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BACKGROUND: Current cardiovascular magnetic resonance sequences cannot discriminate between different myocardial extracellular space (ECSs), including collagen, noncollagen, and inflammation. We sought to investigate whether cardiovascular magnetic resonance radiomics analysis can distinguish between noncollagen and inflammation from collagen in dilated cardiomyopathy. METHODS: We identified data from 132 patients with dilated cardiomyopathy scheduled for an invasive septal biopsy who underwent cardiovascular magnetic resonance at 3 T. Cardiovascular magnetic resonance imaging protocol included native and postcontrast T1 mapping and late gadolinium enhancement (LGE). Radiomic features were computed from the midseptal myocardium, near the biopsy region, on native T1, extracellular volume (ECV) map, and LGE images. Principal component analysis was used to reduce the number of radiomic features to 5 principal radiomics. Moreover, a correlation analysis was conducted to identify radiomic features exhibiting a strong correlation (r>0.9) with the 5 principal radiomics. Biopsy samples were used to quantify ECS, myocardial fibrosis, and inflammation. RESULTS: Four histopathological phenotypes were identified: low collagen (n=20), noncollagenous ECS expansion (n=49), mild to moderate collagenous ECS expansion (n=42), and severe collagenous ECS expansion (n=21). Noncollagenous expansion was associated with the highest risk of myocardial inflammation (65%). Although native T1 and ECV provided high diagnostic performance in differentiating severe fibrosis (C statistic, 0.90 and 0.90, respectively), their performance in differentiating between noncollagen and mild to moderate collagenous expansion decreased (C statistic: 0.59 and 0.55, respectively). Integration of ECV principal radiomics provided better discrimination and reclassification between noncollagen and mild to moderate collagen (C statistic, 0.79; net reclassification index, 0.83 [95% CI, 0.45-1.22]; P<0.001). There was a similar trend in the addition of native T1 principal radiomics (C statistic, 0.75; net reclassification index, 0.93 [95% CI, 0.56-1.29]; P<0.001) and LGE principal radiomics (C statistic, 0.74; net reclassification index, 0.59 [95% CI, 0.19-0.98]; P=0.004). Five radiomic features per sequence were identified with correlation analysis. They showed a similar improvement in performance for differentiating between noncollagen and mild to moderate collagen (native T1, ECV, LGE C statistic, 0.75, 0.77, and 0.71, respectively). These improvements remained significant when confined to a single radiomic feature (native T1, ECV, LGE C statistic, 0.71, 0.70, and 0.64, respectively). CONCLUSIONS: Radiomic features extracted from native T1, ECV, and LGE provide incremental information that improves our capability to discriminate noncollagenous expansion from mild to moderate collagen and could be useful for detecting subtle chronic inflammation in patients with dilated cardiomyopathy.
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Cardiomiopatia Dilatada , Matriz Extracelular , Humanos , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/patologia , Matriz Extracelular/patologia , Matriz Extracelular/metabolismo , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Colágeno/metabolismo , Miocárdio/patologia , Idoso , Fibrose , Imageamento por Ressonância Magnética/métodos , Biópsia , Análise de Componente Principal , RadiômicaRESUMO
Human adenovirus (HAdV) infections present diverse clinical manifestations upon infecting individuals, with respiratory infections predominating in children. We surveyed pediatric hospitalizations due to respiratory HAdV infections across 18 hospitals in Hokkaido Prefecture, Japan, from July 2019 to March 2024, recording 473 admissions. While hospitalizations remained below five cases per week from July 2019 to September 2023, a notable surge occurred in late October 2023, with weekly admissions peaking at 15-20 cases from November to December. There were dramatic shifts in the age distribution of hospitalized patients: during 2019-2021, 1-year-old infants and children aged 3-6 years represented 51.4%-54.8% and 4.1%-13.3%, respectively; however, in 2023-2024, while 1-year-old infants represented 19.0%-20.1%, the proportion of children aged 3-6 years increased to 46.2%-50.0%. Understanding the emergence of significant outbreaks of respiratory HAdV infections and the substantial changes in the age distribution of hospitalized cases necessitates further investigation into the circulating types of HAdV in Hokkaido Prefecture and changes in children's neutralizing antibody titers against HAdV.
