Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 37
Filter
Add more filters










Publication year range
1.
Int J Cancer ; 135(3): 519-28, 2014 Aug 01.
Article in English | MEDLINE | ID: mdl-24122662

ABSTRACT

Autophagy is an intracellular molecular pathway that maintains cellular homeostasis. A role for autophagy in the development as well as in the treatment of gynecologic malignancies, while still under-investigated, is receiving increased interest. Depending on concomitant factors, autophagy can either promote or suppress development of cervical, endometrial and ovarian cancer. Moreover, these cancer cells can utilize autophagy to promote its resistance to chemotherapeutic agents or, conversely, autophagy can enhance the efficacy of cytotoxic agents by promoting autophagic cell death. In this review the key autophagy-related mechanisms in development and treatment of cervical, endometrial and ovarian cancer are elucidated and evaluated.


Subject(s)
Autophagy , Endometrial Neoplasms/pathology , Ovarian Neoplasms/pathology , Uterine Cervical Neoplasms/pathology , Antineoplastic Agents/therapeutic use , Endometrial Neoplasms/drug therapy , Female , Humans , Male , Ovarian Neoplasms/drug therapy , Uterine Cervical Neoplasms/drug therapy
2.
J Nanosci Nanotechnol ; 13(6): 4394-7, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23862509

ABSTRACT

White organic light-emitting devices (OLEDs) were fabricated by combining a blue OLED with a color conversion layer made of mixed Y3Al5O12:Ce3+ green and Ca2AlO19:Mn4+ red phosphors. The X-ray diffraction patterns showed that Ce3+ ions in the Y3Al5O12:Ce3+ phosphors completely substituted for the Y3+ ions and the Mn4+ ions in the CaAl12O19:Mn4+ phosphors completely substituted for the Ca2+ ions. Electroluminescence spectra at 11 V for the OLEDs fabricated utilizing a color conversion layer showed that the Commission Internationale de l'Eclairage coordinates for the Y3Al5O12:Ce3+ and CaAl12O19:Mn4+ phosphors mixed at the ratio of 1:5 and 1:10 were (0.31, 0.34) and (0.32, 0.37), respectively, indicative of a good white color.

3.
Acta Psychiatr Scand ; 118(3): 200-8, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18699953

ABSTRACT

OBJECTIVE: Dopamine dysregulation has been implicated in the pathophysiology of schizophrenia. The present study was performed to examine whether unaffected relatives at high genetic risk of schizophrenia have dopamine dysregulation in comparison with healthy controls. METHOD: Eleven unaffected relatives from families with two or more first- or second-degree relatives with schizophrenia (n = 9) or with a monozygotic schizophrenic twin (n = 2) and 11 age- and sex-matched controls were examined using positron emission tomography (PET) with [(11)C] raclopride. Subjects also underwent extensive neuropsychological testing. RESULTS: Subjects with high genetic risk showed a loss of asymmetry of D(2) receptors in the putamen in comparison with healthy controls. In addition, they showed significantly poorer performance on neuropsychological tests than controls. CONCLUSION: Our results suggest that dopamine dysregulation and neuropsychological dysfunction may be present in subjects at high genetic risk of schizophrenia. However, further studies are required to confirm these findings.


Subject(s)
Family/psychology , Functional Laterality/genetics , Genetic Predisposition to Disease/psychology , Putamen/physiopathology , Receptors, Dopamine D2/genetics , Schizophrenia/genetics , Adolescent , Adult , Brain/diagnostic imaging , Brain/physiopathology , Cognition Disorders/diagnosis , Cognition Disorders/genetics , Cognition Disorders/psychology , Female , Genetic Markers/genetics , Humans , Imaging, Three-Dimensional , Magnetic Resonance Imaging , Male , Neuropsychological Tests/statistics & numerical data , Positron-Emission Tomography/methods , Young Adult
4.
Clin Pharmacol Ther ; 81(2): 252-8, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17259948

