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Commissioning of respiratory‐gated 4D dynamic dose calculations for various gating widths without spot timestamp in proton pencil beam scanning
Background: Proton pencil beam scanning (PBS) is susceptible to dose degradation because of interplay effects on moving targets. For cases of unacceptable motion, respiratory-gated (RG) irradiation is an effective alternative to free breathing (FB) irradiation. However, the introduction of RG irradiation with larger gate widths (GW) is hindered by interplay effects, which are analogous to those observed with FB irradiation. Accurate estimation of interplay effects can be performed by recording spot timestamps. However, our machine lacks this feature, making it imperative to find an alternative approach. Thus, we developed an RG 4-dimensional dynamic dose (RG-4DDD) system without spot timestamps.
Purpose: This study aimed to investigate the accuracy of calculated doses from the RG-4DDD system for PBS plans with varying breathing curves, amplitudes, and periods for 10%–50% GW.
Methods: RG-4DDDs were reconstructed using in-house developed software that assigned timestamps to individual spots, integrated start times for spills with breathing curves, and utilized deformable registrations for dose accumulation. Three cubic verification plans were created using a heterogeneous phantom. Additionally, typical liver and lung cases were employed for patient plan validation. Single- and multi-field-optimized (SFO and IMPT) plans (ten beams in total) were created for the liver and lung cases in a homogeneous phantom. Lateral profile measurements were obtained under both motion and no-motion conditions using a 2D ionization chamber array (2D-array) and EBT3 Gafchromic films on the CIRS dynamic platform. Breathing curves from the cubic plans were used to assess nine patterns of sine curves, with amplitudes of 5.0–10.0 mm (10.0–20.0 mm target motions) and periods of 3–6 sec. Patient field verifications were conducted using a representative patient curve with an average amplitude of 6.4 mm and period of 3.2 sec. Additional simulations were performed assuming a ± 10% change in assigned timestamps for the dose rate (DR), spot spill (0.08-s), and gate time delay (0.1-s) to evaluate the effect of parameter selection on our 4DDD models. The 4DDDs were compared with measured values using the 2D gamma index and absolute doses over that required for dosing 95% of the target.
Results: The 2D-array measurements showed that average gamma scores for the reference (no motion) and 4DDD plans for all GWs were at least 99.9 ± 0.2% and 98.2 ± 2.4% at 3%/3 mm, respectively. The gamma scores of the 4DDDs in film measurements exceeded 95.4% and 92.9% at 2%/2 mm for the cubic and patient plans, respectively. The 4DDD calculations were acceptable under DR changes of ±10% and both spill and gate time delays of ±0.18 sec. For the 4DDD plan using all GWs for all measurement points, the absolute point differences for all validation plans were within ±5.0% for 99.1% of the points.
Conclusions: The RG-4DDD calculations (less than 50% GW) of the heterogeneous and actual patient plans showed good agreement with measurements for various breathing curves in the amplitudes and periods described above. The proposed system allows us to evaluate actual RG irradiation without requiring the ability to record spot timestamps
Rare internal hernia following pancreatoduodenectomy: A case report
Introduction: Pancreatoduodenectomy (PD) is a complex procedure with a high morbidity rate. Internal hernia following PD is a rare but potentially life-threatening complication. Herein, we describe a rare case of internal hernia after PD.
Presentation of case: A 76-year-old man who underwent subtotal stomach-preserving PD 7 years ago presented with vomiting and abdominal pain. Abdominal computed tomography revealed an internal hernia. Because conservative treatment failed, surgical intervention was performed. Intraoperative findings revealed efferent loop herniation in the space between the afferent loop near the Braun anastomosis and transverse mesocolon. The hernia was repositioned and the mesenteric defect was closed.
Discussion: This is an extremely rare case of an internal hernia that developed 7 years after PD. As conservative management provides a little chance for improvement, precise diagnosis and prompt re-intervention are essential for the management of internal hernia. In this case, the hernial orifice developed in the space between the afferent and efferent loops and the transverse mesocolon. Internal hernia could be a differential diagnosis in patients with ileus after PD.
