Efficacy and safety of percutaneous transhepatic biliary radiofrequency ablation in patients with malignant obstructive jaundice.

BACKGROUND: Percutaneous transhepatic cholangiodrainage (PTCD) and endoscopic retrograde cholangiopancreatography/endoscopic nasobiliary drainage are the most common clinical procedures for jaundice control in patients with unresectable malignant obstructive jaundice, yet the safety and effect of endobiliary radiofrequency ablation (EB-RFA) combined PTCD is rarely reported, in this article, we report our experience of EB-RFA combined PTCD in such patients. AIM: To retrospectively study the efficacy and safety of EB-RFA combined PTCD in patients with unresectable malignant obstructive jaundice. METHODS: Patients with unresectable malignant obstructive jaundice treated with EB-RFA under PTCD were selected, the bile ducts of the right posterior lobe was selected as the target bile ducts in all cases. The general conditions of all patients, preoperative tumour markers, total bilirubin (TBIL), direct bilirubin (DBIL), albumin (ALB), alkaline phosphatase (ALP), and glutamyl transferase (GGT) before and on the 7th day after the procedure, as well as perioperative complications, stent patency time and patient survival were recorded. RESULTS: All patients successfully completed the operation, TBIL and DBIL decreased significantly in all patients at the 7th postoperative day (P = 0.009 and 0.006, respectively); the values of ALB, ALP and GGT also decreased compared with the preoperative period, but the difference was not statistically significant. Perioperative biliary bleeding occurred in 2 patients, which was improved after transfusion of blood and other conservative treatments, pancreatitis appeared in 1 patient after the operation, no serious complication and death happened after operation. Except for 3 patients with loss of visits, the stent patency rate of the remaining 14 patients was 100% 71% and 29% at the 1st, 3rd, and 6th postoperative months respectively, with a median survival of 4 months. CONCLUSION: EB-RFA under PTCD in patients with unresectable malignant obstructive jaundice has a satisfactory therapeutic effect and high safety, which is worthy of further clinical practice.

Application of side-to-side anastomosis of the lesser curvature of stomach and jejunum in gastric bypass.

AIM: To evaluate the feasibility of side-to-side anastomosis of the lesser curvature of stomach and jejunum in laparoscopic Roux-en-Y gastric bypass (LRYGB). METHODS: Seventy-seven patients received side-to-side anastomosis of the lesser curvature of stomach and jejunum by utilization of linear stapler in LRYGB from April 2012 to July 2015 were retrospectively analyzed. RESULTS: All patients were successfully completed laparoscopic gastric bypass with the side-to-side anastomosis of the lesser curvature of stomach and jejunum. No patient was switched to laparotomy during operation. No early complications including gastrointestinal anastomotic bleeding, fistula, obstruction, deep vein thrombosis, incision infections, intra-abdominal hernia complications were found. One patient complicated with stricture of gastrojejunal anastomosis (1.3%) and six patients complicated with incomplete intestinal obstruction (7.8%). BMI and HbA1c determined at 3, 6, 12, 24 mo during follow up period were significantly reduced compared with preoperative baselines respectively. The percentage of patients who maintain HbA1c (%) < 6.5% without taking antidiabetic drugs reached to 61.0%, 63.6%, 75.0%, and 63.6% respectively. The outcome parameters of concomitant diseases were significantly improved too. CONCLUSION: Present surgery is a safety and feasibility procedure. It is effective to lighten the body weight of patients and improve type 2 diabetes and related complications.

[The effects of gastric bypass procedures on blood glucose, gastric inhibitory polypeptide and glucagon-like peptide-1 of normal glucose tolerance dogs].

OBJECTIVE: To observe postoperative glucose tolerance, gastric inhibitory polypeptide (GIP) , and glucogan-like peptide-1 (GLP-1) in normal glucose level dogs after undergoing gastric bypass procedures, and to explore the mechanism of gastric bypass procedures to treat type 2 diabetes. METHODS: The 6 dogs with normal glucose tolerance had undergone gastric bypass procedures, and measure preoperative and postoperative oral and intravenous glucose tolerance (at time points 1, 2, and 4 weeks) through changes in blood glucose, insulin, gastric inhibitory polypeptide (GIP), glucagon-like peptide-1 (GLP-1), and measure preoperative and postoperative week 4 pancreatic tissue morphology. RESULTS: Second weeks after operation, the fasting blood sugar was (3.58 ± 0.33) mmol/L, and significantly lower than preoperative (t = 3.571, P < 0.05). The GLP-1 level before oral glucose tolerance test (OGTT) and 30 minutes after OGTT were (0.90 ± 0.21) and (0.91 ± 0.19) pmol/L respectively, and significantly higher than preoperative (t value were -3.660 and -2.971, P < 0.05). GLP-1 levels began to decrease in the second week after surgery. After 4 weeks, the index recovered to the preoperative level. Four weeks after surgery when compared with preoperative, islet morphology, islet number (6.8 ± 0.8 and 7.1 ± 0.8 respectively) and islet cells (16.7 ± 2.5 and 16.3 ± 3.1 respectively) did not change significantly (P > 0.05). CONCLUSION: Gastric bypass procedures could be briefly affect normal glucose tolerance in dogs' blood glucose, insulin and diabetes-related gastrointestinal hormones.

