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1.
J Chem Phys ; 160(14)2024 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-38591671

RESUMEN

A frequency-dependent dielectric constant characterizes the dielectric response of a medium and also represents the time scale of system's collective dynamics. Although it is valuable not only academically but also practically for developing advanced devices, getting the value of a solution at the interface with a solid or electrode surface is challenging both experimentally and computationally. Here, we propose a computational method that imitates the dielectric spectroscopy and AC impedance measurement. It combines a time-dependent voltage applied molecular dynamics simulation with an equivalent circuit representation of a system composed of a solution confined between two identical electrodes. It gives the frequency-dependent dielectric constants of the bulk solution and the interface simultaneously. Unlike the conventional method, it does not require computation of a dipole autocorrelation function and its Fourier transformation. Application of the method on a system of water confined between polarizable Pt electrodes gives the static dielectric constant and the relaxation time of the bulk water in good agreement with previous simulation results and experimental values. In addition, it gives a much smaller static dielectric constant at the interface, consistent with previous observations. The outline of the dielectric dispersion curve of the interface seems similar to that of the bulk, but the relaxation time is several times faster.

2.
IEEE Trans Biomed Eng ; 71(2): 377-387, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37450357

RESUMEN

OBJECTIVE: The usage of Riemannian geometry for Brain-computer interfaces (BCIs) has gained momentum in recent years. Most of the machine learning techniques proposed for Riemannian BCIs consider the data distribution on a manifold to be unimodal. However, the distribution is likely to be multimodal rather than unimodal since high-data variability is a crucial limitation of electroencephalography (EEG). In this paper, we propose a novel data modeling method for considering complex data distributions on a Riemannian manifold of EEG covariance matrices, aiming to improve BCI reliability. METHODS: Our method, Riemannian spectral clustering (RiSC), represents EEG covariance matrix distribution on a manifold using a graph with proposed similarity measurement based on geodesic distances, then clusters the graph nodes through spectral clustering. This allows flexibility to model both a unimodal and a multimodal distribution on a manifold. RiSC can be used as a basis to design an outlier detector named outlier detection Riemannian spectral clustering (odenRiSC) and a multimodal classifier named multimodal classifier Riemannian spectral clustering (mcRiSC). All required parameters of odenRiSC/mcRiSC are selected in data-driven manner. Moreover, there is no need to pre-set a threshold for outlier detection and the number of modes for multimodal classification. RESULTS: The experimental evaluation revealed odenRiSC can detect EEG outliers more accurately than existing methods and mcRiSC outperformed the standard unimodal classifier, especially on high-variability datasets. CONCLUSION: odenRiSC/mcRiSC are anticipated to contribute to making real-life BCIs outside labs and neuroergonomics applications more robust. SIGNIFICANCE: RiSC can work as a robust EEG outlier detector and multimodal classifier.


Asunto(s)
Algoritmos , Interfaces Cerebro-Computador , Reproducibilidad de los Resultados , Aprendizaje Automático , Electroencefalografía/métodos
3.
Radiat Oncol ; 18(1): 180, 2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37919745

