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1.
Cryo Letters ; 44(1): 37-46, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36629840

RESUMO

BACKGROUND: Successful cryopreservation of bovine oocytes is very important for research and commercial applications. However, the survival and development rate of vitrified-thawed (VT) oocytes are lower than those of non-vitrified-thawed (non-VT) oocytes. OBJECTIVE: To investigate the effect of adding hydroxypropyl cellulose (HPC) to the vitrification solution for bovine oocytes. MATERIALS AND METHODS: For vitrification, bovine metaphase II oocytes were pretreated with a solution containing 10% ethylene glycol supplemented with 0, 10, 50, or 100 ug/mL HPC for 5 min, exposed to a solution containing 30% ethylene glycol supplemented with 0, 10, 50, or 100 ug/mL HPC for 30 s, and then directly plunged into liquid nitrogen. RESULTS: The survival rate of oocytes was significantly higher in the 50 HPC group than in the 0, 10, and 100 HPC groups. The reactive oxygen species level was lower in the non-VT and 50 HPC groups than in the other groups. The mRNA levels of proapoptotic genes (Bax) were lower in the non-VT, 0, and 50 HPC groups than in the other groups. The mRNA levels of antiapoptotic genes (BCl2) were higher in the non-VT than in the other groups. The development rates of embryos (day 8) obtained via parthenogenetic activation (PA) were determined in the non-VT, 0 HPC, and 50 HPC groups. The cleavage rate was significantly higher in the non-VT group. CONCLUSION: Supplementation of vitrification solution with HPC improves the survival of VT bovine oocytes and the development capacity of embryos derived from these oocytes via PA. doi.org/10.54680/fr23110110212.


Assuntos
Criopreservação , Vitrificação , Animais , Bovinos , Criopreservação/veterinária , Oócitos/fisiologia , Crioprotetores/farmacologia , Suplementos Nutricionais , Etilenoglicóis/farmacologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-31186605

RESUMO

With the improving energy resolution of transitionedge sensor (TES) based microcalorimeters, performance verification and calibration of these detectors has become increasingly challenging, especially in the energy range below 1 keV where fluorescent atomic X-ray lines have linewidths that are wider than the detector energy resolution and require impractically high statistics to determine the gain and deconvolve the instrumental profile. Better behaved calibration sources such as grating monochromators are too cumbersome for space missions and are difficult to use in the lab. As an alternative, we are exploring the use of pulses of 3 eV optical photons delivered by an optical fiber to generate combs of known energies with known arrival times. Here, we discuss initial results of this technique obtained with 2 eV and 0.7 eV resolution X-ray microcalorimeters. With the 2 eV detector, we have achieved photon number resolution for pulses with mean photon number up to 133 (corresponding to 0.4 keV).

3.
Ann Oncol ; 29(9): 2010-2017, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30016386

RESUMO

Background: In contrast to its well-known endocrine function, the role of inhibin in cancer development and therapeutic response is unclear. Salmonella, particularly less toxic attenuated Salmonella strains, are used to treat cancer in two ways. First, Salmonella accumulate around tumors, penetrate the cell barrier, and replicate inside the tumors. Second, Salmonella can act as a vehicle for delivering anticancer agents or proapoptotic genes to attack tumors. In this study, we aimed to develop a suitable cancer therapeutic strategy by genetically modifying attenuated Salmonella typhimurium to harbor short hairpin RNA (shRNA) expression plasmids targeting alpha subunit of inhibin (sh-INHA). Methods: We analyzed the expression of human INHA in normal and cancer cells and tissues. We developed genetically engineered attenuated S. typhimurium harboring sh-INHA (S. typhimurium/sh-INHA) and assessed its cancer therapeutic effects by using cell culture models and syngeneic mouse tumor models. Results: INHA expression levels were markedly higher in colon cancer and melanoma cells and tissues than in their normal counterparts. Suppression of INHA expression mildly reduced cancer cell survival and induced caspase activation and downregulation of anti-apoptotic Bcl-2 and Bcl-xL expressions. Although the genetically engineered S. typhimurium mildly interfered with the invasion of S. typhimurium into host colon cancer and melanoma cells, S. typhimurium/sh-INHA caused remarkable cytotoxicity in cancer compared with unmodified S. typhimurium or S. typhimurium expressing a control scrambled shRNA (S. typhimurium/sh-Cont). Salmonella typhimurium/sh-INHA-treated mice also showed a significantly inhibited growth of colon cancers and melanomas, with a survival advantage. Conclusion: Our results suggest that tumor-targeted therapy using S. typhimurium/sh-INHA may provide a novel cancer treatment option.


