Objective:To screen the issues of management for radiation therapy equipment in an academic hospital with Delphi method.Methods: 6 specialists with different background were consulted with the questionnaire, and those questions were screened from questionnaire as being scored with the importance and analyzed by SPSS software.Results: 6 specialists included 2 radiation managers, 3 radiation professionals and 1 health administrative personnel. The authority coefficient was 0.88±0.06, and the activity coefficient was 100%. The Kendall concordance coefficient wereW=0.019(P=0.635) andW=0.237(P=0.001) in the 1st and 2nd round respectively. The coordination of the expert’s opinions was good and the results of the questionnaire were credible. There were 18 questions got from the questionnaire based on the averages and standard deviations.Conclusion: It was effectiveness that Delphi method can screen the issues of management for radiation equipment, on which we can get the direction of performance improvement based.

Objective To evaluate the clinical significance of harmonic dissection of the cystic artery in laparoscopic cholecystectomy (LC). Methods Clinical data of 800 cases of LC from July 1999 to December 2000, in which a harmonic scalpel was used to directly coagulate and sever the cystic artery, were retrospectively analyzed. Results The surgery was completed smoothly in all the cases, without intra-or post-operative bleeding at the stump of the cystic artery. Pathological section examinations under microscope showed that high temperatures achieved by harmonic scalpel were great enough to make the arterial walls coagulated and the arterial lumens obstructed. Conclusions Harmonic dissection of the cystic artery in LC is safe and reliable.

Staphylococcus aureus is the most important Gram-positive colonizer of human skin and nasal passage, causing high morbidity and mortality. SD-repeat containing protein D (SdrD), an MSCRAMM (Microbial Surface Components Recognizing Adhesive Matrix Molecules) family surface protein, plays an important role in S. aureus adhesion and pathogenesis, while its binding target and molecular mechanism remain largely unknown. Here we solved the crystal structures of SdrD N2-N3 domain and N2-N3-B1 domain. Through structural analysis and comparisons, we characterized the ligand binding site of SdrD, and proposed a featured sequence motif of its potential ligands. In addition, the structures revealed for the first time the interactions between B1 domain and N2-N3 domain among B domain-containing MSCRAMMs. Our results may help in understanding the roles SdrD plays in S. aureus adhesion and shed light on the development of novel antibiotics.
Amino Acid Sequence ; Bacterial Proteins ; chemistry ; genetics ; metabolism ; Binding Sites ; Calcium ; chemistry ; metabolism ; Calcium-Binding Proteins ; chemistry ; genetics ; metabolism ; Hydrogen Bonding ; Ligands ; Molecular Sequence Data ; Protein Binding ; Protein Structure, Tertiary ; Receptors, Cell Surface ; chemistry ; metabolism ; Recombinant Proteins ; biosynthesis ; chemistry ; genetics ; Sequence Alignment ; Staphylococcus aureus ; metabolism

Bone sialoprotein-binding protein (Bbp), a MSCRAMMs (Microbial Surface Components Recognizing Adhesive Matrix Molecules) family protein expressed on the surface of Staphylococcus aureus (S. aureus), mediates adherence to fibrinogen α (Fg α), a component in the extracellular matrix of the host cell and is important for infection and pathogenesis. In this study, we solved the crystal structures of apo-Bbp(273-598) and Bbp(273-598)-Fg α(561-575) complex at a resolution of 2.03 Å and 1.45 Å, respectively. Apo-Bbp(273-598) contained the ligand binding region N2 and N3 domains, both of which followed a DE variant IgG fold characterized by an additional D1 strand in N2 domain and D1' and D2' strands in N3 domain. The peptide mapped to the Fg α(561-575) bond to Bbp(273-598) on the open groove between the N2 and N3 domains. Strikingly, the disordered C-terminus in the apo-form reorganized into a highly-ordered loop and a β-strand G'' covering the ligand upon ligand binding. Bbp(Ala298-Gly301) in the N2 domain of the Bbp(273-598)-Fg α(561-575) complex, which is a loop in the apo-form, formed a short α-helix to interact tightly with the peptide. In addition, Bbp(Ser547-Gln561) in the N3 domain moved toward the binding groove to make contact directly with the peptide, while Bbp(Asp338-Gly355) and Bbp(Thr365-Tyr387) in N2 domain shifted their configurations to stabilize the reorganized C-terminus mainly through strong hydrogen bonds. Altogether, our results revealed the molecular basis for Bbp-ligand interaction and advanced our understanding of S. aureus infection process.
Bacterial Proteins ; chemistry ; genetics ; metabolism ; Carrier Proteins ; chemistry ; genetics ; metabolism ; Crystallography, X-Ray ; Fibrinogen ; metabolism ; Ligands ; Models, Molecular ; Mutation ; Peptide Fragments ; chemistry ; metabolism ; Protein Binding ; Protein Structure, Tertiary ; Staphylococcus aureus

Mechanosensitive (MS) channels are extensively studied membrane protein for maintaining intracellular homeostasis through translocating solutes and ions across the membrane, but its mechanisms of channel gating and ion selectivity are largely unknown. Here, we identified the YnaI channel as the Na/K cation-selective MS channel and solved its structure at 3.8 Å by cryo-EM single-particle method. YnaI exhibits low conductance among the family of MS channels in E. coli, and shares a similar overall heptamer structure fold with previously studied MscS channels. By combining structural based mutagenesis, quantum mechanical and electrophysiological characterizations, we revealed that ion selective filter formed by seven hydrophobic methionine (YnaI) in the transmembrane pore determined ion selectivity, and both ion selectivity and gating of YnaI channel were affected by accompanying anions in solution. Further quantum simulation and functional validation support that the distinct binding energies with various anions to YnaI facilitate Na/K pass through, which was defined as binding-block mechanism. Our structural and functional studies provided a new perspective for understanding the mechanism of how MS channels select ions driven by mechanical force.
Cryoelectron Microscopy ; Escherichia coli Proteins ; chemistry ; isolation & purification ; metabolism ; ultrastructure ; Ion Channels ; chemistry ; isolation & purification ; metabolism ; ultrastructure ; Mechanotransduction, Cellular ; Models, Molecular ; Quantum Theory

In the original publication the PDB numbers were not cited.