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Infecções por Adenovirus Humanos , Adenovírus Humanos , Surtos de Doenças , Hospitalização , Infecções Respiratórias , Humanos , Japão/epidemiologia , Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/virologia , Pré-Escolar , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Criança , Adenovírus Humanos/isolamento & purificação , Adenovírus Humanos/classificação , Masculino , Feminino , Hospitalização/estatística & dados numéricos , LactenteRESUMO
INTRODUCTION: Ovarian metastasis of colorectal cancer is known to have a poor prognosis. This study aimed to elucidate the characteristics of patients who underwent oophorectomy for ovarian metastasis from colorectal cancer. METHODS: This retrospective study included 16 patients who underwent oophorectomy for colorectal cancer metastasis to the ovary from January 2004 to December 2017. Improvement in patient's symptoms and pre- and postoperative changes in various nutritional and inflammatory indicators were assessed. Survival analysis and identification of prognostic factors were conducted with a median follow-up of 40.7 (5-109) months. RESULTS: Of 16 patients, 12 had (75%) synchronous and 4 (25%) had metachronous metastasis. Fourteen patients were symptomatic but symptoms resolved postoperatively. Thirteen patients (81.3%) had ascites and 5 (31.3%) had pleural effusion on preoperative computed tomography that disappeared after surgery in all cases. The median value of prognostic nutritional factor was significantly increased postoperatively (36.0 [preoperatively] vs. 47.5, p < 0.0001). The median (interquartile range) values for lymphocyte-C-reactive protein ratio were 715.2 (110-2,607) preoperatively and 6,095.2 (1,612.3-14,431.8) postoperatively (p = 0.0214). The median survival of the entire cohort was 60.4 months. The 3-year survival rates for R0 + R1 and R2 cases were 83% and 24% (p = 0.018), respectively. Univariate analysis showed that R2 resection and low postoperative lymphocyte-C-reactive protein ratio were associated with poor prognosis. CONCLUSIONS: Oophorectomy for ovarian metastasis from colorectal cancers was safely performed. It improved the patients' symptoms and nutritional status and may result in improved prognosis.
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Adenocarcinoma , Neoplasias Colorretais , Neoplasias Ovarianas , Feminino , Humanos , Neoplasias Ovarianas/cirurgia , Estudos Retrospectivos , Proteína C-Reativa , Estado Nutricional , Neoplasias Colorretais/patologia , Ovariectomia/métodos , Prognóstico , Adenocarcinoma/cirurgia , Adenocarcinoma/secundárioRESUMO
OBJECTIVES: This study aimed to investigate the relationship between microvascular status in the non-ischemic myocardium and the diagnostic performance of stress dynamic CT perfusion imaging (CTP) in detecting hemodynamically significant stenosis. MATERIALS AND METHODS: This study included 157 patients who underwent coronary computed tomography angiography (CTA), CTP, and invasive coronary angiography (ICA), including fractional flow reserve (FFR). Hemodynamically significant stenosis was defined by FFR and ICA. A relative myocardial blood flow (MBF) for each myocardial segment was normalized to the highest MBF (remote MBF) among 16 segments. RESULTS: The receiver operating characteristic curve analysis for detecting hemodynamically significant stenosis at the vessel level indicated that patients with lower, intermediate, and higher remote MBF had areas under the curve (AUC) of 0.66, 0.70, and 0.80, respectively, for absolute MBF and AUCs of 0.63, 0.70, and 0.83, respectively, for relative MBF. The optimal cut-off values for absolute MBF were proportional to the levels of remote MBFs, while the ones for relative MBF were more consistent across lower to higher remote MBFs. For the patients with high remote MBF, the relative MBF demonstrated a sensitivity of 69%, specificity of 88%, and accuracy of 85% in detecting hemodynamically significant stenosis. CONCLUSION: The microvascular status in the non-ischemic myocardium influenced the diagnostic performance of dynamic CTP and threshold values of absolute MBFs, suggesting the potential preference for relative MBF over absolute MBF in clinical settings. Dynamic CTP's quantification of MBF offers the benefit of indicating reliability in ischemia detection relative to microvascular status. KEY POINTS: Question The relationship between microvascular status and diagnostic performance of dynamic CTP imaging has not been fully investigated. Findings The diagnostic performance of dynamic CTP and threshold values of absolute MBF were impacted by microvascular status. Clinical relevance The differences in diagnostic accuracy of dynamic CTP related to varying remote MBF values necessitate a personalized evaluation of myocardial perfusion in dynamic CTP images.
