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Food Research International (Ottawa,... Aug 2024There is an increasing amount of research into the development of a third generation of iron supplementation using peptide-iron chelates. Peptides isolated from mung...
There is an increasing amount of research into the development of a third generation of iron supplementation using peptide-iron chelates. Peptides isolated from mung bean were chelated with ferrous iron (MBP-Fe) and tested as a supplement in mice suffering from iron-deficiency anemia (IDA). Mice were randomly divided into seven groups: a group fed the normal diet, the IDA model group, and IDA groups treated with inorganic iron (FeSO), organic iron (ferrous bisglycinate, Gly-Fe), low-dose MBP-Fe(L-MBP-Fe), high-dose MBP-Fe(H-MBP-Fe), and MBP mixed with FeSO (MBP/Fe). The different iron supplements were fed for 28 days via intragastric administration. The results showed that MBP-Fe and MBP/Fe had ameliorative effects, restoring hemoglobin (HGB), red blood cell (RBC), hematocrit (HCT), and serum iron (SI) levels as well as total iron binding capacity (TIBC) and body weight gain of the IDA mice to normal levels. Compared to the inorganic (FeSO) and organic (Gly-Fe) iron treatments, the spleen coefficient and damage to liver and spleen tissues were significantly lower in the H-MBP-Fe and MBP/Fe mixture groups, with reparative effects on jejunal tissue. Gene expression analysis of the iron transporters Dmt 1 (Divalent metal transporter 1), Fpn 1 (Ferroportin 1), and Dcytb (Duodenal cytochrome b) indicated that MBP promoted iron uptake. These findings suggest that mung bean peptide-ferrous chelate has potential as a peptide-based dietary supplement for treating iron deficiency.
Topics: Animals; Vigna; Anemia, Iron-Deficiency; Biological Availability; Mice; Ferrous Compounds; Peptides; Iron; Male; Iron Chelating Agents; Hemoglobins; Dietary Supplements; Cation Transport Proteins; Disease Models, Animal; Glycine
PubMed: 38945571
DOI: 10.1016/j.foodres.2024.114602 -
Radiotherapy and Oncology : Journal of... Jun 2024Sacrococcygeal chordomas have high recurrence rates and are challenging to treat.
INTRODUCTION
Sacrococcygeal chordomas have high recurrence rates and are challenging to treat.
METHODS
In this phase II prospective, randomized, stratified trial, the safety and feasibility of hypofractionated ion radiation therapy were investigated. The primary focus was monitored through the incidence of Grade 3-5 NCI-CTC-AE toxicity. Secondary endpoints included local progression-free (LPFS) and overall survival (OS).
RESULTS
The study enrolled 82 patients with primary (87 %) and recurrent (13 %) inoperable or incompletely resected sacral chordomas from January 2013 to July 2022, divided equally into proton therapy (Arm A) and carbon ion beam therapy (Arm B) groups, each receiving a total dose of 64 Gy (RBE) in 16 fractions, 5-6 fractions per week. Overall 74 % of patients received no previous surgery and 66 % of tumors were confirmed by a brachyury staining. The mean and median Gross Tumor Volume at the time of treatment (GTV) was 407 ml and 185 ml, respectively. The median follow-up of the surviving patients was 44.7 months, and the 2-year and 4-year OS rates were 96 % and 81 %, respectively. Factors such as smaller GTV and younger age trended towards better OS. The LPFS after 2-year and 4-year was 84 % and 70 %, respectively. Male gender emerged as a significant predictor of LPFS. There was no significant difference between the treatment groups. We observed five grade IV wound healing disorders (6 %).
CONCLUSION
The initial response rates were promising; however local control was not sustained. More comparative research on fractionation schemes is essential to refine treatment approaches for inoperable sacral chordoma.
PubMed: 38944346
DOI: 10.1016/j.radonc.2024.110418 -
Japanese Journal of Clinical Oncology Jun 2024Proton beams deposit energy along their path, abruptly stopping and generating various radioactive particles, including positrons, along their trajectory. In comparison...
