Noninvasive imaging of c(RGD)2 -9R as a potential delivery carrier for transfection of siRNA in malignant tumors.

The purpose of our study was to develop and evaluate a novel integrin αv ß3 -specific delivery carrier for transfection of siRNA in malignant tumors. We adopted arginine-glycine-aspartate (RGD) motif as a tissue target for specific recognition of integrin αν ß3 . A chimaeric peptide was synthesized by adding nonamer arginine residues (9-arginine [9R]) at the carboxy terminus of cyclic-RGD dimer, designated as c(RGD)2 -9R, to enable small interfering RNA (siRNA) binding. To test the applicability of the delivery carrier in vivo, c(RGD)2 -9R was labeled with radionuclide of technetium-99m. Biodistribution and γ-camera imaging studies were performed in HepG2 xenograft-bearing nude mice. As results, an optimal 10:1 molar ratio of 99m Tc-c(RGD)2 -9R to siRNA was indicated by the electrophoresis on agarose gels. 99m Tc-c(RGD)2 -9R/siRNA remained stable under a set of conditions in vitro. For in vivo study, tumor radioactivity uptake of 99m Tc-c(RGD)2 -9R/siRNA in nude mice bearing HepG2 xenografts was significantly higher than that of control probe (P < .05). The xenografts were clearly visualized at 4 hours till 6 hours noninvasively after intravenous injection of 99m Tc-c(RGD)2 -9R/siRNA, while the xenografts were not visualized at any time after injection of control probe. It was concluded that c(RGD)2 -9R could be an effective siRNA delivery carrier. Technetium-99m radiolabeled-delivery carrier represents a potential imaging strategy for RNAi-based therapy.

[(131)I labeling and bioactivity evaluation of a novel RGD dimer targeted to integrin αvß3 receptor].

OBJECTIVE: To study the (131)I labeling, tumor targeting property, biodistrubution and imaging of a novel disulfide bridged Arg-Gly-Asp (RGD) peptide dimer and investigate its possibility for tumor angiogenesis imaging. METHODS: A disulfide bridged cRGD peptide dimer [c(RGD)2] was designed according to the published RESULTS of structure-activity relationship study of c(RGDfV) and modified with hydrophilic amino acid. The affinity of the peptide to αvß3 receptor was determined by binding assay. The peptide was labeled with (131)I by ChT method. The stability and lg n-octanol-water partition coefficient of the labeled peptide were tested. The biodistribution, inhibition with unlabeled peptide and imaging were performed by injecting the labeled peptide into the mice bearing meloma B16. RESULTS: The (131)I labeling efficiency and radiochemical purity were (76.35 ± 2.33)% and (95.20 ± 3.25)%, respectively. Ka was (0.137 ± 0.057) × 10(9) /mol/L, and lgPo(ctanol/water) was-1.628. The tumor uptake of the labeled peptide at 1 h, 3 h, 5 h and 24 h were (0.67 ± 0.13)%ID/g, (0.42 ± 0.08)%ID/g, (0.51± 0.11)%ID/g and (0.18 ± 0.02)%ID/g, respectively. The tumor clearance was low, so the T/NT increased with time. The T/M and T/B were 4.42 ± 1.70 and 2.27 ± 0.45, respectively, 24 h post-injection. The hepatic uptake of the labeled peptide was low. The tumor-to-liver ratio was 2.10 ± 0.60 at 1 h post-injection, coinjection of c(RGD)2 with (131)I-c(RGD)2 resulted in a significant decrease in tumor uptake. In total body images, only kidneys were distinctive whereas tumor was clear in chest images 3 h post-injection. CONCLUSION: c(RGD)2 can be successfully labeled with (131)I by ChT method. The labeled peptide can be specifically combined with tumor, which suggests its possibility in tumor angiogenesis imaging. Its low liver uptake provides an advantage for tumor imaging.

Synthesis and evaluation of novel organogermanium sesquioxides as antitumor agents.

