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1.
Diagnostics (Basel) ; 14(3)2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38337789

RESUMEN

BACKGROUND: Claudin-1 becomes overexpressed during the transformation of normal colonic mucosa to colorectal cancer (CRC). METHODS: Patient-derived organoids expressed clinically relevant target levels and genetic heterogeneity, and were established from human adenoma and normal colons. Colonoids were implanted orthotopically in the colon of immunocompromised mice. This pre-clinical model of CRC provides an intact microenvironment and representative vasculature. Colonoid growth was monitored using white light endoscopy. A peptide specific for claudin-1 was fluorescently labeled for intravenous administration. NIR fluorescence images were collected using endoscopy and endomicroscopy. RESULTS: NIR fluorescence images collected using wide-field endoscopy showed a significantly greater target-to-background (T/B) ratio for adenoma versus normal (1.89 ± 0.35 and 1.26 ± 0.06) colonoids at 1 h post-injection. These results were confirmed by optical sections collected using endomicroscopy. Optical sections were collected in vivo with sub-cellular resolution in vertical and horizontal planes. Greater claudin-1 expression by individual epithelial cells in adenomatous versus normal crypts was visualized. A human-specific cytokeratin stain ex vivo verified the presence of human tissues implanted adjacent to normal mouse colonic mucosa. CONCLUSIONS: Increased claudin-1 expression was observed from adenoma versus normal colonoids in vivo using imaging with wide field endoscopy and endomicrosopy.

2.
J Biomed Opt ; 29(Suppl 1): S11514, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38169937

RESUMEN

Significance: A Fabry-Perot (FP) polymer film sensor can be used to detect acoustic waves in a photoacoustic endoscope (PAE) if the dimensions can be adequately scaled down in size. Current FP sensors have limitations in size, sensitivity, and array configurability. Aim: We aim to characterize and demonstrate the imaging performance of a miniature FP sensor to evaluate the effects of reduced size and finite dimensions. Approach: A transfer matrix model was developed to characterize the frequency response of a multilayer miniature FP sensor. An analytical model was derived to describe the effects of a substrate with finite thickness. Finite-element analysis was performed to characterize the temporal response of a sensor with finite dimensions. Miniature 2×2 mm2 FP sensors were designed and fabricated using gold films as reflective mirrors on either side of a parylene C film deposited on a glass wafer. A single-wavelength laser was used to interrogate the sensor using illumination delivered by fiber subprobes. Imaging phantoms were used to verify FP sensor performance, and in vivo images of blood vessels were collected from a live mouse. Results: The finite thickness substrate of the FP sensor resulted in echoes in the time domain signal that could be removed by back filtering. The substrate acted as a filter in the frequency domain. The finite lateral sensor dimensions produced side waves that could be eliminated by surface averaging using an interrogation beam with adequate diameter. The fabricated FP sensor produced a noise-equivalent pressure = 0.76 kPa, bandwidth of 16.6 MHz, a spectral full-width at-half-maximum = 0.2886 nm, and quality factor Q=2694. Photoacoustic images were collected from phantoms and blood vessels in a live mouse. Conclusions: A miniature wafer-based FP sensor design has been demonstrated with scaled down form factor for future use in PAE.


Asunto(s)
Acústica , Polímeros , Animales , Ratones , Polímeros/química , Análisis Espectral , Fantasmas de Imagen , Endoscopía Gastrointestinal
3.
Biomed Opt Express ; 14(8): 4277-4295, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37799693

RESUMEN

A side-view dual axes confocal endomicroscope is demonstrated that can be inserted repetitively in hollow organs of genetically engineered mice for in vivo real-time imaging in horizontal and vertical planes. Near infrared (NIR) excitation at λex = 785 nm was used. A monolithic 3-axis parametric resonance scan mirror was fabricated using micro-electro-mechanical systems (MEMS) technology to perform post-objective scanning in the distal end of a 4.19 mm diameter instrument. Torsional and serpentine springs were designed to "switch" the mode of imaging between vertical and horizontal planes by tuning the actuation frequency. This system demonstrated real-time in-vivo images in horizontal and vertical planes with 310 µm depth and 1.75 and 7.5 µm lateral and axial resolution. Individual cells and discrete mucosal structures could be identified.

