RESUMEN

Preparation of Li4ZrF8:Ce3+ and Li4ZrF8:Ce3+,Gd3+ phosphors is described. Data on luminescence characteristics are presented. Hydrothermal route was employed for the synthesis. Li4ZrF8 crystallizes in orthorhombic system with Pnma space group. Li atoms are distributed over two sites, both having same coordination of six. Zr is also similarly distributed over two 8 coordinated sites. Li4ZrF8:Ce3+ emits a broad band UVB light, while the emission of Li4ZrF8:Ce3+,Gd3+ is in form of a narrow line around 311 nm attributed to 6P7/2 â†’ 8S7/2. Both phosphors exhibited a broad excitation spectrum with a peak at 253 nm. The excitation and emission properties are thus adequate enough to obtain UVB light sources using a conventional high pressure mercury vapour lamp or an ultraviolet LED.

RESUMEN

PURPOSE: To explore the optimal of kiloelectron voltage (keV) of virtual monoenergetic imaging (VMI) of dual-layer spectral-detector CT (DLCT) in detecting neuroendocrine tumor liver metastases (NETLM) and to investigate diagnostic performance of polyenergetic images (PEI), DLCT, and Gd-EOB-DTPA-enhanced MR. METHODS: Seventy-two patients with suspected NETLM who underwent DLCT and Gd-EOB-DTPA-enhanced MR were retrospectively enrolled. Tumor signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were compared between PEI and VMI at 40-140 keV. Two radiologists read the CT examinations with and without VMI separately in consensus. Two other radiologists read the Gd-EOB-DTPA-enhanced MR in consensus. The diagnostic performance was evaluated. Reference standard was histopathology, follow-up, and interpretation of all available imaging. RESULTS: The highest SNR and CNR were observed at VMI40keV, significantly higher than PEI in the arterial and venous phases (all P<0.01). A total of 477 lesions were identified (396 metastases, 81 benign lesions). Per-lesion AUC was 0.86, 0.91, and 0.97 (PEI, DLCT, and Gd-EOB-DTPA-enhanced MR, respectively). Sensitivity of PEI, DLCT, and Gd-EOB-DTPA-enhanced MRI were 0.76, 0.86, and 0.95, respectively. DLCT significantly improved sensitivity compared to PEI. MR had significantly higher sensitivity than DLCT and PEI. Subgroup analysis demonstrated that the difference in diagnostic performance was concentrated on lesions < 10 mm. CONCLUSION: The image quality of VMI40keV is higher than that of PEI. DLCT with VMI40keV provides better diagnostic sensitivity for NETLM detection than PEI. Gd-EOB-DTPA-enhanced MR yielded the best diagnostic performance for NETLM detection.

RESUMEN

BACKGROUND: Patients with delayed endolymphatic hydrops (DEH) often show caloric hypofunction and endolymphatic hydrops (ELH) on gadolinium (Gd) enhanced magnetic resonance imaging (MRI) of the inner ear. OBJECTIVES: We aimed to investigate the relationship between the ELH in vivo and caloric results in ipsilateral DEH. MATERIAL AND METHODS: Twelve patients with ipsilateral DEH were included, who underwent delayed MRI following intratympanic Gd application, pure-tone audiometry, caloric test, and video head impulse test (vHIT). RESULTS: For the affected ears, the overall prevalence of inner ear hydrops was 91.7%, including 75% in the cochlear and 50% in vestibular compartment. For the non-affected ears, the overall prevalence of inner ear hydrops was 25%, including 25% in cochlear and 16.7% in vestibular region. Caloric hypofunction was demonstrated in 75% of the affected ears. No pathologic vHIT were found. Caloric results were in agreement with the radiological evidence of inner ear hydrops on affected and non-affected ears in 9 cases. There was fair concordance between inner ear hydrops and canal paresis abnormality on the affected side. CONCLUSIONS AND SIGNIFICANCE: MRI provides auxiliary evidence of ELH in vivo in the ipsilateral DEH-affected ears. The association between morphological alterations and caloric hypofunction warrants further investigation.

