The role of the microbiota-gut-brain axis and intestinal microbiome dysregulation in Parkinson's disease.

Parkinson's disease (PD) is a complex progressive neurodegenerative disease associated with aging. Its main pathological feature is the degeneration and loss of dopaminergic neurons related to the misfolding and aggregation of α-synuclein. The pathogenesis of PD has not yet been fully elucidated, and its occurrence and development process are closely related to the microbiota-gut-brain axis. Dysregulation of intestinal microbiota may promote the damage of the intestinal epithelial barrier, intestinal inflammation, and the upward diffusion of phosphorylated α-synuclein from the enteric nervous system (ENS) to the brain in susceptible individuals and further lead to gastrointestinal dysfunction, neuroinflammation, and neurodegeneration of the central nervous system (CNS) through the disordered microbiota-gut-brain axis. The present review aimed to summarize recent advancements in studies focusing on the role of the microbiota-gut-brain axis in the pathogenesis of PD, especially the mechanism of intestinal microbiome dysregulation, intestinal inflammation, and gastrointestinal dysfunction in PD. Maintaining or restoring homeostasis in the gut microenvironment by targeting the gut microbiome may provide future direction for the development of new biomarkers for early diagnosis of PD and therapeutic strategies to slow disease progression.

NtMYB12a acts downstream of sucrose to inhibit fatty acid accumulation by targeting lipoxygenase and SFAR genes in tobacco.

MYB12 promotes flavonol biosynthesis in plants by targeting several early biosynthesis genes (EBGs) of this pathway. The transcriptions of these EBGs are also induced by sucrose signal. However, whether MYB12 is activated by sucrose signal and what the other roles MYB12 has in regulating plant metabolism are poorly understood. In this study, two NtMYB12 genes were cloned from Nicotiana tabacum. Both NtMYB12a and NtMYB12b are involved in regulating flavonoids biosynthesis in tobacco. NtMYB12a is further shown to inhibit the accumulation of fatty acid (FA) in tobacco leaves and seeds. Post-translational activation and chromatin immunoprecipitation assays demonstrate that NtMYB12a directly promotes the transcriptions of NtLOX6, NtLOX5, NtSFAR4 and NtGDSL2, which encode lipoxygenase (LOX) or SFAR enzymes catalyzing the degradation of FA. NtLOX6 and NtLOX5 are shown to prevent the accumulation of FA in the mature seeds and significantly reduced the percentage of polyunsaturated fatty acids (PUFAs) in tobacco. Sucrose stimulates the transcription of NtMYB12a, and loss function of NtMYB12a partially suppresses the decrease of FA content in tobacco seedlings caused by sucrose treatment. The regulation of sucrose on the expression of NtLOX6 and NtGDSL2 genes is mediated by NtMYB12a, whereas those of NtLOX5 and NtSFAR4 genes are independent of sucrose.

Detection of FAM172A expressed in circulating tumor cells is a feasible method to predict high-risk subgroups of colorectal cancer.

Previous studies used to enumerate circulating tumor cells to predict prognosis and therapeutic effect of colorectal cancer. However, increasing studies have shown that only circulating tumor cells enumeration was not enough to reflect the heterogeneous condition of tumor. In this study, we classified different metastatic-potential circulating tumor cells from colorectal cancer patients and measured FAM172A expression in circulating tumor cells to improve accuracy of clinical diagnosis and treatment of colorectal cancer. Blood samples were collected from 45 primary colorectal cancer patients. Circulating tumor cells were enriched by blood filtration using isolation by size of epithelial tumor cells, and in situ hybridization with RNA method was used to identify and discriminate subgroups of circulating tumor cells. Afterwards, FAM172A expression in individual circulating tumor cells was measured. Three circulating tumor cell subgroups (epithelial/biophenotypic/mesenchymal circulating tumor cells) were identified using epithelial-mesenchymal transition markers. In our research, mesenchymal circulating tumor cells significantly increased along with tumor progression, development of distant metastasis, and vascular invasion. Furthermore, FAM172A expression rate in mesenchymal circulating tumor cells was significantly higher than that in epithelial circulating tumor cells, which suggested that FAM172A may correlate with malignant degree of tumor. This hypothesis was further verified by FAM172A expression in mesenchymal circulating tumor cells, which was strictly related to tumor aggressiveness factors. Mesenchymal circulating tumor cells and FAM172A detection may predict highrisk stage II colorectal cancer. Our research proved that circulating tumor cells were feasible surrogate samples to detect gene expression and could serve as a predictive biomarker for tumor evaluation.