RESUMEN

BACKGROUND: Intensity-modulated radiation therapy (IMRT) requires delivery quality assurance (DQA) to ensure treatment accuracy and safety. Irradiation techniques such as helical tomotherapy (HT) have become increasingly complex, rendering conventional verification methods insufficient. This study aims to develop a novel DQA system to simultaneously verify dose distribution and multi-leaf collimator (MLC) opening during HT. METHODS: We developed a prototype detector consisting of a cylindrical plastic scintillator (PS) and a cooled charge-coupled device (CCD) camera. Scintillation light was recorded using a CCD camera. A TomoHDA (Accuray Inc.) was used as the irradiation device. The characteristics of the developed system were evaluated based on the light intensity. The IMRT plan was irradiated onto the PS to record a moving image of the scintillation light. MLC opening and light distribution were obtained from the recorded images. To detect MLC opening, we placed a region of interest (ROI) on the image, corresponding to the leaf position, and analyzed the temporal change in the light intensity within each ROI. Corrections were made for light changes due to differences in the PS shape and irradiation position. The corrected light intensity was converted into the leaf opening time (LOT), and an MLC sinogram was constructed. The reconstructed MLC sinogram was compared with that calculated using the treatment planning system (TPS). Light distribution was obtained by integrating all frames obtained during IMRT irradiation. The light distribution was compared with the dose distribution calculated using the TPS. RESULTS: The LOT and the light intensity followed a linear relationship. Owing to MLC movements, the sensitivity and specificity of the reconstructed sinogram exceeded 97%, with an LOT error of - 3.9 ± 7.8%. The light distribution pattern closely resembled that of the dose distribution. The average dose difference and the pass rate of gamma analysis with 3%/3 mm were 1.4 ± 0.2% and 99%, respectively. CONCLUSION: We developed a DQA system for simultaneous and accurate verification of both dose distribution and MLC opening during HT.


Asunto(s)
Radioterapia de Intensidad Modulada , Humanos , Radioterapia de Intensidad Modulada/métodos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Fantasmas de Imagen
4.
Curr Oncol ; 30(5): 5062-5071, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37232841

RESUMEN

The indications for stereotactic body radiotherapy (SBRT) for prostate cancer have increased. However, the relationships between adverse events and risk factors remain unclear. This study aimed to clarify associations between adverse events and dose index for prostate SBRT. Participants comprised 145 patients irradiated with 32-36 Gy in 4 fractions. Radiotherapy-related risk factors such as dose-volume histogram parameters and patient-related risk factors such as T stage and Gleason score were evaluated in a competing risk analysis. Median follow-up duration was 42.9 months. A total of 9.7% had acute Grade ≥ 2 GU toxicities and 4.8% had acute Grade ≥ 2 GI toxicities. A total of 11.1% had late Grade ≥ 2 GU toxicities and 7.6% had late Grade ≥ 2 GI toxicities. Two (1.4%) patients suffered from late Grade 3 GU toxicities. Similarly, two (1.4%) patients suffered from late Grade 3 GI toxicities. Acute GU and GI events correlated with prostate volume and dose to the hottest 10 cc volume (D10cc)/volumes receiving a minimum of 30 Gy (V30 Gy) of rectum, respectively. Late GI toxicity, frequency, and rectal hemorrhage correlated with rectal D0.1 cc/D1 cc, maximum dose to the bladder, and rectal D0.1 cc, respectively. Toxicities after prostate SBRT using 32-36 Gy/4 fractions were acceptable. Our analysis showed that acute toxicities correlated with volume receiving a medium dose level, and late toxicities correlated with highest point dose of organs at risk.


Asunto(s)
Neoplasias de la Próstata , Radiocirugia , Masculino , Humanos , Próstata , Radiocirugia/efectos adversos , Pelvis , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/tratamiento farmacológico , Recto
5.
Heliyon ; 8(12): e12117, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36544846

RESUMEN

We aimed to clarify expert skills in refinery patrol inspection using data collected through a virtual reality experimental system. As body positioning and postural changes are relevant factors during refinery patrol inspection tasks, we measured and analyzed both visual attention and head positioning behavior among experts and "knowledgeable novices" who were engaged in the engineering of the refinery but had less inspection experience. The participants performed a simulated inspection task, and the results showed that 1) expert inspectors could find more defects compared to knowledgeable novices, 2) visual attention behavior was similar between knowledgeable novices and experts, and 3) experts tended to position their heads at various heights and further from the inspection target to obtain visual information more effectively from the target compared to knowledgeable novices. This study presented the differences in head positioning behavior between expert and novice inspectors for the first time. These results suggest that to evaluate the skills used in inspecting relatively larger targets, both visual attention and head positioning behavior of the inspectors must be measured.