Assuntos
Neoplasias do Colo/terapia , Terapia Genética/métodos , Inibinas/genética , Melanoma/terapia , RNA Interferente Pequeno/administração & dosagem , Neoplasias Cutâneas/terapia , Animais , Linhagem Celular Tumoral/transplante , Colo/patologia , Neoplasias do Colo/patologia , Modelos Animais de Doenças , Feminino , Técnicas de Silenciamento de Genes , Vetores Genéticos/genética , Humanos , Inibinas/metabolismo , Melanoma/patologia , Camundongos , Plasmídeos/genética , RNA Interferente Pequeno/genética , Salmonella typhimurium/genética , Pele/patologia , Neoplasias Cutâneas/patologia
4.
Nutr Metab Cardiovasc Dis ; 28(1): 14-22, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29191476

RESUMO

BACKGROUND AND AIMS: Intracranial arterial stenosis (ICAS) is one of the most common causes of stroke, especially in Asians. Hyperuricemia has been associated with an increased risk of comorbidities such as metabolic syndrome or cardiovascular diseases. However, there are few studies focusing on the association between serum uric acid (SUA) levels and asymptomatic ICAS. The aim of this study was to explore the association between SUA and the prevalence of ICAS in middle-aged Korean health screening examinees. METHODS AND RESULTS: A cross-sectional study was performed on 9417 males and 7755 females who underwent a comprehensive health examination including transcranial Doppler (TCD) ultrasonography. The association of SUA and ICAS was analyzed using multivariate logistic regression. The prevalence of ICAS among the total examinee population was 3.55%. In females, the multivariate-adjusted odds ratio for ICAS was 1.52 (confidence interval 1.13-2.04) in the 3rd quartile of SUA and 1.45 (1.05-2.00) in the highest quartile, compared to the reference (P for trend 0.008). This trend was evident in all clinically relevant subgroups evaluated, including women with low inflammation status. SUA was not significantly associated with the prevalence of ICAS among males. In a sensitivity analysis, the multivariate-adjusted odds ratio of middle cerebral artery stenosis in females was 1.60 (1.09-2.37) in the highest quartile compared to the reference (P for trend 0.023). CONCLUSIONS: Higher SUA level was associated with increased risk of ICAS among middle-aged females but not males. A further cohort study is warranted to elucidate the effect of SUA on asymptomatic ICAS.


Assuntos
Hiperuricemia/sangue , Doenças Arteriais Intracranianas/sangue , Ácido Úrico/sangue , Adulto , Doenças Assintomáticas , Biomarcadores/sangue , Comorbidade , Estudos Transversais , Feminino , Humanos , Hiperuricemia/diagnóstico , Hiperuricemia/epidemiologia , Doenças Arteriais Intracranianas/diagnóstico por imagem , Doenças Arteriais Intracranianas/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , República da Coreia/epidemiologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Ultrassonografia Doppler Transcraniana
5.
Phys Chem Chem Phys ; 19(11): 7607-7616, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28252119

