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1.
Nature ; 618(7967): 1085-1093, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37286611

RESUMEN

G protein-coupled receptors (GPCRs) generally accommodate specific ligands in the orthosteric-binding pockets. Ligand binding triggers a receptor allosteric conformational change that leads to the activation of intracellular transducers, G proteins and ß-arrestins. Because these signals often induce adverse effects, the selective activation mechanism for each transducer must be elucidated. Thus, many orthosteric-biased agonists have been developed, and intracellular-biased agonists have recently attracted broad interest. These agonists bind within the receptor intracellular cavity and preferentially tune the specific signalling pathway over other signalling pathways, without allosteric rearrangement of the receptor from the extracellular side1-3. However, only antagonist-bound structures are currently available1,4-6, and there is no evidence to support that biased agonist binding occurs within the intracellular cavity. This limits the comprehension of intracellular-biased agonism and potential drug development. Here we report the cryogenic electron microscopy structure of a complex of Gs and the human parathyroid hormone type 1 receptor (PTH1R) bound to a PTH1R agonist, PCO371. PCO371 binds within an intracellular pocket of PTH1R and directly interacts with Gs. The PCO371-binding mode rearranges the intracellular region towards the active conformation without extracellularly induced allosteric signal propagation. PCO371 stabilizes the significantly outward-bent conformation of transmembrane helix 6, which facilitates binding to G proteins rather than ß-arrestins. Furthermore, PCO371 binds within the highly conserved intracellular pocket, activating 7 out of the 15 class B1 GPCRs. Our study identifies a new and conserved intracellular agonist-binding pocket and provides evidence of a biased signalling mechanism that targets the receptor-transducer interface.


Asunto(s)
Subunidades alfa de la Proteína de Unión al GTP Gs , Imidazolidinas , Receptores Acoplados a Proteínas G , Humanos , Regulación Alostérica , beta-Arrestinas/metabolismo , Sitios de Unión , Microscopía por Crioelectrón , Desarrollo de Medicamentos , Subunidades alfa de la Proteína de Unión al GTP Gs/química , Subunidades alfa de la Proteína de Unión al GTP Gs/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gs/ultraestructura , Imidazolidinas/química , Imidazolidinas/farmacología , Ligandos , Modelos Moleculares , Conformación Proteica/efectos de los fármacos , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/clasificación , Receptores Acoplados a Proteínas G/ultraestructura , Transducción de Señal
2.
Nature ; 599(7883): 158-164, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34552243

RESUMEN

Modulation of voltage-gated potassium (Kv) channels by auxiliary subunits is central to the physiological function of channels in the brain and heart1,2. Native Kv4 tetrameric channels form macromolecular ternary complexes with two auxiliary ß-subunits-intracellular Kv channel-interacting proteins (KChIPs) and transmembrane dipeptidyl peptidase-related proteins (DPPs)-to evoke rapidly activating and inactivating A-type currents, which prevent the backpropagation of action potentials1-5. However, the modulatory mechanisms of Kv4 channel complexes remain largely unknown. Here we report cryo-electron microscopy structures of the Kv4.2-DPP6S-KChIP1 dodecamer complex, the Kv4.2-KChIP1 and Kv4.2-DPP6S octamer complexes, and Kv4.2 alone. The structure of the Kv4.2-KChIP1 complex reveals that the intracellular N terminus of Kv4.2 interacts with its C terminus that extends from the S6 gating helix of the neighbouring Kv4.2 subunit. KChIP1 captures both the N and the C terminus of Kv4.2. In consequence, KChIP1 would prevent N-type inactivation and stabilize the S6 conformation to modulate gating of the S6 helices within the tetramer. By contrast, unlike the reported auxiliary subunits of voltage-gated channel complexes, DPP6S interacts with the S1 and S2 helices of the Kv4.2 voltage-sensing domain, which suggests that DPP6S stabilizes the conformation of the S1-S2 helices. DPP6S may therefore accelerate the voltage-dependent movement of the S4 helices. KChIP1 and DPP6S do not directly interact with each other in the Kv4.2-KChIP1-DPP6S ternary complex. Thus, our data suggest that two distinct modes of modulation contribute in an additive manner to evoke A-type currents from the native Kv4 macromolecular complex.