6.
BMC Anesthesiol ; 22(1): 214, 2022 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-35820847

RESUMEN

BACKGROUND: Klippel-Trenaunay-Weber syndrome (KTWS) is a rare congenital malformation. Although there have been few reports on anaesthetic management of patients with KTWS, there is a lack of data on anaesthetic management for abdominal aortic aneurysm (AAA) surgeries in these patients. CASE PRESENTATION: A 74-year-old man (height, 160 cm and body weight, 51.5 kg) with KTWS was scheduled for AAA replacement. Abdominal computed tomography (CT) showed prominent tortuosity below the abdominal aorta with an infrarenal abdominal aortic aneurysm, right common iliac artery aneurysm, and right external iliac artery aneurysm. Moreover, a remarkably noted arteriovenous fistula had developed between the aneurysm and peripheral artery. General anaesthesia was induced. Furthermore, a central venous catheter and an 8.5 French sheath in the left internal jugular vein were inserted. During the operation, bleeding from a collateral vessel in the cross-clamped aorta led the surgeon to decide to perform aneurysmorrhaphy. Intraoperatively, blood loss was 1500 ml, and 20 units of red blood cell concentrate were used. CONCLUSIONS: Regarding AAA procedures in patients with KTWS, aortic cross-clamping may not sufficiently intercept blood flow due to collateral vessels. In these patients, the anaesthesiologist must be prepared to transfuse blood more rapidly and frequently than during normal AAA procedures.


Asunto(s)
Anestésicos , Aneurisma de la Aorta Abdominal , Síndrome de Klippel-Trenaunay-Weber , Anciano , Aorta Abdominal/diagnóstico por imagen , Aorta Abdominal/cirugía , Aneurisma de la Aorta Abdominal/complicaciones , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/cirugía , Arterias , Hemorragia , Humanos , Síndrome de Klippel-Trenaunay-Weber/complicaciones , Síndrome de Klippel-Trenaunay-Weber/cirugía , Masculino
7.
Gan To Kagaku Ryoho ; 49(4): 437-439, 2022 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-35444129

RESUMEN

A 65-year-old woman was admitted to our institution with sonography results indicating a caudate lobe mass. CT showed a large low-density mass in the caudate lobe, extensively involving the inferior vena cava and main portal vein. Moderately differentiated adenocarcinoma was found on transcutaneous biopsy. We therefore regarded this tumor as a severe locally advanced hilar cholangiocarcinoma and initiated gemcitabine/cisplatin combined chemotherapy. The tumor gradually reduced in size. However, after 28 courses of treatment, CT showed persistent tumor invasion in the left trunk of the portal vein and inferior vena cava invasion in succession in the middle; the tumor had not yet invaded the left hepatic vein. Owing to myelosuppression and general malaise, it was difficult to continue chemotherapy. After 32 courses of treatment, the patient underwent a left trisegmentectomy with combined resection of the portal vein and inferior vena cava. Postoperative microscopic findings revealed no apparent invasion of the tumor in the inferior vena cava, thus suggesting successful R0 resection. The patient is alive without recurrence 18 months postoperatively.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Tumor de Klatskin , Anciano , Neoplasias de los Conductos Biliares/tratamiento farmacológico , Neoplasias de los Conductos Biliares/patología , Neoplasias de los Conductos Biliares/cirugía , Colangiocarcinoma/tratamiento farmacológico , Colangiocarcinoma/patología , Colangiocarcinoma/cirugía , Cisplatino , Desoxicitidina/análogos & derivados , Quimioterapia Combinada , Femenino , Hepatectomía/métodos , Humanos , Tumor de Klatskin/cirugía , Vena Porta/patología , Vena Porta/cirugía , Vena Cava Inferior/patología , Vena Cava Inferior/cirugía , Gemcitabina
8.
Nutrients ; 14(3)2022 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-35276796

