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1.
J Appl Clin Med Phys ; 25(7): e14342, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38590112

RESUMEN

BACKGROUND: Rescanning is a common technique used in proton pencil beam scanning to mitigate the interplay effect. Advances in machine operating parameters across different generations of particle therapy systems have led to improvements in beam delivery time (BDT). However, the potential impact of these improvements on the effectiveness of rescanning remains an underexplored area in the existing research. METHODS: We systematically investigated the impact of proton machine operating parameters on the effectiveness of layer rescanning in mitigating interplay effect during lung SBRT treatment, using the CIRS phantom. Focused on the Hitachi synchrotron particle therapy system, we explored machine operating parameters from our institution's current (2015) and upcoming systems (2025A and 2025B). Accumulated dynamic 4D dose were reconstructed to assess the interplay effect and layer rescanning effectiveness. RESULTS: Achieving target coverage and dose homogeneity within 2% deviation required 6, 6, and 20 times layer rescanning for the 2015, 2025A, and 2025B machine parameters, respectively. Beyond this point, further increasing the number of layer rescanning did not further improve the dose distribution. BDTs without rescanning were 50.4, 24.4, and 11.4 s for 2015, 2025A, and 2025B, respectively. However, after incorporating proper number of layer rescanning (six for 2015 and 2025A, 20 for 2025B), BDTs increased to 67.0, 39.6, and 42.3 s for 2015, 2025A, and 2025B machine parameters. Our data also demonstrated the potential problem of false negative and false positive if the randomness of the respiratory phase at which the beam is initiated is not considered in the evaluation of interplay effect. CONCLUSION: The effectiveness of layer rescanning for mitigating interplay effect is affected by machine operating parameters. Therefore, past clinical experiences may not be applicable to modern machines.


Asunto(s)
Neoplasias Pulmonares , Fantasmas de Imagen , Terapia de Protones , Radiocirugia , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Humanos , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirugía , Radiocirugia/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Terapia de Protones/métodos , Radioterapia de Intensidad Modulada/métodos , Órganos en Riesgo/efectos de la radiación
2.
Biomed Eng Online ; 22(1): 57, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37316944

RESUMEN

OBJECTIVE: To investigate the effectiveness of using a 3D-printed total skin bolus in total skin helical tomotherapy for the treatment of mycosis fungoides. MATERIALS AND METHODS: A 65-year-old female patient with a 3-year history of mycosis fungoides underwent treatment using an in-house desktop fused deposition modelling printer to create a total skin bolus made of a 5-mm-thick flexible material, which increased the skin dose through dose building. The patient's scan was segmented into upper and lower sections, with the division line placed 10 cm above the patella. The prescription was to deliver 24 Gy over 24 fractions, given 5 times per week. The plan parameters consisted of a field width of 5 cm, pitch of 0.287 and modulation factor of 3. The complete block was placed 4 cm away from the planned target region to reduce the area of the internal organs at risk, especially the bone marrow. Dose delivery accuracy was verified using point dose verification with a "Cheese" phantom (Gammex RMI, Middleton, WI), 3D plane dose verification with ArcCHECK (Model 1220, Sun Nuclear, Melbourne, FL), and multipoint film dose verification. Megavoltage computed tomography guidance was also utilized to ensure the accuracy of the setup and treatment. RESULTS: A 5-mm-thick 3D-printed suit was used as a bolus to achieve a target volume coverage of 95% of the prescribed dose. The conformity index and homogeneity index of the lower segment were slightly better than those of the upper segment. As the distance from the skin increased, the dose to the bone marrow gradually decreased, and the dose to other organs at risk remained within clinical requirements. The point dose verification deviation was less than 1%, the 3D plane dose verification was greater than 90%, and the multipoint film dose verification was less than 3%, all of which confirmed the accuracy of the delivered dose. The total treatment time was approximately 1.5 h, which included 0.5 h of wearing the 3D-printed suit and 1 h with the beam on. Patients only experienced mild fatigue, nausea or vomiting, low-grade fever, and grade III bone marrow suppression. CONCLUSION: The use of a 3D-printed suit for total skin helical tomotherapy can result in a uniform dose distribution, short treatment time, simple implementation process, good clinical outcomes, and low toxicity. This study presents an alternative treatment approach that can potentially yield improved clinical outcomes for mycosis fungoides.


