Magnetic Composite Scaffolds for Potential Applications in Radiochemotherapy of Malignant Bone Tumors

Background and objectives: Cancer is the second leading cause of death globally, an alarming but expected increase. In comparison to other types of cancer, malignant bone tumors are unusual and their treatment is a real challenge. This paper’s main purpose is the study of the potential application of composite scaffolds based on biopolymers and calcium phosphates with the inclusion of magnetic nanoparticles in combination therapy for malignant bone tumors. Materials and Methods: The first step was to investigate if X-rays could modify the scaffolds’ properties. In vitro degradation of the scaffolds exposed to X-rays was analyzed, as well as their interaction with phosphate buffer solutions and cells. The second step was to load an anti-tumoral drug (doxorubicin) and to study in vitro drug release and its interaction with cells. The chemical structure of the scaffolds and their morphology were studied. Results: Analyses showed that X-ray irradiation did not influence the scaffolds’ features. Doxorubicin release was gradual and its interaction with cells showed cytotoxic effects on cells after 72 h of direct contact. Conclusions: The obtained scaffolds could be considered in further studies regarding combination therapy for malignant bone tumors.

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Rapid Fabrication of MgNH4PO4·H2O/SrHPO4 Porous Composite Scaffolds with Improved Radiopacity via 3D Printing Process

Biomedicines ◽

10.3390/biomedicines9091138 ◽

2021 ◽

Vol 9 (9) ◽

pp. 1138

Author(s):

Xiaofeng Cao ◽

Wufei Ge ◽

Yihu Wang ◽

Ming Ma ◽

Ying Wang ◽

...

Keyword(s):

3D Printing ◽

Bone Repair ◽

Magnesium Phosphate ◽

Porous Composite ◽

Composite Scaffolds ◽

X Ray ◽

P Elements ◽

Cellular Attachment ◽

Potential Applications

Although bone repair scaffolds are required to possess high radiopacity to be distinguished from natural bone tissues in clinical applications, the intrinsic radiopacity of them is usually insufficient. For improving the radiopacity, combining X-ray contrast agents with bone repair scaffolds is an effective method. In the present research, MgNH4PO4·H2O/SrHPO4 3D porous composite scaffolds with improved radiopacity were fabricated via the 3D printing technique. Here, SrHPO4 was firstly used as a radiopaque agent to improve the radiopacity of magnesium phosphate scaffolds. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) were used to characterize the phases, morphologies, and element compositions of the 3D porous composite scaffolds. The radiography image showed that greater SrHPO4 contents corresponded to higher radiopacity. When the SrHPO4 content reached 9.34%, the radiopacity of the composite scaffolds was equal to that of a 6.8 mm Al ladder. The porosity and in vitro degradation of the porous composite scaffolds were studied in detail. The results show that magnesium phosphate scaffolds with various Sr contents could sustainably degrade and release the Mg, Sr, and P elements during the experiment period of 28 days. In addition, the cytotoxicity on MC3T3-E1 osteoblast precursor cells was evaluated, and the results show that the porous composite scaffolds with a SrHPO4 content of 9.34% possessed superior cytocompatibility compared to that of the pure MgNH4PO4·H2O scaffolds when the extract concentration was 0.1 g/mL. Cell adhesion experiments showed that all of the scaffolds could support MC3T3-E1 cellular attachment well. This research indicates that MgNH4PO4·H2O/SrHPO4 porous composite scaffolds have potential applications in the bone repair fields.

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Scintigraphy with 99m Tc-Phosphonate and 67Gallium in Patients Suspected of Primary Bone Tumors

Nuklearmedizin ◽

10.1055/s-0037-1620567 ◽

1982 ◽

Vol 21 (04) ◽

pp. 136-139 ◽

Cited By ~ 2

Author(s):

C.-J. Edeling

Keyword(s):

