The adsorption properties of two zeolite types, faujasite (NaY, ZnY, CoY) and LTA-4A zeolite (NaA, ZnA, CoA), towards technetium were studied in batch static experiments. The Si/Al ratio, acidity, ...dealumination, chargebalance cations of zeolite, contact time and temperature determined the adsorption efficiency. The maximum removal efficiency of 98.8% and
K
d
value (2.06 × 10
−4
cm
3
g
−1
) was achieved using CoY (zeolite type Y). The kinetics of technetium adsorption followed the pseudo-second order model. The TcO
2
adsorption is mainly due to the hydrogen bonds between protons of the zeolitic structural OH groups (Bronsted acid center) and oxygen from the TcO
2
−
.
Abstract In the present study, we compared the effects of nanocrystalline fullerene suspension (nanoC60 ) on tumour cell growth in vitro and in vivo. NanoC60 suspension was prepared by solvent ...exchange using tetrahydrofuran to dissolve C60 . In vitro, nanoC60 caused oxidative stress, mitochondrial depolarization and caspase activation, leading to apoptotic and necrotic death in mouse B16 melanoma cells. Biodistribution studies demonstrated that intraperitoneally injected radiolabeled (125 I) nanoC60 readily accumulated in the tumour tissue of mice subcutaneously inoculated with B16 cells. However, intraperitoneal administration of nanoC60 over the course of two weeks starting from melanoma cell implantation not only failed to reduce, but significantly augmented tumour growth. The tumour-promoting effect of nanoC60 was accompanied by a significant increase in splenocyte production of the immunoregulatory free radical nitric oxide (NO), as well as by a reduction in splenocyte proliferative responses to T- and B-cell mitogens ConcanavalinA and bacterial lipopolysaccharide, respectively. A negative correlation between NO production and splenocyte proliferation indicated a possible role of NO in reducing the proliferation of splenocytes from nanoC60 -injected mice. These data demonstrate that nanoC60 , in contrast to its potent anticancer activity in vitro, can potentiate tumour growth in vivo, possibly by causing NO-dependent suppression of anticancer immune response.
The adsorption properties of two zeolite types, faujasite (NaY, ZnY, CoY) and LTA-4A zeolite (NaA, ZnA, CoA), towards technetium were studied in batch static experiments. The Si/Al ratio, acidity, ...dealumination, chargebalance cations of zeolite, contact time and temperature determined the adsorption efficiency. The maximum removal efficiency of 98.8% and K.sub.d value (2.06 x 10.sup.-4 cm.sup.3 g.sup.-1) was achieved using CoY (zeolite type Y). The kinetics of technetium adsorption followed the pseudo-second order model. The TcO.sub.2 adsorption is mainly due to the hydrogen bonds between protons of the zeolitic structural OH groups (Bronsted acid center) and oxygen from the TcO.sub.2.sup.-.
In the present study, we compared the effects of nanocrystalline fullerene suspension (nanoC
60) on tumour cell growth in vitro and in vivo. NanoC
60 suspension was prepared by solvent exchange using ...tetrahydrofuran to dissolve C
60. In vitro, nanoC
60 caused oxidative stress, mitochondrial depolarization and caspase activation, leading to apoptotic and necrotic death in mouse B16 melanoma cells. Biodistribution studies demonstrated that intraperitoneally injected radiolabeled (
125I) nanoC
60 readily accumulated in the tumour tissue of mice subcutaneously inoculated with B16 cells. However, intraperitoneal administration of nanoC
60 over the course of two weeks starting from melanoma cell implantation not only failed to reduce, but significantly augmented tumour growth. The tumour-promoting effect of nanoC
60 was accompanied by a significant increase in splenocyte production of the immunoregulatory free radical nitric oxide (NO), as well as by a reduction in splenocyte proliferative responses to T- and B-cell mitogens ConcanavalinA and bacterial lipopolysaccharide, respectively. A negative correlation between NO production and splenocyte proliferation indicated a possible role of NO in reducing the proliferation of splenocytes from nanoC
60-injected mice. These data demonstrate that nanoC
60, in contrast to its potent anticancer activity in vitro, can potentiate tumour growth in vivo, possibly by causing NO-dependent suppression of anticancer immune response.
