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Physiologia Plantarum 2024In recent years, there has been an increase in the study of phytomelatonin. Having numerous functions in animals, melatonin produced by plants (phytomelatonin) is also a... (Review)
Review
In recent years, there has been an increase in the study of phytomelatonin. Having numerous functions in animals, melatonin produced by plants (phytomelatonin) is also a multi-regulatory molecule with great potential in plant physiology and in mitigating abiotic stresses, such as drought, salinity, chilling, heat, chemical contamination, and UV-radiation stress. This review highlights the primary functions of phytomelatonin as an anti-stress molecule against abiotic stress. We discuss the role of phytomelatonin as a master regulator, oxidative stress manager, reactive oxygen species and reactive nitrogen species regulator, and defense compounds inducer. Although there exist a handful of reviews on the crosstalk of phytomelatonin with other signaling molecules like auxin, cytokinin, gibberellin, abscisic acid, ethylene, nitric oxide, jasmonic acid, and salicylic acid, this review looks at studies that have reported a few aspects of phytomelatonin with newly discovered signaling molecules along with classical signaling molecules with relation to abiotic stress tolerance. The research and applications of phytomelatonin with hydrogen sulfide, strigolactones, brassinosteroids, and polyamines are still in their nascent stage but hold a promising scope for the future. Additionally, this review states the recent developments in the signaling of phytomelatonin with nitrogen metabolism and nitrosative stress in plants.
Topics: Melatonin; Homeostasis; Stress, Physiological; Signal Transduction; Plants; Plant Physiological Phenomena; Plant Growth Regulators
PubMed: 38924553
DOI: 10.1111/ppl.14413 -
Biomedical Physics & Engineering Express Jun 2024: To summarize our institutional prostate stereotactic body radiation therapy (SBRT) experience using auto beam hold (ABH) technique for intrafractional prostate motion...
: To summarize our institutional prostate stereotactic body radiation therapy (SBRT) experience using auto beam hold (ABH) technique for intrafractional prostate motion and assess ABH tolerance of 10-millimeter (mm) diameter.: Thirty-two patients (160 fractions) treated using ABH technique between 01/2018 and 03/2021 were analyzed. During treatment, kV images were acquired every 20-degree gantry rotation to visualize 3-4 gold fiducials within prostate to track target motion. If the fiducial center fell outside the tolerance circle (diameter = 10 mm), beam was automatically turned off for reimaging and repositioning. Number of beam holds and couch translational movement magnitudes were recorded. Dosimetric differences from intrafractional motion were calculated by shifting planned isocenter.: Couch movement magnitude (mean ± SD) in vertical, longitudinal and lateral directions were -0.7 ± 2.5, 1.4 ± 2.9 and -0.1 ± 0.9 mm, respectively. For most fractions (77.5%), no correction was necessary. Number of fractions requiring one, two, or three corrections were 15.6%, 5.6% and 1.3%, respectively. Of the 49 corrections, couch shifts greater than 3 mm were seen primarily in the vertical (31%) and longitudinal (39%) directions; corresponding couch shifts greater than 5 mm occurred in 2% and 6% of cases. Dosimetrically, 100% coverage decreased less than 2% for clinical target volume (CTV) (-1 ± 2%) and less than 10% for PTV (-10 ± 6%). Dose to bladder, bowel and urethra tended to increase (Bladder: ΔD10%:184 ± 466 cGy, ΔD40%:139 ± 241 cGy, Bowel: ΔD1 cm:54 ± 129 cGy; ΔD5 cm:44 ± 116 cGy, Urethra: ΔD0.03 cm:1 ± 1%). Doses to the rectum tended to decrease (Rectum: ΔD1 cm:-206 ± 564 cGy, ΔD10%:-97 ± 426 cGy; ΔD20%:-50 ± 251 cGy).: With the transition from conventionally fractionated intensity modulated radiation therapy to SBRT for localized prostate cancer treatment, it is imperative to ensure that dose delivery is spatially accurate for appropriate coverage to target volumes and limiting dose to surrounding organs. Intrafractional motion monitoring can be achieved using triggered imaging to image fiducial markers and ABH to allow for reimaging and repositioning for excessive motion.
Topics: Humans; Male; Prostatic Neoplasms; Radiosurgery; Prostate; Radiotherapy Dosage; Radiotherapy Planning, Computer-Assisted; Radiometry; Movement; Fiducial Markers; Motion; Dose Fractionation, Radiation; Radiotherapy, Intensity-Modulated; Urinary Bladder; Rectum; Organs at Risk
PubMed: 38923907
DOI: 10.1088/2057-1976/ad4b1d -
Radiation Oncology (London, England) Jun 2024Magnetic resonance guided radiotherapy (MRgRT) allows daily adaptation of treatment plans to compensate for positional changes of target volumes and organs at risk...
INTRODUCTION
Magnetic resonance guided radiotherapy (MRgRT) allows daily adaptation of treatment plans to compensate for positional changes of target volumes and organs at risk (OARs). However, current adaptation times are relatively long and organ movement occurring during the adaptation process might offset the benefit gained by adaptation. The aim of this study was to evaluate the dosimetric impact of these intrafractional changes. Additionally, a method to predict the extent of organ movement before the first treatment was evaluated in order to have the possibility to compensate for them, for example by adding additional margins to OARs.
MATERIALS & METHODS
Twenty patients receiving adaptive MRgRT for treatment of abdominal lesions were retrospectively analyzed. Magnetic resonance (MR) images acquired at the start of adaptation and immediately before irradiation were used to calculate adapted and pre-irradiation dose in OARs directly next to the planning target volume. The extent of organ movement was determined on MR images acquired during simulation sessions and adaptive treatments, and their agreement was evaluated. Correlation between the magnitude of organ movement during simulation and the duration of simulation session was analyzed in order to assess whether organ movement might be relevant even if the adaptation process could be accelerated in the future.
RESULTS
A significant increase in dose constraint violations was observed from adapted (6.9%) to pre-irradiation (30.2%) dose distributions. Overall, OAR dose increased significantly by 4.3% due to intrafractional organ movement. Median changes in organ position of 7.5 mm (range 1.5-10.5 mm) were detected within a median time of 17.1 min (range 1.6-28.7 min). Good agreement was found between the range of organ movement during simulation and adaptation (66.8%), especially if simulation sessions were longer and multiple MR images were acquired. No correlation was determined between duration of simulation sessions and magnitude of organ movement.
CONCLUSION
Intrafractional organ movement can impact dose distributions and lead to violations of OAR tolerance doses, which impairs the benefit of daily on-table plan adaptation. By application of simulation images, the extent of intrafractional organ movement can be predicted, which possibly allows to compensate for them.
Topics: Humans; Radiotherapy, Image-Guided; Radiotherapy Planning, Computer-Assisted; Retrospective Studies; Organs at Risk; Magnetic Resonance Imaging; Radiotherapy Dosage; Abdominal Neoplasms; Female; Male; Middle Aged; Aged; Radiotherapy, Intensity-Modulated; Movement; Dose Fractionation, Radiation
PubMed: 38918828
DOI: 10.1186/s13014-024-02466-x -
Gastric Cancer : Official Journal of... Jun 2024For the elderly patients with gastric cancer, it may be more challenging to tolerate complete neoadjuvant therapy (NAT). The impact of discontinued NAT on the surgical...
Discontinuation of neoadjuvant therapy does not influence postoperative short-term outcomes in elderly patients (≥ 70 years) with resectable gastric cancer: a population-based study from the dutch upper gastrointestinal cancer audit (DUCA) data.
BACKGROUND
For the elderly patients with gastric cancer, it may be more challenging to tolerate complete neoadjuvant therapy (NAT). The impact of discontinued NAT on the surgical safety and pathological outcomes of elderly patients with poor tolerance remains poorly understood.