Asunto(s)
Microscopía por Crioelectrón , Activación del Canal Iónico , Complejos Multiproteicos/química , Complejos Multiproteicos/metabolismo , Canales de Potasio Shal/química , Canales de Potasio Shal/metabolismo , Animales , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/química , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/metabolismo , Femenino , Humanos , Proteínas de Interacción con los Canales Kv/química , Proteínas de Interacción con los Canales Kv/metabolismo , Modelos Moleculares , Complejos Multiproteicos/genética , Mutación , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/metabolismo , Oocitos/metabolismo , Canales de Potasio/química , Canales de Potasio/metabolismo , Unión Proteica , Canales de Potasio Shal/genética , Xenopus laevis
3.
J Pineal Res ; 76(3): e12952, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38587234

RESUMEN

Melatonin (5-methoxy-N-acetyltryptamine) binds with high affinity and specificity to membrane receptors. Several receptor subtypes exist in different species, of which the mammalian MT1 and MT2 receptors are the best-characterized. They are members of the G protein-coupled receptor superfamily, preferentially coupling to Gi/o proteins but also to other G proteins in a cell-context-depending manner. In this review, experts on melatonin receptors will summarize the current state of the field. We briefly report on the discovery and classification of melatonin receptors, then focus on the molecular structure of human MT1 and MT2 receptors and highlight the importance of molecular simulations to identify new ligands and to understand the structural dynamics of these receptors. We then describe the state-of-the-art of the intracellular signaling pathways activated by melatonin receptors and their complexes. Brief statements on the molecular toolbox available for melatonin receptor studies and future perspectives will round-up this review.


Asunto(s)
Melatonina , Receptor de Melatonina MT1 , Animales , Humanos , Receptores de Melatonina , Receptor de Melatonina MT1/metabolismo , Receptor de Melatonina MT2/metabolismo , Melatonina/metabolismo , Transducción de Señal , Receptores Acoplados a Proteínas G , Mamíferos/metabolismo
4.
Appl Opt ; 63(2): 305-309, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38227223

RESUMEN

This study uses a generative adversarial network to design multilevel optical anisotropic diffraction gratings with specific customizable characteristics. As input, this method uses the far electric field of polarization and intensity in each diffracted light through the gratings to design. Using the finite-difference time-domain method, the designed structures are numerically evaluated, confirming that they can be created with the intended parameters. Multilevel optical anisotropic diffraction gratings created this way can be used in various fields to develop improved optical elements.

5.
J Appl Clin Med Phys ; 25(1): e14220, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37994694

RESUMEN

PURPOSE: This study aimed to demonstrate the potential clinical applicability of an organ-contour-driven auto-matching algorithm in image-guided radiotherapy. METHODS: This study included eleven consecutive patients with cervical cancer who underwent radiotherapy in 23 or 25 fractions. Daily and reference magnetic resonance images were converted into mesh models. A weight-based algorithm was implemented to optimize the distance between the mesh model vertices and surface of the reference model during the positioning process. Within the cost function, weight parameters were employed to prioritize specific organs for positioning. In this study, three scenarios with different weight parameters were prepared. The optimal translation and rotation values for the cervix and uterus were determined based on the calculated translations alone or in combination with rotations, with a rotation limit of ±3°. Subsequently, the coverage probabilities of the following two planning target volumes (PTV), an isotropic 5 mm and anisotropic margins derived from a previous study, were evaluated. RESULTS: The percentage of translations exceeding 10 mm varied from 9% to 18% depending on the scenario. For small PTV sizes, more than 80% of all fractions had a coverage of 80% or higher. In contrast, for large PTV sizes, more than 90% of all fractions had a coverage of 95% or higher. The difference between the median coverage with translational positioning alone and that with both translational and rotational positioning was 1% or less. CONCLUSION: This algorithm facilitates quantitative positioning by utilizing a cost function that prioritizes organs for positioning. Consequently, consistent displacement values were algorithmically generated. This study also revealed that the impact of rotational corrections, limited to ±3°, on PTV coverage was minimal.


Asunto(s)
Radioterapia Guiada por Imagen , Radioterapia de Intensidad Modulada , Femenino , Humanos , Radioterapia Guiada por Imagen/métodos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/métodos , Algoritmos
6.
J Appl Clin Med Phys ; 25(9): e14403, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38952067

