An efficient and reusable quaternary ammonium fabric adsorbent prepared by radiation grafting for removal of Cr(VI) from wastewater.

A novel quaternary ammonium polyethylene nonwoven fabric for removing chromium ions from water was prepared via radiation-induced grafting of glycidyl methacrylate and further modification with N,N'-dimethylethylenediamine. The structural and morphological characteristics of the adsorbent were analyzed using Fourier transform infrared spectroscopy (FTIR), thermogravimetry and differential thermogravimetry (TG/DTG), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The influences of several principal factors, including pH value, initial Cr(VI) concentration, contact time, and coexisting anions (including SO42-, CO32-, NO3-, PO43-, and Cl-), on adsorption performance were investigated via batch tests. The results showed that the optimum removal efficiency was 99.2% at pH 3 and the maximum adsorption quantity for Cr(VI) at 25 °C was 336 mg/g. The adsorption kinetic parameters were better fitted with the pseudo-second-order kinetic model, and the equilibrium data were described very well by the Freundlich isotherm model. Furthermore, the as-synthesized adsorbent exhibited excellent regeneration and recyclability while maintaining high adsorption performance after five adsorption/desorption cycles.

Tumor-associated macrophages correlate with phenomenon of epithelial-mesenchymal transition and contribute to poor prognosis in triple-negative breast cancer patients.

BACKGROUND: Tumor-associated macrophages (TAMs) are associated with poor outcomes in multiple solid cancers and play important roles in cancer progression. Epithelial-mesenchymal transition (EMT) may account for metastasis and recurrence. However, the association between TAMs and EMT is not clarified in triple-negative breast cancer (TNBC). The aim of this study was to investigate the effects of TAMs on EMT in TNBC. MATERIAL AND METHODS: We studied specimens from 278 patients with TNBC. TAMs marker cluster of differentiation 163 and EMT-related marker E-cadherin were detected by immunohistochemistry in TNBC tissues, and their clinical significance was evaluated from the patients' medical records. RESULTS: TNBC patients with polarized cluster of differentiation 163+ TAMs infiltration and low level of E-cadherin had a significantly higher risk of aggressive features, including recurrence, histologic differentiation, and lymph node metastasis. Infiltration of TAMs was also negatively correlated with E-cadherin in TNBC tissues. Multivariate analysis indicated that infiltration of TAMs and low expression of E-cadherin were independent prognostic factors of overall survival and disease-free survival in TNBC patients. CONCLUSIONS: High infiltration of TAMs was associated with low expression of E-cadherin and could be used as an unfavorable prognostic factor for patients with TNBC.

Hypoxia-inducible factor-1 alpha Correlates with Tumor-Associated Macrophages Infiltration, Influences Survival of Gastric Cancer Patients.

Background: Hypoxia was a common feature for accelerating tumor metastasis by both inducting epithelial-mesenchymal transition (EMT) of tumor cells and polarization of tumor-associated macrophages (TAMs). The association and roles between hypoxia, EMT and TAMs in the biological behavior of gastric cancer (GC) for the time being recurrence is unclear. Material and methods: hypoixa by expression of hypoxia-inducible factor-1 alpha (HIF-1α), polarized functional status of infiltrated TAMs by immunohistochemical staining of CD68 and CD163, and the expression of E-cadherin as EMT property had been evaluated in 236 patients consecutive with histologically confirmed GC. Clinical significance was assessed for all these patients. Results: High expression of HIF-1α was found in patients with aggressive features, especially for recurrent patients. High infiltration of TAMs and abnormal expression of EMT-marker were also related to aggressive characteristics and predicted poor prognosis in GC. Meanwwhile, there existed a significant correlation among expression of HIF-1α, infiltration of TAMs and EMT marker in GC tissues. Multivariate Cox analysis revealed that high expression of HIF-1α combined TAMs infiltration were independent prognostic factors for disease-specific survival rate. Conclusion: HIF-1α is an unfavorable indicator for prognosis, may promote tumor progression through the induction of EMT and establishment of a pro-tumor immunosuppressive microenvironment. Further investigation into the therapeutic effects of blocking hypoxia is possible a potential strategy for GC treatment.

High Infiltration of Polarized CD163+ Tumor-Associated Macrophages Correlates with Aberrant Expressions of CSCs Markers, and Predicts Prognosis in Patients with Recurrent Gastric Cancer.