METHODS
Gastric cancer patients received gastrectomy with curative intent from the Dutch upper GI cancer audit (DUCA) database were included in this study. The independent association of age with not initiating and discontinuation of NAT was assessed with restricted cubic splines (RCS). According to the RCS results, age ≥ 70 years was defined as elderly. Short-term postoperative outcomes and pathological results were compared between elderly patients who completed and discontinued NAT.
RESULTS
Between 2011- 2021, total of 3049 patients were included. The risk of not initiating NAT increased from 70 years. In 1954 (64%) patients receiving NAT, the risk of discontinuation increased from 55 years, reaching the peak around 74 years. In the elderly, discontinued NAT was not independently associated with worse 30-day mortality, overall complications, anastomotic leakage, re-intervention, and pathologic complete response, but was associated with a higher risk of R1/2 resection (p-value = 0.001), higher ypT stage (p-value = 0.004), ypN + (p-value = 0.008), and non-response ( p-value = 0.012).
CONCLUSION
A decreased utilization of NAT has been observed in Dutch gastric cancer patients from 70 years due to old age considerations, possibly because of their high risk of discontinuation. Increasing the utilization of NAT may not adversely impact the surgical safety of gastric cancer population ≥ 70 years and may contribute to better pathological results.
PubMed: 38918269
DOI: 10.1007/s10120-024-01522-5 -
Supportive Care in Cancer : Official... Jun 2024Radical radiotherapy (RT) is the cornerstone of Head and Neck (H&N) cancer treatment, but it often leads to fatigue due to irradiation of brain structures, impacting... (Review)
Review
INTRODUCTIONS
Radical radiotherapy (RT) is the cornerstone of Head and Neck (H&N) cancer treatment, but it often leads to fatigue due to irradiation of brain structures, impacting patient quality of life.
OBJECTIVE
This study aimed to systematically investigate the dose correlates of fatigue after H&N RT in brain structures.
METHODS
The systematic review included studies that examined the correlation between fatigue outcomes in H&N cancer patients undergoing RT at different time intervals and brain structures. PubMed, Scopus, and WOS databases were used in the systematic review. A methodological quality assessment of the included studies was conducted following the PRISMA guidelines. After RT, the cohort of H&N cancer patients was analyzed for dose correlations with brain structures and substructures, such as the posterior fossa, brainstem, cerebellum, pituitary gland, medulla, and basal ganglia.
RESULT
Thirteen studies meeting the inclusion criteria were identified in the search. These studies evaluated the correlation between fatigue and RT dose following H&N RT. The RT dose ranged from 40 Gy to 70 Gy. Most of the studies indicated a correlation between the trajectory of fatigue and the dose effect, with higher levels of fatigue associated with increasing doses. Furthermore, five studies found that acute and late fatigue was associated with dose volume in specific brain structures, such as the brain stem, posterior fossa, cerebellum, pituitary gland, hippocampus, and basal ganglia.
CONCLUSION
Fatigue in H&N RT patients is related to the radiation dose received in specific brain areas, particularly in the posterior fossa, brain stem, cerebellum, pituitary gland, medulla, and basal ganglia. Dose reduction in these areas may help alleviate fatigue. Monitoring fatigue in high-risk patients after radiation therapy could be beneficial, especially for those experiencing late fatigue.
Topics: Humans; Head and Neck Neoplasms; Fatigue; Radiotherapy Dosage; Quality of Life; Dose-Response Relationship, Radiation; Brain
PubMed: 38918218
DOI: 10.1007/s00520-024-08655-4 -
ACS Omega Jun 2024Lead halide perovskites have been extensively studied for their potential applications, including photodetectors, solar cells, and high-energy radiation detection. These...
