Publications by authors named "Toutain J"
Injectable Biocompatible Zeolite Nanocrystals for Enhanced Tumor Oxygenation and MRI Imaging.
ACS Appl Mater Interfaces
January 2025
Tumor hypoxia significantly limits the effectiveness of radiotherapy, as oxygen is crucial for producing cancer-killing reactive oxygen species. To address this, we synthesized nanosized faujasite (PBS-Na-FAU) zeolite crystals using clinical-grade phosphate-buffered saline (PBS) as the solvent, ensuring preserved crystallinity, microporous volume, and colloidal stability. The zeolite nanocrystals showed enhanced safety profiles and , and studies showed no apparent toxicity to animals.
View Article and Find Full Text PDFArticle Synopsis
- Radiotherapy for brain tumors can cause cognitive impairments, and this study explores how deformation-based morphometry (DBM) using Jacobian determinants can help detect vulnerable areas in the brain after radiation exposure in an animal model.
- Rats underwent whole-brain irradiation (WBI, 30 Gy), and a series of MRI tests over six months assessed both macroscopic and microscopic brain changes, focusing on cerebral blood volume and diffusion metrics.
- The results indicated specific brain regions, such as the corpus callosum and cortex, displayed both transient and lasting structural changes due to radiation, highlighting DBM's potential for identifying at-risk brain areas in future patient treatments.
Article Synopsis
- * In a study using PET imaging on glioblastoma models, the injected [Cu]-FAU nanocrystals accumulated rapidly in tumor areas while avoiding healthy brain tissue, with uptake kinetics varying between different glioblastoma models (U87-MG and U251-MG).
- * The research confirmed the presence of zeolite nanocrystals in the tumors and demonstrated the potential of this radiolabeling technique for precise PET tracking, supporting the use of zeolite nanocr
Article Synopsis
- The study investigates how different types of radiation therapy (X-ray vs. proton therapy) affect various circulating leucocyte (white blood cell) subpopulations in mice, particularly in the context of tumor tolerance.
- Findings indicate that X-ray radiation causes lymphopenia (a reduction in lymphocyte counts), while proton therapy does not significantly impact lymphoid subpopulations; however, there is an increase in neutrophil counts with proton exposure.
- The research highlights the complex relationship between radiation type, volume irradiated, dose rate, and their effects on immune cell populations, suggesting direct lymphocyte-killing effects are only a minor contributor to radiation-induced lymphopenia.
Article Synopsis
- - The study investigates the relationship between hypoxia and RASSF1A/Hippo signaling in non-small cell lung cancer (NSCLC) and its brain metastases, confirming that both are hypoxic with a specific marker, CAIX.
- - Severe hypoxia activates the YAP protein in bronchial epithelial cells, which promotes amoeboid migration and brain metastasis formation, while also showing that NDR2 kinase is overactive in metastatic NSCLC compared to localized cases.
- - The findings suggest that NDR2 could serve as a valuable biomarker to assess the risk of metastasis in NSCLC patients, as its expression can be routinely measured via immunohistochemistry on tumor samples.
Article Synopsis
- The study focused on understanding the tumor microenvironment (TME) of brain metastases (BM) from lung cancer, specifically looking at factors like hypoxia and redox state, which impact tumor growth and treatment resistance.
- In vitro experiments showed that lung cancer cells increased certain proteins in response to low oxygen levels (hypoxia), indicating metabolic and oxidative stress changes in the tumor tissue.
- Imaging techniques, particularly [Cu][Cu(ATSM)] PET, revealed significant differences in hypoxia levels and protein expressions between cortical and striatal brain metastases, highlighting the importance of this imaging method in tailoring treatment approaches based on tumor characteristics.
Article Synopsis
- - Cat Eye Syndrome (CES) is a rare genetic disorder linked to a marker chromosome from chromosome 22, leading to diverse symptoms including iris coloboma, anal atresia, and preauricular tags, but these are present in less than half of the cases.
- - An international study of 43 CES patients found that only 16% displayed all three classic symptoms, while 9% showed none; additional issues such as cardiac anomalies (51%) and intellectual disabilities (47%) were also common.
- - The study highlights the significance of supernumerary marker chromosomes (sSMC), found in 91% of cases, with many parents showing mild traits, emphasizing the need for genetic counseling regarding recurrence risks.
Physical Activity Attenuates Brain Irradiation-Associated Skeletal Muscle Damage in the Rat.
