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1.
Psychol Sci ; : 9567976241239915, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38648277

RESUMEN

This study investigated how relocation patterns affect disaster survivors' psychological stress on the diverse durations and spaces of relocation. It analyzed a 10-year data set of 1,236 families affected by 2009's Typhoon Morakot in Taiwan, identifying six relocation patterns through dynamic time warping (DTW). A hierarchical linear model was utilized, revealing the discernible impacts of environmental factors, sociocultural factors, and family-level socioeconomic factors on psychological stress. The study revealed that survivors who quickly found stable residences after the disaster initially experienced lower stress levels, but in the long term, their stress increased. Conversely, those with unstable residences experienced higher initial stress but lower long-term stress. Comparing similar patterns, we found that survivors who had more time for preparation and who sought opportunities, coped, or adapted to secondary stressors before long-distance relocation faced lower stress levels. These findings suggest that relocation patterns have a greater impact on the psychosocial stress of disaster survivors than time or relocation distance.

2.
Bioengineering (Basel) ; 10(11)2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-38002442

RESUMEN

Dental caries on the crown's surface is caused by the interaction of bacteria and carbohydrates, which then gradually alter the tooth's structure. In addition, calculus is the root of periodontal disease. Optical coherence tomography (OCT) has been considered to be a promising tool for identifying dental caries; however, diagnosing dental caries in the early stage still remains challenging. In this study, we proposed an ultrahigh-resolution OCT (UHR-OCT) system with axial and transverse resolutions of 2.6 and 1.8 µm for differentiating the early-stage dental caries and calculus. The same teeth were also scanned by a conventional spectral-domain OCT (SD-OCT) system with an axial resolution of 7 µm. The results indicated that early-stage carious structures such as small cavities can be observed using UHR-OCT; however, the SD-OCT system with a lower resolution had difficulty identifying it. Moreover, the estimated surface roughness and the scattering coefficient of enamel were proposed for quantitatively differentiating the different stages of caries. Furthermore, the thickness of the calculus can be estimated from the UHR-OCT results. The results have demonstrated that UHR-OCT can detect caries and calculus in their early stages, showing that the proposed method for the quantitative evaluation of caries and calculus is potentially promising.

3.
Cancer Sci ; 114(10): 3957-3971, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37496288

RESUMEN

Lysyl oxidase-like 2 (LOXL2) is a matrix-remodeling enzyme that has recently been identified as an important regulator of tumor progression and metastasis. This study discovered that LOXL2 expression in oral squamous cell carcinoma (OSCC) tissues was significantly associated with tumor clinical stage, lymph node metastasis and patients' overall survival time. LOXL2-overexpressing human buccal SCC TW2.6 (TW2.6/LOXL2) and hypopharyngeal SCC FaDu (FaDu/LOXL2) cells exhibited enhanced migration, invasion, epithelial-mesenchymal transition (EMT), and cancer stem cell (CSC) phenotypes, independently of its enzymatic activity. Moreover, TW2.6/LOXL2 significantly increased tumor-initiating frequency in SCID mice. We further demonstrated that LOXL2 increased the levels of interferon-induced protein with tetratricopeptide repeats 1 (IFIT1) and IFIT3 in TW2.6/LOXL2 and FaDu/LOXL2 cells. We also identified IFIT1 and IFIT3 as key downstream components of LOXL2 action in migration, invasion, EMT, and CSC phenotypes in TW2.6 and FaDu cells. Furthermore, a significant positive correlation between LOXL2 expression and IFIT1 and IFIT3 overexpression in human OSCC tissues was observed. In addition, TW2.6/LOXL2 and FaDu/LOXL2 cells were 3.3- to 3.6-fold more susceptible to the epidermal growth factor receptor (EGFR) inhibitor gefitinib than were their respective control cells. The antitumor effect of gefitinib on orthotopic TW2.6/LOXL2 xenograft tumor was fourfold higher than that on controls. Our results indicate that LOXL2 expression is a strong prognostic factor for OSCC and may be used as a marker to identify patients most likely to respond to EGFR-targeted therapy.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Animales , Ratones , Humanos , Gefitinib/farmacología , Carcinoma de Células Escamosas/patología , Proteína-Lisina 6-Oxidasa , Ratones SCID , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Proteínas de Unión al ARN/genética , Receptores ErbB , Regulación Neoplásica de la Expresión Génica , Transición Epitelial-Mesenquimal , Línea Celular Tumoral , Péptidos y Proteínas de Señalización Intracelular
4.
Diagnostics (Basel) ; 12(4)2022 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-35453872