Background: As the most predominant tumor-infiltrating immune cells, tumor-associated macrophages (TAMs) are associated with poor outcome in multiple solid cancers and play important roles in cancer progression. Cancer stem cells (CSCs) may account for metastasis and recurrence after cancer therapy. However, the association between TAMs and CSCs is not clarified in gastric cancer (GC). The aim of the present study was to evaluate the effects of TAMs on CSCs in GC and find out the risk factors to predict recurrence and prognosis. Material and methods: This study included consecutive 236 patients with histologically confirmed primary GC. TAMs marker CD163 and CSCs-related proteins were detected by immunohistochemistry (IHC) in GC tissues and their prognostic values were all investigated. Results: High expression of CD163+ TAMs was found in patents with aggressive characteristics, especially for patents with recurrence. There existed a significant correlation between high expression of CD163 and CSCs-related markers in GC tissues. In patients with recurrence, high-expression of CD163 TAMs was an independent worse prognostic factor. Conclusion: High infiltration of TAMs was related to aggressive behavior, associated with aberrant expression of CSC markers, and an independent worse prognostic factor in GC. Targeting TAMs may be a potential treatment strategy for GC, including patients with recurrence.

[Excision of necrotic and infected tissues combined with induced membrane and external fixator technique for the treatment of chronic osteomyelitis in tibia after fracture operation].

OBJECTIVE: To investigate the clinical efficacy of excision of necrotic and infected tissues combined with induced membrane and external fixator technique to treat chronic osteomyelitis in tibia after fracture operation. METHODS: From June 2011 to June 2014, a total of 13 patients with tibia osteomyelitis were treated with excision of necrotic and infected tissues and external fixator technique in the first stage. There were 8 males and 5 females, ranging in age from 16 to 67 years old with an average of (37.3±14.3) years old. Within 6 to 8 weeks the induced membrane was formed and the induced membrane technique was applied to promote new bone forming in the second stage. RESULTS: Thirteen patients had no reinfection and achieved complete bone healing after 24 to 52 months follow-up. All the patients had satisfactory function. CONCLUSIONS: Excision of necrotic and infected tissues combined with induced membrane and external fixator technique to treat chronic osteomyelitis in tibia after fracture operation can provide satisfactory results.

Supercritical CO2 Foaming of Radiation Cross-Linked Isotactic Polypropylene in the Presence of TAIC.

Since the maximum foaming temperature window is only about 4 °C for supercritical CO2 (scCO2) foaming of pristine polypropylene, it is important to raise the melt strength of polypropylene in order to more easily achieve scCO2 foaming. In this work, radiation cross-linked isotactic polypropylene, assisted by the addition of a polyfunctional monomer (triallylisocyanurate, TAIC), was employed in the scCO2 foaming process in order to understand the benefits of radiation cross-linking. Due to significantly enhanced melt strength and the decreased degree of crystallinity caused by cross-linking, the scCO2 foaming behavior of polypropylene was dramatically changed. The cell size distribution, cell diameter, cell density, volume expansion ratio, and foaming rate of radiation-cross-linked polypropylene under different foaming conditions were analyzed and compared. It was found that radiation cross-linking favors the foamability and formation of well-defined cell structures. The optimal absorbed dose with the addition of 2 wt % TAIC was 30 kGy. Additionally, the foaming temperature window was expanded to about 8 °C, making the handling of scCO2 foaming of isotactic polypropylene much easier.

Meta-analysis of bariatric surgery versus non-surgical treatment for type 2 diabetes mellitus.

BACKGROUND: To compare short-term and long-term results of bariatric surgery vs non-surgical treatment for type 2 diabetes mellitus (T2DM). METHODS: A systematic search was conducted in the PubMed, Embase, and Cochrane Library databases for randomized controlled trials (RCTs). All statistical analysis was performed using Review Manager version 5.3. The dichotomous data was calculated using risk ratio (RR) and continuous data was using mean differences (MD) along with 95% confidence intervals (CI). RESULTS: A total of 8 RCTs with 619 T2DM patients were analyzed. Compared with non-surgical treatment group, bariatric surgery group was associated with higher rate T2DM remission (RR = 5.76, 95%CI:3.15-10.55, P < 0.00001), more reduction HbA1C (MD = 1.29, 95%CI: -1.70 to -0.87, P < 0.00001), more decrease fasting plasma glucose (MD = -36.38, 95%CI: -51.76 to -21.01, P < 0.00001), greater loss body weight (MD = -16.93, 95%CI: 19.78 to -14.08, P < 0.00001), more reduction body mass index (MD = -5.80, 95%CI: -6.95 to -4.64, P < 0.00001), more decrease triglyceride concentrations (MD = -51.27, 95%CI: -74.13 to -28.41, P < 0.0001), and higher increase density lipoprotein cholesterol (MD = 9.10, 95%CI: 7.99 to 10.21; P < 0.00001). But total and low density lipoprotein cholesterol were no significant changes. CONCLUSION: Bariatric surgery for T2DM is efficacious and improves short- and long-term outcomes as compared with non-surgical treatment.

