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Adoptive cell therapy (ACT) is on the horizon as a thrilling therapeutic plan for cancer. However, widespread application of ACT is often restricted by several challenges, including complexity of priming tumor-specific T cells and poor trafficking in solid tumors. The convergence of nanotechnology and cancer immunotherapy is coming of age and could address the limitations of ACT. Recent studies have provided evidence on the application of magnetic nanoparticles (MNPs) to generate smart immune cells and to bypass problems associated with conventional ACT. Herein, we review current progress in the application of MNPs to improve preparing, guiding and tracking immune cells in cancer ACT. Besides, we comment on the challenges ahead and strategies to optimize MNPs for clinical settings.
[Box: see text].
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BACKGROUND: Israel is a regional "hotspot" of plastic pollution, with little discussion of potential adverse health effects from exposure to plastic. This review aims to stimulate discussion and drive policy by focusing on these adverse health effects. MAIN BODY: Plastics are synthetic polymers containing additives which can leach from food- and beverage-contact plastic into our food and beverages, and from plastic textiles onto our skin. Plastics persist in the environment for generations, fragmenting into MNPs: Micro (1 micron-5 mm)-Nano (1 nm-1 micron)-Plastic, which contaminate our atmosphere, water, and food chain. MNP can enter the human body through ingestion, inhalation and touch. MNP < 10 microns can cross epithelial barriers in the respiratory and gastrointestinal systems, and fragments < 100 nm can cross intact skin, enabling entry into body tissues. MNP have been found in multiple organs of the human body. Patients with MNP in atheromas of carotid arteries have increased risk of a combined measure of stroke, cardiovascular disease, and death. Toxic additives to plastics include bisphenols, phthalates, and PFAS, endocrine-disrupting chemicals (EDCs) which cause dysregulation of thyroid function, reproduction, and metabolism, including increased risk of obesity, diabetes, endometriosis, cancer, and decreased fertility, sperm count and quality. Fetal exposure to EDCs is associated with increased rates of miscarriages, prematurity and low birth weight. There is likely no safe level of exposure to EDCs, with increasing evidence of trans-generational and epigenetic effects. There are several existing Israeli laws to reduce plastic use and waste. Taxes on single-use plastic (SUP) were recently cancelled. There are many gaps in regulatory standards for food-, beverage- and child- safe plastic. Existing standards are poorly enforced. CONCLUSION: Reduction in production and use of plastic, promotion of recycling and reduction of leaching of toxic additives into our food and beverages are essential policy goals. Specific recommendations: Periodic monitoring of MNP in bottled beverages, food, indoor air; Strengthen enforcement of standards for food-, beverage-, and child-safe plastic; Renew tax on SUPs; National ban on SUP at public beaches, nature reserves and parks; Ban products manufactured with MNP; Increase research on sources and health outcomes of exposure to MNP and EDCs.
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Exposição Ambiental , Microplásticos , Plásticos , Humanos , Exposição Ambiental/efeitos adversos , Exposição Ambiental/legislação & jurisprudência , Exposição Ambiental/prevenção & controle , Política de Saúde/legislação & jurisprudência , Israel , Microplásticos/efeitos adversos , Microplásticos/análise , Microplásticos/química , Plásticos/efeitos adversos , Plásticos/análise , Plásticos/químicaRESUMO
Although the World Health Organization characterizes a One Health concern as one in which there is the capability to incorporate numerous disciplines to tackle health challenges threatening humans, animals and ecosystems, scientific efforts frequently remain compartmentalized. Here we report an original consortium, TORPP, spanning 16 disciplines, focused on Micro/NanoPlastics (MNPs) pollution as a One Health concern. Whereas the MNP topic has been largely studied in marine ecology, research effort remains scarce in human medicine. Equally, while marine ecology is highly skilled in MNP sampling and characterization, human medicine has developed pathophysiological concepts and tools that can be used more broadly to evaluate the health impact of MNPs. TORPP consortium propose that these strengths and knowledges must be transferred across fields of study to advance our understanding of MNP toxicity to organisms, by uniting integrative approaches (ecological, experimental and clinical) under a common conceptual and analytical framework.