RESUMEN

PURPOSE: This study aimed to clarify the dosimetric impact of the respiratory motion of the liver on stereotactic body radiation therapy (SBRT) for spine metastasis and examine the utility of introducing beam avoidance (beam-off at specific gantry angles). METHODS: A total of 112 consecutive patients who underwent SBRT for spine metastasis between 2018 and 2024 were examined. Overall, 15 patients who had lesions near the liver dome were included in this study. Retrospective treatment plans were generated using computed tomography (CT) images acquired during inhalation and exhalation to evaluate the dosimetric impact of respiratory motion of the liver. The dose difference (DD) and relative value (DD%) were evaluated using the dose-volume histogram (DVH) metrics, planning target volume Dmax, D95%, spinal cord D0.035 cc, and esophagus D2.5 cc. The magnitude of the liver movements was evaluated based on differences of liver size Lave at the isocentric axial plane between the inspiratory and expiratory CT images. RESULTS: The DD in almost all DVH metrics tended to increase when the liver moved away from the target during inhalation: For example, Mean ± $ \pm $ a standard deviation (SD) DD in PTV D95% for the treatment plan incorporating beam avoidance and those without beam avoidance was 0.5 ± $\pm$ 0.3 and 0.9 ± $ \pm $ 0.6 Gy, respectively. The spinal cord D0.035 cc for those shows 0.4 ± $ \pm $ 0.2 and 0.7 ± $ \pm $ 0.7 Gy, respectively. The treatment plans without beam avoidance also showed moderate or strong correlations between Lave and DD for almost all DVH metrics. No correlation was seen in the beam avoidance plan. The spinal cord D0.035 cc revealed approximately 1 Gy or +4% in DD when Lave was < -4 cm. CONCLUSIONS: Respiratory motion of the liver dome can cause substantial dosimetric discrepancies in the dose delivered to the spinal cord, although the extent depends on patient variables. Dose assessment should be performed for determining the appropriate means of respiratory management, such as breath-hold. Alternatively, beam avoidance effectively mitigates the impact.


Asunto(s)
Hígado , Órganos en Riesgo , Radiocirugia , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada , Respiración , Neoplasias de la Columna Vertebral , Humanos , Radiocirugia/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Estudios Retrospectivos , Neoplasias de la Columna Vertebral/secundario , Neoplasias de la Columna Vertebral/radioterapia , Neoplasias de la Columna Vertebral/cirugía , Masculino , Femenino , Radioterapia de Intensidad Modulada/métodos , Hígado/diagnóstico por imagen , Hígado/efectos de la radiación , Órganos en Riesgo/efectos de la radiación , Anciano , Persona de Mediana Edad , Movimiento , Tomografía Computarizada por Rayos X/métodos , Pronóstico , Anciano de 80 o más Años
7.
Skin Res Technol ; 29(1): e13243, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36404577

RESUMEN

INTRODUCTION: Scalp angiosarcoma is a rare and aggressive cancer. Definitive radiotherapy is a treatment option for localised scalp angiosarcoma patients. Although definitive surgical resection reportedly prolongs overall survival (OS), whether initial local treatment effect affects OS when definitive radiotherapy is administered is unclear. Therefore, this study analysed whether local recurrence within 6 months of irradiation correlates with OS and cancer-specific survival (CSS). Furthermore, how local control affects patients' quality of life was investigated. MATERIALS AND METHODS: Thirty-one localised scalp angiosarcoma patients who had received definitive radiotherapy at our institution between October 2010 and July 2021 were analysed retrospectively. The most commonly used dose fractionation was 70 Gy in 35 fractions (83.9%). Local recurrence within 6 months of radiotherapy and other clinical factors were examined in univariate and subsequent multivariate analyses for correlation with OS and CSS. RESULTS: The median follow-up period was 16 months (range, 6-45 months). Local recurrence was detected in 16 patients (51.6%), 12 of whom had recurrence within 6 months. In multivariate analyses, the presence of local recurrence within 6 months of radiotherapy was significantly associated with OS and CSS (p = 0.003, 0.0001, respectively). Ten of the 16 patients with local recurrence had severe symptoms such as bleeding, pain, difficulty opening the eye and malodour. CONCLUSIONS: The initial local treatment effect was significantly associated with OS and CSS after definitive radiotherapy. Furthermore, local recurrence after radiotherapy resulted in a variety of symptoms, including bleeding and pain, which reduced the patient's quality of life.