RESUMEN

Fractional laser treatment is commonly used for dermatological applications, enabling effective induction of collagen regeneration and significantly reducing recovery time. However, it is challenging to observe laser-induced photodamage beneath the tissue surface in vivo, making the non-invasive evaluation of treatment outcomes difficult. For in vivo real-time study of the photodamage induced by fractional pulsed CO2 and Nd:YAG lasers commonly utilized for clinical therapy, a portable spectral-domain optical coherence tomography (SD-OCT) system was implemented for clinical studies. The photodamage caused by two lasers, including photothermal and photoacoustic effects, was investigated using OCT, together with the correlation between photodamage and exposure energy. Additionally, to investigate the change in the optical properties of tissue due to photodamage, the attenuation coefficients and damaged areas of normal skin and laser-treated skin were estimated for comparison. Finally, the recovery of the exposed skin with both lasers was also compared using OCT. The results show that OCT can be a potential solution for in vivo investigation of laser-induced tissue damage and quantitative evaluation.

5.
Small Methods ; 6(4): e2101228, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35212186

RESUMEN

Manipulation and precise delivery of optical energies in the regions of interest within specimens require different strategies. Hence, proper control of input beam parameters is a prerequisite. One of the prominent methods is metasurface optics, capable of crafting properties of light at nanoscales. Here, the generation of an abrupt autofocusing (AAF) beam by a nanophotonic metasurface for biomedical applications is demonstrated. Fluorescence guided laser microprofiling of mouse cardiac samples is experimentally investigated, using the AAF beam to deliver optical energy selectively to specific locations. In addition, photocoagulation of ex vivo swine skin tissue is performed and observed through optical coherence tomography. The results show great potentials for integrating metasurface optics to realize miniature laser surgery instruments for wide applications in biomedicine.


Asunto(s)
Rayos Láser , Óptica y Fotónica , Animales , Ratones , Porcinos
6.
Oral Dis ; 28(6): 1484-1495, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33655573

RESUMEN

OBJECTIVES: The myeloid-derived suppressor cells (MDSCs) frequently have a high expansion in cancer patients. This research explored whether administration of ß-glucan could increase anti-tumor immunity in oral squamous cell carcinoma (OSCC) patients. MATERIALS AND METHODS: This study evaluated the MDSC level of circulating blood as CD33+ /CD11b+ /HLA-DR-/low by flow cytometry in 30 healthy donors (HDs, group I), in 48 oral squamous cell carcinoma (OSCC) patients before and after 14-day preoperative administration of ß-glucan (group II), and in 52 OSCC patients without taking ß-glucan (group III). RESULTS: A significantly higher mean MDSC level was observed in 100 OSCC patients than in 30 HDs (p < .001). There was a significant reduction of the mean MDSC level in group II patients after taking ß-glucan (p < .001). Moreover, we discovered a significantly higher recurrence-free survival (RFS) in group II than in group III patients (p = .026). Finally, the multivariate Cox regression further identified the MDSC level ≤1% and administration of ß-glucan as more favorable prognostic factors for OSCC patients. CONCLUSION: Preoperative administration of ß-glucan can augment anti-tumor immunity and increase RFS rate via subversion of suppressive function of MDSC in OSCC patients.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Células Supresoras de Origen Mieloide , beta-Glucanos , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/patología , Neoplasias de Cabeza y Cuello/patología , Humanos , Células Supresoras de Origen Mieloide/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , beta-Glucanos/farmacología , beta-Glucanos/uso terapéutico
7.
Biomed Opt Express ; 12(8): 5139-5158, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-34513247