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In Bangladesh, groundwater, the principal source of drinking water, contains predominantly high levels of iron. Drinking groundwater is associated with good iron status in populations. Against this backdrop, iron supplementation is often associated with side effects, which reduces its intake compliance. However, the level of iron in groundwater is not consistent, and low levels exist in many areas of the country. In the present study, we examined the role of groundwater with a low concentration of iron in the prevention of anemia in Bangladeshi children. In 2018, a cross-sectional study was conducted in Bangladesh among children aged 2-5 years (n = 122) who drank groundwater containing a low level of iron (0-<2 mg/L). The combined intake of iron was calculated from the key sources-diet, groundwater, and the simulated intake of MNPs. The intakes of iron were compared against the standard reference intake. The children's hemoglobin levels were measured using a photometer. The combined intake of iron from diet, groundwater with low levels of iron, and the simulated consumption of low-iron MNP in children was 5.8 ± 2.0 and 6.9 ± 2.5 mg/day, comprising 193% and 169% of the Estimated Average Requirements in the 2-3-year-old and 4-5-year-old subgroups, respectively. The combined intake of bioavailable iron from dietary and low-iron groundwater was 0.42 ± 0.023 and 0.22 ± 0.019 mg/day in children exposed to groundwater concentrations of 0.8-<2.0 mg/L and 0.0-<0.8 mg/L, respectively (p < 0.001). The mean concentration of hemoglobin in the respective groups was 12.17 ± 0.94 g/dL and 11.91 ± 0.91 g/dL (p = 0.30). The combined intake of iron from diet and the low-iron groundwater was associated with maintenance of hemoglobin concentration at the non-anemic level in > 90% of the children. The findings highlight the protective influence of the low concentration of iron in the drinking groundwater against childhood anemia in Bangladesh.
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Água Subterrânea , Ferro , População Rural , Humanos , Bangladesh/epidemiologia , Água Subterrânea/química , Água Subterrânea/análise , Estudos Transversais , Pré-Escolar , Masculino , Feminino , Ferro/administração & dosagem , Ferro/sangue , Anemia Ferropriva/prevenção & controle , Anemia Ferropriva/epidemiologia , Água Potável/química , Água Potável/análise , Hemoglobinas/análise , Suplementos Nutricionais , DietaRESUMO
There is a rising awareness of the toxicity of micro- and nanoplastics (MNPs); however, fundamental precise information on MNP-biodistribution in organisms is currently not available. X-ray fluorescence imaging (XFI) is introduced as a promising imaging modality to elucidate the effective MNP bioavailability and is expected to enable exact measurements on the uptake over the physical barriers of the organism and bioaccumulation in different organs. This is possible because of the ability of XFI to perform quantitative studies with a high spatial resolution and the possibility to conduct longitudinal studies. The focus of this work is a numerical study on the detection limits for a selected XFI-marker, here, palladium, to facilitate the design of future preclinical in vivo studies. Based on Monte Carlo simulations using a 3D voxel mouse model, the palladium detection thresholds in different organs under in vivo conditions in a mouse are estimated. The minimal Pd-mass in the scanning position at a reasonable significance level is determined to be <20 ng/mm2 for abdominal organs and <16 µg/mm2 for the brain. MNPs labelled with Pd and homogeneously distributed in the organ would be detectable down to a concentration of <1 µg/mL to <2.5 mg/mL in vivo. Long-term studies with a chronic MNP exposure in low concentrations are therefore possible such that XFI measurements could, in the future, contribute to MNP health risk assessment in small animals and humans.