RESUMEN

Since many nutrients, including the three major ones of glucose, dipeptides, and cholesterol, are mainly absorbed in the small intestine, the assessment of their effects on intestinal tissue is important for the study of food absorption. However, cultured intestinal cell lines, such as Caco-2 cells, or animal models, which differ from normal human physiological conditions, are generally used for the evaluation of intestinal absorption and digestion. Therefore, it is necessary to develop an alternative in vitro method for more accurate analyses. In this study, we demonstrate inhibitory effects on nutrient absorption through nutrient transporters using three-dimensional xenogeneic-free human intestinal organoids (XF-HIOs), with characteristics of the human intestine, as we previously reported. We first show that the organoids absorbed glucose, dipeptide, and cholesterol in a transporter-dependent manner. Next, we examine the inhibitory effect of natural ingredients on the absorption of glucose and cholesterol. We reveal that glucose absorption was suppressed by epicatechin gallate or nobiletin, normally found in green tea catechin or citrus fruits, respectively. In comparison, cholesterol absorption was not inhibited by luteolin and quercetin, contained in some vegetables. Our findings highlight the usefulness of screening for the absorption of functional food substances using XF-HIOs.


Asunto(s)
Absorción Intestinal , Organoides , Animales , Células CACO-2 , Humanos , Intestinos/fisiología , Nutrientes
9.
Clin J Gastroenterol ; 14(6): 1779-1784, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34558055

RESUMEN

A 77-year-old female patient consulted our hospital for an abnormal shadow observed on chest X-ray. Computed tomography revealed the shadow of a mass in the right lower lung lobe and two shadows of masses in the pancreatic head and body. 18F-fluorodeoxyglucose-positron emission tomography showed an intense uptake only in the fields corresponding to these three masses. Each mass was diagnosed as leiomyosarcoma by transcutaneous needle biopsy of the pulmonary mass and endoscopic ultrasound-guided fine-needle aspiration of the pancreatic masses. The primary site was the lung because the pulmonary lesion was solitary, and no tumor was found in other organs. In English language literature, a case of primary pulmonary leiomyosarcoma with metastasis solely to the pancreas has not yet been reported to the best of our knowledge.


Asunto(s)
Leiomiosarcoma , Neoplasias Pancreáticas , Anciano , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico , Femenino , Humanos , Leiomiosarcoma/diagnóstico por imagen , Pulmón , Páncreas/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico por imagen
10.
Tohoku J Exp Med ; 254(1): 49-55, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-34053967

RESUMEN

Whether trastuzumab use beyond disease progression is beneficial in second-line treatment for patients with unresectable human epidermal growth factor receptor 2 (HER2)-positive gastric cancer remains to be elucidated. We conducted this phase II study to assess whether trastuzumab plus docetaxel was effective for patients with previously treated advanced HER2-positive gastric cancer. This trial was a single-arm, open-label, multicenter, phase II study, conducted by Tohoku Clinical Oncology Research and Education Society (T-CORE). Patients aged 20 years or older who had advanced HER2-positive gastric cancer and were refractory to trastuzumab, fluoropyrimidine, and cisplatin were enrolled. Patients were treated with 6 mg/kg trastuzumab and 60 mg/m2 docetaxel every 3 weeks. The primary endpoint was the overall response rate. The threshold overall response rate was estimated to be at 15%. Secondary endpoints were progression-free survival, 6-month survival rate, overall survival, and toxicities. A total of 27 patients were enrolled from 7 hospitals. The median age was 67 years. Partial response was seen in 3 patients among the 26 evaluated patients. The overall response rate was at 11.5% (90% confidence interval 1.2%-21.8%). The median progression-free survival was 3.2 months, the 6-month survival rate was 85%, and the median overall survival was 11.6 months. Febrile neutropenia was observed in 14.8%. The most frequently observed grade 3 non-hematologic toxicity was anorexia (14.8%). The primary endpoint was not achieved. The results support a current consensus that the continuation of trastuzumab in second-line therapy for gastric cancer is not a recommended option.