RESUMEN

A technique using Linnik-based optical coherence microscopy (OCM), with built-in fluorescence microscopy (FM), is demonstrated here to describe cellular-level morphology for fresh porcine and biobank tissue specimens. The proposed method utilizes color-coding to generate digital pseudo-H&E (p-H&E) images. Using the same camera, colocalized FM images are merged with corresponding morphological OCM images using a 24-bit RGB composition process to generate position-matched p-H&E images. From receipt of dissected fresh tissue piece to generation of stitched images, the total processing time is <15 min for a 1-cm2 specimen, which is on average two times faster than frozen-section H&E process for fatty or water-rich fresh tissue specimens. This technique was successfully used to scan human and animal fresh tissue pieces, demonstrating its applicability for both biobank and veterinary purposes. We provide an in-depth comparison between p-H&E and human frozen-section H&E images acquired from the same metastatic sentinel lymph node slice (∼10 µm thick), and show the differences, like elastic fibers of a tiny blood vessel and cytoplasm of tumor cells. This optical sectioning technique provides histopathologists with a convenient assessment method that outputs large-field H&E-like images of fresh tissue pieces without requiring any physical embedment.

8.
Biomed Opt Express ; 12(4): 2339-2352, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33996233

RESUMEN

Currently, the cochlear implantation procedure mainly relies on using a hand lens or surgical microscope, where the success rate and surgery time strongly depend on the surgeon's experience. Therefore, a real-time image guidance tool may facilitate the implantation procedure. In this study, we performed a systematic and quantitative analysis on the optical characterization of ex vivo mouse cochlear samples using two swept-source optical coherence tomography (OCT) systems operating at the 1.06-µm and 1.3-µm wavelengths. The analysis results demonstrated that the 1.06-µm OCT imaging system performed better than the 1.3-µm OCT imaging system in terms of the image contrast between the cochlear conduits and the neighboring cochlear bony wall structure. However, the 1.3-µm OCT imaging system allowed for greater imaging depth of the cochlear samples because of decreased tissue scattering. In addition, we have investigated the feasibility of identifying the electrode of the cochlear implant within the ex vivo cochlear sample with the 1.06-µm OCT imaging. The study results demonstrated the potential of developing an image guidance tool for the cochlea implantation procedure as well as other otorhinolaryngology applications.

9.
Biomed Opt Express ; 12(2): 722-736, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33680538

RESUMEN

Optical coherence tomography angiography (OCTA) can provide rapid, volumetric, and noninvasive imaging of tissue microvasculature without the requirement of exogenous contrast agents. To investigate how A-scan rate and interscan time affected the contrast and dynamic range of OCTA, we developed a 1.06-µm swept-source OCT system enabling 100-kHz or 200-kHz OCT using two light sources. After system settings were carefully adjusted, almost the same detection sensitivity was achieved between the 100-kHz and 200-kHz modalities. OCTA of ear skin was performed on five mice. We used the variable interscan time analysis algorithm (VISTA) and the designated scanning protocol with OCTA images reconstructed through the correlation mapping method. With a relatively long interscan time (e.g., 12.5 ms vs. 6.25 ms for 200-kHz OCT), OCTA can identify more intricate microvascular networks. OCTA image sets with the same interscan time (e.g., 12.5 ms) were compared. OCTA images acquired with a 100-kHz A-scan rate showed finer microvasculature than did other imaging modalities. We performed quantitative analysis on the contrast from OCTA images reconstructed with different A-scan rates and interscan time intervals in terms of vessel area, total vessel length, and junction density.

