Biomaterial Database

Potential for therapeutic gain similar to pions by daily combinations of neutrons and low-LET radiations. 1979

M M Kligerman

Biological studies with negative pi mesons (pions) at the Los Alamos Meson Physics Facility (LAMPF) have shown a relatively constant reduction of shoulder of the survival curve for single cell cultures and relatively constant reduction in the no response region for multicellular tumor spheroids (MTS) with little change in sensitivity (or slope), in both single dose and fractionated experiments. In clinical studies, a trend toward therapeutic gain for pions has been demonstrated in patients treated at LAMPF, with marked, rapid turmor regression for relatively mild acute normal tissue injury and no untoward effects observed over 7 to 24 months. Since the pion beams used therapeutically at LAMPF are characterized by a small amount of high-linear-energy-transfer (LET) radiation (in the range 10 to 20%), it is hypothesized that pion radiation as compared to x-rays increased the differential tolerance to sublethal injury in favor of normal tissues, resulting in therapeutic gain. It is further proposed that the near simultaneous application of high-LET radiation (such as neutrons) and low-LET radiation (such as x-rays) might create a bilogical situation similar to that of pion treatment, potentially resulting in therapeutic gain, although without the added benefit of dose localization obtainable with pions.

UI	MeSH Term	Description	Entries
D009369	Neoplasms	New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms.	Benign Neoplasm,Cancer,Malignant Neoplasm,Tumor,Tumors,Benign Neoplasms,Malignancy,Malignant Neoplasms,Neoplasia,Neoplasm,Neoplasms, Benign,Cancers,Malignancies,Neoplasias,Neoplasm, Benign,Neoplasm, Malignant,Neoplasms, Malignant
D011878	Radiotherapy	The use of IONIZING RADIATION to treat malignant NEOPLASMS and some benign conditions.	Radiotherapy, Targeted,Targeted Radiotherapy,Radiation Therapy,Radiation Therapy, Targeted,Radiation Treatment,Targeted Radiation Therapy,Radiation Therapies,Radiation Therapies, Targeted,Radiation Treatments,Radiotherapies,Radiotherapies, Targeted,Targeted Radiation Therapies,Targeted Radiotherapies,Therapies, Radiation,Therapies, Targeted Radiation,Therapy, Radiation,Therapy, Targeted Radiation,Treatment, Radiation
D011879	Radiotherapy Dosage	The total amount of radiation absorbed by tissues as a result of radiotherapy.	Dosage, Radiotherapy,Dosages, Radiotherapy,Radiotherapy Dosages
D002470	Cell Survival	The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.	Cell Viability,Cell Viabilities,Survival, Cell,Viabilities, Cell,Viability, Cell
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D004601	Elementary Particles	Individual components of atoms, usually subatomic; subnuclear particles are usually detected only when the atomic nucleus decays and then only transiently, as most of them are unstable, often yielding pure energy without substance, i.e., radiation.	Baryons,Fundamental Particles,Baryon,Elementary Particle,Fundamental Particle,Particle, Elementary,Particle, Fundamental,Particles, Elementary,Particles, Fundamental
D004735	Energy Transfer	The transfer of energy of a given form among different scales of motion. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed). It includes the transfer of kinetic energy and the transfer of chemical energy. The transfer of chemical energy from one molecule to another depends on proximity of molecules so it is often used as in techniques to measure distance such as the use of FORSTER RESONANCE ENERGY TRANSFER.	Transfer, Energy
D005214	Fast Neutrons	Neutrons, the energy of which exceeds some arbitrary level, usually around one million electron volts.	Fast Neutron,Neutron, Fast,Neutrons, Fast
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia