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1.
World J Urol ; 41(12): 3551-3557, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37831155

RESUMO

PURPOSE: To investigate if increased tubular damage biomarker can predict pathologically upstaged renal cell carcinoma (RCC), which may possess sub-radiologic invasive behavior, leading to surrounding tubular damage. MATERIALS AND METHODS: We examined 1563 patients with surgically resected RCC between March 2016 and June 2021 from the prospective database SUPER-RCC-Nx. Exclusion criteria were cancer not originating from the kidneys, benign renal tumor, and end-stage renal disease. RESULTS: Of 1297 patients, 131 had a clinically high T stage (T3-4), whereas 1166 had a low one. Patients with a clinically low T stage were subgrouped into identical-stage (n = 1041) and upstaged (n = 125) groups, who were confirmed as a pathologically high T stage. The upstaged group had older age (p = 0.003), larger tumor size (5.72 ± 3.24 vs. 3.12 ± 2.08, p < 0.001), higher Fuhrman grade (grades 3-4) (57.3% vs. 47.1%, p = 0.032), and higher urine N-acetyl-beta-D-glucosaminidase/creatinine (NAG/Cr) (5.13 ± 4.78 vs. 4.05 ± 2.84, p = 0.026). Tumor size (> 4 cm; odds ratio = 10.2, p < 0.001) and urine NAG/Cr (odds ratio = 1.16, p = 0.003) were independently associated with pathological upstaging in patients with normal renal function, while age and tumor size were significant risk factors in those with decreased renal function. The receiver operating characteristic curve analysis showed that the model using tumor size and urine NAG/Cr strongly predicted pathological upstaging (area under the curve, 0.84). CONCLUSION: Urine NAG/Cr may be a useful biomarker predicting pathologically upstaged RCC. Clinicians should be prudent in making management decisions when a large RCC is accompanied by an increased urine NAG/Cr.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/cirurgia , Carcinoma de Células Renais/patologia , Neoplasias Renais/cirurgia , Neoplasias Renais/patologia , Rim/patologia , Creatinina , Biomarcadores/urina
2.
Opt Lett ; 45(19): 5327-5330, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33001885

RESUMO

We report on an akinetic actively-mode-locked wavelength-swept laser (ASL) with a sweep that is highly linear in wavenumber. By tailoring the drive waveform of the intracavity modulator, the wavenumber sweep was further linearized to enable high fidelity frequency-domain interferometric ranging without resampling of the acquired data. Used for catheter-based optical coherence tomography, the ASL showed comparable imaging performance to a state-of-the-art polygon-based wavelength-swept source at a matching sweep rate of 103.6 kHz, a duty cycle of 95%, and a bandwidth of 100 nm, centered at 1330 nm.

3.
Opt Lett ; 43(21): 5476-5479, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30383038

RESUMO

We demonstrate a real-time surface plasmon resonance imaging (SPRi) system based on a wavelength-swept laser. Compared to conventional spectral-modulation SPRi using white light source and spectral filtering, the proposed system has a higher scan rate to detect rapid changes in refractive index and a higher output power for large-area illumination. This SPRi system achieves scan rates faster than 12 Hz, simultaneously obtaining SPR dip positions over full illumination fields of 12×12 mm. Using the wavelength-swept laser, two-dimensional biomolecular array imaging can be acquired with a high dynamic detection range (7.67×10-3 refractive index unit (RIU)) as well as high sensitivity (6501 nm/RIU) and resolution (1.89×10-6 RIU).

4.
Sensors (Basel) ; 18(12)2018 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-30477260

RESUMO

A new type of quasi-distributed sensor system is implemented using an active mode locking (AML) laser cavity with multiple partially reflecting segments. The mode locking frequency of the AML laser is linearly proportional to the overall lasing cavity length. To implement multiple resonators having multiple reflection points installed in a sensing fiber, two types of partial reflectors (PRs) are implemented for an in-line configuration, one with fiber Bragg grating and the other with a fiber Fabry⁻Perot interferometer. Since the laser has oscillated only when the modulation frequencies for the mode locking frequency match with the corresponding resonator lengths, it is possible to read the multiple partially reflecting segments along the sensing fiber. The difference between two corresponding mode locking frequencies is changing proportionally with the segment length variation between two PRs upon strain application. The segment length change caused by the applied strain can be successfully measured with a linear sensitivity between mode locking frequency and displacement, linearity over 0.99, and spatial position resolution below meter order.