[Application of side to side anastomosis between the lesser curvature of stomach and jejunum in laparoscopic Roux-en-Y gastric bypass].

OBJECTIVE: To evaluate the application of side-to-side anastomosis of the lesser curvature of stomach and jejunum in laparoscopic Roux-en-Y gastric bypass (LRYGB). METHODS: Clinical data of 29 patients with type 2 diabetes mellitus (T2DM) undergoing side to side anastomosis of the lesser curvature of stomach and jejunum in LRYGB from May 2012 to November 2012 in Department of General Surgery, Beijing Tiantan Hospital, Capital Medical University were analyzed retrospectively. RESULTS: All the procedures were successfully completed without conversion to laparotomy. The side-to-side anastomosis of the lesser curvature of stomach and jejunum avoided the laparoscopic suture. No gastrojejunostomy anastomotic bleeding, fistula, obstruction and other complications occurred after operation and no complications of gastrojejunostomy anastomosis were found during a follow up of 1 to 7 months. CONCLUSIONS: Side-to-side anastomosis of the lesser curvature of stomach and jejunum in LRYGB can manipulate the size of anastomosis accurately and avoid the laparoscopic suturing. It is simple and easy to learn.

BacA is indispensable for successful Mesorhizobium-Astragalus symbiosis.

A homologue of Sinorhizobium meliloti bacA was isolated from Mesorhizobium huakuii 7653R, which is capable of fixing atmospheric nitrogen in symbiotic association with leguminous Astragalus sinicus (Chinese milk vetch). Inactivation of the bacA gene abolished the ability of M. huakuii 7653R to establish a successful symbiosis with its host plant. Simultaneously, compared with wild-type M. huakuii 7653R, the bacA mutant was more sensitive to cell envelope-disrupting agents (acidic solution, ethanol, SDS, and crystal violet). Mass spectrometry analysis revealed that the very-long-chain fatty acid (27-OHC-28:0 and 29-OHC-30:0) contents of lipid A was reduced in the M. huakuii 7653R bacA mutant. Taken together, our data suggest that the cell envelope was altered in the M. huakuii 7653R bacA mutant, which might deteriorate bacterial adaption to acute environmental changes encountered in host cells and ultimately result in the failure of Mesorhizobium-legume symbiosis.

The symbiosis phenotype and expression patterns of five nodule-specific genes of Astragalus sinicus under ammonium and salt stress conditions.

In previous works, we isolated 14 nodule-specific or nodule-enhanced genes from Astragalus sinicus by suppressive subtractive hybridization. In this study, we have further identified the expression patterns of five nodule-specific genes of A. sinicus under salt and ammonium stress. Transcription levels of genes tested were quantified by quantitative fluorescence real-time RT-PCR. Results showed that: (1) About 80 mM NaCl and all stress treatments containing (NH(4))(2)SO(4) significantly inhibited nitrogen-fixing capacity of inoculated plants. About 40 mM NaCl showed relative lighter inhibition. (2) Compare with positive control at normal conditions, the expressions of all genes were significantly reduced by all ammonium stress. (3) Under salt stress without exogenous nitrogen, transcription levels of AsIIA255 and AsE246 were significantly increased after treatment for 3 days. But expressions of AsG2411, AsIIC2512, and AsB2510 were suppressed by 80 mM NaCl and not significantly affected by 40 mM NaCl. (4) Under salt stress with exogenous nitrogen, expressions of AsG2411, AsIIC2512, AsB2510, and AsIIA255 were significantly suppressed. While, the transcription level of AsE246 under 80 mM NaCl containing 1 mM (NH(4))(2)SO(4) was still higher than that of positive control. The correlation of the expression profiles of three cysteine cluster protein (CCP) genes (AsG2411, AsIIC2512, AsIIA255) and one lipid transfer protein (LTP) gene (AsE246) with the nitrogen-fixing capacities of nodules in each treatments may explain the molecular mechanisms of their supposed functions in symbiosis and nitrogen-fixing process. Our results also implied that AsIIA255 and AsE246 might play a role in the response of A. sinicus to salt stress to facilitate the nitrogen-fixation process.

Structural and regulatory genes required to make the gas dimethyl sulfide in bacteria.