RESUMEN

Bovine herpesvirus 1 (BoHV-1), a significant pathogen in the alpha-herpesvirus subfamily, primarily infects cattle and causes the upper respiratory disease known as infectious bovine rhinotracheitis (IBR). In silico studies evaluated the BoHV-1 D protein to be non-allergenic, non-toxic, and highly antigenic, highlighting its potential as an antigen for vaccine development. Therefore, this study aimed to evaluate the efficacy of a subunit vaccine using the ectodomain of glycoprotein D (gD34-380) as an antigen. The truncated gD was successfully cloned and expressed in both Escherichia coli (E. coli, termed EgD) and baculovirus (termed BgD) systems, with expected molecular weights of 65 kDa and 50 kDa, respectively. For the vaccine formulation, the gD proteins were used either alone or in combination with in-house inactivated BoHV-1. Vaccination of mice and bovines showed that baculovirus-expressed gD34-380 accelerated the antibody response. Moreover, the BgD-vaccinated group also showed significantly higher neutralizing antibody levels against BoHV-1 than the control group (p<0.0001). In conclusion, our study found that BgD from BoHV-1 can increase the immune response and enhance vaccine efficacy.

RESUMEN

The Gd-doped ZnO/SnO2 nanocomposites with various atomic percentages (0, 0.5, 0.8, and 1.2 at%) of gadolinium (coded as GdZS0, GdZS1, GdZS2, and GdZS3) was synthesis via the sol-gel method and explored for photodegradation against dye solutions exposing solar light irradiation. The synthesized nanocomposites were characterized employing the XRD, FTIR, FE-SEM, Raman spectroscopy, BET analysis and UV-Vis spectrophotometer. The FE-SEM results indicated that the formation of nanoparticles to nanoflowers covered with Gd ions was observed with an increased doping concentration of Gd. The optical bandgap was evaluated and found in the range of 3.21-3.27 eV for GdZS nanocomposites. The GdZS nano-photocatalysts were investigated against the degradation of different organic dyes and GdZS3 shows the highest degradation efficiencies of 99.3%, 98.3% and 99.4% towards MO, MB and RhB dyes, respectively at neutral pH in aqueous media. Before and after photodegradation. Biological oxygen demand and chemical oxygen demand tests to make estimations of mineralization. The investigations are very promising for the degradation process in rare earth doped metal oxide nanocomposites. A plausible photodegradation mechanism of synthesized nanocomposites under investigation has also been proposed.

RESUMEN

Background: The hepatic steatosis and fibrosis related to metabolic dysfunction-associated steatotic liver disease (MASLD) are important factors in the progression. The Multi echo three-dimensional (3D) Dixon sequence can obtain a single breath hold scan for a fat fraction map and an R2* map. The R2* value is usually used to evaluate iron deposition. Whether the change in R2* value is related to liver fibrosis after injection of gadolinium disulfide (Gd) should be noted. This study evaluates the value of enhanced magnetic relaxation time in the risk stratification of liver fibrosis by analyzing the changes in R2* before and after Gd enhancement, and explores the potential application of Multi echo 3D Dixon sequence in one-stop evaluation of MASLD. Methods: This retrospective study included 138 MASLD patients who underwent Gadolinum ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA) magnetic resonance imaging (MRI) examination in The First Affiliated Hospital of Chongqing Medical University from June 2020 to December 2021. Finally, 90 subjects were divided into moderate and high-risk fibrosis group and low-risk fibrosis group by two-step assessment of liver fibrosis. Multi-echo 3D chemical shift imaging sequence (Q-Dixon) sequences and gradient-echo T1WI (Vibe-Dixon) sequence were performed during the non-enhanced phase and hepatobiliary phase, respectively, and then the signal-intensity enhancement (SE) and magnetic relaxation-time enhancement (RE) values were calculated. The interobserver correlation coefficient was used to evaluate the consistency between observers. Univariate t-test was used to analyze the differences in RE and SE of liver fibrosis among different risk levels. Delong analysis was performed on receiver operating characteristic (ROC) curve to evaluate the difference in diagnostic efficacy between RE and SE in differentiating the risk level of liver fibrosis. Results: Among the 90 patients, 55 (61.1%) belonged to the low-risk group and 35 (38.9%) belonged to the medium-to-high-risk group. The average RE and SE values were 1.23±0.15 and 1.57±0.23 in the low-risk group and 0.99±0.09 and 1.38±0.21 in both the medium-to-high-risk group (P<0.01). The ROC curve showed that the area under the curve (AUC) value of RE was 0.922, with a corresponding optimal threshold of 0.713, sensitivity of 0.852, and specificity of 0.861. The AUC value of SE was 0.724, with a corresponding optimal threshold of 0.352, sensitivity of 0.519, and specificity of 0.833. The AUC difference between RE and SE for the predictive value of different risk assessments was 0.198, and the 95% confidence interval of the difference was 0.084-0.312. The Delong test showed that the difference was significant (P<0.01). Conclusions: Magnetic RE had high effectiveness for distinguishing between liver-fibrosis risk levels. The combination of the Q-Dixon sequence and Gd-EOB-DTPA has the potential of one-stop evaluation of MASLD.