BACKGROUND
Proton beams deposit energy along their path, abruptly stopping and generating various radioactive particles, including positrons, along their trajectory. In comparison with traditional proton beam therapy, scanning proton beam therapy is effective in delivering proton beams to irregularly shaped tumors, reducing excessive radiation exposure to the alimentary tract during the treatment of liver cancer.
METHODS
In this study, we utilized positron emission tomography/computed tomography (PET/CT) imaging to assess the total amount of radiation to the alimentary tract during liver cancer treatment with proton beam therapy, involving the administration of complex irradiation in 13 patients.
RESULTS
This approach resulted in the prevention of excess radiation. The planned radiation restraint doses for the colon exhibited a significant correlation with the PET values of the colon (correlation coefficient 0.8384, P = .0003). Likewise, the scheduled radiation restraint doses for the gastroduodenum were correlated with the PET values of the gastroduodenum (correlation coefficient 0.5397, P = .0569).
CONCLUSIONS
PET/CT conducted after proton beam therapy is useful for evaluating excess radiation in the alimentary tract. Proton beam therapy in liver cancer, assessed via PET/CT, effectively reduced alimentary tract radiation, which is vital for optimizing treatments and preventing excess exposure.
PubMed: 38943456
DOI: 10.1093/jjco/hyae085 -
Radiotherapy and Oncology : Journal of... Jun 2024To investigate quality assurance (QA) techniques for in vivo dosimetry and establish its routine uses for proton FLASH small animal experiments with a saturated monitor...
PURPOSE
To investigate quality assurance (QA) techniques for in vivo dosimetry and establish its routine uses for proton FLASH small animal experiments with a saturated monitor chamber.
METHODS AND MATERIALS
227 mice were irradiated at FLASH or conventional (CONV) dose rates with a 250 MeV FLASH-capable proton beamline using pencil beam scanning to characterize the proton FLASH effect on abdominal irradiation and examining various endpoints. A 2D strip ionization chamber array (SICA) detector was positioned upstream of collimation and used for in vivo dose monitoring during irradiation. Before each irradiation series, SICA signal was correlated with the isocenter dose at each delivered dose rate. Dose, dose rate, and 2D dose distribution for each mouse were monitored with the SICA detector.
RESULTS
Calibration curves between the upstream SICA detector signal and the delivered dose at isocenter had good linearity with minimal R values of 0.991 (FLASH) and 0.985 (CONV), and slopes were consistent for each modality. After reassigning mice, standard deviations were less than 1.85 % (FLASH) and 0.83 % (CONV) for all dose levels, with no individual subject dose falling outside a ± 3.6 % range of the designated dose. FLASH fields had a field-averaged dose rate of 79.0 ± 0.8 Gy/s and mean local average dose rate of 160.6 ± 3.0 Gy/s. In vivo dosimetry allowed for the accurate detection of variation between the delivered and the planned dose.
CONCLUSION
In vivo dosimetry benefits FLASH experiments through enabling real-time dose and dose rate monitoring allowing mouse cohort regrouping when beam fluctuation causes delivered dose to vary from planned dose.
PubMed: 38942121
DOI: 10.1016/j.radonc.2024.110404 -
Radiotherapy and Oncology : Journal of... Jun 2024As no guidelines for pencil beam scanning (PBS) proton therapy (PT) of paediatric posterior fossa (PF) tumours exist to date, this study investigated planning techniques...
BACKGROUND AND PURPOSE
As no guidelines for pencil beam scanning (PBS) proton therapy (PT) of paediatric posterior fossa (PF) tumours exist to date, this study investigated planning techniques across European PT centres, with special considerations for brainstem and spinal cord sparing.
MATERIALS AND METHODS
A survey and a treatment planning comparison were initiated across nineteen European PBS-PT centres treating paediatric patients. The survey assessed all aspects of the treatment chain, including but not limited to delineations, dose constraints and treatment planning. Each centre planned two PF tumour cases for focal irradiation, according to their own clinical practice but based on common delineations. The prescription dose was 54 Gy(RBE) for Case 1 and 59.4 Gy(RBE) for Case 2. For both cases, planning strategies and relevant dose metrics were compared.
