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1.
Asian Spine J ; 16(6): 934-946, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36573301

RESUMEN

A vertebral fracture is the most common type of osteoporotic fracture. Osteoporotic vertebral fractures (OVFs) cause a variety of morbidities and deaths. There are currently few "gold standard treatments" outlined for the management of OVFs in terms of quantity and quality. Conservative treatment is the primary treatment option for OVFs. The treatment of pain includes short-term bed rest, analgesic medication, anti-osteoporotic medications, exercise, and a brace. Numerous reports have been made on studies for vertebral augmentation (VA), including vertebroplasty and kyphoplasty. There is still debate and controversy about the effectiveness of VA in comparison with conservative treatment. Until more robust data are available, current evidence does not support the routine use of VA for OVF. Despite the fact that the majority of OVFs heal without surgery, 15%-35% of patients with an unstable fracture, persistent intractable back pain, or severely collapsed vertebra that causes a neurologic deficit, kyphosis, or chronic pseudarthrosis frequently require surgery. Because no single approach can guarantee the best surgical outcomes, customized surgical techniques are required. Surgeons must stay current on developments in the osteoporotic spine field and be open to new treatment options. Osteoporosis management and prevention are critical to lowering the risk of future OVFs. Clinical studies on bisphosphonate's effects on fracture healing are lacking. Teriparatide was intermittently administered, which dramatically improved spinal fusion and fracture healing while lowering mortality risk. According to the available literature, there are no standard management methods for OVFs. More multimodal approaches, including conservative and surgical treatment, VA, and medications that treat osteoporosis and promote fracture healing, are required to improve the quality of the majority of guidelines.

2.
Materials (Basel) ; 15(18)2022 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-36143679

RESUMEN

Enhancement in the efficiency of a TiO2 dye-sensitized solar cell (DSSC) has been demonstrated by introducing ferromagnetic perovskite BiFeO3 and controlling the magnetic field, which induces two-dimensional material-like properties in the bulk of the TiO2-BiFeO3 DSSC (a 3-dimensional material). The effect of the concentration of BiFeO3 as well as the magnetization direction on the performance of the TiO2-BiFeO3 DSSC has been investigated. After magnetization, it was confirmed that the current density, efficiency, and open circuit voltage of the TiO2-BiFeO3 DSSC were increased. The observed phenomena have been explained in terms of the Hall effect which is responsible for the reduction of the degree of freedom of the electron movement resulting in the two-dimensional material-like properties in the bulk of the TiO2-BiFeO3 DSSC.

3.
Cancers (Basel) ; 14(12)2022 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-35740553

RESUMEN

The feasibility of proton minibeam radiation therapy (pMBRT) using a multislit collimator (MSC) and a scattering device was evaluated for clinical use at a clinical proton therapy facility. We fabricated, through Monte Carlo (MC) simulations, not only an MSC with a high peak-to-valley dose ratio (PVDR) at the entrance of the proton beam, to prevent radiation toxicity, but also a scattering device to modulate the PVDR in depth. The slit width and center-to-center distance of the diverging MSC were 2.5 mm and 5.0 mm at the large end, respectively, and its thickness and available field size were 100 mm and 76 × 77.5 mm2, respectively. Spatially fractionated dose distributions were measured at various depths using radiochromic EBT3 films and also tested on bacterial cells. MC simulation showed that the thicker the MSC, the higher the PVDR at the phantom surface. Dosimetric evaluations showed that lateral dose profiles varied according to the scatterer's thickness, and the depths satisfying PVDR = 1.1 moved toward the surface as their thickness increased. The response of the bacterial cells to the proton minibeams' depth was also established, in a manner similar to the dosimetric pattern. Conclusively, these results strongly suggest that pMBRT can be implemented in clinical centers by using MSC and scatterers.