Gap junction composed of connexin43 modulates 5­fluorouracil, oxaliplatin and irinotecan resistance on colorectal cancers.

Chemotherapy is one of the most commonly used therapeutic strategies for metastatic colon cancer. However, the development of resistance to chemotherapeutic agents limits their application in clinical use. The underlying mechanisms of this resistance development require further elucidation. The current study investigated the effects of connexin43 (Cx43) gap junctions on 5­fluorouracil (5­FU), oxaliplatin and irinotecan in colon cancer cells. Three different methods were used to manipulate Cx43 gap junction function: i) Cell culture at different densities; ii) pretreatment with a Cx43 specific inhibitor or enhancer; and iii) Cx43 gene knock­down. Results indicated that the cell toxicity of 5­FU, oxaliplatin and irinotecan was cell density­dependent, which was mediated by gap junctions. Downregulation of Cx43 gap junction functioning attenuated 5­FU, oxaliplatin and irinotecan toxicity in colon cancer cells, which was increased in cells treated with a Cx43 gap junction function enhancer. Thus, the results of the present study suggest that resistance to 5­FU, oxaliplatin and irinotecan in colon cancer cells was relative to Cx43 expression loss as cancer developed, which may indicate a novel basis for therapeutic strategy development to combat drug resistance in numerous cell types, in addition to colon cancer cells.

[Application of digital 3D technique combined with nanocarbon-aided navigation in endoscopic sentinel lymph node biopsy for breast cancer].

OBJECTIVE: To study the clinical value of digital 3D technique combined with nanocarbon-aided navigation in endoscopic sentinel lymph node biopsy for breast cancer. METHODS: Thirty-nine female patients with stage I/II breast cancer admitted in our hospital between September 2014 and September 2015 were recruited. CT lymphography data of the patients were segmented to reconstruct digital 3D models, which were imported into FreeForm Modeling Surgical System Platform for visual simulation surgery before operation. Endoscopic sentinel lymph node biopsy and endoscopic axillary lymph node dissection were then carried out, and the accuracy and clinical value of digital 3D technique in endoscopic sentinel lymph node biopsy were analyzed. RESULTS: s The 3D models faithfully represented the surgical anatomy of the patients and clearly displayed the 3D relationship among the sentinel lymph nodes, axillary lymph nodes, axillary vein, pectoralis major, pectoralis minor muscle and latissimus dorsi. In the biopsy, the detection rate of sentinel lymph nodes was 100% in the patients with a coincidence rate of 87.18% (34/39), a sensitivity of 91.67% (11/12), and a false negative rate of 8.33% (1/12). Complications such as limb pain, swelling, wound infection, and subcutaneouseroma were not found in these patients 6 months after the operation. CONCLUSION: Endoscopic sentinel lymph node biopsy assisted by digital 3D technique and nanocarbon-aided navigation allows a high detection rate of sentinel lymph nodes with a high sensitivity and a low false negative rate and can serve as a new method for sentinel lymph node biopsy for breast cancer.

[Expression of Rictor and mTOR in colorectal cancer and their clinical significance].

OBJECTIVE: To explore the expression of Rictor and mTOR in the colorectal cancer and their clinical significance. METHODS: The expression levels of Rictor and mTOR in HCT116, SW480, LoVo and HCoEpiC cells were detected by indirect immunofluorescence and Western blotting. Sixty-two paraffin-embedded surgical specimens of colorectal cancer tissue and adjacent tissues were examined for Rictor expression using immunohistochemistry. The association of the expression levels of Rictor protein with the clinicopathologic features and the overall survival of the patients was analyzed. RESULTS: The expression level of Rictor was significantly higher in colorectal cancer tissues than in the adjacent tissues (P<0.05). The expression levels of Rictor and mTOR in the colon cancer cell lines were higher than those in human normal colon epithelial cell line HCoEpiC. The expression of Rictor was correlated with Dukes stage and lymphatic metastasis of the tumors but not with other clinicopathological parameter (P>0.05). Patients with Rictor expression had a lower overall survival rate than those without Rictor expression. CONCLUSION: Rictor overexpression is associated with the carcinogenesis and progression of colorectal cancer and can be an independent indicator for evaluating the prognosis of colorectal cancer patients.

Acanthoic acid inhibits LPS-induced inflammatory response by activating LXRα in human umbilical vein endothelial cells.