Dimethyl sulfide (DMS) is a key compound in global sulfur and carbon cycles. DMS oxidation products cause cloud nucleation and may affect weather and climate. DMS is generated largely by bacterial catabolism of dimethylsulfoniopropionate (DMSP), a secondary metabolite made by marine algae. We demonstrate that the bacterial gene dddD is required for this process and that its transcription is induced by the DMSP substrate. Cloned dddD from the marine bacterium Marinomonas and from two bacterial strains that associate with higher plants, the N(2)-fixing symbiont Rhizobium NGR234 and the root-colonizing Burkholderia cepacia AMMD, conferred to Escherichia coli the ability to make DMS from DMSP. The inferred enzymatic mechanism for DMS liberation involves an initial step in which DMSP is modified by addition of acyl coenzyme A, rather than the immediate release of DMS by a DMSP lyase, the previously suggested mechanism.

Cloning and identification of opa22, a new gene involved in nodule formation by Mesorhizobium huakuii.

Using Tn5-sacB insertion mutagenesis, 3000 mutants were obtained from Mesorhizobium huakuii 7653R. Eight nodulation-defective mutants were screened by plant nodulation experiments. The DNA sequences of the contiguous region from the Tn5 insertion site were determined by thermal asymmetric interlaced PCR. A new gene was cloned and designated opa22, as judged from its structural and functional homology. Sequence analysis indicated that opa22 was composed of 774 nucleotides and encoded a protein of 257 amino acids. RPS-BLAST analysis of the Opa22 protein showed a sequence similarity (88.9%) to the opacity protein and related to surface antigens of the bacterial outer membrane, which can mediate various pathogen-host cell interactions and promote invasion. Our results from root hair curling experiments suggested that expression of the opa22 gene might occur at the stage of infection thread formation and nodule development. The complement stain HK24 was able to restore the nodule forming ability of the mutant.

Symbiotic abilities of Sinorhizobium fredii with modified expression of purL.

Previous reports showed that a transposon-induced PurL- mutant of Sinorhizobium fredii induced pseudonodules on Glycine max and the addition of 5-aminoimidazole-4-carboxamide-riboside or adenine to the plant could not restore the mutant to establish effective symbiosis. To gain a better understanding of the impact of the purL gene on symbiosis formation, we measured the effect of modified expression of this gene on the symbiotic abilities of S. fredii on soybean (G. max). A 1.98-kb in-frame deletion mutant in the purL gene of S. fredii was constructed. Transcriptional modification of the purL gene was conducted using several promoters such as those of lac, nifH, nifQ, and fixN. It was found that reduced expression of purL gene or suitable symbiotic expression of purL (such as with the promoter nifH or nifQ) can efficiently establish symbiosis of S. fredii on G. max without the exogenous supplementation of any adenine or purine precursor; at least a minimal level of expression of purL is essential for effective symbiosis with soybean.

[A preliminary study using RNA interference technique against replication of HBV in vitro].

OBJECTIVE: To identify the siRNA interference ability for the replication of HBV. METHODS: Based on the sequence of HBV in HepG2 2.2.15 cells in GenBank, one sequence targeting the C antigen of HBV was cloned into the RNA polymerase III based expression vector pSuper. This recombinant was electroporated into HepG2 2.2.15 cells and the expression of HBsAg and HBeAg was assayed using ELISA. RESULTS: The construction of the recombinant expression vector pSuper-C and its control vector pSuper was successfully confirmed by the results of enzyme digestion, electrophoresis and sequencing. However, there was no difference between the expression of HBsAg and HBeAg in the supernatant of HepG2 2.2.15 cell culture in the experimental and control groups. CONCLUSIONS: The constructed pSuper-C did not show an interfering effect on the replication of HBV in HepG2 2.2.15 cells. In order to display this effect, further study is needed

[A study of the effects on the symbiotic nitrogen fixation of Sinorhizobium fredii with the introduction of dctABD and nifA genes].

A recombinant plasmid pHN307 containing C4-dicarboxylic acid transport genes (dctABD) from Sinorhizobium meliloti, nifA genes from Klebsiella pneumoniae and reporter genes luxAB from pDB30 was constructed by using pTR102 as the vector. The pHN307 was then introduced into the S. fredii HN01, YC4 and GR3 by tri-parental mating, and the stability of pHN307 in the transconjugants under free-living and symbiotic condition was also investigated. The results of plant pot experiment indicated that the introduction of pHN307 in the transconjugants could significantly increase the nodule fresh weight, shoot dry weight (biomass) and total nitrogen content of the symbiotic plants with soybean variety of Heilong 33. When the transconjugants were in symbiotic with soybean variety of Chuanzao No. 1, HN01 (pHN307) could significantly increase its root nodule number and fresh weight; GR3 (pHN307) could significantly increase its root nodule number, nodule fresh weight, shoot dry weight and total nitrogen content, but YC4(pHN307) demonstrated negative effect under the same condition. The results of this study suggested that the introduction of dctABD and nifA could improve the symbiotic nitrogen fixation efficiency and nodulation ability of the rhizobia tested, respectively, and its effect was relevant to the characteristics of recipient rhizobia and soybean variety.