RESUMEN

Natural killer (NK) cells have multifaceted roles within the complex tumor milieu. They are pivotal components of innate immunity and shape the dynamic landscape of tumor-immune cell interactions, and thus can be leveraged for use in therapeutic interventions. NK-based immunotherapies have had remarkable success in hematological malignancies, but these therapies are met with many challenges in solid tumors, including neuroblastoma (NB), a childhood tumor arising from the sympathetic nervous system. With a focus on NB, this review outlines the mechanisms employed by NK cells to recognize and eliminate malignant cells, delving into the dynamic relationship between ligand-receptor interactions, cytokines, and other molecules that facilitate the cross talk between NK and NB cells. We discuss the immunomodulatory functions of NK cells and the mechanisms that contribute to loss of this immunosurveillance in NB, with a focus on how this dynamic has been utilized in recent immunotherapy advancements for NB.

RESUMEN

The aim of this study was to synthesize a quinoline-based MRI contrast agent, Gd-DOTA-FAPI04, and assess its capacity for targeting fibroblast activation protein (FAP)-positive tumors in vivo. Gd-DOTA-FAPI04 was synthesized by attaching a 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) complex of gadolinium(III) to FAP inhibitor FAPI04. The longitudinal relaxation time (T1) of the contrast agent was measured using a Siemens Prisma 3.0T MR system, and the CCK-8 assay was performed to evaluate its potential cytotoxicity. Male nude mice bearing tumors grown from FAP-expressing fibrosarcoma cells were divided into experimental (n = 4) and control (n = 4) groups, and T1-weighted image enhancement was measured at different times (0, 10, 30, 60, 90, and 120 min) postinjection of Gd-DOTA-FAPI04. The control group received an additional preinjection of excess FAPI04. FAP expression in tumor tissue was investigated by using immunohistochemistry with an anti-FAP antibody. The longitudinal relaxivities of gadodiamide and Gd-DOTA-FAPI04 were measured to be 3.734 mM-1 s-1 and 5.323 mM-1 s-1, respectively. The CCK-8 assay demonstrated that Gd-DOTA-FAPI04 has minimal toxicity to cultured human fibrosarcoma cells. In vivo MRI showed that peak accumulation of Gd-DOTA-FAPI04 in FAP-expressing tumors occurred 1 h postinjection and could be blocked by preinjection of excess FAPI04. Immunohistochemical analysis of harvested tumor tissue supported the above findings. Gd-DOTA-FAPI04 is a promising contrast agent for in vivo imaging of FAP.

