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1.
Opt Lett ; 49(9): 2321-2324, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691709

RESUMO

In this Letter, we propose a crackless high-aspect-ratio processing method based on a temporally shaped ultrafast laser. The laser pulse is temporally split into two sub pulses: one with smaller energy is used to excite electrons but without ablation so that the applied pressure to the sample is weak, and the other one is used to heat the electrons and achieve material removal after it is temporally stretched by a chirped volume Bragg grating (CVBG). Compared with the conventional ultrafast laser processing, the crack generation is almost suppressed by using this proposed method. The hole depth increases more than 3.3 times, and the aspect ratio is improved at least 2.2 times. Moreover, processing dynamics and parameter dependence are further experimentally studied. It shows that the processing highly depends on the density of electrons excited by the first pulse (P1) and the energy of the second pulse (P2). This novel, to the best of our knowledge, method provides a new route for the precise processing of wide-bandgap materials.

2.
PLoS One ; 19(5): e0304381, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38809928

RESUMO

Cancer education programs are regularly conducted in schools in Japan. Previous reports on their effectiveness were based on surveys conducted several months after the education. We aimed to evaluate whether cancer education for children influenced their behavioral changes in adulthood. We targeted schools where the Japan Cancer Society has conducted the programs since 2011 and the program participants are older than 21 years currently. Invitations were sent to the participants and controls who graduated one year before or after the participants, and answers were obtained using an online questionnaire. Data were collected on the willingness to undergo cancer screening, sociodemographic characteristics, healthy behaviors, and health literacy. We compared the data from the program participants with those from controls. We requested cooperation from 13 schools; however, only one agreed. The common reason for refusal was privacy concerns. In the all-boys participating school in Tokyo, there was no significant difference in background information between the cancer education (38 participants) and control (55 participants) groups. Multiple linear regression showed that healthcare or welfare education background (ß = 0.25, p = 0.01) and health literacy (ß = 0.24, p = 0.02) were significant predictors of cancer screening intention, while the presence of cancer education (p = 0.25) was not. Despite severe selection bias, this is the first study to examine the long-term impacts of cancer education. We found no significant impacts on the measured outcome. However, the educational content at that time differed from that of today, and the program's efficacy should not be negated.


Assuntos
Educação em Saúde , Letramento em Saúde , Neoplasias , Humanos , Masculino , Projetos Piloto , Adulto , Neoplasias/prevenção & controle , Inquéritos e Questionários , Japão , Instituições Acadêmicas , Feminino , Adulto Jovem , Detecção Precoce de Câncer/psicologia , Detecção Precoce de Câncer/estatística & dados numéricos , Comportamentos Relacionados com a Saúde
3.
J Cancer Educ ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809493

RESUMO

Health literacy (HL) plays a vital role in an individual's ability to make informed health decisions. Japan faces several challenges in cervical cancer control, including low human papillomavirus (HPV) vaccination and screening rates, underutilization of radiotherapy, and limited HL. This study explored the association between HL and knowledge of cervical cancer and radiotherapy, particularly among young Japanese women. We conducted a web-based survey among users of LunaLuna, a popular women's healthcare application, to assess their HL and knowledge about cervical cancer and radiotherapy through a 46-question survey. We compared three groups in terms of HL (inadequate, problematic, and sufficient & excellent). Multiple regression analysis was used to identify factors associated with knowledge. In total, 1468 respondents were included in this study. HL was positively correlated with knowledge scores (inadequate: 51.8%; problematic: 56.3%; sufficient & excellent: 60%). Participants displayed relatively low accuracy for treatment-related questions. Higher HL (ß = 0.15, p < 0.01), education (ß = - 0.11, p < 0.01), cervical cancer screening (ß = - 0.11, p < 0.01), income (ß = 0.09, p < 0.01), and employment (ß = - 0.06, p = 0.04) were significant factors affecting knowledge of cervical cancer and radiotherapy. Our findings underscore the pivotal role of HL in promoting cervical cancer prevention and providing a better understanding of radiotherapy. Despite factors such as age, education, and history of cervical cancer screening, HL showed the strongest association with knowledge of cervical cancer and radiotherapy. The enhancement of HL and knowledge dissemination may be critical for promoting cervical cancer prevention and radiotherapy in Japan.

