OBJECTIVETo establish and evaluate a rabbit model of fecal incontinence.

METHODSTwelve normal adult male New Zealand rabbits were randomly divided into experimental group and control group. The nerve innervating the external anal sphincter, namely the fourth sacral nerve, was functionally located and selectively damaged with local injection of 50 g/L ropivacaine in the experimental group, and normal saline injection was administered in the control group. The changes in the resting anal pressure was examined before and after the surgery, and the electromyogram (EMG) of the external anal sphincter was recorded for comparison with the pathological changes of the fourth sacral nerve.

RESULTSCompared with the control group, the experimental group exhibited significantly decreased resting anal pressure after the surgery. The EMG of the experimental group showed abnormal nerve conduction velocity of the fourth sacral nerve, suggesting successful nerve block. Transmission electron microscope revealed irreversible pathological changes in the ultrastructure of the axons of the fourth sacral nerve.

CONCLUSIONThis method allows successful establishment of fecal incontinence in rabbits, which facilitates further in vivo study of artificial sphincters for treatment of anal incontinence.

Amides ; administration & dosage ; Anal Canal ; physiopathology ; Animals ; Disease Models, Animal ; Electromyography ; Fecal Incontinence ; Lumbosacral Plexus ; Male ; Nerve Block ; Rabbits ; Random Allocation

Aged ; External Fixators ; Female ; Follow-Up Studies ; Fractures, Bone ; complications ; physiopathology ; surgery ; therapy ; Humans ; Male ; Middle Aged ; Osteoporosis ; complications ; Tomography, X-Ray Computed ; Treatment Outcome

OBJECTIVETo investigate the selective killing of colorectal tumor cells by lentivirus-mediated double suicide gene under the regulation of KDR promoter.

METHODS293T packaging cells were transfected with the plasmid FGW-KDRP-CD/TK to obtain the infectious viruses. KDR-expressing LoVo cells and LS174T cells that did not produce KDR were transfected with the recombinant virus, and the transfection efficiency was evaluated by the fluorecence microscope. RT-PCR was employed to examine the expression of CDglyTK. After treatment of the cells with 5-FC and GCV, the killing effects on the two cell lines were evaluated.

RESULTSThe recombinant construct showed similar infection rate of the two cell lines. RT-PCR demonstrated that CDglyTK gene was expressed only in LoVo cells infected with FGW-KDRP-CD/TK but not in LS147T cells, and the sensitivity of the two cell lines to the prodrugs was significantly different (P<0.001). The killing effect of the double suicide gene was much stronger than that of single suicide gene administered (P<0.001).

CONCLUSIONThe double suicide gene driven by KDR promoter has specific killing effect on the KDR-expressing colorectal tumor cells.

Antimetabolites ; pharmacology ; Apoptosis ; drug effects ; Cell Line ; Cell Line, Tumor ; Colorectal Neoplasms ; genetics ; metabolism ; pathology ; Cytosine Deaminase ; genetics ; metabolism ; Flow Cytometry ; Flucytosine ; pharmacology ; Ganciclovir ; pharmacology ; Genes, Transgenic, Suicide ; genetics ; Genetic Vectors ; genetics ; Humans ; Lentivirus ; genetics ; Promoter Regions, Genetic ; genetics ; Recombinant Fusion Proteins ; genetics ; metabolism ; Thymidine Kinase ; genetics ; metabolism ; Transfection ; Vascular Endothelial Growth Factor Receptor-2 ; genetics

OBJECTIVETo study the selective cytotoxic effect of lentivirus-mediated double suicide gene (CD/TK) against human gastric carcinoma cells SGC-7901 in vitro.

METHODSSGC-7901 cells were infected with FGW-KDRP-CD/TK vector and the infection efficiency was observed under a fluorescence microscope. The morphological changes of the infected cells were observed by Giemsa staining. Flow cytometry (FCM) was employed for cell cycle analysis, and the expression of CD/TK was detected by RT-PCR. The infected cells were then treated with the prodrugs ganciclovir (GCV) and/or 5-fluorocytosine (5-FC) at different concentrations, and the cytotoxic effects were evaluated using MTT method.