RESUMEN

Hereditary spastic paraplegia (HSP) is a heterogeneous group of neurological disorders that are characterized by progressive spasticity and weakness in the lower limbs. SPG26 is a complicated form of HSP, which includes not only weakness in the lower limbs, but also cognitive impairment, developmental delay, cerebellar ataxia, dysarthria, and peripheral neuropathy, and is caused by biallelic mutations in the B4GALNT1 (beta-1,4-N-acetylgalactosaminyltransferase 1) gene. The B4GALNT1 gene encodes ganglioside GM2/GD2 synthase (GM2S), which catalyzes the transfer of N-acetylgalactosamine to lactosylceramide, GM3, and GD3 to generate GA2, GM2, and GD2, respectively. The present study attempted to characterize a novel B4GALNT1 variant (NM_001478.5:c.937G>A p.Asp313Asn) detected in a patient with progressive multi-system neurodegeneration as well as deleterious variants found in the general population in Japan. Peripheral blood T cells from our patient lacked the ability for activation-induced ganglioside expression assessed by cell surface cholera toxin binding. Structural predictions suggested that the amino acid substitution, p.Asp313Asn, impaired binding to the donor substrate UDP-GalNAc. An in vitro enzyme assay demonstrated that the variant protein did not exhibit GM2S activity, leading to the diagnosis of HSP26. This is the first case diagnosed with SPG26 in Japan. We then extracted 10 novel missense variants of B4GALNT1 from the whole-genome reference panel jMorp (8.3KJPN) of the Tohoku medical megabank organization, which were predicted to be deleterious by Polyphen-2 and SIFT programs. We performed a functional evaluation of these variants and demonstrated that many showed perturbed subcellular localization. Five of these variants exhibited no or significantly decreased GM2S activity with less than 10% activity of the wild-type protein, indicating that they are carrier variants for HSP26. These results provide the basis for molecular analyses of B4GALNT1 variants present in the Japanese population and will help improve the molecular diagnosis of patients suspected of having HSP.

RESUMEN

Background: There is still no consensus about the coronavirus disease 2019 (COVID-19) vaccine-associated glomerular disease (CVAGD). Given the large number of vaccinations administered and the variations in glomerulopathy observed across different countries and regional environments, CVAGD remains an important area of concern. Aim of study: We aimed to elucidate the findings of CVAGD within a Taiwanese cohort using biopsy data. Additionally, we endeavored to clarify the presentation of CVAGD. Methods: We collected data from patients who underwent renal biopsy from June 2021 to October 2022 at Taichung Veterans General Hospital. Two independent nephrologists meticulously reviewed the charts to exclude cases unrelated to vaccination. Results: Initially, a total of 286 patients underwent renal biopsy at our institute. Ultimately, we identified 14 patients with highly suspected CVAGD. All 14 patients exhibited proteinuria and hematuria. The urinary protein-to-creatinine ratio was elevated (median of 2012.1 mg/g; interquartile range (IQR) 25%-IQR 75%: 941.85-3884.1 mg/g) with a median serum creatinine level of 1.71 mg/dL (0.79-5.35). The majority of CVAGD cases were diagnosed as immunoglobulin A (IgA) nephropathy (n = 5, 35.7%), followed by antineutrophil cytoplasmic antibody (ANCA)-related rapidly progressive glomerulonephritis (RPGN) (n = 4, 28.6%). There were only three cases of minimal change disease each: one case of focal segmental glomerulosclerosis, one of membranous glomerulonephritis, and one of lupus nephritis. The culprit of COVID-19 vaccinations was 35.7% (n = 5) of Oxford-AstraZeneca (ChAdOx1-S), 42.9% (n = 6) of Moderna, and 21.4% (n = 3) of BNT162b2. Most patients experienced improvements in renal function. Only two cases of P-ANCA RPGN and one case of IgA nephropathy did not recover. Eighty percent of IgA nephropathy cases had favorable outcomes, but none of the patients with P-ANCA RPGN achieved full recovery. Conclusions: IgA nephropathy and ANCA-related RPGN were the most common CVAGD, and all types of COVID-19 vaccines posed a risk for CVAGD. However, further studies are required to confirm causality.