Int J Radiat Oncol Biol Phys
March 2024
Purpose: Radiation therapy for brain tumors increases patient survival. Nonetheless, side effects are increasingly reported such as cognitive deficits and fatigue. The etiology of fatigue remains poorly described.
View Article and Find Full Text PDFPurpose: To describe a patient with hypertensive herpetic uveitis complicated by arterial retinal occlusions and a decompression retinopathy revealing a sickle cell trait.
Study Design: Case report.
Results: A 24-year-old African man presented with a hypertensive herpetic keratouveitis.
Article Synopsis
- The study investigates acute ischemic stroke, focusing on distinguishing between the ischemic core and the potentially salvageable penumbra using a new MRI technique for measuring brain oxygen levels (S O -MRI).
- The research found a strong correlation between S O -MRI signals and PET imaging of hypoxic tissues, indicating that S O -MRI can effectively identify areas at risk in stroke cases.
- Results showed that S O -MRI could not only detect hypoxia but also predict the final extent of brain lesions, suggesting its potential as a tool for better patient treatment strategies in acute stroke scenarios.
Article Synopsis
- Two cases of multiple evanescent white dot syndrome (MEWDS) were reported following the BNT162b2 mRNA COVID-19 vaccine, highlighting a potential link between the vaccine and ocular issues.
- A 40-year-old male and a 23-year-old female both experienced blurred vision and findings similar to MEWDS in their left eye after receiving the vaccine.
- Imaging showed that the eye anomalies resolved on their own within six weeks, pointing to possible inflammation or immune response related to the vaccine as a cause for these effects.
Article Synopsis
- This study evaluated the effectiveness of 18 F-fludarabine (18 F-FLUDA) PET/CT in distinguishing between primary central nervous system lymphomas (PCNSLs) and glioblastoma multiformes (GBMs).
- Researchers examined patients with either untreated PCNSL, PCNSL treated with corticosteroids, or GBM, using MRI and two PET tracers (11 C-MET and 18 F-FLUDA).
- Results indicated that 18 F-FLUDA showed significant differences in uptake patterns between PCNSL and GBM, with specific parameters achieving 100% sensitivity and specificity, suggesting 18 F-FLUDA could be a valuable tool for diagnosis, despite potential interference from corticost
Article Synopsis
- The study aimed to assess ART outcomes for infertile men with balanced chromosomal rearrangements or Y-chromosome microdeletions and compare them to a control group, focusing on clinical pregnancy rates.
- In a retrospective case-control analysis at two university hospitals, results showed a clinical pregnancy rate of 28% for men with chromosomal rearrangements and 43% for those with Y-chromosome microdeletions, compared to 24% in the control group, which was not significantly different.
- The findings suggest that these genetic issues do not significantly impact clinical pregnancy rates in conventional ART, but further studies are needed for validation.
Article Synopsis
- The study investigates how retroviral integrase interacts with cellular chromatin to insert the retroviral genome into host chromosomes, focusing on the role of the cofactor LEDGF/p75.
- It reveals that retroviral integrase can independently recognize specific chromatin regions even without LEDGF/p75, but the cofactor can redirect integrase to different chromosome areas.
- The research enhances understanding of the chromatin-binding properties of integrase and LEDGF/p75, shedding light on how they work together to optimize the integration process during retroviral infection.
CRISPR-Cas9 is a promising technology for gene therapy. However, the ON-target genotoxicity of CRISPR-Cas9 nuclease due to DNA double-strand breaks has received little attention and is probably underestimated. Here we report that genome editing targeting globin genes induces megabase-scale losses of heterozygosity (LOH) from the globin CRISPR-Cas9 cut-site to the telomere (5.
View Article and Find Full Text PDFArticle Synopsis
- Lung cancer patients often suffer from brain metastases (BM), leading to poor survival rates even with treatments like surgery and radiation therapy.
- The study investigated the role of hypoxia (low oxygen conditions) in BM using various methods, including biopsies and advanced imaging techniques, showing it is a significant and varied characteristic of lung cancer BM.
- Hypoxia-image-guided radiotherapy (HIGRT) demonstrated promising results in managing tumor growth and increasing survival in preclinical models, suggesting its potential for improving treatment outcomes in lung cancer patients with BM.
Article Synopsis
- - Propranolol, a drug used for treating severe infantile hemangiomas (IH), has shown potential antitumor effects in some malignant tumors, but its mechanism of action remains unclear due to a lack of suitable tumor models.
