendoscope systems; image analysis algorithms based on convolutional neural networks were implemented to provide real-time image interpretation. The PiReader acquired and analyzed images of a point-of-care human papillomavirus (HPV) serology test with the same contrast and accuracy as a standard flatbed high-resolution scanner coupled to a laptop computer, for less than one-fifth of the cost. Raspberry Pi single-board computers provide a low-cost means to implement point-of-care tools with automatic image analysis. This work demonstrates the promise of single-board computers to develop and translate low-cost, point-of-care technologies for use in low-resource settings.

7.
Biomed Opt Express ; 11(1): 269-280, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32010516

RESUMEN

Cervical cancer incidence and mortality rates remain high in medically underserved areas. In this study, we present a low-cost (<$5,000), portable and user-friendly confocal microendoscope, and we report on its clinical use to image precancerous lesions in the cervix. The confocal microendoscope employs digital apertures on a digital light projector and a CMOS sensor to implement line-scanning confocal imaging. Leveraging its versatile programmability, we describe an automated aperture alignment algorithm to ensure clinical ease-of-use and to facilitate technology dissemination in low-resource settings. Imaging performance is then evaluated in ex vivo and in vivo pilot studies; results demonstrate that the confocal microendoscope can enhance visualization of nuclear morphology, contributing to significantly improved recognition of clinically important features for detection of cervical precancer.

8.
Gynecol Oncol ; 154(3): 558-564, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31288949

RESUMEN

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.


Asunto(s)
Colonoscopía/economía , Colonoscopía/métodos , Área sin Atención Médica , Lesiones Precancerosas/diagnóstico por imagen , Neoplasias del Cuello Uterino/diagnóstico por imagen , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Clasificación del Tumor , Lesiones Precancerosas/economía , Estudios Prospectivos , Sensibilidad y Especificidad , Texas , Estados Unidos , Neoplasias del Cuello Uterino/patología , Displasia del Cuello del Útero/diagnóstico por imagen , Displasia del Cuello del Útero/economía
9.
Obstet Gynecol ; 133(3): 559-567, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30741811

RESUMEN

BACKGROUND: Cervical cancer remains one of the leading causes of cancer for women in medically underserved areas. This is in part due to a lack of trained clinicians to provide the necessary diagnosis and treatment of precancerous lesions to prevent cervical cancer. Increasing medical provider knowledge and skills is important for the early detection and prevention of cervical precancer and cancer in medically underserved areas of the United States and globally. METHOD: LUCIA is a low-cost, universal cervical cancer instructional apparatus that can be used to teach and practice a variety of essential skills for cervical cancer screening, diagnosis, and treatment, including: visual inspection with acetic acid, Pap and human papillomavirus DNA specimen collection, colposcopy, endocervical curettage, cervical biopsy, cryotherapy, and loop electrosurgical excision procedure. EXPERIENCE: LUCIA was used to provide hands-on training in six courses held in Texas (n=3), El Salvador (n=1), and Mozambique, Africa (n=2). Standardized provider evaluations were administered at three of these courses and resulted in mean scores of 4.12/5 for usefulness, 4.46/5 for skill improvement, and 4.43/5 for ease of skill evaluation. CONCLUSION: LUCIA provides dynamic, real-time feedback that allows trainees to learn and practice important skills related to cervical cancer prevention while simulating a patient exam.


Asunto(s)
Países en Desarrollo , Detección Precoz del Cáncer , Educación Médica/métodos , Entrenamiento Simulado/métodos , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/prevención & control , Biopsia , Cuello del Útero/patología , Competencia Clínica , Colposcopía/educación , Detección Precoz del Cáncer/métodos , El Salvador , Diseño de Equipo , Femenino , Humanos , Mozambique , Prueba de Papanicolaou , Entrenamiento Simulado/economía , Texas
10.
Photochem Photobiol ; 94(6): 1308-1313, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29981148