Asunto(s)
Hemangiosarcoma , Humanos , Hemangiosarcoma/radioterapia , Hemangiosarcoma/patología , Cuero Cabelludo/patología , Estudios Retrospectivos , Relevancia Clínica , Calidad de Vida , Dolor
8.
J Appl Clin Med Phys ; 24(10): e14073, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37317937

RESUMEN

PURPOSE: This study was conducted to determine the margins and timing of replanning by assessing the daily interfractional cervical and uterine motions using magnetic resonance (MR) images. METHODS: Eleven patients with cervical cancer, who underwent intensity-modulated radiotherapy (IMRT) in 23-25 fractions, were considered in this study. The daily and reference MR images were converted into three-dimensional (3D) shape models. Patient-specific anisotropic margins were calculated from the proximal 95% of vertices located outside the surface of the reference model. Population-based margins were defined as the 90th percentile values of the patient-specific margins. The expanded volume of interest (expVOI) for the cervix and uterus was generated by expanding the reference model based on the population-based margin to calculate the coverage for daily deformable mesh models. For comparison, expVOIconv was generated using conventional margins: right (R), left (L), anterior (A), posterior (P), superior (S), and inferior (I) were (5, 5, 15, 15, 10, 10) and (10, 10, 20, 20, 15, 15) mm for the cervix and uterus, respectively. Subsequently, a replanning scenario was developed based on the cervical volume change. ExpVOIini and expVOIreplan were generated before and after replanning, respectively. RESULTS: Population-based margins were (R, L, A, P, S, I) of (7, 7, 11, 6, 11, 8) and (14, 13, 27, 19, 15, 21) mm for the cervix and uterus, respectively. The timing of replanning was found to be the 16th fraction, and the volume of expVOIreplan decreased by >30% compared to that of expVOIini . However, margins cannot be reduced to ensure equivalent coverage after replanning. CONCLUSION: We determined the margins and timing of replanning through detailed daily analysis. The margins of the cervix were smaller than conventional margins in some directions, while the margins of the uterus were larger in almost all directions. A margin equivalent to that at the initial planning was required for replanning.


Asunto(s)
Radioterapia de Intensidad Modulada , Neoplasias del Cuello Uterino , Femenino , Humanos , Cuello del Útero/diagnóstico por imagen , Cuello del Útero/patología , Útero/diagnóstico por imagen , Útero/patología , Movimiento (Física) , Imagen por Resonancia Magnética/métodos , Neoplasias del Cuello Uterino/diagnóstico por imagen , Neoplasias del Cuello Uterino/radioterapia , Neoplasias del Cuello Uterino/patología , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/métodos , Dosificación Radioterapéutica
9.
J Appl Clin Med Phys ; 24(4): e13865, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36573258

RESUMEN

BACKGROUND: The setup of lung shield (LS) in total body irradiation (TBI) with the computed radiography (CR) system is a time-consuming task and has not been quantitatively evaluated. The TBI mobile imager (TBI-MI) can solve this problem through real-time monitoring. Therefore, this study aimed to perform commissioning and performance evaluation of TBI-MI to promote its use in clinical practice. METHODS: The source-axis distance in TBI treatment, TBI-MI (CNERGY TBI, Cablon Medical B.V.), and the LS position were set to 400, 450, and 358 cm, respectively. The evaluation items were as follows: accuracy of image scaling and measured displacement error of LS, image quality (linearity, signal-to-noise ratio, and modulation transfer function) using an EPID QC phantom, optimal thresholding to detect intra-fractional motion in the alert function, and the scatter radiation dose from TBI-MI. RESULTS: The accuracy of image scaling and the difference in measured displacement of the LS was <4 mm in any displacements and directions. The image quality of TBI imager was slightly inferior to the CR image but was visually acceptable in clinical practice. The signal-to-noise ratio was improved at high dose rate. The optimal thresholding value to detect a 10-mm body displacement was determined to be approximately 5.0%. The maximum fraction of scattering radiation to irradiated dose was 1.7% at patient surface. CONCLUSION: MI-TBI can quantitatively evaluate LS displacement with acceptable image quality. Furthermore, real-time monitoring with alert function to detect intrafraction patient displacement can contribute to safe TBI treatment.


Asunto(s)
Planificación de la Radioterapia Asistida por Computador , Irradiación Corporal Total , Humanos , Fantasmas de Imagen , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos
10.
J Appl Clin Med Phys ; 24(5): e13915, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36934441