Asunto(s)
Neoplasias de la Mama , Neoplasias Gástricas , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Docetaxel/uso terapéutico , Femenino , Humanos , Supervivencia sin Progresión , Neoplasias Gástricas/tratamiento farmacológico , Trastuzumab/uso terapéutico
11.
ESC Heart Fail ; 8(2): 1552-1561, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33547759

RESUMEN

AIMS: There is currently no gold standard in evaluating frailty in patients with heart failure (HF), and the prognostic value of frailty according to the Canadian Study of Health and Aging Clinical Frailty Scale (CFS) on mortality in patients with HF is still unknown. METHODS AND RESULTS: Among consecutive 596 patients after their discharge from HF in Kokura Memorial Hospital (Kitakyushu, Japan) during 2015, their frailty at discharge was assessed according to CFS. Patients were classified into three groups: low (N = 232, 38.9%), intermediate (N = 230, 38.6%), and high (N = 134, 22.5%). The primary endpoint was defined as 2 year all-cause death. The mean age was 76.6 ± 10.1 years, and 55.3% were men in entire cohort. There were significant differences in age, living environment, and dementia among low, intermediate, and high CFS groups. Left ventricular ejection fraction (LVEF) and co-morbidities such as severe renal failure and severe anaemia tended to increase with frailty severity, while body mass index (BMI) and albumin level tended to decrease with frailty severity. Two year cumulative incidences of all-cause death for the three groups were 12.8%, 25.4%, and 52.7% (P < 0.001), respectively. This significant difference in the risk for all-cause death among the CFS groups was driven by the risk for cardiac (8.6%, 14.2%, and 31.0%, respectively, P < 0.001) and non-cardiac death (4.6%, 13.0%, and 31.4%, respectively, P < 0.001). The multivariate analysis showed that high frailty was independently associated with all-cause death (intermediate CFS group: adjusted hazard ratio, 1.43, 95% confidence interval, 0.86-2.36, P = 0.16; high CFS group: adjusted hazard ratio, 3.90, 95% confidence interval, 2.32-6.55, P < 0.001), and this result was consistent, irrespective of stratification based on age, sex, BMI, and LVEF without significant interaction. CONCLUSIONS: The simple CFS tool was successful in predicting the risk for all-cause death in patients with HF, and frailty according to CFS was independently associated with all-cause death irrespective of stratification based on age, sex, BMI, and LVEF without significant interaction. The CFS is a valuable prognostic tool in clinical settings.


Asunto(s)
Fragilidad , Insuficiencia Cardíaca , Anciano , Anciano de 80 o más Años , Canadá , Anciano Frágil , Fragilidad/diagnóstico , Fragilidad/epidemiología , Insuficiencia Cardíaca/epidemiología , Humanos , Japón/epidemiología , Masculino , Volumen Sistólico , Función Ventricular Izquierda
12.
Int J Surg Case Rep ; 79: 307-311, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33497996

RESUMEN

INTRODUCTION: Although primary cystic duct cancer is a rare entity, remnant cystic duct cancer is even more rare. We report a case of early cystic duct cancer following cholecystectomy. PRESENTATION OF THE CASE: A 81 year-old man complained temporary loss of appetite. He had underwent cholecystectomy for acute cholecystitis 5 years prior. Contrast enhanced computed tomography, magnetic resonance image and endoscopic ultrasonography showed remnant cystic duct tumor with protrusion to common bile duct. Endoscopic retrograde cholangiography revealed defect of contrast medium around confluence of the remnant cystic duct and common bile duct. We performed step biopsy by using forceps which revealed adenocarcinoma. Based on these findings, extrahepatic bile duct and remnant cystic duct resection were performed. The histopathology showed adenocarcinoma, pap > tub2, filling in remnant cystic duct, 30 mm in size but showed no lymphovascular or perineural invasion, no lymph node metastasis and negative surgical margin, and was classified as pT1bN0M0. CONCLUSION: This is a rare case of primary carcinoma of remnant cystic duct cancer which is detected during computed tomography follow up for hepatic cell carcinoma recurrence. We confirmed remnant cystic duct cancer and its superficial extension to common bile duct with endoscopic ultrasonography and intraductal ultrasonography. Proper curative surgery was performed.