RESULTSThe infection efficiency of the lentiviral vector in SGC-7901 cells increased with the titer of the virus, which produced no significant effect on the cancer cell morphology in vitro or on the percentages of G0-G1, G2-M and S phase cells (P>0.05). RT-PCR demonstrated the expression of CD/TK gene in SGC-7901 cells infected by FGW-KDRP-CD/TK. The infected cells were highly sensitive to the prodrugs with a dose-dependent cytotoxic effect within a specific concentration range of the drugs, whereas the non-infected cells were not sensitive to the prodrugs. Combined use of the two prodrugs produced an obviously stronger inhibitory effect than either of the them (P<0.05). When combined, GCV and 5-FC at the concentration of 0.1+40, 1+80, 10+160, and 100+320 mg/L demonstrated a synergetic effect with a CDI<1.

CONCLUSIONLentivirus-mediated CD/TK fusion gene system can selectively kill gastric cancer cells, and the two prodrugs show a synergistic cytotoxic effect.

Adenocarcinoma ; genetics ; pathology ; Cell Line, Tumor ; Cytosine Deaminase ; biosynthesis ; genetics ; Cytotoxins ; pharmacology ; Genes, Transgenic, Suicide ; genetics ; Genetic Therapy ; Genetic Vectors ; genetics ; Humans ; Lentivirus ; genetics ; metabolism ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; pharmacology ; Stomach Neoplasms ; genetics ; pathology ; Thymidine Kinase ; biosynthesis ; genetics ; Vascular Endothelial Growth Factor Receptor-2 ; genetics ; metabolism

OBJECTIVETo investigate the clinical value of 64-slice computed tomographic angiography (CTA)-based virtual colonoscopy in the diagnosis of colonic tumors.

METHODSPhilips/Brilliance 64 CT volumetric scanning was performed in 8 patients with colonic cancer and 2 with colonic polypi identified by postoperative pathological examination. Mimics software was used for surface rendering of the intestine with the Marching Cubes algorithm for 3-dimensional (3D) virtual endoscope (VE) reconstruction and CTA-based 3D reconstruction of the large intestine and the surrounding structures. The location, volume and appearance of the lesions displayed by the virtual techniques were compared with the pathological results.

RESULTSThe 3D reconstruction was successfully completed in all the 10 cases, and the imaging diagnoses showed a total match with the pathological diagnoses. No significant differences were found between virtual endoscopy and CT virtual endoscopy. Virtual colonoscopy combined with digital model reconstruction provided valuable information for accurate identification of the position of the lesions and the complex adjacent anatomical structures.

CONCLUSIONVirtual colonoscopy based on 64-slice CTA, when combined with 3D reconstruction technique, allows accurate display of the colonic lesions and potential metastasis, which can be crucial for clinical staging and surgical planning of colonic cancer.

Adult ; Angiography ; methods ; Colorectal Neoplasms ; diagnostic imaging ; therapy ; Female ; Humans ; Image Processing, Computer-Assisted ; methods ; Imaging, Three-Dimensional ; Male ; Middle Aged ; Tomography, Spiral Computed

OBJECTIVETo study the inhibitory effect of adenovirus-mediated fusion gene system driven by KDR promoter on the proliferation of human gastric adneocarcinoma SCG7901 cells and observe the bystander effect in vitro.

METHODSSCG7901, ECV304 and HepG2 cells were infected with Ad-KDR-CDglyTK and Ad-CMV-CDglyTK at a multiplicity of infection (MOI) of 100, and the infection efficiency and the mRNA expressions of the transferred fusion gene were investigated. GCV and/or 5-FC at different concentrations were added into the culture medium of the infected cells to observe the targeted antitumor effect and bystander effect of CDglyTK suicide gene driven by KDR promoter.

RESULTSWith the MOI of the adenovirus of 100, the fluorescence emitted by green fluorescent protein (GFP) was observed in 95% of the infected SCG7901, ECV304 and HepG2 cells. All the cells infected by Ad-CMV-CDglyTK and SCG7901 and ECV304 cells infected by Ad-KDR-CDglyTK were highly sensitive to the prodrugs. In comparison, HepG2 cells infected with Ad-KDR-CDglyTK did not show much sensitivity to the two prodrugs. Following treatment with the prodrugs at the same concentration, the infected SCG7901 and ECV304 cells exhibited gradually lowered survival rates as the culture time was prolonged, whereas the transgenic HepG2 cells showed no such time-dependent changes. When the non-infected cells were cocultured with the transgenic cells, the bystander effect of CDglyTK gene was observed, which increased with the ratio of the transgenic cells. In these mixed cell culture systems, GCV and 5-FC showed obvious synergetic effect in suppressing the cell survival.