RESUMEN

PURPOSE: We measure the dose distribution of gated delivery for different target motions and estimate the gating latency in a magnetic resonance-guided radiotherapy (MRgRT) system. METHOD: The dose distribution accuracy of the gated MRgRT system (MRIdian, Viewray) was investigated using an in-house-developed phantom that was compatible with the magnetic field and gating method. This phantom contains a simulated tumor and a radiochromic film (EBT3, Ashland, Inc.). To investigate the effect of the number of beam switching and target velocity on the dose distribution, two types of target motions were applied. One is that the target was periodically moved at a constant velocity of 5 mm/s with different pause times (0, 1, 3, 10, and 20 s) between the motions. During different pause times, different numbers of beams were switched on/off. The other one is that the target was moved at velocities of 3, 5, 8, and 10 mm/s without any pause (i.e., continuous motion). The gated method was applied to these motions at MRIdian, and the dose distributions in each condition were measured using films. To investigate the relation between target motion and dose distribution in the gating method, we compared the results of the gamma analysis of the calculated and measured dose distributions. Moreover, we analytically estimated the gating latencies from the dose distributions measured using films and the gamma analysis results. RESULTS: The gamma pass rate linearly decreased with increasing beam switching and target velocity. The overall gating latencies of beam-hold and beam-on were 0.51 ± 0.17 and 0.35 ± 0.05 s, respectively. CONCLUSIONS: Film measurements highlighted the factors affecting the treatment accuracy of the gated MRgRT system. Our analytical approach, employing gamma analysis on films, can be used to estimate the overall latency of the gated MRgRT system.


Asunto(s)
Planificación de la Radioterapia Asistida por Computador , Humanos , Movimiento (Física) , Espectroscopía de Resonancia Magnética , Dosificación Radioterapéutica , Fantasmas de Imagen
11.
J Appl Clin Med Phys ; 24(6): e14040, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37191875

RESUMEN

PURPOSE: The Medical Physics Working Group of the Radiation Therapy Study Group at the Japan Clinical Oncology Group is currently developing a virtual audit system for intensity-modulated radiation therapy dosimetry credentialing. The target dosimeters include films and array detectors, such as ArcCHECK (Sun Nuclear Corporation, Melbourne, Florida, USA) and Delta4 (ScandiDos, Uppsala, Sweden). This pilot study investigated the feasibility of our virtual audit system using previously acquired data. METHODS: We analyzed 46 films (32 and 14 in the axial and coronal planes, respectively) from 29 institutions. Global gamma analysis between measured and planned dose distributions used the following settings: 3%/3 mm criteria (the dose denominator was 2 Gy), 30% threshold dose, no scaling of the datasets, and 90% tolerance level. In addition, 21 datasets from nine institutions were obtained for array evaluation. Five institutions used ArcCHECK, while the others used Delta4. Global gamma analysis was performed with 3%/2 mm criteria (the dose denominator was the maximum calculated dose), 10% threshold dose, and 95% tolerance level. The film calibration and gamma analysis were conducted with in-house software developed using Python (version 3.9.2). RESULTS: The means ± standard deviations of the gamma passing rates were 99.4 ± 1.5% (range, 92.8%-100%) and 99.2 ± 1.0% (range, 97.0%-100%) in the film and array evaluations, respectively. CONCLUSION: This pilot study demonstrated the feasibility of virtual audits. The proposed virtual audit system will contribute to more efficient, cheaper, and more rapid trial credentialing than on-site and postal audits; however, the limitations should be considered when operating our virtual audit system.


Asunto(s)
Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada , Humanos , Proyectos Piloto , Japón , Habilitación Profesional , Radiometría , Dosificación Radioterapéutica , Oncología Médica , Fantasmas de Imagen
12.
J Appl Clin Med Phys ; 23(5): e13579, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35263027

RESUMEN

PURPOSE: Adaptive radiotherapy requires auto-segmentation in patients with head and neck (HN) cancer. In the current study, we propose an auto-segmentation model using a generative adversarial network (GAN) on magnetic resonance (MR) images of HN cancer for MR-guided radiotherapy (MRgRT). MATERIAL AND METHODS: In the current study, we used a dataset from the American Association of Physicists in Medicine MRI Auto-Contouring (RT-MAC) Grand Challenge 2019. Specifically, eight structures in the MR images of HN region, namely submandibular glands, lymph node level II and level III, and parotid glands, were segmented with the deep learning models using a GAN and a fully convolutional network with a U-net. These images were compared with the clinically used atlas-based segmentation. RESULTS: The mean Dice similarity coefficient (DSC) of the U-net and GAN models was significantly higher than that of the atlas-based method for all the structures (p < 0.05). Specifically, the maximum Hausdorff distance (HD) was significantly lower than that in the atlas method (p < 0.05). Comparing the 2.5D and 3D U-nets, the 3D U-net was superior in segmenting the organs at risk (OAR) for HN patients. The DSC was highest for 0.75-0.85, and the HD was lowest within 5.4 mm of the 2.5D GAN model in all the OARs. CONCLUSIONS: In the current study, we investigated the auto-segmentation of the OAR for HN patients using U-net and GAN models on MR images. Our proposed model is potentially valuable for improving the efficiency of HN RT treatment planning.