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Magnetic nanoparticles (MNPs), particularly iron oxide nanoparticles (IONPs), play a pivotal role in biomedical applications ranging from magnetic resonance imaging (MRI) enhancement and cancer hyperthermia treatments to biosensing. This study focuses on the synthesis, characterization, and application of IONPs with two different size distributions for frequency mixing magnetic detection (FMMD), a technique that leverages the nonlinear magnetization properties of MNPs for sensitive biosensing. IONPs are synthesized through thermal decomposition and subsequent growth steps. Our findings highlight the critical influence of IONP size on the FMMD signal, demonstrating that larger particles contribute dominantly to the FMMD signal. This research advances our understanding of IONP behavior, underscoring the importance of size in their application in advanced diagnostic tools.
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At first, an organometallic catalyst namely, Pd-DPyE@MCM-41@MNP was prepared through magnetic (Fe3O4) nanoparticles-doped into channels of mesoporous silica MCM-41 and then, anchoring a novel complex composed of di(4-pyridyl)ethylene and palladium on the inner surface of the support. This immobilized catalyst was successfully identified via VSM, ICP-OES, TEM, FTIR, TGA, SEM, BET, XRD, EDX and elemental mapping analyses. After that, it was used as a versatile, heterogeneous, and magnetically reproducible catalyst in the generation of N,N'-alkylidene bisamides (1a-13a, 8-20 min, 90-98%, 50 °C, solvent-free) and Suzuki-Miyaura coupling (SMC) reaction derivatives (1b-26b, 10-140 min, 86-98%, 60 °C, PEG-400). The VSM plot of Pd-DPyE@MCM-41@MNP displays that this nanocatalyst can be easily recycled by applying an external magnetic field. In both synthetic paths, this nanocatalyst was reused at least seven times without palladium leaching and significantly reducing its catalytic performance. Also, stability and heterogeneous nature of catalyst were approved via ICP-OES technique and hot filtration test.
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Active and stable nonnoble electrocatalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) are required for water splitting by sustainable electricity. Here, Mn bonded with O and P is incorporated to modulate Co3S4 and Co2P respectively to enhance the catalytic activity and extend the catalyst lifetime. Mn3O4 adjusts the electronic structure of Co3S4 and Co atom fills the oxygen vacancy in Mn3O4. The interfacial interaction endows Co3S4/Mn3O4 to a lower reaction barrier due to ideal binding energies for OER intermediates. Structure stability of active sites and enhanced CoâS bonds by Operando Raman spectroscopy and theoretical calculations reduce the dissolution of Co3S4/Mn3O4, resulting in a lifetime of 500 h at 50 mA cm-2 for OER. The modulation of Co2P by MnP weakens the interaction between Co sites and adsorbed H*, achieving a high activity under a large current for HER. The assembled electrolyzer affords 50 mA cm-2 at 1.58 V and exhibits a lifetime of 350 h at 50 mA cm-2. The calculations disclose the electron interaction for the activity and stability, as well as the enhanced conductivity. The findings develop new avenues toward promoting catalytic activity and stability, making CoâMn bimetallic nanowires efficient electrocatalysts for nonnoble water electrolyzers.
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Magnetic hyperthermia therapy (MHT) is a re-emerging treatment modality for brain tumors where magnetic nanoparticles (MNPs) are locally delivered to the brain and then activated with an external alternating magnetic field (AMF) to generate localized heat at a site of interest. Due to the recent advancements in technology and theory surrounding the intervention, clinical and pre-clinical trials have demonstrated that MHT may enhance the effectiveness of chemotherapy and radiation therapy (RT) for the treatment of brain tumors. The future clinical success of MHT relies heavily on designing MNPs optimized for both heating and imaging, developing reliable methods for the local delivery of MNPs, and designing AMF systems with integrated magnetic particle imaging (MPI) for use in humans. However, despite the progression of technological development, the clinical progress of MHT has been underwhelming. This review aims to summarize the current state-of-the-art of MHT and offers insight into the current barriers and potential solutions for moving MHT forward.