ABSTRACT

YKP1358 is a novel serotonin (5-HT(2A)) and dopamine (D(2)) antagonist that, in preclinical studies, fits the general profile of an atypical antipsychotic. We conducted a D(2) receptor occupancy study with YKP1358 in healthy volunteers using positron emission tomography (PET) to measure the D(2) receptor occupancy of YKP1358 and to characterize its relationship to plasma drug concentrations. A single oral dose, parallel group, dose-escalation (100, 200, and 250 mg) study was performed in 10 healthy male volunteers with the PET radiotracer [(11)C]raclopride. The D(2) receptor occupancy of striatum was measured pre-dose, and at 2, 5, and 10 h after YKP1358 administration. Serial blood samples were taken for measurement of plasma YKP1358 concentrations. D(2) receptor occupancy by YKP1358 increased to 53-83% at 2 h, and then decreased afterwards, ranging from 40-64% at 5 h to 20-51% at 10 h. The YKP1358 dose-plasma concentration relationship exhibited extensive variability, but there was a good relationship between plasma concentrations and D(2) receptor occupancy that was well predicted by a sigmoid E(max) model using nonlinear mixed effects modeling. To our knowledge, this is the first study in which the relationship between plasma concentration and the biomarker of D(2) receptor occupancy was modeled using nonlinear mixed effects modeling. It is anticipated that these results will be useful in estimating for subsequent studies the initial doses of YKP1358 required to achieve a therapeutically effective range of D(2) receptor occupancy.


Subject(s)
Antipsychotic Agents/pharmacokinetics , Brain/metabolism , Dopamine Antagonists/pharmacokinetics , Positron-Emission Tomography/methods , Receptors, Dopamine D2/metabolism , Administration, Oral , Adult , Algorithms , Alkaloids/administration & dosage , Alkaloids/blood , Alkaloids/pharmacokinetics , Antipsychotic Agents/administration & dosage , Antipsychotic Agents/blood , Area Under Curve , Carbon Radioisotopes , Dopamine Antagonists/administration & dosage , Dopamine Antagonists/blood , Dopamine D2 Receptor Antagonists , Dose-Response Relationship, Drug , Half-Life , Humans , Male , Models, Biological
6.
Hear Res ; 196(1-2): 33-8, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15464299

ABSTRACT

It has been reported that the area of decreased glucose metabolism in the FDG-PET of prelingually deaf children correlates significantly with speech performance after cochlear implantation. In this study, we undertook to confirm changes of glucose metabolism in the cerebral cortex using an animal model with age-matching groups to completely exclude the influence of age differences between the deaf and normal-hearing groups. The cochlea was ablated bilaterally at a postnatal 10-14 days in the deaf groups; 3-4 deaf and normal rats were included at each time point at 1, 2, 4 and 8 weeks and 7 months after ablation. After injecting 2-deoxyglucose intraperitoneally, digitalized autoradiographic images were obtained, and analyzed by using two different methods; 3-dimensional voxel-wise statistical analysis and conventional 2-dimensional densitometry. The hypometabolic area analyzed using 3-dimensional analysis and the differences of optical density between normal and deaf as determined by densitometry were widest and most prominent between 4 and 8 weeks after ablation. Differences were not significant before 2 weeks or after 7 months after ablation. This result shows that the hypometabolic area becomes prominent after a critical period and it decreases as the duration of deafness increases. We believe that cross-modal plasticity may be the mechanism of changes in glucose metabolism and that this result reinforced the usefulness of evaluating hypometabolic area using FDG-PET in deaf children.


Subject(s)
Auditory Pathways/metabolism , Deafness/metabolism , Deoxyglucose/pharmacokinetics , Animals , Animals, Newborn/growth & development , Animals, Newborn/metabolism , Auditory Cortex/metabolism , Auditory Pathways/diagnostic imaging , Auditory Pathways/physiopathology , Autoradiography , Cerebral Cortex/metabolism , Deafness/diagnostic imaging , Deafness/physiopathology , Densitometry , Deoxyglucose/administration & dosage , Electronic Data Processing , Fluorodeoxyglucose F18 , Geniculate Bodies/metabolism , Glucose/metabolism , Inferior Colliculi/metabolism , Injections, Intraperitoneal , Neuronal Plasticity , Positron-Emission Tomography , Radiopharmaceuticals , Rats , Rats, Sprague-Dawley
7.
Nucl Med Commun ; 25(1): 11-7, 2004 Jan.
Article in English | MEDLINE | ID: mdl-15061260