RESUMEN

Ganglioside GM3 synthase is a key enzyme involved in the biosynthesis of gangliosides. GM3 synthase deficiency (GM3SD) causes an absence of GM3 and all downstream biosynthetic derivatives, including all the a-, b-, c-series gangliosides, commonly found in neural tissues. The affected individuals manifest with severe irritability, intractable seizures, hearing loss, blindness, and profound intellectual disability. It has been reported that oral ganglioside supplementation has achieved some significant improvements in clinical symptoms, growth parameters, and developmental and cognitive scores in GM3SD patients. To gain insight into the molecular mechanisms of this supplementation, we performed supplementation of oral bovine milk gangliosides to GM3 synthase-deficient mice from early weaning periods. The oral milk ganglioside preparations were dominated by GM3 and GD3 gangliosides. Oral milk ganglioside supplementation improved the decreased cognitive function observed in GM3 synthase-deficient mice. The improvement in cognitive function was accompanied by increased ganglioside levels and neurogenesis in the hippocampus in the supplemented animals.

RESUMEN

This study uses magnetic resonance imaging (MRI) to investigate the potential of the hepatospecific contrast agent gadolinium ethoxybenzyl-diethylenetriaminepentaacetic acid (Gd-EOB-DTPA) in distinguishing G1- from G2/G3-differentiated hepatocellular carcinoma (HCC). Our approach involved analyzing the dynamic behavior of the contrast agent in different phases of imaging by signal intensity (SI) and lesion contrast (C), to surrounding liver parenchyma, and comparing it across distinct groups of patients differentiated based on the histopathological grading of their HCC lesions and the presence of liver cirrhosis. Our results highlighted a significant contrast between well- and poorly-differentiated lesions regarding the lesion contrast in the arterial and late arterial phases. Furthermore, the hepatobiliary phase showed limited diagnostic value in cirrhotic liver parenchyma due to altered pharmacokinetics. Ultimately, our findings underscore the potential of Gd-EOB-DTPA-enhanced MRI as a tool for improving preoperative diagnosis and treatment selection for HCC while emphasizing the need for continued research to overcome the diagnostic complexities posed by the disease.

RESUMEN

Type 1 Gaucher disease (GD1) is a rare, autosomal recessive disorder caused by glucocerebrosidase deficiency. Skeletal manifestations represent one of the most debilitating and potentially irreversible complications of GD1. Although imaging studies are the gold standard, early diagnostic/prognostic tools, such as molecular biomarkers, are needed for the rapid management of skeletal complications. This study aimed to identify potential protein biomarkers capable of predicting the early diagnosis of bone skeletal complications in GD1 patients using artificial intelligence. An in silico study was performed using the novel Therapeutic Performance Mapping System methodology to construct mathematical models of GD1-associated complications at the protein level. Pathophysiological characterization was performed before modeling, and a data science strategy was applied to the predicted protein activity for each protein in the models to identify classifiers. Statistical criteria were used to prioritize the most promising candidates, and 18 candidates were identified. Among them, PDGFB, IL1R2, PTH and CCL3 (MIP-1α) were highlighted due to their ease of measurement in blood. This study proposes a validated novel tool to discover new protein biomarkers to support clinician decision-making in an area where medical needs have not yet been met. However, confirming the results using in vitro and/or in vivo studies is necessary.

Asunto(s)

RESUMEN

The use of the rare earth element gadolinium (Gd) in contrast agents for magnetic resonance imaging has led to a significant (micro-)contamination of riverine and coastal environments in many parts of the world. This study comprises a detailed investigation on the rare earth elements and yttrium inventory of the North Sea and also reports data for the major tributaries Thames, Rhine, Ems, Weser and Elbe. We show that large parts of the southern North Sea, including the Wadden Sea UNESCO Natural World Heritage site, are (micro)contaminated with Gd from Gd-based contrast agents (GBCA). Their dispersion reveals their estuarine input and allows to effectively track water masses and currents. The chemical persistence and conservative behavior of GBCA, coupled with the low detection limits of state-of-the-art analytical methods, makes the anthropogenic Gd a sensitive screening proxy for monitoring similarly stable, but potentially hazardous, persistent chemical/pharmaceutical substances in natural waters.