RESUMO

In this study accelerated ageing testing (AAT), J-V characterization and TEM imaging in combination with phase diagram data from literature are used to assess the potential of Ti, Ni, Pd and Pt as diffusion barriers for Au/Cu-based metallization of III-V solar cells. Ni barriers show the largest potential as at an AAT temperature of 250 °C both cells with 10 and 100 nm thick Ni barriers show significantly better performance compared to Au/Cu cells, with the cells with 10 nm Ni barriers even showing virtually no degradation after 7.5 days at 250 °C (equivalent to 10 years at 100 °C at an Ea of 0.70 eV). Detailed investigation shows that Ni does not act as a barrier in the classical sense, i.e. preventing diffusion of Cu and Au across the barrier. Instead Ni modifies or slows down the interactions taking place during device degradation and thus effectively acts as an 'interaction' barrier. Different interactions occur at temperatures below and above 250 °C and for thin (10 nm) and thick (100 nm) barriers. The results of this study indicate that 10-100 nm thick Ni intermediate layers in the Cu/Au based metallization of III-V solar cells may be beneficial to improve the device stability upon exposure to elevated temperatures.

6.
Eur Spine J ; 26(10): 2589-2597, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28180981

RESUMO

PURPOSE: To investigate whether pre-operative magnetic resonance imaging (MRI) of the lumbar multifidus muscle (LMM) would predict clinical outcomes following lumbar spinal decompression for symptomatic spinal stenosis. METHODS: A prospective cohort of patients with symptomatic neurogenic claudication, documented spinal stenosis on pre-operative MRI underwent spinal decompression. All subjects completed standardised outcome measures (Core Outcome Measures Index (COMI), Oswestry Disability Index (ODI v2.1) pre-operatively, 1 and 2 years post-surgery. Surgery was performed using a standardised lumbar spinous process osteotomy for access, followed by a decompression of the central canal, lateral recess and foraminal zones as indicated by the pre-operative MRI. Lumbar MRI scans were evaluated by two independent observers who assessed the axial CSA of the LMM bilaterally and the degree of muscle atrophy according to the Kader classification (2000). Changes in COMI and ODI scores at 1 and 2 years were investigated for statistically significant correlations with CSA of LMM and Kader grading. Statistical analyses utilised Student's t test, kappa coefficient for inter-observer agreement and Bland-Altman Limits of Agreement (BALOA). RESULTS: 66 patients (41 female) aged between 29 and 86 years underwent single-level decompression in 44, two-level decompression in 16 and three-level decompression in 6 cases. No significant correlation was observed between improvements in ODI and COMI relative to age, degree of stenosis, posterior fat thickness or psoas CSA. Those subjects with the greatest LMM atrophy relative to psoas CSA and L5 vertebral body area on pre-operative MRI had the least absolute improvement in both ODI and COMI scores (p = 0.006). CONCLUSIONS: Reduced LMM CSA (<8.5 cm2) and muscle atrophy were associated with less favourable outcomes following lumbar spinal decompression. Pre-operative CSA of LMM appeared to be a more reliable predictor of post-operative clinical outcomes compared to the Kader Grading Score. This is the first study to investigate the prognostic value of pre-operative MRI appearance and CSA of LMM with respect to post-operative outcome following lumbar decompression surgery. Healthy pre-operative LMM is associated with better outcomes following lumbar spinal decompression.


Assuntos
Descompressão Cirúrgica , Vértebras Lombares/cirurgia , Imageamento por Ressonância Magnética , Músculos Paraespinais/diagnóstico por imagem , Avaliação de Resultados da Assistência ao Paciente , Estenose Espinal/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atrofia Muscular , Músculos Paraespinais/patologia , Período Pré-Operatório
7.
Artigo em Inglês | MEDLINE | ID: mdl-28804229