- - Researchers created a responsive tumor model using immunodeficient mice and identified Aquaporin-1 (AQP1) as a key protein that mediates the tumor growth inhibition caused by propranolol.
- - Functional studies revealed that AQP1 is found in a specific layer of cells within IH and is crucial for the response to propranolol, suggesting that interactions between vascular cells and stromal telocytes enhance the drug's effectiveness.
Article Synopsis
- CRISPR/Cas9 is a gene-editing technology that, while effective, often causes unintended changes alongside precise edits, particularly issues like small insertions or deletions.
- Recent tests on mutation-specific guide RNAs aimed to correct dominant inherited diseases without affecting the normal allele, and this study expanded the approach to compound heterozygous recessive mutations.
- The research resulted in successful gene function restoration for a patient with congenital erythropoietic porphyria using mutant allele-specific guide RNAs, which showed less genotoxicity and potential for safer, targeted therapy compared to the traditional biallelic guides.
Approaches able to counteract, at least temporarily, hypoxia, a well-known factor of resistance to treatment in solid tumors are highly desirable. Herein, we report the use of nanosized zeolite crystals as hyperoxic/hypercapnic gas carriers for glioblastoma. First, the non-toxic profile of nanosized zeolite crystals in living animals (mice, rats and non-human primates) and in various cell types is presented.
View Article and Find Full Text PDFArticle Synopsis
- Tumor hypoxia reduces the effectiveness of radiation therapy, highlighted by the concept of oxygen enhancement ratio (OER), which is influenced by factors like pO and linear energy transfer (LET).
- Glioblastoma (GB) shows resistance to low-LET radiation (like X-rays) due to its hypoxic environment, prompting research into whether high-LET radiation, particularly carbon ion radiotherapy (CIRT), can counteract this resistance.
- The study evaluated the effects of CIRT on two human GB cell lines under varying LET conditions and found that while CIRT is generally more effective than X-rays, the presence of hypoxia continues to limit its effectiveness, with potential variations based on ERK activation and EPO signaling.
Article Synopsis
- Diacetyl-bis(N4-methylthiosemicarbazone) labeled with 64Cu (Cu-ATSM) has potential as a hypoxia imaging tracer, but previous studies have raised concerns about its reliability and tumor location impact.
- The study analyzed the uptake of Cu-ATSM and its less lipophilic counterpart Cu-Cl in an orthotopic glioblastoma model to assess their performance in different oxygen levels and correlate uptake with hypoxic markers.
- Results indicated that Cu-ATSM primarily accumulates in hypoxic tumor areas, but also in non-hypoxic regions due to high copper transporter expression, while Cu-Cl2 showed better retention at higher oxygen levels, suggesting varied behavior under different conditions.
Impact of Vaping Regimens on Electronic Cigarette Efficiency.
Int J Environ Res Public Health
November 2019
Most recent studies on electronic cigarettes (e-cigs) have been carried out using vaping regimens consistent with mouth-to-lung inhalation (MTL) and not with direct-to-lung (DTL) inhalation. This paper aimed to characterizing the influence of inhalation properties (puff duration, puff volume, airflow rate) on the mass of vaporized e-liquid (MVE). Because the literature on DTL is non-existent, an intense vaping regimen consistent with DTL inhalation (i.
View Article and Find Full Text PDFArticle Synopsis
- New preclinical image-guided irradiators and treatment planning systems have advanced radiobiology, but their quality control is lagging compared to clinical radiotherapy, especially for in vivo dosimetry.
- The study used a scintillating fiber dosimeter called DosiRat to compare planned versus actual doses in small animal irradiations, focusing on various irradiation conditions and specific dose measurements.
- Results showed that while discrepancies in planned versus measured doses were generally within a 5% accuracy range for phantom tests, variations for animal irradiations were larger, indicating challenges in implementing effective in vivo dosimetry with current technology.
Article Synopsis
- Brain metastases are common in breast cancer patients, leading to a short overall survival of around 6 months despite treatments like external beam radiotherapy (EBRT).
- This study explores a new targeted therapy using lead-212 (212Pb) combined with an anti-VCAM-1 antibody, which effectively targets the early stages of brain metastases.
- Results showed that 212Pb-αVCAM-1 significantly reduced tumor burden and improved overall survival by 29% compared to standard EBRT, without major toxicity observed.