4.
Radiol Phys Technol ; 17(2): 458-466, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38700638

RESUMO

The purpose of the study is to investigate the variation in Hounsfield unit (HU) values calculated using dual-energy computed tomography (DECT) scanners. A tissue characterization phantom inserting 16 reference materials were scanned three times using DECT scanners [dual-layer CT (DLCT), dual-source CT (DSCT), and fast kilovoltage switching CT (FKSCT)] changing scanning conditions. The single-energy CT images (120 or 140 kVp), and virtual monochromatic images at 70 keV (VMI70) and 140 keV (VMI140) were reconstructed, and the HU values of each reference material were measured. The difference in HU values was larger when the phantom was scanned using the half dose with wrapping with rubber (strong beam-hardening effect) compared with the full dose without the rubber (reference condition), and the difference was larger as the electron density increased. For SECT, the difference in HU values against the reference condition measured by the DSCT (3.2 ± 5.0 HU) was significantly smaller (p < 0.05) than that using DLCT with 120 kVp (22.4 ± 23.8 HU), DLCT with 140 kVp (11.4 ± 12.8 HU), and FKSCT (13.4 ± 14.3 HU). The respective difference in HU values in the VMI70 and VMI140 measured using the DSCT (10.8 ± 17.1 and 3.5 ± 4.1 HU) and FKSCT (11.5 ± 21.8 and 5.5 ± 10.4 HU) were significantly smaller than those measured using the DLCT120 (23.1 ± 27.5 and 12.4 ± 9.4 HU) and DLCT140 (22.3 ± 28.6 and 13.1 ± 11.4 HU). The HU values and the susceptibility to beam-hardening effects varied widely depending on the DECT scanners.


Assuntos
Imagens de Fantasmas , Tomografia Computadorizada por Raios X , Tomografia Computadorizada por Raios X/métodos , Processamento de Imagem Assistida por Computador/métodos , Doses de Radiação
5.
Support Care Cancer ; 32(6): 391, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38806815

RESUMO

PURPOSE: This study focused on identifying the factors influencing the decision-making process in patients with localized prostate and cervical cancer in Japan and specifically examining the choice between surgery and radiotherapy. METHODS: Patients with specific cancer stages registered with a healthcare research company for whom radical surgery or radiotherapy was equally effective and recommended participated in this cross-sectional online survey. RESULTS: The responses of 206 and 231 patients with prostate and cervical cancer, respectively, revealed that both groups relied heavily on the physicians' recommendations (prostate: odds ratio (OR) = 40.3, p < 0.001; cervical: OR = 5.59, p < 0.001) and their impression of radiotherapy (prostate: OR = 9.22, p < 0.001; cervical: OR = 2.31, p < 0.001). Factors such as hypertension (OR = 6.48, p < 0.05), diabetes mellitus (OR = 9.68, p < 0.05), employment status (OR = 0.08, p < 0.01), and impressions of surgery (OR = 0.14, p < 0.01) also played a significant role in patients with prostate cancer. In contrast, the specialty of the physician (OR = 4.55, p < 0.05) proposing the treatment influenced the decision-making process of patients with cervical cancer. Information sources varied between the two groups: patients with prostate cancer were more inclined towards printed materials, whereas patients with cervical cancer were more inclined towards interpersonal relationships. CONCLUSION: Although several limitations, such as the sample and recall bias, were noted, this study emphasizes the role of psychosocial factors in the decision-making process and the requirement for tailored information sources.