4.
J Toxicol Pathol ; 35(1): 45-52, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35221495

RESUMEN

Platycodi radix is widely used in traditional herbal medicine for the treatment of bronchitis, asthma, pulmonary tuberculosis, hypertension, hyperlipidemia, and diabetes. This study aimed to investigate cell proliferation (Ki-67) and apoptosis (Caspase-3) potential in squamous cell hyperplasia of the stomach induced by a Platycodi radix water extract in a subchronic toxicity study. One hundred formalin-fixed, paraffin-embedded stomach tissues of rats treated with Platycodi radix at doses of 0, 500, 1,000, and 3,000 mg/kg body weight/day were used for the analysis. They were conventionally stained using hematoxylin and eosin (H&E) and immunohistochemically (IHC) stained using caspase-3 and Ki-67 antibodies. The incidence of squamous cell hyperplasia was significantly increased in the 3,000 mg/kg b.w./day treatment group in both sexes (p<0.01). However, the hyperplastic change was completely repaired after 4 weeks of recovery period. Ki-67 expression was similar in all groups, with no statistically significant differences among the groups. Caspase-3 expression was significantly increased in both sexes in the 3,000 mg/kg b.w./day treatment group (p<0.01), compared with the vehicle control groups, and then reduced to normal levels in the recovery groups in both sexes. In conclusion, this study showed that squamous cell hyperplasia induced by the Platycodi radix water extract in the limiting ridge of the stomach is not considered to be abnormal proliferative change; as a result, squamous cell hyperplasia is considered to be a non-adverse effect when induced by the oral administration of the Platycodi radix water extract once daily for 13 weeks in rats.

5.
Jpn J Clin Oncol ; 52(3): 266-273, 2022 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-34958091

RESUMEN

OBJECTIVE: To propose and evaluate an active method for sparing the small bowel in the treatment field of cervical cancer brachytherapy by prone position procedure. METHODS: The prone position procedure consists of five steps: making bladder empty, prone-positioning a patient on belly board, making the small bowel move to abdomen, filling the bladder with Foley catheter and finally turning the patient into the supine position. The proposed method was applied for the treatment of seven cervical cancer patients. Its effectiveness was evaluated and a correlation between the patient characteristics and the volumetric dose reduction of small bowel was also investigated. Brachytherapy treatment plans were built before and after the proposed method, and their dose-volume histograms were compared for targets and organs-at-risk. In this comparison, all plans were normalized to satisfy the same D90% for high-risk clinical target volume. RESULTS: For the enrolled patients, the average dose of small bowel was significantly reduced from 75.2 ± 4.9 Gy before to 60.2 ± 4.0 Gy after the prone position procedure, while minor dosimetric changes were observed in rectum, sigmoid and bladder. The linear correlation to body mass index, thickness and width of abdominopelvic cavity and bladder volume were 76.2, 69.7, 28.8 and -36.3%, respectively. CONCLUSIONS: The application of prone position procedure could effectively lower the volumetric dose of the small bowel. The dose reduction in the small bowel had a strong correlation with the patient's obesity and abdominal thickness. This means the patients for whom the proposed method would be beneficial can be judiciously selected for safe brachytherapy.


Asunto(s)
Braquiterapia , Neoplasias del Cuello Uterino , Abdomen , Braquiterapia/métodos , Femenino , Humanos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Recto , Neoplasias del Cuello Uterino/radioterapia
6.
Facial Plast Surg Clin North Am ; 29(4): 487-495, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34579832

RESUMEN

Asians have anatomic and clinical characteristics to be considered before forehead lift. Because of the anatomic characteristics of Asians, for the better outcomes of blepharoplasty or augmentation rhinoplasty, forehead lift as a combined surgery must be considered beforehand. Forehead lift is frequently indicated in young Asian patients. Endoscopic browlift without visible scar is favored for patients, and it can be done in a modified multiplane fashion for better outcomes in patients with thick and redundant skin. There are rare but severe complications of endoscopic forehead lift, such as motor nerve paresis and diplopia, although they are temporary in most cases.


