Adenoviridae ; genetics ; Cell Death ; Genetic Vectors ; HT29 Cells ; Humans ; Interleukins ; biosynthesis ; genetics ; RNA, Catalytic ; biosynthesis ; genetics ; RNA, Messenger ; metabolism ; Recombinant Proteins ; biosynthesis ; genetics ; Transfection ; Vascular Endothelial Growth Factor A ; metabolism

Purpose The research was conducted to evaluate the stability of N-terminal site-specific PEGylated uricase. Methods The enzyme activity is used as an index to evaluate the thermal stability (at 4-80 ℃) , the pH stability, the ability of avoiding the trypsin digestion and half-life in vivo of PEG-uricase, then it is compared with uricase. Results PEGylated uricase is thermally more stable than uricase between 4 ℃ and 60 ℃, but at 70 ℃, the enzyme activity of both PEG-uricase and uricase decreases sharply. In the test of pH stability, the curve of uricase shows an obvious decrease of enzyme activity at 5 .2-6.0 and 9.2-10.0. The behavior of PEG-uricase indicates that the destabilizing was prevented effectively by PEGylation. The test of anti-trypsin digestion suggests that PEG-uricase retains 70% of its enzyme activity,but uricase only 20% ,200 minutes after being reserved in trypsin solution. Stability in vivo indicates that the half-life of PEG-uricase is 1 530 min and uricase, only 45 min. Conclusion PEGylated uricase has improved thermal stability, the pH stability, ability of protecting from trypsin digestion and stability in vivo.

Objective To evaluate the changes of cerebrospinal fluid dynamics of Chiari malformation type I associated syringomyelia patients with phase-contrast MRI (PC-MRI).Methods Thirty cases diagnosed with Chiari malformation type Ⅰ associated with syringomyelia clinically underwent cisterna plasty treatment.Cerebrospinal fluid dynamics changes were measured before 24 h and 6 months after operation with PC-MRI.The stroke volume (SV),mean flow (MF),regurgitation fractions (RF) and the maximum peak flow velocity (Vmax) were analyzed.Results After operation,PC-MRI showed SV and MF increased,the bidirectional Vmax decreased,which had statistical difference compared with those of preoperation (all P＜0.05),and the C2-3 level was the most obvious.Conclusion PC-MRI can quantitative analysis of preoperative and postoperative changes of cerebrospinal fluid flow and peak velocity.

Purpose To evaluate the feasibility of magnetic resonance T2 values in diagnosing hepatic fibrosis (HF).Materials and M1etdheds The models of HF were induced in rats by repetitive dosing of carbon tetrachloride.The stage of hepatic fibrosis (S),grade of inflammation (G) and degree of fatty liver (F) for the HF model animals and their normal controls were evaluated by pathology.The relationship between T2 values and liver fibrosis was analyzed by using multiple echo gradient spin echo sequences.Results According to the stage of hepatic fibrosis,the HF model rats were staged into S1-S4.The grade of inflammation of the HF model rats was G0 or G1,and the degree of fatty liver was F3 or F4,both of which had no statistical differences among the HF model rats at different fibrosis stages (P＞0.05).The T2 values for all rats including normal control rats in the stage of liver fibrosis from S0 to S4 were (38.27±1.45) ms,(42.08±2.63) ms,(45.93±3.61) ms,(50.23 ± 2.23) ms and (57.79± 5.40) ms,respectively,with a significant difference (F=31.903,P＜0.01).Except the T2 values had no significant difference between the S0 and S 1 stages (P＞0.05),the pairwise comparisons of the T2 values between the rest stages were statistically significant (P＜0.01).The T2 values were positively correlated with the stages of hepatic fibrosis (rs=0.921,P＜0.01).Conclusion The T2 value can quantitatively reflect the degree of hepatic fibrosis.

Medical care on the battlefield is the core and basis of echelons of care.This review summarizes the background and characteristics of medical care units on the battlefield from the birth and growth of mobile army surgical hospitals before being replaced by forward surgical teams and combat support hospitals, since the United States Armed Forces began to lead the world military revolution during and after the World WarⅡ.Quick adaptation to the combat envi-ronment and the combat modes is the main reason that medical care units on the battlefield are adjusted continuously.This paper may provide some ideas for the development of our medical care units on the battlefield in the future.