13.
J Clin Monit Comput ; 35(5): 1063-1068, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-32737750

RESUMEN

The Sensmart Model X-100 (Nonin Medical Inc, Plymouth, MN, USA) is a relatively new device that possesses two sets of emitters and detectors and uses near infrared spectroscopy (NIRS) to measure regional cerebral oxygen saturation (rSO2). The value of rSO2 obtained by other NIRS devices is affected by physiological and anatomical variables such as hemoglobin concentration, area of cerebrospinal fluid (CSF) layer and skull thickness. The effects of these variables have not yet been determined in measurement of rSO2 by Sensmart Model X-100. We examined the effects of area of CSF, hemoglobin concentration, and skull thickness on the values of rSO2 measured by Sensmart Model X-100 and tissue oxygen index (TOI) measured by NIRO-200NX (Hamamatsu Photonix, Hamamatsu, Japan). Forty neurosurgical, cardiac and vascular surgical patients who underwent preoperative computed tomographic (CT) scan of the brain were enrolled in this study. Regional cerebral oxygen saturation (rSO2) at the forehead was measured sequentially by NIRO-200NX and by Sensmart Model X-100. Simultaneously, mean arterial pressure, hemoglobin concentration, and partial pressure of carbon dioxide in arterial blood (PaCO2) were measured. To evaluate the effects of anatomical factors on rSO2, we measured skull thickness and area of CSF layer using CT images of the brain. Multiple regression analysis was used to examine the relationships between the rSO2 values and anatomical and physiological factors. The area of the CSF layer and hemoglobin concentration had significant associations with rSO2 measured by the Sensmart Model X-100, whereas none of the studied variables was significantly associated with TOI. The measurement of rSO2 by Sensmart Model X-100 is not affected by the skull thickness of patients. Area of the CSF layer and hemoglobin concentration may be the main biases in measurement of rSO2 by Sensmart Model X-100.


Asunto(s)
Oximetría , Espectroscopía Infrarroja Corta , Encéfalo , Humanos , Oxígeno , Cráneo/diagnóstico por imagen
14.
Intern Med ; 59(23): 3027-3032, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33268697

RESUMEN

Pancreatic neuroendocrine neoplasms occasionally have a cystic component. We herein report a case of multiple hepatic tumors, including a huge one and a 24-mm sized pancreatic cystic lesion. The hepatic tumor showed an enhancement pattern consistent with hepatic adenoma. The pancreatic cystic lesion revealed a thickened outside border and a solid inside component, which was enhanced following a contrast study, suggesting cystic pancreatic neuroendocrine neoplasm. Surgical resection was performed. After the surgery, somatostatin receptor scintigraphy detected an occult lumbar spine metastasis. Huge multiple liver and bone metastases of the neuroendocrine neoplasm G2 component were seen, with a G1 small primary lesion.


Asunto(s)
Neoplasias Óseas/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Vértebras Lumbares , Tumores Neuroendocrinos/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico por imagen , Adulto , Neoplasias Óseas/secundario , Endosonografía , Femenino , Humanos , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Imagen por Resonancia Magnética , Tomografía Computarizada Multidetector , Tumores Neuroendocrinos/patología , Tumores Neuroendocrinos/secundario , Tumores Neuroendocrinos/cirugía , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Tomografía de Emisión de Positrones , Somatostatina/análogos & derivados , Tomografía Computarizada por Rayos X
15.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 438-441, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33018022

