GSDMD in peripheral myeloid cells regulates microglial immune training and neuroinflammation in Parkinson's disease

Peripheral bacterial infections without impaired blood-brain barrier integrity have been attributed to the pathogenesis of Parkinson's disease (PD). Peripheral infection promotes innate immune training in microglia and exacerbates neuroinflammation. However, how changes in the peripheral environment mediate microglial training and exacerbation of infection-related PD is unknown. In this study, we demonstrate that GSDMD activation was enhanced in the spleen but not in the CNS of mice primed with low-dose LPS. GSDMD in peripheral myeloid cells promoted microglial immune training, thus exacerbating neuroinflammation and neurodegeneration during PD in an IL-1R-dependent manner. Furthermore, pharmacological inhibition of GSDMD alleviated the symptoms of PD in experimental PD models. Collectively, these findings demonstrate that GSDMD-induced pyroptosis in myeloid cells initiates neuroinflammation by regulating microglial training during infection-related PD. Based on these findings, GSDMD may serve as a therapeutic target for patients with PD.

Feasibility investigation of three cavity clearance in treatment of perianal abscess / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To explore the feasibility of three-cavity clearance (TCC) in the treatment of perianal abscess.</p><p><b>METHODS</b>A retrospective study of patients with perianal abscess in our center from July 2013 to March 2015 were carried out. Clinical data of 25 patients undergoing TCC (TCC group) were analyzed. At the same time, based on matched gender, age and location of abscess, 25 patients undergoing incision and drainage (incision group) and 25 undergoing cutting seton (seton group) were enrolled. Postoperative pain visual analogue scale (VAS) score (the first defecation,1 week later), rate of fistula formation, fecal incontinence(Wexner score) and wound healing were compared among groups.</p><p><b>RESULTS</b>One week after operation, VAS score in seton group was 6.5±1.3, which was significantly higher than 1.3±0.5 in TCC group and 1.2±0.4 in incision group(P<0.01), while there were no significant differences of VAS among groups at the first defecation(P>0.05). Time of wound healing was (45.8±19.9), (49.2±23.1) and (53.5±24.1) days in TCC, incision and seton group respectively, without significant difference(P>0.05). Rate of fistula formation was 48.0% (12/25) in incision group, which was significantly higher than 12.0% (3/25) in TCC group and 12.0%(3/25) in seton group (all P<0.01). There was no patient with faecal incontinence in TCC group and incision group, while 2 patients with fecal incontinence were found in seton group.</p><p><b>CONCLUSION</b>Three-cavity clearance is feasible in treatment of perianal abscess, and can decrease the rate of fistula formation, ameliorate postoperative pain and protect anal function.</p>

Manufacture and application of laparoscopic extraperitoneal sigmoid colostomy / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the safety and feasibility of laparoscopic extraperitoneal sigmoid colostomy.</p><p><b>METHODS</b>Thirty-six patients with low rectal cancer undergoing laproscopic abdominoperineal resection from July 2011 to July 2012 were prospectively enrolled in the study and randomly divided into extraperitoneal colostomy group(EPC, n=18) and internal peritoneal colostomy group(IPC, n=18). Follow-up period was 4-16 (median, 7) months and postoperative complications were compared between two groups.</p><p><b>RESULTS</b>One case in EPC group was converted to IPC because of poor blood supply of the proximal sigmoid, who was eliminated from the subsequent analysis. Compared with the IPC group, the surgery time was longer in EPC group [(25.3±8.5) min vs. (14.7±6.4) min], while the difference was not statistically significant(P>0.05). Each group had 1 case of stoma ischemia, who both received the colostomy reconstructive surgery. The incidence of stoma edema was significantly higher in EPC group[35.3%(6/17) vs. 0, P<0.05). The early postoperative complications rate did not significantly different between the two groups[58.8%(10/17) vs. 27.8%(5/18), P>0.05]. The late postoperative complications rate was 22.2%(4/18) in IPC group, including 1 case of stoma prolapse, 1 case of stoma stenosis and 2 cases of parastomal hernia. No later postoperative complication occurred in EPC group.</p><p><b>CONCLUSION</b>Extraperitoneal sigmoid colostomy is an easy and safe procedure with lower late complications as compared to internal peritoneal sigmoid colostomy.</p>