10.
Nanotechnology ; 31(32): 324002, 2020 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-32453710

RESUMEN

Inorganic perovskite quantum dots (IPQDs) such as cesium lead halide (CsPbX3, X = Cl, Br and I) quantum dots have attracted much attention for developing cadmium-free quantum light-emitting displays (QLEDs) based on outstanding light emission properties including narrow full width at half maximum (FWHM), tunable bandgap and ultrahigh (>90%) photoluminescence quantum yield (PLQY). Nevertheless, their poor stability under ambient conditions, at high temperature or under continuous light irradiation is the main problem for practical applications. In this study, a new method is proposed to effectively stabilize CsPbBr3 IPQDs by synthesizing them with sulfate-functionalized cellulose nanocrystals (CNCs) at room temperature without using traditional quantum dot stabilizers such as oleylamine (OLA) and oleic acid (OA). The as-prepared CsPbBr3 IPQD/CNC hybrid paper-like films are highly stable and the relative photoluminescence (PL) intensity can be maintained at 92% under continuous UV light (306 nm, 15 W) illumination for 130 h, >99% at high temperature (100 °C) for 130 h, and >99% in ambient conditions for 15 d. Additionally, the PLQY and FWHM of IPQD/CNC are 45.69% and 22 nm, respectively. The ultrahigh stability and narrow FWHM characteristics proposed here for IPQD/CNC hybrid films can provide new possibilities for practical applications in the future development of IPQD-related devices.

11.
Head Neck ; 42(1): 5-13, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31571325

RESUMEN

BACKGROUND: Nucleophosmin/nucleoplasmin family 1 (NPM1) has broad physiological functions, such as DNA replication, transcription, ribosome biogenesis, and centrosome replication. This study explored the clinicopathological importance of NPM1 as a prognostic marker for oral squamous cell carcinoma (OSCC). METHODS: We collected specimens from 96 OSCC, 45 oral epithelial dysplasia (OED), and 29 normal oral mucosa (NOM). NPM1 expression was analyzed via immunohistochemistry. Correlations between NPM1and clinical parameters were analyzed using Student t test, chi-squared test, and Kaplan-Meier product-limit method. RESULTS: The NPM1 labeling indices (LIs) were significantly higher in OSCCs than in NOM and oral OED. Higher NPM1 expression was significantly correlated with larger tumor size, nodal metastasis, and advanced clinical stage. Multivariate analysis revealed that higher NPM1 LIs were an unfavorable independent factor for survival. CONCLUSIONS: Upregulated NPM1 is an independent biomarker of poor prognosis and NPM1 inhibitors may be promising in molecular targeted therapy against OSCC.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Proteínas Nucleares/genética , Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas/genética , Progresión de la Enfermedad , Humanos , Mucosa Bucal , Nucleofosmina , Nucleoplasminas , Pronóstico , Carcinoma de Células Escamosas de Cabeza y Cuello , Taiwán
12.
Biomed Opt Express ; 10(11): 5687-5702, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31799040

RESUMEN

In this study, a Q-switch pumped supercontinuum laser (QS-SCL) is used as a light source for in vivo imaging via ultrahigh-resolution optical coherence tomography and angiography (UHR-OCT/OCTA). For this purpose, an OCT system based on a spectral-domain detection scheme is constructed, and a spectrometer with a spectral range of 635 - 875 nm is designed. The effective full-width at half maximum of spectrum covers 150 nm, and the corresponding axial and transverse resolutions are 2 and 10 µm in air, respectively. The relative intensity noise of the QS-SCL and mode-locked SCL is quantitatively compared. Furthermore, a special processing algorithm is developed to eliminate the intrinsic noise of QS-SCL. This work demonstrates that QS-SCLs can effectively reduce the cost and size of UHR-OCT/OCTA instruments, making clinical applications feasible.