Mesenchymal stem cells promote pancreatic adenocarcinoma cells invasion by transforming growth factor-ß1 induced epithelial-mesenchymal transition.

Mesenchymal stem cells (MSCs) could be ideal delivery vehicles for antitumor biological agents in pancreatic adenocarcinoma (PA). While the role of MSCs in tumor growth is elusive. Inflammation is an important feature of PA. In this study, we reported that MSCs pre-stimulated with the combination of TNF-α and IFN-γ promote PA cells invasion. The invasion of PA cell lines were evaluate by wound healing assay and transwell assay in vitro and liver metastasis in nude mice. We observed MSCs pre-stimulated with the combination of TNF-α and IFN-γ promoted PA cells invasion in vitro and in vivo. Consistent with MSCs promoting PA cells invasion, PA cells were found undergo epithelial-mesenchymal transition (EMT). We demonstrated that MSCs pre-stimulated with both of TNF-α and IFN-γ provoked expression transforming growth factor-ß1 (TGF-ß1). MSCs promoting EMT-mediated PA cells invasion could be reversed by short interfering RNA of TGF-ß1. Our results suggest that MSCs could promote PA cells invasion in inflammation microenvironment and should be cautious as delivery vehicles in molecular target therapy.

Inhibition of human 67-kDa laminin receptor sensitizes multidrug resistance colon cancer cell line SW480 for apoptosis induction.

The adhesion mediated drug resistance in cancer cells resulted from adhesion of the extracellular matrix is a major cause for multidrug resistance (MDR) and leads chemotherapeutic failure for colon cancer. In this study, we explored the role of 67-kDa laminin receptor (67LR) in chemotherapeutic drug resistance in colon cancer cells. SiRNA-mediated knockdown of 67LR decreased the cell adhesion when laminins were applied. Moreover, 67LR knockdown increased the expression of pro-apoptotic gene Bax but inhibited the expression of anti-apoptotic gene Bcl-2. Enhanced apoptosis was observed in 67LR siRNA-transfected SW480 cell when the cell was treated with doxorubicin for apoptosis induction. Furthermore, MTT assay revealed that the IC50 of chemotherapeutic toward SW480 cell adhesion to laminins was reduced after 67LR knockdown, indicating there was a significant increase of drug sensitivity in SW480 cell. In conclusion, our study demonstrated that 67LR plays a considerable role in the development of colon cancer MDR.

[Optical Constants Determination of Zinc Selenide by Inversing Transmittance Spectrogram Transmittance Spectra Measurement and Thermal Radiative Physical Parameters Inversion of Diesel Fuel].

A novel inversion method of optical constants of diesel fuel that is one of semitransparent liquid was developed based on spectral transmittance radio inversion calculation of optical cell with glass-liquid fuel-glass configuration, which was validated by measured the optical constants of water. The measurements of transmittance spectrogram of optical cell filled with diesel fuel in the infrared wavelength 2 - 15 µm at normal incidence were investigated by Bruke V70 FTIR spectrometer. The optical constants and thermal radiative physcial parameters of diesel fuel were achieved. The results show that, (1) The optical constants of water determined by the new method (IDTM) have good agreement with previously data sets. (2) The optical constants calculation precision of the IDTM is similar with MCDTM, which is higher than SODTM and SDTM. (3) The transmittance capability of diesel fuel in the infrared wavelength 2 - 15 µm are weak, and there exist five absorption peaks, which are respectively 2.4, 3.4, 6.2, 7.3 and 13.8 µm. (4) The spectral selectivity of optical constants and thermal radiative physcial parameters of diesel fuel are stronger, whose values are urgently varied with different wavelenths.

Treatment of gallbladder stone with common bile duct stones in the laparoscopic era.