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BACKGROUND AND OBJECTIVES: Robotic distal gastrectomy (RDG) has been widely performed throughout Japan since it became insured in 2018. This study aimed to evaluate the short-term outcomes of RDG and laparoscopic distal gastrectomy (LDG) for gastric cancer using real-world data. METHODS: A total of 4161 patients who underwent LDG (n = 3173) or RDG (n = 988) for gastric cancer between April 2018 and October 2022 were identified through the Japanese Diagnosis Procedure Combination Database, which covers 42 national university hospitals. The primary outcome was postoperative in-hospital mortality rate. The secondary outcomes were postoperative complication rates, time to diet resumption, and postoperative length of stay (LOS). RESULTS: In-hospital mortality and postoperative complication rates in the RDG group were comparable with those in the LDG group (0.1% vs. 0.0%, p = 1.000, and 8.7% vs. 8.2%, p = 0.693, respectively). RDG was associated with a longer duration of anesthesia (325 vs. 262 min, p < 0.001), similar time to diet resumption (3 vs. 3 days, p < 0.001), and shorter postoperative LOS (10 vs. 11 days, p < 0.001) compared with LDG. CONCLUSIONS: RDG was performed safely and provided shorter postoperative LOS, since it became covered by insurance in Japan.
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Laparoscopia , Procedimentos Cirúrgicos Robóticos , Neoplasias Gástricas , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Japão/epidemiologia , Pacientes Internados , Gastrectomia/métodos , Resultado do Tratamento , Laparoscopia/métodos , Complicações Pós-Operatórias/etiologia , Estudos RetrospectivosRESUMO
Treatment of esophageal cancer in the remnant esophagus after esophagectomy is highly invasive, therefore, early detection and minimally invasive treatment are considered necessary. Consequently, we aimed to clarify the safety and efficacy of endoscopic submucosal dissection (ESD) for residual esophageal cancer compared to that for esophageal cancer in a normal cervical esophagus. This study involved 47 patients with 59 residual esophageal cancers and 92 patients with 107 cervical esophageal cancers in normal esophagus who underwent ESD between January 2008 and December 2023. Their clinicopathological findings and long-term outcomes were retrospectively collected and evaluated. The median tumor diameter was 13 mm, and the median procedure time was 31 minutes in remnant esophagus group, with no significant difference between the two groups. No serious complications such as perforation, massive intraoperative bleeding, and pneumonia were observed in the remnant group, except for one case of postoperative bleeding. The rates of complete resection and disease specific survival were not significantly different between two groups, with complete resection rate of 86.4% and 5-year disease-specific survival rate of 95.7% in the remnant esophagus group. No local recurrence was observed during the median observation period of 43 months in the remnant esophagus group. ESD for superficial cancer of the remnant esophagus showed a high complete resection rate without serious complications and good local-regional control with no evidence of local recurrence. This indicates that ESD is a safe and useful treatment for superficial cancer of the remnant esophagus.
