PABPN1 functions as a predictive biomarker in colorectal carcinoma.

PURPOSE: PABPN1 acts as a modulator of poly(A) tail length and alternative polyadenylation. This research was aimed to explore the role of PABPN1 in colorectal cancer (CRC). METHODS: Public databases were performed to analyze expression, location, roles of prognosis and tumor immunity and interaction with RNAs and proteins of PABPN1. To investigate PABPN1 expression in tissues, 78 CRC specimens were collected to conduct IHC, and 30 pairs of frozen CRC and corresponding adjacent normal tissues were used to conduct qRT-PCR and WB. In addition, in vitro experiments were then carried out to identify the role of PABPN1 in CRC. RESULTS: Compared with normal tissues, PABPN1 expression was significant higher in CRC. Its high level predicted poor outcome of CRC. Th1 and Treg had significant negative relationships not only with PABPN1 expression, but also with six molecules interacting with PABPN1, including IFT172, KIAA0895L, RECQL4, WDR6, PABPC1 and NCBP1. In addition, PABPN1 had negative relationships with quite a few immune markers, such as CSF1R, IL-10, CCL2 and so on. In cellular experiments, silencing PABPN1 inhibited proliferation and promoted apoptosis in HCT-116 CRC cells. CONCLUSION: In summary, PABPN1 might become a novel biomarker and correlate with tumor immunity in CRC.

Loss of α-1,2-mannosidase MAN1C1 promotes tumorigenesis of intrahepatic cholangiocarcinoma through enhancing CD133-FIP200 interaction.

CD133 is widely used as a marker to isolate tumor-initiating cells in many types of cancers. The structure of N-glycan on CD133 is altered during the differentiation of tumor-initiating cells. However, the relationship between CD133 N-glycosylation and stem cell characteristics remains elusive. Here, we found that the level of α-1,2-mannosylated CD133 was associated with the level of stemness genes in intrahepatic cholangiocarcinoma (iCCA) tissues. α-1,2-mannosylated CD133+ cells possessed the characteristics of tumor-initiating cells. The loss of the Golgi α-mannosidase I coding gene MAN1C1 resulted in the formation of α-1,2-mannosylated CD133 in iCCA-initiating cells. Mechanistically, α-1,2-mannosylation promoted the cytoplasmic distribution of CD133 and enhanced the interaction between CD133 and the autophagy gene FIP200, subsequently promoting the tumorigenesis of α-1,2-mannosylated CD133+ cells. Analysis of iCCA samples showed that the level of cytoplasmic CD133 was associated with poor iCCA prognosis. Collectively, α-1,2-mannosylated CD133 is a functional marker of iCCA-initiating cells.

Role of LncRNA MIR99AHG in breast cancer: Bioinformatic analysis and preliminary verification.

Objective: This research was aimed to preliminarily explore the clinical roles and potential molecular mechanisms of MIR99AHG and its significant transcripts in breast cancer (BRCA). Methods: Public databases were utilized to analyze the expression and prognostic roles of MIR99AHG and its transcripts. Relationships between MIR99AHG expression and immune cells infiltration were analyzed in Xiantao platform. In addition, co-expressed genes and interacting proteins of MIR99AHG were predicted. CancerSEA analyzed its relationship with functional states. Next, CNV status, DNA methylation, interacting transcription factors (TFs) and ceRNA network were analyzed to explore its possible mechanisms. Then, RNA ISH and FISH assays were used to detect its expression and location in BRCA tissues and cell lines, respectively. Finally, qRT-PCR was utilized to investigate MIR99AHG expression in cell lines. Results: Compared with the corresponding normal tissues, MIR99AHG expression levels were lower in all BRCA subtypes, and luminal B's was the lowest one. And MIR99AHG expression was negatively related to the tumor stage. In addition, 4 transcripts (ENST00000619222.4, ENST00000418813.6, ENST00000602901.5 and ENST00000453910.5) of MIR99AHG showed significant differences in the expression. Databases also suggested that the high MIR99AHG expression levels indicated good prognosis, especially in patients without lymph node metastasis. Xiantao found that MIR99AHG was positively related to 17 immune cells and negatively linked with 2 immune cells. CancerSEA analysis showed no relationships between MIR99AHG and functional states. From GEPIA and BCIP databases, 19 co-expressed genes were highly related to these four significant transcripts of MIR99AHG. StarBase, RNAct and HDOCK showed that several tumor-associated proteins, including U2AF65, hnRNPC, AEBP2, CHIC1 and so on, might interact with MIR99AHG. Genetically, BRCA had a higher proportion of MIR99AHG CNV loss than CNV gain, and the high level of DNA methylation indicated a good prognosis. Furthermore, 19 TFs were predicted to combine with the promoter of MIR99AHG. Then, we screened out 10 miRNAs potentially interacting with the significant transcripts of MIR99AHG, and five were significantly increased in breast tumors compared to normal tissues, including miR-194-5p, miR-320 b and so on, which could combine 14 mRNAs. Through ISH and FISH assays, we verified that MIR99AHG was down-regulated in BRCA samples and cell lines in comparison to non-tumor tissues and mammary epithelial cell line (MCF10A), and MIR99AHG was located both in cytoplasm and nucleus. qRT-PCR assay also showed the lower expression of MIR99AHG in breast cancer cells than that in MCF10A. Conclusion: These results indicate that MIR99AHG can be a favorable prognostic indicator for BRCA. ENST00000619222.4, ENST00000418813.6, ENST00000602901.5 and ENST00000453910.5 are significant transcripts and their down-regulation may play crucial roles in the progression of BRCA.