RESUMO

We are developing superconducting transition-edge sensor (TES) microcalorimeter focal planes for versatility in meeting specifications of X-ray imaging spectrometers including high count-rate, high energy resolution, and large field-of-view. In particular, a focal plane composed of two sub-arrays: one of fine-pitch, high count-rate devices and the other of slower, larger pixels with similar energy resolution, offers promise for the next generation of astrophysics instruments, such as the X-ray Integral Field Unit (X-IFU) instrument on the European Space Agency's Athena mission. We have based the sub-arrays of our current design on successful pixel designs that have been demonstrated separately. Pixels with an all gold X-ray absorber on 50 and 75 micron scales where the Mo/Au TES sits atop a thick metal heatsinking layer have shown high resolution and can accommodate high count-rates. The demonstrated larger pixels use a silicon nitride membrane for thermal isolation, thinner Au and an added bismuth layer in a 250 micron square absorber. To tune the parameters of each sub-array requires merging the fabrication processes of the two detector types. We present the fabrication process for dual production of different X-ray absorbers on the same substrate, thick Au on the small pixels and thinner Au with a Bi capping layer on the larger pixels to tune their heat capacities. The process requires multiple electroplating and etching steps, but the absorbers are defined in a single ion milling step. We demonstrate methods for integrating heatsinking of the two types of pixel into the same focal plane consistent with the requirements for each sub-array, including the limiting of thermal crosstalk. We also discuss fabrication process modifications for tuning the intrinsic transition temperature (Tc) of the bilayers for the different device types through variation of the bilayer thicknesses. The latest results on these "hybrid" arrays will be presented.

9.
Phys Chem Chem Phys ; 18(15): 10232-40, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27020800

RESUMO

Substrate-based GaAs solar cells having a dense Au/Cu front contact grid with 45% surface coverage were exposed to accelerated life testing at temperatures between 200 and 300 °C. TEM analysis of the front contacts was used to gain a better understanding of the degradation process. During accelerated life testing at 200 °C only intermixing of the Au and Cu in the front contact occurs, without any significant influence on the J-V curve of the cells, even after 1320 h (55 days) of accelerated life testing. At temperatures ≥250 °C a recrystallization process occurs in which the metals of the contact and the GaAs front contact layer interact. Once the grainy recrystallized layer starts to approach the window, diffusion via grain boundaries to the window and into the active region of the solar cells occurs, causing a decrease in Voc due to enhanced non-radiative recombination via Cu trap levels introduced in the active region of the solar cell. To be a valid simulation of space conditions the accelerated life testing temperature should be <250 °C in future experiments, in order to avoid recrystallization of the metals with the GaAs contact layer.

10.
Surg Endosc ; 30(6): 2641-8, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26679175

RESUMO

BACKGROUND: The aim of this study was to enhance the visual feedback of surgeons, during robotic surgeries, by designing and developing an actuated 2D imaging probe, which is used in conjunction with the traditional stereoscopic camera of the da Vinci surgical system. The probe provides the surgeon with additional visual cues, overcoming visualization constraints encountered during certain scenarios of robot-assisted minimally invasive surgery. METHODS: The actuated imaging probe is implemented as a master-slave tele-manipulated system, and it is designed to be compatible with the da Vinci surgical system. The detachable probe design enables it to be mounted on any of the EndoWrist(®) instruments of the robot and is controlled by the surgeon using a custom-made pedal system. The image from the 2D probe is rendered along with the stereoscopic view on the surgeon's console. RESULTS: The experimental results demonstrate the effectiveness of the proposed actuated imaging probe when used as an additional visualization channel and in surgical scenarios presenting visual problems due to tissue occlusion. CONCLUSION: The study shows the potential benefits of an additional actuated imaging probe when used in conjunction with traditional surgical instruments to perform surgical tasks requiring visualization from multiple orientations and workspaces.


Assuntos
Retroalimentação , Procedimentos Cirúrgicos Robóticos/instrumentação , Cirurgia Assistida por Computador/instrumentação , Percepção de Profundidade , Desenho de Equipamento , Humanos , Curva de Aprendizado
11.
Strahlenther Onkol ; 190(1): 94-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24343757

