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1.
Heliyon ; 10(7): e27362, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38560168

RESUMO

Background: Primary liver cancer (PLC) is a prevalent malignancy of the digestive system characterized by insidious symptom onset and a generally poor prognosis. Recent studies have highlighted a significant correlation between the initiation and prognosis of liver cancer and the immune function of PLC patients. Purpose: Revealing the expression of PLC-related immune genes and the characteristics of immune cell infiltration provides assistance for the analysis of clinical pathological parameters and prognosis of PLC patients. Methods: PLC-related differentially expressed genes (DEGs) with a median absolute deviation (MAD > 0.5) were identified from TCGA and GEO databases. These DEGs were intersected with immune-related genes (IRGs) from the ImmPort database to obtain PLC-related IRGs. The method of constructing a prognostic model through immune-related gene pairs (IRGPs) is used to obtain IRGPs and conduct the selection of central immune genes. The central immune genes obtained from the selection of IRGPs are validated in PLC. Subsequently, the relative proportions of 22 types of immune cells in different immune risk groups are evaluated, and the differential characteristics of PLC-related immune cells are verified through animal experiments. Results: Through database screening and the construction of an IRGP prognosis model, 84 pairs of IRGPs (P < 0.001) were ultimately obtained. Analysis of these 84 IRGPs revealed 11 central immune genes related to PLC, showing differential expression in liver cancer tissues compared to normal liver tissues. Results from the CiberSort platform indicate differential expression of immune cells such as naive B cells, macrophages, and neutrophils in different immune risk groups. Animal experiments demonstrated altered immune cell proportions in H22 tumor-bearing mice, validating findings from peripheral blood and spleen homogenate analyses. Conclusion: Our study successfully predicted and validated PLC-related IRGs and immune cells, suggesting their potential as prognostic indicators and therapeutic targets for PLC.

2.
Eur J Immunol ; : e2350761, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566526

RESUMO

In multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis (EAE), early pathological features include immune cell infiltration into the central nervous system (CNS) and blood-brain barrier (BBB) disruption. We investigated the role of junctional adhesion molecule-A (JAM-A), a tight junction protein, in active EAE (aEAE) pathogenesis. Our study confirms JAM-A expression at the blood-brain barrier and its luminal redistribution during aEAE. JAM-A deficient (JAM-A-/-) C57BL/6J mice exhibited milder aEAE, unrelated to myelin oligodendrocyte glycoprotein-specific CD4+ T-cell priming. While JAM-A absence influenced macrophage behavior on primary mouse brain microvascular endothelial cells (pMBMECs) under flow in vitro, it did not impact T-cell extravasation across primary mouse brain microvascular endothelial cells. At aEAE onset, we observed reduced lymphocyte and CCR2+ macrophage infiltration into the spinal cord of JAM-A-/- mice compared to control littermates. This correlated with increased CD3+ T-cell accumulation in spinal cord perivascular spaces and brain leptomeninges, suggesting JAM-A absence leads to T-cell trapping in central nervous system border compartments. In summary, JAM-A plays a role in immune cell infiltration and clinical disease progression in aEAE.

3.
Nervenarzt ; 2024 Apr 03.
Artigo em Alemão | MEDLINE | ID: mdl-38568318

RESUMO

Treatment-resistant depression (TRD) is a complex disorder. Although no standardized definition has been established to date, there are promising and well-established treatment options for the condition. Looking at the current pharmacological and neuromodulatory strategies, there is an urgent need for fast-acting and well-tolerated treatment options. The search for new mechanisms of action goes beyond the monoamine hypothesis. For example, esketamine is already an established treatment method that is fast-acting and well tolerated, while psychedelics or esmethadone are currently still undergoing clinical trials. Compounds that can be used off-label, such as dextromethorphan or anti-inflammatory strategies are also presented. Pharmacological approaches that focus on the modulation of the glutamatergic system or belong to the class of psychedelics, appear to be of particular importance for current research and development. These particularly include substances that rapidly exert clinical effects and have a favorable side-effect profile.