RESUMEN

Proflavine is an acridine dye used with high-resolution microendoscopy for in vivo diagnostic evaluation of cervical epithelial cells. However, there are concerns that even short-term exposure of cervical tissue to dilute proflavine may increase cervical cancer risk. We performed a retrospective analysis of women referred for colposcopy to Barretos Cancer Hospital comparing the risk of cervical disease progression in those whose cervical tissue was (n = 232) or was not exposed (n = 160) to proflavine. Patients in both groups underwent treatment and follow-up based on histopathologic results and per the local standards of care. Progression of disease was evaluated by comparing histopathology from the initial visit to the worst subsequent histopathology result from all follow-up visits. Mean duration of follow-up was 18.7 and 20.1 months for the proflavine-exposed and controls groups, respectively. There were no significant differences in disease progression from normal/CIN1 to CIN2/3 or from any initial diagnosis to invasive cancer between the proflavine exposed and control groups overall. Risks of cervical dysplasia progression observed in this study are in agreement with those of the natural history of cervical cancer. Our results suggest that cervical exposure to dilute proflavine does not increase the risk of cervical precancer and cancer.


Asunto(s)
Cuello del Útero/diagnóstico por imagen , Colposcopía/métodos , Medios de Contraste/administración & dosificación , Proflavina/administración & dosificación , Displasia del Cuello del Útero/diagnóstico por imagen , Neoplasias del Cuello Uterino/diagnóstico por imagen , Adulto , Cuello del Útero/metabolismo , Cuello del Útero/patología , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Riesgo , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/patología , Displasia del Cuello del Útero/metabolismo , Displasia del Cuello del Útero/patología
11.
Rheumatol Int ; 35(8): 1423-30, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25636236

RESUMEN

Patients in randomized clinical trials have to adapt themselves to a restricted language to capture the necessary information to determine the safety and efficacy of a new treatment. The aim of this study was to explore the experience of patients with rheumatoid arthritis after completing their participation in a biologic therapy randomized clinical trial for a period of 3 years. A qualitative approach was used. The information was collected using 15 semi-structured interviews of patients with rheumatoid arthritis. Data collection was guided by the emergent analysis until no more relevant variations in the categories were found. The data were analysed using the grounded theory method. The objective of the patients when entering the study was to improve their quality of life by initiating the treatment. However, the experience changed the significance of the illness as they acquired skills and practical knowledge related to the management of their disease. The category "Interactional Empowerment" emerged as core category, as it represented the participative experience in a clinical trial. The process integrates the follow categories: "weight of systematisation", "working together", and the significance of the experience: "the duties". Simultaneously these categories evolved. The clinical trial monitoring activities enabled patients to engage in a reflexive-interpretative mechanism that transformed the emotional and symbolic significance of their disease and improved the empowerment of the patient. A better communicative strategy with the health professionals, the relatives of the patients, and the community was also achieved.


Asunto(s)
Artritis Reumatoide/psicología , Conocimientos, Actitudes y Práctica en Salud , Participación del Paciente/psicología , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto/psicología , Adulto , Anciano , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Productos Biológicos/uso terapéutico , Estudios de Cohortes , Conducta Cooperativa , Femenino , Teoría Fundamentada , Humanos , Masculino , Persona de Mediana Edad , Motivación , Educación del Paciente como Asunto , Relaciones Médico-Paciente , Investigación Cualitativa , Adulto Joven
12.
Obes Res Clin Pract ; 8(1): e98-105, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24548582

RESUMEN

BACKGROUND: We aimed to identify risk factors for childhood overweight and obesity and the accuracy of caregivers'€™ perceptions of their child's nutritional status in the Magallanes region, Patagonia, Chile. METHODS: Heights and weights of children attending day care centers and elementary schools were collected and caregivers completed questionnaires regarding their child's health and behavior. The child's nutritional status was diagnosed using the 2006 WHO Child Growth Standards (for children under age 6) and the CDC 2000 Growth Charts (for children age 6 and older). Logistic regression was used to evaluate factors related to childhood overweight/obesity and weight underestimation by caregivers of overweight or obese children. RESULTS: Of the 795 children included in the study, 247 (31.1%) were overweight and 223 (28.1%) were obese. Risk factors for overweight/obesity included younger age and being perceived to eat more than normal by the caregiver. Caregivers were less likely to underestimate their child's weight if the child was older or if the caregiver believed the child ate more than a normal amount. CONCLUSIONS: There is a high prevalence of overweight and obesity among children in Magallanes and the majority of caregivers underestimate the extent of the problem in their children.