Asunto(s)
Blefaroplastia , Ritidoplastia , Pueblo Asiatico , Párpados/cirugía , Frente/cirugía , Humanos
7.
Nanotechnology ; 32(50)2021 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-34500445

RESUMEN

The quantum confinement effect and interesting optical properties of cesium lead halide (CsPbX3; X = Cl, Br, I) perovskite quantum dots (QDs) and nanocrystals (NCs) have given a new horizon to lighting and photonic applications. Given the exponential rate at which scientific results on CsPbX3NCs are published in the last few years, it can be expected that the research in CsPbX3NCs will further receive increasing scientific interests in the near future and possibly lead to great commercial opportunities to realize these materials based practical applications. With the rapid progress in the single-photon emitting CsPbX3QDs and NCs, practical applications of the quantum technologies such as single-photon emitting light-emitting diode, quantum lasers, quantum computing might soon be possible. But to reach at cutting edge of stable perovskite QDs/NCs, the study of fundamental insight and theoretical aspects of crystal design is yet insufficient. Even more, it has aroused many unanswered questions related to the stability, optical and electronic properties of the CsPbX3QDs. Aim of the present review is to illustrate didactically a precise study of recent progress in the synthesis, properties and applications of CsPbX3QDs and NCs. Critical issues that currently restrict the applicability of these QDs will be identified and advanced methodologies currently in the developing queue, to overcome the roadblock, will be presented. And finally, the prospects for future directions will be provided.

8.
Regul Toxicol Pharmacol ; 120: 104844, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33359266

RESUMEN

Dioscorea Rhizome is widely used as a traditional herbal medicine to treat asthma, diarrhea, cough, bronchitis, spermatorrhea, leukorrhea, and rheumatoid arthritis. This study investigated the potential subchronic toxicity of a D. Rhizome water extract (DRWE) after repeated oral administration at 0, 800, 2000, and 5000 mg/kg/day in rats for 13 weeks. During the study period, clinical signs, mortality, body weight, food consumption, water consumption, urinalysis, ophthalmoscopy, hematology, serum biochemistry, gross pathology, organ weights, and histopathology were examined. The 13-week repeated oral administration of DRWE to rats resulted in an increased incidence of zona glomerulosa hypertrophy and hyperplasia in the adrenal gland at dose levels of ≥2000 mg/kg/day in both sexes. However, these findings are considered as non-adverse adaptive changes because of minimal histological changes in the lesions, which were not accompanied by any corresponding alterations in serum electrolytes and adrenal gland weight. No treatment-related adverse effects on clinical signs, body weight, food and water consumption, ophthalmic examination, urinalysis, hematology, serum biochemistry, necropsy findings, and organ weights were observed at any dose tested. Under the present experimental conditions, the no-observed-adverse-effect level of the DRWE was considered to be 5000 mg/kg/day in both sexes, and no target organs were identified.


Asunto(s)
Dioscorea/toxicidad , Extractos Vegetales/toxicidad , Rizoma/toxicidad , Pruebas de Toxicidad Subcrónica/métodos , Agua , Animales , Peso Corporal/efectos de los fármacos , Peso Corporal/fisiología , Femenino , Masculino , Nivel sin Efectos Adversos Observados , Tamaño de los Órganos/efectos de los fármacos , Tamaño de los Órganos/fisiología , Extractos Vegetales/aislamiento & purificación , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
9.
PLoS One ; 15(12): e0242966, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33264363