The Contribution of Hepatic Macrophage Heterogeneity during Liver Regeneration after Partial Hepatectomy in Mice.

Methods: In the present study, we investigated hepatic macrophage heterogeneity in murine liver regeneration after 2/3 PHx through immunofluorescence staining, fluorescence-activated cell sorting analysis, and quantitative reverse transcription-polymerase chain reaction. Results: Our research showed that Kupffer cells reduced rapidly in the early PHx and restored gradually depending on local proliferation and replenishment from infiltrating monocyte-derived macrophages. The ratio of ly6Chi to ly6Clo subset of macrophages in the liver changed dynamically, and hepatic macrophage function exhibits a significant difference in different stages of liver regeneration. Moreover, blocking infiltrating monocyte-derived macrophage recruitment augmented Kupffer cell proliferation but impaired the restoration of the hepatic macrophage pool, which led to delayed hepatocyte mitosis and liver regeneration. Conclusions: Our data suggest that hepatic macrophage changes dynamically in origin and function during liver regeneration following PHx and macrophage-targeted liver regeneration should consider macrophage heterogeneity.

Mechanistic insight into co-metabolic dechlorination of hexachloro-1,3-butadiene in Dehalococcoides.

Hexachloro-1,3-butadiene (HCBD) as one of emerging persistent organic pollutants (POPs) poses potential risk to human health and ecosystems. Organohalide-respiring bacteria (OHRB)-mediated reductive dehalogenation represents a promising strategy to remediate HCBD-contaminated sites. Nonetheless, information on the HCBD-dechlorinating OHRB and their dechlorination pathways remain unknown. In this study, both in vivo and in vitro experiments, as well as quantum chemical calculation, were employed to successfully identify and characterize the reductive dechlorination of HCBD by Dehalococcoides. Results showed that some Dehalococcoides extensively dechlorinated HCBD to (E)-1,2,3-tri-CBD via (E)-1,1,2,3,4-penta-CBD and (Z,E)-1,2,3,4-tetra-CBD in a co-metabolic way. Both qPCR and 16S rRNA gene amplicon sequencing analyses suggested that the HCBD-dechlorinating Dehalococcoides coupled their cell growth with dechlorination of perchloroethene (PCE), rather than HCBD. The in vivo and in vitro ATPase assays indicated ≥78.89% decrease in ATPase activity upon HCBD addition, which suggested HCBD inhibition on ATPase-mediated energy harvest and provided rationality on the Dehalococcoides-mediated co-metabolic dechlorination of HCBD. Interestingly, dehalogenation screening of organohalides with the HCBD-dechlorinating enrichment cultures showed that debromination of bromodichloromethane (BDCM) was active in the in vitro RDase assays but non-active in the in vivo experiments. Further in vitro assays of hydrogenase activity suggested that significant inhibition of BDCM on the hydrogenase activity could block electron derivation from H2 for consequent reduction of organohalides in the in vivo experiments. Therefore, our results provided unprecedented insight into metabolic, co-metabolic and RDase-active-only dehalogenation of varied organohalides by specific OHRB, which could guide future screening of OHRB for remediation of sites contaminated by HCBD and other POPs.