ABSTRACT

To clarify the biological significance of [18F]fluorodeoxyglucose (18F-FDG) accumulation in patients with cancer, we assessed the relationships between 18F-FDG uptake and glucose transporter-1 (GLUT-1) expression and proliferation rate in human glioma and lung cancer. We obtained FDG PET images and measured standardized uptake values (SUVs) of primary tumours in 13 patients with brain glioma and 25 patients with non-small-cell lung cancer. After surgery, portions of respected tumours were obtained, and the proliferation rate was measured as proliferation index (per cent of (S+G2+M)/(G0+G1+S+G2+M)) using DNA flow cytometry. The expression of GLUT-1 in a tumour was evaluated by using immunostaining. We classified GLUT-1 expression as grade 0 (no positive cell), grade 1 (< 10% cells positive), grade 2 (11-50% cells positive) and grade 3 (51-100% cells positive). Based on the expression of GLUT-1, cases with grades 0, 1, 2 and 3 showed SUVs of 6.1 +/- 2.8, 5.0 +/- 3.2, 8.3 +/- 3.3 and 10.4 +/- 6.6, respectively (P < 0.05). Non-small-cell lung cancer showed higher FDG uptake (SUV, 8.5 +/- 5.1) and higher GLUT-1 expression (grade, 2.0 +/- 1.0) than did brain glioma (SUV, 4.7 +/- 2.5; grade, 0.8 +/- 0.8). Based on the total number of cases, SUVs did not relate to proliferation index (r = 0.19). In non-small-cell lung cancer, SUVs did not correlate with proliferation index, whereas in glioma, SUVs were strongly related to proliferation index (r = 0.79, P < 0.01). In conclusion, FDG uptake generally correlated with GLUT-1 expression in non-small-cell lung cancer and glioma. In the case of glioma, FDG uptake also indicated increased cellular proliferation, which was not demonstrated in non-small-cell lung cancer.


Subject(s)
Biomarkers, Tumor/metabolism , Fluorodeoxyglucose F18/pharmacokinetics , Glioma/metabolism , Glioma/pathology , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Monosaccharide Transport Proteins/metabolism , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Carcinoma, Non-Small-Cell Lung/diagnostic imaging , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Cell Division , Female , Gene Expression Regulation, Neoplastic , Glioma/diagnostic imaging , Glucose Transporter Type 1 , Humans , Lung Neoplasms/diagnostic imaging , Male , Middle Aged , Radionuclide Imaging , Radiopharmaceuticals/pharmacokinetics , Reproducibility of Results , Sensitivity and Specificity , Statistics as Topic
8.
Nucl Med Commun ; 24(6): 689-96, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12766606

ABSTRACT

Radiation synovectomy is a useful treatment modality in patients with refractory synovitis. We have developed a 188Re-tin-colloid as a new radiopharmaceutical agent and investigated its efficacy and safety in patients with rheumatoid arthritis. Radiation synovectomy was performed using 188Re-tin-colloid in 22 knees from 21 rheumatoid arthritis patients refractory to intra-articular corticosteroid injection. The efficacy and safety of administration of 370-1110 MBq of 188Re-tin-colloid were evaluated after 1, 3, 6, 9 and 12 months. Pain intensity on a visual analogue scale decreased significantly 12 months after therapy (mean+/-SD: 68.0+/-26.1 mm vs. 25.1+/-23.4 mm; P=0.0001 by the paired t-test). Pain decreased in 19 cases (86.3%), joint tenderness improved in 14 cases (63.6%) and joint swelling was reduced in all cases (100%). 188Re-tin-colloid was safe. The residual activity of 188Re in the blood was 0.077%+/-0.25% of the injected dose. The radioactivity of 188Re in the urine was 0.14%+/-0.13% of the injected dose. Transient reactive synovitis was observed in 18 cases (81.8%). No clinical side-effects or abnormalities in leucocyte count, platelet count, liver function tests or urine analysis were observed in any patient. In conclusion, in this first study of radiation synovectomy using 188Re-tin-colloid for patients with rheumatoid arthritis, the treatment resulted in the improvement of arthritis and was well tolerated.


