Non-proline cis peptide bond is rarely found in proteins. The recent surveys revealed that this unusual peptide configuration is by no means a curiosity, but overwhelmingly occurs at functionally important sites. However one still doubts whether it is related to crystal packing interactions, since all non-proline cis peptide bonds identified so far are from crystal structures. A toxin BmK M1 from the scorpion Buthus martensii Karsch have been crystallized as a dimer in space group P212121 with unit-cell dimensions a = 76.39 (A),b=52.77 (A), c=27.12 (A). This dimeric structure was solved by molecular replacement and refined to R=0.109 for all reflections at a resolution of 1.4 (A). The extensively refined structure definitely shows that the cis peptide bond Pro9-His10 equally occurs in both molecule A and molecule B in the dimer. The observation manifested that this striking non-proline cis peptide is not related to crystal packing, but caused by certain intrinsic factors. The detailed analyses and comparison with the structure of BmK M8, which is homologous to M1 but has trans peptide bond 9-10, showed that the five-residue reverse (8 ～12) with a consensus sequence (-KPXNC-) may be the intrinsic structural element for the cis form of this peptide bond. A pair of well organized main-chain hydrogen bond between residues 10 in cis unit and 64 at C-terminus forms main tertiary interactions to stabilize this energetically unfavorable peptide bond.

Objective To evaluate surgical management of pancreatic duct stones.Methods From 1997 to 2007, 24 cases of pancreatic duct stones underwent surgical treatment, the clinical data were retrospectively analyzed. Results In this study, 17 cases underwent lithotomy by longitudinal pancreatic duct incision, Roux-en-Y anastomosis(side-to-side) of pancreatic duct to jejunum, extra drainageof the main pancreatic duct was done in two cases, hepaticojejunostomy in three cases, pancreaticcystojejunostomy in one case. One case suffered from postoperative bleeding at pancreatic ojejunostomy, one from stress ulcer, and both were cured by conservative treatment. Three cases underwent pancreaticeduodenectomy, anastomosis bleeding occurred in one patient, and was cured by conservative method. One case underwent duodenum-preserving resection of the head of the pancreas, 2 cases underwent distal pancreatectomy, one case underwent lithotomy by pancreatic duct incision and primary closure, no postoperative complications occurred among those patients. 21 cases were followed up, results were excellentin 17 patients. Conclusions Lithotomy by longitudinal pancreatic duct incision, Roux-en-Y anastomosisof pancreatic duct to jejunum is the main and effective surgical procedure, while duodenum preserving pancreatic head resection and lithotomy by pancreatic duct incision and primary closure are also rational for the treatment of pancreatic duct stones.

OBJECTIVETo investigate the rationality and feasibility of primary closure of the common bile duct after choledochotomy for common bile duct calculi.

METHODSFrom January 1990 to June 2001, 386 patients with the evidence of stones in the common bile duct underwent choledochotomy. Among them, 215 received primary closure of the common bile duct (group A) and 171 T-tube drainage (group B). The patients with emergency operations were excluded. Intraoperative choledochoscopy or cholangiography was routinely performed to rule out the possibility of retained stones. The duct was meticulously stitched using 0/3 to 0/5 absorbent sutures for primary closure. A T-tube was placed in the subhepatic space in the patients of both groups.

RESULTSPostoperative bile leakage was seen in 9 patients of group A and in 5 of group B, respectively (P > 0.05), and no reoperations were necessary. After surgery, the average time and volume of transfusion was 4.9 days and 9.1 liters in group A, versus 7.3 days and 12.8 liters in group B (P < 0.01). The patients in group B had a longer postoperative hospital stay than the those in group A (average 17.6:10.0 days, P < 0.01). T-tube removal resulted in bile peritonitis in 5 patients at day 16, 17, 19, 21 and 22 after surgery in group B, and 3 patients required repeated surgery.

CONCLUSIONSPrimary closure of the common bile duct after choledochotomy is safe, effective, and inexpensive in selected patients with common bile duct calculi, and should be regarded as an alternative procedure.

Adult ; Aged ; Biliary Tract Surgical Procedures ; methods ; Choledocholithiasis ; surgery ; Common Bile Duct ; surgery ; Female ; Humans ; Male ; Middle Aged ; Retrospective Studies ; Treatment Outcome

Pancreatic duct stone is a sequel of chronic pancreatitis and may be found in the main ducts,side branches or parenchyma.These stones obstruct the pancreatic ducts and produce ductal hypertension,which leads to pain,the cardinal feature of CP.Surgical operation has been the preferred treatment of pancreatic duct stones in many domestic and external pancreatic medical centers.Lithotomy by longitudinal pancreatic duct incision and Roux-en-Y anastomosis of pancreatic duct to jejunum is the main and effective surgical procedure,while micro-surgery was also rational for the treatment of pancreatic duct stones.However,further studies with a larger sample size and longer follow-up duration are needed to improve the surgical technique and verify our initial results.