RESUMEN

We evaluate the ocular effects of proton beam therapy (PBT) in a single institution, in Korea, and identify factors contributing to decreasing visual acuity (VA) after PBT. A total of 40 patients who received PBT for choroidal melanoma (2009‒2016) were reviewed. Dose fractionation was 60‒70 cobalt gray equivalents (CGEs) over five fractions. Complete ophthalmic examinations including funduscopy and ultrasonography were performed at baseline and at 3, 6, and 12 months after PBT, then annually thereafter. Only patients with at least 12 months follow-up were included. During the follow-up, consecutive best-corrected visual acuity (BCVA) changes were determined, and univariate and multivariate logistic regression analyses were performed to identify predictors for VA loss. The median follow-up duration was 32 months (range: 12‒82 months). The final BCVA of nine patients was > 20/40. The main cause of vision loss was intraocular bleeding, such as neovascular glaucoma or retinal hemorrhage. Vision loss was correlated with the tumor size, tumor distance to the optic disc or fovea, maculae receiving 30 CGEs, optic discs receiving 30 CGEs, and retinas receiving 30 CGEs. Approximately one-third of PBT-treated choroidal melanoma patients with good pretreatment BCVA maintained their VA. The patients who finally lost vision (VA < count fingers) usually experienced rapid declines in VA from 6‒12 months after PBT. Tumor size, tumor distance to the optic disc or fovea, volume of the macula, and optic discs or retinas receiving 30 CGEs affected the final VA.


Asunto(s)
Neoplasias de la Coroides/radioterapia , Terapia de Protones , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Coroides/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recuperación de la Función/efectos de la radiación , República de Corea , Estudios Retrospectivos , Resultado del Tratamiento
10.
Medicine (Baltimore) ; 99(22): e20219, 2020 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-32481387

RESUMEN

INTRODUCTION: Enchondromas arise from cartilaginous cells derived from the physis that persists throughout development. They are difficult to diagnose and are often discovered on radiographs after a trauma. PATIENT CONCERNS: We discuss the case of a 32-year-old woman with a pathologic mallet fracture of the distal phalanx that was initially misdiagnosed as common mallet fracture. DIAGNOSIS: Magnetic resonance imaging revealed an eccentrically located lesion expanding to the cortex, with a high signal intensity at T2 weighted image, suggesting pathologic fracture. INTERVENTIONS: We performed a operation, involving curettage and bone grafting. Complete removal of the lesion was confirmed intraoperatively with the image intensifier, and the cavity was irrigated and subsequently filled with allogenous bone and demineralized bone matrix. OUTCOMES: With an uneventful recovery, she gradually return to normal function within 3 months. Her symptoms improved and nearly full range of motion of the finger was seen at 1-year follow-up. CONCLUSION: Our case of pathologic mallet fracture was misdiagnosed as a simple fracture, suggesting that the mechanism of fracture and radiological diagnosis should be carefully considered.


Asunto(s)
Condroma/complicaciones , Condroma/diagnóstico por imagen , Errores Diagnósticos , Falanges de los Dedos de la Mano/diagnóstico por imagen , Fracturas Espontáneas/diagnóstico por imagen , Fracturas Espontáneas/etiología , Adulto , Femenino , Falanges de los Dedos de la Mano/lesiones , Humanos , Imagen por Resonancia Magnética
11.
Nanotechnology ; 31(24): 244001, 2020 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-32084657

RESUMEN

Nanomaterials are the subject of extensive investigations due to their applications in medicine, multimodal imaging, volumetric displays, and photonics. Here, lanthanide-doped bismuth vanadate (BiVO4) upconverting nanoparticles (UCNPs) have been reported. The nanoparticles have been synthesized by a microwave hydrothermal method. As-synthesized nanoparticles are highly crystalline in the tetragonal zircon phase with particles about 200 nm in size. Under 980 nm excitation, intense multicolor visible and near-infrared upconversion emissions are observed. Moreover, broadband infrared downshifting emissions are also observed. Time-resolved emission measurements have been carried out to investigate the involved upconversion and energy transfer mechanism. The BiVO4-based UCNPs may provide a new class of nanomaterials for multifunctional applications.

12.
Endosc Int Open ; 7(12): E1748-E1754, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31828212

RESUMEN

Background and aims The family of serrated polyps (SP) includes hyperplastic polyps (HP), sessile serrated adenomas/polyps, and traditional serrated adenoma. We investigated whether SP synchronous with adenoma at index colonoscopy is associated with metachronous advanced colorectal neoplasia (CRN). Methods Patients with ≥ 1 adenoma on index colonoscopy and who had undergone a follow-up colonoscopy were included. The patients were divided into four groups according to the presence of SP and advanced adenoma (AA) on index colonoscopy (non-AA, non-AA + SP, AA, AA + SP). The cumulative incidence of metachronous advanced CRN at surveillance colonoscopy was compared between groups. Results Among a total of 2209 patients, the numbers of patients in the non-AA, non-AA + SP, AA, and AA + SP groups were 922, 441, 625, and 221, respectively. The cumulative incidence of metachronous advanced CRN was higher in patients in the AA + SP group than that in the AA group ( P <0.001), and there was no significant difference between the non-AA + SP group and the non-AA group ( P  = 0.06). The cumulative incidence of metachronous advanced CRN at 3 years was 17.9 % [95 % confidence interval (CI) 8.0-27.6], 10.7 % [95 %CI 7.7-3.6], 3.5 % [95 %CI 1.3-5.6], and 3.4 % [95 %CI 2.0-4.7] in the AA + SP, AA, non-AA + SP, and non-AA group, respectively. In a multivariate analysis, overall SP [hazard ratio (HR) 2.24; 95 %CI 1.38-3.64, P  = 0.001], proximal SP (HR 2.31; 95 %CI 1.32-4.08), and HP (HR 2.19; 95 %CI 1.35-3.57) were risk factors for metachronous advanced CRN in patients with AA on index colonoscopy. Conclusions Coexistent AA and SP on index colonoscopy significantly increased the risk of metachronous advanced CRN compared with AA alone. Further large prospective studies are needed to confirm whether more intensive follow-up improves outcomes in these high risk patients.

13.
Kidney Res Clin Pract ; 38(4): 517-524, 2019 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-31826389

RESUMEN

BACKGROUND: Previous studies have recommended a 2- to 5-year waiting time prior to kidney transplantation (KT) in patients with end-stage renal disease (ESRD) and symptomatic renal cell carcinoma (RCC) and no delay for incidental early-stage RCC. Data on Asian KT recipients are unavailable. METHODS: This is a Korean single-center retrospective study on 35 KT recipients with ESRD and RCC. Patients were classified into two groups: early KT (KT performed within 1 year after nephrectomy for RCC, including KT with simultaneous nephrectomy) and delayed KT (KT performed over than 1 year after nephrectomy for RCC). Patient survival, graft survival, and cancer recurrence were compared between both groups. RESULTS: There were no statistically significant differences in patient survival (P = 0.388), graft survival (P = 0.317), or graft rejection rate (P = 0.207) between the early and delayed KT groups. Additionally, there were no differences in pathological characteristics or RCC stage other than cancer histology: acquired cystic disease-associated RCC (47.4%) was the most common RCC type in the early KT group, whereas clear cell type (62.5%) was the most common RCC type in the delayed KT group. No RCC recurrence was observed. CONCLUSION: Patients with early-stage and asymptomatic RCC do not require a mandatory observational period prior to KT after curative nephrectomy.