Acanthoic acid, a pimaradiene diterpene isolated from Acanthopanax koreanum, has been reported to have anti-inflammatory activities. However, the effect of acanthoic acid on vascular inflammation has not been investigated. The aim of this study was to investigate the anti-inflammatory effects of acanthoic acid on lipopolysaccharide (LPS)-induced inflammatory response in human umbilical vein endothelial cells (HUVECs). The production of cytokines TNF-α and IL-8 was detected by ELISA. The expression of VCAM-1, ICAM-1, E-selectin, NF-κB and LXRα were detected by Western blotting. Adhesion of monocytes to HUVECs was detected by monocytic cell adhesion assay. The results showed that acanthoic acid dose-dependently inhibited LPS-induced TNF-α and IL-8 production. Acanthoic acid also inhibited TNF-α-induced IL-8 and IL-6 production. LPS-induced endothelial cell adhesion molecules, VCAM-1 and ICAM-1 were also inhibited by acanthoic acid. Acanthoic acid inhibited LPS-induced NF-κB activation. Furthermore, acanthoic acid dose-dependently up-regulated the expression of LXRα. In addition, our results showed that the anti-inflammatory effect of acanthoic acid was attenuated by transfection with LXRα siRNA. In conclusion, the anti-inflammatory effect of acanthoic acid is due to its ability to activate LXRα. Acanthoic acid may be a therapeutic agent for inflammatory cardiovascular disease.

Farrerol inhibits IL-6 and IL-8 production in LPS-stimulated human gingival fibroblasts by suppressing PI3K/AKT/NF-κB signaling pathway.

OBJECTIVES: Farrerol, a new type of 2,3-dihydro-flavonoid isolated from rhododendron, has been shown to have anti-bacterial and anti-inflammatory activities. In the present study, we investigated the anti-inflammatory effects of farrerol on the production of IL-6 and IL-8 in human gingival fibroblasts (HGFs) treated with lipopolysaccharide (LPS). METHODS: The cytotoxicity of farrerol was determined using the MTT assay. The production of IL-6 and IL-8 was measured using ELISA and qRT-PCR. The effects of farrerol on PI3K, Akt phosphorylation, and NF-κB activation were detected using western blotting analyses. RESULTS: These results showed that farrerol inhibited LPS-induced IL-6 and IL-8 production in a dose dependent manner. LPS-induced NF-κB activation was suppressed by farrerol. Furthermore, farrerol suppressed LPS-induced PI3K and Akt phosphorylation, which are upstream molecules of NF-κB. CONCLUSION: These results indicated that farrerol attenuated IL-6 and IL-8 production by inhibition of PI3K and AKT phosphorylation, resulting in an inhibition of NF-κB activation. Farrerol may be a therapeutic agent for the treatment of periodontal disease.

Neoadjuvant chemotherapy (NCT) plus targeted agents versus NCT alone in colorectal liver metastases patients: A systematic review and meta-analysis.

PURPOSE: To assess the efficacy of neoadjuvant chemotherapy (NCT) plus targeted agents versus NCT alone for the treatment of colorectal liver metastases (CRLM) patients. METHODS: Trials published between 1994 and 2015 were identified by an electronic search of public databases (MEDLINE, EMBASE, Cochrane library). All clinical studies were independently identified by two authors for inclusion. Demographic data, treatment regimens, objective response rate (ORR), hepatic resection and R0 hepatic resection rate were extracted and analyzed using Comprehensive MetaAnalysis software (Version 2.0). RESULTS: A total of 40 cohorts with 2099 CRLM patients were included: 962 patients were treated with NCT alone, 602 with NCT plus anti-epidermal growth-factor receptor (EGFR)-monoclonal antibodies (MoAbs) and 535 with NCT plus bevacizumab. Pooled ORR was significantly higher for NCT plus bevacizumab or anti-EGFR-MoAbs than NCT alone [relative risk (RR) 1.53, 95% CI 1.30-1.80; p < 0.001; RR 1.53, 95% CI: 1.27-1.83, p < 0.001; respectively]. NCT plus bevacizumab significantly improved R0 hepatic resection rate (RR 1.61, 95% CI: 1.27-2.04, p < 0.001), but not for overall hepatic resection rate (RR 1.26, 95% CI: 0.81-1.94, p = 0.30). While hepatic resection and R0 hepatic resection rate was comparable between NCT plus anti-EGFR-MoAbs and NCT alone (p = 0.42 and p = 0.37, respectively). CONCLUSIONS: In comparison with NCT alone, NCT plus bevacizumab significantly improve ORR and R0 hepatic resection rate but not for hepatic resection rate. Our findings support the need to compare NCT plus bevacizumab with NCT alone in the neoadjuvant setting in large prospective trials due to its higher hepatic resection rate and R0 hepatic resection rate in CRLM patients.

Patchouli alcohol protects against lipopolysaccharide-induced acute lung injury in mice.