Study on accuracy of endoscopic polyp size measurement by disposable graduated biopsy forceps / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To study the accuracy of endoscopic polyp size measurement by disposable graduated biopsy forceps (DGBF).</p><p><b>METHODS</b>Accurate gradation of 1 mm was made in the wire of disposable graduated biopsy forceps, which was used to measure the size of tumors under endoscopy. Fifty-eight polyps from 43 patients underwent endoscopy in our department from May to June 2013 were enrolled. Size of polyp was measured and compared among DGBF, routine estimation and direct measurement after resection. The accuracy of polyp size measurement was investigated by four colonoscopists who had finished at least 2000 procedures of colonoscopy.</p><p><b>RESULTS</b>The mean diameter of post-polypectomy measurement was (1.02±0.84) cm. Diameter was less than 1 cm in 36 polyps, 1 to 2 cm in 15, and over 2 cm in 7. The mean diameter of visual estimation was (1.29±1.07) cm, and the difference was significant as compared with actual size (P=0.000). The mean diameter measured by DGBF was (1.02±0.82) cm, and the difference was not significant as compared with actual size (P=0.775). The ratio of visual estimation to actual size was 1.29±0.31, and DGBF estimation to actual size was 1.02±0.11 with significant difference (P=0.000). The accurate rate of DGBF in estimating polyp size was 77.6% (45/58), which was obviously higher as compared to visual estimation [19.0% (11/58), P=0.000].</p><p><b>CONCLUSION</b>The accuracy of DGBF as a scale in the estimation of poly size increases as compared to visual estimation.</p>

Impact of polyamidoamine dendrimer liposome on the cellular uptake and cytotoxicity of colonic cancer cells / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the effects of polyamidoamine dendrimer (PAMAM) liposome as gene carriers on the cellular uptake and its cytotoxicity in colonic cancer cell.</p><p><b>METHODS</b>The liposome modified PAMAM was synthesized with liposome and polyamidoamine dendrimer. Plasmid PEGFP-N1 was mixed with the liposome-modified PAMAM or unmodified PAMAM to form nanoparticle complexes. The shape and size of the nanoparticle complexes were observed by transmission electron microscope and the zeta potential was measured by analytical tool. The encapsulating efficiency was determined by ultraviolet spectrophotometer in centrifuging method. After the cell lines SW620 (colonic cancer cell), MCF-7 (breast cancer cell), ECV304 (vascular endothelial cell) were transfected by the two kinds of PAMAM nanoparticle complexes, the flow cytometry was used to determine the uptake of enhanced green fluorescent protein (EGFP) gene. The cytotoxicity of PAMAM liposome nanoparticles and PAMAM nanoparticles was evaluated by MTT assay.</p><p><b>RESULTS</b>The diameter of liposome modified PAMAM complex was (192 ± 16) nm, and that of PAMAM complex was (189 ± 19) nm (P > 0.05); and the zeta potential of liposome modified PAMAM complex was higher than that of PAMAM complex [(42 ± 7) mV vs. (32 ± 7) mV, P < 0.05]. There was no significant difference in envelopment rate between the two groups [(82 ± 7)% vs. (84 ± 6)%, P > 0.05]. After the colonic cancer cell line SW620 was transfected with the two kinds of PAMAM nanoparticle complexes, the cellular uptake of the cells with the liposome-modified PAMAM complex was significantly higher than that of the cell with PAMAM complex (P < 0.05). The cellular survival rate of the cell lines with liposome-modified PAMAM complex was significantly higher than that of cell lines with PAMAM complex (P < 0.05).</p><p><b>CONCLUSION</b>The liposome modified PAMAM can improve gene transfection efficiency and suppress its cytotoxicity.</p>

Polyamidoamine dendrimer-mediated survivin antisense oligonucleotide inhibits the growth of subcutaneously transplanted colorectal cancer in nude mice / 南方医科大学学报

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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).</p><p><b>CONCLUSION</b>PAMAM can effectively deliver survivin-ASODN into transplanted colorectal tumor cells to reduce the expression of survivin and inhibit the tumor growth.</p>