4.
Asian Pac J Cancer Prev ; 15(14): 5729-32, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25081693

RESUMEN

BACKGROUND: Cervical cancer is the third most common gynecological cancer and a widespread malignancy in women, accounting for a large proportion of the cancer burden in developing countries. We compared accuracy of MRI staging with clinical staging and also concordance between the two methods for newly diagnosed patients with cervical cancer, using clinical staging as the reference. MATERIALS AND METHODS: This prospective study was conducted on 27 newly diagnosed patients with cervical cancer from Imam Khomeini hospital from June 2012 to Feb 2014. New cases of cervical cancer with positive PAP test were staged separately with a clinical exam based on the FIGO system by a gynecologist, oncologist and also with MRI by an expert radiologist. Then we compared the predicted stage for each patient with the two methods. RESULTS: Based on clinical staging 9 patients (33%) were observed at stage 1. MRI staging was in coordination with clinical staging in eight of them and for one patient MRI accorded stage 2B (88% concordance). CONCLUSIONS: MRI is a reliable noninvasive method with high accuracy for cervical cancer staging. Also presently it is easily obtainable, so we recommend using this technique along with clinical examination for staging cervical cancer patients. We also recommend to radiologists and residents of radiology to get experience with this method of staging.


Asunto(s)
Examen Ginecologíco , Imagen por Resonancia Magnética/métodos , Estadificación de Neoplasias , Neoplasias del Cuello Uterino/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Persona de Mediana Edad , Prueba de Papanicolaou , Estudios Prospectivos , Neoplasias del Cuello Uterino/patología , Frotis Vaginal
5.
Exp Clin Transplant ; 10(6): 568-72, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23216565

RESUMEN

OBJECTIVES: There are conflicting data regarding the use of some measured indices by Doppler ultrasound such as the resistive index and the pulsatility index in predicting renal allograft dysfunction. This study sought to evaluate the association of early postoperative Doppler indices and 3-month serum creatinine levels in renal transplant recipients. MATERIALS AND METHODS: During a 1-year period, all patients who underwent renal transplant at our hospital were recruited into a prospective study. Doppler ultrasound was performed on all patients 6 days and 3 months after the transplant and the resistive index and the pulsatility index were calculated for each patient. Then, the association between these indices and 3-month outcomes of patients were investigated. RESULTS: Thirty-eight patients including 21 men (mean age, 36.6 ± 13.1 y) were evaluated. There was a positive correlation between the resistive index and the pulsatility index at 6 days after transplant and the serum creatinine measured at the same day (P < .001 and r=0.570 for resistive index; P < .001 and r=0.547 for pulsatility index). There was also a positive correlation between the pulsatility index and the resistive index at 6 days after transplant and 3-month serum creatinine level (P = .009 and r=0.420 for resistive index; P = .009 and r=0.417 for pulsatility index). There were negative correlations between the resistive index and the pulsatility index on the sixth day after surgery and creatinine clearance measured at 6 days and 3 months after transplant. CONCLUSIONS: This study reveals a strong-to-medium correlation between the resistive index and the pulsatility index, serum creatinine level, measured 6 days after transplant.


Asunto(s)
Creatinina/sangre , Trasplante de Riñón , Riñón/diagnóstico por imagen , Adulto , Ecocardiografía Doppler , Femenino , Humanos , Trasplante de Riñón/diagnóstico por imagen , Masculino , Estudios Prospectivos
6.
Hematol Rep ; 4(2): e7, 2012 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-22826797

RESUMEN

The presence of apparently normal hematopoietic tissue outside of bone marrow cavity is defined as extramedullary hematopoiesis (EMH). EMH is a rare complication in thalassemia major (TM) and adrenal gland as well. This report describes a case of adrenal EMH in a 26-year-old man with ß-TM. He has been transfused with regular blood transfusion since 9 months. During the routine physical examination he was incidentally found to have a hypoechoic mass at his abdominal ultrasonography. Abdominal computed tomography scan revealed a right well-defined suprarenal mass 7.7×7.3×5.8 cm in size. The diagnosis of EMH was confirmed with ultrasonographic-guided fine needle biopsy. Treatment options which include intensified regular blood transfusion and hydroxyurea have been started.

7.
J Med Case Rep ; 5: 274, 2011 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-21722393

RESUMEN

INTRODUCTION: Iliopsoas hemorrhage is a serious complication of bleeding disorders that occurs most commonly in patients with hemophilia and less commonly in patients with von Willebrand disease. It causes severe pain, muscle dysfunction and occasionally femoral nerve palsy. We describe the case of a patient with von Willebrand disease type 3 with a large iliopsoas hematoma who was treated with a von Willebrand factor concentrate (Humate-P). CASE PRESENTATION: A 20-year-old Iranian man was referred to our emergency ward because of the gradual onset of right flank pain. He was known to have been diagnosed with von Willebrand disease type 3 at age two years old. Magnetic resonance imaging showed a mass in the right iliopsoas muscle. The diagnosis of iliopsoas hemorrhage and partial femoral nerve palsy was established, and he responded to medical treatment. CONCLUSION: We report a case of von Willebrand disease type 3 with spontaneous iliopsoas hematoma associated with femoral nerve palsy that was well managed with Humate-P treatment.

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