4.
J Vet Pharmacol Ther ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557931

RESUMO

Lameness is a significant welfare concern in goats. Amphotericin B is used via intraarticular (IA) administration in models to study experimentally induced lameness in large animals. The main objective of this study was to estimate plasma pharmacokinetic (PK) parameters for amphotericin B in goats after a single IA administration. Liposomal amphotericin B was administered to ten Kiko-cross goats at a dose of 10 mg total (range: 0.34-0.51 mg/kg) via IA administration into the right hind lateral distal interphalangeal joint. Plasma samples were collected over 96 h. Amphotericin B concentrations were measured via liquid chromatography/mass spectrometry (LC-MS/MS). A non-compartmental analysis was used to derive PK parameters. Following single IA administration, maximum plasma concentration was estimated at 54.6 ± 16.5 ng/mL, and time to maximum concentration ranged from 6 to 12 h. Elimination half-life was estimated at 30.9 ± 16.5 h, and mean residence time was 45.1 ± 10.4 h. The volume of distribution after IA administration was 13.3 ± 9.4 L/kg. The area under the curve was 1481 ± 761 h*ng/mL. The achieved maximum concentration was less than the observed concentrations for other species and routes of administration. Further research is needed into the pharmacodynamics of IA liposomal amphotericin B in goats to determine specific research strategies.

5.
Ann Biomed Eng ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38558355

RESUMO

The vibrational characteristics of the Hybrid III and NOCSAE headforms are not well understood. It is hypothesized that they may perform differently in certain loading environments due to their structural differences; their frequency responses may differ depending on the impact characteristics. Short-duration impacts excite a wider range of headform frequencies than longer-duration (padded) impacts. While headforms generally perform similarly during padded head impacts where resonant frequencies are avoided, excitation of resonant frequencies during short-duration impacts can result in differences in kinematic measurements between headforms for the matched impacts. This study aimed to identify the natural frequencies of each headform through experimental modal analysis techniques. An impulse hammer was used to excite various locations on both the Hybrid III and NOCSAE headforms. The resulting frequency response functions were analyzed to determine the first natural frequencies. The average first natural frequency of the NOCSAE headform was 812 Hz. The Hybrid III headform did not exhibit any natural frequencies below 1000 Hz. Comparisons of our results with previous studies of the human head suggest that the NOCSAE headform's vibrational response aligns more closely with that of the human head, as it exhibits lower natural frequencies. This insight is particularly relevant for assessing head injury risk in short-duration impact scenarios, where resonant frequencies can influence the injury outcome.

6.
Curr Pharm Des ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38561613

RESUMO

BACKGROUND: Spinal Muscular Atrophy (SMA) is a severe motor neuronal disorder with high morbidity and mortality. Securinine has shown the potential to treat SMA; however, its anti-SMA role remains unclear. OBJECTIVE: This study aims to reveal the anti-SMA mechanisms of securinine. METHODS: Securinine-associated targets were acquired from Herbal Ingredients' Targets (HIT), Similarity Ensemble Approach (SEA), and SuperPred. SMA-associated targets were obtained from GeneCards and Dis- GeNET. Protein-protein interaction (PPI) network was constructed using GeneMANIA, and hug targets were screened using cytoHubba. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed using ClusterProfifiler. Molecular docking was conducted using Pymol and Auto- Dock. In vitro assays were used to verify the anti-SMA effects of securinine. RESULTS: Twenty-six intersection targets of securinine and SMA were obtained. HDAC1, HDAC2, TOP2A, PIK3R1, PRMT5, JAK2, HSP90AB1, TERT, PTGS2, and PAX8 were the core targets in PPI network. GO analysis demonstrated that the intersecting targets were implicated in the regulation of proteins, steroid hormones, histone deacetylases, and DNA transcription. KEGG analysis, pathway-pathway, and hub target-pathway networks revealed that securinine might treat SMA through TNF, JAK-STAT, Ras, and PI3K-Akt pathways. Securinine had a favorable binding affinity with HDAC1, HSP90AB, JAK2, PRMT5, PTGS2, and TERT. Securinine rescued viability suppression, mitochondria damage, and SMN loss in the SMA cell model. Furthermore, securinine increased HDAC1 and PRMT5 expression, decreased PTGS2 expression, suppressed the JAK2-STAT3 pathway, and promoted the PI3K-Akt pathway. CONCLUSION: Securinine might alleviate SMA by elevating HDAC1 and PRMT5 expression and reducing PTGS2 via JAK2-STAT3 suppression and PI3K-Akt activation.

