PubMed Health⌕ Search

Biomedical subjects

J J Min

Publications and source records attributed to J J Min.

8 recordsLinked to original sources

Gene therapy progress and prospects: noninvasive imaging of gene therapy in living subjects.

Recent progress in the development of noninvasive imaging technologies should allow molecular imaging to play a major role in the field of gene therapy. These tools have recently been validated in gene therapy models for continuous quantitative monitoring of the location(s), magnitude, and time variation of gene delivery and/or expression. This article reviews the use of radionuclide, magnetic resonance, and optical imaging technologies, as they have been used in imaging gene delivery and gene expression for gene therapy applications. The studies published to date lend support that noninvasive imaging tools will help to accelerate preclinical model validation, as well as allow for clinical monitoring of human gene therapy.

Cardiovascular Diseases↗

Focal pulmonary uptake during Tc-99m myocardial perfusion SPECT imaging.

PURPOSE: To evaluate the incidence and origin of abnormal focal pulmonary uptake during myocardial perfusion SPECT imaging (MSPECT). METHODS: For evaluation of chest pain, 790 men and 581 women (mean age, 56 +/- 13 years) underwent MSPECT. All of them received adenosine for pharmacologic stress and Tc-99m tetrofosmin (TF, n = 817) or Tc-99m sestamibi (MIBI, n = 554) for myocardial perfusion imaging. RESULTS: Review of chest radiography with or without computed tomography revealed 111 (8.1%) focal pulmonary diseases. Among them, 38 (34.2%) showed focal pulmonary uptake (TF, 22; MIBI, 16); 27 (30.7%) of 88 showed previous pulmonary tuberculosis; 2 of 10 (20%) benign pulmonary nodules; 4 of 5 (80%) metastatic lung cancers; 2 of 4 (50%) primary lung cancers; and 3 of 4 (75%) pneumonias. No difference in uptake was noted for the two imaging agents. Intensity of uptake did not vary with origin of the uptake. Focal abnormal pulmonary uptake was found in 2.8% of patients undergoing MSPECT and in 34.2% of patients in whom radiological examinations showed regional pulmonary disease. In patients with abnormal pulmonary uptake on MSPECT, 16% had a malignant lesion, whereas 75% of patients with a pulmonary nodule shown on radiography and focal pulmonary uptake on MSPECT had a malignant lesion. CONCLUSIONS: Although the incidence of abnormal pulmonary uptake during MSPECT was very low, the incidence of malignant lesions in the patients with nodular pulmonary uptake was relatively high.

Adenosine↗

Relationship between expression of the sodium/iodide symporter and 131I uptake in recurrent lesions of differentiated thyroid carcinoma.

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.

Adenocarcinoma, Follicular↗

Dipyridamole modulated Tc-99m sestamibi lung SPECT in small cell lung cancer.

PURPOSE: In this study, the authors wanted to determine whether dipyridamole-modulated MIBI (dipyridamole-MIBI) could enhance the prediction of the response to chemotherapy in patients with small cell lung cancer. METHODS: Twenty-seven patients with biopsy-proved small cell lung cancer (25 men, 2 women; mean age, 61 +/- 7 years) underwent dipyridamole-MIBI SPECT 3 to 7 days before starting chemotherapy (80 mg/m2 etoposide and 80 mg/m2 cisplatin every 3 or 4 weeks for at least two cycles). Tomographic images before and after dipyridamole (0.84 mg/kg) were acquired 1 hour after injection of 370 (10 mCi) and 1,110 (30 mCi) MBq MIBI, respectively. The response to chemotherapy was grouped as specified as complete response (CR), partial (PR), no change (NC), or progressive disease (PD), according to the change in tumor size on chest roentgenography and CT. Patients showing CR and PR were classified as responders, and those who showed NC and PD were considered nonresponders. RESULTS: Among the 27 patients, 22 were responders (3 CR, 19 PR) and 5 were nonresponders (3 NC, 2 PD). The tumor-to-normal lung ratio (T:NL) of responders was significantly higher than that of nonresponders. The diagnostic accuracy of the T:NL ratio to differentiate responders and nonresponders was 33.3%, with a cutoff value of 2.5, which was significantly improved to 77.8% when an increased T:NL ratio after dipyridamole was assigned to a nonresponder. Furthermore, all patients with CR showed diminished T:NL ratios after dipyridamole, and all patients with NR showed an increased T:NL ratio after dipyridamole. CONCLUSION: Dipyridamole-MIBI SPECT could enhance the prediction of response to chemotherapy in patients with small cell lung cancer.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Technetium-99m-MIBI uptake in small cell lung cancer.