RESUMO

PURPOSE: To determine the variability of patient positioning errors associated with intensity-modulated radiotherapy (IMRT) for prostate cancer and to assess the impact of thermoplastic pelvic immobilization on these errors using kilovoltage (kV) cone-beam computed tomography (CBCT). MATERIALS AND METHODS: From February 2012 to June 2012, the records of 314 IMRT sessions in 19 patients with prostate cancer, performed with or without immobilization at two different facilities in the Korea University Hospital were analyzed. The kV CBCT images were matched to simulation computed tomography (CT) images to determine the simulation-to-treatment variability. The shifts along the x (lateral)-, y (longitudinal)- and z (vertical)-axes were measured, as was the shift in the three dimensional (3D) vector. RESULTS: The measured systematic errors in the immobilized group during treatment were 0.46 ± 1.75 mm along the x-axis, - 0.35 ± 3.83 mm along the y-axis, 0.20 ± 2.75 mm along the z-axis and 4.05 ± 3.02 mm in the 3D vector. Those of nonimmobilized group were - 1.45 ± 7.50 mm along the x-axis, 1.89 ± 5.07 mm along the y-axis, 0.28 ± 3.81 mm along the z-axis and 8.90 ± 4.79 mm in the 3D vector. The group immobilized with pelvic thermoplastics showed reduced interfractional variability along the x- and y-axes and in the 3D vector compared to the nonimmobilized group (p < 0.05). CONCLUSION: IMRT with thermoplastic pelvic immobilization in patients with prostate cancer appears to be useful in stabilizing interfractional variability during the planned treatment course.


Assuntos
Fracionamento da Dose de Radiação , Imobilização/instrumentação , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Radioterapia Conformacional/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Pelve , Plásticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Strahlenther Onkol ; 189(4): 315-20, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23443609

RESUMO

PURPOSE: The aim of this work was to establish a customized strategy for image-guided radiotherapy during whole breast irradiation. Risk factors associated with extensive errors were assessed. METHODS AND MATERIALS: A series of 176 consecutive breasts in 174 patients were retrospectively assessed. Electronic portal images from 914 medial and 807 lateral directions were reviewed. On the basis of the chest wall, the deviations between the simulation and each treatment were measured. The systematic (Σ) and random error (σ) of population, and the planning target volume (PTV) margin (2 Σ + 0.7σ) were calculated for each direction. Extensive set-up errors were defined as the fraction over the PTV margins in any direction. For extensive set-up errors, χ(2) tests and logistic regression analyses were conducted. RESULTS: The medial and lateral PTV margins for the right-left, superior-inferior, and anterior-posterior axes and the rotation of collimator were 2.6 and 2.4 mm, 4.6 and 4.6 mm, and 3.1 and 3.3 mm and 2.8 and 2.9 ° and cut-off values for extensive errors were 3, 5, and 4 mm and 3 °, respectively. In χ(2) tests, tumor in upper outer quadrant (p = 0.012) and chest wall thickness ≥ 2.0 cm (p = 0.003) for medial portals and age group (p = 0.036) for lateral portals were associated with extensive errors. In multivariate tests, the extensive error on the initial fraction had a high probability of extensive set-up errors in both medial (OR = 4.26, p < 0.001) and lateral portals (OR = 3.07, p < 0.001). CONCLUSION: In terms of the set-up uncertainty during breast irradiation, patients with extensive error in the initial treatment should be closely observed with serial image-guided radiotherapy.


Assuntos
Neoplasias da Mama/radioterapia , Fracionamento da Dose de Radiação , Aceleradores de Partículas , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Adulto , Idoso , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Terapia Combinada , Simulação por Computador , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imobilização/métodos , Mastectomia Segmentar , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Posicionamento do Paciente/métodos , Dosagem Radioterapêutica , Radioterapia Adjuvante , Taxa de Sobrevida , Tomografia Computadorizada por Raios X/métodos , Interface Usuário-Computador
13.
Endoscopy ; 45(3): 189-94, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23296363