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Tetrabromobisphenol A (TBBPA) and tetrabromobisphenol S (TBBPS) have been widely used as additives in various products; however, their residues damage human health mainly via dietary ingestion. The current detection techniques remain challenging in directly and sensitively identifying TBBPA and TBBPS from food samples. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) has great potential as an alternative tool for the analysis of low-mass environmental pollution. Herein, we successfully screened and optimized COOH-MNP-COOH as a novel MALDI matrix to enhance deprotonation for the analysis of TBBPA and TBBPS from animal-derived food samples in negative-ion mode. Notably, COOH-MNP-COOH was synthesized by a facile self-assembly strategy and characterized by TEM, FT-IR, UV-vis, and zeta potential analysis. Compared with conventional and control matrices, the COOH-MNP-COOH matrix exhibited excellent performance of TBBPA and TBBPS with high chemical stability, favorable reproducibility, remarkable salt and protein tolerance, and high sensitivity owing to abundant active groups, stronger UV-vis absorption at 355 nm, and better hydrophilicity and biocompatibility. TBBPA and TBBPS were detected with the assistance of an internal standard with limits of detection (LODs) of 300 and 200 pg/mL, respectively. Moreover, this method was applied to directly identify the residues of TBBPA and TBBPS in milk products, followed by basa catfish and meat. This research may provide a promising approach for the analysis of environmental pollutants in foodstuffs.
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Melaninas , Nanopartículas , Bifenil Polibromatos , Animais , Humanos , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Nanopartículas/químicaRESUMO
The development of new three-dimensional biomaterials with advanced versatile properties is critical to the success of tissue engineering (TE) applications. Here, (a) bioactive decellularized tendon extracellular matrix (dECM) with a sol-gel transition feature at physiological temperature, (b) halloysite nanotubes (HNT) with known mechanical properties and bioactivity, and (c) magnetic nanoparticles (MNP) with superparamagnetic and osteogenic properties were combined to develop a new scaffold that could be used in prospective bone TE applications. Deposition of MNPs on HNTs resulted in magnetic nanostructures without agglomeration of MNPs. A completely cell-free, collagen- and glycosaminoglycan- rich dECM was obtained and characterized. dECM-based scaffolds incorporated with 1%, 2% and 4% MNP-HNT were analysed for their physical, chemical, andin vitrobiological properties. Fourier-transform infrared spectroscopy, x-ray powder diffractometry and vibrating sample magnetometry analyses confirmed the presence of dECM, HNT and MNP in all scaffold types. The capacity to form apatite layer upon incubation in simulated body fluid revealed that dECM-MNP-HNT is a bioactive material. Combining dECM with MNP-HNT improved the thermal stability and compressive strength of the macroporous scaffolds upto 2% MNP-HNT.In vitrocytotoxicity and hemolysis experiments showed that the scaffolds were essentially biocompatible. Human bone marrow mesenchymal stem cells adhered and proliferated well on the macroporous constructs containing 1% and 2% MNP-HNT; and remained metabolically active for at least 21 din vitro. Collectively, the findings support the idea that magnetic nanocomposite dECM scaffolds containing MNP-HNT could be a potential template for TE applications.
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Nanotubos , Alicerces Teciduais , Humanos , Argila/química , Alicerces Teciduais/química , Estudos Prospectivos , Engenharia Tecidual/métodos , Fenômenos Magnéticos , Nanotubos/química , Matriz Extracelular/químicaRESUMO
An unexplored hybrid superporous hydrogel (MHSPH) of Dillenia indica fruit mucilage (DIFM) and carrageenan blend embedded with green synthesized magnesium oxide nanoparticles (MNPs) is utilized as an effective wound dressing material with appreciable mechanical strength in murine model. The prepared MNPs and the optimized MHSPH were characterized using X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared (FT- IR) spectroscopy. Size, zeta potential and morphology of MNPs was assessed using Dynamic light scattering technique (DLS) and field-emission scanning electron microscopy (FESEM) respectively. The MHSPH grades were further optimized using swelling study in phosphate buffer solution at pH 1.2, 7.0, and 8. Both MNPs and the optimized grade of MHSPH were evaluated based on hemolysis assay, and protein denaturation assays indicating them to be safe for biological use. Acute toxicity studies of the optimized MHSPH on Zebra fish model, revealed no observable toxic effect on the gill cells. Wound healing in Swiss albino mice with application of optimized grade of MHSPH took only 11 days for healing when compared to control mice where healing took 14 days, thus concluding that MHSPH as an effective dressing material as well as tissue regrowth scaffold.