Soft Tissue ◽

Bone Scintigraphy ◽

Primary Tumor ◽

Bone Tumors ◽

Whole Body ◽

Skeletal Metastases ◽

Malignant Bone Tumors ◽

67Ga Scintigraphy ◽

Primary Bone Tumors ◽

Primary Bone

Whole-body scintigraphy with both 99mTc-phosphonate and 67Ga was performed on 92 patients suspected of primary bone tumors. In 46 patients with primary malignant bone tumors, scintigraphy with 99mTc-phosphonate disclosed the primary tumor in 44 cases and skeletal metastases in 11, and 67Ga scintigraphy detected the primary tumor in 43 cases, skeletal metastases in 6 cases and soft-tissue metastases in 8 cases. In 25 patients with secondary malignant bone tumors, bone scintigraphy visualized a single lesion in 10 cases and several lesions in 15 cases, and 67Ga scintigraphy detected the primary tumor in 17 cases, skeletal metastases in 17 cases and soft-tissue metastases in 9 cases. In 21 patients with benign bone disease positive uptake of 99mTc-phosphonate was recognized in 19 cases and uptake of 67Ga in 17 cases. It is concluded that bone scintigraphy should be used in patients suspected of primary bone tumors. If malignancy is suspected, 67Ga scintigraphy should be performed in addition.

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MR-Derived CT-Like Images and Simulated Radiographs versus Conventional Radiography in Patients with Benign and Malignant Bone Tumors

10.1055/s-0038-1639518 ◽

2018 ◽

Author(s):

Alexandra Gersing ◽

Daniela Muenzel ◽

Felix Kopp ◽

Benedikt Schwaiger ◽

Carolin Knebel ◽

...

Keyword(s):

Bone Tumors ◽

Conventional Radiography ◽

Malignant Bone Tumors

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Neuroprotective and anti-amnestic effects of a combination therapy in a model of photochemical ischemic damage in the prefrontal cortex

ZHurnal «Patologicheskaia fiziologiia i eksperimental`naia terapiia» ◽

10.25557/0031-2991.2018.02.39-45 ◽

2018 ◽

pp. 39-45

Author(s):

Ф.М. Шакова ◽

Т.И. Калинина ◽

М.В. Гуляев ◽

Г.А. Романова

Keyword(s):

Prefrontal Cortex ◽

Nerve Growth Factor ◽

Growth Factor ◽

Combination Therapy ◽

Neuroprotective Effect ◽

Regulatory Protein ◽

Human Growth ◽

Neuroprotective Effects ◽

Nerve Growth

Цель исследования - изучение влияния комбинированной терапии (мутантные молекулы эритропоэтина (EPO) и дипептидный миметик фактора роста нервов ГК-2H) на воспроизведение условного рефлекса пассивного избегания (УРПИ) и объем поражения коры мозга у крыс с двусторонним ишемическим повреждением префронтальной коры. Методика. Мутантные молекулы EPO (MЕРО-TR и MЕPО-Fc) с значительно редуцированной эритропоэтической и выраженной цитопротекторной активностью созданы методом генной инженерии. Используемый миметик фактора роста нервов человека, эндогенного регуляторного белка, в экспериментах in vitro проявлял отчетливые нейропротективные свойства. Двустороннюю фокальную ишемию префронтальной коры головного мозга крыс создавали методом фотохимического тромбоза. Выработку и оценку УРПИ проводили по стандартной методике. Объем повреждения мозга оценивался при помощи МРТ. MEPO-TR и MEPO-Fc (50 мкг/кг) вводили интраназально однократно через 1 ч после фототромбоза, ГК-2Н (1 мг/кг) - внутрибрюшинно через 4 ч после фототромбоза и далее в течение 4 послеоперационных суток. Результаты. Выявлено статистически значимое сохранение выработанного до ишемии УРПИ, а также значимое снижение объема повреждения коры при комплексной терапии. Полученные данные свидетельствуют об антиамнестическом и нейропротекторном эффектах примененной комбинированной терапии, которые наиболее отчетливо выражены в дозах: МEPO-Fc (50 мкг/кг) и ГК-2Н (1 мг/кг). Заключение. Подтвержден нейропротекторный эффект и усиление антиамнестического эффекта при сочетанном применении мутантных производных эритропоэтина - MEPO-TR и MEPO-Fc и дипептидного миметика фактора роста нервов человека ГК-2H. The aim of this study was to investigate the effect of combination therapy, including mutant erythropoietin molecules (EPO) and a dipeptide mimetic of the nerve growth factor, GK-2H, on the conditioned passive avoidance (PA) reflex and the volume of injury induced by bilateral ischemia of the prefrontal cortex in rats. Using the method of genetic engineering the mutant molecules of EPO, MERO-TR and MEPO-Fc, with strongly reduced erythropoietic and pronounced cytoprotective activity were created. The used human nerve growth factor mimetic, an endogenous regulatory protein based on the b-bend of loop 4, which is a dimeric substituted dipeptide of bis- (N-monosuccinyl-glycyl-lysine) hexamethylenediamine, GK-2 human (GK-2H), has proven neuroprotective in in vitro experiments. Methods. Bilateral focal ischemic infarction was modeled in the rat prefrontal cortex by photochemically induced thrombosis. The PA test was performed according to a standard method. Volume of brain injury was estimated using MRI. MEPO-TR, and MEPO-Fc (50 mg/kg, intranasally) were administered once, one hour after the injury. GK-2Н (1 mg/kg, i.p.) was injected four hours after the injury and then for next four days. Results. The study showed that the complex therapy provided statistically significant retention of the PA reflex developed prior to ischemia and a significant decrease in the volume of injury. The anti-amnestic and neuroprotective effects of combination therapy were most pronounced at doses of MEPO-Fc 50 mg/kg and GK-2H 1 mg/kg. Conclusion. This study has confirmed the neuroprotective effect and enhancement of the anti-amnestic effect exerted by the combination of mutant erythropoietin derivatives, MEPO-TR and MEPO-Fc, and the dipeptide mimetic of human growth factor GK-2H.