OBJECTIVE To prepare C-phycocyanin nanoparticles （CPC-NPs） and evaluate the in vitro mechanism of CPC- NPs on acute lung injury induced by lipopolysaccharide （LPS） combined with seawater. METHODS Ion crosslinking method was used to prepare CPC-NPs using CPC as the drug， carboxymethyl chitosan （CMCS） as the carrier， and CaCl2 as the crosslinking agent. The basic characterization of CPC-NPs was carried out. Mouse alveolar type Ⅱ epithelial cells MLE-12 and macrophages RAW264.7 were divided into 7 groups： normal group （Con group）， model group （Mod group）， blank NPs group， CPC-NPs 30， 60， 120 and 240 μg/mL groups. Except for the Con group， all other groups were treated with a combination of 10 μg/mL LPS and 25% seawater for 6 hours. After modeling， each treatment group was treated with corresponding drugs for 24 hours. The levels of malondialdehyde （MDA）， total antioxidant capacity （T-AOC）， superoxide dismutase （SOD）， catalase （CAT）， and glutathione peroxidase （GSH-Px） in MLE-12 cells， as well as the expression levels of B-cell lymphoma-2 （Bcl-2）， Bcl-2 associated X protein （Bax）， caspase-3 protein and mRNA， CAT and glutathione S-transferase （GST） mRNA were determined. The levels of interleukin- 1β （IL-1β）， tumor necrosis factor-α （TNF-α） and IL-6 in RAW264.7 cells， as well as the expression levels of NOD-like receptor thermal protein domain associated protein 3 （NLRP3）， cleaved caspase-1 protein， and mRNA expressions of IL-1β，TNF-α， IL-6 and inducible nitric oxide synthase （iNOS） were all detected. RESULTS The prepared CPC-NPs had particle size of （675.69±64.58） nm， Zeta potential of （－20.11± E-mail：zhangleifang1986@163.com 0.98） mV， polydispersity coefficient of 0.455±0.010 （n＝3）；entrapment efficiency of 35.60%， and drug loading of 16.13%；CPC-NPs had regular spherical shapes， where the drug could be sustainably released for more than 30 hours. Compared with Mod group， the levels of T-AOC， SOD， CAT （excluding the 30 μg/mL group of CPC-NPs） and GSH-Px， mRNA expressions of CAT and GST， as well as the Bcl-2/Bax protein ratio and mRNA ratio were significantly increased in MLE-12 cells of different concentration groups of CPC-NPs， while MDA levels and caspase-3 protein and mRNA expression were significantly reduced （P＜0.01 or P＜0.05）. Compared with Mod group， the levels of IL-1β， TNF-α and IL-6， NLRP3 and cleaved-caspase-1 protein expressions， as well as the mRNA expressions of IL-1β， TNF-α， IL-6 and iNOS in RAW264.7 cells of different concentration groups of CPC-NPs were significantly reduced （P＜0.01 or P＜0.05）. CONCLUSIONS CPC-NPs with lung targeting and sustained release property were prepared successfully， which can alleviate acute lung injury induced by LPS combined with seawater through antioxidant stress， inhibiting cell apoptosis and inflammatory response.

Objective: To investigate and compare the attitudes of clinical nurses and nursing managers towards float nurse, and to provide references for the implementation of nurse mobile practice mode in China. Methods: By stratified sampling, the survey was conducted on clinical nurses and nursing managers of 15 tertiary hospitals in 9 prefecture-level cities in Fujian. Results: A total of 9 389 valid questionnaires were recovered, including 525 for nursing managers and 8 864 for clinical nurses. By comparing the attitudes between two groups, it was found that nursing managers who knew more about mobile practice were more willing to practice floating practice, including 50.86% (267/525) heard and inquired, 49.14% (258/525) willing to float, than clinical nurses who paid less attention, including 32.41% (2 873/8 864) heard and inquired, 38.87% (3 445/8 864) willing to float. Multi-factor analysis showed that among nursing managers, those with a bachelor’s degree or above was more willing to float. While among clinical nurses, young, unmarried, side, bachelor degree or above were more willing to float. On the choice of flow mode, nursing managers were inclined to float between hospitals (46.54%, 215/525), but clinical nurses were prone to community float (42.45%, 3 142/8 864). Furthermore, nursing managers had higher requirements on the professional title and seniority of float nurse, and 39.43% (207/525) believe that the professional title should be supervisor, while 81.71% (429/525) thought that length of service as a nurse should be 5 years or more. Conclusion There are differences between clinical nurses and nursing managers in such aspects as the intention of floating practice, obstacles and guarantee factors, cognition and selection of demanders, and acceptance of practice threshold. The above differences should be fully considered in the trial of the "Internet + Nursing" floating practice mode for nurses.