Assuntos
Tomada de Decisões , Neoplasias da Próstata , Neoplasias do Colo do Útero , Humanos , Masculino , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia , Estudos Transversais , Pessoa de Meia-Idade , Feminino , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/cirurgia , Idoso , Japão , Adulto , Inquéritos e Questionários
6.
Int J Hyperthermia ; 41(1): 2335199, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38565204

RESUMO

PURPOSE: c-Jun N-terminal kinases (JNKs) comprise a subfamily of mitogen-activated protein kinases (MAPKs). The JNK group is known to be activated by a variety of stimuli. However, the molecular mechanism underlying heat-induced JNK activation is largely unknown. The aim of this study was to clarify how JNK activity is stimulated by heat. METHODS AND MATERIALS: The expression levels of various MAPK members in HeLa cells, with or without hyperthermia treatment, were evaluated via western blotting. The kinase activity of MAPK members was assessed through in vitro kinase assays. Cell death was assessed in the absence or presence of siRNAs targeting MAPK-related members. RESULTS: Hyperthermia decreased the levels of MAP3Ks, such as ASK1 and MLK3 which are JNK kinase kinase members, but not those of the downstream MAP2K/SEK1 and MAPK/JNK. Despite the reduced or transient phosphorylation of ASK1, MLK3, or SEK1, downstream JNK was phosphorylated in a temperature-dependent manner. In vitro kinase assays demonstrated that heat did not directly stimulate SEK1 or JNK. However, the expression levels of DUSP16, a JNK phosphatase, were decreased upon hyperthermia treatment. DUSP16 knockdown enhanced the heat-induced activation of ASK1-SEK1-JNK pathway and apoptosis. CONCLUSION: JNK was activated in a temperature-dependent manner despite reduced or transient phosphorylation of the upstream MAP3K and MAP2K. Hyperthermia-induced degradation of DUSP16 may induce activation of the ASK1-SEK1-JNK pathway and subsequent apoptosis.


Assuntos
Hipertermia Induzida , Sistema de Sinalização das MAP Quinases , Humanos , Células HeLa , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Apoptose/fisiologia
7.
Clin Exp Rheumatol ; 42(3): 658-665, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38436267

RESUMO

OBJECTIVES: Several therapeutic agents have been developed and used for the clinical treatment of systemic lupus erythematosus (SLE). In cases where SLE is accompanied by severe organ failures, such as neuropsychiatric lupus erythematosus (NPSLE) and acute onset of lupus nephritis, the use of potent immunosuppressive drugs, such as cyclophosphamide, is necessary. However, potent immunosuppressive drugs are known to increase infection risks. Thus, the development of therapeutic agents with novel mechanisms is urgently required. Previously, we reported that treatment with lysophosphatidic acid (LPA) prevents depression-like behaviours by suppressing microglial activation in MRL/lpr mice. In this study, we examined whether the treatment with LPA improves glomerulonephritis by affecting systemic immunity in MRL/lpr mice. METHODS: Eighteen-week-old MRL/lpr mice were treated with a vehicle or LPA for 3 weeks. After treatment, the glomerular inflammation and damage parameters were compared between the 2 groups. Moreover, we examined the effects of LPA on immune cells by flow cytometry using isolated splenocytes. RESULTS: LPA treatment in MRL/lpr mice significantly reduced the daily urinary albumin content and suppressed the CD68-positive cells and Periodic acid-Schiff (PAS)-positive areas in the glomeruli. The treatment also suppressed plasma anti-dsDNA antibodies and inflammatory cytokines in MRL/lpr mice. Although LPA did not significantly affect the total number of splenocytes, the treatment significantly reduced CD11b+Ly6G-Ly6C- cells (mature macrophages), as well as CD11b+Ly6G-Ly6C-CD68+ cells (activated mature macrophages). CONCLUSIONS: These results suggest that LPA may improve glomerulonephritis by suppressing macrophage activation in MRL/lpr mice.