Asunto(s)
Cuidadores , Ingestión de Energía , Conducta Alimentaria , Conocimientos, Actitudes y Práctica en Salud , Estado Nutricional , Obesidad Infantil , Percepción del Peso , Factores de Edad , Niño , Preescolar , Chile/epidemiología , Familia , Femenino , Crecimiento , Humanos , Lactante , Modelos Logísticos , Masculino , Sobrepeso/epidemiología , Obesidad Infantil/epidemiología , Obesidad Infantil/etiología , Factores de Riesgo , Encuestas y Cuestionarios
13.
J Vis Exp ; (67): e3848, 2012 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-23023035

RESUMEN

Multiphoton microscopy of intrinsic fluorescence and second harmonic generation (SHG) of whole mouse organs is made possible by optically clearing the organ before imaging.(1,2) However, for organs that contain fluorescent proteins such as GFP and YFP, optical clearing protocols that use methanol dehydration and clear using benzyl alcohol:benzyl benzoate (BABB) while unprotected from light(3) do not preserve the fluorescent signal. The protocol presented here is a novel way in which to perform whole organ optical clearing on mouse brain while preserving the fluorescence signal of YFP expressed in neurons. Altering the optical clearing protocol such that the organ is dehydrated using an ethanol graded series has been found to reduce the damage to the fluorescent proteins and preserve their fluorescent signal for multiphoton imaging.(4) Using an optimized method of optical clearing with ethanol-based dehydration and clearing by BABB while shielded from light, we show high-resolution multiphoton images of yellow fluorescent protein (YFP) expression in the neurons of a mouse brain more than 2 mm beneath the tissue surface.


Asunto(s)
Proteínas Bacterianas/biosíntesis , Encéfalo/ultraestructura , Proteínas Luminiscentes/biosíntesis , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Animales , Proteínas Bacterianas/química , Benzoatos/química , Alcohol Bencilo/química , Encéfalo/metabolismo , Etanol/química , Proteínas Luminiscentes/química , Ratones , Neocórtex/ultraestructura , Neuronas/ultraestructura , Perfusión , Células Piramidales/ultraestructura
14.
J Biomed Opt ; 15(3): 036017, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20615019

RESUMEN

Typical imaging depths with multiphoton microscopy (MPM) are limited to less than 300 mum in many tissues due to light scattering. Optical clearing significantly reduces light scattering by replacing water in the organ tissue with a fluid having a similar index of refraction to that of proteins. We demonstrate MPM of intact, fixed, cleared mouse organs with penetration depths and fields of view in excess of 2 mm. MPM enables the creation of large 3-D data sets with flexibility in pixel format and ready access to intrinsic fluorescence and second-harmonic generation. We present high-resolution images and 3-D image stacks of the brain, small intestine, large intestine, kidney, lung, and testicle with image sizes as large as 4,096 x 4,096 pixels.


Asunto(s)
Acústica , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Animales , Encéfalo/citología , Intestinos/citología , Riñón/citología , Pulmón/citología , Masculino , Ratones , Ratones Endogámicos C57BL , Testículo/citología
15.
Bogotá, D.C; s.n; nov. 1990. 133 p. tab, graf.
Tesis en Español | LILACS | ID: lil-190013

RESUMEN

Se llevó a cabo un estudio de carácter epidemiológico que utilizó un diseño de prevalencia de periodo en la población del barrio Horizontes de Bogotá (estrato bajo) en individuos de ambos sexos entre los 15 y 44 años de edad, pertenecientes al programa de salud familiar de la Escuela Colombiana de Medicina en el año de 1990 (26 de Enero a 9 de Febrero). El universo de estudio fué de 142 personas, obteniéndose información de 124 individuos (87.32 por ciento). Se encontró una mayor frecuencia de sintomatología depresiva en las mujeres que en los hombres, con un 10,7 por ciento para depresión moderada y 8,2 por ciento para depresion severa, respectivamente. Ademas entre los síntomas depresivos estadísticamente significativos se encontraron en las mujeres: falta de apetito, insomnio, tristeza, llanto y pérdida de interes en las cosas; y en los hombres: dificultad en la toma de decisiones, tristeza y dificultad en disfrutar las actividades diarias. Se observa también una asociación estadística entre el nivel de escolaridad y el grado de depresión encontrandose mayor grado de depresión en niveles de educación primaria


Asunto(s)
Adolescente , Adulto , Trastorno Depresivo
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