RESUMEN

Automatically detecting and removing Electroencephalogram (EEG) outliers is essential to design robust brain-computer interfaces (BCIs). In this paper, we propose a novel outlier detection method that works on the Riemannian manifold of sample covariance matrices (SCMs). Existing outlier detection methods run the risk of erroneously rejecting some samples as outliers, even if there is no outlier, due to the detection being based on a reference matrix and a threshold. To address this limitation, our method, Riemannian Spectral Clustering (RiSC), detects outliers by clustering SCMs into non-outliers and outliers, based on a proposed similarity measure. This considers the Riemannian geometry of the space and magnifies the similarity within the non-outlier cluster and weakens it between non-outlier and outlier clusters, instead of setting a threshold. To assess RiSC performance, we generated artificial EEG datasets contaminated by different outlier strengths and numbers. Comparing Hit-False (HF) difference between RiSC and existing outlier detection methods confirmed that RiSC could detect outliers significantly better (p < 0.001). In particular, RiSC improved HF difference the most for datasets with the most severe outlier contamination.


Asunto(s)
Interfaces Cerebro-Computador , Algoritmos , Análisis por Conglomerados , Electroencefalografía
16.
Contemp Clin Trials Commun ; 16: 100489, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31799475

RESUMEN

The recommended phase 2 doses of molecularly targeted agents, determined by using an ordinal dose-finding method that only uses toxicity data at first cycle, may not be optimal. Some researchers have proposed the use of relative dose intensity that can account for late-onset, cumulative, and low-grade toxicities to determine the recommended phase 2 dose (RP2D). In this study, we proposed two dose escalation methods based on the observed relative dose intensities (RDIs) between the pre-specified intervals (cycles) for toxicity evaluation used in combination with DLT evaluation in the first cycle. First, we propose the modified 3 + 3 design that incorporates longitudinal RDI assessment. Second, we propose the sequential assessment method for longitudinal RDI (SARDI) to achieve faster dose escalation compared to that of the modified 3 + 3 design. Simulation studies demonstrated that the SARDI was, in many cases, superior to the ordinal and modified 3 + 3 designs in respect to the selection rate of true RP2D and study period. The two proposed methods could also in some cases decrease the average number of patients enrolled in the trial compared to that of the ordinary 3 + 3 design. Incorporation of the RDI assessment into the 3 + 3 design is not difficult and does not require the use of complex statistical techniques. Therefore, we believe that investigators who routinely use the 3 + 3 design in practice can easily use our proposed methods.

17.
Autops Case Rep ; 9(1): e2018068, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30863735

RESUMEN

There is scarce knowledge on early intestinal obstruction in Crohn's disease (CD) after infliximab treatment. Therefore, we describe two cases of early intestinal obstruction in a series of 46 CD patients treated with infliximab. Both our two cases were 21-year-old men with newly diagnosed CD who were diagnosed with perianal disease 2 years previously. They were suffering from diarrhea and abdominal pain, but there were no symptoms indicating bowel obstruction. Radiographic studies revealed stenotic sites in the terminal ileum in both cases. In both cases, infliximab 300 mg was infused, after which their abnormal laboratory data as well as symptoms such as diarrhea and abdominal pain clearly improved. However, on the 11th or 13th day post-treatment, they presented abdominal distension with air-fluid levels on imaging studies. Ileocolonic resection was performed in both cases. Early intestinal obstruction after infliximab therapy is characterized by initial improvement of the symptoms and the laboratory data, which is soon followed by clinical deterioration. This outcome indicates that infliximab is so swiftly effective that the healing process tapers the stenotic site, resulting in bowel obstruction. Thus, although unpleasant and severe, the obstruction cannot be considered as a side effect but rather a consequence of infliximab's efficacy. CD patients with intestinal stricture, particularly the penetrating type with stricture, should be well informed about the risk of developing intestinal obstruction after infliximab therapy and the eventual need for surgical intervention.