Lead halide perovskites have been extensively studied for their potential applications, including photodetectors, solar cells, and high-energy radiation detection. These applications are possible because of their unique optoelectronic properties, such as tunable band gap, high optical absorption coefficient, and unique defect self-healing properties, which result in high defect tolerance. Despite these advantages, the long-term stability remains a critical issue that could hinder commercial applications of these materials. Reports on the stability of lead halide perovskites for optoelectronic applications have normally focused on methylammonium (MA)/formamidinium (FA), with very limited information for other systems, in particular, Cs-containing perovskites. In this paper, we report the stability of thick CsPbBr Cl polycrystalline thin films (∼8 μm) with several halide Br-Cl ratios after exposure to deep UV radiation. The chemical, crystal structure, optical, and electrical properties are analyzed, and the results are used to propose a degradation mechanism. The chemical analysis on the surface and bulk of the films indicates the formation of cesium oxide after UV exposure, with no significant change in the crystalline structure. The proposed mechanism explains the formation of cesium oxides during UV exposure. The - characteristics of diode structures also showed significant degradation after UV exposure, primarily at lower diode rectification ratios. The mechanism proposed in this paper can contribute to developing strategies to enhance the long-term stability of inorganic lead halide perovskites under UV exposure.
PubMed: 38911782
DOI: 10.1021/acsomega.4c01461 -
Cureus May 2024Graves' disease (GD) is an autoimmune condition of the thyroid. The hyperthyroidism manifested by patients affected by this disease is caused by the production of... (Review)
Review
Graves' disease (GD) is an autoimmune condition of the thyroid. The hyperthyroidism manifested by patients affected by this disease is caused by the production of autoantibodies against the thyroid-stimulating hormone (TSH, or thyrotropin) receptor (TSHR), which mimic the effects of the hormone on thyroid cells, thereby stimulating autonomic production of thyroxine and triiodothyronine. Deciding on a therapeutic approach to this condition presents intricate dilemmas for both clinicians and patients. Each of the three available treatment modalities is grounded in evidence-based medicine, affirming its efficacy. This systematic review and meta-analysis aimed to assess the effect of carbimazole (CBM), radioactive iodine (RAI), and surgery in treating GD and provide evidence-based recommendations for healthcare providers regarding the optimal management of the condition based on a comprehensive analysis of effectiveness, safety, patient satisfaction, and recovery outcomes. This systematic review and meta-analysis adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We used the PubMed and Google Scholar databases to conduct a thorough web search for articles published between January 2019 and September 2023. The meta-analysis was carried out using Resource Manager (Revman) 5.4.1. The study found that propylthiouracil (PTU) or methimazole/carbimazole (MMI/CBM) treatment increases the risk of hyperlipidemia in patients with hyperthyroidism. Once in a euthyroid state, glucose tolerance increases; for children with GD, a computer model for customized dosing has been created. To sum up, CBM, surgery, and RAI are all useful treatment options for GD. Using steroids in conjunction with radiation therapy may help prevent Graves' ophthalmopathy (GO).
PubMed: 38910658
DOI: 10.7759/cureus.60829 -
Clinical & Translational Oncology :... Jun 2024Surgery is the standard treatment for pancreatic neuroendocrine tumors (pNETs), obtaining favorable results but associating high morbidity and mortality rates. This...
INTRODUCTION
Surgery is the standard treatment for pancreatic neuroendocrine tumors (pNETs), obtaining favorable results but associating high morbidity and mortality rates. This study assesses stereotactic body radiation therapy (SBRT) as a radical approach for small (< 2 cm) nonfunctioning pNETs.
MATERIALS AND METHODS
From January 2017 to June 2023, 20 patients with small pNETs underwent SBRT in an IRB-approved study. Endpoints included local control, tolerance, progression-free survival, and overall survival (OS). Diagnostic assessments comprised endoscopy, CT scans, OctreScan or PET-Dotatoc, abdominal MRI, and histological confirmatory samples.
RESULTS
In a 30-month follow-up of 20 patients (median age 55.5 years), SBRT was well-tolerated with no grade > 2 toxicity. 40% showed morphological response, 55% remained stable. Metabolically, 50% achieved significant improvement. With a median OS of 41.5 months, all patients were alive without local or distant progression or need for surgical resection.
CONCLUSION
SBRT is a feasible and well-tolerated approach for small neuroendocrine pancreatic tumors, demonstrating effective local control. Further investigations are vital for validation and extension of these findings.