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This study investigates whether downstep in Japanese is directly triggered by accents. When the pitch height of a word X is lower after an accented word (A) than after an unaccented word (U), X is diagnosed as downstepped. However, this diagnosis involves two confounding factors: the already lowered F0 before X and phonological phrasing. To control these factors, this study contrasts genitive and nominative case markers and adjusts measurement points. Eight native speakers of Tokyo Japanese participated in a production experiment. The results show six key findings. First, a structure-dependent F0 downtrend was observed in UX. Second, higher F0 peaks with larger initial lowering were observed after accents with a nominative case marker compared to those with a genitive case marker, suggesting a boosting effect by boundaries. Third, larger initial lowering was observed in AX compared to UX, contradicting the notion that X is more compressed in AX due to downstep. Fourth, the paradigmatic difference in F0 height between AX and UX decreases when F0 of X is increased, supporting that boundaries trigger downstep. Fifth, downstep is not physiologically constrained but is phonologically controlled. Finally, the blocking of initial lowering in heavy syllables is not phonological but rather an articulatory phenomenon.
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Fonética , Acústica da Fala , Medida da Produção da Fala , Humanos , Masculino , Feminino , Adulto Jovem , Medida da Produção da Fala/métodos , Adulto , Qualidade da Voz , Percepção da FalaRESUMO
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.
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Fígado , Órgãos em Risco , Radiocirurgia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Respiração , Neoplasias da Coluna Vertebral , Humanos , Radiocirurgia/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Estudos Retrospectivos , Neoplasias da Coluna Vertebral/secundário , Neoplasias da Coluna Vertebral/radioterapia , Neoplasias da Coluna Vertebral/cirurgia , Masculino , Feminino , Radioterapia de Intensidade Modulada/métodos , Fígado/diagnóstico por imagem , Fígado/efeitos da radiação , Órgãos em Risco/efeitos da radiação , Idoso , Pessoa de Meia-Idade , Movimento , Tomografia Computadorizada por Raios X/métodos , Prognóstico , Idoso de 80 Anos ou maisRESUMO
BACKGROUND: Phase-contrast cine cardiovascular magnetic resonance (CMR) quantifies global coronary flow reserve (CFR) by measuring blood flow in the coronary sinus (CS), allowing assessment of the entire coronary circulation. However, the complementary prognostic value of stress perfusion CMR and global CFR in long-term follow-up has yet to be investigated. This study aimed to investigate the complementary prognostic value of stress myocardial perfusion imaging and global CFR derived from CMR in patients with suspected or known coronary artery disease (CAD) during long-term follow-up. METHODS: Participants comprised 933 patients with suspected or known CAD who underwent comprehensive CMR. Major adverse cardiac events (MACE) comprised cardiac death, non-fatal myocardial infarction, unstable angina, hospitalization for heart failure, stroke, ventricular arrhythmia, and late revascularization. RESULTS: During follow-up (median, 5.3 years), there were 223 MACE. Kaplan-Meier curve analysis revealed a significant difference in event-free survival among tertile groups for global CFR (log-rank, p < 0.001) and between patients with and without ischemia (p < 0.001). The combination of stress perfusion CMR and global CFR enhanced risk stratification (p < 0.001 for overall), and prognoses were comparable between the subgroup with ischemia and no impaired CFR and the subgroup with no ischemia and impaired CFR (p = 0.731). Multivariate Cox proportional hazard regression analysis showed that impaired CFR remained a significant predictor for MACE (hazard ratio, 1.6; p = 0.002) when adjusted for coronary risk factors and CMR predictors, including ischemia. The addition of impaired CFR to coronary risk factors and ischemia significantly increased the global chi-square value from 88 to 109 (p < 0.001). Continuous net reclassification improvement and integrated discrimination with the addition of global CFR to coronary risk factors plus ischemia improved to 0.352 (p < 0.001) and 0.017 (p < 0.001), respectively. CONCLUSIONS: During long-term follow-up, stress perfusion CMR and global CFR derived from CS flow measurement provided complementary prognostic value for prediction of cardiovascular events. Microvascular dysfunction or diffuse atherosclerosis as shown by impaired global CFR may play a role as important as that of ischemia due to epicardial coronary stenosis in the risk stratification of CAD patients.