Specific killing effects of combination of recombinant adenovirus containing double suicide gene driven by KDR promoter and survivin antisense oligonucleotide on colorectal cancer cells and vascular endothelial cells / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To evaluate the specific killing effects of combination of recombinant adenovirus mediated double suicide gene driven by KDR promoter and survivin antisense oligonucleotide(ASODN) on colorectal cancer cells and vascular endothelial cells.</p><p><b>METHODS</b>The 293 packaging cells were transfected with the plasmids of pAdEasy-CDglyTK and the recombinant adenovirus were generated. The KDR expressive cells of SW620, ECV304 were infected with adenovirus, meanwhile survivinASODN was transferred into the same cells. The infection rate of adenovirus and transfection efficiency of survivinASODN were observed and the expression of CDglyTK was detected by RT-PCR. The expression of survivin was measured by Western blot. The killing effects and bystander effects on SW620, ECV304 were examined through MTT method.</p><p><b>RESULTS</b>The cells which were infected with the adenovirus mediated double suicide gene could be transfected with the survivin ASODN and the infection rate was not affected as well as the transfection efficiency. The high expression of CDglyTK gene was found in SW620, ECV304 cells infected with recombinant adenovirus and survivin ASODN decreased the survivin protein level. The survival rate of gene therapy group was significantly lower than that of negative group. The combination of survivin ASODN and AdKDR-CDglyTK gene therapy showed significantly lower survival rate of SW620 and ECV304 cells as compared with the AdKDR-CDglyTK or survivin ASODN used alone (P<0.05). The survival rate was slightly lower in GCV 100 microg/ml, 5-FC 2000 microg/ml than that AdKDR-CDglyTK used alone (P>0.05). The combined therapy of AdKDR-CDglyTK and survivin ASODN showed synergistic killing efficacy and more significant bystander effects.</p><p><b>CONCLUSION</b>The combined gene therapy of AdKDR-CDglyTK system and survivin ASODN has stronger specific killing effects on colorectal cancer cells and vein endothelial cells.</p>

Biological activity of survivin antisense oligonucleotide labeled with quantum dots or green fluorescein: a comparative study / 南方医科大学学报

<p><b>OBJECTIVE</b>To compare the durability of quantum dots with that of green fluorescein for labeling survivin antisense oligonucleotide (ASODN) and investigate the difference in growth and apoptosis of cells transfected with the labeled survivin ASODN.</p><p><b>METHODS</b>Survivin ASODN labeled with quantum dots or green fluorescein was transfected into MCF-7 cells via Lipolifectmain(TM2000). The proliferation of MCF-7 cells was assessed with MTT assay, survivin mRNA expression determined by RT-PCR and its protein expression measured by Western blot analysis. The apoptosis rate of the transfected cells was estimated by flow cytometry, and the fluorescence distribution in the cells observed under fluorescent inverted microscope.</p><p><b>RESULTS</b>The mRNA and protein expressions of survivin were significantly decreased in the MCF-7 cells after cell transfection with survivin ASODN labeled with quantum dots or green fluorescein, and no significant difference was noted between the two labeling methods (P>0.05). Nor did survivin ASODN transfection with different labeling methods produced significant difference in cell proliferation and apoptotic rate (P>0.05). For green fiuorescein labeling, the fluorescence disappeared 4 days after transfection, whereas the fluorescence sustained for 1 week for quantum dots labeling.</p><p><b>CONCLUSION</b>Survivin ASODNs labeled with quantum dots and green fiuorescein do not significantly differ in survivin expression or the transfected cell proliferation and apoptosis rate, but quantum dot labeling can be more stable with longer maintcnance of the labeling.</p>

Specific killing effects of combination of double suicide gene and survivin antisense oligonucleotide on breast tumor cells and vein endothelial cells / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the selectively killing effects of combination of adenovirus mediated double suicide gene driven by kinase-domain insert containing receptor (KDR) promoter and survivin antisense oligonucleotide on breast tumor cells and vein endothelial cells.</p><p><b>METHODS</b>Human embryonal kidney cells 293 were transfected with the plasmids of pAdEasy-KDR-CDglyTK and the adenovirus was generated. The KDR expressive cells of MCF-7, ECV304 were infected by adenovirus and survivin ASODN was transferred into the same cells meanwhile. The infection rates of adenovirus and transfection efficiency of survivin ASODN were observed and the expression of CDglyTK was detected by RT-PCR. The expression of survivin was measured by Western blot. The killing effects and bystander effects on cells were assessed by MTT assay.</p><p><b>RESULTS</b>The cells infected by the adenovirus mediated double suicide gene could be transfected with the survivin ASODN and the infection rate was not affected as well as the transfection rate. The high expression of CDglyTK gene was found in the two kinds of cells and survivin ASODN decreased the survivin protein level. When survivin ASODN was transferred into MCF-7, ECV304 cells, the survival rates were 56.4% +/- 3.8% and 55.9% +/- 3.6% respectively. The combination of survivin ASODN and AdKDR-CDglyTK gene therapy showed significantly lower survival rate comparing with using each treatment alone (P < 0.05) and the survival rate decreased gradually with the increasing of the concentration of GCV and 5-FC. But the survival rate for combined gene therapy group was slightly lower in GCV 100 microg/ml, 5-FC 2000 microg/ml than that of AdKDR-CDglyTK group (P > 0.05). The combination of survivin ASODN and AdKDR-CDglyTK therapy showed synergistic killing efficacy and more significant bystander effects.</p><p><b>CONCLUSION</b>The combined therapy with AdKDR-CDglyTK system and survivin ASODN shows obvious killing effects on breast tumor cells and vein endothelial cells.</p>

