11 Application of Accelerators and Storage Rings
709
were supplied to animals and humans and traced, with Geiger counters, in the
internal organs following the physiologic uptake. Today the same concept is used in
sophisticated diagnostics procedures as Single Photon Emission Computer Tomography (SPECT)—also called ‘scintigraphy’—and Positron Emission Tomography
(PET). Since the pioneering years, the challenge was to find the right radioisotope
that, as part of a molecule, would enter in the physiological processes and would
be preferably taken by a specific organ. The right isotopes must be chosen for
their half-life and decay type, both compatible with the physiology of the processes
investigated, the detection procedure, and the radiation protection of the patient.
Radio Phosphorus-32 (beta-emitter with half-life of 14.3 days), made from the
27-in. cyclotron was used as a tracer to study the absorption and metabolism of
phosphorus so that the cellular regeneration activity could be followed over several
weeks [46]. In 1936 John Lawrence gave for the first time Phosphorus-32 to a
leukemia patient beginning the therapeutic use of artificial radionuclides [47].
In 1936 radioactive Sodium-24 (half-life of 15 h), obtained at the Berkeley
cyclotron bombarding ordinary sodium with deuterium, was one of the first
artificial radioisotopes applied in physiology to study transport and uptake in
animal and humans and to determine the speed of absorption on the circulatory
system. Radioactive sodium was first given to treat leukemia patients by Hamilton
in 1937 [48].
In those years radionuclides were also used to study the transfer of traceable
elements and compounds across the cell membrane. Today cytopathology and
molecular biology are using radiotracers to study cellular diseases and physiology.
Larger cyclotrons were produced in the late 1930s at Berkeley, Harvard, and
Leningrad. Berkley’s 60-in. accelerator built in 1939 was used by Ernest Lawrence
to produce radioactive gasses (nitrogen, argon krypton, and xenon) that were used
to study the decompression sickness suffered by the aviators of the Second World
War. The 81m Kr gas is still used after 80 years in some studies of lung ventilation
and functionality.
At the time of the first experiments in humans, the effects of X-rays on healthy
biological tissues were known and avoiding overdose of ionizing radiation was a
concern. It is important to mention that in 1936 John Lawrence, comparing identical
doses of X-ray and neutrons [49], recognized different biological effects giving one
of the earliest contribution to the knowledge of radiation qualities in correlation with
internal and external radiotherapy and with radiation protection.
The isotope 131 of Iodine was selected by Joseph Gilbert Hamilton because its
half-live of 8 days was considered to be the optimal time to treat the thyroid and
avoid side effects to the patients. The radionuclide was isolated from a sample of
tellurium bombarded with deuterons and neutrons from the 37-in. cyclotron. From
1941 Iodine-131 was used in diagnostic of thyroid functionality and, from 1946,
in cancer therapy. In the 1950s Iodine-131, ingested as a liquid solution, became a
common treatment. Commercially producer in nuclear reactors, it dominated for 40
years the market of radiopharmaceuticals for cancer treatment and it is still widely
used today.
György Hevesy gave a decisive impulse to the studies with radiotracers of human
metabolism and physiological processes. He carried on a program, supported by
709
were supplied to animals and humans and traced, with Geiger counters, in the
internal organs following the physiologic uptake. Today the same concept is used in
sophisticated diagnostics procedures as Single Photon Emission Computer Tomography (SPECT)—also called ‘scintigraphy’—and Positron Emission Tomography
(PET). Since the pioneering years, the challenge was to find the right radioisotope
that, as part of a molecule, would enter in the physiological processes and would
be preferably taken by a specific organ. The right isotopes must be chosen for
their half-life and decay type, both compatible with the physiology of the processes
investigated, the detection procedure, and the radiation protection of the patient.
Radio Phosphorus-32 (beta-emitter with half-life of 14.3 days), made from the
27-in. cyclotron was used as a tracer to study the absorption and metabolism of
phosphorus so that the cellular regeneration activity could be followed over several
weeks [46]. In 1936 John Lawrence gave for the first time Phosphorus-32 to a
leukemia patient beginning the therapeutic use of artificial radionuclides [47].
In 1936 radioactive Sodium-24 (half-life of 15 h), obtained at the Berkeley
cyclotron bombarding ordinary sodium with deuterium, was one of the first
artificial radioisotopes applied in physiology to study transport and uptake in
animal and humans and to determine the speed of absorption on the circulatory
system. Radioactive sodium was first given to treat leukemia patients by Hamilton
in 1937 [48].
In those years radionuclides were also used to study the transfer of traceable
elements and compounds across the cell membrane. Today cytopathology and
molecular biology are using radiotracers to study cellular diseases and physiology.
Larger cyclotrons were produced in the late 1930s at Berkeley, Harvard, and
Leningrad. Berkley’s 60-in. accelerator built in 1939 was used by Ernest Lawrence
to produce radioactive gasses (nitrogen, argon krypton, and xenon) that were used
to study the decompression sickness suffered by the aviators of the Second World
War. The 81m Kr gas is still used after 80 years in some studies of lung ventilation
and functionality.
At the time of the first experiments in humans, the effects of X-rays on healthy
biological tissues were known and avoiding overdose of ionizing radiation was a
concern. It is important to mention that in 1936 John Lawrence, comparing identical
doses of X-ray and neutrons [49], recognized different biological effects giving one
of the earliest contribution to the knowledge of radiation qualities in correlation with
internal and external radiotherapy and with radiation protection.
The isotope 131 of Iodine was selected by Joseph Gilbert Hamilton because its
half-live of 8 days was considered to be the optimal time to treat the thyroid and
avoid side effects to the patients. The radionuclide was isolated from a sample of
tellurium bombarded with deuterons and neutrons from the 37-in. cyclotron. From
1941 Iodine-131 was used in diagnostic of thyroid functionality and, from 1946,
in cancer therapy. In the 1950s Iodine-131, ingested as a liquid solution, became a
common treatment. Commercially producer in nuclear reactors, it dominated for 40
years the market of radiopharmaceuticals for cancer treatment and it is still widely
used today.
György Hevesy gave a decisive impulse to the studies with radiotracers of human
metabolism and physiological processes. He carried on a program, supported by