PubMed: 38907097
DOI: 10.1007/s12094-024-03538-w -
BMJ Open Jun 2024This study aimed at investigating the relationship between occupational exposure to external ionising radiation and central nervous system (CNS) tumours mortality in...
OBJECTIVE
This study aimed at investigating the relationship between occupational exposure to external ionising radiation and central nervous system (CNS) tumours mortality in healthcare workers working in France.
DESIGN AND SETTING
The Occupational Radiation-Induced Cancer in Medical staff (ORICAMs) nested case-control study was conducted based on the dosimetric records of the national register of occupational dosimetry (Système d'information de la surveillance de l'exposition aux rayonnements ionisants).
PARTICIPANTS AND METHODS
33 CNS tumour deaths occurred between 2002 and 2012 among the ORICAMs cohort composed of 164 015 healthcare workers. Each case was matched to five controls alive at the time of the corresponding case's death, based on sex, year of birth, date of enrolment in the cohort and duration of follow-up. All participants were badge monitored for external radiation exposure, expressed in H(10). Conditional logistic regression was used to analyse the dose-response relationship between radiation dose and CNS mortality.
RESULTS
Cases were exposed to a mean cumulative career radiation dose of 5.8±13.7 (max: 54.3) millisievert (mSv) compared with 4.1±15.2 (142.2) mSv for controls. No statistically significant association was found between CNS tumour mortality and cumulative whole-body career dose (OR=1.00, 95% CI 0.98 to 1.03), duration of exposure (OR=1.03; 95% CI 0.95 to 1.12) or age at first exposure (OR=0.98; 95% CI 0.91 to 1.06).
CONCLUSION
We found no evidence of an association between external radiation exposure and CNS tumour risk in healthcare workers. Limitations of the study include low statistical power and short duration of follow-up.
Topics: Humans; Occupational Exposure; Case-Control Studies; France; Male; Female; Health Personnel; Adult; Middle Aged; Central Nervous System Neoplasms; Radiation, Ionizing; Neoplasms, Radiation-Induced; Occupational Diseases; Dose-Response Relationship, Radiation; Logistic Models; Risk Factors; Radiation Exposure
PubMed: 38904132
DOI: 10.1136/bmjopen-2024-084285 -
BMC Plant Biology Jun 2024Light deficit in shaded environment critically impacts the growth and development of turf plants. Despite this fact, past research has predominantly concentrated on...
BACKGROUND
Light deficit in shaded environment critically impacts the growth and development of turf plants. Despite this fact, past research has predominantly concentrated on shade avoidance rather than shade tolerance. To address this, our study examined the photosynthetic adjustments of Bermudagrass when exposed to varying intensities of shade to gain an integrative understanding of the shade response of C4 turfgrass.
RESULTS
We observed alterations in photosynthetic pigment-proteins, electron transport and its associated carbon and nitrogen assimilation, along with ROS-scavenging enzyme activity in shaded conditions. Mild shade enriched Chl b and LHC transcripts, while severe shade promoted Chl a, carotenoids and photosynthetic electron transfer beyond Q (ET/RC, φE, Ψ). The study also highlighted differential effects of shade on leaf and root components. For example, Soluble sugar content varied between leaves and roots as shade diminished SPS, SUT1 but upregulated BAM. Furthermore, we observed that shading decreased the transcriptional level of genes involving in nitrogen assimilation (e.g. NR) and SOD, POD, CAT enzyme activities in leaves, even though it increased in roots.
CONCLUSIONS
As shade intensity increased, considerable changes were noted in light energy conversion and photosynthetic metabolism processes along the electron transport chain axis. Our study thus provides valuable theoretical groundwork for understanding how C4 grass acclimates to shade tolerance.
Topics: Photosynthesis; Cynodon; Acclimatization; Plant Leaves; Electron Transport; Gene Expression Regulation, Plant; Nitrogen; Plant Roots; Plant Proteins; Chlorophyll
PubMed: 38902617
DOI: 10.1186/s12870-024-05242-x