13.
Sci Rep ; 9(1): 17154, 2019 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-31748675

RESUMEN

Enamel is the outermost layer of the tooth that protects it from invasion. In general, an acidic environment accelerates tooth demineralization, leading to the formation of cavities. Scanning electron microscopy (SEM) is conventionally used as an in vitro tool for the observation of tooth morphology changes with acid attacks. Yet, SEM has intrinsic limitations for the potential application of in vivo detection in the early demineralization process. In this study, a high-resolution optical coherence tomography (OCT) system with the axial and transverse resolutions of 2.0 and 2.7 µm in teeth has been utilized for characterizing the effect of the acidic environment (simulated by phosphoric acid) on the enamel topology. The scattering coefficient and the surface roughness of enamel can be directly derived from the OCT results, enabling a quantitative evaluation of the topology changes with demineralization. The dynamic process induced by the acid application is also recorded and analyzed with OCT, depicting the evolution of the demineralization process on enamel. Notably, the estimated enamel scattering coefficient and surface roughness significantly increase with the application time of acid and the results illustrate that the values of both parameters after demineralization are significantly larger than those obtained before the demineralization, illustrating both parameters could be effective to differentiate the healthy and demineralized teeth and determine the severity. The obtained results unambiguously illustrate that demineralization of the tooth surface can be successfully detected by OCT and further used as an indicator of early-stage cavity formation.


Asunto(s)
Esmalte Dental/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Desmineralización Dental/diagnóstico por imagen , Desmineralización Dental/diagnóstico , Diagnóstico Precoz , Humanos , Erosión de los Dientes/diagnóstico
14.
Nat Med ; 25(10): 1512-1518, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31591601

RESUMEN

Insulin and other injectable biologic drugs have transformed the treatment of patients suffering from diabetes1,2, yet patients and healthcare providers often prefer to use and prescribe less effective orally dosed medications3-5. Compared with subcutaneously administered drugs, oral formulations create less patient discomfort4, show greater chemical stability at high temperatures6, and do not generate biohazardous needle waste7. An oral dosage form for biologic medications is ideal; however, macromolecule drugs are not readily absorbed into the bloodstream through the gastrointestinal tract8. We developed an ingestible capsule, termed the luminal unfolding microneedle injector, which allows for the oral delivery of biologic drugs by rapidly propelling dissolvable drug-loaded microneedles into intestinal tissue using a set of unfolding arms. During ex vivo human and in vivo swine studies, the device consistently delivered the microneedles to the tissue without causing complete thickness perforations. Using insulin as a model drug, we showed that, when actuated, the luminal unfolding microneedle injector provided a faster pharmacokinetic uptake profile and a systemic uptake >10% of that of a subcutaneous injection over a 4-h sampling period. With the ability to load a multitude of microneedle formulations, the device can serve as a platform to orally deliver therapeutic doses of macromolecule drugs.


Asunto(s)
Administración Cutánea , Sistemas de Liberación de Medicamentos , Agujas , Animales , Diseño de Equipo , Humanos , Insulina/farmacología , Porcinos
15.
World J Gastroenterol ; 25(16): 1997-2009, 2019 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-31086467