5.
Sensors (Basel) ; 16(1)2016 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-26805840

RESUMO

We have developed a modified optical frequency domain imaging (OFDI) system that performs parallel imaging of three-dimensional (3D) surface profiles by using the space division multiplexing (SDM) method with dual-area swept sourced beams. We have also demonstrated that 3D surface information for two different areas could be well obtained in a same time with only one camera by our method. In this study, double field of views (FOVs) of 11.16 mm × 5.92 mm were achieved within 0.5 s. Height range for each FOV was 460 µm and axial and transverse resolutions were 3.6 and 5.52 µm, respectively.

6.
J Clin Med ; 12(8)2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37109157

RESUMO

OBJECTIVES: The aim of this study was to evaluate the level of hematuria and the presence of clots during retrograde intrarenal surgery (RIRS) and miniaturized percutaneous nephrolithotomy (mPCNL) to predict surgical outcomes. MATERIALS AND METHODS: The data of patients who underwent RIRS and mPCNL were analyzed separately. A hematuria grading (HG) system was classified into five grades based on the presence of blood clots and any visible stones according to the irrigation settings. Inter-observer reliability of the grading system was assessed using intra-class correlation and Spearman's rho. RESULTS: The HG system showed high agreement among examiners, with high intra-class reliability and a strong correlation between RIRS and mPCNL groups. The stone density of the Houns-field unit was the most important factor in determining the hematuria across the development and validation groups of RIRS and mPCNL patients. Multivariate logistic regression analysis showed that the HG system was a significant predictor for remnant stones in the PCNL group and the probability of acute pyelonephritis or sepsis in the RIRS group. The high hematuria group showed lower basketing difficulty with the basket with a blue marker instrument than with others. CONCLUSIONS: The new HG system shows excellent inter-observer reliability and a correlation with a gradual increase in stone density and surgical difficulty.

7.
Investig Clin Urol ; 64(5): 457-465, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37668201

RESUMO

PURPOSE: To compare renal function change by urinary diversion (UD) type (ileal conduit [IC] vs. neobladder [NB]) in patients with a single kidney who underwent radical cystectomy (RC) due to bladder cancer. MATERIALS AND METHODS: We evaluated the renal function change in 86 patients with a single kidney who underwent RC between January 1999 and August 2022. Renal function was assessed using serum creatinine, serum estimated glomerular filtration rate (eGFR), eGFR difference value (preoperative and follow-up values), and eGFR difference proportion (eGFR difference value/preoperative eGFR) at 1, 3, 6, 12, 24, 36, 48, and 60 months. In addition, multiple definitions of eGFR decline were evaluated: 10 points, 10%, and 20% decline in eGFR. Cox regression models were used to identify risk factors of eGFR decline-free, recurrence-free, overall, and cancer-specific survival rates. RESULTS: A total of 54 patients (62.8%) underwent IC, whereas 32 (37.2%) underwent NB. Baseline characteristics were similar between the two groups except for age and body mass index. Renal functions over time by various methods did not differ significantly between the IC and NB groups. Furthermore, eGFR decline-free survival rate using different definitions was similar between the IC and NB groups. Overall survival, recurrence-free survival, and cancer-specific-free survival rates were not different between the IC and NB groups. CONCLUSIONS: UD type (IC vs. NB) did not impact the renal function change of patients with a single kidney who underwent RC. Therefore, patients with a single kidney might be considered to be an indication of NB.


