ABSTRACT
The influence of the gadolinium-containing drug Dipentast (0.5 M water solution of sodium gadopentetate) on the antineoplastic efficacy of X-ray radiotherapy has been studied. Dipentast possesses neither intrinsic antitumor effect, nor tumor-seeking capability. Mice C57Bl/6 with transplanted adenocarcinoma Ca755 were used in the study. The mice were irradiated with an X-ray machine with an anode voltage of 200 kV. The absorbed dose in the tumor after irradiation was 10 Gy for both experimental and control groups. The mice in the experimental group were treated with a single intraperitoneal injection of 0.3 ml of Dipentast. The observation of the tumour growth rate has shown that intraperitoneal administration of Dipentast prior to X-ray irradiation results in a significant tumour growth delay (12 ± 1 days for the experimental group versus 2 ± 1 in the control group), increasing the median life span from 36 ± 1 days in the control group to 43 ± 1 days in the experimental group, and leads to complete disappearance of the tumour in 25 ± 1% of the animals in the experimental group, while in the control group, no tumour regression was observed.
Subject(s)
Antineoplastic Agents/administration & dosage , Breast Neoplasms/drug therapy , Gadolinium DTPA/administration & dosage , Animals , Breast Neoplasms/pathology , Breast Neoplasms/radiotherapy , Female , Humans , Mice , Neoplasm Transplantation , Radiation ToleranceABSTRACT
In this study efficacy of antineoplastic action of gadolinium NCT and boron NCT in cases of canine melanoma and osteosarcoma was compared. Canine spontaneous tumors, such as melanoma and osteosarcoma, have clinical common features with human malignancies, so these tumors in dogs can be considered as clinical model of human melanoma and osteosarcoma. The study has been carried out on 33 dogs with oral cavity melanoma and 9 dogs with osteosarcoma. Dogs with spontaneous melanoma of oral cavity and osteosarcoma of extremities were selected by the results of clinical examination. Irradiation was carried out at the NCT facility of the IRT MEPhI reactor. Neutron irradiation without boron or gadolinium was chosen as a control method to evaluate the efficacy of NCT.
Subject(s)
Boron Neutron Capture Therapy/veterinary , Dog Diseases/radiotherapy , Neoplasms/veterinary , Neutron Capture Therapy/veterinary , Animals , Bone Neoplasms/radiotherapy , Bone Neoplasms/veterinary , Boron Compounds/therapeutic use , Combined Modality Therapy , Dog Diseases/therapy , Dogs , Gadolinium/therapeutic use , Humans , Melanoma/radiotherapy , Melanoma/veterinary , Mouth Neoplasms/radiotherapy , Mouth Neoplasms/veterinary , Neoplasms/radiotherapy , Neoplasms/therapy , Osteosarcoma/radiotherapy , Osteosarcoma/veterinary , Phenylalanine/analogs & derivatives , Phenylalanine/therapeutic useABSTRACT
The purpose of the work was to build a prompt gamma neutron activation analysis (PGNAA) facility at the MEPhI reactor for analyzing the content of various elements for NCT. The facility was implemented on a monochromatic neutron beam. Methods of quantitative (10)B and Gd measurement have been developed for pharmacokinetic studies. The facility is capable of measuring 1 microg of (10)B and 10 microg of Gd in biological samples with an error less than 10%. The detection limit of the facility is 0.3 microg of (10)B and 2 microg of Gd. Neutron flux attenuation within biological tissue samples was estimated and a new system for determining the elemental concentration was suggested.
Subject(s)
Boron/analysis , Gadolinium/analysis , Neutron Activation Analysis/instrumentation , Animals , Boron/pharmacokinetics , Boron/therapeutic use , Boron Neutron Capture Therapy/statistics & numerical data , Gadolinium/pharmacokinetics , Gadolinium/therapeutic use , Gamma Rays , Humans , Isotopes/analysis , Isotopes/pharmacokinetics , Isotopes/therapeutic use , Mice , Neutron Activation Analysis/statistics & numerical data , Neutron Capture Therapy/statistics & numerical data , Nuclear Reactors , Russia , Tissue DistributionSubject(s)
Fistula/rehabilitation , Labyrinth Diseases/rehabilitation , Perilymph , Adult , Aged , Audiometry, Pure-Tone , Auditory Threshold , Combined Modality Therapy , Female , Fistula/diagnosis , Fistula/etiology , Humans , Labyrinth Diseases/diagnosis , Labyrinth Diseases/etiology , Male , Middle Aged , Recruitment Detection, Audiologic , Vestibular Function TestsABSTRACT
RATIONALE AND OBJECTIVES: The therapeutic effect of neutron capture therapy with the gadolinium (Gd) complex gadopentetate dimeglumine was studied in vivo in rats using a beam of thermal neutrons. METHODS: Rats with Jensen sarcomas 10-15 mm in diameter in their right thigh were irradiated with a thermal neutron beam that had fluences of 3.6 x 10(11) (20 min) or 5.4 x 10(11) n/cm2 (30 min) in the absence and presence of 5,500 or 13,750 ppm gadopentetate dimeglumine. Gadopentetate dimeglumine was administered directly into the tumor prior to neutron irradiation. Four groups of rats were studied: two groups of nonirradiated controls (Gd-n- and Gd+n-) and two irradiated groups (Gd-n+ and Gd+n+). In the follow-up period, we measured the subjects' clinical status and tumor size as a function of time postirradiation. RESULTS: In both control groups (Gd-n- and Gd+n-), the tumor progressively grew. Pure irradiation by thermal neutrons in the Gd-n+ group resulted in a transient inhibition of tumor growth with total regressions of 15%. Intratumoral administration of 13,750 ppm gadolinium per gram of tumor and subsequent neutron irradiation (the Gd+n+ group; fluence = 3.6.10(11) n/cm2) significantly increased the tumoricidal effects (i.e., decrease of tumor growth up to a complete regression of the tumors in about 80%). Treatment-specific differences between the groups were confirmed by histologic observations. CONCLUSION: The intratumoral administration of the hydrophilic magnetic resonance imaging contrast medium gadopentetate dimeglumine prior to irradiation with thermal neutrons leads to a therapeutic gain (i.e., reduction) on experimental Jensen sarcomas.