RESUMEN

BACKGROUND: Chronic radiation proctopathy (CRP) occurs as a result of pelvic radiation therapy and is associated with formation of abnormal vasculature that may lead to persistent rectal bleeding. While incidence is declining due to refinement of radiation delivery techniques, CRP remains one of the major complications of pelvic radiation therapy and significantly affects patient quality of life. Radiofrequency ablation (RFA) is an emerging treatment modality for eradicating abnormal vasculature associated with CRP. However, questions remain regarding CRP pathophysiology and optimal disease management. AIM: To study feasibility of optical coherence tomography angiography (OCTA) for investigating subsurface vascular alterations in CRP and response to RFA treatment. METHODS: Two patients with normal rectum and 8 patients referred for, or undergoing endoscopic RFA treatment for CRP were imaged with a prototype ultrahigh-speed optical coherence tomography (OCT) system over 15 OCT/colonoscopy visits (2 normal patients, 5 RFA-naïve patients, 8 RFA-follow-up visits). OCT and OCTA was performed by placing the OCT catheter onto the dentate line and rectum without endoscopic guidance. OCTA enabled depth-resolved microvasculature imaging using motion contrast from flowing blood, without requiring injected dyes. OCTA features of normal and abnormal microvasculature were assessed in the mucosa and submucosa. Blinded reading of OCTA images was performed to assess the association of abnormal rectal microvasculature with CRP and RFA treatment, and rectal telangiectasia density endoscopic scoring. RESULTS: OCTA/OCT images are intrinsically co-registered and enabled depth-resolved visualization of microvasculature in the mucosa and submucosa. OCTA visualized normal vascular patterns with regular honeycomb patterns vs abnormal vasculature with distorted honeycomb patterns and ectatic/tortuous microvasculature in the rectal mucosa. Normal arterioles and venules < 200 µm in diameter versus abnormal heterogenous enlarged arterioles and venules > 200 µm in diameter were visualized in the rectal submucosa. Abnormal mucosal vasculature occurred in 0 of 2 normal patients and 3 of 5 RFA-naïve patients, while abnormal submucosal vasculature occurred more often, in 1 of 2 normal patients and 5 of 5 RFA-naïve patients. After RFA treatment, vascular abnormalities decreased, with abnormal mucosal vasculature observed in 0 of 8 RFA-follow-up visits and abnormal submucosal vasculature observed in only and 2 of 8 RFA-follow-up visits. CONCLUSION: OCTA visualizes depth-resolved microvascular abnormalities in CRP, allowing assessment of superficial features which are endoscopically visible as well as deeper vasculature which cannot be seen endoscopically. OCTA/OCT of the rectum can be performed in conjunction with, or independently from endoscopy. Further studies are warranted to investigate if OCTA/OCT can elucidate pathophysiology of CRP or improve management.


Asunto(s)
Angiografía , Microvasos/diagnóstico por imagen , Traumatismos por Radiación/cirugía , Enfermedades del Recto/cirugía , Tomografía de Coherencia Óptica , Anciano , Anciano de 80 o más Años , Enfermedad Crónica/terapia , Estudios de Factibilidad , Estudios de Seguimiento , Humanos , Masculino , Microvasos/efectos de la radiación , Microvasos/cirugía , Proyectos Piloto , Proctoscopía , Calidad de Vida , Traumatismos por Radiación/diagnóstico por imagen , Traumatismos por Radiación/etiología , Ablación por Radiofrecuencia , Enfermedades del Recto/diagnóstico por imagen , Enfermedades del Recto/etiología , Recto/irrigación sanguínea , Recto/diagnóstico por imagen , Recto/cirugía , Resultado del Tratamiento
16.
Endoscopy ; 51(4): 355-359, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30261534

RESUMEN

BACKGROUND: This study aimed to evaluate the use of ultrahigh-speed volumetric en face and cross-sectional optical coherence tomography (OCT) with micromotor catheters for the in vivo assessment of Barrett's esophagus and dysplasia. METHODS: 74 OCT datasets with correlated biopsy/endoscopic mucosal resection histology (49 nondysplastic Barrett's esophagus [NDBE], 25 neoplasia) were obtained from 14 patients with Barrett's esophagus and a history of dysplasia and 30 with NDBE. The associations between irregular mucosal patterns on en face OCT, absence of mucosal layering, surface signal > subsurface, and > 5 atypical glands on cross-sectional OCT vs. histology and treatment history were assessed by three blinded readers. RESULTS: Atypical glands under irregular mucosal patterns occurred in 75 % of neoplasia (96 % of treatment-naïve neoplasia) vs. 30 % of NDBE datasets (43 % of short- and 18 % of long-segment NDBE). Mucosal layering was absent in 35 % of neoplasia and 50 % of NDBE datasets, and surface signal > subsurface occurred in 29 % of neoplasia and 30 % of NDBE datasets. CONCLUSIONS: Atypical glands under irregular mucosal patterns are strongly associated with neoplasia, suggesting potential markers for dysplasia and a role in pathogenesis.