Five new organogermanium sesquioxides have been synthesized and characterized by elemental analysis and IR spectra. All the compounds were tested for antitumor activities against KB, HCT, and Bel cells in vitro. Compound 5 (gamma-thiocarbamido propyl germanium sesquioxide) showed excellent antitumor activity, and its inhibition yield to KB, HCT, and Bel cells was 92.9%, 84.9%, and 70.9%, respectively. A rapid method was described for the labeling compound 5 with (99m)Tc, and the optimum labeling conditions were investigated. The labeling yield is above 90% in pH 7.0, 20 degrees C, reaction time greater than 10 minutes, 1 mg of compound 5, and 0.075 approximately 0.1 mg of SnCl(2). The biodistribution of (99m)Tc labeled compound 5 in nude mice bearing human colonic xenografts was studied. The result showed that the tumor uptakes were 0.73, 0.97, 0.87, and 0.62 ID%/g at 1-hour, 3-hour, 6-hour, and 20-hour postinjection, respectively. T/NT (the uptake ratio for per gram of tumor over normal tissues) was 18.3 for tumor versus brain and 5.81 for tumor versus muscle at 20-hour postinjection. The tumor clearance was slow. The results showed that compound 5 may be developed to be a suitable cancer therapeutic agent.

[Clinical observation of rapid massage at Shuidao (ST 28) to prevent postpartum urinary retention].

OBJECTIVE: To explore the clinical effect of rapid massage at Shuidao (ST 28) to prevent puerpera from postpartum urinary retention. METHODS: A total of 200 puerpera giving birth through vagina were enrolled and divided into an observation group and a control group according to the random number table method, 100 cases in each group. In the observation group, rapid massage at Shuidao (ST 28) was applied. In the control group,there was no intervention and urinated naturally. The traditional Chinese medicine syndrome scale was used to evaluate poor sense of urination, and record puerpera with or without postpartum urinary retention, the poor sense of first urination, the first time of urination, the amount of first urination and postpartum hemorrhage. RESULTS: The poor sense of first urination in the observation group was significantly lower than that in the control (P<0.001), the first time of urination in the observation group was significantly earlier than that in the control group (P<0.001), the amount of first urination in the observation group was significantly more than that in the control group (P<0.001), the observation group was superior to the control group to prevent postpartum urinary retention (P<0.05). CONCLUSION: Rapid massage at Shuidao (ST 28) can reduce the poor sense of first urination, significantly advance the time of spontaneous urination, significantly increase the amount of first urination and effectively prevent postpartum urinary retention.

Noninvasive imaging of human telomerase reverse transcriptase (hTERT) messenger RNA with 99mTc-radiolabeled antisense probes in malignant tumors.

UNLABELLED: The expression of human telomerase reverse transcriptase (hTERT) is present in most malignant cells (>85%) but is undetectable in most normal somatic cells. Visualization of hTERT expression using radionuclide targeting can provide important diagnostic information in malignant tumors. The overall aim of this study was to evaluate whether (99m)Tc-radiolabeled antisense oligonucleotide (ASON) targeting hTERT messenger RNA (mRNA) can be used for imaging of hTERT expression in vivo. METHODS: One 18-mer antisense or sense uniformly phosphorothioate-modified oligonucleotide targeting hTERT mRNA was radiolabeled with (99m)Tc through the bifunctional chelator N-hydroxysuccinimidyl derivative of S-acetylmercaptoacetyltriglycine (S-acetyl NHS-MAG3). Then the radiolabeled probe was characterized in vitro. Reverse transcription-polymerase chain reaction (RT-PCR) was performed to assay the mRNA level after proliferating cells had been incubated with the antisense and sense probes. (99m)Tc-MAG3-ASON or (99m)Tc-MAG3-SON was injected intravenously in mammary tumor-bearing BALB/c nude mice. Biodistribution and in vivo imaging was performed periodically. All data were analyzed by statistical software. RESULTS: The labeling efficiencies of (99m)Tc-MAG3-ASON/SON reached 76% +/- 5% (n = 5) within 15-30 min at room temperature, the specific activity was up to 1,850 kBq/mug, and the radiochemical purity was >96% after purification. (99m)Tc-MAG3-ASON showed complete stability at room temperature and in fresh 37 degrees C human serum. In comparison with (99m)Tc-MAG3-SON, (99m)Tc-MAG3-ASON preserved the capacity to bind living hTERT-expressing cells specifically and to inhibit the expression of hTERT mRNA significantly as well as ASON. In nude mice bearing hTERT-expressing MCF-7 xenografts, tumor radioactivity uptake of (99m)Tc-MAG3-ASON after injection was significantly higher than that of (99m)Tc-MAG3-SON after injection (P < 0.05). The hTERT-expressing xenografts were clearly imaged at 4-8 h noninvasively after injection of (99m)Tc-MAG3-ASON, whereas the xenografts were not imaged at any time after injection of (99m)Tc-MAG3-SON. CONCLUSION: This in vivo study provides evidence that (99m)Tc-MAG3-ASON targeting hTERT mRNA can be used as a potential candidate for visualization of hTERT expression in carcinomas.