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Radiosensitization of Prostate Cancers In Vitro and In Vivo to Erbium-filtered Orthovoltage X-rays Using Actively Targeted Gold Nanoparticles

Scientific Reports ◽

10.1038/s41598-017-18304-y ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 12

Author(s):

Allison M. Khoo ◽

Sang Hyun Cho ◽

Francisco J. Reynoso ◽

Maureen Aliru ◽

Kathryn Aziz ◽

...

Keyword(s):

Gold Nanoparticles ◽

X Rays ◽

Prostate Cancers

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Titanium-based composite scaffolds reinforced with hydroxyapatite-zirconia: Production, mechanical and in-vitro characterization

Journal of the Mechanical Behavior of Biomedical Materials ◽

10.1016/j.jmbbm.2021.104480 ◽

2021 ◽

Vol 118 ◽

pp. 104480

Author(s):

Mehmet Topuz ◽

Burak Dikici ◽

Mehmet Gavgali

Keyword(s):

Composite Scaffolds ◽

In Vitro Characterization

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Selection and Micropropagation of an Elite Melatonin Rich Tulsi (Ocimum sanctum L.) Germplasm Line

Agronomy ◽

10.3390/agronomy11020207 ◽

2021 ◽

Vol 11 (2) ◽

pp. 207

Author(s):

Mukund R. Shukla ◽

Annaliese Kibler ◽

Christina E. Turi ◽

Lauren A. E. Erland ◽

J. Alan Sullivan ◽

...

Keyword(s):

In Vitro Selection ◽

Integrated Approach ◽

Antioxidant Potential ◽

Ocimum Sanctum ◽

Natural Health Products ◽

Seed Population ◽

Health Products ◽

Potential Applications ◽

Medicinal Properties

Tulsi (Ocimum sanctum L.) is a sacred plant of medicinal and spiritual significance in many cultures. Medicinal properties of Tulsi are ascribed to its phytochemicals with antioxidant capabilities. The current study was undertaken to screen a large seed population of Tulsi to select germplasm lines with high antioxidant potential and to standardize protocols for micropropagation and biomass production to produce a phytochemically consistent crop. A total of 80 germplasm lines were established under in vitro conditions and screened for their antioxidant potential determined with the 2,2-diphenyl-1-picrylhydrazyl (DPPH) bioassay. The micropropagation of a selected line, named Vrinda, was established using nodal cultures grown on Murashige and Skoog medium containing benzylaminopurine (1.1 µM), gibberellic acid (0.3 µM), and activated charcoal (0.6%). The antioxidant phytohormones melatonin and serotonin were quantified in the field and greenhouse grown tissues of Vrinda and melatonin levels were found to be consistent in both conditions with higher serotonin levels under field conditions. This integrated approach combining the in vitro selection and propagation offers potential applications in the development of safe, effective, and novel natural health products of Tulsi, and many other medicinal plant species.