Asunto(s)
Esófago de Barrett , Mucosa Esofágica , Neoplasias Esofágicas , Lesiones Precancerosas , Tomografía de Coherencia Óptica/métodos , Esófago de Barrett/diagnóstico , Esófago de Barrett/patología , Biopsia/métodos , Mucosa Esofágica/diagnóstico por imagen , Mucosa Esofágica/patología , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/patología , Esofagoscopía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Lesiones Precancerosas/diagnóstico por imagen , Lesiones Precancerosas/patología , Reproducibilidad de los Resultados
17.
Optica ; 5(1): 36-43, 2018 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-29682598

RESUMEN

Devices that perform wide field-of-view (FOV) precision optical scanning are important for endoscopic assessment and diagnosis of luminal organ disease such as in gastroenterology. Optical scanning for in vivo endoscopic imaging has traditionally relied on one or more proximal mechanical actuators, limiting scan accuracy and imaging speed. There is a need for rapid and precise two-dimensional (2D) microscanning technologies to enable the translation of benchtop scanning microscopies to in vivo endoscopic imaging. We demonstrate a new cycloid scanner in a tethered capsule for ultrahigh speed, side-viewing optical coherence tomography (OCT) endomicroscopy in vivo. The cycloid capsule incorporates two scanners: a piezoelectrically actuated resonant fiber scanner to perform a precision, small FOV, fast scan and a micromotor scanner to perform a wide FOV, slow scan. Together these scanners distally scan the beam circumferentially in a 2D cycloid pattern, generating an unwrapped 1 mm × 38 mm strip FOV. Sequential strip volumes can be acquired with proximal pullback to image centimeter-long regions. Using ultrahigh speed 1.3 µm wavelength swept-source OCT at a 1.17 MHz axial scan rate, we imaged the human rectum at 3 volumes/s. Each OCT strip volume had 166 × 2322 axial scans with 8.5 µm axial and 30 µm transverse resolution. We further demonstrate OCT angiography at 0.5 volumes/s, producing volumetric images of vasculature. In addition to OCT applications, cycloid scanning promises to enable precision 2D optical scanning for other imaging modalities, including fluorescence confocal and nonlinear microscopy.

18.
Biomed Opt Express ; 9(9): 4235-4245, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-30615717

RESUMEN

Ultraviolet (UV) rays have been identified as a carcinogen with long-term irradiation and are an important risk factor for skin cancer. Here, we report the use of optical coherence tomography/optical coherence tomography angiography (OCT/OCTA) to study acute UV-induced effects on skin in vivo. To understand the relationship between the acute effects and irradiated UV power density, three groups were irradiated with different power densities in our experiments. Furthermore, the same skin area was repeatedly scanned with OCT during UV irradiation to investigate the progress of the induced acute effects and after irradiation for observation of skin recovery. Subsequently, the OCT/OCTA results were quantitatively analyzed to acquire skin thickness and blood-vessel density for comparison. UV-induced acute effects on morphology and microcirculation can be identified from OCT/OCTA results, which showed the increases in the skin thickness and blood-vessel density and even severe damage types such as blisters. The results of quantitative analyses also illustrated that the severity of damage induced by UV irradiation can be distinguished and the skin recovery can be monitored with OCT. Our results indicate that OCT can be a promising tool for early detection of UV-induced acute skin damage.

20.
Opt Lett ; 42(16): 3193-3196, 2017 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-28809905

RESUMEN

Endoscopic optical coherence tomography (OCT) instruments are mostly side viewing and rely on at least one proximal scan, thus limiting accuracy of volumetric imaging and en face visualization. Previous forward-viewing OCT devices had limited axial scan speeds. We report a forward-viewing fiber scanning 3D-OCT probe with 900 µm field of view and 5 µm transverse resolution, imaging at 1 MHz axial scan rate in the human gastrointestinal tract. The probe is 3.3 mm diameter and 20 mm rigid length, thus enabling passage through the endoscopic channel. The scanner has 1.8 kHz resonant frequency, and each volumetric acquisition takes 0.17 s with 2 volumes/s display. 3D-OCT and angiography imaging of the colon was performed during surveillance colonoscopy.

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