Asunto(s)
Micosis Fungoide , Radioterapia de Intensidad Modulada , Neoplasias Cutáneas , Femenino , Humanos , Anciano , Piel , Impresión Tridimensional
3.
Altern Ther Health Med ; 29(4): 164-169, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36933248

RESUMEN

Context: Chronic renal failure (CRF) is the outcome of the continuous progression of various chronic kidney diseases. Effective treatment of a wide range of diseases may require decreasing patients' negative emotions and enhancing their disease resilience. Narrative care focuses on patients' inner awareness, feelings, and experience of a disease, stimulating positive energy in the face of it. Objective: The study intended to investigate the effects of using narrative care during high flux hemodialysis (HFHD) on clinical outcomes and prognosis of quality of life (QoL) for patients with chronic renal failure (CRF), to provide a reliable theoretical reference for future clinical treatment. Design: The research team performed a randomized controlled trial. Setting: The study took place at the Blood Purification Center at the Affiliated Hospital of Medical School at Ningbo University in Ningbo, Zhejiang, China. Participants: Participants were 78 patients with CRF who received treat with HFHD at the hospital between January 2021 and August 2022. Intervention: The research team divided participants into two groups using the random number table method, with 39 participants in each group: (1) and intervention group who received narrative nursing care and (2) a control group who receive the usual care. Outcome Measures: The research team: (1) evaluated the clinical efficacy for both groups; (2) at baseline and postintervention, measured participants' blood creatinine (SCr) and blood urea nitrogen (BUN) using blood sampling; (3) counted adverse effects; (4) investigated participants' nursing satisfaction postintervention; (5) at baseline and postintervention, assessed psychology and QoL using the Self-Assessment Scale for Anxiety (SAS), the Self-Assessment Scale for Depression (SDS), and the General Quality of Life Inventory (GQOLI-74) scale. Results: No statistically significant differences existed between the groups in terms of efficacy or renal function postintervention (P > .05). The incidence of adverse reactions was significantly lower in the intervention group than in the control group postintervention (P = .033), and the group's nursing satisfaction was significantly higher (P = .042). In addition, participants' SAS and SDS scores decreased significantly in the intervention group postintervention (P < .05), while no change occurred for the control group (P > .05). Finally, the GQOLI-74 scores were all significantly higher in the intervention group than in the control group. Conclusions: Narrative care can effectively enhance the safety of HFHD treatment in CRF patients and reduce patients' negative emotions postintervention, which is important for improving their QoL.


Asunto(s)
Fallo Renal Crónico , Calidad de Vida , Humanos , Pronóstico , Fallo Renal Crónico/terapia , Diálisis Renal , Resultado del Tratamiento
4.
Inorg Chem ; 61(34): 13453-13461, 2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-35969492

RESUMEN

It is a challenge to fabricate atomically dispersed metal clusters in polymeric carbon nitride (PCN) for durable photocatalytic reactions owing to the thermodynamic stability limitation. Herein, atomically dispersed Ru clusters are implanted into the PCN skeleton matrix based on an ionic diffusion and coordination (IDC) strategy, the stability of which is improved owing to the robust Ru-N bonds in the formed RuN4 and RuN3 configurations. Additionally, RuN4 and RuN3 as charge transport bridges between two adjacent melon strands efficaciously conquer hydrogen bond restriction in the skeleton to facilitate the in-plane mobility and separation of charge carriers. Moreover, the synergistic effect of adjacent Ru atoms is triggered on the assembled RuN3-RuN4 and RuN3-RuN3 in the atomically dispersed Ru clusters to significantly decrease hydrogen adsorption energy. As a result, the optimal PCN-Ru photocatalyst achieves nearly 6 times higher than the photocatalytic hydrogen evolution (PHE) rate of the Pt/PCN benchmark and maintains the long-term stable running for 104 h of 26 cycles; its overall PHE performance is far superior to the most of single atoms supported on g-C3N4 photocatalysts reported. The findings here gain new insight into the preparation strategy, structure configuration, and reaction mechanism for atomically dispersed metal clusters supported on PCN, which further stimulates the intensive investigations toward developing more efficient and stable PCN-like photocatalytic materials.

