Radiation Oncology

Three dimensional radiation therapy treatment planning requires radiation dose calculation using clinically acceptable algorithms. A parallel algorithm has been designed and analyzed to compute radiation dose in an irradiated volume by using equivalent tissue air ratio method. A speed-up of about 6 has been achieved through this technique.

Formulation of an optimized drug dose to initiate a specific biological process in a living organism is highly desirable in routine clinical practice. A personalized dosimetry can be tailored to address different pathological conditions specific to age, gender and sickness stage of a patient. Stronger drug doses may be needed to eliminate bacteria and cancerous cells in a patient. Milder doses of a drug are required to enhance healing through immunotherapy or biotherapy. Diluted drugs are intended in immunizations and vaccinations to ward off epidemic diseases. In short, an ideal drug should be optimized to produce intended results without any compromise to the patient’s wellbeing. A mathematical model has been developed to formulate required dose, and simulation result will be presented to quantify and optimize drugs dilution.

All chronic diseases evolve through different biological phases in a living system. The initial cellular insults are registered in the neurological networks that trigger various symptoms. These may include sensations, feelings, pains etc. Such systemic modulations produce anxiety, insomnia, loss of appetite, and other benign clinical conditions. A majority of such aberrant biological fluctuations are
resolved through cellular adaptations over time. However, cells under continuous stimulations for a prolong time, that fail to resolve, develop into lesions. Lesions generally produce inflammations in a
living organism. The unresolved inflammatory processes consequently lead to chemical productions. These chemicals include chemokines, cytokines, and tumor necrotic factors among others. Such
chemicals form the roots of most of the chronic diseases. Some of these unresolved chronic inflammatory processes develop into malignancies and other degenerative diseases. A chronic inflammatory
lesion can progress into different geometrical configurations based on the location of the insult and the structure of the target organ. The chronic inflammatory processes can be healed through cellular
apoptosis - a biological mechanism in which deformed cells in a tissue are absorbed by neighboring healthy cells. Assume that a lesion is comprised on n defective cells, the number of drug molecules
required to induce apoptosis is d, and the drug uptake factor in the target is p then one can compute the total dose, D, required to induce apoptosis as D=(n.d)/p. The drug dose may be modified over
time as the lesion is healed through apoptotic processes. Such healing processes shrink the lesion's surface area thus reducing the number of targets over time. This will result in dose deescalate with
time. The repetition of dose is dependent on the cell cycles. For example, if the target cell’s sensitivity lies in the M phase then the dose repetition time will be Tm=t2m-t1m, where t2m is the time when
the target cell leaves the sensitive phase and t1m is time when the target cell enters the sensitive phase. The duration of the treatment time depends on the size of the target lesion. Suppose a lesion
has l layers and if the treatment time to heal a single layer is r then the total treatment time, Tr, will be Tr=l.r. Simulation studies based on different lesion sizes, cell cycles and target layers show
reasonable time to heal chronic diseases. Administration of an appropriate dose of the selected drug in a latent chronic disease will yield optimal therapeutic effects with minimal side effects. The
intended dose is meant to seek out the defective cells in a lesion without any risk of overdose or side effects to normal tissues. The model basically addresses four parts of the drug dosimetry: The
initial quantity of the medicinal dose, repetition of dose, duration of dose and adjustment of dose over treatment time.

Abridged Background: Historically the notion of miasma has been used in different medical contexts. Miasma, as a cause and spread of epidemic diseases, was the most popular theory in the Nineteenth century Europe. This theory fell from grace when a different model was adopted to contain cholera. Europeans considered miasma as some form of obnoxious gas emanating from soil that was responsible for infectious diseases. Chinese held a similar concept about miasma during Ming Dynasty. They made extraordinary efforts to colonize and exploit their southwest frontiers. The prime objective of these Chinese ventures was to conquer the remote and desolate place infested with miasma. Indians were the first one in history who brought the illusive miasma concept into clinical practice. Paan, a Gambir paste, was considered to prevent miasma – an antimiasmatic application. Uncaris Gambir is water based extract from young branches and leaves of Gambir tree found in Southern India and Sri Lanka. A f...

The use of micro-scale drugs in combating various diseases has been in clinical practice for centuries around the world. Today the use of diluted drugs, in wide ranges, is prevalent both in conventional and complementary therapies. Minute drug doses derived from viruses, bacteria, hormones, and other modified substances are extensively used in immunization and vaccination therapies. Anti-venom drugs are another example of diluted drugs in clinical use to counter fatal effects of venomous bites. Frequent, regular and continuous administration of small drug doses for a long time, such as used in metronomic therapies, is highly desirable in treating chronic diseases. A whole discipline of complementary medicine, known as homeopathy, is based on diluted drugs. Some toxicological scientists have been examining the beneficial effects of diluted substances, including attenuated radiation, in living organism for decades. Scientific studies have revealed that different physical and chemical ...

MTLn3 cells derived from mouse mammary epithelium are known to be highly malig-nant and are resistant to both radio- and chemo-therapy. We exposed MTLn3 cells to var-ious doses of inorganic Arsenic trioxide (As2O3) in combination with ionizing radiation. Cells were treated with a series of As2O3 concentrations ranging from 20 µM to 1.22 nM for 8 hour, 24 hour and 48 hour periods. Post-treated cell proliferation was quantified by measuring mitochondrial activity and DNA analysis. Cells exposed to radiation and As2O3 at concentration greater than 1.25 µM showed apoptosis and radiations alone treated cells were statistically not different from the control. Hormesis was observed for As2O3 con-