RESUMO

BACKGROUND AND STUDY AIMS: Limited data are available on the endoscopic ultrasound (EUS) and fine-needle aspiration (FNA) characteristics of cystic pancreatic neuroendocrine tumors (CPanNets). The aims of this study were to describe the EUS and FNA characteristics of pathologically confirmed CPanNets and to compare these characteristics with mucinous cysts from matched patients. PATIENTS AND METHODS: From an EUS - FNA database (between 1999 and 2011), 19 patients with a pathologically confirmed CPanNet were identified. Patient characteristics, cyst fluid carcinoembryonic antigen (CEA) levels, pathology, and EUS findings were analyzed. For comparison, age- and sex-matched patients with mucinous cysts were randomly chosen from the same database. RESULTS: Of the 19 patients, two had multiple endocrine neoplasia type 1 and two had metastases. The median diameter of the lesions was 24 mm. EUS revealed unilocular lesions in 7 patients, thinly septated lesions with thin walls in 1, and mixed solid-cystic lesions in 11. EUS - FNA cytology confirmed neoplasm in 12 of the 19 patients (63.2 %). The median cyst fluid CEA level (n = 15) was 1.1 ng/mL (range 0.3 - 500 ng/mL). Compared with matched patients with mucinous cysts, the median cyst fluid CEA was lower (1.1 ng/mL vs. 400 ng/mL), thick walls were more common (66.7 % vs. 13.3 %), and diagnostic cytology was more likely (73.3 % vs. 20.0 %). CONCLUSIONS: Analysis of EUS and FNA results showed that the cyst fluid from CPanNets had a lower CEA concentration, a higher frequency of thick walls on EUS, and higher diagnostic cytology compared with mucinous cysts. These findings may aid in the diagnosis of CPanNets.


Assuntos
Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Neoplasias Císticas, Mucinosas e Serosas/diagnóstico por imagem , Tumores Neuroendócrinos/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígeno Carcinoembrionário/metabolismo , Endossonografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Císticas, Mucinosas e Serosas/metabolismo , Neoplasias Císticas, Mucinosas e Serosas/patologia , Tumores Neuroendócrinos/metabolismo , Tumores Neuroendócrinos/patologia , Cisto Pancreático/diagnóstico por imagem , Cisto Pancreático/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Estatísticas não Paramétricas
14.
Strahlenther Onkol ; 188(5): 395-401, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22318329

RESUMO

PURPOSE: The goal of the present study was to demonstrate risk factors affecting the interfractional variation in whole pelvic irradiation. PATIENTS AND METHODS: Daily image acquisitions of 101 patients with locally advanced pelvic malignancy were undertaken using a kilo-voltage orthogonal on-board imager. The baseline deviation (the shift between the initial treatment and each fraction; Value(Base)) and day-to-day variation (the shift between the previous treatment and each fraction; Value(DD)) were measured. The standard deviations (SD) along the x- (right-left), y- (cranial-caudal), and z- (anterior-posterior) axes (SD[x], SD[y], and SD[z], respectively), the 3D vector of the SD (SD[3D]), and the mean of 3D shift (mean[3D]) were calculated in each patient. Various clinical factors, lumbar pelvic balance and rotation, and the shift of 5 consecutive fractions from the initial treatment (Value(5Fx)) were investigated as risk factors. RESULTS: The prone set-up showed a larger mean(Base)[3D] than in the supine position (p =0 .063). A body mass index (BMI) ≥ 30 kg/m(2) resulted in the largest mean(DD)[3D] (p = 0.078) and SD(DD)[3D] (p = 0.058). All the SD(5Fx) along the x-, y-, and z-axes had moderate linear relationships with SD(Base) and SD(DD) (p < 0.001). The SD(5Fx)[3D] also had a moderate linear relationship with the mean(Base)[3D], mean(DD)[3D], SD(Base)[3D], and SD(DD)[3D] (p < 0.001). In multivariate analysis, the SD(5Fx) had the same significant relationship with SD(Base) and SD(DD) (p < 0.001). A BMI ≥ 30 kg/m(2) was associated with the largest SD(DD)[x] (p = 0.003). CONCLUSION: Close surveillance through high-quality and frequent image guidance is recommended for patients with extensive variations of the initial five consecutive fractions or obesity.