Subject(s)
Arthritis, Rheumatoid/radiotherapy , Knee Joint/radiation effects , Radiopharmaceuticals/therapeutic use , Rhenium/therapeutic use , Tin/therapeutic use , Female , Humans , Joint Diseases/etiology , Male , Middle Aged , Pain/etiology , Radiopharmaceuticals/adverse effects , Rhenium/adverse effects , Tin/adverse effects , Treatment Outcome
9.
Nucl Med Commun ; 23(9): 865-70, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12195091

ABSTRACT

The aim of this study was to determine whether quantitative information obtained from [(18)F]fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) has a prognostic significance for patients with non-small cell lung cancer (NSCLC). We investigated (18)F-FDG PET imaging of 73 patients with NSCLC. The maximum standardized uptake value (SUV(max)) was significantly different between the histopathological types of tumour (squamous cell carcinoma (n=37, 12.4+/-5.1), adenocarcinoma (n=30, 8.2+/-5.8), bronchioloalveolar carcinoma (n=4, 2.6+/-1.7), <0.01). In the univariate analysis of all patients, staging (P=0.0001), tumour cell type (P=0.013), and a SUV(max) greater than 7 (P=0.0011) was correlated with survival. However, a multivariate analysis identified staging and SUV(max) greater than 7 were affected survival adversely. The mortality rate of patients with group I disease (stage I to stage IIIA) was 5.8 times lower than that of patients with group II disease (stage IIIB to stage IV). Patients with a high SUV(max) (> or =7) had a 6.3 times higher mortality than those with a low SUV(max)(<7). By multivariate analysis of patients with squamous cell carcinoma, only grouping affected survival (P=0.008, relative risk=4.3). In the case of adenocarcinoma, the SUV(max) (>10) correlated exclusively with poorer survival (P=0.031, relative risk=11.152). (18)F-FDG uptake correlated with survival in NSCLC. Especially in adenocarcinomas, the SUV(max) was complementary to other known prognostic factors.


Subject(s)
Carcinoma, Non-Small-Cell Lung/diagnostic imaging , Carcinoma, Non-Small-Cell Lung/mortality , Fluorodeoxyglucose F18 , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/mortality , Adult , Aged , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Female , Fluorodeoxyglucose F18/pharmacokinetics , Humans , Korea/epidemiology , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Male , Middle Aged , Multivariate Analysis , Neoplasm Staging , Prognosis , Radiopharmaceuticals/pharmacokinetics , Retrospective Studies , Statistics as Topic , Survival Rate , Tomography, Emission-Computed
10.
Nucl Med Commun ; 23(3): 237-42, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11891481

ABSTRACT

Radioisotope-labelled lipiodol has been used in the therapy of liver cancer. Recently a lipiodol solution of 188Re-labelled diaminedithiol (DD) has been reported to show a high uptake in the liver cancer. We synthesized long-chain alkyl DD derivatives to improve their uptake and retention in tissue. As the length of the alkyl chain increased, tissue uptake and retention also increased due to hydrophobic interaction with lipiodol. Among the synthesized compounds, the lipiodol solution of 188Re-HDD, the DD derivative with the longest side chain (C16), is a promising agent for therapy of liver cancer.


Subject(s)
Iodized Oil/pharmacokinetics , Liver Neoplasms/metabolism , Organometallic Compounds/chemical synthesis , Organometallic Compounds/pharmacokinetics , Radiopharmaceuticals/chemical synthesis , Radiopharmaceuticals/pharmacokinetics , Animals , Humans , Liver Neoplasms/radiotherapy , Lung/metabolism , Mice , Mice, Inbred ICR , Organometallic Compounds/therapeutic use , Radiopharmaceuticals/therapeutic use , Tissue Distribution
11.
Nucl Med Commun ; 23(1): 75-81, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11748441

ABSTRACT

This study was undertaken in order to prepare 188Re labelled ethylenediamine-N,N,N',N'-tetrakis(methylene phosphonic acid) (EDTMP), and to determine its potential as a therapeutic radiopharmaceutical for the palliation of metastatic bone pain. The effects of pH, incubation methods, and concentrations of stannous chloride, EDTMP, and ammonium perrhenate as a carrier on radiochemical yield and stability were evaluated. Biodistribution studies were performed in male Wistar rats after intravenous injection of 188Re-EDTMP and compared with those of hydroxyethylidene diphosphonate (HEDP). Greater than 95% radiochemical yield of 188Re-EDTMP was obtained under the optimal conditions (0.1 mmol x ml(-1) of EDTMP, 0.5 mg x ml(-1) of stannous chloride, and pH 1.0). Heating the reaction mixture (boiling water for 15 min, and microwave heating for 15 s) and the addition of ammonium perrhenate increased the radiochemical stability (>90% at 3 h, and >80% at 48 h). The biodistribution of 188Re-EDTMP showed high bony uptake and rapid clearance from other organs, and high bone-to-soft tissue ratios, which are similar to 188Re-HEDP. In conclusion, 188Re-EDTMP was prepared with high radiochemical yield and stability, and showed favourable biological characteristics. Microwave heating was a convenient and rapid method for the preparation of 188Re-EDTMP. It is considered that 188Re-EDTMP is a potential therapeutic agent for bone metastasis.