Conclusion: This study provided a detailed description of an extremely rare case of internal hernia following PD. Therefore, internal hernias should be considered in patients undergoing PD
Activated factor X inhibition ameliorates NF-κB-IL-6-mediated perivascular inflammation and pulmonary hypertension
Activated factor X (FXa) induces inflammatory response and cell proliferation in various cell types via activation of proteinase-activated receptor-1 (PAR1) and/or PAR2. We thus aimed to investigate the impact of FXa on the development of pulmonary arterial hypertension (PAH) and the mechanisms involved. The effects of edoxaban, a selective FXa inhibitor, on hemodynamic, right ventricular (RV) hypertrophy, and vascular remodeling were evaluated in a monocrotaline (MCT)-exposed pulmonary hypertension (PH) rat model. At 21 days after a single subcutaneous injection of MCT of 60 mg/kg, right ventricular systolic pressure (RVSP) and total pulmonary vascular resistance index (TPRI) were elevated concomitant with the increased plasma FXa and lung interleukin-6 (IL-6) mRNA. Daily administration of edoxaban (10 mg/kg/day, by gavage) starting from the day of MCT injection for 21 days ameliorated RVSP, TPRI, RV hypertrophy, pulmonary vascular remodeling, and macrophage accumulation. Edoxaban reduced nuclear factor-kappa B (NF-κB) activity and IL-6 mRNA level in the lungs of MCT-exposed rats. mRNA levels of FXa, PAR1, and PAR2 in cultured pulmonary arterial smooth muscle cells (PASMCs) isolated from patients with PAH were higher than those seen in normal PASMCs. FXa stimulation increased cell proliferation and mRNA level of IL-6 in normal PASMCs, both of which were blunted by edoxaban and PAR1 antagonist. Moreover, FXa stimulation activated extracellularly regulated kinases 1/2 in a PAR1-dependent manner. Inhibition of FXa ameliorates NF-κB-IL-6-mediated perivascular inflammation, pulmonary vascular remodeling, and the development of PH in MCT-exposed rats, suggesting that FXa may be a potential target for the treatment of PAH.
NEW & NOTEWORTHY This study demonstrated that chronic treatment with activated factor X (FXa) inhibitor ameliorated NF-κB-IL-6-mediated perivascular inflammation in a rat model with pulmonary arterial hypertension, which is associated with elevated FXa activity. FXa may act on pulmonary arterial smooth muscle cells, inducing cell proliferation and inflammatory response via upregulated PAR1, thereby contributing to pulmonary vascular remodeling. Understanding the patient-specific pathophysiology is a prerequisite for applying FXa-targeted therapy to the treatment of pulmonary arterial hypertension
Study on the Removal Technology of Trichloramine from Drinking Water Using Ultraviolet Light
Trichloramine (NCl3) is an inorganic chloramine that causes a pungent chlorine-like odor, and it is difficult to remove its precursors (nitrogen organic compounds and/or ammonia) completely from water. Powdered activated carbon, ozonation, and UV treatment have been applied for decomposing NCl3, but free chlorine was also decomposed. So, it is necessary to develop a technique that can selectively control NCl3 without losing free chlorine. UV light-emitting diodes (265, 280, and 300 nm) and plasma emission UV sheet (347 ± 52 nm, hereafter 350 nm) were compared to find the optimal wavelengths that decompose NCl3 but not free chlorine. As a result, 90.6, 96.7, 92.5, and 77.8% of NCl3 were removed at 265, 280, 300 (3,600 mJ/cm2), and 350 nm (14,400 mJ/cm2), respectively. On the other hand, free chlorine at neutral pH (hypochlorous acid is dominant) and slightly alkaline pH (hypochlorite ion is dominant) was not decomposed at 350 nm, but at other wavelengths (i.e., 265, 280, and 300 nm) the removals were more than 64%. Therefore, UV radiation at 350 nm can be candidates to remove NCl3 while maintaining free chlorine. However, this method requires high input energy, and further study is needed for evaluating the practical applicability of this method by considering optimal reactor design
Global trends in mortality related to pulmonary embolism: an epidemiological analysis of data from the World Health Organization mortality database from 2001 to 2023
Association of the expression of 5‑FU biomarkers with aging and prognosis in elderly patients with lung cancer treated with S‑1 adjuvant chemotherapy: Follow‑up results of the Setouchi Lung Cancer Group Study 1201
Managing elderly patients presents several challenges because of age‑related declines; however, age should not be the sole determinant for adjuvant treatment decisions in patients with non‑small cell lung cancer (NSCLC). Moreover, age may affect the expression of 5‑fluorouracil (5‑FU) biomarkers. The present study assessed: i) The effect of age on the expression levels of 5‑FU biomarkers by analyzing a public database; and ii) the ability of these biomarkers to predict clinical outcomes in elderly patients with NSCLC who underwent complete resection in the Setouchi Lung Cancer Group Study 1201 (SCLG1201) followed by S‑1 adjuvant chemotherapy. Changes in gene expression levels across age groups were assessed by analyzing The Cancer Genome Atlas (TCGA) database. The expression of 5‑FU biomarkers, including thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), orotate phosphoribosyltransferase, epidermal growth factor receptor (EGFR) and excision repair cross‑complementation group 1 (ERCC1), were assessed via quantitative reverse‑transcription PCR assays in 89 elderly patients (≥75 years) with NSCLC who received adjuvant chemotherapy with oral fluoropyrimidine prodrug S‑1 in the SLCG1201 trial. TCGA database analysis (n=955) showed that TS expression decreased significantly with aging, especially in the age group ≥75. In the SCLG1201 trial, univariate analysis revealed that EGFR upregulation and TS downregulation were correlated with favorable recurrence‑free survival (RFS) and overall survival (OS), respectively. Multivariate analysis demonstrated that pathological stage was an independent prognostic factor for both RFS and OS. EGFR mutations were associated with upregulation of DPD and EGFR, and downregulation of TS and ERCC1. In conclusion, although pathological stage is an independent prognostic factor for survival, EGFR upregulation and TS downregulation may be a greater predictor of clinical outcomes in elderly patients with NSCLC treated with S‑1 adjuvant chemotherapy. The age‑related decrease in TS expression supports the potential benefit of 5‑FU therapies in elderly patients. Nonetheless, further research is warranted to validate these results
Synergistic Antimicrobial Activity of BrSPR20-P1 Peptide and Silver Nanoparticles Against Pathogenic Bacteria
Bacterial infection is a cause of life-threatening diseases. The emergence of antimicrobial-resistant bacteria exacerbates this situation, highlighting the need for the discovery of new antimicrobial agents. Our previous study identified a novel antimicrobial peptide, BrSPR20-P1 (P1), which showed potential activity against MRSA. Additionally, silver nanoparticles (AgNPs) exhibit broad-spectrum antibacterial activity, capable of killing multidrug-resistant bacteria. The combination of antimicrobial agents presents a novel strategy for combating these pathogens. This study aimed to evaluate the antibacterial activity of the combination of P1 and AgNPs. It revealed that the combinations showed synergy. The P1 and AgNP mixture at a concentration of 1 and 8 µg/mL (1:8) doubled the activity against S. aureus and MRSA, while that combination of 64 and 64 µg/mL (64:64) exhibited broad-spectrum activity, expanding to E. coli with a 32-fold increase. These combinations exhibited a bactericidal effect, showing the rapid killing of tested bacteria at 10× MIC, with killing rates during the first 3 h ranging from 4.04 ± 0.01 to 4.31 ± 0.03 h−1. The P1 and AgNP mixtures caused a low risk of antibacterial resistance up to 30 passages. It was demonstrated that the synergistic activity of P1 and AgNPs occurred through the disruption of cell walls and membranes, leakage of intracellular materials, and cell lysis. Additionally, the mixtures appeared to interact with bacterial genomic DNA, as indicated by a gel retardation assay. These activities of the combinations were concentration-dependent. The 1:8 µg/mL mixture caused low hemolysis and cytotoxicity and did not impede the wound healing process. In contrast, although the 64:64 µg/mL mixture showed excellent antibacterial efficacy, it was toxic to erythrocytes and mammalian cells. It implies that dose optimization is required to balance its efficacy and toxicity. Therefore, the P1 and AgNP combinations exhibit synergistic antimicrobial activity and have the potential to resolve bacterial infections
Intracranial activity of sotorasib vs docetaxel in pretreated KRAS G12C-mutated advanced non-small cell lung cancer from a global, phase 3, randomized controlled trial
Objectives: To assess the efficacy and safety of sotorasib in patients with brain metastases using data from the phase 3 CodeBreaK 200 study, which evaluated sotorasib in adults with pretreated advanced or metastatic KRAS G12C-mutated non-small cell lung cancer (NSCLC).
Materials and methods: Patients with KRAS G12C-mutated NSCLC who progressed after platinum-based chemotherapy and checkpoint inhibitor therapy were randomized 1:1 to sotorasib or docetaxel. An exploratory post-hoc analysis evaluated central nervous system (CNS) progression-free survival (PFS) and time to CNS progression in patients with treated and stable brain metastases at baseline. Measures were assessed by blinded independent central review per study-modified Response Assessment in Neuro-Oncology Brain Metastases (RANO-BM) criteria.