5.
BMC Womens Health ; 22(1): 470, 2022 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-36434592

RESUMEN

BACKGROUND: Pentamidine has been reported to have many pharmacological effects including anti- protozoal, anti-inflammatory, and anti-tumor activities. The aim of this study is to investigate the potential therapeutic role of Pentamidine and molecular mechanisms of Pentamidine on PI3K/AKT signaling pathway underlying the anti-tumor properties in endometrial cancer. METHODS: Our study was carried out in the central laboratory of Harbin Medical University from 2019 to 2021. Human endometrial cancer cell lines Ishikawa and HEC-1A were treated with Pentamidine. The proliferation ability of cells was investigated by MTS and colony formation assays. The cell cycle distribution was detected by flow cytometry. Cell migration and invasion were analyzed by using the wound healing assay and Transwell assay. Western blotting was performed to measure the levels of AKT, p-AKT, MMP-2, and MMP-9. RESULTS: Our results revealed that treatment of Pentamidine inhibited proliferation, migration and invasion of Ishikawa and HEC-1A endometrial cancer cells. Mechanistic investigation showed that Pentamidine inhibited PI3K/AKT signaling pathway and also reduced the expression of MMP-2 and MMP-9. In addition, co-treatment with PI3K kinase inhibitor LY294002 and Pentamidine leaded to increased repression of cell viability and the protein expression of p-AKT in Ishikawa cells. CONCLUSIONS: Pentamidine suppresses PI3K/AKT signaling pathway, and inhibits proliferation, migration and invasion of EC cells. These findings suggested that Pentamidine might be a potential candidate for treating EC through PI3K/AKT pathway.


Asunto(s)
Neoplasias Endometriales , Fosfatidilinositol 3-Quinasas , Femenino , Humanos , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositol 3-Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/uso terapéutico , Pentamidina/farmacología , Pentamidina/uso terapéutico , Proliferación Celular , Transducción de Señal , Neoplasias Endometriales/patología
6.
Altern Ther Health Med ; 28(8): 30-37, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35839110

RESUMEN

Context: Slow transit constipation (STC) has a high incidence worldwide, which not only seriously affects patients' normal lives but also may cause malignant intestinal lesions. Among the limited treatment options for STC, traditional Chinese medicine (TCM) is considered to be the key to STC treatment in the future. Objective: The study intended to examine the impacts of acupuncture plus acupoint application on MAPK and ERK in STC rats, with the aim of preliminarily exploring the relevant mechanisms for treating STC as well as providing new ideas and means for future clinical treatment. Design: The research team designed a randomized, controlled animal study. Setting: The study was carried out at department of Department of Rehabilitation, Affiliated Hospital of Medical School of Ningbo University, Ningbo, Zhejiang, China. Animals: The animals were 30 six-to-eight-week-old, Sprague Dawley (SD) rats, half male and half female and weighing a mean of 200 ± 20 g. Intervention: The rats were randomly assigned to one of three groups, 10 rats in each group: a negative control group that wasn't induced with STC and received no treatments; a positive control group, the model group (MG), that was induced with STC and received no treatments; and an intervention group that was induced with STC and received the investigated treatments. The intervention group was treated with acupuncture at Tianshu point (ST25) and received acupoint application from Chinese medicine. Outcome Measures: The study measured the alterations in the rats' body weight and feces, as well as the rats' intestinal motility, using intragastric administration of activated carbon. The rats were killed to obtain their intestinal tissues, for measuring expression of mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinase (ERK) using Western blotting and polymerase chain reaction (PCR). Results: Postintervention, at 28 days after induction of STC, the rats' weights weren't significantly different in the intervention and control groups (P > .05) but were significantly higher than that in the model group (P < .05). The rats' weights in the intervention and control groups gradually increased significantly, while those in the model group gradually decreased significantly (P < .05). The defecation volume and fecal water content (FWS) decreased in the significantly model group but increased significantly in the intervention group (P < .05). The intestinal motility test revealed no significant differences in the propulsion rate between the intervention and control groups (P > .05), but the rate was significantly lower in the model group than that of the intervention group (P < .05). The intestinal fecal residue in the model group was the highest among the three groups, followed in descending order by the intervention group and the control group, with the differences being statistically significant (P < .05). In addition, the MAPK and ERK in the model group significantly increased, and the values were significantly higher in the intervention group than those of the model group (P < .05). Conclusions: Acupuncture plus acupoint application can validly improve the defecation and intestinal motility of STC rats, possibly through inhibiting MAPK and ERK.