Assuntos
Neoplasias Pélvicas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Planejamento da Radioterapia Assistida por Computador , Risco , Tomografia Computadorizada por Raios X
15.
Minim Invasive Ther Allied Technol ; 21(5): 320-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22332891

RESUMO

BACKGROUND: The current gold standard of bladder cancer surveillance, endoscopic visualization, is manually manipulated and still has significant room for improvement in performance and controls. METHODS: This paper reports our developments toward automated bladder surveillance that employs a shape memory alloy-based machine-controlled scanning mechanism. In conjunction with the electro-mechanical advances, we use modified commercial post-processing computer vision software capable of converting cystoscopic video of the bladder into stitched panoramas. RESULTS: Experimental results conducted on a synthetic bladder demonstrate that this computer-aided scanning tool can help 82% of the entire bladder surface being scanned. Although the panoramic stitching algorithm increases the field of view and generates reasonable results in many cases, some image matching failures result in incompleteness in its full panoramic reconstruction. CONCLUSION: Our current study ensures that the automated steering mechanism can follow the desired trajectory to scan the surface of the bladder but must be improved. The current reconstruction algorithm needs further modification. Our methodology may constitute a first step in suggesting a new automated and computer-aided bladder surveillance system.


Assuntos
Cistoscopia/métodos , Lasers , Neoplasias da Bexiga Urinária/diagnóstico , Bexiga Urinária/patologia , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador , Projetos de Pesquisa , Software , Fatores de Tempo , Neoplasias da Bexiga Urinária/patologia
16.
Data Brief ; 42: 108045, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35341034

RESUMO

The data is related to minimal force thresholds perception in robotic surgical grasping applications. The experimental setup included an indenter-based haptic device acting on the fingertip of a participant and a visual system that displays grasping tasks by a surgical grasper. The experiments included the display of two presentations at different force levels (i.e., grasping and indentation) in three different modes, namely, visual-alone, haptic-alone, and bimodal (i.e., combined). For each mode, the participants were asked to identify which of the two presentations was higher. Each experiment was repeated till the termination conditions were met. Sixty participants took part in these experiments. The experiments were randomized and the threshold forces were calculated based on an algorthim. The datasets contain the individual responses of each participant, the threshold forces calculations, and the number of iterations.

17.
Laryngoscope Investig Otolaryngol ; 7(6): 1830-1836, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36544917

RESUMO

Objective: We attempted to investigate the long-term outcomes, prognostic factors, treatment failures, second primary malignancies, and salvage therapies in early (pT1-2N0) oral tongue squamous cell carcinoma (OTSCC). Methods: We retrospectively analyzed the medical records of 295 early stage OTSCC patients. Results: Two hundred ninety-five patients were enrolled. The average follow-up period was 64.5 months (range, 1-190 months). Five-year recurrence-free survival rate was 84.8% and disease-specific survival rate was 91.2%. On multivariate analysis, only the depth of invasion (DOI) exhibited significant correlations with the disease recurrence. Patient's age and DOI demonstrated a significant association with survival. A total of 53 recurrence and 35 death events occurred, with the main cause of treatment failure being regional or local recurrence. In recurrent cases, the success rate of salvage treatment was 42% at 5 years. During the follow-up period, second primary malignancy occurred in 13 patients, and 8 (61.5%) of those patients were successfully treated. Conclusions: In pT1-2N0 OTSCC, regional or local recurrence is the main recurrence pattern, whereas age and DOI >5 mm are significant prognostic factors related to recurrence and survival. Since several patients experienced second primary malignancies in the head and neck, careful and thorough surveillance may be required to detect second primary lesions. Level of Evidence: 4.