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Doença da Artéria Coronariana , Imagem de Perfusão do Miocárdio , Humanos , Prognóstico , Estudos de Coortes , Imagem Cinética por Ressonância Magnética/métodos , Valor Preditivo dos Testes , Imagem de Perfusão do Miocárdio/métodos , Espectroscopia de Ressonância Magnética , Fatores de Risco , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Medição de RiscoRESUMO
It has been shown that a group of rectal cancer patients will achieve a pathological complete response following preoperative chemoradiotherapy, and non-operative management has recently gained attention. To escalate the tumour dose and increase the likelihood of pathological complete response, brachytherapy can play an important role in safely increasing the total dose. However, at the time this report was published, an applicator dedicated to rectal brachytherapy was unaffordable in Japan. Here, we report two T3 rectal cancer patients who were inoperable or refused surgery and treated by chemoradiotherapy following intracavitary brachytherapy involving a vaginal cylinder applicator with lead shielding.
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Braquiterapia , Neoplasias Retais , Feminino , Humanos , Neoplasias Retais/radioterapia , Reto , Quimiorradioterapia , Dosagem RadioterapêuticaRESUMO
Currently, tongue cancers are primarily managed by surgery, and interstitial brachytherapy is only recommended for a selected group of early state T1-2N0 patients who refuse surgery or are medically inoperable. In this report, a case with T3N2cM0 tongue cancer who has been effectively treated by the combination of concurrent chemoradiotherapy involving volumetric arc therapy and boost high-dose rate interstitial brachytherapy is presented. Of course, surgery remains the main treatment strategy for tongue cancer patients; however, the authors believe that if volumetric arc therapy is carefully planned to reduce the mandible dose as much as possible and high-dose rate interstitial brachytherapy with a mouthpiece that protects the mandible is combined, it is possible to treat T3N2 disease, and this can be considered for patients who want to preserve organ function.
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Braquiterapia , Neoplasias da Língua , Humanos , Braquiterapia/efeitos adversos , Neoplasias da Língua/radioterapia , Dosagem Radioterapêutica , Cabeça , QuimiorradioterapiaRESUMO
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.
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Hemangiossarcoma , Humanos , Hemangiossarcoma/radioterapia , Hemangiossarcoma/patologia , Couro Cabeludo/patologia , Estudos Retrospectivos , Relevância Clínica , Qualidade de Vida , DorRESUMO
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.
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Planejamento da Radioterapia Assistida por Computador , Irradiação Corporal Total , Humanos , Imagens de Fantasmas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodosRESUMO
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.
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Planejamento da Radioterapia Assistida por Computador , Humanos , Movimento (Física) , Espectroscopia de Ressonância Magnética , Dosagem Radioterapêutica , Imagens de FantasmasRESUMO
The development of self-healing systems for artificial superhydrophobic materials/surfaces based on the reconstruction of surface topologies rather than chemical makeup has been much less established. In this article, we report for the first time a simple and straightforward method for self-repairing surface dewettability over a long period of time by rapidly regenerating surface microstructures. We selected paraffin wax as a matrix for methyltrichlorosilane (MTCS) having strong reactivity with moisture/water and simply mixed them. When the as-prepared MTCS-loaded paraffin wax surfaces were exposed to air for a few hours, they spontaneously became highly hydrophobic with water contact angles of about 150° due to the formation of disordered surface microstructures. The use of paraffin wax with a few angstrom-scale space as a matrix was found to be more effective than the use of poly(dimethylsiloxane) with nanometer-size porosity in preventing both evaporation and degradation of MTCS's chemical reactivity for a long period. Therefore, for about 1 month, even after the surface microstructures were completely destroyed, surface dewettability could be self-repaired by rapidly regenerating surface morphologies. In addition, chemical damage by UV/ozone exposure could also be repeatably self-healed by the reconstruction of surface chemical makeup. We thus expect that this simple approach could provide future insights to impart the self-healing ability of manmade superhydrophobic materials/surfaces against chemical and physical damages.