CONCLUSIONThe CDglyTK fusion gene system driven by KDR promoter can inhibit the proliferation of SCG7901 and ECV304 cells with obvious bystander effect in vitro. The combination of the prodrugs produces obvious synergetic effect against the cell survival.

Adenocarcinoma ; genetics ; pathology ; therapy ; Adenoviridae ; genetics ; metabolism ; Cell Line, Tumor ; Cytosine Deaminase ; biosynthesis ; genetics ; Genes, Transgenic, Suicide ; genetics ; Genetic Therapy ; Genetic Vectors ; genetics ; Humans ; Promoter Regions, Genetic ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; Stomach Neoplasms ; genetics ; pathology ; therapy ; Thymidine Kinase ; biosynthesis ; genetics ; Vascular Endothelial Growth Factor Receptor-2 ; genetics ; metabolism

OBJECTIVETo investigate the effect of 5-aminolevulinic acid (ALA)-mediated photodynamic therapy (PDT) on human gastric cancer xenografts in vivo and to explore its potential tumoricidal mechanism.

METHODSCultured MGC-803 human gastric cancer cells were injected below the skins of the nude mice to develop the tumor model. The tumor-bearing nude mice were examined under the Leica LT-9 MACIMSYSPULS to detect the fluorescence. The tumor volume of day 1, 3, 7, 14, 21 after treatment were measured, and its histological changes were also studied. The tissues of the tumors in nude mice of the control group, light group, 5-ALA group and PDT group were examined with the electron microscope and apoptosis was detected by TUNEL assay.

RESULTSThe tumor model was successfully developed. The tumor in the nude mice emitted the red fluorescence under the Leica LT-9 MACIMSYSPULS. The tumor volumes were (0.189+/-0.010) cm(3), (0.183+/-0.011) cm(3), (0.185+/-0.019)cm(3), (0.182+/-0.015)cm(3) for the control group, light group, 5-ALA group, PDT group, respectively at day 1 after treatment, while at day 3, (0.294+/-0.010) cm(3), (0.280+/-0.013) cm(3), (0.278+/-0.016) cm(3), (0.183+/-0.014) cm(3); at day 7, (0.409+/-0.016) cm(3), (0.411+/-0.009) cm(3), (0.407+/-0.015) cm(3), (0.221+/-0.008) cm(3); at day 14, (0.970+/-0.055) cm(3), (0.976+/-0.054) cm(3), (0.981+/-0.032)cm(3), (0.318+/-0.005) cm(3); at day 21, (1.495+/-0.059) cm(3), (1.513+/-0.057) cm(3), (1.524+/-0.063) cm(3), (0.446+/-0.042) cm(3) (F=1003.086, P=0.000). The histology demonstrated that most tumor blood vessels were congested and necrosis developed after PDT while not in the control group, light group and 5-ALA group. Necrosis and apoptosis were observed in the cells of the tumors of the PDT group examined by TUNEL and electron microscope while not in the cells of the tumors of the other groups.

CONCLUSIONS5-aminolevulinic acid-mediated photodynamic therapy (PDT) can induce injury to human gastric cancer xenografts and inhibit the tumor growth while light only and 5-ALA only can not. 5-aminolevulinic acid-mediated photodynamic therapy (ALA- PDT) appears to be a promising therapy for human gastric cancer, whose mechanism involves in the destruction of the tumors partly by apoptosis other than necrosis.

Aminolevulinic Acid ; therapeutic use ; Animals ; Cell Line, Tumor ; Female ; Humans ; Male ; Mice ; Mice, Nude ; Neoplasm Transplantation ; Neoplasms, Experimental ; Photochemotherapy ; Stomach Neoplasms ; therapy ; Xenograft Model Antitumor Assays