Assuntos
Carcinoma de Células de Transição , Rim Único , Neoplasias da Bexiga Urinária , Derivação Urinária , Humanos , Neoplasias da Bexiga Urinária/cirurgia , Carcinoma de Células de Transição/cirurgia , Cistectomia/efeitos adversos , Derivação Urinária/efeitos adversos , Rim/cirurgia , Rim/fisiologia
9.
PLoS One ; 17(7): e0272078, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35901186

RESUMO

The development of scientific technology for art authentication has elicited multidimensional evidence to distinguish forgeries from original artwork. Here, we analyzed the three-dimensional morphology of cracks that contain information, such as the painting features of artworks, using optical coherence tomography. The forgeries were produced by an expert from original oil paintings with cracks that occur owing to paint drying, canvas aging, and physical damage. Parameters, such as shape, width, and depth, were compared based on the cross-sectional images of the original and fake cracks. The original cracks were rectangular and inverted, but the fake cracks were relatively simple inverted triangles. The original cracks were as deep as the thickness of the upper layer and mostly were "thin/deep" or "wide/shallow". The fake cracks were observed to be "'thin/shallow" or "wide/deep". This study aims to improve the understanding of crack characteristics and promote the development of techniques for determining art authenticity.


Assuntos
Pinturas , Pintura , Tomografia de Coerência Óptica
10.
Sex Med ; 8(4): 643-649, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32773264

RESUMO

INTRODUCTION: Sexual activity can be broadly defined to include not only sexual intercourse but also physical intimacy. However, most studies of sexual activity in older adults have a limited focus on sexual intercourse only. AIM: The aim was to investigate sexual activities including sexual intercourse and physical intimacy in community-dwelling older Korean adults. METHODS: This study was based on cross-sectional data to measure sexual activities (sexual intercourse and physical intimacy) in 209 participants (100 men and 109 women) aged 65 years or older. Sexual intercourse and physical intimacy were defined as vaginal penetration and as any sexual behavior with sexual arousing (eg, kissing, caressing), respectively. Erectile dysfunction was evaluated by the use of the International Index of Erectile Function questionnaire, and female sexual dysfunction was evaluated by Female Sexual Function Index scores. MAIN OUTCOME MEASURE: Trained interviewers collected the survey information on sexual activities in the last 6 months at the senior welfare center. RESULTS: The participants' mean age was 73.4 ± 4.8 years (men, 74.2 ± 5.0 years; women, 71.6 ± 5.3 years). The prevalence of erectile dysfunction was 91.0% (91/100), and the prevalence of female sexual dysfunction was 96.3% (105/109). In the previous 6 months, 122 participants (58.4%) reported sexual activities, and men reported more sexual activities than women (P = .001). A total of 69.6% of men and 41.9% of women engaged in sexual activity with intercourse, whereas 30.4% of men and 58.1% of women engaged in physical intimacy only. The physical intimacy-only group was more likely to have erectile dysfunction or female sexual dysfunction than the sexual intercourse group (P = .035 and P = .012, respectively). CONCLUSIONS: Although sexual intercourse is an important part of sexual activity, our study results suggest that physical intimacy is also a considerable component of sexual activity that should not be neglected in older adults, especially in women. Our findings imply that health-care professionals need to consider physical intimacy as part of sexual activity in the assessment of geriatric patients with sexual dysfunction. Chung HS, Kim GH, Shin M-H, et al. Physical Intimacy Is an Important Part of Sexual Activities: Korean Older Adults Study. Sex Med 2020;8:643-649.