Diagnostic Value of Ultrasound in Children with Discoid Lateral Meniscus Using Either an Intracavitary Convex Array Probe or a Linear Array Probe.

This prospective study aimed to assess the usefulness of an intracavitary convex array probe (ICAP) in visualizing the lateral meniscus (LM) and improving the diagnostic utility of ultrasound (US) when diagnosing or screening for discoid lateral meniscus (DLM) in children. We included 105 knees (66 patients) that had symptomatic or asymptomatic DLM. We extracted and retrospectively reviewed data regarding patient demographics, medical records, magnetic resonance imaging (MRI), ultrasonographic features and arthroscopic findings. The inner edge of the LM visualized using an ICAP was significantly clearer than that visualized using a linear array probe, and the difference was significant (p < 0.01). The edges were better visualized in patients aged <8 y than in those aged >8 y, and the difference was significant (p < 0.001). The average widths of the LM body using an ICAP and MRI were 19.85 ± 3.63 and 24.46 ± 4.94 mm, respectively, and the wider the meniscal width, the greater was the deviation between the US and MRI measurements, which were positively correlated (r = 0.612, p < 0.001). With the use of MRI measurements and an ICAP, meniscal widths in poorly visualized LMs were greater than those in clearly visualized LMs, but this difference was not significant (p = 0.161). US scans using an ICAP and MRI were highly consistent in assessing the shape of the menisci (κ = 0.849, p < 0.001). US scan using an ICAP is a non-invasive, convenient and low-cost modality for diagnosing or screening for DLM in the pediatric population, especially in children aged <8 y.

Human umbilical cord mesenchymal stem cell transfusion in immune non-responders with AIDS: a multicenter randomized controlled trial.

We examined the safety and efficacy of human umbilical cord mesenchymal stem cell (hUC-MSC) infusion for immune non-responder (INR) patients with chronic HIV-1 infection, who represent an unmet medical need even in the era of efficient antiretroviral therapy (ART). Seventy-two INR patients with HIV were enrolled in this phase II randomized, double-blinded, multicenter, placebo-controlled, dose-determination trial (NCT01213186) from May 2013 to March 2016. They were assigned to receive high-dose (1.5 × 106/kg body weight) or low-dose (0.5 × 106/kg body weight) hUC-MSC, or placebo. Their clinical and immunological parameters were monitored during the 96-week follow-up study. We found that hUC-MSC treatment was safe and well-tolerated. Compared with baseline, there was a statistical increase in CD4+ T counts in the high-dose (P < 0.001) and low-dose (P < 0.001) groups after 48-week treatment, but no change was observed in the control group. Kaplan-Meier analysis revealed a higher cumulative probability of achieving an immunological response in the low-dose group compared with the control group (95.8% vs. 70.8%, P = 0.004). However, no significant changes in CD4/CD8+ T counts and CD4/CD8 ratios were observed among the three groups. In summary, hUC-MSC treatment is safe. However, the therapeutic efficacy of hUC-MSC treatment to improve the immune reconstitution in INR patients still needs to be further investigated in a large cohort study.

E2F2 inhibition induces autophagy via the PI3K/Akt/mTOR pathway in gastric cancer.

BACKGROUND: E2F2 is a member of the E2F transcription factor family and has important but not fully understood biological functions in cancers. The biological role of E2F2 in gastric cancer (GC) also remains unclear. METHODS: We examined the expression levels of E2F2 in GC using publicly available datasets such as TIMER, Oncomine, GEPIA, UALCAN, etc., and in our patient cohort, using quantitative real-time PCR, western blotting, and immunohistochemistry. We further investigated the effects of E2F2 on phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling, autophagy, and the migration and invasion of GC cells by the wound healing assay, Transwell assay and transmission electron microscopy. RESULTS: E2F2 was highly expressed in both GC tissues and cells compared with normal gastric tissues/cells. High E2F2 expression was associated with poor overall survival (OS). In addition, the expression of E2F2 in GC was strongly correlated with a variety of immune markers. E2F2 overexpression promoted the migration and invasiveness of GC cells in vitro through inhibition of PI3K/Akt/mTOR-mediated autophagy. CONCLUSION: High E2F2 expression was associated with the characteristics of invasive tumors and poor prognosis. E2F2 also had potential modulatory effects on tumor immunity. We discovered a novel function of E2F2 in the regulation of PI3K/Akt/mTOR-mediated autophagy and the downstream processes of cell migration and invasion.

c-Myc affects hedgehog pathway via KCNQ1OT1/RAC1: A new mechanism for regulating HSC proliferation and epithelial-mesenchymal transition.