Subject(s)
Bone Neoplasms/secondary , Organometallic Compounds/chemical synthesis , Organometallic Compounds/therapeutic use , Pain, Intractable/drug therapy , Radiopharmaceuticals/chemical synthesis , Radiopharmaceuticals/therapeutic use , Animals , Bone Neoplasms/physiopathology , Hydrogen-Ion Concentration , Indicators and Reagents , Isotope Labeling/methods , Ligands , Male , Organometallic Compounds/pharmacokinetics , Pain, Intractable/etiology , Radioisotopes/pharmacokinetics , Radioisotopes/therapeutic use , Radiopharmaceuticals/pharmacokinetics , Rats , Rats, Wistar , Reducing Agents , Tissue Distribution
12.
Ann Acad Med Singap ; 30(5): 542-5, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11603144

ABSTRACT

INTRODUCTION: The aim of this study was to investigate the potential of using 188Re Lipiodol for selective internal radiation therapy of inoperable hepatocellular carcinoma (HCC). CLINICAL PICTURE: A 33-year-old female with poorly-differentiated multicentric HCC, elevated alpha-fetoprotein (AFP) and increased serum alkaline phosphatase. TREATMENT: Over a 2-month interval, the patient was treated twice with 4GBq of 188Re-TDD-Lipiodol. OUTCOMES: There was good localisation of 188Re Lipiodol in the tumours, but also in thyroid (first treatment) and gastrointestinal tract (both treatments). So far (5 months post-treatment), the patient remains well with stable disease. CONCLUSIONS: 188Re Lipiodol can be an effective radiopharmaceutical for the treatment of HCC; however, more work must be done to minimise the uptake in bowel.


Subject(s)
Antineoplastic Agents/therapeutic use , Carcinoma, Hepatocellular/radiotherapy , Iodized Oil , Liver Neoplasms/radiotherapy , Organometallic Compounds/therapeutic use , Radiopharmaceuticals/therapeutic use , Adult , Antineoplastic Agents/administration & dosage , Female , Humans , Organometallic Compounds/administration & dosage , Radiopharmaceuticals/administration & dosage , Radiotherapy Dosage
13.
Eur J Nucl Med ; 28(5): 639-45, 2001 May.
Article in English | MEDLINE | ID: mdl-11383871

ABSTRACT

The sodium/iodide symporter (NIS) is known to be responsible for the active accumulation of iodide within the thyroid gland. We evaluated the relationship between the expression of NIS in primary or lymph node lesions and iodine-131 uptake in recurrent lesions of differentiated thyroid cancer. In 67 patients with differentiated thyroid cancer (5 follicular and 62 papillary carcinomas), the expression of NIS was analysed by immunohistochemical staining using polyclonal antibodies against human NIS. We used paraffin block tissues of primary tumours or metastatic lesions, and also assessed 131I uptake in recurrent lesions of thyroid cancer on post-operative 131I whole-body scan. Immunohistochemical staining was positive in 22 patients (32.8%), including 2 of 5 follicular and 20 of 62 papillary carcinomas. Recurrence was confirmed in 40 patients pathologically or clinically by serum thyroglobulin, 131I scan, fluorine-18 fluorodeoxyglucose positron emission tomography and/or computed tomography. Among these 40 patients, 28 showed positive uptake on 131I scan. Fourteen tumour specimens out of 28 (50%) were positive by NIS immunohistochemical staining. The remaining 12 patients with recurrent cancer showed negative 131I scans, and all specimens were negative by NIS immunohistochemical staining. Thus, NIS immunohistochemical staining predicted 131I uptake in recurrent cancer with a 100% positive predictive value and a 46.2% negative predictive value. There was no difference in the positivity of NIS according to the site of recurrence on 131I scan. Outcome of 131I therapy could be assessed in 22 of the 28 patients who showed 131I uptake in recurrent lesions. Patients with positive NIS immunostaining responded to 131I therapy better than did patients with negative immunostaining (P<0.05). In conclusion, NIS immunohistochemical staining showed a high positive predictive value in predicting iodine uptake. Positive immunohistochemical staining of human NIS in primary or lymph node lesions may predict 131I accumulation and effectiveness of 131I therapy in recurrent lesions.