BACKGROUND: Laparoscopic common bile duct exploration (LCBDE) for stone can be carried out by either laparoscopic transcystic stone extraction (LTSE) or laparoscopic choledochotomy (LC). It remains unknown as to which approach is optimal for management of gallbladder stone with common bile duct stones (CBDS) in Chinese patients. METHODS: From May 2000 to February 2009, we prospective treated 346 consecutive patients with gallbladder stones and CBDS with laparoscopic cholecystectomy and LCBDE. Intraoperative findings, postoperative complications, postoperative hospital stay and costs were analyzed. RESULTS: Because of LCBDE failure,16 cases (4.6%) required open surgery. Of 330 successful LCBDE-treated patients, 237 underwent LTSE and 93 required LC. No mortality occurred in either group. The bile duct stone clearance rate was similar in both groups. Patients in the LTSE group were significantly younger and had fewer complications with smaller, fewer stones, shorter operative time and postoperative hospital stays, and lower costs, compared to those in the LC group. Compared with patients with T-tube insertion, patients in the LC group with primary closure had shorter operative time, shorter postoperative hospital stay, and lower costs. CONCLUSIONS: In cases requiring LCBDE, LTSE should be the first choice, whereas LC may be restricted to large, multiple stones. LC with primary closure without external drainage of the CBDS is as effective and safe as the T-tube insertion approach.

Primary closure after laparoscopic common bile duct exploration versus T-tube.

BACKGROUND: Laparoscopic common bile duct exploration (LCBDE) is now one of the main methods for treating choledocholithiasis accompanied with cholelithiasis. The objective of our study was to assess the safety and effectiveness of laparoscopic primary closure for the treatment of common bile duct (CBD) stones compared with T-tube drainage. METHODS: Patients who underwent CBD stones were studied prospectively from 2002-2012 in a single center. A total of 194 patients were randomly assigned to group A (LCBDE with primary closure) with 101 cases and group B (LCBDE with T-tube drainage) with 93 cases. Intraoperative cholangiography and choledochoscopy were performed in all patients. Patient demographics, intraoperative findings, postoperative stay, complications, and hospital expenses were recorded and analyzed. RESULTS: There was no mortality in the two groups. Four patients (3.96%) of group A were converted to open surgery, and three patients (3.23%) in group B. The mean operating time was much shorter in group A than in group B (102.6 ± 15.2 min versus 128.6 ± 20.4 min, P < 0.05). The length of postoperative hospital stay was longer in group B (4.9 ± 3.2 d) than in group A (3.2 ± 2.1 d). The hospital expenses were significantly lower in group A. Three patients experienced postoperative complications, which were related to the usage of the T-tube in group B. The incidences of overall postoperative complications were insignificantly lower in group A. CONCLUSIONS: Laparoscopic primary closure of CBD is safe and effective for the management of CBD stones, and can be performed routinely as an alternative to T-tube drainage.

Folate-polyethylene glycol conjugated carboxymethyl chitosan for tumor-targeted delivery of 5-fluorouracil.

Targeted drug delivery has been evolving at an increasing rate due to its potential to reduce the minimum effective dose of a drug and its accompanying side effects. It has shown improved therapeutic efficacy at equivalent plasma concentrations; however, the development of effective targeted delivery systems has remained a major task. In this study, a drug carrier was designed and synthesized by conjugation of folate acid (FA) to carboxymethyl chitosan (CMCS) through a polyethylene glycol (PEG) spacer. The resulting conjugates were confirmed by 1H nuclear magnetic resonance and infrared spectroscopy. The cytotoxicity of CMCS and CMCS­5­fluorouracil (5­FU) was determined by a crystal violet stain assay. The potential of CMCS­PEG­FA for use in the targeted delivery of 5­FU was investigated using 3­(4,5­dimethylthiazol­2­yl)­2,5­diphenyltetrazolium bromide analysis in two cell lines, HeLa and A549, which contain different numbers of folate receptors on their surfaces. The MTT results revealed that in HeLa cells, the cytotoxicity of (CMCS­5­FU)­PEG­FU cells is greater compared with CMCS­5­FU, suggesting that folate receptor­mediated endocytosis may affect the cellular uptake efficiency of 5­FU­loaded CMCS­PEG­FA. The CMCS­PEG­FA conjugates presented in this study show promise as carriers for chemotherapeutic agents due to their solubility at physiological pH, efficiency in carrying chemotherapeutic agents, low cytotoxicity and targeting ability.

Increased of serum high-mobility group box chromosomal protein 1 correlated with intestinal mucosal barrier injury in patients with severe acute pancreatitis.

BACKGROUND: Secondary infections are the leading cause of death in patients with severe acute pancreatitis (SAP). The gut represents the main source of pancreatic contamination and related septic complications. High-mobility group box chromosomal protein 1 (HMGB1) was recently identified to play an important role in the SAP intestinal mucosal barrier dysfunction. OBJECTIVE: To investigate the correlation of high-mobility group box 1 (HMGB1) with intestinal barrier injury and infections in patients with severe acute pancreatitis (SAP). METHODS: The serum levels of HMGB1, amylase, lipase, and biochemical indicators were measured in 80 patients with SAP at the time of admission. Furthermore, relationship between their serum HMGB1 levels and intestinal barrier injury, infection and other clinical factors were analyzed. RESULTS: The mean value of serum HMGB1 levels was significantly higher in patients with SAP (6.02 ± 2.42 ng/mL) than that in healthy volunteers (1.87 ± 0.63 ng/mL). Serum HMGB1 levels were significantly positively correlated with the Ranson score. The HMGB1 levels were higher in patients with infection during the clinical course, the HMGB1 levels in non-survivors were higher than those in survivors, and positively correlated with DAO activity, L/M ratio, the concentration of endotoxin (R = 0.484, P <0.01). CONCLUSIONS: HMGBl level of patients with severe acute pancreatitis was significantly increased, and can be used as an important indicator to determine the intestinal barrier dysfunction and infection.

[Effect of ionic liquid [bmim][PF6] on the transient photolysis behavior of xanthone].

The transient photochemical behavior of xanthone (XAN) in 1-butyl-3-methyl imidazolium hexafluoride phosphate ionic liquid ([bmim][PF6]) or binary mixed solution with acetonitrile (MeCN) was investigated by nano-second laser photolysis techniques. The spectral blue shift of 3XAN* was observed in the neat [bmim][PF6] or IL/MeCN mixture solution compared to MeCN solution. And the yield was also increased. Moreover, the energy transfer rate constant of XAN and naphthalene (NAP) was affected by the concentrations of ionic liquid. The values decreased rapidly with increasing VIL. For example, the values were 1.2 x 10(10) mol x L(-1) x s(-1) in MeCN, and 1.1 x 10(8) mol x L(-1) x s(-1) in [bmim][PF6], respectively. The photo-induced electron transfer between XAN and N,N-dimethylaniline was also investigated by changing the concentrations of [bmim][PF6] in binary solution.

[Laser photolysis study on photo-oxidation reactions of aromatic amino acids with triplet 2-methylanthraquinone].

The transient photo-sensitive oxidation between 2-methylanthraquinone (MAQ) and aromatic amino acids (namely tryptophan, tyrosine and phenylalanine) in acetonitrile/water (1 : 1, V/V) solution was investigated by laser photolysis techniques with the excitation wavelength of 355 nm. The triplet state absorption of 2-methylanthraquinone was attributed to 390, 450 and 590 nm and the anion radical absorption of MAQ was due to 390 and 490 nm identified by the electron transfer reactions from 4-diazabicyclo [2. 2. 2] octane (DABCO) or diphenylamine (DPA) to 3MAQ*. With the decay of 3 MAQ*, the MAQ*- at 490 nm appeared, which indicated that the electron transfer reactions between 3 MAQ* and amino acids occurred. Moreover, the rate constants were deduced to be 3.0 x 10(9), 1.1 x 10(9) and 1.8 x 10(8) L x mol(-1) x s(-1) for TrpH, TyrOH and PHE, respectively. On the other hand, the free energy changes (deltaG) of the reactions showed that the proposed electron transfer steps are thermodynamically feasible.

Polymorphisms of mismatch repair gene hMLH1 and hMSH2 and risk of gastric cancer in a Chinese population.

The purpose of this study was to determine the genotype and allele frequencies of hMLH1 (-93G>A and I219V) and hMSH2 (-118T>C and IVS12-6T>C) polymorphisms in patients with gastric carcinoma and normal controls, and to evaluate the association between these polymorphisms and the risk of gastric cancer in a hospital-based Chinese population. Genomic DNA was extracted from peripheral blood lymphocytes. A TaqMan assay was used to determine the genotype and allele frequencies of hMLH1 and hMSH2 polymorphisms in data obtained from 554 gastric cancer cases and 592 controls. Unconditional logistic regression was used to assess the association between the four single nucleotide polymorphisms (SNPs) and gastric carcinoma risk. No evidence of an association among any of the four polymorphisms and the risk of gastric cancer was observed. However, when gastric cancer patients were further stratified by age, gender, smoking status, alcohol use and clinicopathological characteristics, and compared with the control populations, the combined variant genotype hMSH2 -118T>C (TC+CC) was not only associated with an increased risk of gastric cancer in subgroups of younger subjects [ages ≤63years; adjusted odds ratio (OR)=1.51, 95% confidence interval (CI), 1.05-2.16], but also with diffuse tumors (adjusted OR=1.41, 95% CI, 1.01-1.96). These data indicate that the polymorphisms of -93G>A, I219V and IVS12-6T>C are not associated with the risk of gastric cancer. However, hMSH2-118T>C combined with variant genotypes (TC+CC) may confer a potential risk of gastric cancer in the Chinese population.

[Laser photolysis studies on pyrene in ionic liquids and conventional solvents].

The photochemistry of pyrene in conventional solvents (acetone, acetonitrile, cyclohexane) and ionic liquids [Bmim] [PF6], [BuPy][BF4], R4 NNTf2 was investigated by time-resolved laser photolytic techniques. The transient absorption spectra of the excited pyrene and other radical species were compared. The absorption band of pyrene cation radical was observed in the acetone, acetronitrile and pyridinium ionic liquid [BuPy][BF4] systems. Only excited triplet pyrene was observed in cyclohexane and [Bmim][PF6] and R4 NNTf2. The result demonstrates that there was an interaction between pyrene and solvents, and the pyrene cation radical was formed by electron transfer from the excited state of pyrene to acetonitrile, acetone and [BuPy][BF4]. The possible mechanisms of the six systems were suggested.

Incidental gallbladder carcinoma diagnosed during or after laparoscopic cholecystectomy.

BACKGROUND: Gallbladder carcinoma (GC) is a highly lethal neoplasm. With the increase of cholecystectomies since the wide acceptance of laparoscopic cholecystectomy (LC), the incidental diagnosis of gallbladder carcinoma is more frequent. The aim of the present study was to report our experience with GC diagnosed during or after the performance of LC. METHODS: A total of 10,466 LCs were carried out from January 1999 to December 2007 in our hospital. Records of patients with incidental carcinoma were collected and analyzed retrospectively. RESULTS: Of all the patients, 20 (0.19%) were histopathologically diagnosed as having a GC. There were 4 men and 16 women; the median age in this group was 65.7 years (range: 37-81 years).The depth of cancer invasion was: pTis (4 cases), pT1a (2 cases), pT1b (2 cases), pT2 (6 cases), pT3 (4 cases), and pT4 (2 cases). The sensitivity and specificity of intraoperatively frozen section examination were 83.3 and 100%, respectively. Patients with in situ, pT1a and pT1b tumors underwent LC only, and there were no recurrences. The survival rate between patients with GC diagnosed during or after LC showed no difference; it was dependent on the depth of cancer invasion. CONCLUSIONS: The survival with incidental GC is related to stage, and it validates that a carefully performed LC is adequate treatment for carcinoma in situ, and stage 1a and b cancer. A frozen section examination was helpful but did not provide a definitive diagnosis. Meticulous techniques during LC, including retrieval of the gallbladder in a retrieval bag, may prevent port-site recurrence and intraperitoneal dissemination.

Laparoscopic exploration of common bile duct with primary closure versus T-tube drainage: a randomized clinical trial.

BACKGROUND: Traditionally, the common bile duct (CBD) is closed with T-tube drainage after choledochotomy and removal of CBD stones. However, the insertion of a T-tube is not without complication and the patients have to carry it for several weeks before removal. In the laparoscopic era, surgery is performed with minimally invasive techniques in order to reduce the trauma, hasten recovery, and reduce the hospital stay of patients. T-tube insertion seems to negate these benefits. This randomized study was designed to compare the two methods applied after LCBDE and to determine whether primary closure can be as safe as closure with T-tube drainage. METHODS: From May 2000 to January 2008, 93 consecutive patients with common bile duct stones (CBDS) and gallbladder in situ were enrolled in this randomized study to undergo laparoscopic cholecystectomy with laparoscopic common bile duct exploration (LCBDE). Intraoperative findings, postoperative complications, postoperative stay, and hospital expenses were recorded and analyzed. RESULTS: There was no mortality in both groups. A T-tube was inserted in 46 patients and the CBD was closed primarily in 47. There were no differences in the demographic characteristics or clinical presentations between the two groups. Compared with the T-tube group, the operative time and postoperative stay were significantly shorter, the hospital expenses were significantly lower, and the incidences of overall postoperative complications and biliary complications were statistically and insignificantly lower in the primary closure group. CONCLUSION: LCBDE with primary closure without external drainage after laparoscopic choledochotomy is feasible and as safe as T-tube insertion.