18.
Lupus ; 19(8): 989-92, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20410155

RESUMO

Primitive neuroectodermal tumor is a rare brain tumor composed of undifferentiated or poorly differentiated neuroepithelial cells with a high malignant potential that usually occurs in children, and which is only occasionally encountered in adults. A 19-year-old female with systemic lupus erythematosus presented with right hemiparesis and a headache of 10 days duration. Brain magnetic resonance imaging showed a large solid mass with necrotic portions in the left frontoparietal lobe. Primitive neuroectodermal tumor was confirmed by a neuronavigator-guided brain biopsy. This is the first case report of primitive neuroectodermal tumor associated with systemic lupus erythematosus and moyamoya disease. This case demonstrates that brain tumors, such as primitive neuroectodermal tumor, should be included in the differential diagnosis of neurological manifestations in children and adolescent patients with systemic lupus erythematosus.


Assuntos
Neoplasias Encefálicas/etiologia , Lúpus Eritematoso Sistêmico/complicações , Doença de Moyamoya/complicações , Tumores Neuroectodérmicos Primitivos/etiologia , Adulto , Neoplasias Encefálicas/patologia , Criança , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Tumores Neuroectodérmicos Primitivos/patologia , Adulto Jovem
19.
Rev Sci Instrum ; 91(1): 013321, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32012569

RESUMO

The LANSCE accelerator is currently powered by a filament-driven, biased converter-type H- ion source that operates at 10%, the highest plasma duty factor for this type of source, using only ∼2.2 SCCM of H2. The ion source needs to be replaced every 4 weeks, which takes up to 4 days. The measured negative beam current of 12-16 mA falls below the desired 24 mA acceptance of the LANCSE accelerator. The SNS (Spallation Neutron Source) RF-driven, H- ion source injects ∼50 mA of H- beam into the SNS accelerator at 60 Hz with a 6% duty factor and an availability of >99.5% but requires ∼30 SCCM of H2. Up to 7 A h of H- have been produced during the 14-weeks-long source service cycles, which is unprecedented for small emittance, high-current, pulsed H- ion sources. The emittance of the SNS source is slightly smaller than the emittance of the LANSCE source. The SNS source also features unrivaled low Cs consumption and can be installed and started up in <12 h. LANSCE and SNS are working toward the use of SNS H- ion sources on the LANSCE accelerator because they could (a) fill the LANSCE accelerator to its capacity, (b) decrease the source replacement time by a factor of up to 7, and (c) increase source lifetime by a factor of about 4. This paper discusses some of the challenges that emerge when trying to match a different H- source into an existing injector with significantly different characteristics and operating regimes.

20.
Br J Surg ; 96(4): 405-11, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19283746

RESUMO

BACKGROUND: A consensus conference has recommended close observation of branch duct intraductal papillary mucinous neoplasms (BD-IPMNs) smaller than 30 mm, without symptoms or mural nodules. This study investigated whether these recommendations could be validated in a single-centre experience of BD-IPMNs. METHODS: Some 190 patients with radiological imaging or histological findings consistent with BD-IPMN were enrolled between 1998 and 2005. Those with less than 6 months' follow-up and no histological confirmation were excluded. RESULTS: BD-IPMN was diagnosed by computed tomography and pancreatography in 105 patients and pathologically in 85. Eighteen patients had adenoma, 53 borderline malignancy, five carcinoma in situ and nine invasive carcinoma. Findings associated with malignancy were the presence of radiologically suspicious features (P < 0.001) and a cyst size of at least 30 mm (P = 0.001). Had consensus guidelines been applied, 54 patients would have undergone pancreatic resection, whereas only 28 of these patients actually had a resection; 12 of the latter patients had a malignancy compared with none of the 26 patients who were treated conservatively. CONCLUSION: A simple increase in cyst size is not a reliable predictor of malignancy. Observation is recommended for patients with a BD-IPMN smaller than 30 mm showing no suspicious features on imaging.


Assuntos
Adenocarcinoma Mucinoso/cirurgia , Carcinoma Ductal Pancreático/cirurgia , Neoplasias Pancreáticas/cirurgia , Adenocarcinoma Mucinoso/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/diagnóstico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/diagnóstico , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
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