To improve the targeting of adenovirus vector for gene therapy, a fusion gene sCAR-EGF, in which epidermal growth factor gene was fused to the 3' end of extracellular Coxsackie virus-adenovirus receptor gene, was constructed and cloned into shuttle plasmid pDC315 to obtain a recombinant plasmid pDC315-sCAR-EGF. With the AdMax system, AD-293 cells were co-transfected with pDC315-sCAR-EGF and adenovirus genomic plasmid pBHGloxdeltaE13cre. Through high efficiency site specific recombination, a replication-defective adenovirus Ad5-CMV-sCAR-EGF was constructed. The recombinant adenovirus was analyzed by PCR and Western blotting, the results indicated that Ad5-CMV-sCAR-EGF contained the fusion gene sCAR-EGF, and the adenovirus infected cells was induced to produce and secrete the fusion protein into the supernatant. We have demonstrated that the fusion protein sCAR-EGF is helpful for elevating the infection efficiency of Ad5-CMV-luc with the reporter gene in vitro, which providing a new approach to the gene therapy for tumors overexpressing EGFR.
Adenoviridae ; genetics ; Cell Line ; Coxsackie and Adenovirus Receptor-Like Membrane Protein ; Enzyme-Linked Immunosorbent Assay ; Epidermal Growth Factor ; analysis ; genetics ; Genetic Therapy ; Humans ; Neoplasms ; therapy ; Polymerase Chain Reaction ; Receptors, Virus ; analysis ; genetics ; Recombinant Fusion Proteins ; biosynthesis

OBJECTIVETo study the effect of adenovirus (Ad)-mediated fusion gene system driven by KDR promoter on the proliferation of human stomach adneocarcinoma SCG7901.

METHODSThe KDR-expressing SCG7901 cells and HepG2 cells that did not express KDR were both transfected with AdEasy-KDR-CDglyTK followed by treatment with the prodrugs 5-FC and/or GCV at different concentrations. The killing effects of the transfection on the cells were evaluated.

RESULTSThe expression of green fluorescent protein (GFP) was observed in 95% of the infected SCG7901 and HepG2 cells with the multiple of infection (MOI) of the Ads of 100. Transfection of SCG7901 and HepG2 cells did not produce significant changes in the cell growth, and the infected cells exhibited different sensitivities to the two prodrug: SCG7901 cells infected with rAd were highly sensitive to the prodrugs, but the infected HepG2 cells were not (P<0.01). The killing effect of CDglyTK fusion gene on the target cells was much stronger than that of either the single suicide gene (P<0.01).

CONCLUSIONCDglyTK fusion gene system driven by KDR promoter selectively kills the KDR-CDglyTK SCG7901 cells and inhibits their proliferation.

Adenocarcinoma ; genetics ; metabolism ; pathology ; Adenoviridae ; genetics ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cell Survival ; drug effects ; Dose-Response Relationship, Drug ; Flucytosine ; pharmacology ; Ganciclovir ; pharmacology ; Genes, Transgenic, Suicide ; genetics ; Genetic Vectors ; Green Fluorescent Proteins ; biosynthesis ; genetics ; Humans ; Neovascularization, Pathologic ; genetics ; metabolism ; pathology ; Prodrugs ; pharmacology ; RNA, Messenger ; genetics ; metabolism ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Stomach Neoplasms ; genetics ; metabolism ; pathology ; Transfection ; Vascular Endothelial Growth Factor Receptor-2 ; biosynthesis ; genetics

OBJECTIVETo reconstruct a digital three-dimensional model of the rectum and the surrounding structures based on CT angiographic (CTA) data.

METHODSBased on air pressure enema and CTA, the chest T12 level to upper portion of the femur of a healthy volunteer was scanned with 64-slice spiral CT in the arterial phase and venous phase. The rectum and the surrounding structures were reconstructed with Mimics software based on the two-dimensional images of 856 consecutive layers obtained by Dicom 3.0 standard CT. The model was validated using finite element analysis software.

RESULTS AND CONCLUSIONThe established three-dimensional digital model allowed clear visualization of such structures of the lumbar vertebrae, pelvis, femur, abdominal aorta, internal iliac artery, external iliac artery, branches of the external iliac artery, skin, rectum, the colons, part of the small intestines, and the urinary bladder and prostate. The application of thin-layer CT and Dicom 3.0 standard renders better accuracy of the established digital model, which can provide a platform for surgical skill training and teaching of anatomy.

Adult ; Angiography ; methods ; Aorta, Abdominal ; diagnostic imaging ; Finite Element Analysis ; Humans ; Iliac Artery ; diagnostic imaging ; Image Processing, Computer-Assisted ; methods ; Imaging, Three-Dimensional ; methods ; Male ; Models, Anatomic ; Rectum ; anatomy & histology ; diagnostic imaging ; Tomography, Spiral Computed ; methods