Asunto(s)
Puntos de Acupuntura , Terapia por Acupuntura , Ratas , Masculino , Femenino , Animales , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Ratas Sprague-Dawley , Colon/metabolismo , Colon/patología , Estreñimiento/terapia
7.
J Appl Clin Med Phys ; 23(4): e13527, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35060317

RESUMEN

PURPOSE: To evaluate the relative biological effectiveness (RBE)-weighted dose to the heart and to estimate RBE uncertainties when assuming a constant RBE of 1.1, for breast cancer patients receiving intensity-modulated proton therapy (IMPT). Further, to study the impact of RBE uncertainties on the risk of an acute coronary event (ACE). MATERIAL AND METHODS: We analyzed 20 patients who received IMPT to either the left breast (n = 10) or left chest wall (n = 10) and regional lymph nodes. The Monte Carlo simulation engine, MCsquare, was used to simulate the dose-averaged linear energy transfer (LETd) map. The RBE-weighted dose to the heart and its substructures was calculated using three different RBE models. The risk of ACE was estimated per its linear relationship with mean heart dose (MHD) as established by Darby et al. RESULTS: The median MHD increased from 1.33 GyRBE assuming an RBE of 1.1 to 1.64, 1.87, and 1.99 GyRBE when using the RBE-weighted dose models. The median values (and ranges) of the excess absolute risk of ACE were 0.4% (0.1%-0.8%) when assuming an RBE of 1.1, and 0.6% (0.2%-1.0%), 0.6% (0.2%-1.1%), and 0.7% (0.2%-1.1%) with the RBE-weighted models. For our patient cohort, the maximum excess absolute risk of ACE increased by 0.3% with the RBE-weighted doses compared to the constant RBE of 1.1, reaching an excess absolute ACE risk of 1.1%. The interpatient LETd variation was small for the relevant high-dose regions of the heart. CONCLUSION: All three RBE models predicted a higher biological dose compared to the clinical standard dose assuming a constant RBE of 1.1. An underestimation of the biological dose results in underestimation of the ACE risk. Analyzing the voxel-by-voxel biological dose and the LET map alongside clinical outcomes is warranted in the development of a more accurate normal-tissue complication probability model.


Asunto(s)
Neoplasias de la Mama , Terapia de Protones , Radioterapia de Intensidad Modulada , Neoplasias de la Mama/radioterapia , Femenino , Humanos , Terapia de Protones/efectos adversos , Terapia de Protones/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos , Efectividad Biológica Relativa
8.
BMC Surg ; 22(1): 187, 2022 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-35568840

RESUMEN

BACKGROUND: The purpose of this retrospective study was to investigate the risk factors for intraoperative acute diffuse brain swelling in patients with isolated traumatic acute subdural haematomas (ASDH). METHODS: A total of 256 patients who underwent decompressive craniectomy for isolated traumatic ASDH between April 2013 and December 2020 were included. We evaluated the risk factors for intraoperative acute diffuse brain swelling using a multivariate logistic regression analysis. RESULTS: The incidence of intraoperative acute diffuse brain swelling in patients with isolated traumatic ASDH was 21.88% (56/256). Dilated pupils (OR = 24.78), subarachnoid haemorrhage (OR = 2.41), and the time from injury to surgery (OR = 0.32) were independent risk factors for intraoperative acute diffuse brain swelling, while no independent associations were observed between these risk factors and sex, age, the mechanism of injury, the Glasgow Coma Scale score, site of haematoma, thickness of haematoma, midline shift and the status of the basal cistern, although the mechanism of injury, the Glasgow Coma Scale score and the status of the basal cistern were correlated with the incidence of intraoperative acute diffuse brain swelling in the univariate analyses. CONCLUSIONS: This study identified the risk factors for intraoperative acute diffuse brain swelling in patients with isolated traumatic ASDH. An increased risk of intraoperative acute diffuse brain swelling occurs in patients with bilaterally dilated pupils, subarachnoid haemorrhage and a shorter time from injury to surgery. These findings should help neurosurgeons obtain information before surgery about intraoperative acute diffuse brain swelling in patients with isolated traumatic ASDH.