Subject(s)
Adenocarcinoma, Follicular/diagnostic imaging , Carcinoma, Papillary/diagnostic imaging , Iodine Radioisotopes , Symporters/metabolism , Thyroid Neoplasms/diagnostic imaging , Adenocarcinoma, Follicular/metabolism , Adenocarcinoma, Follicular/radiotherapy , Adenocarcinoma, Follicular/secondary , Adolescent , Adult , Aged , Bone Neoplasms/diagnostic imaging , Bone Neoplasms/secondary , Carcinoma, Papillary/metabolism , Carcinoma, Papillary/radiotherapy , Carcinoma, Papillary/secondary , Female , Fluorodeoxyglucose F18 , Humans , Immunohistochemistry , Iodine Radioisotopes/pharmacokinetics , Iodine Radioisotopes/therapeutic use , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/secondary , Lymph Nodes/metabolism , Lymphatic Metastasis , Male , Middle Aged , Neoplasm Recurrence, Local/diagnostic imaging , Neoplasm Recurrence, Local/metabolism , Predictive Value of Tests , Radiopharmaceuticals , Sensitivity and Specificity , Thyroid Neoplasms/metabolism , Thyroid Neoplasms/pathology , Thyroid Neoplasms/radiotherapy , Tomography, Emission-Computed
14.
Nucl Med Biol ; 28(2): 197-204, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11295430

ABSTRACT

Radiolabeled lipiodol has been used for targeting liver cancer. We developed a lipiodol solution of (188)Re-TDD (2,2,9,9-tetramethyl-4,7-diaza-1,10-decanedithiol) and investigated its feasibility for the treatment of liver cancer. The lipiodol solution of (188)Re-TDD was well-retained in the lipiodol phase in vitro. After injection through the tail veins of mice, high lung-uptake was investigated which is evidence of embolizing activity. We also found high accumulation in hepatoma after injection through the hepatic arteries of hepatoma-bearing rats. In conclusion, the lipiodol solution of (188)Re-TDD is a promising agent for liver cancer therapy.


Subject(s)
Iodized Oil , Liver Neoplasms, Experimental/radiotherapy , Liver Neoplasms/radiotherapy , Organometallic Compounds/chemical synthesis , Radiopharmaceuticals/chemical synthesis , Animals , Liver/diagnostic imaging , Liver/metabolism , Lung/metabolism , Mice , Organometallic Compounds/pharmacokinetics , Organometallic Compounds/therapeutic use , Radioisotopes , Radionuclide Imaging , Radiopharmaceuticals/pharmacokinetics , Radiopharmaceuticals/therapeutic use , Rats , Rats, Sprague-Dawley , Rhenium , Solutions , Tissue Distribution
16.
Appl Radiat Isot ; 52(4): 851-5, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10800721

ABSTRACT

As a generator-produced beta-emitting radionuclide, the importance of 188Re for radionuclide therapy is increasing rapidly. We prepared 188Re-tin colloid and compared its properties with 188Re-sulfur colloid. Labeling efficiencies reached >98% for tin colloid at 2 h and 89-94% for sulfur colloid at 3 h. All the preparations were stable for 72 h in water, serum, and synovial fluid. If labeled at higher temperature, the particle size of tin colloid increased. The residual radioactivity of 188Re-sulfur colloid in disposable polypropylene syringes after injecting mice was high (62.0+/-7.0%) due to its hydrophobic nature, while that of 188Re-tin colloid was low (2.9+/-1.6%). Although both 188Re-tin colloid and 188Re-sulfur colloid might be useful for radionuclide therapy, we conclude that 188Re tin colloid is more advantageous over 188Re sulfur colloid, due to higher labeling efficiency, control of the particle size, and lower residual activity in the injection syringes.