[Study of clinical value of dual-phase imaging using single photon emission computed tomography with coincidence detection for differentiating benign from malignant lesions].

OBJECTIVE: To investigate the clinical value of dual-phase imaging of 18F-fluoro-2-deoxy-D-glucose (18F-FDG) using single photon emission computed tomography with coincidence detection (SPECT with coincidence) for differentiating benign and malignant lesions. METHODS: Thirty patients with unknown lesions from June 2003 to March 2004 in our hospital were enrolled in this study. All patients underwent dual-phase imaging of 18F-FDG SPECT with coincidence. The early images were obtained 60 min post injection. And the patients were divided into 2 groups, one receiving delayed scans at 210 min after 18F-FDG injection and the other at 270 min. Lesion status was determined by pathologic findings or by clinical follow-up. RESULTS: Forty-eight lesions (30 malignant and 18 benign lesions verified by pathologic findings or clinical follow-up) of 30 patients were detected by dual-phase imaging, in which there were 29 true positive results, 15 true negative, 3 false positive and 1 false negative. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of dual-phase imaging were 96.7%, 83.3%, 91.6%, 90.6%, and 93.8%, respectively. Those of early imaging and CT were 93.3%, 72.2%, 85.4%, 84.8%, 86.7% and 76.9%, 57.1%, 70.0%, 76.9%, 57.1%, respectively. The T/NT of all malignant lesions (except 1 false negative case) in delayed imaging were significantly increased (t=-3.071, P<0.01). However, there were no statistical differences in the T/NT of benign lesions (t=0.398, P=0.695) between early and delayed imagings. CONCLUSION: Dual-phase imaging of FDG SPECT with coincidence provides benefit for differentiating benign and malignant lesions.

[Use of fiber-reinforced chemical curing resin to close the inter-proximate space of the posterior teeth].

PURPOSE: To investigate the clinical efficacy of using fiber-reinforced chemical curing resin to close the inter-proximate space of the posterior teeth and block the food impaction. METHODS: One hundred and sixty-two patients with food impaction of posterior teeth were selected in this study. The total number of the food impaction was 170. They were divided into narrow-gap group and wide-gap group according to the damage of the inter-proximate space. Jingjin enamel adhesive reinforced polyethylene fiber ribbon was used in both group to close the inter-proximate space. The patients were reviewed at 6-month and 1-year. After the second follow-up examination, 161 restorations of 154 patients were included in this study. The differences between the 2 groups were analyzed by Chi-square test with SPSS 13.0 software package. RESULTS: Statistical differences were found in the retention rate of the restorations at 6-month between the 2 groups (P<0.05). The retention rate in the narrow-gap group was significantly lower than that in the wide-gap group. However, there was no significant difference between the 2 groups at 1-year. There was no significant difference in integrality between the 2 groups at 6-month and 1-year. CONCLUSIONS: The use of fiber-rein forced chemical curing resin to close the inter-proximate space of the posterior teeth and block the food impaction is more suitable for patients with clinical crown elongation, gingival recession, alveolar bone loss and the tissue damages in the inter-proximate space, which will cause food impaction.

Enhanced EJ Cell Killing of (125)I Radiation by Combining with Cytosine Deaminase Gene Therapy Regulated by Synthetic Radio-Responsive Promoter.