Assuntos
Glomerulonefrite , Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Lisofosfolipídeos , Animais , Camundongos , Modelos Animais de Doenças , Ativação de Macrófagos , Camundongos Endogâmicos MRL lpr , Nefrite Lúpica/tratamento farmacológico , Nefrite Lúpica/prevenção & controle , Glomerulonefrite/tratamento farmacológico , Glomerulonefrite/prevenção & controle , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico
8.
Nutrition ; 122: 112372, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38428218

RESUMO

OBJECTIVES: Aging and excessive fat intake may additively induce dysbiosis of the gut microbiota and intestinal inflammatory damage. Here, we analyzed microbiota dysbiosis and intestinal injury in high-fat diet-loaded senescence-accelerated mice (SAMP8). Additionally, we examined whether treatment with molecular hydrogen could improve the intestinal environment. METHODS: SAMP8 and SAMR1 (control) mice were first fed a normal diet (ND) or high-fat diet (HFD) for 10 wk (n = 10 each group). Subsequently, HFD was supplemented with a placebo jelly or hydrogen-rich jelly (HRJ) for 4 wk. After treatment, isolated small intestinal tissues were used for hematoxylin and eosin staining, immunofluorescence staining, and thiobarbituric acid reactive substances (TBARS) assay. Furthermore, we analyzed alterations in the microbiota composition in cecal feces using 16S rRNA gene analysis for microbiota profiling. Statistical analyses were performed using unpaired Student's t tests or one-way analysis of variance and Tukey's post hoc test for multiple comparisons. RESULT: HFD feeding reduced the expression of caudal-related homeobox transcription factor 2 (CDX2) and 5-bromo-2'-deoxyuridine (BrdU) and enhanced malondialdehyde (MDA) levels in the small intestine of SAMP8. HRJ treatment improved the reduction in CDX2 and BrdU and enhanced MDA levels. We performed a sequence analysis of the gut microbiota at the genus level and identified 283 different bacterial genera from the 30 samples analyzed in the study. Among them, Parvibacter positively correlated with both HFD intake and aging, whereas 10 bacteria, including Anaerofustis, Anaerosporobacter, Butyricicoccus, and Ruminococcus were negatively correlated with both HFD and aging. HRJ treatment increased Lactinobactor and decreased Akkermansia, Gracilibacter, and Marvinbryantia abundance. CONCLUSION: Our findings suggest that treatment with molecular hydrogen may affect microbiota profiling and suppress intestinal injury in HFD-loaded SAMP8.


Assuntos
Dieta Hiperlipídica , Enteropatias , Camundongos , Animais , Dieta Hiperlipídica/efeitos adversos , Disbiose/microbiologia , RNA Ribossômico 16S/genética , Bromodesoxiuridina/uso terapêutico , Intestino Delgado/metabolismo , Enteropatias/tratamento farmacológico , Enteropatias/etiologia , Camundongos Endogâmicos C57BL
9.
Radiol Phys Technol ; 17(2): 389-395, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38466497

RESUMO

To investigate the geometric accuracy of the radiation focal point (RFP) and cone-beam computed tomography (CBCT) over long-term periods for the ICON Leksell Gamma Knife radiosurgery system. This phantom study utilized the ICON quality assurance tool plus, and the phantom was manually set on the patient position system before the implementation of treatment for patients. The deviation of the RFP position from the unit center point (UCP) and the positions of the four ball bearings (BBs) in the CBCT from the reference position were automatically analyzed. During 544 days, a total of 269 analyses were performed on different days. The mean ± standard deviation (SD) of the deviation between measured RFP and UCP was 0.01 ± 0.03, 0.01 ± 0.03, and -0.01 ± 0.01 mm in the X, Y, and Z directions, respectively. The deviations with offset values after the cobalt-60 source replacement (0.00 ± 0.03, -0.01 ± 0.01, and -0.01 ± 0.01 mm in the X, Y, and Z directions, respectively) were significantly (p = 0.001) smaller than those before the replacement (0.02 ± 0.03, 0.02 ± 0.01, and -0.02 ± 0.01 mm in the X, Y, and Z directions, respectively). The overall mean ± SD of four BBs was -0.03 ± 0.03, -0.01 ± 0.05, and 0.01 ± 0.03 mm in the X, Y, and Z directions, respectively. Geometric positional accuracy was ensured to be within 0.1 mm on most days over a long-term period of more than 500 days.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Imagens de Fantasmas , Radiocirurgia , Radiocirurgia/instrumentação , Garantia da Qualidade dos Cuidados de Saúde , Humanos , Controle de Qualidade , Fatores de Tempo
10.
Med Phys ; 51(4): 2378-2385, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38421685