Results: Of the patients randomly assigned to receive sotorasib (n=171) or docetaxel (n=174), baseline CNS metastases were present in 40 (23%) and 29 (17%) patients, respectively. With a median follow-up of 20.0 months for this patient subgroup, median CNS PFS was longer with sotorasib compared with docetaxel (9.6 vs 4.5 months; hazard ratio, 0.43 [95% CI, 0.20–0.92]; P=0.02). Among patients with baseline treated CNS lesions of ≥10 mm, the percentage of patients who achieved CNS tumor shrinkage of ≥30% was two-fold higher with sotorasib than docetaxel (33.3% vs 15.4%). Treatment-related adverse events among patients with CNS lesions at baseline were consistent with those of the overall study population.
Conclusions: These results suggest intracranial activity with sotorasib complements the overall PFS benefit observed with sotorasib vs docetaxel, with safety outcomes similar to those in the general CodeBreaK 200 population.
Clinical trials registration number: NCT04303780
A cross-sectional interventional study on the effects of periodontal treatment on periodontal inflamed surface area and masticatory efficiency values according to the 2018 periodontal status classification
Background Periodontal inflamed surface area (PISA) and masticatory efficiency have been used to evaluate the relationship between systemic diseases and oral diseases. However, clear standards for PISA values and masticatory efficiency in relation to the severity of periodontitis are lacking. This study aims to evaluate PISA values and masticatory efficiency based on the 2018 periodontal status classification system.
Methods In total, 153 healthy participants diagnosed with periodontitis were included in the study. The diagnosis was based on the 2018 periodontal status classification. PISA values and masticatory efficiency were measured at baseline and after initial periodontal therapy.
Results PISA demonstrated a higher area under the curve for Stage III (0.815) and Grade B (0.85). At baseline, PISA was showed significant negative correlation with masticatory efficiency (B coefficient [95% CI]: -0.02 [-0.03, -0.006], p
Conclusion Periodontal therapy improved PISA and masticatory efficiency values. However, the extent of improvement was less pronounced in patients with higher stages and grades of periodontitis. It is essential to consider the interplay between increased PISA and decreased masticatory efficiency when treating patients with severe periodontitis
Oestrogen replacement combined with resistance exercise in older women with knee osteoarthritis: a randomised, double-blind, placebo-controlled clinical trial
Background: Interventions targeting physical function decline in older women with knee osteoarthritis (KOA) are vital for healthy ageing. The additive benefits of combining oestrogen replacement therapy (ERT) with resistance exercise remain unclear.
Objective: To evaluate the additive effect of low-dose ERT on physical performance when combined with a muscle resistance exercise programme (MREP) in older women with KOA.
Design: This is a placebo-controlled, double-blind, randomised clinical trial.
Subjects: The subjects were community-dwelling women aged ≥65 years with chronic knee pain and KOA diagnosis.
Methods: Participants completed a 3-month MREP and were randomised to receive daily low-dose transdermal ERT (oestradiol 0.54 mg/day) or placebo. Outcomes were assessed at baseline, postintervention and 12 months later. The primary outcome was change in 30-second chair stand test (CS-30) score. Secondary outcomes included muscle mass, knee extension strength, walking performance, metabolic indicators, knee pain scale and 12-item short-form health survey (SF-12). Between-group differences in CS-30 changes were analysed using a linear regression model based on the intention-to-treat principle.
Results: Among 168 individuals screened, 75 participants (mean age 73.8 years, SD 5.8) were enrolled and randomised into an ERT group (n = 37) or a placebo group (n = 38). Baseline CS-30 scores were 14.81 (SD 3.95) in the ERT group and 15.58 (SD 3.48) in the placebo group. At 3 months, mean changes were 2.59 (SD 2.58) and 1.79 (SD 2.28) repetitions, respectively. The primary analysis showed no statistically significant between-group difference [regression coefficient: 0.81 (95% CI: −0.31, 1.92); P = .16]. Post hoc subgroup and sensitivity analyses suggested that benefits may exist among early-stage KOA participants. SF-12 mental health scores also improved significantly in the ERT group. No serious adverse events occurred.
Conclusions: ERT did not confer significant additive benefits to resistance exercise overall but may improve outcomes in early-stage KOA and mental health domains. These exploratory findings warrant further investigation