AIM: To investigate the enhancing effect of radionuclide therapy by the therapeutic gene placed under the control of radio-responsive promoter. METHODS: The recombinant lentivirus E8-codA-GFP, including a synthetic radiation-sensitive promoter E8, cytosine deaminase (CD) gene, and green fluorescent protein gene, was constructed. The gene expression activated by (125)I radiation was assessed by observation of green fluorescence. The ability of converting 5-fluorocytosine (5-FC) to 5-fluorourial (5-FU) by CD enzyme was assessed by high-performance liquid chromatography. The viability of the infected cells exposed to (125)I in the presence of 5-FC was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and the infected cells exposed to (125)I alone served as negative control and 5-FU as positive control. RESULTS: The recombinant lentiviral vector was constructed successfully. On exposure of infected cells to (125)I, green fluorescence can be observed and 5-FU can be detected. MTT assay showed that the survival rate for infected cells treated with (125)I was lower compared with the (125)I control group, but higher than the positive control group. CONCLUSION: The synthetic promoter E8 can induce the expression of downstream CD gene under (125)I radiation, and the tumor killing effect of (125)I can be enhanced by combining CD gene therapy with radiosensitive promoter.

[Study on biodistribution and imaging of radioiodinated antisense oligonucleotides in nude mice bearing human lymphoma].

OBJECTIVE: To investigate the possibility of using radioiodine labeled framework region (FR) antisense oligonucleotides (ASONs) as an imaging agent or antisense therapeutic radiopharmaceutical in lymphoma. METHODS: A 18-mer partial phosphorothioate oligonucleotide sequence was synthesized and grafted in 5' with a tyramine group which was further radioiodinated. Radioiodination of the tyramine derivatized oligonucleotides was performed using the chloramine T method. (1) Normal CD-1 mice were injected via a tail vein with 148 kBq (125)I-FR-ASON (2-3 microg). Animals were sacrificed at the end of 1, 2, 4 and 24 h, and tissue samples were studied.(2) Liposome-mediated 3.33 MBq (131)I-FR-ASON (7-9 microg) were injected intratumorally into tumor-bearing BALB/c mice (6 weeks after inoculation of 107 Namalwa cells) meanwhile liposome-mediated (131)I labeled sense oligonucleotides served as controls. Biodistribution was monitored by sequential scintigraphy and organ radioactivity measurement 24 h after injection. Percentage of the injected dose per gram of tumor and tumor/non-tumor tissue ratios (T/NT) were calculated for each group of mice and the difference between two groups was assessed. RESULTS: The 5' tyramine group allowed specific and stable radiolabeling of the ASON with radioiodine. The radioactivity reached its peak 1 h after injection, and then decreased rapidly in normal mice after intravenous administration of (125)I-FR-ASON. The liver, stomach and intestine played an important role in biodistribution and radioactivity counts were low in bone, brain and blood. When (131)I-FR-ASON was injected intratumorally into mice grafted with Namalwa cell line, images showed the tracer accumulated in the tumor. Immediately after intratumoral administration, only the tumor was visible. Scintiscans performed at the end of 1 and 2 h showed elimination of the tracer from the tumor to the abdomen and at the end of 24 h the tumor was clearly seen. Percentage of the injected dose per gram of tumor and T/NT ratios for the sense group (control) were significantly lower than those of the antisense group. CONCLUSION: Radiolabeled Ig FR ASON showed high specificity in V1 family B-cell lymphoma, which should be further investigated for nuclear medicine imaging application and radionuclide antisense therapy.

[Measurement of glomerular filtration rate with renal dynamic imaging: comparison with two-sample method].

OBJECTIVE: To compare the estimation of glomerular filtration rate (GFR) by renal dynamic imaging with that estimated by two-sample method and evaluate the reliability of measurement of GFR by renal dynamic imaging. METHODS: The study was performed in 54 patients (33 males and 21 females; aged 15 to 82 years) with primary or secondary chronic nephrosis. The patients were intravenously bolus injected with 185 MBq /1mL of (99)Tc(m)-DTPA 20 min after drinking 300 mL of water. Renal dynamic imaging was performed and the image was processed according to standard procedure (Gates' method) to obtain GFR. 3 mL of blood was withdrawn 2 h and 4 h postinjection, respectively, and radioactivity of 1mL plasma was measured. GFR was calculated by the formula of two-sample method. The correlation of GFRs measured by renal dynamic imaging and by two-sample method was analyzed using regression analysis. The correlations of GFRs determined by the two methods with urea and creatinine were also measured. RESULTS: The GFR measured by renal dynamic imaging was slightly lower than that measured by two-sample method. Excellent correlation was obtained by two methods with r= 0.881 5 and P<0.01. The linear regression equation was GFR (renal dynamic imaging method)=0.661 4GFR (two-sample method) +21.89. The related lines of GFRs measured by the two methods with urea or creatinine were similar, which indicated the two methods were similar in identifying the changes in renal function. GFRs measured by the two methods showed good agreement for most of patients except three patients who were too thin or too fat. CONCLUSION: Generally, GFR obtained by renal dynamic imaging is reliable for identifying the changes in renal function and correlated well with GFR obtained by two-sample method. But great error may be obtained with specific individuals, such as too thin or too fat subjects.