RESULTS
Seventeen (89 %) centres answered the survey, and sixteen (80 %) participated in the treatment planning comparison. In the survey, thirteen (68 %) centres reported using the European Particle Therapy Network definition for brainstem delineation. In the treatment planning study, while most centres used three beam directions, their configurations varied widely across centres. Large variations were also seen in brainstem doses, with a brainstem near maximum dose (D2%) ranging from 52.7 Gy(RBE) to 55.7 Gy(RBE) (Case 1), and from 56.8 Gy(RBE) to 60.9 Gy(RBE) (Case 2).
CONCLUSION
This study assessed the European PBS-PT planning of paediatric PF tumours. Agreement was achieved in e.g. delineation-practice, while wider variations were observed in planning approach and consequently dose to organs at risk. Collaboration between centres is still ongoing, striving towards common guidelines.
PubMed: 38942120
DOI: 10.1016/j.radonc.2024.110414 -
Physics in Medicine and Biology Jun 2024Proton therapy is a limited resource and is typically not available to metastatic cancer patients. Combined proton-photon therapy (CPPT), where most fractions are...
Proton therapy is a limited resource and is typically not available to metastatic cancer patients. Combined proton-photon therapy (CPPT), where most fractions are delivered with photons and only few with protons, represents an approach to distribute proton resources over a larger patient population. In this study, we consider stereotactic radiotherapy of multiple brain or liver metastases, and develop an approach to optimally take advantage of a single proton fraction by optimizing the proton and photon dose contributions to each individual metastasis. CPPT treatments must balance two competing goals: 1) deliver a larger dose in the proton fractions to reduce integral dose, and 2) fractionate the dose in the normal tissue between metastases, which requires using the photon fractions. Such CPPT treatments are generated by simultaneously optimizing IMPT and IMRT plans based on their cumulative biologically effective dose (BED). The dose contributions of the proton and photon fractions to each individual metastasis are handled as additional optimization variables in the optimization problem. The method is demonstrated for two patients with 29 and 30 brain metastases, and two patients with 4 and 3 liver metastases. Optimized CPPT plans increase the proton dose contribution to most of the metastases, while using photons to fractionate the dose around metastases which are large or located close to critical structures. On average, the optimized CPPT plans reduce the mean brain BEDby 29% and the mean liver BEDby 42% compared to IMRT-only plans. Thereby, the CPPT plans approach the dosimetric quality of IMPT-only plans, for which the mean brain BEDand mean liver BEDare reduced by 28% and 58%, respectively, compared to IMRT-only plans. CPPT with optimized proton and photon dose contributions to individual metastases may benefit selected metastatic cancer patients without tying up major proton resources. .
PubMed: 38942008
DOI: 10.1088/1361-6560/ad5d48 -
Physics in Medicine and Biology Jun 2024Particle therapy treatments are currently limited by uncertainties of the delivered dose. Verification techniques like Prompt-Gamma-Timing-based Stopping Power...
Particle therapy treatments are currently limited by uncertainties of the delivered dose. Verification techniques like Prompt-Gamma-Timing-based Stopping Power Estimation (PGT-SPE) may allow for reduction of safety margins in treatment planning. Approach: From Prompt-Gamma-Timing measurements, we reconstruct the spatiotemporal distribution of prompt gamma emissions, which is linked to the average motion of the primary particles. The stopping power is determined by fitting a model of the average particle motion. Here, we compare a previously published implementation of the particle motion model with an alternative formulation and present two formulations to automatically select the hyperparameters of our procedure. The performance was assessed using Monte-Carlo simulations of proton beams (60 MeV to 219 MeV) impinging on a homogeneous PMMA phantom. Main results: The range was successfully determined within a standard deviation of 3 mm for proton beam energies from 70 MeV to 219 MeV. Stopping power estimates showed errors below 5 % for beam energies above 160 MeV. At lower energies, the estimation performance degraded to unsatisfactory levels due to the short range of the protons. The new motion model improved the estimation performance by up to 5 % for beam energies from 100 MeV to 150 MeV with mean errors ranging from 6 % to 18 %. The automated hyperparameter optimization matched the average error of previously reported manual selections, while significantly reducing the outliers. Significance: The data-driven hyperparameter optimization allowed for a reproducible and fast evaluation of our method. The updated motion model and evaluation at new beam energies bring us closer to applying PGT-SPE in more complex scenarios. Direct comparison of stopping power estimates between treatment planning and measurements during irradiation would offer a more direct verification than other secondary-particle-based techniques.