Asunto(s)
Edema Encefálico , Hematoma Subdural Agudo , Hemorragia Subaracnoidea , Escala de Coma de Glasgow , Hematoma Subdural Agudo/etiología , Hematoma Subdural Agudo/cirugía , Humanos , Estudios Retrospectivos , Factores de Riesgo , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/cirugía , Resultado del Tratamiento
9.
Mikrochim Acta ; 189(12): 467, 2022 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-36422716

RESUMEN

A selective method for the determination of myosmine (a tobacco alkaloid) was developed using molecularly imprinted polymers (MIPs) based on Fe3O4@SiO2 and PAMAM dendrimers. Fe3O4@SiO2 with excellent magnetism and rapid separation performance was chosen as carrier for the MIPs. Moreover, the MIPs modified with PAMAM dendrimers exhibited a regular structure and abundant functional groups, which improve the efficiency of imprinting sites. The myosmine concentration was measured by HPLC with PDA detector, and the UV detection wavelength was set to 200 nm. The linear range of this assay was 13.2-400 mg/L with a correlation coefficient of 0.999, and the detection limit was 4.0 mg/L (S/N = 3). The MIPs have been used for the determination of myosmine in cigarettes, and the recovery range was 84.2-93.5%, with RSD values in the range 0.41-3.1%. In conclusion, our MIPs combine advantages of simple preparation and remarkable selectivity, which gives them excellent application prospects for the sensitive determination of trace myosmine in tobacco products.


Asunto(s)
Alcaloides , Dendrímeros , Impresión Molecular , Productos de Tabaco , Polímeros Impresos Molecularmente , Impresión Molecular/métodos , Dióxido de Silicio/química , Polímeros/química
10.
J Environ Manage ; 304: 114260, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34915386

RESUMEN

The polyvinylidene difluoride (PVDF) membrane has received considerable attention as a flexible surface enhanced Raman scattering (SERS) substrate due to its excellent mechanical and physicochemical properties. However, the poor fouling resistance of PVDF membrane due to its intrinsic hydrophobic property limits its practical application. To address this, in this investigation, a SERS imprinted membrane is synthesized based on W18O49/Ag composites. Firstly, to promote hydrophilicity, N-vinyl-2-pyrrolidone (NVP) and triethoxyvinylsilane (VTES) are copolymerized by hydrolysis condensation and linked with engineered polyvinypyrrolidone (PVP) chains exposed on the surface of membrane. Furthermore, W18O49/Ag composites are dispersed on the membrane under the assistance of polydopamine (pDA) to promote the pollution resistance. Subsequently, in order to demonstrate the practical detection property, W18O49/Ag/PVDF membrane is selected as the SERS substrate to synthesize SERS imprinted membrane by precipitation polymerization for the selective detection of L-tyrosine. The characteristic results reveal that the SERS-imprinted membrane exhibits satisfactory hydrophilicity, and it can effectively degrade the pollutant molecules absorbed on its surface under ultraviolet light illumination. It is proved from the detection results that the LOD of WADP-MIMs for L-tyrosine reached 10-9 mol L-1 when the concentration of L-tyrosine changed between 10-3-10-9 mol L-1. The correlation coefficient (R2) is 0.994 and the limit of detection is 10-9 mol L-1. Meanwhile, it can be applied for the selective detection of L-tyrosine in mixture samples. Overall, this study presents a novel approach for the hydrophilic modification and pollution resistance enhancement of PVDF-based SERS imprinted membrane, which can be effectively utilized for the selective detection of practical samples.