BACKGROUND: This study aimed to probe into the potential mechanism of KCNQ1OT1 in liver fibrosis. METHODS: The pathological changes in liver tissues were observed by Masson and hematoxylin-eosin (HE) staining. The proliferation or cell cycle of hepatic stellate cells (HSCs) was analyzed by MTT or flow cytometry. The expressions of epithelial markers E-cadherin, interstitial markers Snail and Vimentin, and hedgehog signaling pathway-related molecules Hhip, Shh, and Gli2 were detected by Western blot. The interaction or binding of c-Myc with the KCNQ1OT1 promoter was analyzed by dual-luciferase reporter gene or Chromatin immunoprecipitation (ChIP)-qPCR, and the interaction between KCNQ1OT1 and RAC1 was assessed by RNA immunoprecipitation and RNA pull-down. Moreover, the stability of RAC1 protein was detected by cycloheximide-chase and ubiquitination. RESULTS: c-Myc and KCNQ1OT1 were up-regulated in liver fibrosis tissues and cells. After the interference with c-Myc in primary-1-Day HSCs, the down-regulated KCNQ1OT1 restrained HSC proliferation and EMT by down-regulating RAC1 expression and restraining the hedgehog pathway. CONCLUSION: Our results indicated that the interference with c-Myc down-regulated RAC1 expression and restrained the hedgehog pathway by down-regulating KCNQ1OT1, thus restraining HSC proliferation and EMT in liver fibrosis.

miR­375 affects the hedgehog signaling pathway by downregulating RAC1 to inhibit hepatic stellate cell viability and epithelial­mesenchymal transition.

MicroRNAs (miRNAs/miRs) are a class of non­coding RNAs that serve crucial roles in liver cancer and other liver injury diseases. However, the expression profile and mechanisms underlying miRNAs in liver fibrosis are not completely understood. The present study identified the novel miR­375/Rac family small GTPase 1 (RAC1) regulatory axis in liver fibrosis. Reverse transcription­quantitative PCR was performed to detect miR­375 expression levels. MTT, flow cytometry and western blotting were performed to explore the in vitro roles of miR­375. The dual­luciferase reporter gene assay was performed to determine the potential mechanism underlying miR­375 in liver fibrosis. miR­375 expression was significantly downregulated in liver fibrosis tissues and cells compared with healthy control tissues and hepatocytes, respectively. Compared with the pre­negative control group, miR­375 overexpression inhibited mouse hepatic stellate cell (HSC) viability and epithelial­mesenchymal transition, and alleviated liver fibrosis. The dual­luciferase reporter assay results demonstrated that miR­375 bound to RAC1. Moreover, the results indicated that miR­375 regulated the hedgehog signaling pathway via RAC1 to restrain HSC viability and EMT, thus exerting its anti­liver fibrosis function. The present study identified the miR­375/RAC1 axis as a novel regulatory axis associated with the development of liver fibrosis.

5-Fluorouracil enhances the chemosensitivity of gastric cancer to TRAIL via inhibition of the MAPK pathway.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has the ability to selectively trigger cancer cell apoptosis and can be used as a target for tumor therapy. However, gastric cancer cells are usually insensitive to TRAIL so reducing this drug resistance may improve the treatment of gastric cancer. In this study, we used Cell Counting Kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EdU) experiments to determine the effects of 5-fluorouracil (5-FU) and TRAIL on the proliferation of gastric cancer cells. An Annexin V/propidium iodide (PI) staining experiment was used to detect apoptosis, and Western blotting was used to analyze the expression levels of apoptosis-related proteins and mitogen-activated protein kinase (MAPK) pathway proteins. The antitumor effects of 5-FU and TRAIL were verified in vivo using a nude mouse tumorigenesis experiment, and a TUNEL assay was performed to evaluate apoptosis in tumor tissue from the nude mice. We found the combination of 5-FU and TRAIL had a greater inhibitory effect on the proliferation of gastric cancer cells than 5-FU or TRAIL alone both in vivo and in vitro. 5-FU enhanced TRAIL-induced gastric cancer cell apoptosis by inactivating the MAPK pathway. Overall, our analysis firstly provided new insights into the role of 5-FU in increasing sensitivity to TRAIL. 5-FU can be used as a sensitizer for TRAIL, and its administration is a potential strategy for the treatment of gastric cancer.