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Optimization of X-ray Investigations in Dentistry Using Optical Coherence Tomography

Sensors ◽

10.3390/s21134554 ◽

2021 ◽

Vol 21 (13) ◽

pp. 4554

Author(s):

Ralph-Alexandru Erdelyi ◽

Virgil-Florin Duma ◽

Cosmin Sinescu ◽

George Mihai Dobre ◽

Adrian Bradu ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Radiation Dose ◽

Imaging Techniques ◽

Image Resolution ◽

Optical Coherence ◽

X Rays ◽

High Quality ◽

X Ray

The most common imaging technique for dental diagnoses and treatment monitoring is X-ray imaging, which evolved from the first intraoral radiographs to high-quality three-dimensional (3D) Cone Beam Computed Tomography (CBCT). Other imaging techniques have shown potential, such as Optical Coherence Tomography (OCT). We have recently reported on the boundaries of these two types of techniques, regarding. the dental fields where each one is more appropriate or where they should be both used. The aim of the present study is to explore the unique capabilities of the OCT technique to optimize X-ray units imaging (i.e., in terms of image resolution, radiation dose, or contrast). Two types of commercially available and widely used X-ray units are considered. To adjust their parameters, a protocol is developed to employ OCT images of dental conditions that are documented on high (i.e., less than 10 μm) resolution OCT images (both B-scans/cross sections and 3D reconstructions) but are hardly identified on the 200 to 75 μm resolution panoramic or CBCT radiographs. The optimized calibration of the X-ray unit includes choosing appropriate values for the anode voltage and current intensity of the X-ray tube, as well as the patient’s positioning, in order to reach the highest possible X-rays resolution at a radiation dose that is safe for the patient. The optimization protocol is developed in vitro on OCT images of extracted teeth and is further applied in vivo for each type of dental investigation. Optimized radiographic results are compared with un-optimized previously performed radiographs. Also, we show that OCT can permit a rigorous comparison between two (types of) X-ray units. In conclusion, high-quality dental images are possible using low radiation doses if an optimized protocol, developed using OCT, is applied for each type of dental investigation. Also, there are situations when the X-ray technology has drawbacks for dental diagnosis or treatment assessment. In such situations, OCT proves capable to provide qualitative images.

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Synthesis and Characterization of Polyvinylpyrrolidone-Modified ZnO Quantum Dots and Their In Vitro Photodynamic Tumor Suppressive Action

International Journal of Molecular Sciences ◽

10.3390/ijms22158106 ◽

2021 ◽

Vol 22 (15) ◽

pp. 8106

Author(s):

Tianming Song ◽

Yawei Qu ◽

Zhe Ren ◽

Shuang Yu ◽

Mingjian Sun ◽

...

Keyword(s):

Quantum Dots ◽

Photodynamic Therapy ◽

Inhibitory Effect ◽

Therapeutic Effects ◽

In Vivo Experiments ◽

Potential Applications ◽

Zno Quantum Dots ◽

Zno Qds

Despite the numerous available treatments for cancer, many patients succumb to side effects and reoccurrence. Zinc oxide (ZnO) quantum dots (QDs) are inexpensive inorganic nanomaterials with potential applications in photodynamic therapy. To verify the photoluminescence of ZnO QDs and determine their inhibitory effect on tumors, we synthesized and characterized ZnO QDs modified with polyvinylpyrrolidone. The photoluminescent properties and reactive oxygen species levels of these ZnO/PVP QDs were also measured. Finally, in vitro and in vivo experiments were performed to test their photodynamic therapeutic effects in SW480 cancer cells and female nude mice. Our results indicate that the ZnO QDs had good photoluminescence and exerted an obvious inhibitory effect on SW480 tumor cells. These findings illustrate the potential applications of ZnO QDs in the fields of photoluminescence and photodynamic therapy.

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