14.
Medicine (Baltimore) ; 98(5): e14311, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30702607

RESUMEN

RATIONALE: Stress fractures are most commonly sustained in the lower extremities owing to the repetitive weight-bearing forces. They are overuse injuries that are seen often in athletes, but rare in the general population, so early diagnosis and proper treatment are important to enable athletes to return to activity. This is a rare example of successful treatment of a medial malleolar stress fracture with lateral ankle instability. PATIENT CONCERNS: A 16-year-old athlete presented with acute-onset left ankle pain. He was a baseball pitcher who had previously sprained left ankle while training. Subsequently, the ankle pain worsened, and he had tenderness on the medial aspect of his left ankle. The symptoms were mild at rest, but increased upon walking and training. Three years previously, he had sprained his ankle several times during baseball training. DIAGNOSIS: Plain standing radiographs of the left ankle showed a vertical fracture line in the medial malleolus. Computed tomography also showed the vertical fracture in the medial malleolus. Magnetic resonance imaging revealed mild bone marrow edema in the medial malleolar area and total rupture of the anterior talofibular ligament. INTERVENTIONS: Surgery was performed under general anesthesia, and we checked the instability of his ankle using a C-arm image intensifier, and the varus talar tilt angle was increased (10.3°). The medial malleolus stress fracture was fixed using tension bend wiring, and an arthroscopic modified Broström procedure was done. OUTCOMES: Two months postoperatively, the patient started walking, and raised-heel squatting. The medial malleolar fracture was completely united at the 3 months postoperatively on plain radiography, and return to full activity was achieved by 3 months postoperatively. Then the hardware was removed 1-year after operation and both the anterior drawer and external rotation stress tests were negative. LESSONS: Medial malleolar stress fractures are rare, so they can be overlooked. With these fractures, plain radiographs are frequently normal initially because the medial malleolus consists mainly of cancellous bone. Physicians require a high level of suspicion when taking the patient's history and doing the physical examination. Because most occur in athletes, early diagnosis and proper treatment are important for patients' subsequent athletic performance.


Asunto(s)
Fracturas de Tobillo/diagnóstico , Fracturas de Tobillo/etiología , Articulación del Tobillo , Fracturas por Estrés/diagnóstico , Fracturas por Estrés/etiología , Inestabilidad de la Articulación/complicaciones , Adolescente , Fracturas de Tobillo/cirugía , Fracturas por Estrés/cirugía , Humanos , Masculino
15.
Arthroscopy ; 35(3): 953-960, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30611585

RESUMEN

PURPOSE: To evaluate the clinical and radiological outcomes of the all-inside, arthroscopic, modified Broström procedure (MBP) used to treat chronic lateral ankle instability (CLAI) according to subfibular ossicle (SFO) status. METHODS: Between January 2013 and September 2016, we retrospectively analyzed CLAI patients who underwent the arthroscopic MBP. When performing the arthroscopic MBP, SFO was removed with all inside technique regardless of size. Patients who were not followed for more than a minimum of 12 months after surgery were excluded. The patients were divided into 2 groups: ankles with SFOs were assigned to the SFO group and the others to the non-SFO (NSFO) group. The evaluation tools used included the American Orthopedic Foot and Ankle Society (AOFAS) ankle-hind foot score, a pain visual analog scale, and the talar tilt angle. RESULTS: Following the inclusion criteria, we included 125 patients (125 ankles) in this study. The SFO group consisted of 26 patients and the NSFO group consisted of 99 patients. The preoperative scores in the 2 groups shows no significant difference except for AOFAS scores. The final AOFAS scores in both groups improved compared with the preoperative scores (18.4 ± 16.3 and 22.1 ± 21.6 for the SFO and NSFO groups, respectively). The final follow-up visual analog scale scores also improved in both groups (5.0 ± 1.7 and 5.2 ± 1.4, respectively). The mean ± standard deviation talar tilt improved from 8.7 ± 5.0° preoperatively to 4.6 ± 3.6° at the final follow-up in the SFO group, and from 7.3 ± 4.4° preoperatively to 3.2 ± 3.0° at the final follow-up in the NSFO group. Neither the preoperative nor final talar tilt angle differed between the 2 groups (P = .300 and P = .072, respectively). CONCLUSIONS: All-inside arthroscopic MBP after SFO resection was as successful as the same surgery without SFO resection. The clinical outcomes of the SFO and NSFO groups did not differ. Both groups achieved successful radiological outcomes at the last follow-up. All-inside arthroscopic MBP is a reliable treatment for CLAI patients regardless of SFO status. LEVEL OF EVIDENCE: Level III, retrospective comparative study.