An Immune Risk Score Predicts Survival of Patients with Acute Myeloid Leukemia Receiving Chemotherapy.

PURPOSE: Prediction models for acute myeloid leukemia (AML) are useful, but have considerable inaccuracy and imprecision. No current model includes covariates related to immune cells in the AML microenvironment. Here, an immune risk score was explored to predict the survival of patients with AML. EXPERIMENTAL DESIGN: We evaluated the predictive accuracy of several in silico algorithms for immune composition in AML based on a reference of multi-parameter flow cytometry. CIBERSORTx was chosen to enumerate immune cells from public datasets and develop an immune risk score for survival in a training cohort using least absolute shrinkage and selection operator Cox regression model. RESULTS: Six flow cytometry-validated immune cell features were informative. The model had high predictive accuracy in the training and four external validation cohorts. Subjects in the training cohort with low scores had prolonged survival compared with subjects with high scores, with 5-year survival rates of 46% versus 19% (P < 0.001). Parallel survival rates in validation cohorts-1, -2, -3, and -4 were 46% versus 6% (P < 0.001), 44% versus 18% (P = 0.041), 44% versus 24% (P = 0.004), and 62% versus 32% (P < 0.001). Gene set enrichment analysis indicated significant enrichment of immune relation pathways in the low-score cohort. In multivariable analyses, high-risk score independently predicted shorter survival with HRs of 1.45 (P = 0.005), 2.12 (P = 0.004), 2.02 (P = 0.034), 1.66 (P = 0.019), and 1.59 (P = 0.001) in the training and validation cohorts, respectively. CONCLUSIONS: Our immune risk score complements current AML prediction models.

Characterization and immune function of the thioredoxin-interacting protein (TXNIP) from Litopenaeus vannamei.

The thioredoxin (Trx) system plays essential roles in maintenance and regulation of the redox state of cysteine residues in cellular proteins. The Trx-interacting protein (TXNIP) is a TRX inhibitory protein that works as a negative regulator in the TRX system. The function of TXNIP in invertebrates, in particular in immunity, remains unclear to date. In the current study, a novel TXNIP from Pacific white shrimp Litopenaeus vannamei was identified and characterized and its roles in immune responses was investigated. TXNIP could interact with Trx and inhibit its redox regulatory activity, suggesting that TXNIP was involved in regulation of the cellular redox state in shrimp. The expression of TXNIP was high in the stomach, gill, scape, eyestalk, epithelium, pyloric and muscle and low in the hepatopancreas, intestine, nerve, hemocytes and heart. Stimulations with pathogens white spot syndrome virus (WSSV) and Vibrio parahaemolyticus and immune stimulants poly (I:C) and LPS could significantly increase the expression of TXNIP in vivo. Silencing of TXNIP using RNAi strategy significantly facilitated the infection of V. parahaemolyticus but inhibited the infection of WSSV in shrimp. These indicated that TXNIP could be positively involved in antibacterial responses but negatively involved in antiviral responses in shrimp. Moreover, knockdown of TXNIP in vivo exerted opposite effects on expression of antimicrobial peptides anti-lipopolysaccharide factors and penaeidins and enhanced the phagocytic activity of hemocytes against bacteria. These suggested that TXNIP could play a complex role in regulation of humoral and cellular immune responses in shrimp.

Critical role for the long non-coding RNA AFAP1-AS1 in the proliferation and metastasis of hepatocellular carcinoma.

Increasing evidence has indicated that dysregulation of long non-coding RNAs (lncRNAs) can contribute to the progression and metastasis of human cancer, including HCC. Previous studies have shown that the lncRNA AFAP1-AS1 plays a critical role in cancer. However, the roles of AFAP1-AS1 in HCC remain to be determined. In the present study, AFAP1-AS1 was found to be increased in HCC tissues, and high AFAP1-AS1 expression was associated with tumor size, TNM stage, vascular invasion, and poor prognosis. Silencing of AFAP1-AS1 significantly reduced cell proliferation, clonal growth, cell migration, and invasion and increased apoptosis in vitro. Furthermore, AFAP1-AS1 silencing markedly reduced tumor growth in a murine allograft model in vivo. The results suggested that AFAP1-AS1 is important in HCC development and serves as a therapeutic target of HCC.