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Dilleniaceae , Nanopartículas Metálicas , Nanopartículas , Animais , Camundongos , Carragenina/química , Hidrogéis/química , Óxido de Magnésio , Bandagens , Espectroscopia de Infravermelho com Transformada de Fourier , Antibacterianos/farmacologia , Nanopartículas Metálicas/químicaRESUMO
Frequency-mixing technology has been widely used to precisely identify magnetic nanoparticles in applications of quantitative biomedical detection in recent years. Examples include immune adsorption, lateral flow assays (LFAs), and biomagnetic imaging. However, the signals of magnetic response generated by adjacent magnetic samples interfere with each other owing to the small spacing between them in applications involving multi-sample detection (such as the LFA and multiplexing detection). Such signal interference prevents the biosensor from obtaining characteristic peaks related to the concentration of adjacent biomarkers from the magnetic response signals. Mathematical and physical models of the structure of sensors based on frequency-mixing techniques were developed. The theoretical model was verified and its key parameters were optimized by using simulations. A new frequency-mixing magnetic sensor structure was then designed and developed based on the model, and the key technical problem of signal crosstalk between adjacent samples was structurally solved. Finally, standard cards with stable magnetic properties were used to evaluate the performance of the sensor, and strips of the gastrin-17 (G-17) LFA were used to evaluate its potential for use in clinical applications. The results show that the minimum spacing between samples required by the optimized sensor to accurately identify them was only about 4-5 mm, and the minimum detectable concentration of G-17 was 11 pg mL-1 . This is a significant reduction in the required spacing between samples for multiplexing detection. The optimized sensor also has the potential for use in multi-channel synchronous signal acquisition, and can be used to detect synchronous magnetic signals in vivo.
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Técnicas Biossensoriais , Nanopartículas , Nanopartículas/química , Biomarcadores , Desenho de EquipamentoRESUMO
An electrocatalyst of single-atomic Mn sites with MnP nanoparticles (NPs) on N, P co-doped carbon substrate was constructed to enhance the catalytic activity of oxygen reduction reaction (ORR) through one-pot in situ doping-phosphatization strategy. The optimized MnSA-MnP-980â catalyst exhibits an excellent ORR activity in KOH electrolyte with a half-wave potential (E1/2) of 0.88 V (vs. RHE), and the ORR current density of MnSA-MnP-980â maintained 97.9 % for over 25000 s chronoamperometric i-t measurement. When using as the cathode, the MnSA-MnP-980â displays a peak power density of 51 mW cm-2 in Zinc-Air batteries, which observably outperformed commercial Pt/C (20 wt%). The X-ray photoelectron spectroscopy reveal that the doped P atoms with a strong electron-donating effectively enhances electron cloud density of Mn SAs sites, facilitating the adsorption of O2 molecules. Meanwhile, the introduction of MnP NPs can regulate the electronic structure of Mn SAs sites, making Mn SAs active sites exist in a low oxidation state and are less positively charged, which can supply electrons for ORR process to narrow the adsorption energy barrier of ORR intermediates. This work constructs novel active sites with excellent ORR properties and provides valuable reference for the development of practical application.