BACKGROUND: Patchouli alcohol (PA), a natural compound isolated from Pogostemon cablin, has been reported to possess anti-inflammatory activity. However, the effects of PA on lipopolysaccharide (LPS)-induced acute lung injury (ALI) have not yet been studied. In the present study, we investigated in vivo the effect of PA on ALI induced by LPS. METHODS: Mice were administrated intranasally with LPS to induce lung injury. PA was administrated intraperitoneally 1 h before or after the LPS challenge. RESULTS: The results showed that PA significantly decreased the wet-to-dry weight ratio of lungs and the number of total cells, neutrophils, and macrophages in bronchoalveolar lavage fluid at 7 h after the LPS challenge. In addition, PA also suppressed the production of inflammatory cytokines, such as tumor necrosis factor-α, interleukin-1ß, and interleukin-6 in bronchoalveolar lavage fluid. Furthermore, Western blot analysis showed that PA inhibited the phosphorylation of IκB-α and p65 nuclear factor κB (NF-κB) induced by LPS. CONCLUSIONS: Our results suggest that the anti-inflammatory effects of PA against LPS-induced ALI may be due to its ability to inhibit NF-κB signaling pathways.

Curcumin induces apoptosis in SGC-7901 gastric adenocarcinoma cells via regulation of mitochondrial signaling pathways.

Curcumin, a polyphenol compound derived from the rhizome of the plant Curcuma longa L. has been verified as an anticancer compound against several types of cancer. However, understanding of the molecular mechanisms by which it induces apoptosis is limited. In this study, the anticancer efficacy of curcumin was investigated in human gastric adenocarcinoma SGC-7901 cells. The results demonstrated that curcumin induced morphological changes and decreased cell viability. Apoptosis triggered by curcumin was visualized using Annexin V-FITC/7- AAD staining. Curcumin-induced apoptosis of SGC-7901 cells was associated with the dissipation of mitochondrial membrane potential (MMP) and the release of cytochrome c into the cytosol. Furthermore, the down-regulation of Bcl-2 and up-regulation of Bax that led to the cleavage of caspase-3 and increased cleaved PARP was observed in SGC-7901 cells treated with curcumin. Therefore, curcumin-induced apoptosis of SGC-7901 cells might be mediated through the mitochondria pathway, which gives the rationale for in vivo studies on the utilization of curcumin as a potential cancer therapeutic compound.

[Clinical application of 64-slice computed tomographic angiography-based virtual colonoscopy in the diagnosis of colonic tumors].

OBJECTIVE: To investigate the clinical value of 64-slice computed tomographic angiography (CTA)-based virtual colonoscopy in the diagnosis of colonic tumors. METHODS: Philips/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. RESULTS: The 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. CONCLUSION: Virtual 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.

In vitro and in vivo assessment of an intelligent artificial anal sphincter in rabbits.

Artificial sphincters have been developed for patients with fecal incontinence, but finding a way to make such sphincters more "intelligent" remains a problem. We assessed the function of a novel intelligent artificial anal sphincter (IAAS) in vitro and in vivo in rabbits. After the prosthesis was activated, rabbits were continent of feces during 81.4% of the activation time. The fecal detection unit provided 100% correct signals on stool in vitro and 65.7% in vivo. The results indicated that the IAAS could efficiently maintain continence and detect stool; however, the IAAS is still in the preliminary experimental stage and more work is needed to improve the system.

[Inhibitory effect of recombinant adenovirus containing CDglyTK double suicide gene driven by KDR promoter on human stomach adneocarcinoma SCG7901 cells in vitro].

OBJECTIVE: To 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. METHODS: SCG7901, 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. RESULTS: With 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. CONCLUSION: The 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.

[A double suicide gene system driven by KDR promoter selectively kills human colon adneocarcinoma SW480 cells].

OBJECTIVE: To study the selective killing effect of adenovirus (Ad)-mediated double suicide gene system driven by the KDR promoter (KDR-CDglyTK) on human colon adneocarcinoma SW480 cells. METHODS: KDR-expressing SW480 cells and LS174T cells that did not express KDR were infected by KDR-CDglyTK, and the infection efficiency and the expression of CDglyTK in the cells were detected by RT-PCR. The infected cells were treated with the prodrugs 5-FC and GCV at different concentrations, and the cell-killing effects and bystander effects were evaluated by MTT method. DNA content and the cell cycle changes in SW480 cells were detected by flow cytometry. RESULTS: The expression of green fluorescent protein (GFP) was observed in 95% of the infected SW480 and LS174T cells with a multiplicity of infection (MOI) of 100. RT- PCR demonstrated that the product of CD/TK gene existed in SW480 cells infected by Ad- KDR- CD/TK, but not in infected LS174 cells. The infected SW480 cells exhibited high sensitivity to the prodrugs, but the infected LS174T cells did not (P<0.01). Bystander effects of the double suicide gene system were observed in the coculture of the infected and non-infected SW480 cells. At the MOI of 100, treatment of the infected cells with the prodrugs resulted in increased cell percentage in G(0)-G(1) phase and decreased percentage in S phase and the prodrug-treated cells showed an apoptotic peak in flow cytometry. CONCLUSION: CDglyTK fusion gene system driven by the KDR promoter selectively kills and induces the apoptosis of the KDR-CDglyTK SW480 cells.