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Accumulations of ice on modern infrastructures often cause severe consequences. As such, there is significant interest in developing functional coatings/surfaces that can prevent this. One such approach has been demonstrated with slippery liquid-infused porous surfaces (SLIPS) and organogels where the ice adhesion strength is reduced to the critical point (less than 10 kPa) where it can be removed by natural forces such as gravity, wind, vibrations, and so forth. However, both designs are limited by lubricant depletion. If lubricant release and reabsorption (syneresis) of organogels can be arbitrarily controlled by the surrounding temperature, the loss due to unfavorable evaporation and drainage of infused lubricants can be minimized and its durability can be extended. This study demonstrates the tunable thermo-responsive syneresis of transparent fluorinated organogels (F-ORGs) prepared from a commercial silicone elastomer and a lubricant mixture of fluorinated silicone oil and either poly(dimethylsiloxane) or poly(methylphenylsiloxane). By carefully tuning the ratio of the two lubricants in the mixture, the corresponding F-ORGs demonstrated arbitrarily tunable critical syneresis temperatures from -15 to 40 °C, below which the lubricant is released on the surface and above which the lubricant is re-absorbed. The resulting surfaces showed not only exceptionally long-lasting/repeatable low ice adhesion strengths (≤10 kPa over 50 icing/de-icing cycles) but also significant improvements in their repellency toward a variety of organic liquids. Compared to non-fluorinated organogels, F-ORGs could offer improved protection against outdoor pollutants to further enhance their practicality.
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Corn xylan is resistant to enzymatic hydrolysis due to its complex structure. We characterized PsXyn5A, an enzyme highly active for corn xylan, isolated from Paenibacillus sp. H2C. PsXyn5A is a modular xylanase with a catalytic domain belonging to the glycoside hydrolase family 5 subfamily 35 (GH5_35) and a carbohydrate-binding module family 13 (CBM13) domain. The substrate recognition mechanism of GH5_35 xylanase has not been reported. Analysis of the hydrolysate from rye arabinoxylan (RAX) has shown that the GH5_35 catalytic domain of PsXyn5A recognizes an arabinofuranosyl (Araf) side residue and cleaves the reducing terminal side of Araf-linked xylopyranose. This cleavage specificity is the same as reported for the GH5_34 xylanase from Hungateiclostridium thermocellum (HtXyl5A). Unlike HtXyl5A, PsXyn5A produced Araf-xylopyranose from RAX and did not hydrolyze 33-α-l-Araf-xylotetraose. Deletion of the CBM13 domain significantly decreased the activity toward insoluble corn xylan, indicating that CBM13 plays an essential role in hydrolyzing corn xylan.
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Paenibacillus , Xilanos , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Paenibacillus/genética , Domínio Catalítico , Especificidade por Substrato , Endo-1,4-beta-Xilanases/químicaRESUMO
BACKGROUND: The black soldier fly (Hermetia illucens) is the most promising insect candidate for nutrient-recycling through bioconversion of organic waste into biomass, thereby improving sustainability of protein supplies for animal feed and facilitating transition to a circular economy. Contrary to conventional livestock, genetic resources of farmed insects remain poorly characterised. We present the first comprehensive population genetic characterisation of H. illucens. Based on 15 novel microsatellite markers, we genotyped and analysed 2862 individuals from 150 wild and captive populations originating from 57 countries on seven subcontinents. RESULTS: We identified 16 well-distinguished genetic clusters indicating substantial global population structure. The data revealed genetic hotspots in central South America and successive northwards range expansions within the indigenous ranges of the Americas. Colonisations and naturalisations of largely unique genetic profiles occurred on all non-native continents, either preceded by demographically independent founder events from various single sources or involving admixture scenarios. A decisive primarily admixed Polynesian bridgehead population serially colonised the entire Australasian region and its secondarily admixed descendants successively mediated invasions into Africa and Europe. Conversely, captive populations from several continents traced back to a single North American origin and exhibit considerably reduced genetic diversity, although some farmed strains carry distinct genetic signatures. We highlight genetic footprints characteristic of progressing domestication due to increasing socio-economic importance of H. illucens, and ongoing introgression between domesticated strains globally traded for large-scale farming and wild populations in some regions. CONCLUSIONS: We document the dynamic population genetic history of a cosmopolitan dipteran of South American origin shaped by striking geographic patterns. These reflect both ancient dispersal routes, and stochastic and heterogeneous anthropogenic introductions during the last century leading to pronounced diversification of worldwide structure of H. illucens. Upon the recent advent of its agronomic commercialisation, however, current human-mediated translocations of the black soldier fly largely involve genetically highly uniform domesticated strains, which meanwhile threaten the genetic integrity of differentiated unique local resources through introgression. Our in-depth reconstruction of the contemporary and historical demographic trajectories of H. illucens emphasises benchmarking potential for applied future research on this emerging model of the prospering insect-livestock sector.