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Microplastic (MP) and nanoplastic (NP) could cause gut microbiota alterations. Although micro/nanoplastic (MNP) degradation is attracting increasing scientific interest, the evaluation of MNP reduction in gut needs to be further investigated. This study aimed to determine whether partial reduction of polystyrene MNP in gut could affect the immunity, gut microbiota and metabolome of mice. Serum eotaxin/CCL11 was at a lower level in the mice exposed to 200 µg and 500 µg NP (i.e., 2NP and 5NP groups, respectively) compared to those exposed to 500 µg MP (i.e., 5 MP group), while serum IL-2 and IL-4 were both greater in the 5NP group compared to the 5 MP group. The gut bacterial alpha diversity, fungal diversity and evenness were all similar among the MNP and control groups. However, the gut fungal richness was greater in both the 5NP and 5 MP groups compared to the control group. The gut bacterial and fungal compositions were both different between the MNP and control groups. Multiple gut bacteria and fungi showed different levels between the 2NP and 5NP groups, as well as between the 2NP and 5 MP groups. Increased Staphylococcus and decreased Glomus were determined in the 2NP group compared to both the 5NP and 5 MP groups. A Lactobacillus phylotype was found as the sole gatekeeper in the bacterial network of the 2NP group, while a Bifidobacterium phylotype contributed most to the stability of the bacterial networks of both the 5NP and 5 MP groups. Multiple differential gut metabolic pathways were found between the 2NP and 5NP/5 MP groups, and mTOR signaling pathway was largely upregulated in the 2NP group compared to both the 5NP and 5 MP groups. The relevant results could help with the evaluation of partial reduction of MNP in gut.
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Microbioma Gastrointestinal , Animais , Camundongos , Poliestirenos/farmacologia , Microplásticos , Plásticos/farmacologia , Metaboloma , BactériasRESUMO
Nanocomposites based on poly(lactic acid) (PLA) and magnetite nanoparticles (MNP-Fe3O4) show promise for applications in biomedical treatments. One key challenge is to improve the stabilization and dispersion of MNP-Fe3O4. To address this, we synthesized MNP-Fe3O4/PLA nanocomposites using ultrasound mediation and a single iron(II) precursor, eliminating the need for surfactants or organic solvents, and conducted the process under ambient conditions. The resulting materials, containing 18 and 33 wt.% Fe3O4, exhibited unique thermal behavior characterized by two mass losses: one at a lower degradation temperature (Td) and another at a higher Td compared to pure PLA. This suggests that the interaction between PLA and MNP-Fe3O4 occurs through hydrogen bonds, enhancing the thermal stability of a portion of the polymer. Fourier Transform Infrared (FT-IR) analysis supported this finding, revealing shifts in bands related to the terminal -OH groups of the polymer and the Fe-O bonds, thereby confirming the interaction between the groups. Raman spectroscopy demonstrated that the PLA serves as a protective layer against the oxidation of MNP-Fe3O4 in the 18% MNP-Fe3O4/PLA nanocomposite when exposed to a high-power laser (90 mW). Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) analyses confirmed that the synthetic procedure yields materials with dispersed nanoparticles within the PLA matrix without the need for additional reactants.
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The goal of the current investigation is to determine the breast tumor size-dependent MNP (Magnetic nano-particle) dose (mg/cm3) that can induce the required therapeutic effects during magnetic nanoparticle hyperthermia (MNH). The investigation is done through the MNH simulations on the tumor models generated from DCE_MRI DICOM images of breast cancer from TCIA ('The Cancer Imaging Archive'). Five tumor models are created from MRI data using 3D slicer software having size range of 3 cm3 to 15 cm3. The FEM-based solver (COMSOL multi-physics) is used to simulate bioheat transfer physics in all five extracted models. Single and multi-point injection strategies have been adopted to induce MNP in tumor tissues. The required MNP dose that may induce necessary therapeutic effects is evaluated by comparing the therapeutic effects produced by constant dose (CD) (5â mg/cm3) and variable reduced dose (RD) (5.5-2.8 mg/cm3) methodologies. Results show that for the requisite therapeutic effects, injected MNP dosesâ (mg/cm3) should not remain constant as the size of the tumor increases. In fact, MNP dose â (mg/cm3) should be reduced as the size of the tumor increases. Results also show that RD works better with a multi-injection strategy than a single injection of MNP. It has been found that the effective MNP dose â (mg/cm3) is reduced by 50 % for the biggest tumor size (15 cm3) using multi-injection MNP delivery with respect to the smallest tumor (3 cm3) selected in this study.