RESUMO

BACKGROUND: The breath-hold radiotherapy has been increasingly used to mitigate interfractional and intrafractional breathing impact on treatment planning and beam delivery. Previous techniques include body surface measurements or radiopaque metal markers, each having known disadvantages. PURPOSE: We recently proposed a new markerless technique without the disadvantages, where diaphragm was registered between DRR and fluoroscopic x-ray projection images every 180 ms during VMAT delivery. An initial validation of the proposed diaphragm tracking system (DiaTrak) was performed using a chest phantom to evaluate its characteristics. METHODS: Diaphragm registration was performed between DRR and projection streaming kV x-ray images of a chest phantom during VMAT delivery. Streaming data including the projection images and the beam angles were transferred from a linac system to an external PC, where the diaphragm registration accuracy and beam-off latency were measured based on image cross correlation between the DRR and the projection images every 180 ms. RESULTS: It was shown that the average of the beam-off latency was 249.5 ms and the average of the diaphragm registration error was 0.84 mm CONCLUSIONS: Initial validation of the proposed DiaTrak system for multiple breath-hold VMAT of abdominal tumors has been successfully completed with a chest phantom. The resulting beam-off latency and the diaphragm registration error were regarded clinically acceptable.


Assuntos
Neoplasias Abdominais , Neoplasias Pulmonares , Radioterapia de Intensidade Modulada , Humanos , Diafragma/diagnóstico por imagem , Radioterapia de Intensidade Modulada/métodos , Neoplasias Pulmonares/radioterapia , Neoplasias Abdominais/diagnóstico por imagem , Neoplasias Abdominais/radioterapia , Suspensão da Respiração , Imagens de Fantasmas , Planejamento da Radioterapia Assistida por Computador/métodos
11.
J Appl Clin Med Phys ; 25(6): e14294, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38319652

RESUMO

PURPOSE: To explore the potential of quantitative parameters of the hydrogel spacer distribution as predictors for separating the rectum from the planning target volume (PTV) in linear-accelerator-based stereotactic body radiotherapy (SBRT) for prostate cancer. METHODS: Fifty-five patients underwent insertion of a hydrogel spacer and were divided into groups 1 and 2 of the PTV separated from and overlapping with the rectum, respectively. Prescribed doses of 36.25-45 Gy in five fractions were delivered to the PTV. The spacer cover ratio (SCR) and hydrogel-implant quality score (HIQS) were calculated. RESULTS: Dosimetric and quantitative parameters of the hydrogel spacer distribution were compared between the two groups. For PTV, D99% in group 1 (n = 29) was significantly higher than that in group 2 (n = 26), and Dmax, D0.03cc, D1cc, and D10% for the rectum were significantly lower in group 1 than in group 2. The SCR for prostate (89.5 ± 12.2%) in group 1 was significantly higher (p < 0.05) than that in group 2 (74.7 ± 10.3%). In contrast, the HIQS values did not show a significant difference between the groups. An area under the curve of 0.822 (95% confidence interval, 0.708-0.936) for the SCR was obtained with a cutoff of 93.6%, sensitivity of 62.1%, and specificity of 100%. CONCLUSIONS: The SCR seems promising to predict the separation of the rectum from the PTV in linear-accelerator-based SBRT for prostate cancer.