Calreticulin down-regulation inhibits the cell growth, invasion and cell cycle progression of human hepatocellular carcinoma cells.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most frequent cancers in the world. Calreticulin(CRT) is aberrantly overexpressed in many human cancer cells. The function of CRT in HCC cells remains unclear. We attempted to investigate the effects and the underlying mechanisms of CRT down-regulation on HCC cell growth, apoptosis, cell cycle progression and invasion. METHODS: To investigate the function of CRT in HCC cells, small interfering RNA (siRNA) was used to knock down the expression of CRT in SMMC7721 and HepG2 HCC cells. CRT expression was examined by Western blot and immunofluorescence. Cell proliferation was detected by CCK-8 assay. Cell cycle and apoptosis were measured by the flow cytometry. The invasion capability was assessed by transwell assay. The phosphorylation level of Akt was evaluated by Western blot. RESULTS: Compared with human hepatic cells L02, CRT was apparently up-regulated in SMMC7721, HepG2 and Huh7 HCC cells. Down-regulation of CRT expression effectively inhibited HCC cell growth and invasion. CRT knockdown induced cell cycle arrest and the apoptosis in SMMC7721 and HepG2 cells. Furthermore, down-regulation of CRT expression significantly decreased the Akt phosphorylation. CONCLUSIONS: CRT was aberrantly over-expressed in HCC cell lines. CRT over-expression contributes greatly to HCC malignant behavior, likely via PI3K/Akt pathway. CRT could serve as a potential biomarker and therapeutic target for hepatocellular carcinoma.

Chemical oxygen demand removal efficiency and limited factors study of aminosilicone polymers in a water emulsion by iron-carbon micro-electrolysis.

Micro-electrolysis was applied in the present study to investigate the effect of pH, iron-carbon mass ratio, contact time, and treatment batch on the removal efficiency of chemical oxygen demand (COD) within an aminosilicone emulsion. The results exhibited that the removal efficiency of COD decreased linearly with the batch increase, and this tendency was consistent under the various conditions. The adsorption of activated carbons contributes a large portion to the elimination of COD within the aminosilicone emulsion. The oxidation action of iron-carbon micro-electrolysis was proven and the aminosilicone emulsion's COD removal contribution was approximately 16%. Aminosilicone polymers were adsorbed on the surface of activated carbons and iron chips, which contributes to the decline of COD removal efficiency and limits the contribution of oxidation action.

Transumbilical single-incision endoscopic splenectomy: report of ten cases.

AIM: To investigate the feasibility and clinical application of transumbilical single-incision endoscopic splenectomy using conventional laparoscopic instruments. METHODS: Between 2010 and 2012, transumbilical single-incision endoscopic splenectomy was performed in 10 patients in our department, of whom 4 had refractory idiopathic thrombocytopenic purpura, 4 had enlarged splenic cyst and 2 had splenic hematoma. A 2.5-cm curved incision was made at the lower umbilicus edge, and a 10 mm laparoscope was inserted into the middle of the incision. A 5-mm harmonic scalpel was placed on the right side, and a 5-mm auxiliary instrument on the left side of the laparoscope. Splenic ligaments were incised with a harmonic scalpel, and the splenic pedicle was cut with an Endo-gastrointestinal anastomosis. The spleen was dissected and placed in a large retrieval bag, blended, and then removed. RESULTS: All transumbilical single-incision endoscopic splenectomies were performed successfully with mean operative time of 80 ± 5 min and mean blood loss of 150 ± 20 mL. Conversion to laparotomy or multi-port laparoscopic surgery was not required in all cases. All patients were discharged on postoperative days 4-6. During the postoperative hospitalization period, no painkillers were required. No intra-abdominal complications such as infection, ascites, gastric leakage, pancreatic leakage, or wound infection occurred in any case during the 6-mo follow-up. CONCLUSION: Transumbilical single-incision endoscopic splenectomy using conventional laparoscopic instruments is technically feasible and safe in selected patients.

Learning curve of transumbilical suture-suspension single-incision laparoscopic cholecystectomy.