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Neoplasias da Mama , Hipertermia Induzida , Humanos , Feminino , Neoplasias da Mama/terapia , Modelos Teóricos , Fenômenos FísicosRESUMO
Plant pathogenic fungi and viruses are seriously threatening agricultural production. There is an urgent need to develop novel fungicides and antiviral agents with low toxicity and high efficiency. In this study, we designed and synthesized 32 thiazole-, hydrazone-, and amide-containing derivatives of laurene and systematically evaluated their antiviral activities and fungicidal activities. Structure-simplified compounds 5a-5c, 5i, 5k, 5l, 11a, 11j, and 12c displayed higher antiviral activities than that of ningnanmycin. Compound 11a with a simple chemical structure, convenient synthetic route, and excellent antiviral activity emerged as a secondary lead compound. The docking results show that compounds 5i, 5k, and 11a have strong interactions with the tobacco mosaic virus coat protein (TMV CP). These compounds also exhibited significant fungicidal activities. Compounds 5g, 5k, 11j, and 11l displayed 9.15-17.45 µg/mL EC50 values against Pyricularia grisea, and compounds 5h (EC50: 8.01 µg/mL) and 11i (EC50: 15.23 µg/mL) exhibited a similar level of EC50 values with chlorothalonil (EC50: 7.33 µg/mL) against Physalospora piricola. Preliminary fungicidal mechanism research indicated that compound 5h has a certain destructive effect on the hyphae of P. piricola. This work lays a foundation for the application of laurene derivatives in plant protection.
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To guide the treatment of malignant neuropathic pain (MNP) in clinical practice, by inoculating MADB-106 breast cancer cells into the right L4 nerve root in Sprague-Dawley rats, a rat model of MNP was established, providing basic conditions for the study of neuropathic pain and development and application of therapeutic drugs. As the tumor grew over time, it pressed the nerve roots, causing nerve damage. The spinal nerve ligation (SNL) model, which is a neuropathic pain model widely used in rats, was compared with the L4 nerve root SNL model, and histologic examination of the nerve tissue of both models was performed by electron microscopy. In addition to the infiltration and erosion of the L4 nerve by tumor cells, the tumor tissue gradually grew and compressed the L4 nerve roots, resulting in hyperalgesia of the rat's posterior foot on the operative side. Some spontaneous pain phenomena were also observed, such as constant lifting or licking of the posterior foot on the operative side under quiet conditions. Electron microscopy images showed that nerve injury was due to progressive compression by the tumor, cells of which were visualized, but the injury was lighter than that in SNL rats. Imaging showed a paravertebral tumor near the L4 nerve root in the carcinomatous neuropathic pain model rat. These results suggest that progressive compression of the nerve by a malignant tumor leads to nerve damage similar to the behavioral changes associated with chronic compression injury resulting from a loose ligature of the nerve. The cancer neuropathologic pain model at the L4 nerve root was successfully established in Sprague-Dawley rats.
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Neoplasias , Neuralgia , Ratos , Animais , Ratos Sprague-Dawley , Neuralgia/patologia , Nervos Espinhais/patologia , Hiperalgesia/complicações , Neoplasias/complicações , Gânglios Espinais/patologia , Ligadura/efeitos adversosRESUMO
Background: We described here an aptamer-based magnetic nanoprobe for measuring the amount of chloramphenicol (CAP) in milk. Methods: The nanoprobe presented in this method consists of a magnetic nanoparticle conjugated to a specific CAP aptamer. If the target is detected in the sample, the nanoprobe binds to it, and the aptamer forms a G-quadruplex structure. This structure mimics the peroxidase activity in the presence of the hemin cofactor. If tetramethylbenzidine is added to the sample containing the nanoprobe, a blue color light is observed. After adding a stop reagent solution, the color produced is measured by a microplate reader and a portable meter. Results: This study proves a 99% positive linear relationship between the microplate reader's results and the portable meter results. Conclusion: Conjugation of the aptamer to magnetic nanoparticles and applying magnetic separation operations change the nanoprobe performance by 11% for both mentioned devices.