3T3 Cells ; Animals ; Cell Membrane ; metabolism ; Mice ; Patch-Clamp Techniques ; Potassium Channels, Calcium-Activated ; radiation effects ; Radiation, Ionizing ; Wound Healing ; radiation effects

Bone Diseases, Developmental ; surgery ; Female ; Femur ; pathology ; surgery ; Fibrosis ; surgery ; Humans ; Middle Aged

Peptide cyclization, a pivotal approach to modifying linear precursors of proteins and pepticles, has been used to enhance their biological activities and serum stabilities. Recently, sortase A (SrtA) from Staphyloccus aureus becomes a promising new technology for efficiently incorporating site specific modifications into proteins, conjugating the cell surface and cyclizing the linear peptides. In this study, we constructed two recombinant expression systems, one with chitin binding domain and the other with six-histidine tag and chitin binding domain on the N-terminal of SrtA, separately. The results of enzymatic kinetics indicate that the two recombinant tags do not impair the transpeptidase activity of SrtA compared with the standard reaction reported under the same reaction condition. The two synthesized peptides with N-ternimal three glycines and C-terminal penta-amino acid motif, LPETG, were cyclized using immobilized and recycled SrtA. The SrtA-based cyclization promises to represent a simple method for easy and efficient enzymatic synthesis of large cyclic peptides.
Aminoacyltransferases ; metabolism ; Bacterial Proteins ; metabolism ; Cyclization ; Cysteine Endopeptidases ; metabolism ; Enzymes, Immobilized ; metabolism ; Kinetics ; Peptides ; metabolism ; Peptides, Cyclic ; biosynthesis ; Staphylococcus aureus ; enzymology

OBJECTIVETo evaluate the microleakage of fiber post and core systems after high-speed handpiece preparation at different time points.

METHODSThe crowns of forty-five extracted human premolar were removed and the roots were endodontically treated. The samples were devided into five groups. Root canal preparation was performed on each premolar followed by fiber post cementation and core build up. Tooth preparation was applied at 5 min in group 1, at 15 min in group 2 and at 30 min in group 3 after post cementation. Five teeth with only 5 mm apical sealing were served as a positive control group, and ten with fiber post and core build-up but no coronal preparation were taken as a negative control group. Microleakage was evaluated using a fluid filtration system. The bonding interface was observed by scanning electronic microscope (SEM).

RESULTSThe microleakage was significantly increased after coronal preparation with high-speed handpiece. The negative control group has less leakage [(1.50 × 10(-6) ± 0.37 × 10(-6)) µl×min(-1)×Pa(-1)] than the groups with coronal preparation (P < 0.05); Group 1 leaked significantly more [(6.02 × 10(-5) ± 1.02 × 10(-5)) µl×min(-1)×Pa(-1)] than group 2 [(1.50 × 10(-5) ± 0.26 × 10(-5)) µl·min(-1)×Pa(-1)] and group 3 [(1.50 × 10(-5) ± 0.39 × 10(-5)) µl×min(-1)×Pa(-1)] did (P < 0.05). Corresponding to microleakage, the micro gaps between the resin cement and dentine in group 1 were wider than those in the other groups. The coronal section was wider than the apical part.

CONCLUSIONSHigh-speed handpiece had negative effects on microleakage of fiber post and core systems. Coronal preparation should be performed 15 min or more after post cementation.

Cementation ; Dental Bonding ; Dental Leakage ; Dentin-Bonding Agents ; Humans ; Microscopy, Electron, Scanning ; Post and Core Technique ; instrumentation ; Resin Cements ; Root Canal Preparation ; Time Factors

Objective To investigate the value of Habib 4X in hepatic resection. Methods The clinical outcome of 21 patients with liver disease who received liver resection at the Tianjin Third Central Hospital from November 2009 to April 2010 were retrospectively evaluated. All the operations were carried out by using Habib 4X. Results All patients received hepatectomy, including right hepatectomy in three patients, left hepatectomy in one patient, multiple segmentectomy in nine patients, single segmentectomy in seven patients and partial liver resection in one patient. All tumors were reseeted completely. The mean operation time was (50±25) minutes and the mean blood loss was(129±117)ml. No patient was transferred to ICU. Three patients were complicated with bile leakage, one with lymphatic leakage and four with pleural effusion, and they were cured by non-surgical treatment. There were no patients with postoperative hemorrhage, incision infection or hepatic failure. No mortality was observed. The mean postoperative hospital stay was(19±14)days. Conclusions Radiofrequency energy was applied along the margins of the tumor to create zones of necrosis before resection with a scalpel, offering hepatobiliary surgeons an additional method for performing liver resections with minimal blood loss, low morbidity and mortality rates. As for malignant tumors, minor or major liver resection assisted by Habib 4X is safe, and it can reduce the chance of positive incisal margin.

OBJECTIVETo observe the clinical therapeutic effect of Nuzhen Yunyu Decoction (NYD, a Chinese recipe for nourishing blood and reinforcing Shen) and its influence on the hemodynamic parameters in ovarian and uterine arteries.

METHODSSixty-eight patients were randomly divided into two groups at the ratio of 2:1, 45 in the TCM group treated with Chinese medicine and 23 in the control group treated with clomiphene citrate. Menstrual cycle were taken as the indexes for clinical observation; basal body temperature, cervical mucus, vaginal exfoliative cells, serum hormones and B ultrasonic examination were taken as the indexes for ovulation and pregnancy assessment. The hemodynamic parameters of uterus and ovary were determined by using color Doppler ultrasonography, and the growth of follicles and ovulation, thickness of uterine endometrium were also monitored continuously.