AIM: To investigate the learning curve of transumbilical suture-suspension single-incision laparoscopic cholecystectomy (SILC). METHODS: The clinical data of 180 consecutive transumbilical suture-suspension SILCs performed by a team in our department during the period from August 2009 to March 2011 were retrospectively analyzed. Patients were divided into nine groups according to operation dates, and each group included 20 patients operated on consecutively in each time period. The surgical outcome was assessed by comparing operation time, blood loss during operation, and complications between groups in order to evaluate the improvement in technique. RESULTS: A total of 180 SILCs were successfully performed by five doctors. The average operation time was 53.58 ± 30.08 min (range: 20.00-160.00 min) and average blood loss was 12.70 ± 11.60 mL (range: 0.00-100.00 mL). None of the patients were converted to laparotomy or multi-port laparoscopic cholecystectomy. There were no major complications such as hemorrhage or biliary system injury during surgery. Eight postoperative complications occurred mainly in the first three groups (n = 6), and included ecchymosis around the umbilical incision (n = 7) which resolved without special treatment, and one case of delayed bile leakage in group 8, which was treated by ultrasound-guided puncture and drainage. There were no differences in intraoperative blood loss, postoperative complications and length of postoperative hospital stay among the groups. Bonferroni's test showed that the operation time in group 1 was significantly longer than that in the other groups (F = 7.257, P = 0.000). The majority of patients in each group were discharged within 2 d, with an average postoperative hospital stay of 1.9 ± 1.2 d. CONCLUSION: Following scientific principles and standard procedures, a team experienced in multi-port laparoscopic cholecystectomy can master the technique of SILC after 20 cases.

[Observation of the grafting of platelet-derived growth factor gene-modified artificial composite skin on rat wounds].

OBJECTIVE: To observe the effects of the grafting of a platelet-derived growth factor gene-modified artificial composite skin on rat wounds with full thickness defect. METHODS: Platelet derived growth factor-B (PDGF-B) eukaryotic expression plasmid was constructed, and the fibroblasts were transfected with it by liposome mediation. Artificial composite skins 1 and 2 were constructed respectively. The skin1 was composed of keratinocyte, porcine acellular dermal matrix and PDGF-B gene-transfected fibroblasts while the skin 2 contained keratinocyte, porcine acellular dermal matrix and fibroblasts. The two kinds of composite skin were grafted onto wounds on the rat back to form composite skin group 1 (C1) and 2 (C2), respectively, with 18 rats in each group. Eight rats with wounds without treatment served as control (C) group. The survival rate of the composite skin was observed at 2 post-operative weeks (POWs). The rat wounds were examined grossly on 2, 4 and 6 POWs for the calculation of wound contraction rate. Wound tissue samples were harvested for histological examination. RESULTS: (1) Up to 2 POWs, 14 grafts in C1 group survived completely, 3 with partial survival and 1 failure. In C2 group, 10 skin grafts survived completely, 4 with partial survival and 4 failures. (2) A scab was formed in the wound at 2 POW in C group. The surface of the grafted skin in C1 group was smooth, elastic, and showed good anti-friction properly, and it was better in quality compared with that in other two groups at 6 POW. (3) The wound contraction rate of the grafts in C group of rats was higher than that in C1 and C2 groups at 2, 4 and 6 POWs, while that in C1 was lower than that in C2 group. (4) Capillary formation was more intense in the grafted skins in C1 group at 2 POWs, and the epithelia differentiated well into 7 to 10 layers of epithelial cells with compact and orderly arrangement and evenly distributed fibrous tissue at 6 POWs. CONCLUSION: Repair of the wound with artificial composite skin containing PDGF-B gene could improve the quality of wound healing.

[Effect of expression of platelet-derived growth factor B gene on blood vessel reconstruction after tissue engineering skin grafting].

OBJECTIVE: To study the effect of PDGF on dermal blood vessel reconstruction by transplanted tissue-engineering skin containing PDGF-B gene to rats. METHODS: The recombined eukaryotic expression vector, pcDNA3.1-hPDGF-B, was constructed and transfected into fibroblasts mediated by LipofectAMINE. Keratinocytes + acellular dermal matrix (group A), keratinocytes + acellular dermal matrix + fibroblasts (group B), keratinocytes + acellular dermal matrix + fibroblasts with PDGF gene (group C) were recombined respectively, then transplanted them to rat dorsum and evaluated the reconstruction of blood vessels in the dermis after 2, 4, 6 week postoperation. RESULTS: In 2-4 weeks after skin grafting the vascularization rate in group C was higher than that of group B and group A. The vascularization rates in all groups had no significant differences in six weeks (P > 0.05). CONCLUSION: PDGF-B gene plays an important role in reconstruction of blood vessels in the dermis at early tissue-engineering skin grafting, which ensures the take of grafted tissue-engineering skin.