7.
APMIS ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563150

RESUMO

Multiple sclerosis (MS) is a condition where the central nervous system loses its myelin coating due to autoimmune inflammation. The experimental autoimmune encephalomyelitis (EAE) simulates some aspects of human MS. Boswellic acids are natural compounds derived from frankincense extract, known for their anti-inflammatory properties. The purpose of this research was to investigate therapeutic potential of boswellic acids. Mice were divided into three groups: low-dose (LD), high-dose (HD), and control groups (CTRL). Following EAE induction, the mice received daily doses of boswellic acid for 25 days. Brain tissue damage, clinical symptoms, and levels of TGF-ß, IFN-γ, and IL-17 cytokines in cell cultured supernatant of lymphocytes were assessed. Gene expression of transcription factors in brain was measured using real-time PCR. The levels of brain demyelination were significantly lower in the treatment groups compared to the CTRL group. Boswellic acid reduced the severity and duration of EAE symptoms. Furthermore, boswellic acid decreased the amounts of IFN-γ and IL-17, also the expression of T-bet and ROR-γt in brain. On the contrary, it increased the levels of TGF-ß and the expression FoxP3 and GATA3. Our findings suggest that boswellic acids possess therapeutic potential for EAE by modulating the immune response and reducing inflammation.

8.
BMC Bioinformatics ; 25(1): 143, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566033

RESUMO

BACKGROUND: Liquid-liquid phase separation (LLPS) by biomolecules plays a central role in various biological phenomena and has garnered significant attention. The behavior of LLPS is strongly influenced by the characteristics of RNAs and environmental factors such as pH and temperature, as well as the properties of proteins. Recently, several databases recording LLPS-related biomolecules have been established, and prediction models of LLPS-related phenomena have been explored using these databases. However, a prediction model that concurrently considers proteins, RNAs, and experimental conditions has not been developed due to the limited information available from individual experiments in public databases. RESULTS: To address this challenge, we have constructed a new dataset, RNAPSEC, which serves each experiment as a data point. This dataset was accomplished by manually collecting data from public literature. Utilizing RNAPSEC, we developed two prediction models that consider a protein, RNA, and experimental conditions. The first model can predict the LLPS behavior of a protein and RNA under given experimental conditions. The second model can predict the required conditions for a given protein and RNA to undergo LLPS. CONCLUSIONS: RNAPSEC and these prediction models are expected to accelerate our understanding of the roles of proteins, RNAs, and environmental factors in LLPS.


Assuntos
Proteínas Intrinsicamente Desordenadas , RNA , RNA/genética , Proteínas Intrinsicamente Desordenadas/química
9.
Heliyon ; 10(7): e28091, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38571659

RESUMO

Background: Colorectal cancer (CRC) is one of the most common malignancies, and pyroptosis exerts an immunoregulatory role in CRC. Although the location of the primary tumor is a prognostic factor for patients with CRC, the mechanisms of pyroptosis in left- and right-sided CRC remain unclear. Methods: Expression and clinical data were collected from The Cancer Genome Atlas and Gene Expression Omnibus databases. Differences in clinical characteristics, immune cell infiltration, and somatic mutations between left- and right-sided CRC were then compared. After screening for differentially expressed genes, Pearson correlation analysis was performed to select pyroptosis-related genes, followed by a gene set enrichment analysis. Univariate and multivariate Cox regression analyses were used to construct and validate the prognostic model and nomogram for predicting prognosis. Collected left- and right-sided CRC samples were subjected to reverse transcription-quantitative polymerase chain reaction (RT-qPCR) to validate the expression of key pyroptosis-related genes. Results: Left- and right-sided CRC exhibited significant differences in clinical features and immune cell infiltration. Five prognostic signatures were identified from among 134 pyroptosis-related differentially expressed genes to construct a risk score-based prognostic model, and adverse outcomes for high-risk patients were further verified using an external cohort. A nomogram was also generated based on three independent prognostic factors to predict survival probabilities, while calibration curves confirmed the consistency between the predicted and actual survival. Experiment data confirmed the significant differential expression of five genes between left- and right-sided CRC. Conclusion: The five identified pyroptosis-related gene signatures may be potential biomarkers for predicting prognosis in left- and right-sided CRC and may help improve the clinical outcomes of patients with CRC.