Asunto(s)
Aprendizaje Profundo , Neoplasias de Cabeza y Cuello , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética , Órganos en Riesgo
13.
Rheumatology (Oxford) ; 60(3): 1553-1562, 2021 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-33175976

RESUMEN

OBJECTIVE: SSc is a connective tissue disease with multisystem disorder induced by the inflammation and fibrosis following T and B cell abnormalities. Follicular helper CD4+ T (TFH) cells play a crucial role in the formation of germinal centres and specialize in interacting to aid B cell differentiation. We aimed to investigate TFH cells and their subsets to evaluate their involvement with B cell alteration in SSc. METHOD: Circulating TFH cells (cTFH), B cells and their subsets were assessed by flow cytometry. The concentration of serum cytokines was measured by cytokine array assay. Immunohistochemistry and IF were performed to evaluate the migration of TFH cells in SSc skin lesions. RESULTS: The proportion of cTFH cells did not differ from controls, but their subsets were imbalanced in SSc patients. The frequency of TFH 1 was increased and correlated with ACA titre, serum IgM or CRP levels of patients, and cytokine concentrations of IL-21 and IL-6 that induce B cell differentiation in SSc. cTFH cells from SSc showed activated phenotype with expressing higher cytokine levels compared with controls. The frequency of TFH 17 was also increased, but was not correlated with a high level of Th17 cytokines in patients' sera. Furthermore, infiltration of TFH cells was found in skin lesion of SSc patients. CONCLUSION: We here describe an imbalance of cTFH toward TFH 1 that may induce B cell alteration through IL-21 and IL-6 pathways and promote inflammation, contributing to the pathogenesis of SSc disease.


Asunto(s)
Linfocitos B/patología , Esclerodermia Sistémica/patología , Células T Auxiliares Foliculares/patología , Adulto , Anciano , Anciano de 80 o más Años , Linfocitos B/metabolismo , Biomarcadores/sangre , Estudios de Casos y Controles , Diferenciación Celular , Citocinas/sangre , Femenino , Citometría de Flujo , Humanos , Masculino , Persona de Mediana Edad , Esclerodermia Sistémica/inmunología , Células T Auxiliares Foliculares/metabolismo
14.
BMC Infect Dis ; 21(1): 37, 2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-33413196

RESUMEN

BACKGROUND: Previous studies have reported poor prognosis in cases of tetanus that develops after bacteria enters via breast cancer-related skin ulcers that are not treated with surgical debridement. Herein, we review the literature concerning this presentation and report the first case of complete remission from tetanus without surgical debridement of the skin ulcer. CASE PRESENTATION: An Asian woman aged over 60 years had a history of skin ulcer caused by breast cancer. She was diagnosed with tetanus due to trismus and opisthotonus. Based on the suspicion that the skin ulcer was the portal of entry for tetanus bacteria, we considered several debridement and thoracic surgical options for tetanus treatment. However, debridement was not performed as the surgery was considered high risk and the patient did not consent to it. The patient received treatment with anti-tetanus globulin and metronidazole; sound insulation and shielding were also performed in a dark room. Subsequently, the patient's symptoms improved, and sound insulation and deep sedation management were completed on 19th day of hospitalization. With no symptom recurrence, the patient was discharged on Day 54. To date, over 3 years after treatment, no evidence of tetanus recurrence has been observed. The case was characterized by a lack of autonomic hyperactivity. The tetanus severity was likely representative of the low amount of toxin that the patient was exposed to. CONCLUSION: This case involved moderate severity tetanus originating from a chronic skin ulcer related to breast cancer. The patient survived without undergoing extensive debridement. No evidence of tetanus relapse was observed during the follow-up period, likely due to vaccination that might have restored the patient's active immunity. Debridement is not always necessary for tetanus complicated by breast cancer skin ulcers. Furthermore, appropriate toxoid vaccination is critical for preventing the onset and recurrence of tetanus in these patients.