11.
J Biomed Opt ; 24(7): 1-9, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31290292

RESUMO

A multi-spectral laser speckle contrast imaging (MS-LSCI) system is proposed using only a single wavelength-swept laser, which provides both highly coherent and multi-spectral outputs to simultaneously generate laser speckle contrast images and multi-spectral images, respectively. Using a laser light swept from 770 to 821 nm at a repetition rate of 5 Hz and a CCD camera of 335 fps, 67 multi-spectral frame images are acquired in 0.76 nm wavebands over 51 nm spectral range. The spectral sub-windowing method of single wavelength-swept laser source is used to solve the lack of spectral information from a few individual light sources, which is a limitation of conventional MS-LSCI systems. In addition to the speckle flow index from the LSCI frames, the multi-spectrally encoded images can generate additional images of spectral absorbance. To further examine the performance of the MS-LSCI system, an in vivo cuff-induced ischemia experiment was conducted to show the real-time imaging of hemodynamic and blood oxygen saturation changes simultaneously over the entire 2.5 cm × 4.5 cm field of view.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Lasers , Imagem Óptica/métodos , Estudos de Viabilidade , Dedos/irrigação sanguínea , Dedos/diagnóstico por imagem , Hemodinâmica/fisiologia , Humanos , Isquemia/sangue , Isquemia/diagnóstico por imagem , Imagem Óptica/instrumentação , Oxigênio/sangue , Oxiemoglobinas/análise , Imagens de Fantasmas
12.
Sci Rep ; 9(1): 3921, 2019 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-30850674

RESUMO

Distributed optical fiber sensors (DOFS) based on Raman, Brillouin, and Rayleigh scattering have recently attracted considerable attention for various sensing applications, especially large-scale monitoring, owing to their capacity for measuring strain or temperature distributions. However, ultraweak backscatter signals within optical fibers constitute an inevitable problem for DOFS, thereby increasing the burden on the entire system in terms of limited spatial resolution, low measurement speed, high system complexity, or high cost. We propose a novel resonance frequency mapping for a real-time quasi-distributed fiber optic sensor based on identical weak fiber Bragg gratings (FBG), which has stronger reflection signals and high sensitivity to multiple sensing parameters. The resonance configuration, which amplifies optical signals during multiple round-trip propagations, can simply and efficiently address the intrinsic problems in conventional single round-trip measurements for identical weak FBG sensors, such as crosstalk and optical power depletion. Moreover, it is technically feasible to perform individual measurements for a large number of quasi-distributed identical weak FBGs with relatively high signal-to-noise ratio (SNR), low crosstalk, and low optical power depletion. By mapping the resonance frequency spectrum, the dynamic response of each identical weak FBG is rapidly acquired in the order of kilohertz, and direct interrogation in real time is possible without time-consuming computation, such as fast Fourier transformation (FFT). This resonance frequency spectrum is obtained on the basis of an all-fiber electro-optic configuration that allows simultaneous measurement of quasi-distributed strain responses with high speed (>5 kHz), high stability (~2.4 µÎµ), and high linearity (R2 = 0.9999).

13.
Sci Rep ; 8(1): 17660, 2018 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-30518926

RESUMO

Optical coherence tomography (OCT) is a noninvasive imaging modality that can provide high-resolution, cross-sectional images of tissues. Especially in retinal imaging, OCT has become one of the most valuable imaging tools for diagnosing eye diseases. Considering the scattering and absorption properties of the eye, the 1000-nm OCT system is preferred for retinal imaging. In this study, we describe the use of an akinetic swept-source OCT system based on a pulse-modulated active mode locking (AML) fiber laser at a 1080-nm wavelength for in-vivo human retinal imaging. The akinetic AML wavelength-swept fiber laser was constructed with polarization-maintaining fiber that has an average linewidth of 0.625 nm, a spectral bandwidth of 81.15 nm, and duty ratio of 90% without the buffering method. We successfully obtained in-vivo human retinal images using the proposed OCT system without the additional k-clock and the frequency shifter that provides a wide field of view of 43.1°. The main retina layers, such as the retinal pigment epithelium, can be distinguished from the OCT image with an axial resolution of 6.3 µm with this OCT system.


Assuntos
Retina/diagnóstico por imagem , Tomografia de Coerência Óptica/instrumentação , Algoritmos , Desenho de Equipamento , Humanos , Imageamento Tridimensional/instrumentação , Imageamento Tridimensional/métodos , Tomografia de Coerência Óptica/métodos
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