Asunto(s)
Polivinilos , Tirosina , Polímeros de Fluorocarbono , Interacciones Hidrofóbicas e Hidrofílicas , Espectrometría Raman
11.
Small ; 17(39): e2102539, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34405940

RESUMEN

Improving greatly the separation efficiency of interfacial charge carrier is a major challenge in photocatalysis. Herein, a new class of C60 -mediated NH2 -MIL-125(Ti)/Zn0.5 Cd0.5 S S-scheme heterojunction with enhanced interfacial charge carrier separation is designed and synthesized. The constructed S-scheme heterojunction thermodynamically favors photocatalytic H2 evolution because of the large driving force resulting from its strong redox abilities. As a consequence, the optimum proportion of C60 -mediated NH2 -MIL-125(Ti)/Zn0.5 Cd0.5 S S-scheme heterojunction displays comparable H2 evolution activity with a rate of 7825.20 µmol h-1 g-1 under visible light irradiation, which is about 93.05 times, 6.38 times and 2.65 times higher than that of 2% C60 /NH2 -MIL-125(Ti), Zn0.5 Cd0.5 S and 45% NH2 -MIL-125(Ti)/Zn0.5 Cd0.5 S, and outperforms the majority of the previously reported MOFs-based photocatalysts. Spectroscopic characterizations and theory calculations indicate that the S-scheme heterojunction can powerfully promote the separation of photogenerated carriers. This work offers a new insight for future design and development of highly active MOFs-based photocatalysts.

12.
Acta Oncol ; 60(2): 252-259, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33063569

RESUMEN

PURPOSE: To evaluate the LETd-weighted biological dose to OARs in proton therapy for breast cancer and to study the relationship of the LETd-weighted biological dose relative to the standard dose (RBE = 1.1) and thereby to provide estimations of the biological dose uncertainties with the standard dose calculations (RBE = 1.1) commonly used in clinical practice. METHOD: This study included 20 patients who received IMPT treatment to the whole breast/chest wall and regional lymph nodes. The LETd distributions were calculated along with the physical dose using an open-source Monte Carlo simulation package, MCsquare. Using the McMahon linear model, the LETd-weighted biological dose was computed from the physical dose and LETd. OAR doses were compared between the Dose (RBE = 1.1) and the LETd-weighted biological dose, on brachial plexus, rib, heart, esophagus, and Ipsilateral lung. RESULTS: On average, the LETd-weighted biological dose compared to the Dose (RBE = 1.1) was higher by 8% for the brachial plexus D0.1 cc, 13% for the ribs D0.5 cc, 24% for mean heart dose, and 10% for the esophagus D0.1 cc, respectively. The LETd-weighted doses to the Ipsilateral lung V5, V10, and V20 were comparable to the Dose (RBE = 1.1). No statistically significant difference in biological dose enhancement to OARs was observed between the intact breast group and the CW group, with the exception of the ribs: the CW group experienced slightly greater biological dose enhancement (13% vs. 12%, p = 0.04) to the ribs than the intact breast group. CONCLUSION: Enhanced biological dose was observed compared to standard dose with assumed RBE of 1.1 for the heart, ribs, esophagus, and brachial plexus in breast/CW and regional nodal IMPT plans. Variable RBE models should be considered in the evaluation of the IMPT breast plans, especially for OARs located near the end of range of a proton beam. Clinical outcome studies are needed to validate model predictions for clinical toxicities.


Asunto(s)
Terapia de Protones , Radioterapia de Intensidad Modulada , Humanos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Efectividad Biológica Relativa
13.
Appl Opt ; 60(31): 10002-10008, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34807195

RESUMEN

Large-scale optical fiber phased arrays (OFPAs) are capable of realizing high-power lasers and high-speed beam steering, which are widely used in long-distance detection and communication. However, dephasing occurring from optical fiber jitter and power amplifier noise can reduce beam quality and steering precision in applications. We demonstrate a two-dimensional 64-element OFPA system that employs a stochastic parallel gradient descent algorithm to synchronize the phases and thus achieve high-quality multi-beam output. Using multi-beam steering, the total scan time for covering a certain field of view can be shorter compared to single-beam steering. Moreover, an avalanche photodiode array is used to enhance the precision of the voltage for beam steering. Experimental results show that the peak sidelobe ratio of the main beam achieves 23.7 dB, and the speed of the beam steering between two discretionary angles is 128 kHz.