10.
Crohns Colitis 360 ; 6(2): otae019, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38595967

RESUMO

Background: A better understanding of motivations to participate as well as recommendations to reduce barriers to enrollment may assist in design of future clinical trials. Methods: We developed a 32-item electronic questionnaire to explore motivations, experiences, and recommendations of inflammatory bowel disease patients, who had participated in pharmaceutical clinical trials in a tertiary center in Canada over the last decade. We employed a mixed-methods approach that integrates both quantitative and qualitative research methods. Results: We distributed a total of 69 e-mails with surveys and received 46 responses (66.6% response rate). Study participants were mostly male (27/46, 58.7%), non-Hispanic White (43/46, 93.5%), with a mean age of 45.5 years (SD 10.9). Most decided to participate in a clinical trial to benefit future patients (29/46, 63.0%). Half of the participants (23/46, 50.0%) reported they were worried about the possibility of receiving placebo, although the majority (29/46, 63.0%) understood they could improve on placebo. The most challenging aspect reported was the number and length of questionnaires (15/46, 32.6%), as well as the number of colonoscopies (14/46, 30.4%). Strategies recommended to increase enrollment were reduction of the chance of receiving placebo (20/46, 43.5%), facilitating inclusion of patients who have failed multiple therapies (20/46, 43.5%), allowing virtual visits (18/46, 39.1%), including subtypes of disease traditionally excluded from trials (16/46, 34.8%) and improving outreach to underrepresented populations (13/46, 28.3%). The vast majority (37/46, 80.4%) reported their experience of participation to be better than expected. Conclusions: These results should help inform the design of future clinical trials with a focus on patient-centricity.

11.
Heliyon ; 10(7): e28380, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38596023

RESUMO

This work aimed at investigating blends of Khaya senegalensis biodiesel in a compression ignition engine, attempting to improve engine performance and reduce CO2 emission compared with conventional diesel. Analysis of System (ANSYS) was used to predict in-cylinder behavior of the fuel. ANSYS SpaceClaim generated the geometric model on which 5° sector and mesh refinement was on ANSYS Internal Combustion Engine Modeler (ICEM). Computational domain of interest lies within the compression and expansion strokes. Experimental validation followed: 5% biodiesel, 95% diesel (B5); 15% biodiesel, 85% diesel (B15); 25% biodiesel, 75% diesel (B25); pure diesel (D100); pure biodiesel (B100) in volume proportions. B15 has the highest brake mean effective pressure (BMEP) of 4 bar as load increases. An experimental and numerical comparison reveals pressure declination against speed increment. Ignition temperature fluctuated between 799.76 and 806.256 K for D100 and 760.73-790.62 K for B100 within 1800-2800 rpm speed limit prediction. Power and brake thermal efficiency (BTE) had parallel load increment with all blends. CO2 emission on increasing load conditions were 47.01%, 8.07%, 21.72% and 6.06% for B5, B15, B25, and B100 respectively lower than D100. Pressure and temperature contours gave proper combustion predicted behaviors. All blends possess replaceable performance potential for D100 however, B5 offers better reliable potentials.

12.
J Appl Crystallogr ; 57(Pt 2): 529-538, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38596720

RESUMO

Data collection at X-ray free electron lasers has particular experimental challenges, such as continuous sample delivery or the use of novel ultrafast high-dynamic-range gain-switching X-ray detectors. This can result in a multitude of data artefacts, which can be detrimental to accurately determining structure-factor amplitudes for serial crystallography or single-particle imaging experiments. Here, a new data-classification tool is reported that offers a variety of machine-learning algorithms to sort data trained either on manual data sorting by the user or by profile fitting the intensity distribution on the detector based on the experiment. This is integrated into an easy-to-use graphical user interface, specifically designed to support the detectors, file formats and software available at most X-ray free electron laser facilities. The highly modular design makes the tool easily expandable to comply with other X-ray sources and detectors, and the supervised learning approach enables even the novice user to sort data containing unwanted artefacts or perform routine data-analysis tasks such as hit finding during an experiment, without needing to write code.

13.
J Vasc Interv Radiol ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38599280

RESUMO

PURPOSE: To evaluate the performance of a prototype flexible transbronchial cryoprobe compared to percutaneous transthoracic cryoablation and to define cone-beam CT (CBCT) imaging and pathology cryolesion features in an in vivo swine model. METHODS: Transbronchial cryoablation was performed with a prototype flexible cryoprobe (3 central and 3 peripheral lung ablations in 3 swine) and compared to transthoracic cryoablation performed with a commercially available rigid cryoprobe (2 peripheral lung ablations in 1 swine). Procedural time and cryoablation success rates for endobronchial navigation and cryoneedle deployment were measured. Intraoperative CBCT imaging features of cryolesions were characterized and correlated with gross and H&E-stained sections of the explanted cryolesions. RESULTS: The flexible cryoprobe was successfully navigated and delivered to each target through a steerable guiding sheath (6/6). At 4 min post ablation, 5/6 transbronchial and 2/2 transthoracic cryolesions were visible on CBCT. The volumes on CBCT images were 55.5±8.0 cm3 for central transbronchial ablations (n=2), 72.5±8.1 cm3 for peripheral transbronchial ablations (n=3), and 79.5±11.6 cm3 for peripheral transthoracic ablations (n=2). Pneumothorax developed in one animal post transbronchial ablation and during ablation in the transthoracic cryoablation. Images of cryoablation zones on CBCT correlated well with the matched gross and histopathology sections of the cryolesions. CONCLUSIONS: Transbronchial cryoablation with a flexible cryoprobe, delivered through a steerable guiding sheath, is feasible. Transbronchial cryoablation zones are imageable with CBCT with gross and histopathology similar to transthoracic cryoablation.