Asunto(s)
Articulación del Tobillo/cirugía , Artroscopía/métodos , Inestabilidad de la Articulación/cirugía , Procedimientos Ortopédicos/métodos , Adulto , Articulación del Tobillo/patología , Enfermedad Crónica , Femenino , Humanos , Inestabilidad de la Articulación/diagnóstico por imagen , Inestabilidad de la Articulación/patología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Escala Visual Analógica , Adulto Joven
16.
Nanotechnology ; 29(20): 204004, 2018 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-29488468

RESUMEN

Yb3+ and Er3+ doped YVO4 (Yb3+/Er3+:YVO4) nanoparticles with highly efficient near-infrared to visible upconversion properties have been synthesized by microwave hydrothermal process. Uniform-sized Yb3+/Er3+:YVO4 nanoparticles were synthesized within 1 h at 140 °C which is relatively faster than the conventional hydrothermal process. Under 980 nm laser excitation, strong green and less strong red emissions are observed which are attributed to 2H11/2, 4S3/2 to 4I15/2 and 4F9/2 to 4I15/2 transitions of Er3+ respectively. The emission intensity is found to depend strongly on the concentration of Yb3+. The quadratic dependence of upconversion intensity on the excitation power indicates that the upconversion process is governed by two-photon absorption process.

17.
Case Rep Gastroenterol ; 11(3): 559-563, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29033778

RESUMEN

Basaloid squamous cell carcinoma of the esophagus is very rare. Further, polypoid type of esophageal cancer is also rare. We have recently treated a case of basaloid squamous cell carcinoma which presented as a 1.3-cm esophageal polyp. A 48-year-old woman was referred to our hospital because of a polypoid mass at 36 cm distance from the upper incisor on endoscopic examination, and the result of the biopsy was basaloid squamous cell carcinoma. The patient underwent Ivor Lewis operation with lymph node dissection. Two basaloid squamous cell carcinomas, of 1.3 and 0.4 cm, were diagnosed in the final pathologic examination. Regular periodic follow-up showed no evidence of recurrence or metastasis in the 5-month postoperative period.

18.
Phys Med Biol ; 62(19): 7598-7616, 2017 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-28809759

RESUMEN

For the independent validation of treatment plans, we developed a fully automated Monte Carlo (MC)-based patient dose calculation system with the tool for particle simulation (TOPAS) and proton therapy machine installed at the National Cancer Center in Korea to enable routine and automatic dose recalculation for each patient. The proton beam nozzle was modeled with TOPAS to simulate the therapeutic beam, and MC commissioning was performed by comparing percent depth dose with the measurement. The beam set-up based on the prescribed beam range and modulation width was automated by modifying the vendor-specific method. The CT phantom was modeled based on the DICOM CT files with TOPAS-built-in function, and an in-house-developed C++ code directly imports the CT files for positioning the CT phantom, RT-plan file for simulating the treatment plan, and RT-structure file for applying the Hounsfield unit (HU) assignment, respectively. The developed system was validated by comparing the dose distributions with those calculated by the treatment planning system (TPS) for a lung phantom and two patient cases of abdomen and internal mammary node. The results of the beam commissioning were in good agreement of up to 0.8 mm2 [Formula: see text] for B8 option in both of the beam range and the modulation width of the spread-out Bragg peaks. The beam set-up technique can predict the range and modulation width with an accuracy of 0.06% and 0.51%, respectively, with respect to the prescribed range and modulation in arbitrary points of B5 option (128.3, 132.0, and 141.2 mm2 [Formula: see text] of range). The dose distributions showed higher than 99% passing rate for the 3D gamma index (3 mm distance to agreement and 3% dose difference) between the MC simulations and the clinical TPS in the target volume. However, in the normal tissues, less favorable agreements were obtained for the radiation treatment planning with the lung phantom and internal mammary node cases. The discrepancies might come from the limitations of the clinical TPS, which is the inaccurate dose calculation algorithm for the scattering effect, in the range compensator and inhomogeneous material. Moreover, the steep slope of the compensator, conversion of the HU values to the human phantom, and the dose calculation algorithm for the HU assignment also could be reasons of the discrepancies. The current study could be used for the independent dose validation of treatment plans including high inhomogeneities, the steep compensator, and riskiness such as lung, head & neck cases. According to the treatment policy, the dose discrepancies predicted with MC could be used for the acceptance decision of the original treatment plan.