RESULTSResults of 3 cycles treatment and 1 year follow-up study showed that the ovulation promoting rate, pregnancy rate and abortion rate in the two groups were similar, but the treated group showed better effects than that of control group, in such aspects as regulating menstruation, promoting growth and development of follicle, strengthening endometrium, improving blood supply and circulation of uterine and ovary (P < 0.05, P < 0.01).

CONCLUSIONNYD has the effects of ovulation promotion and holistic regulation of reproductive system.

Adult ; Anovulation ; drug therapy ; Drugs, Chinese Herbal ; therapeutic use ; Female ; Hemodynamics ; Humans ; Infertility, Female ; drug therapy ; etiology ; Ovary ; blood supply ; Ovulation Induction ; Phytotherapy ; Uterus ; blood supply ; Yin Deficiency ; drug therapy

·Age-related macular degeneration (AMD) and retinitis pigmentosa (RP) are common outer retinal degenerative problems, which are also the predominant causes of most blinding retinal diseases. Retinal prosthesis is a promising solution for such photoreceptor degeneration diseases.Most of current concepts for a retinal prosthesis are based on neuronal electrical stimulation. In the past twenty years, retinal prosthesis has been developed in two different directions: epiretinal prosthesis and subretinal prosthesis. Each prosthesis technique has its advantages and disadvantages. For epiretinal prosthesis, it is easier to be implanted and has the advantage of keeping most of the electronics in the vitreous cavity, off the retinal surface, which greatly helps in dissipating the heat generated by the implant device. In this paper, a brief overview of retinal prostheses concepts is introduced. After that, several important aspects of epiretinal electrical stimulation will be discussed. Moreover, some practical epiretinal prosthesis devices developed by researchers in United States, Germany and Japan in the past have been reviewed. We hope that the devices will be used widely in the near future.

AIMTo explore the effect of central serotonin (5-hydroxytryptamine, 5-HT) on gastric motility in rabbit and to analysis its mechanism.

METHODSIntracerebroventricular (icv) microinjection of drugs were used. The frequency and the amplitude of contractions of gastric motility were recorded.

RESULTS(1) Injection (icv) of 25 microg 5-HT increased the amplitude of contractions and decreased the frequency of gastric motility. (2) The effects of 5-HT were inhibited by injection (icv) of atropine, but intravenous(iv) injection of atropine could only block the increase effect of 5-HT on intragastric pressure. After injection (icv or iv) of phentolamine or propranolol, the effects of 5-HT on gastric motility were not changed markedly. (3) Microinjection (icv) of naloxone or diphenhydramine inhibited the inhibitory effect of 5-HT on the frequency of gastric contractions, and the diphenhydramine reversed the increase effect of 5-HT on intragastric pressure. (4) Vagotomy abolished the effects of 5-HT completely.

CONCLUSIONThere may be different nerve mechanisms in regulation of central 5-HT on the frequency and amplitude of contractions of gastric motility. The increase effect of 5-HT on intragastric pressure is medicated by the cholinergic system in brain, and histamine may be one of the important element on the effect of 5-HT. The cholinergic fibers in vagus nerve transmit the effect. The inhibitory effect of 5-HT on the frequency of contractions is also medicated by activating the cholinergic system in brain, enkephalin and histamine are also involved, and it is transmitted via noncholinergic and nonadrenergic fibers in vagus nerve.

Animals ; Gastrointestinal Motility ; drug effects ; physiology ; Lateral Ventricles ; Rabbits ; Serotonin ; administration & dosage ; pharmacology

The gene coding for beta-glycosidase (EC3.2.1.21) from Thermus nonproteolyticus HG102 has been cloned and expressed in E. coli. The gene open reading frame was 1311 bp and it codes for 436 amino acids. The deduced amino acid sequence of the enzyme showed identity with members of glycosyl hydrolase family I. The enzyme had high content of hydrophobic amino acid (Ala 12.8%, Leu 10.9%), Arg(9.6%), Glu(9.4%) and Pro(8.0%), but low content Cys(0.45%) and Met (0.9%). From the alignment of enzyme amino acid sequence with other glycosyl hydrolase family I members, Glu164 and Glu338 were predicated as the proton donor and nucleophile group. The DNASTAR program was used to predict the secondary structure. According to the Chou-Fasman model, the enzyme has 41.4% of alpha-helics, 16.2%, beta-strands, 14.4%, beta-turns. 14 of the 35 Pro were located at the second sites of beta-turns. Hydrophobic interaction, ion bond, alpha-helics and Pro had important contribution to Tn-gly thermostability.
Amino Acid Sequence ; Cloning, Molecular ; Escherichia coli ; genetics ; Glycoside Hydrolases ; biosynthesis ; classification ; genetics ; Hot Temperature ; Molecular Sequence Data ; Open Reading Frames ; genetics ; Phylogeny ; Protein Structure, Secondary ; physiology ; Recombinant Proteins ; biosynthesis ; genetics ; Sequence Analysis, DNA ; methods ; Sequence Homology ; Thermus ; enzymology ; beta-Glucosidase

Objective　To study the effects of irradiation and W11-a12，a kind of repair-promoting drug，on anion-selective channel in membranes of mouse peritoneal macrophage. Methods　The activity of anion-selective channel was recorded from cell-attached patches with patch clamp techniques． Results　The effects of irradiation on anion-selective channel in membranes of peritoneal macrophage included：①decreasing the mean number of activated channels by the presence of zymosan; ②prolonging the mean time from stimulus to the opening of channels; ③depressing the opening of channels by decreasing open-state probability，shortening open-time and prolonging close-time． The effects of irradiation could partly be depressed by W11-a12. Conclusion　Irradiation will depress the anion-selective channel of peritoneal macrophage, which may be an important way to depress the function of macrophage．