Asunto(s)
Neoplasias de la Mama/complicaciones , Úlcera Cutánea/microbiología , Tétanos/etiología , Tétanos/terapia , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Femenino , Humanos , Metástasis Linfática/patología , Metronidazol , Persona de Mediana Edad , Recurrencia Local de Neoplasia/complicaciones , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/secundario , Úlcera Cutánea/complicaciones , Tétanos/cirugía , Toxoide Tetánico/uso terapéutico
15.
J Appl Clin Med Phys ; 22(7): 255-265, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34159719

RESUMEN

PURPOSE: This study aimed to develop a physical geometric phantom for the deformable image registration (DIR) credentialing of radiotherapy centers for a clinical trial and tested the feasibility of the proposed phantom at multiple domestic and international institutions. METHODS AND MATERIALS: The phantom reproduced tumor shrinkage, rectum shape change, and body shrinkage using several physical phantoms with custom inserts. We tested the feasibility of the proposed phantom using 5 DIR patterns at 17 domestic and 2 international institutions (21 datasets). Eight institutions used the MIM software (MIM Software Inc, Cleveland, OH); seven used Velocity (Varian Medical Systems, Palo Alto, CA), and six used RayStation (RaySearch Laboratories, Stockholm, Sweden). The DIR accuracy was evaluated using the Dice similarity coefficient (DSC) and Hausdorff distance (HD). RESULTS: The mean and one standard deviation (SD) values (range) of DSC were 0.909 ± 0.088 (0.434-0.984) and 0.909 ± 0.048 (0.726-0.972) for tumor and rectum proxies, respectively. The mean and one SD values (range) of the HD value were 5.02 ± 3.32 (1.53-20.35) and 5.79 ± 3.47 (1.22-21.48) (mm) for the tumor and rectum proxies, respectively. In three patterns evaluating the DIR accuracy within the entire phantom, 61.9% of the data had more than a DSC of 0.8 in both tumor and rectum proxies. In two patterns evaluating the DIR accuracy by focusing on tumor and rectum proxies, all data had more than a DSC of 0.8 in both tumor and rectum proxies. CONCLUSIONS: The wide range of DIR performance highlights the importance of optimizing the DIR process. Thus, the proposed method has considerable potential as an evaluation tool for DIR credentialing and quality assurance.


Asunto(s)
Algoritmos , Procesamiento de Imagen Asistido por Computador , Habilitación Profesional , Humanos , Planificación de la Radioterapia Asistida por Computador , Suecia , Tomografía Computarizada por Rayos X
16.
BMC Urol ; 20(1): 196, 2020 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-33317509

RESUMEN

BACKGROUND: In definitive radiation therapy for prostate cancer, the SpaceOAR® System, a hydrogel spacer, is widely used to decrease the irradiated dose and toxicity of rectum. On the other hand, periprostatic abscesses formation and rectal perforation are known as rare adverse effects of SpaceOAR. Nevertheless, there is a lack of reports clarifying the association between aggravation of abscesses and radiation therapy, and hyperbaric oxygen therapy (HBOT) is effective for a peri-SpaceOAR abscess and rectal perforation. CASE PRESENTATION: We report a case of a 78-year-old high-risk prostate cancer patient. After SpaceOAR insertion into the correct space, he started to receive external beam radiation therapy (EBRT). He developed a fever, perineal pain and frequent urination after the completion of EBRT, and the magnetic resonance imaging (MRI) revealed a peri-SpaceOAR abscess. Scheduled brachytherapy was postponed, administration of antibiotics and opioid via intravenous drip was commenced, and transperineal drainage was performed. After the alleviation of the abscess, additional EBRT instead of brachytherapy was performed with MRI-guided radiation therapy (MRgRT). On the last day of the MRgRT, perineal pain reoccurred, and MRI and colonoscopy detected the rectal perforation. He received an intravenous antibiotics drip and HBOT, and fully recovered from the rectal perforation. CONCLUSIONS: Our report indicates that EBRT can lead to a severe rectum complication by causing inflammation for patients with a peri-SpaceOAR abscess. Furthermore, HBOT was effective for the peri-SpaceOAR abscess and rectal perforation associated with EBRT.


Asunto(s)
Braquiterapia/efectos adversos , Oxigenoterapia Hiperbárica , Neoplasias de la Próstata/radioterapia , Fístula Rectal/etiología , Fístula Rectal/terapia , Absceso Abdominal/etiología , Absceso Abdominal/terapia , Anciano , Braquiterapia/instrumentación , Humanos , Hidrogeles , Perforación Intestinal/etiología , Perforación Intestinal/terapia , Masculino , Dosificación Radioterapéutica , Enfermedades del Recto/etiología , Enfermedades del Recto/terapia
17.
Eur Neurol ; 83(1): 49-55, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32209795

RESUMEN

INTRODUCTION: Since independent gait is an important factor for home discharge, early prediction of independent gait after stroke is essential. The revised version of the Ability for Basic Movement Scale II (ABMS II) has been developed and validated for assessment of basic movements poststroke. OBJECTIVE: The purpose of this study was to investigate the predictive value of the ABMS II score for independent gait in acute stroke patients with hemiplegia. METHODS: We included 67 patients with first stroke and a unilateral lesion who were admitted to the stroke care unit. We evaluated the gait on the 14th and 90th days from admission. RESULTS: The ABMS II score was significantly higher in patients with independent gait on both the 14th and 90th days from admission. On receiver operating characteristic curve analysis, a minimum score of 26 points was predictive of independent gait on the 14th day from admission. Similarly, a score of 15 points was predictive of independent gait on the 90th day from admission. CONCLUSIONS: The ABMS II score is a useful predictor of independent gait in acute stroke patients with hemiplegia.