The aim of this study was to develop a dual-modality PET/MR imaging probe by radiolabeling iron oxide magnetic nanoparticles (IONPs), surface functionalized with water soluble stabilizer ...2,3-dicarboxypropane-1,1-diphosphonic acid (DPD), with the positron emitter Gallium-68. Magnetite nanoparticles (Fe3O4 MNPs) were synthesized via coprecipitation method and were stabilized with DPD. The Fe3O4-DPD MNPs were characterized based on their structure, morphology, size, surface charge, and magnetic properties. In vitro cytotoxicity studies showed reduced toxicity in normal cells, compared to cancer cells. Fe3O4-DPD MNPs were successfully labeled with Gallium-68 at high radiochemical purity (>91%) and their stability in human serum and in PBS was demonstrated, along with their further characterization on size and magnetic properties. The ex vivo biodistribution studies in normal Swiss mice showed high uptake in the liver followed by spleen. The acquired PET images were in accordance with the ex vivo biodistribution results. Our findings indicate that Ga68-Fe3O4-DPD MNPs could serve as an important diagnostic tool for biomedical imaging.
In the present study, we compared the effects of nanocrystalline fullerene suspension (nanoC(60)) on tumour cell growth in vitro and in vivo. NanoC(60) suspension was prepared by solvent exchange ...using tetrahydrofuran to dissolve C(60). In vitro, nanoC(60) caused oxidative stress, mitochondrial depolarization and caspase activation, leading to apoptotic and necrotic death in mouse B16 melanoma cells. Biodistribution studies demonstrated that intraperitoneally injected radiolabeled (125I) nanoC(60) readily accumulated in the tumour tissue of mice subcutaneously inoculated with B16 cells. However, intraperitoneal administration of nanoC(60) over the course of two weeks starting from melanoma cell implantation not only failed to reduce, but significantly augmented tumour growth. The tumour-promoting effect of nanoC(60) was accompanied by a significant increase in splenocyte production of the immunoregulatory free radical nitric oxide (NO), as well as by a reduction in splenocyte proliferative responses to T- and B-cell mitogens ConcanavalinA and bacterial lipopolysaccharide, respectively. A negative correlation between NO production and splenocyte proliferation indicated a possible role of NO in reducing the proliferation of splenocytes from nanoC(60)-injected mice. These data demonstrate that nanoC(60), in contrast to its potent anticancer activity in vitro, can potentiate tumour growth in vivo, possibly by causing NO-dependent suppression of anticancer immune response.
Abstract Because of the ability to induce cell death in certain conditions, the fullerenes (C60 ) are potential anticancer and toxic agents. The colloidal suspension of crystalline C60 (nano-C60 , n ...C60 ) is extremely toxic, but the mechanisms of its cytotoxicity are not completely understood. By combining experimental analysis and mathematical modelling, we investigate the requirements for the reactive oxygen species (ROS)-mediated cytotoxicity of different n C60 suspensions, prepared by solvent exchange method in tetrahydrofuran (THF/ n C60 ) and ethanol (EtOH/ n C60 ), or by extended mixing in water (aqu/ n C60 ). With regard to their capacity to generate ROS and cause mitochondrial depolarization followed by necrotic cell death, the n C60 suspensions are ranked in the following order: THF/ n C60 >EtOH/ n C60 >aqu/ n C60 . Mathematical modelling of singlet oxygen (1 O2 ) generation indicates that the1 O2 -quenching power (THF/ n C60 <EtOH/ n C60 <aqu/ n C60 ) of the solvent intercalated in the fullerene crystals determines their ability to produce ROS and cause cell damage. These data could have important implications for toxicology and biomedical application of colloidal fullerenes.
Introduction: Scintigrafic imaging of infection and inflammation is of special interest in nuclear medicine diagnostic of infectious or inflammatory diseases. For this purpose various radiolabelled ...compounds have been explored. The aim: The aim of this study was to find out whether 99mTc-PYP posses capability to bind to Staphylococcus aureus, and possibilities for its use in bacterial infection and inflammation not only in non-specific way. Methodology: 99mTc-PYP has been used for imaging infective and non-infective skeletal diseases. Protein binding, lypophilicity measurements and in vitro binding to viable and dead bacteria of 99mTc-PYP with 3 different concentrations of sodium pyrophosphate decahydrate were studied. Wistar rats were used in all biodistribution evaluations. Results: All 99mTc-PYP samples were on high radiochemical purity, with high protein binding and hydrophilic character. In vitro investigations have shown that the uptake of 99mTc-PYP to Staphylococcus aureus was depended on concentration of pyrophosphate decahydrate in the samples. Thus the highest uptake to viable Staphylococcus aureus (>30 %) was obtained in the sample with 0.10 mg pyrophosphate decahydrate/1 ml. The in vivo investigation results on rats shown increased radioactivity in the infected thigh muscle (T/NT>2.3) and intensify bone uptake (5.4 ÷ 6.9 % ID/g). Conclusion: Considering that the diagnosis of bone or joint infection remains a challenging problem, it is obvious how important is to investigate whether 99mTc-PYP could be used as a specific agent for bacterial infection in the axial skeleton.
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