Asunto(s)

RESUMEN

A novel method for synthesizing dumbbell-shaped (Gd1-xTbx)2O(CO3)2·H2O (GOC:xTb3+) phosphors using sodium carbonate was investigated. An amount of 1 mmol of stable fluorescent powder can be widely prepared using 3-11 mmol of Na2CO3 at a pH value of 8.5-10.5 in the reaction solution. The optimal reaction conditions for the phosphors were determined to be 7 mmol for the amount of sodium carbonate and a pH of 9.5 in the solution. Mapping analysis of the elements confirmed uniform distribution of Gd3+ and Tb3+ elements in GOC:xTb3+. The analysis of fluorescence intensity shows that an optimal excitation wavelength of 273 nm is observed when the concentration of Tb3+ is between 0.005 and 0.3. The highest emission intensity was observed for GOC:0.05Tb3+ with a 57.5% maximum quantum efficiency. The chromaticity coordinates show that the color of GOC:Tb3+ is stable and suitable for fluorescence recognition. Latent fingerprint visualization reveals distinctive features like whorls, hooks, and bifurcations. Therefore, the sodium carbonate method offers an effective alternative to traditional urea chemical reaction conditions for preparing GOC:Tb3+.

RESUMEN

PURPOSE: This study aims to investigate the effect of Niraparib in combination with an Anti-GD2 Antibody on osteosarcoma cells. METHODS: Scratch test was utilized to assess cell migration capacity, while the Transwell experiment was utilized to evaluate cell invasion potential. Cell proliferation was measured using the CCK8 experiment. The affinity between the anti-GD2 antibody and its antigen was determined via ELISA. Tumor growth was evaluated through animal experiments. Western blotting, QRT-PCR, and histological analysis were conducted to examine the expression of relevant proteins and mRNAs. RESULTS: MG63 cell line was used for an example. The scratch test showed that the migration rate of osteosarcoma cells in Niraparib + Anti-GD2 group was 1.07 ± 0.04 after 48 h, and 0.34 ± 0.04 in the Control group. Transwell experiment showed that the invasion ability of osteosarcoma cells in Niraparib + Anti-GD2 group was 21.0 ± 1.5, and that in Control group was 87.7 ± 2.9. CCK8 experiment showed that the absorbance value of Niraparib + Anti-GD2 group was 0.16 ± 0.10 on day 5, and that of the Control group was 0.76 ± 0.09. Western blotting showed that the expression levels of BALP and CICP in Niraparib + Anti-GD2 group were 0.751 ± 0.135 and 1.086 ± 0.115, respectively, and those in Control group were 1.025 ± 0.143 and 1.216 ± 0.168, respectively. QRT-PCR results showed that the absorbance values of Niraparib + Anti-GD2 group were 0.173 ± 0.065 and 0.170 ± 0.078 on day 14. The results of animal experiments showed that on day 5, the tumor volume of the Control group was 2433 ± 391, and that of the Niraparib + Anti-GD2 group was 1137 ± 148. Histological analysis showed that the mean density values of Niraparib + Anti-GD2 group were 0.19 ± 0.08 and 0.22 ± 0.07, and those of Control group were 0.26 ± 0.09 and 0.29 ± 0.10. CONCLUSION: The combination of Niraparib and Anti-GD2 antibody significantly inhibits Osteosarcoma cells.

RESUMEN

In this study, we developed new gadolinium-graphene quantum dot nanoparticles (Gd-GQDs) as a theranostic platform for magnetic resonance imaging and improved the efficiency of radiotherapy in HPV-positive oropharyngeal cancer. Based on cell toxicity results, Gd-GQD NPs were nontoxic for both cancer and normal cell lines up to 25 µg/ml. These NPs enhance the cytotoxic effect of radiation only on cancer cells but not on normal cells. The flow cytometry analysis indicated that cell death mainly occurred in the late phase of apoptosis. The immunocytochemical analysis was used to evaluate apoptosis pathway proteins. The Bcl-2 and p53 protein levels did not differ statistically significantly between radiation alone group and those that received irradiation in combination with NPs. In contrast, the combination group exhibited a significant increase in Bax protein expression, suggesting that cells could undergo apoptosis independent of the p53 pathway. Magnetic resonance (MR) imaging showed that Gd-GQD NPs, when used at low concentrations, enhanced T1-weighted signal intensity resulting from T1 shortening effects. At higher concentrations, the T2 shortening effect became predominant and was able to decrease the signal intensity. Gd-GQD appears to offer a novel approach for enhancing the effectiveness of radiation treatment and facilitating MR imaging for monitoring HPV-positive tumors.