Advances in the research of differentiation of embryonic stem cells into hepatocytes / 生物工程学报

Orthotopic liver transplantation has proven to be effective in the treatment of a variety of life-threatening liver diseases, however, the limitations of donated organs available and long-term immunosuppression provided an impetus for developing alternative therapies. Cell replacement strategies have been one major effective approach for overcoming the obstacles of organ transplantation in recent years. The exogenous cells should be able to proliferate and differentiate into mature hepatic cells after grafting. Use of mature hepatocytes is also hampered by limited tissue source and inability to proliferate and maintain the function for a long term in vitro. Embryonic stem cells are immortal and pluripotent and may provide a novel cell source for potential cell therapy. This review summarizes the mechanisms of controlling early liver development and hepatic differentiation of visceral endoderm in embryoid bodies, and provides an overview of diverse differentiation systems in vitro and in vivo that were applied to hepatic research in recent years. Several studies have demonstrated that ES cell-derived hepatocytes can incorporate into liver tissue and function in vivo , but a few of them have shown complete restoration of liver function after transplantation into mice with liver diseases. Further studies should be made to exploit efficient methods and clinical applications of hepatocytes derived from ES cells in the future. In addition to clinical transplantation for treatment of liver diseases, ES cells can provide a valuable tool for drug discovery applications and study on of molecular basis of hepatic differentiation.

Protective effect of GABA against hypoxic injury in rat hippocampal slices / 中国应用生理学杂志

<p><b>AIM</b>To study the mechanism of protective effect of GABA against hypoxic injury in rat hippocampal slices.</p><p><b>METHODS</b>The hippocampal slices from adult rats and extracellular recording technique were used to observe the effect of GABA on the evoked population spikes in rat hippocampal slices after hypoxia in vitro.</p><p><b>RESULTS</b>GABA can significantly delay the disappearance of PV, but have no effect on PS. When the receptor antagonist of GABA (bicuculline) and the inhibitor of Cl- channel (NPPB) were given, the protect effect could be suppressed.</p><p><b>CONCLUSION</b>GABA increases hypoxic tolerance of hippocampal slices. The mechanism of the effect of GABA may be involved in the elevation of chloride influx through GABA receptor.</p>

The role of the immunohistochemistry for hMLH1 and hMSH2 with detection of microsatellite instability to identify the kindreds with hereditary nonpolyposis colorectal cancer / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the specificity and sensitivity of the immunohistochemistry for hMLH1 and hMSH2 with detection of microsatellite instability (MSI) to identify the kindreds with hereditary nonpolyposis colorectal cancer and to analyse its value in clinical practice.</p><p><b>METHOD</b>Specimens of 16 cases with HNPCC and 16 cases with sporadic colorectal cancer were detected by immunostaining with hMLH1 and hMSH2 and MSI was also detected.</p><p><b>RESULTS</b>The specificity and sensitivity of the immunohistochemistry for hMLH1 and hMSH2 were 91.7% and 87.5% respectively. The specificity and sensitivity of MSI were 100% and 75.0%. By combining two methods, the specificity and sensitivity were 91.7% and 93.8% respectively.</p><p><b>CONCLUSIONS</b>By combination of the immunohistochemistry for hMLH1 and hMSH2 and detection of MSI to identify the kindreds with HNPCC, the specificity and sensitivity are improved which is better than to use either of them alone. And it is very easy and cheap that it can be used in clinics.</p>