Assuntos
Órgãos em Risco , Neoplasias da Próstata , Radiocirurgia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Humanos , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia , Masculino , Radiocirurgia/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Órgãos em Risco/efeitos da radiação , Idoso , Aceleradores de Partículas/instrumentação , Hidrogéis/química , Pessoa de Meia-Idade , Prognóstico , Radiometria/métodos , Idoso de 80 Anos ou mais
12.
Strahlenther Onkol ; 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38180494

RESUMO

BACKGROUND: Although robot-assisted radical prostatectomy (RARP) and intensity-modulated radiotherapy are the leading respective techniques of prostatectomy and radiotherapy for localized prostate cancer, almost no study has directly compared their outcomes; none have compared mortality outcomes. METHODS: We compared 6­year outcomes of RARP (n = 500) and volumetric modulated arc therapy (VMAT, a rotational intensity-modulated radiotherapy, n = 360) in patients with cT1-4N0M0 prostate cancer. We assessed oncological outcomes, namely overall survival (OS), cancer-specific survival (CSS), radiological recurrence-free survival (rRFS), and biochemical recurrence-free survival (bRFS), using propensity score matching (PSM). We also assessed treatment-related complication outcomes of prostatectomy and radiotherapy. RESULTS: The median follow-up duration was 79 months (> 6 years). PSM generated a matched cohort of 260 patients (130 per treatment group). In the matched cohort, RARP and VMAT showed equivalent results for OS, CSS, and rRFS: both achieved excellent 6­year outcomes for OS (> 96%), CSS (> 98%), and rRFS (> 91%). VMAT had significantly longer bRFS than RARP, albeit based on different definitions of biochemical recurrence. Regarding complication outcomes, patients who underwent RARP had minimal (2.6%) severe perioperative complications and achieved excellent continence recovery (91.6 and 68.8% of the patients achieved ≤ 1 pad/day and pad-free, respectively). Patients who underwent VMAT had an acceptable rate (20.0%) of grade ≥ 2 genitourinary complications and a very low rate (4.4%) of grade ≥ 2 gastrointestinal complications. CONCLUSION: On the basis of PSM after a 6-year follow-up, RARP and VMAT showed equivalent and excellent oncological outcomes, as well as acceptable complication profiles.

13.
Phys Med ; 117: 103182, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38086310

RESUMO

PURPOSE: To investigate the prognostic power of cone-beam computed-tomography (CBCT)-based delta-radiomics in esophageal squamous cell cancer (ESCC) patients treated with concurrent chemoradiotherapy (CCRT). METHODS: We collected data from 26 ESCC patients treated with CCRT. CBCT images acquired at five time points (1st-5th week) per patient during CCRT were used in this study. Radiomic features were extracted from the five CBCT images on the gross tumor volumes. Then, 17 delta-radiomic feature sets derived from five types of calculations were obtained for all the cases. Leave-one-out cross-validation was applied to investigate the prognostic power of CBCT-based delta-radiomic features. Feature selection and construction of a prediction model using Coxnet were performed using training samples. Then, the test sample was classified into high or low risk in each cross-validation fold. Survival analysis for the two groups were performed to evaluate the prognostic power of the extracted CBCT-based delta-radiomic features. RESULTS: Four delta-radiomic feature sets indicated significant differences between the high- and low-risk groups (p < 0.05). The highest C-index in the 17 delta-radiomic feature sets was 0.821 (95 % confidence interval, 0.735-0.907). That feature set had p-value of the log-rank test and hazard ratio of 0.003 and 4.940 (95 % confidence interval, 1.391-17.544), respectively. CONCLUSIONS: We investigated the potential of using CBCT-based delta-radiomics for prognosis of ESCC patients treated with CCRT. It was demonstrated that delta-radiomic feature sets based on the absolute value of relative difference obtained from the early to the middle treatment stages have high prognostic power for ESCC.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Humanos , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/terapia , Prognóstico , Radiômica , Estudos Retrospectivos , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/terapia , Tomografia Computadorizada de Feixe Cônico/métodos , Quimiorradioterapia , Células Epiteliais/patologia
14.
Cureus ; 15(11): e48188, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38054156