18.
Autops. Case Rep ; 9(1): e2018068, Jan.-Mar. 2019. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-987156

RESUMEN

There is scarce knowledge on early intestinal obstruction in Crohn's disease (CD) after infliximab treatment. Therefore, we describe two cases of early intestinal obstruction in a series of 46 CD patients treated with infliximab. Both our two cases were 21-year-old men with newly diagnosed CD who were diagnosed with perianal disease 2 years previously. They were suffering from diarrhea and abdominal pain, but there were no symptoms indicating bowel obstruction. Radiographic studies revealed stenotic sites in the terminal ileum in both cases. In both cases, infliximab 300 mg was infused, after which their abnormal laboratory data as well as symptoms such as diarrhea and abdominal pain clearly improved. However, on the 11th or 13th day post-treatment, they presented abdominal distension with air-fluid levels on imaging studies. Ileocolonic resection was performed in both cases. Early intestinal obstruction after infliximab therapy is characterized by initial improvement of the symptoms and the laboratory data, which is soon followed by clinical deterioration. This outcome indicates that infliximab is so swiftly effective that the healing process tapers the stenotic site, resulting in bowel obstruction. Thus, although unpleasant and severe, the obstruction cannot be considered as a side effect but rather a consequence of infliximab's efficacy. CD patients with intestinal stricture, particularly the penetrating type with stricture, should be well informed about the risk of developing intestinal obstruction after infliximab therapy and the eventual need for surgical intervention


Asunto(s)
Humanos , Masculino , Adulto , Enfermedad de Crohn/tratamiento farmacológico , Infliximab/efectos adversos , Obstrucción Intestinal/etiología , Infliximab/uso terapéutico
19.
Int J Mol Sci ; 20(1)2019 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-30621073

RESUMEN

Periodontal disease is chronic inflammation that leads to the destruction of tooth-supporting periodontal tissues. We devised a novel method ("cell transfer technology") to transfer cells onto a scaffold surface and reported the potential of the technique for regenerative medicine. The aim of this study is to examine the efficacy of this technique in periodontal regeneration and the fate of transplanted cells. Human periodontal ligament stem cells (PDLSCs) were transferred to decellularized amniotic membrane and transplanted into periodontal defects in rats. Regeneration of tissues was examined by microcomputed tomography and histological observation. The fate of transplanted PDLSCs was traced using PKH26 and human Alu sequence detection by PCR. Imaging showed more bone in PDLSC-transplanted defects than those in control (amnion only). Histological examination confirmed the enhanced periodontal tissue formation in PDLSC defects. New formation of cementum, periodontal ligament, and bone were prominently observed in PDLSC defects. PKH26-labeled PDLSCs were found at limited areas in regenerated periodontal tissues. Human Alu sequence detection revealed that the level of Alu sequence was not increased, but rather decreased. This study describes a novel stem cell transplantation strategy for periodontal disease using the cell transfer technology and offers new insight for cell-based periodontal regeneration.


Asunto(s)
Ligamento Periodontal/cirugía , Ligamento Periodontal/trasplante , Trasplante de Células Madre , Células Madre/citología , Adolescente , Adulto , Amnios/citología , Animales , Humanos , Ligamento Periodontal/diagnóstico por imagen , Ligamento Periodontal/patología , Ratas , Regeneración , Microtomografía por Rayos X , Adulto Joven
20.
NMC Case Rep J ; 5(2): 39-44, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29725566

RESUMEN

A 31-year-old man presented with a sudden-onset headache, right hemiparesis, and dysarthria on day 0 and was diagnosed with acute ischemic stroke due to dissection of the left intracranial internal carotid artery with middle cerebral artery extension. His symptoms progressed despite the institution of treatment, suggesting progression of the dissection. On day 5 after symptom onset, the patient underwent superficial temporal artery-middle cerebral artery anastomosis. No new ischemic stroke event occurred after surgery. Cerebral angiography performed 6 months after surgery showed spontaneous resolution of the dissection. The patient recovered to a modified Rankin Scale score of 2 and was able to return to work. The results of the present case suggest that superficial temporal artery-middle cerebral artery anastomosis is an effective treatment for ischemic stroke due to dissection of the intracranial internal carotid artery with middle cerebral artery extension.

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