Asunto(s)

RESUMEN

A custom Monte Carlo (MC) computer model was developed to simulate thermal neutron absorption in, and subsequent photon and electron emission from, natural Gd with a view to using the material as a neutron conversion layer for neutron detectors. The MC code also modelled photon and electron detection with two dissimilar detectors: a thick (500 µm) single crystal diamond detector; and a thin (5.15 µm) commercial off the shelf (COTS) 4H-SiC photodiode detector. The detectors' quantum detection efficiencies (QE) for hard X-rays and γ-rays were relatively low in comparison to their QE for electrons, thus making it possible to collect electron spectra from the Gd layer neutron conversion products which were not overwhelmed by photon emissions from the Gd. The MC code was utilised to determine the optimal thickness of Gd for the efficient detection of a thermal neutron flux. These radiation hard and spectroscopic detectors paired with natural Gd could find utility as robust and compact thermal neutron detectors for nuclear science and engineering, space science, and other applications.

RESUMEN

The immune system plays an important role in fracture healing, by modulating the pro-inflammatory and anti-inflammatory responses occurring instantly upon injury. An imbalance in these responses can lead to adverse outcomes, such as non-union of fractures. Implants are used to support and stabilize complex fractures. Biodegradable metallic implants offer the potential to avoid a second surgery for implant removal, unlike non-degradable implants. However, considering our dynamic immune system it is important to conduct in-depth studies on the immune response to these implants in living systems. In this study, we investigated the immune response to Mg and Mg-10Gd in vivo in a rat femur fracture model with external fixation. In vivo imaging using liposomal formulations was used to monitor the fluorescence-related inflammation over time. We combine ex vivo methods with our in vivo study to evaluate and understand the systemic and local effects of the implants on the immune response. We observed no significant local or systemic effects in the Mg-10Gd implanted group compared to the SHAM and Mg implanted groups over time. Our findings suggest that Mg-10Gd is a more compatible implant material than Mg, with no adverse effects observed in the early phase of fracture healing during our 4-week study. STATEMENT OF SIGNIFICANCE: Degradable metallic implants in form of Mg and Mg-10Gd intramedullary pins were assessed in a rat femur fracture model, alongside a non-implanted SHAM group with special respect to the potential to induce an inflammatory response. This pre-clinical study combines innovative non-invasive in vivo imaging techniques associated with multimodal, ex vivo cellular and molecular analytics. The study contributes to the development and evaluation of degradable biometals and their clinical application potential. The study results indicate that Mg-10Gd did not exhibit any significant harmful effects compared to the SHAM and Mg groups.

Asunto(s)

RESUMEN

Society's interest in rare earth elements (REEs) and their increasing use in many fields is leading to enrichments in aquatic environments, such as estuaries. This study of the Seine estuary assessed the distribution of REEs along the food web, including different species from 5 phyla representing different trophic levels. Total REE concentrations, which were higher in algae, mollusks, crustaceans and annelids (4.85-156; 1.59-4.08; 2.48 ± 1.80 and 0.14 ± 0.11 µg/g dw, respectively) than in vertebrates (0.03-0.15 µg/g dw), correlated with δ15N indicated a trophic dilution. REE contributions in the studied species were higher for light REEs than for heavy and medium REEs. Positives anomalies for Eu, Gd, Tb and Lu were highlighted particularly in vertebrates, possibly due to species-dependent bioaccumulation/detoxification or related to anthropogenic inputs. The calculated BAF and BSAF indicated an important partitioning of REEs in organisms compared to the dissolved phase and a limited transfer from sediment to organisms.

Asunto(s)