Doctor WANG Zhi-zhong in the Southern Song Dynasty proposed the acupoint view of "location of disease", which explained the connotation of acupoints from the angle of clinic. Its meaning included two levels, one level meant pathological change on the body surface, that was the location of acupuncture diagnosis-treatment, and the other one indicated that the body surface which was the reflecting point of pathological change on the distal area or inside the body was the location of acupuncture diagnosis-treatment. The specific connotations of clinical acupoints were: location of pathogenic factors or reflection of pathogenic factors, regularity between acupoints un- der disease and specific organ, morphological differences and positioning variability after acupoints under disease, and acupoints examination, diagnosis and treatment.
Acupuncture Points ; Acupuncture Therapy ; history ; China ; History, Ancient ; Humans ; Medicine in Literature ; Meridians

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

AIM: To study the effect of wild-type p53 gene on the differentiation, apoptosis and expression of scavenger receptor CD36 in U937 cells. METHODS: Recombinant adenovirus vector with wild-type p53 gene was constructed and used to transfect U937 cells. With the expression of wild-type p53 gene following adenoviral infection, transfected U937 cells were largely promoted to differentiate into macrophages. RESUITS: Trypanblue-staining test demonstrated that the percentage of positive cells increased from (14.2±5.5)% to (64.6±9.2)% and nitroblue tetrazolium (NBT) reduction test reached similar results (6.3±1.8)% vs (49.7±12.6)%. Furthermore, CD36 mRNA was up-regulated as confirmed by RT-PCR. The increased expression level of CD 36 was also detected by flow cytometry analysis. CONCLUSION: These results suggest that wild-type p53 gene can affect U937 cells differentiation and apoptosis, up-regulate expression of scavenger receptor CD36. It may have a potential significance on atherogenesis.

To investigate the effect and possible mechanism of echinacoside-containing serum on the osteogenic differentiation in rat bone marrow mesenchymal stem cells. Rat bone marrow mesenchymal stem cells were cultivated by the whole bone marrow adherence method. The 3rd generation of cells were divided into 3 groups: the blank control group, the classic osteogenic-induced group and the 10% echinacoside-containing serum group. The expression of alkaline phosphatase and osteocalcin were detected by ELISA. The ex- pression of ZHX, protein was detected by Western blot technique. RT-PCR technique was used to detect the expression of ZHX₃mRNA. According to the result, the expressions of the alkaline phosphatase and osteocalcin in the classic osteogenic-induced group and the 10% echinacoside-containing serum group were significantly higher than that of the blank control group (P <0. 01). And expressions of the alkaline phosphatase activity and osteocalcin in the 10% echinacoside-containing serum group were significantly higher than that in the classic osteogenic-induced group (P < 0.01). Meanwhile, the classic osteogenic-induced group and the 10% echinacoside-containing serum group showed obviously higher ZHX₃ protain and mRNA expression than that of the black control group, with significant differences (P < 0.01); the 10% echinacoside-containing serum group showed obviously higher ZHX₃ protain and mRNA expression than that of the classic osteogenic-induced group, with a significant difference (P < 0.01). In conclusion, 10% echinacoside-containing serum can promote the differentiation of the bone marrow mesenchymal stem cells cultured in vitro. Its mechanism may be correlated with the increase in the ZHX₃expression.
Animals ; Cell Differentiation ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Female ; Glycosides ; blood ; pharmacology ; Homeodomain Proteins ; genetics ; metabolism ; Male ; Mesenchymal Stromal Cells ; cytology ; drug effects ; metabolism ; Osteogenesis ; drug effects ; Rats ; Rats, Sprague-Dawley ; Serum ; chemistry ; Transcription Factors ; genetics ; metabolism

Objective To characterize pancreatic perfusion in swines with experimental chronic pancreatitis(CP)by dynamic contrast-enhanced MRI and to correlate it with the severity of CP.Methods Twenty-two swines were randomly selected and made CP by ligation of main pancreatic duct.Six healthy swines served as control.MR perfusion study with dynamic contrast-enhanced MRl was carried out on the swines under anesthesia.The animals were euthanized after MR perfusion exam.The swines were divided into 4 groups according to the histological results of pancreas:normal group,group of CP of grade 1,group of CP of grade 2,and group of CP of grade 3.The maximum perfusion slope rate,the time-to-peak value and the maximum enhancement rate was compared between the groups using variance analysis,and the relationship between each perfusion parameters and severity of CP was made by correlative analysis.Results Twenty-one swines underwent MR perfusion study,including 7 swines in normal group,7 in group of grade 1 CP,3 in group of grade 2 CP,and 4 in group of grade 3 CP.On signal intensity time curve(SI-T)derived from MR perfusion weighted imaging,the m~imum slope rate was(10.88±1.20)%,(10.59±1.02)%,(6.67±1.31)%,and(5.48±1.97)%for normal swines,swines with grade 1 CP,swines with grade 2 CP and swines with grade 3 CP,respectively(F=20.51,P＜0.05).The time-to-peak value was(13.82±3.09)s,(12.31±5.52)s,(20.55±3.79)s and(37.26±14.56)s respectively(F=10.68,P＜0.05).The maximal signal enhancement rate was(62.95±20.20)%,(60.44±20.00)%,(46.33±22.70)%,and(67.65±32.66)%,respectively(F=0.53,P＞0.05).The highest slope value(r=-0.72,P＜0.05)and the time-to-peak(r=0.54,P＜0.05)of the SI-T curve were correlated to the severity of CP,respectively.However there was no linear correlation between the maximal signal enhancement rate and the severity of CP.Conclusion MR perfasion weighted imaging has a potential to diagnose and to grade experimental chronic pancreatitis.