14.
Heliyon ; 10(7): e28996, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38601532

RESUMO

Generally, the monostrand anchor, which is made of cast iron and used in the global market, has a rectangular shape. It is commonly used when low concrete stresses are induced and minimum slab thickness is needed. Multiple monostrand anchors can be used adjacent to each other at one or more horizontal levels in slabs to replace a multistrand anchor system, which combines two or more strands in the same anchor. Monostrand anchor has a proper stress distribution, while the multistrand has greater overlap zone stresses in post tension slabs. An experimental study was conducted on round monostrand anchors to investigate anchorage and anchor bearing zones. Concrete blocks were prepared, and tested at different ages. The goal is to evaluate the contribution of the concrete's strength improvement against bursting pressure caused by jacking forces at the edge zone of a flat slab. The blocks were stressed using jacking machine. Strands with two diameter sizes (12.7 mm and 15.7 mm) were used. A rigid steel framework was developed as an abutment that can withstand all jack's response forces on the tested concrete blocks. On the other hand, this framework serves as a fixation for the cables' dead ends. The concrete blocks were attached to this framework. After that, they were stressed up to failure. Hairpin reinforcement were used to strengthen the blocks, and resist the applied stresses. Multiple round monostrands were also placed adjacent to each other to produce stress concentration in the concrete blocks. Numerical models were also constructed using finite element to simulate the experimental tests and validate the obtained results. The results were also compared to ACI provision.

15.
IUCrJ ; 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38597878

RESUMO

The Protein Data Bank (PDB) was established as the first open-access digital data resource in biology and medicine in 1971 with seven X-ray crystal structures of proteins. Today, the PDB houses >210 000 experimentally determined, atomic level, 3D structures of proteins and nucleic acids as well as their complexes with one another and small molecules (e.g. approved drugs, enzyme cofactors). These data provide insights into fundamental biology, biomedicine, bioenergy and biotechnology. They proved particularly important for understanding the SARS-CoV-2 global pandemic. The US-funded Research Collaboratory for Structural Bioinformatics Protein Data Bank (RCSB PDB) and other members of the Worldwide Protein Data Bank (wwPDB) partnership jointly manage the PDB archive and support >60 000 `data depositors' (structural biologists) around the world. wwPDB ensures the quality and integrity of the data in the ever-expanding PDB archive and supports global open access without limitations on data usage. The RCSB PDB research-focused web portal at https://www.rcsb.org/ (RCSB.org) supports millions of users worldwide, representing a broad range of expertise and interests. In addition to retrieving 3D structure data, PDB `data consumers' access comparative data and external annotations, such as information about disease-causing point mutations and genetic variations. RCSB.org also provides access to >1 000 000 computed structure models (CSMs) generated using artificial intelligence/machine-learning methods. To avoid doubt, the provenance and reliability of experimentally determined PDB structures and CSMs are identified. Related training materials are available to support users in their RCSB.org explorations.

16.
Phys Eng Sci Med ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598066

RESUMO

Healthy cornea guarantees the refractive power of the eye and the protection of the inner components, but injury, trauma or pathology may impair the tissue shape and/or structural organization and therefore its material properties, compromising its functionality in the ocular visual process. It turns out that biomechanical research assumes an essential role in analysing the morphology and biomechanical response of the cornea, preventing pathology occurrence, and improving/optimising treatments. In this review, ex vivo, in vivo and in silico methods for the corneal mechanical characterization are reported. Experimental techniques are distinct in testing mode (e.g., tensile, inflation tests), samples' species (human or animal), shape and condition (e.g., healthy, treated), preservation methods, setup and test protocol (e.g., preconditioning, strain rate). The meaningful results reported in the pertinent literature are discussed, analysing differences, key features and weaknesses of the methodologies adopted. In addition, numerical techniques based on the finite element method are reported, incorporating the essential steps for the development of corneal models, such as geometry, material characterization and boundary conditions, and their application in the research field to extend the experimental results by including further relevant aspects and in the clinical field for diagnostic procedure, treatment and planning surgery. This review aims to analyse the state-of-art of the bioengineering techniques developed over the years to study the corneal biomechanics, highlighting their potentiality to improve diagnosis, treatment and healing process of the corneal tissue, and, at the same, pointing out the current limits in the experimental equipment and numerical tools that are not able to fully characterize in vivo corneal tissues non-invasively and discourage the use of finite element models in daily clinical practice for surgical planning.