RESUMO

In liver stereotactic body radiotherapy (SBRT), precise image guidance is paramount, serving as the foundation of this treatment approach. The accuracy of SBRT in liver cancer treatment heavily relies on meticulous imaging techniques. The diaphragm, situated adjacent to the liver, is a crucial anatomical structure susceptible to positional and motion variations, which can potentially impact the accuracy of liver tumor targeting. This study explores the application of real-time kilovoltage projection streaming images (KVPSI) in comparison to digitally reconstructed radiography (DRR) for assessing diaphragm position deviations during breath-hold liver tumor SBRT. A 76-year-old male diagnosed with cholangiocarcinoma underwent breath-hold SBRT using split arc volumetric modulated arc therapy (VMAT), where a full arc was split into six sub-arcs, each spanning 60 degrees. The diaphragm dome positions were continuously monitored through KVPSI during treatment. The intrafractional position deviations of the diaphragm were calculated and analyzed for each split arc. The case report revealed a mean diaphragm dome deviation of 0.47 mm (standard deviation: 4.47 mm) in the entire arc. This pioneering study showcases the feasibility of intrafractional diaphragm position variation assessment using real-time KVPSI during the breath-hold liver tumor VMAT-SBRT. Integrating real-time imaging techniques enhances our comprehension of the intra-breath-hold variations, thereby guiding adaptive treatment strategies and potentially improving treatment outcomes. Clinical validation through further research is essential.

15.
Sci Adv ; 9(51): eadj8608, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38117881

RESUMO

Single-shot optical imaging based on ultrashort lasers has revealed nonrepetitive processes in subnanosecond timescales beyond the recording range of conventional high-speed cameras. However, nanosecond photography without sacrificing short exposure time and image quality is still missing because of the gap in recordable timescales between ultrafast optical imaging and high-speed electronic cameras. Here, we demonstrate nanosecond photography and ultrawide time-range high-speed photography using a spectrum circuit that produces interval-tunable pulse trains while keeping short pulse durations. We capture a shock wave propagating through a biological cell with a 1.5-ns frame interval and 44-ps exposure time while suppressing image blur. Furthermore, we observe femtosecond laser processing over multiple timescales (25-ps, 2.0-ns, and 1-ms frame intervals), showing that the plasma generated at the picosecond timescale affects subsequent shock wave formation at the nanosecond timescale. Our technique contributes to accumulating data of various fast processes for analysis and to analyzing multi-timescale phenomena as a series of physical processes.

16.
ACS Macro Lett ; 12(10): 1389-1395, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37782005

RESUMO

Stimulus-responsive polymer materials are an attractive alternative to conventional supramolecular and polymer assemblies for applications in sensing, imaging, and drug-delivery systems. Herein, we synthesized a series of pyrene-labeled α- and ε-poly-l-lysine conjugates with varying degrees of substitution (DSs). Hydrostatic-pressure-UV/vis, fluorescence, and excitation spectroscopies and fluorescence lifetime measurements revealed ground-state conformers and excited-state ensembles emitting fluorescence with variable intensities. The polylysine-based chemosensors demonstrated diverse ratiometric responses to hydrostatic pressure through adjustments in polar solvents, DSs, and polymer backbones. Additionally, the fluorescence chemosensor exhibited a promising glum value of 3.2 × 10-3, indicating potential applications in chiral fluorescent materials. This study offers valuable insights into the development of smart hydrostatic-pressure-responsive polymer materials.

17.
J Radiat Res ; 64(6): 940-947, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37839063

RESUMO

To explore predictors of the histopathological response to preoperative chemoradiotherapy (CRT) in patients with pancreatic cancer (PC) using dual-energy computed tomography-reconstructed images. This retrospective study divided 40 patients who had undergone preoperative CRT (50-60 Gy in 25 fractions) followed by surgical resection into two groups: the response group (Grades II, III and IV, evaluated from surgical specimens) and the nonresponse group (Grades Ia and Ib). The computed tomography number [in Hounsfield units (HUs)] and iodine concentration (IC) were measured at the locations of the aorta, PC and pancreatic parenchyma (PP) in the contrast-enhanced 4D dual-energy computed tomography images. Logistic regression analysis was performed to identify predictors of histopathological response. Univariate analysis did not reveal a significant relation between any parameter and patient characteristics or dosimetric parameters of the treatment plan. The HU and IC values in PP and the differences in HU and IC between the PP and PC (ΔHU and ΔIC, respectively) were significant predictors for distinguishing the response (n = 24) and nonresponse (n = 16) groups (P < 0.05). The IC in PP and ΔIC had a higher area under curve values [0.797 (95% confidence interval, 0.659-0.935) and 0.789 (0.650-0.928), respectively] than HU in PP and ΔHU [0.734 (0.580-0.889) and 0.721 (0.562-0.881), respectively]. The IC value could potentially be used for predicting the histopathological response in patients who have undergone preoperative CRT.