Subject(s)
Radiopharmaceuticals/pharmacokinetics , Rhenium/pharmacokinetics , Sulfur/pharmacokinetics , Synovial Membrane/radiation effects , Tin/pharmacokinetics , Animals , Male , Mice , Mice, Inbred ICR , Rabbits , Radiopharmaceuticals/chemical synthesis , Radiopharmaceuticals/therapeutic use , Sulfur/therapeutic use , Synovial Fluid/metabolism , Tissue Distribution
17.
Exp Eye Res ; 70(3): 329-37, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10712819

ABSTRACT

Amniotic membrane (AM) contains basement membrane components and various proteinase inhibitors. Furthermore, when used as a graft, the basement membrane of AM could block inflammatory insults to a damaged corneal surface. Thus, we evaluated whether amniotic membrane patching could promote the healing process by inhibiting proteolytic damage. Alkali wounds were inflicted on the central corneas of rabbits by applying a round filter paper, 6.0 mm in diameter, soaked in 1 N NaOH for 30 sec. Amniotic membrane patching was performed over the perilimbal sclera immediately after wounding. A total of 115 rabbits were divided into four groups: (1) immediately covered by AM with the amnion cell side down up to the perilimbal sclera (n =26); (2) covered by AM with the stromal side down up to the perilimbal sclera (n =19); (3) anchored to the fornix (n =29); and (4) uncovered as a control (n =41). AM was removed 3 days postoperatively. During follow-ups, epithelial defects, corneal thickness and its opacity of each eye were measured. Some corneas were removed for histopathologic studies and for proteinase activity assay and zymography. The epithelial healing was faster and the corneal thickness was thicker in all three AM-covered groups than in the control (P<0.05). No significant difference was found between covered and anchored groups (P>0.05). Corneal opacity was least in the amnion cell side down group. Infiltration of polymorphonuclear leukocytes (PMNs) was much less in AM-covered groups than in the control. Pathological results were associated with zymographic findings, which revealed much higher proteinase activity in uncovered group than AM-covered groups. Immediate intervention for acute alkali burns with AM as a temporary patch promotes wound healing by inhibiting proteinase activity and PMNs infiltration.


Subject(s)
Biological Dressings , Burns, Chemical/therapy , Corneal Injuries , Endopeptidases/metabolism , Eye Burns/therapy , Animals , Burns, Chemical/enzymology , Burns, Chemical/pathology , Cornea/enzymology , Cornea/pathology , Corneal Opacity/therapy , Eye Burns/enzymology , Eye Burns/pathology , Female , Male , Rabbits , Wound Healing
18.
Eur J Nucl Med ; 27(1): 76-82, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10654151

ABSTRACT

To examine the possibility of using rhenium-188 diethylene triamine penta-acetic acid (DTPA) for endovascular intra-balloon brachytherapy after angioplasty, dose distribution around the balloon was calculated and validated by film dosimetry. Medical internal radiation dosimetry (MIRD) was calculated assuming that the balloon had ruptured and that the contents had been released into the systemic circulation. 188Re-perrhenate eluate from the 188W/188Re generator was concentrated using an ion column and used to label DTPA. The dose distribution around the angioplasty balloon (20 mm length, 3 mm diameter cylinder) was estimated by Monte Carlo simulation using the EGS4 code. The time required for 17.6 Gy to be absorbed at 1 mm from the balloon's surface following application of 3700 MBq/ml of 188Re was found to be 278 s. Fifty percent of the energy was deposited in the first millimetre of the vessel wall from the balloon's surface. The calculated radiation absorbed dose agreed with that measured by film dosimetry, which was performed using a water phantom, with errors ranging from 9.4% to 17%. Upon balloon rupture the total amount of 188Re-DTPA was presumed to enter the systemic circulation. The resulting radiation absorbed dose was calculated using the MIRDOSE3 program and residence times obtained from dogs and amounted to 0.0056 mGy/MBq to the whole body and 4.56 mGy/MBq to the urinary bladder. The absorbed dose of 188Re-DTPA to the whole body was one-tenth of that of 188Re-perrhenate. A window-based program was developed to calculate the exposure time and the radiation dose absorbed as a function of the 188Re concentration and the arbitrary distance from the balloon to the surrounding tissues. We conclude that 188Re-DTPA is easy to prepare, safe to use and suitable for intra-balloon brachytherapy after coronary angioplasty.