Expression of transforming growth factor-beta 1 and connective tissue growth factor in women with pelvic organ prolapse.

OBJECTIVE: To investigate the presence of transforming growth factor-beta 1 (TGF-ß1) and connective tissue growth factor (CTGF) in women with pelvic organ prolapse (POP). METHODS: This study was conducted from May to December 2009. Fifty patients with POP that underwent vaginal hysterectomy in the Department of Gynecology, Renmin Hospital of Wuhan University, Hubei, Wuhan, China were enrolled in this study. They were divided into: Group 1 (n=10); Group 2 (n=10); and Group 3 (n=10) according to Pelvic Organ Prolapse Quantitation (POP-Q). Meanwhile, 20 cases treated by vaginal hysterectomy for other benign gynecological diseases were selected as the control group. Immunohistochemical staining and Western blot were performed to detect the expression of TGF-ß1 and CTGF. RESULTS: Immunohistochemical staining of TGF-ß1 and CTGF were mainly expressed in the cytoplasm of fibroblast cells. The expression of TGF-ß1 and CTGF protein was significantly negatively correlated with POP-Q stage. There were significantly positive correlations between the expression of TGF-ß1 and CTGF protein. The expression of TGF-ß1 protein among the 3 POP groups were all significantly lower than that of the control group, while there was no significant differences in the expression of TGF-ß1 protein among the POP groups, excluding the comparison between Groups 1 and 3. The expression of CTGF protein in the 3 POP groups were all significantly lower than that of the control group, and significant differences were also detected among the 3 POP groups. CONCLUSION: In this study, we found that the TGF-ß1 and CTGF protein expression may be associated with POP, especially in POP-Q stages.

[Clinical observation of 45 cases with radicular cyst treated with non-surgical methods].

PURPOSE: To observe the clinical effect and the influential factors of non-surgical treatment of radicular cyst. METHODS: A total of 45 cases with radicular cyst were included from 2002 to 2008. They were treated by non-surgical treatment including decompression of cyst cavity or overfilling of the root canal. All the patients were examined at 3,6 months and 1,2,3 years after treatment. The therapeutic result was analyzed with SPSS15.0 software package for X(2) test. RESULTS: Of the 45 cases, 22 were cured at a follow-up period of 1-4 years, the cure rate was 48.89%. Seventeen cases were improved, the improvement rate 37.78%, and the total efficiency rate was 86.67%. Six cases failed to the treatment, and the failure rate was 13.33%. CONCLUSIONS: With decompression of cyst cavities or overfilling of the root canals, non-surgical treatment of radicular cyst is a simple, economical, safe, and effective treatment modality.

[Treatment of teeth with open canal system using mineral trioxide aggregate as apical barrier under the dental operating microscope].

PURPOSE: To evaluate the effect of closing root apex of permanent teeth with mineral trioxide aggregate to form barricade in root tip under the dental operating microscope. METHODS: 63 teeth treated in our department with open root apex and periapical periodontitis were selected, MTA was used to rigorously close the root apex under microscope, and thermoplastic gutta pertscha was used to fill dental root after formation of barricade in the root tip. All patients revisited regularly for clinical examinations after treatment. RESULTS: Among the 63 treated teeth, only one tooth (23) was insufficiently filled because of the long dental root and unclear field of vision under microscope, the remaining 62 teeth were filled adequately. The postoperative dental film showed 43 teeth were properly filled while 17 had a little over-filling. The patients were rechecked after three months, and the results showed that 2 patients underwent retro-filling because of fistula, 2 patients were lost during follow-up period, and the remaining patients reached the requirement for success including no sensitivity to percussion, improvement or disappearance of pathological changes around the root tip on dental film and regeneration of bone trabecula. The therapeutic effect was not influenced by minor over-filling. The overall success rate was 95%. CONCLUSION: The method of using mineral trioxide aggregate (MTA) to treat teeth with root apex open is accurate and convenient and the effect is pretty good.