17.
Sci Rep ; 14(1): 8116, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582928

RESUMO

CO2 capture and storage in geological reservoirs have the potential to significantly mitigate the effects of anthropogenic gas emissions on global climate. Here, we report the results of the first laboratory experiments of CO2 injection in continental flood basalts of South America. The results show that the analyzed basalts have a mineral assemblage, texture and composition that efficiently allows a fast carbonate precipitation that starts 72 h after injection. Based on the availability of calcium, chemical monitoring indicates an estimated CO2 storage of ~ 75%. The carbonate precipitation led to the precipitation of aragonite (75.9%), dolomite (19.6%), and calcite (4.6%).

18.
Front Bioeng Biotechnol ; 12: 1297730, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38585709

RESUMO

Individuals exposed to the propagation of shock waves generated by the detonation of explosive charges may suffer Traumatic Brain Injury. The mechanism of cranial deflection is one of many hypotheses that could explain the observed brain damage. To investigate this physical phenomenon in a reproducible manner, a new simplified cranial substitute was designed with a mechanical response close to that of a human skull when subjected to this type of loading. As a first step, a Finite Element Model was employed to dimension the new substitute. The objective was indeed to obtain a vibratory behavior close to that of a dry human skull over a wide range of frequencies up to 10 kHz. As a second step, the Finite Element Model was used together with Experimental Modal Analyses to identify the vibration modes of the substitute. A shaker excited the structure via a metal rod, while a laser vibrometer recorded the induced vibrations at defined measurement points. The results showed that despite differences in material properties and geometry, the newly developed substitute has 10/13 natural frequencies in common with those of dry human skulls. When filled with a simulant of cerebral matter, it could therefore be used in future studies as an approximation to assess the mechanical response of a simplified skull substitute to a blast threat.

19.
Int J Environ Health Res ; : 1-12, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38576270

RESUMO

This study endeavoured to capitalize on prickly pear by-products for the optimization of molasses formulation, targeting elevated antioxidant capacities and superior sugar contents. Through robust statistical modelling, the optimal cooking parameters-temperature (70-80 °C) and duration (60-90 min)-were determined, guided by responses of antioxidant activity and Brix value. A D-Optimal mixture design further delineated the ideal proportions of molasses components (pulp, peel, and seeds). Characterization revealed that peel harboured the highest concentrations of total polyphenols (396.41 mg GAE/100g FW) and flavonoids (234.26 mg CE/100g FW), emphasizing its antioxidant potential (DPPH inhibition IC50: 12.72 µg/ml). The optimal cooking conditions were established at 78.35 °C for 79.70 min, with predictive equations guiding ingredient proportions (0.265 g pulp, 0.710 g peel, 0.025 g seed). Intriguingly, while peel inclusion enhanced total sugar content and antioxidant activity, seed incorporation exerted a contrasting effect by reducing total sugar content and limiting antioxidant activity.

20.
EBioMedicine ; 103: 105089, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38579363

RESUMO

Advances in radiation techniques have enabled the precise delivery of higher doses of radiotherapy to tumours, while sparing surrounding healthy tissues. Consequently, the incidence of radiation toxicities has declined, and will likely continue to improve as radiotherapy further evolves. Nonetheless, ionizing radiation elicits tissue-specific toxicities that gradually develop into radiation-induced fibrosis, a common long-term side-effect of radiotherapy. Radiation fibrosis is characterized by an aberrant wound repair process, which promotes the deposition of extensive scar tissue, clinically manifesting as a loss of elasticity, tissue thickening, and organ-specific functional consequences. In addition to improving the existing technologies and guidelines directing the administration of radiotherapy, understanding the pathogenesis underlying radiation fibrosis is essential for the success of cancer treatments. This review integrates the principles for radiotherapy dosimetry to minimize off-target effects, the tissue-specific clinical manifestations, the key cellular and molecular drivers of radiation fibrosis, and emerging therapeutic opportunities for both prevention and treatment.

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