Subject(s)
Angioplasty, Balloon, Coronary , Brachytherapy , Coronary Disease/therapy , Pentetic Acid/therapeutic use , Rhenium/therapeutic use , Animals , Coronary Disease/radiotherapy , Dogs , Radioisotopes , Radiometry , Recurrence
19.
Ann Nucl Med ; 13(5): 303-8, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10582799

ABSTRACT

The purpose of this study was to evaluate the effect of tumor size on the uptake of 18F-fluorodeoxyglucose (FDG) and fluoroerythronitroimidazole (FETNIM) in a murine sarcoma model. ICR mice were xenografted with sarcoma 180 cell line and tumors were allowed to grow to a weight of 0.26-5.82 grams. 18F-FDG and 18F-FETNIM were injected intravenously in separate groups of mice, and after 1 hr, the tumors were excised and radiotracer uptake was measured. In another group of mice tumors were autoradiographically analyzed and subjected to H & E staining. In both the FDG and FETNIM group, per-gram radiotracer uptake by a tumor was inversely proportional to tumor weight. 18F-FETNIM correlated more (r = -0.593, p < 0.05) than 18F-FDG (r = -0.447, p < 0.05). Autoradiographic studies revealed that FDG accumulated in viable tumor areas, whereas FETNIM accumulated in both viable and partially necrotic areas. In the case of 18F-FETNIM, a direct correlation between tumor weight and the no-uptake-area to total-tumor-area was demonstrated. We concluded that increased tumor size is associated with decreased uptake of 18F-FDG and FETNIM, though this depends on the type of radiotracers and distribution of necrosis.


Subject(s)
Fluorine Radioisotopes , Fluorodeoxyglucose F18 , Nitroimidazoles , Sarcoma 180/diagnostic imaging , Sarcoma 180/pathology , Animals , Autoradiography , Male , Mice , Mice, Inbred ICR , Necrosis , Tomography, Emission-Computed
20.
J Nucl Med ; 40(2): 339-46, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10025844

ABSTRACT

UNLABELLED: [18F]Fluorodeoxyglucose ([18F]FDG), a glucose analogue, has been widely used for tumor imaging. To investigate the mechanisms related to [18F]FDG uptake by tumors, an experiment involving nude mice was performed. METHODS: Human colon cancer cell lines SNU-C2A, SNU-C4 and SNU-C5 were transplanted to nude mice. Using immunohistochemical staining and Western blot, the expression of glucose transporter (Glut) isoforms (Glut-1 through -5) in xenografted tumors was analyzed. For the analysis of messenger ribonucleic acid (mRNA) expression, reverse-transcription polymerase chain reaction and Northern blot were used and the enzyme activity of hexokinase in cancer tissues was measured by continuous spectrophotometric rate determination. RESULTS: [18F]FDG uptake in SNU-C4 and SNU-C5 cells was higher than in normal colon cells. Among these cells and xenografted tumors, SNU-C5 showed the highest level of [18F]FDG uptake, followed by SNU-C4 and SNU-C2A. An immunostaining experiment showed intense staining of Glut-1 in SNU-C5 tumors but somewhat faint staining in SNU-C4. SNU-C5 tumors also showed positive staining with Glut-3, although this was not the case with SNU-C2A and SNU-C4. Western blot analysis showed the expression of Glut-1 and Glut-3 in all tumors. Experiments involving Northern blot analysis and reverse-transcription polymerase chain reaction confirmed the overexpression of Glut-1 mRNA in all tumors, with the highest level in SNU-C5. The level of Glut-3 mRNA was also elevated in SNU-C5 tumors but not in SNU-C2A and SNU-C4. The enzyme activity of hexokinase did not vary among different tumors. CONCLUSION: Gluts, especially Glut-1, are responsible for [18F]FDG uptake in a nude mouse model of colon cancer rather than hexokinase activity. Increased numbers of glucose transporters at the plasma membrane of cancer cells is attributed to an increased level of transcripts of glucose transporter genes and may be a cause of increased [18F]FDG uptake, at least in colon cancer tumors.


Subject(s)
Colonic Neoplasms/metabolism , Fluorodeoxyglucose F18/pharmacokinetics , Radiopharmaceuticals/pharmacokinetics , Animals , Blotting, Northern , Blotting, Western , Colonic Neoplasms/diagnostic imaging , Hexokinase/analysis , Humans , Immunohistochemistry , Male , Mice , Mice, Nude , Monosaccharide Transport Proteins/analysis , Monosaccharide Transport Proteins/genetics , Neoplasm Transplantation , Polymerase Chain Reaction , RNA, Messenger/analysis , Radionuclide Imaging , Transplantation, Heterologous , Tumor Cells, Cultured
SELECTION OF CITATIONS
SEARCH DETAIL
...