[A double suicide gene system driven by KDR promoter selectively kills human hepatic carcinoma cells and human umbilical vein endothelial cells].

OBJECTIVE: To study the selective killing effects of adenovirus (Ad)-mediated double suicide gene system driven by KDR promoter (KDR-CdglyTK) on the human hepatic carcinoma cells and human umbilical vein endothelial cells (HUVECs). METHODS: KDR-expressing BEL-7402 and HUVECs and HepG2 cells that did not express KDR were infected by KDR-CdglyTK, and the infection efficiency and the expression of CdglyTK in the cells was detected by RT-PCR. The infected cells were treated with the the prodrugs 5-FC and GCV at different concentrations, and the cell-killing effects and bystander effects were evaluated by MTT method. RESULTS: At the multiplicity of infection (MOI) of 100, the recombinant AdKDR-CDglyTK showed similar infection efficiency in the 3 cell lines. RT-PCR demonstrated CDglyTK expression in the recombinant adenovirus and the 3 infected cell lines. BEL-7402 and HUVECs infected by the KDR-CdglyTK, but not the HepG2 cells, were highly sensitive to the prodrugs (P<0.001). Bystander effects of the double suicide gene system were observed in the coculture of the infected and non-infected BEL-7402 and HUVECs. CONCLUSION: The double suicide gene system driven by KDR promoter has specific killing effect on KDR-expressing hepatocellular carcinoma cells and HUVECs.

[Effect of 5-aminolevulinic acid-mediated photodynamic therapy on human gastric cancer xenografts in nude mice in vivo].

OBJECTIVE: To 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. METHODS: Cultured 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. RESULTS: The 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. CONCLUSIONS: 5-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.

[Polyamidoamine dendrimer-mediated survivin antisense oligonucleotide inhibits the growth of subcutaneously transplanted colorectal cancer in nude mice].

OBJECTIVE: To evaluate the inhibitory effects of survivin antisense oligonucleotide (survivin-ASODN) mediated by polyamidoamine dendrimer (PAMAM) against the growth of subcutaneously transplanted colorectal cancer in nude mice. METHODS: Nude mouse models bearing colorectal cancer was established by subcutaneous injection of SW620 cells. Survivin- OSADN (300 microg/L) was mixed with 4.06 microg/L PAMAM or liposome to prepare two transfection complexes, and their morphologies were observed by transmission electron microscope. The particle size of the prepared complexes was determined by laser particle size analyzer, and the zeta potential was measured. The encapsulation efficiency and the DNA release rate in vitro were determined by ultraviolet spectrophotometer. The transfection complexes were then directly injected into the xenografts of the tumor-bearing nude mice. The tumor volume changes were observed, and the expression of survivin in the transplanted tumor was measured by Western blotting. RESULTS: The PAMAM-survivin-ASODN complex had a significantly smaller diameter and greater zeta potential than liposome-survivin-ASODN (P<0.01 and 0.05, respectively). The encapsulation efficiency was comparable between the two complexes. In in vitro condition, PAMAM-survivin-ASODN allowed sustained survivin-ASODN release for as long as 14 days, as compared with the 5 days for the liposome complex. After injection into the tumor xenografts, PAMAM-survivin- ASODN resulted in significantly lower expression of survivin protein in the transplanted tumors (P<0.05), and also in significantly greater reduction of the tumor volume than the liposome complex (P<0.05). CONCLUSION: PAMAM can effectively deliver survivin-ASODN into transplanted colorectal tumor cells to reduce the expression of survivin and inhibit the tumor growth.

[Reconstruction of a digital three-dimensional model of the rectum and the surrounding structures based on CT angiographic data].

OBJECTIVE: To reconstruct a digital three-dimensional model of the rectum and the surrounding structures based on CT angiographic (CTA) data. METHODS: Based 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 CONCLUSION: The 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.