Chemists have created a new class of fluorescent dyes that function in water and emit colors based solely on the diameter of circular nanotubes made of carbon and hydrogen. (Mehr in: Cancer News — ScienceDaily)
Researchers refine and run the first in vivo tests that use fluorescent nanotube-based probes to locate specific tumors in the body. The ability to pinpoint them with submillimeter accuracy could improve early detection and treatment of ovarian cancer. (Mehr in: Cancer News — ScienceDaily)
The mechanical resistance of tumors and collateral damage of standard treatments often hinder efforts to defeat cancers. However, a team of researchers has successfully softened malignant tumors by heating them. This method, called nanohyperthermia, makes the tumors more vulnerable to therapeutic agents. First, carbon nanotubes (CNTs) are directly injected into the tumors. Then, laser irradiation activates the nanotubes, while the surrounding healthy tissue remains intact. (Mehr in: Cancer News — ScienceDaily)
A ‚liquid biopsy‘ chip can trap and identify metastatic cancer cells in a small amount of blood drawn from a cancer patient. The breakthrough technology uses a simple mechanical method that has been shown to be more effective in trapping cancer cells than the microfluidic approach employed in many existing devices. The device captures cancer cells with antibodies attached to carbon nanotubes. (Mehr in: Cancer News — ScienceDaily)
Cells communicate with many varied signals—both chemical and electrical. Signals can be secreted in the space between cells, into the blood stream and in cerebrospinal fluid. Chemical signals can be sent in small vesicles (endosomes) or in nanotubes that exist between most cells. Another way that cells talk is by forming…
It is well known that neurons send a variety of intelligent critical signals to other neurons, glia, and immune cells using neurotransmitters, vesicles of several types, cytokines and nanotubes between cells. Elaborate back and forth communication between immune cells uses a wide variety of cytokines, neurotransmitters and…
Plant-based cellulose nanofibres do not pose a short-term health risk, especially short fibres, shows a study conducted in the context of National Research Programme „Opportunities and Risks of Nanomaterials“ (NRP 64). But lung cells are less efficient in eliminating longer fibres. (Mehr in: Pressemitteilungen – idw – Informationsdienst Wissenschaft)
The carcinogenic effect of various multi-walled carbon nanotubes (MWCNTs) after intraperitoneal injection in rats
Biological effects of tailor-made multi-walled carbon nanotubes (MWCNTs) without functionalization were investigated in vivo in a two-year carcinogenicity study. In the past, intraperitoneal carcinogenicity studies in rats using biopersistent granular dusts had always been negative, whereas a number of such studies with different asbestos fibers had shown tumor induction. The aim of this study was to identify possible carcinogenic effects of MWCNTs. We compared induced tumors with asbestos-induced mesotheliomas and evaluated their relevance for humans by immunohistochemical methods.
A total of 500 male Wistar rats (50 per group) were treated once by intraperitoneal injection with 109 or 5 × 109 WHO carbon nanotubes of one of four different MWCNTs suspended in artificial lung medium, which was also used as negative control. Amosite asbestos (108 WHO fibers) served as positive control. Morbid rats were sacrificed and necropsy comprising all organs was performed. Histopathological classification of tumors and, additionally, immunohistochemistry were conducted for podoplanin, pan-cytokeratin, and vimentin to compare induced tumors with malignant mesotheliomas occurring in humans.
Treatments induced tumors in all dose groups, but incidences and times to tumor differed between groups. Most tumors were histologically and immunohistochemically classified as malignant mesotheliomas, revealing a predominantly superficial spread on the serosal surface of the abdominal cavity. Furthermore, most tumors showed invasion of peritoneal organs, especially the diaphragm. All tested MWCNT types caused mesotheliomas. We observed highest frequencies and earliest appearances after treatment with the rather straight MWCNT types A and B. In the MWCNT C groups, first appearances of morbid mesothelioma-bearing rats were only slightly later. Later during the two-year study, we found mesotheliomas also in rats treated with MWCNT D – the most curved type of nanotubes. Malignant mesotheliomas induced by intraperitoneal injection of different MWCNTs and of asbestos were histopathologically and immunohistochemically similar, also compared with mesotheliomas in man, suggesting similar pathogenesis.
We showed a carcinogenic effect for all tested MWCNTs. Besides aspect ratio, curvature seems to be an important parameter influencing the carcinogenicity of MWCNTs.
Scientists have shown that gold nanotubes have many applications in fighting cancer: internal nanoprobes for high-resolution imaging; drug delivery vehicles; and agents for destroying cancer cells. (Mehr in: Cancer News — ScienceDaily)