UNLABELLED: Patients with small cell lung cancer (SCLC) often fail to respond to chemotherapy due to multidrug resistance (MDR). Technetium-99m-MIBI was reported to be a suitable transport substrate of P-glycoprotein, which is a cytoplasmic membrane protein encoded by the MDR gene. The purpose of this study was to evaluate whether or not the degree of MIBI uptake in SCLC or its retention on delayed imaging correlated with response to chemotherapy. METHODS: Twenty-five patients (19 men, 6 women; mean age 59 +/- 10 yr) with biopsy-proven SCLC had MIBI SPECT 3-7 days before starting chemotherapy. Imaging was acquired 1 and 4 hr after injection of 740 MBq MIBI using a single-head rotating gamma camera. Tumor-to-normal lung uptake ratio (T/NL) was measured. Percent retention (%R) was measured as: %R = 100 x (T/NL at 4 hr)/(T/NL at 1 hr). All patients received VAP chemotherapy (VP-16 100 mg/m2, adriamycin 40 mg/m2, cisplatin 25 mg/m2) every 4 wk for at least three times. Response to chemotherapy was grouped as complete remission, partial remission and no remission according to the change of tumor size on chest radiograph and CT images. Differences in T/NL and %R among the three groups were analyzed using ANOVA. RESULTS: T/NL of patients with complete remission (n = 7) and partial remission (n = 10) were significantly higher than that of no remission (n = 8) in 1 hr and 4 hr. T/NL at 1 hr in three groups were 2.75 +/- 0.78, 2.35 +/- 0.31 and 1.65 +/- 0.36, respectively. T/NL at 4 hr in three groups was 2.61 +/- 0.94, 2.48 +/- 0.50 and 1.66 +/- 0.42, respectively. However, %R was not different among three groups. Percent retention in three groups was 109.40 +/- 22.10, 96.71 +/- 14.25 and 103.59 +/- 28.43, respectively. CONCLUSION: SCLC with a higher MIBI uptake was more likely to respond to chemotherapy than that with a lower uptake. However, there was a considerable overlap of MIBI uptake among subjects. No significant correlation between the MIBI retention between 1 hr and 4 hr, and the response to chemotherapy was noted.

Antineoplastic Combined Chemotherapy Protocols↗

Two-minute miniprep method for plasmid DNA isolation.

An extremely rapid method, INSTA-PREP, has been developed to prepare plasmid DNA from 1 to 3 mL miniprep Escherichia coli bacterial cultures. Direct extraction of plasmid DNA from E. coli bacterial cells is achieved by a two-phase solution consisting of phenol-chloroform-isoamyl alcohol and water or buffer with efficient separation of the phases by centrifugation in the presence of the INSTA-PREP gel barrier material. Processing time, from E. coli culture to usable plasmid DNA, is two minutes or less per sample. Supercoiled plasmid DNA yields ranged from 3 to 10 micrograms per mL of culture depending on plasmid copy number. Plasmid DNAs prepared by INSTA-PREP were analyzed and are suitable for use in molecular biology procedures including restriction digestion, ligation with T4 DNA ligase, bacterial transformation, PCR, cultured cell transfection and T7 DNA polymerase or thermostable DNA polymerase-mediated dideoxynucleotide sequencing.

Animals↗

Characterization of a novel NTP-dependent 3' exoribonuclease from yeast mitochondria.

We have purified and characterized a novel exoribonuclease that was isolated from the mitochondria of Saccharomyces cerevisiae. The enzyme degraded RNA in a 3' to 5' direction and was dependent on nucleotide triphosphates for activity. All eight of the standard ribo- and deoxyribonucleotide triphosphates supported activity with an apparent Km ranging from 20 to 90 uM. The enzyme also exhibited an RNA-dependent ATPase activity. Evidence suggests that in vivo the enzyme may associate with mitochondrial factors which can alleviate the dependence on nucleotide triphosphates for enzymatic activity. A model is discussed for the role of the enzyme in regulating the turnover of mitochondrial RNAs.

Adenosine Triphosphatases↗