Assuntos
Iodo , Neoplasias Pancreáticas , Humanos , Estudos Retrospectivos , Meios de Contraste , Tomografia Computadorizada por Raios X/métodos , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/terapia , Quimiorradioterapia/métodos , Neoplasias Pancreáticas
18.
Phys Med ; 113: 102648, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37672845

RESUMO

PURPOSE: The purpose of this study is to develop a virtual CBCT simulator with a head and neck (HN) human phantom library and to demonstrate the feasibility of elemental material decomposition (EMD) for quantitative CBCT imaging using this virtual simulator. METHODS: The library of 36 HN human phantoms were developed by extending the ICRP 110 adult phantoms based on human age, height, and weight statistics. To create the CBCT database for the library, a virtual CBCT simulator that simulated the direct and scattered X-ray on a flat panel detector using ray-tracing and deep-learning (DL) models was used. Gaussian distributed noise was also included on the flat panel detector, which was evaluated using a real CBCT system. The usefulness of the virtual CBCT system was demonstrated through the application of the developed DL-based EMD model for case involving virtual phantom and real patient. RESULTS: The virtual simulator could generate various virtual CBCT images based on the human phantom library, and the prediction of the EMD could be successfully performed by preparing the CBCT database from the proposed virtual system, even for a real patient. The CBCT image degradation owing to the scattered X-ray and the statistical noise affected the prediction accuracy, although these effects were minimal. Furthermore, the elemental distribution using the real CBCT image was also predictable. CONCLUSIONS: This study demonstrated the potential of using computer vision for medical data preparation and analysis, which could have important implications for improving patient outcomes, especially in adaptive radiation therapy.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Cabeça , Adulto , Humanos , Imagens de Fantasmas , Bases de Dados Factuais , Pescoço
20.
Hum Cell ; 36(6): 2006-2015, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37540445

RESUMO

Systemic lupus erythematosus (SLE) is an autoimmune disease associated with the production of double-stranded DNA (dsDNA) antibodies and other antibodies that predominantly affects women with a wide range of lesions. Although neuropsychiatric lupus erythematosus (NPSLE), characterized by neuropsychiatric symptoms related to cerebrovascular diseases or depression, ranks high in severity, no specific treatment has been defined. Two-carba cyclic phosphatidic acid (2ccPA), a derivative of cyclic phosphatidic acid, was isolated from the true slime mold Physarum polycephalum in 1992. 2ccPA treatment suppresses neuroinflammation and promotes tissue repair in mouse multiple sclerosis and traumatic brain injury models. In this study, we performed behavioral tests on MRL/lpr mice as an NPSLE model. MRL/lpr mice showed increased depression-like behaviors compared with control mice, which were significantly suppressed by 2ccPA treatment. The expression of CD68, an M1 phenotypic marker of microglia, was significantly elevated in the prefrontal cortex and hippocampus of MRL/lpr mice, which was significantly suppressed by 2ccPA treatment. In contrast, the expression of Arginase1, an M2 phenotypic marker of microglia, was significantly increased by 2ccPA treatment. Compared to control mice, MRL/lpr mice showed higher plasma levels of anti-dsDNA antibodies, which are mainly involved in SLE pathogenesis. 2ccPA treatment decreased these levels in the MRL/lpr mice. These results suggest that 2ccPA treatment suppresses behavioral abnormalities by promoting a microglial phenotypic switch from M1 to M2 in MRL/lpr mice.

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