14.
Comput Inform Nurs ; 39(2): 97-104, 2020 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-32694483

RESUMEN

Internet-based home care has emerged as a way to relieve the burden of hospitals and meet patients' need for home care. This study aims to explore nurses' attitudes toward Internet-based home care. A cross-sectional online survey was conducted in Ningbo City in China. A self-designed Internet-based home care attitudes questionnaire for nurses (23 items) was used. There were 2039 nurses from 13 hospitals who participated in this online survey. Results reveal that, 1369 nurses (67.1%) were willing to provide Internet-based home care. However, there were significant differences in the attitudes of nurses with different ages (H = 11.86, P = .001), years of work experience (H = 24.257, P = .000), positions (H = 8.850, P = .031), and types of phones (H = 13.096, P = .001). More than 80% of nurses were willing to provide hypodermic and intramuscular injection. But there was a significant difference in the attitudes toward hypodermic injection, intramuscular injection, and pressure ulcer care in nurses with different ages (H = 13.039, P = .005; H = 9.178, P = .027; H = 10.997, P = .012) and a significant difference in the attitudes toward pressure ulcer care in nurses with different years of work experience (H = 15.259, P = .002). Results also indicated that most nurses were worried about their own safety and personal rights protection during Internet-based home care.


Asunto(s)
Actitud del Personal de Salud , Servicios de Atención de Salud a Domicilio/estadística & datos numéricos , Enfermeras y Enfermeros/psicología , Telemedicina , Adulto , Factores de Edad , China , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
15.
J Asian Nat Prod Res ; 21(2): 109-116, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29188722

RESUMEN

Three new sesquiterpenes, methyl 4-isopropyl-7-methoxy-6-methylnaphthalene-1-carboxylate (1), methyl 2-hydroxy-4-isopropyl-7-methoxy-6-methylnaphthalene-1-carboxylate (2), and methyl 2-hydroxy-6-(hydroxymethyl)-4-isopropyl-7-methoxynaphthalene-1-carboxylate (3), together with three known sesquiterpenes (4-6), were isolated from the stems of Nicotiana tabacum. Their structures were determined by means of HRESIMS and extensive 1D and 2D NMR spectroscopic studies. The results showed that compounds 2, 3, and 5 exhibited high anti-TMV activity with inhibition rates of 33.6, 35.8, and 36.7%. Compounds 1-6 showed weak inhibitory activities against some tested human tumor cell lines (NB4, A549, SHSY5Y, PC3, and MCF7) with IC50 values in the range of 6.7-9.6 µM.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Nicotiana/química , Sesquiterpenos/farmacología , Antineoplásicos Fitogénicos/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Espectroscopía de Resonancia Magnética , Estructura Molecular , Sesquiterpenos/química
16.
J Med Syst ; 43(7): 194, 2019 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-31114956

RESUMEN

3D/3D image registration in IGRT, which aligns planning Computed Tomography (CT) image set with on board Cone Beam CT (CBCT) image set in a short time with high accuracy, is still a challenge due to its high computational cost and complex anatomical structure of medical image. In order to overcome these difficulties, a new method is proposed which contains a coarse registration and a fine registration. For the coarse registration, a supervised regression convolutional neural networks (CNNs) is used to optimize the spatial variation by minimizing the loss when combine the CT images with the CBCT images. For the fine registration, intensity-based image registration is used to calculate the accurate spatial difference of the input image pairs. A coarse registration can get a rough result with a wide capture range in less than 0.5 s. Sequentially a fine registration can get accurate results in a reasonable short time. RSD-111 T chest phantom was used to test our new method. The set-up error was calculated in less than 10s in time scale, and was reduced to sub-millimeter level in spatial scale. The average residual errors in translation and rotation are within ±0.5 mm and ± 0.2°.


Asunto(s)
Planificación de la Radioterapia Asistida por Computador , Errores de Configuración en Radioterapia/prevención & control , Radioterapia Guiada por Imagen/métodos , Algoritmos , Humanos , Imagenología Tridimensional , Fantasmas de Imagen , Tomografía Computarizada por Rayos X
17.
Opt Express ; 26(8): 10048-10064, 2018 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-29715947

RESUMEN

To obtain a high imaging frame rate, a computational ghost imaging system scheme is proposed based on optical fiber phased array (OFPA). Through high-speed electro-optic modulators, the randomly modulated OFPA can provide much faster speckle projection, which can be precomputed according to the geometry of the fiber array and the known phases for modulation. Receiving the signal light with a low-pixel APD array can effectively decrease the requirement on sampling quantity and computation complexity owing to the reduced data dimensionality while avoiding the image aliasing due to the spatial periodicity of the speckles. The results of analysis and simulation show that the frame rate of the proposed imaging system can be significantly improved compared with traditional systems.