PubMed: 38941994
DOI: 10.1088/1361-6560/ad5d4b -
Oral Oncology Jun 2024
PubMed: 38941874
DOI: 10.1016/j.oraloncology.2024.106912 -
Przeglad Gastroenterologiczny 2024The eradication rate of () has decreased due to antibiotics resistance and inadequate acid suppression. Vonoprazan is a novel potassium-competitive acid blocker...
INTRODUCTION
The eradication rate of () has decreased due to antibiotics resistance and inadequate acid suppression. Vonoprazan is a novel potassium-competitive acid blocker (P-CAB), which has a rapid and sustained acid inhibitory effect and may be more effective than conventional proton pump inhibitors (PPIs) in eradication.
AIM
to study the efficacy and safety of vonoprazan as a component of first-line eradication treatment compared with conventional PPI-based therapy.
MATERIAL AND METHODS
This randomised (one to one) non-blinded study was conducted on 400 consecutive proven infected patients, of whom 200 received vonoprazan-based triple therapy, while 200 patients received PPI-based triple therapy for 14 days. The study outcomes were evaluated as eradication rate and adverse events in both patient groups.
RESULTS
The eradication rate was 86% in the vonoprazan group and 74.5% in the PPI group. The vonoprazan eradication rate was significantly higher than that of PPIs ( = 0.004). There was no significant difference regarding adverse events between both patient groups.
CONCLUSIONS
Vonoprazan-based therapy was more effective than PPI-based therapy as a first-line eradication treatment. Vonoprazan was generally safe and well tolerated.
PubMed: 38939071
DOI: 10.5114/pg.2024.139426 -
Przeglad Gastroenterologiczny 2024Proton pump inhibitors (PPIs) are effective drugs used for multiple gastrointestinal complications. They are commonly used in both hospitalised and outpatients. However,...
INTRODUCTION
Proton pump inhibitors (PPIs) are effective drugs used for multiple gastrointestinal complications. They are commonly used in both hospitalised and outpatients. However, little is known about its utilisation pattern in ambulatory patients.
AIM
To evaluate the inexpedient continuous use of PPIs in patients with respect to treatment duration.
MATERIAL AND METHODS
A cross-sectional observational study was conducted from January 2018 to November 2019 in Khyber Pakhtunkhwa, Pakistan. Regular proton pump inhibitor users were identified through patient histories.
RESULTS
During the study period, 171 patients were included using a non-probability consecutive sampling technique, who were using regular proton pump inhibitors for a longer duration, i.e. from 3 months to 15 years. The highest proportion (42.8%) were using PPI regularly from 3 months to 1 year followed by 22.9% for 1-2 years, 12.0% for 2-3 years, 7.8% for 3-4 years, 4.2% for 4-5 years, and 10.24% for > 5 years. Omeprazole and esomeprazole were the most commonly used drugs, with 71.1% and 23.5% prevalence, respectively. A total of 33.73% of patients had continued PPI use on their own after initially being prescribed by the physician.
CONCLUSIONS
It can be deduced that PPIs are used in outpatients beyond standard treatment guidelines. The inexpedient continuous use of proton pump inhibitors is of concern due to the risk of developing adverse effects. Therefore, patient counselling and periodic monitoring must be carried out to prevent the irrational use of PPIs.
PubMed: 38939068
DOI: 10.5114/pg.2024.139429