Asunto(s)
Pulmón/efectos de la radiación , Método de Montecarlo , Fantasmas de Imagen , Terapia de Protones/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Dispersión de Radiación , Algoritmos , Humanos , Dosificación Radioterapéutica
19.
Korean J Gastroenterol ; 69(6): 333-340, 2017 Jun 25.
Artículo en Coreano | MEDLINE | ID: mdl-28637101

RESUMEN

Non-alcoholic fatty liver disease (NAFLD) includes a wide spectrum of diseases that range from simple steatosis to non-alcoholic steatohepatitis (NASH) and cirrhosis. In addition, the burden of NAFLD is rapidly growing. Previously, NAFLD was regarded as a hepatic manifestation of metabolic syndrome, which is a traditional cardiovascular disease (CVD) risk factor. However, there has been an increasing evidence that suggest NAFLD to be an independent risk factor of CVD. Therefore, currently, NAFLD should be reconsidered as not only a simple manifestation of metabolic syndrome, but also a systemic disease that contribute to CVD. There are some reasonable hypotheses about the relationship between NAFLD and CVD. Moreover, many studies have been performed to better understand this relationship. Nonetheless, the underlying mechanisms and pathogenesis of NAFLD that contribute to CVD have not yet been fully elucidated to date. This review focuses on the underlying mechanisms and relationship between NAFLD and CVD.


Asunto(s)
Enfermedades Cardiovasculares/diagnóstico , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Citocinas/metabolismo , Proteína HMGB1/metabolismo , Homocisteína/sangre , Humanos , Resistencia a la Insulina , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Factores de Riesgo , Factor A de Crecimiento Endotelial Vascular/metabolismo , alfa-2-Glicoproteína-HS/metabolismo
20.
Toxicol Res ; 33(2): 141-147, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28503263

RESUMEN

Peripheral ameloblastic odontoma is a rare variant of odontogenic tumor occurring in the extraosseous region. The present report describes a spontaneous tumor in male Sprague-Dawley (SD) rats. The clinically confirmed nodule in the right mandibular region was first observed when the rat was 42 weeks and remained until the terminal sacrifice date when the animal was 48 weeks of age. At necropsy, a well demarcated nodule, approximately 2.5 × 2.0 × 2.0 cm, protruded from the ventral area of the right mandible. The nodule was not attached to mandibular bone and was not continuous with the normal teeth. Histopathologically, the tumor was characterized by the simultaneous occurrence of an ameloblastomatous component and composite odontoma-like elements within the same tumor. The epithelial portion formed islands or cords resembling the follicle or plexiform pattern typical of ameloblastoma and was surrounded by mesenchymal tissue. Formation of eosinophilic and basophilic hard tissue matrix (dentin and enamel) resembling odontoma was observed in the center of the tumor. Mitotic figures were rare, and areas of cystic degeneration were present. Immunohistochemically, the epithelial component was positive for cytokeratin AE1/AE3 (CK AE1/AE3), and the mesenchymal component and odontoblast-like cells were positive for vimentin, in the same manner as in normal teeth. On the basis of these findings, the tumor was diagnosed as a peripheral ameloblastic odontoma in an extraosseous mandibular region in a SD rat. In the present study, we report the uncommon spontaneous peripheral ameloblastic odontoma in the SD rat. We also discuss here the morphological characteristics, origin, histochemical, and immunohistochemical features for the diagnosis of this tumor.

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