18.
J Sport Rehabil ; 27(6): 605-608, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29651908

RESUMEN

OBJECTIVES: The efficacy of eccentric cycling has been proved in research, clinical, and sport training activities. However, several constraints make it difficult to use commercially available eccentric cycle ergometers. This study will stimulate the application of eccentric cycling as an exercise modality. STUDY DESIGN: University research laboratory. METHODS: In this study, the multiple-input single-output (MISO) Wiener nonlinear model was applied to the design of the eccentric training system. Particle Swarm Optimization (PSO) algorithm was then applied to identify the parameters of the MISO Wiener nonlinear model. The computer software embedded with MISO model was programmed for not only controlling and monitoring the running status of the eccentric training system, but also collecting data in a flexible and convenient manner. RESULTS: The correlation coefficient of 0.9985 and root mean square error of 3.3264 between the collected power value and the estimated power value from the model shows the good performance of the model. CONCLUSION: The proposed method for the design of the eccentric training system using MISO Wiener nonlinear model provides a new way for eccentric research and training.


Asunto(s)
Algoritmos , Ciclismo , Ergometría/métodos , Prueba de Esfuerzo , Dinámicas no Lineales , Diseño de Equipo , Humanos , Programas Informáticos
19.
Zhongguo Zhong Yao Za Zhi ; 43(20): 4074-4076, 2018 Oct.
Artículo en Zh | MEDLINE | ID: mdl-30486533

RESUMEN

A new isobenzofuranone derivative has been isolated from Phlomis betonicoides by using various chromatographic techniques, including silica gel, Sephadex LH-20, MCI-gel resin and RP-HPLC. This compound was determined as 5-(3-hydroxypropyl)-2,2-dimethyl-2H-furo[3,4-h]chromen-7(9H)-one (1) by NMR, MS, IR and UV spectroscopic data. Compound 1 showed potent antibacterial activity with an MIC90 value of (58.4 ± 4.2) mg·L⁻¹ for methicillin resistant Staphylococcus aureus (MRSA) strain [levofloxacin as a control with MIC90 value of (52.8±4.6) mg·L⁻¹].


Asunto(s)
Antibacterianos/farmacología , Benzofuranos/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Phlomis/química , Antibacterianos/aislamiento & purificación , Benzofuranos/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología
20.
J Asian Nat Prod Res ; 19(8): 766-773, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27967214

RESUMEN

Three new benzolactones (1-3), together with four known ones (4-7), were isolated from the whole herb of Lavandula angustifolia. Their structures were established on the basis of detailed spectroscopic analysis (1D- and 2D-NMR, HRESIMS, UV, and IR) and comparison with data reported in the literature. New compounds were evaluated for their anti-tobacco mosaic virus (TMV) activities and cytotoxic activities. The results revealed that compounds 1-3 showed obvious anti-TMV activities with inhibition rates of 26.9, 30.2, and 28.4%, which were at the same grade as positive control. Compounds 1-3 also showed weak inhibitory activities against some tested human tumor cell lines with IC50 values in the range of 32.1-7.6 µM.


Asunto(s)
Antivirales/aislamiento & purificación , Antivirales/farmacología , Benzofuranos/aislamiento & purificación , Benzofuranos/farmacología , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/farmacología , Furocumarinas/aislamiento & purificación , Furocumarinas/farmacología , Lactonas/aislamiento & purificación , Lactonas/farmacología , Lavandula/química , Antivirales/química , Benzofuranos/química , Ensayos de Selección de Medicamentos Antitumorales , Medicamentos Herbarios Chinos/química , Furocumarinas/química , Humanos , Concentración 50 Inhibidora , Lactonas/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Hojas de la Planta/química , Virus del Mosaico del Tabaco/efectos de los fármacos
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