Asunto(s)
Marcha , Hemiplejía/etiología , Índice de Severidad de la Enfermedad , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular/complicaciones , Actividades Cotidianas , Anciano , Femenino , Hemiplejía/rehabilitación , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Curva ROC , Estudios Retrospectivos
18.
Jpn J Clin Oncol ; 49(9): 881-885, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31613355

RESUMEN

A single-arm multi-center confirmatory trial was started in Japan to confirm the efficacy and safety of post-radical hysterectomy concurrent chemoradiotherapy using intensity-modulated radiation therapy (IMRT-CCRT) for patients with high-risk uterine cervical cancer, for which the current standard treatment is CCRT using three-dimensional conformal radiation therapy (3DCRT-CCRT). This study began in April 2017 and a total of 220 patients will be accrued from 44 institutions within 3.5 years. The primary endpoint is 3-year relapse-free survival. The secondary endpoints are overall survival, loco-regional relapse-free survival, proportion of late lower gastrointestinal adverse events greater than or equal to grade 3, proportion of lower edema limbs, adverse events, and serious adverse events. This trial was registered at the Japan Registry of Clinical Trials as jRCTs031180194 (https://jrct.niph.go.jp/).


Asunto(s)
Quimioradioterapia/efectos adversos , Radioterapia de Intensidad Modulada/efectos adversos , Neoplasias del Cuello Uterino/terapia , Adulto , Anciano , Femenino , Humanos , Histerectomía , Japón , Persona de Mediana Edad , Periodo Posoperatorio , Radioterapia Conformacional/efectos adversos , Neoplasias del Cuello Uterino/cirugía , Adulto Joven
19.
Int J Clin Oncol ; 24(5): 575-582, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30580379

RESUMEN

BACKGROUND: The aim of this study was to evaluate the effects of treatment with both three-dimensional radiotherapy (3DRT) and weekly 40-mg/m2 cisplatin on postoperative uterine cervical cancer patients with high-risk prognostic factors. METHODS: We conducted a retrospective multi-institutional chart review of postoperative uterine cervical cancer patients with high-risk prognostic factors who had been treated with both 3DRT and weekly 40-mg/m2 cisplatin from 2007 to 2012. Each participating hospital provided detailed information regarding patient characteristics, treatment outcomes, and treatment complications. RESULTS: The eligible 96 patients were analyzed. The median follow-up period was 61 months. The 3-year relapse-free survival, overall survival (OS), and locoregional relapse-free survival (LRFS) rates were 76%, 90%, and 88%, respectively. In multivariate analysis, the histological finding of either adenocarcinoma or adenosquamous carcinoma was a significant risk factor for both OS and LRFS. The percentage of patients with grade ≥ 3 acute hematologic toxicity, acute lower gastrointestinal toxicity (GIT), and late lower GIT were 45%, 19%, and 17%, respectively. CONCLUSIONS: The outcomes of concurrent chemoradiotherapy (CCRT) using weekly 40-mg/m2 cisplatin are similar to those in the previous studies that used several chemotherapy regimens. However, postoperative CCRT using 3DRT had a high level of late GIT.


Asunto(s)
Quimioradioterapia/efectos adversos , Cisplatino/uso terapéutico , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/radioterapia , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/mortalidad , Adenocarcinoma/radioterapia , Adenocarcinoma/cirugía , Adulto , Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Carcinoma Adenoescamoso/tratamiento farmacológico , Carcinoma Adenoescamoso/mortalidad , Carcinoma Adenoescamoso/radioterapia , Carcinoma Adenoescamoso/cirugía , Quimioradioterapia/métodos , Cisplatino/administración & dosificación , Esquema de Medicación , Femenino , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/tratamiento farmacológico , Periodo Posoperatorio , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento , Neoplasias del Cuello Uterino/mortalidad , Neoplasias del Cuello Uterino/cirugía
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