Assuntos
Dípteros , Ração Animal/análise , Animais , Demografia , Dípteros/genética , Genética Populacional , Humanos , LarvaRESUMO
Skeletal muscle is known to regulate bone homeostasis through muscle-bone interaction, although factors that control this activity remain unclear. Here, we newly established Smad3-flox mice, and then generated skeletal muscle-specific Smad2/Smad3 double conditional knockout mice (DcKO) by crossing Smad3-flox with skeletal muscle-specific Ckmm Cre and Smad2-flox mice. We show that immobilization-induced gastrocnemius muscle atrophy occurring due to sciatic nerve denervation was partially but significantly inhibited in DcKO mice, suggesting that skeletal muscle cell-intrinsic Smad2/3 is required for immobilization-induced muscle atrophy. Also, tibial bone atrophy seen after sciatic nerve denervation was partially but significantly inhibited in DcKO mice. Bone formation rate in wild-type mouse tibia was significantly inhibited by immobilization, but inhibition was abrogated in DcKO mice. We propose that skeletal muscle regulates immobilization-induced bone atrophy via Smad2/3, and Smad2/3 represent potential therapeutic targets to prevent both immobilization-induced bone and muscle atrophy.
Assuntos
Músculo Esquelético/metabolismo , Atrofia Muscular/genética , Atrofia Muscular/prevenção & controle , Nervo Isquiático/lesões , Proteína Smad2/genética , Proteína Smad3/genética , Animais , Cruzamentos Genéticos , Feminino , Regulação da Expressão Gênica , Integrases/genética , Integrases/metabolismo , Masculino , Camundongos , Camundongos Knockout , Denervação Muscular/métodos , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Músculo Esquelético/inervação , Músculo Esquelético/patologia , Atrofia Muscular/metabolismo , Atrofia Muscular/patologia , Proteínas Ligases SKP Culina F-Box/genética , Proteínas Ligases SKP Culina F-Box/metabolismo , Transdução de Sinais , Proteína Smad2/deficiência , Proteína Smad3/deficiência , Tíbia/inervação , Tíbia/metabolismo , Proteínas com Motivo Tripartido/genética , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismoRESUMO
Estrogen deficiency can be caused by ovarian dysfunction in females. Mechanisms underlying osteoporosis in this condition have been characterized in animal models, such as ovariectomized mice and rats, although it remains unclear how hypothalamic dysfunction promotes osteoporosis. Here, we show that administration of a gonadotropin-releasing hormone antagonist (GnRHa) significantly decreases uterine weight, a manifestation of hypothalamic dysfunction, and promotes both cortical and trabecular bone loss in female mice in vivo. We also report that osteoclast number significantly increased in mice administered GnRHa, and that the transcription factor hypoxia inducible factor 1 alpha (HIF1α) accumulated in those osteoclasts. We previously reported that treatment of mice with the active vitamin D analogue ED71, also known as eldecalcitol, inhibited HIF1α accumulation in osteoclasts. We show here that in mice, co-administration of ED71 with GnRHa significantly rescued the reduced cortical and trabecular bone mass promoted by GnRHa administration alone. GnRHa-dependent HIF1α accumulation in osteoclasts was also blocked by co-administration of ED71. We conclude that hypothalamic dysfunction promotes HIF1α accumulation in osteoclasts and likely results in reduced bone mass. We conclude that treatment with ED71 could serve as a therapeutic option to counter osteoporotic conditions in humans.