Background: Aap, aggR, astA have been found to play important roles in diarrheal pathogenecity of enteroaggregative (EAEC). Objective: (1) To determine the distribution of aap, aggR, astA in EAEC. (2) To compare the distribution of aap, aggR, astA in EAEC isolated from healthy children and children with diarrhea. Subject and methods: \r\n', u'86 strains of EAEC isolated from children under 5 living in Hanoi, have been screened by PCR with specific primers. Results: Aap was found at the highest prevalence of 96.5%, aggR (79.1 %) and astA (60.5%). 37.2% of strains had all of aap, aggR and astA. None of strains was shown negative with these genes. Distributive rate of aap, aggR, astA in EAEC strains isolated from children with diarrhea was higher than EAEC strains isolated from healthy children. However, this difference was not statistically significant. Nearly 100% of the EAEC strains isolated from children with diarrhea had aap gene. The rate of aggR and astA was lower. Among children aged 0-24 months and children aged 25-60 months, distribution of these three genes was not different with statistical significance Conclusion: This finding has contributed to understanding the distribution of aap, aggR and astA of EAEC\r\n', u'\r\n', u'
Diarrhea ; Oligopeptides ; Escherichia coli Proteins

N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) is an endogenous short peptide produced through the continuous hydrolysis of Thymosin β4 by meprin-α and prolyl oligopeptidase. It has the functions of immune regulation, promoting angiogenesis, tumorigenesis and anti-fibrosis in organs. In this paper, according to some our research results and related literatures in recent years, a review of Ac-SDKP research progress was written.
Humans ; Oligopeptides ; Cell Transformation, Neoplastic

OBJECTIVE: To investigate the effects of the Arg-Gly-Asp polypeptedes (RGD) peptides-modified porous tantalum surface on osteoblasts morphology and expressions of osteogenesis factors, and to evaluate RGD peptides promotes junctura ossium of tantalum-bone interface in vivo. METHODS: RGD peptides of different concentrations (1 g/L, 5 g/L, and 10 g/L) were loaded to porous tantalum slices with a diameter of 10 mm and a thickness of 3 mm by physical absorption. The 3rd generation of MG63 cells were co-cultured with tantalum and divided into 4 groups: Ta-cells (control) group, 1 g/L cells/Ta/RGD group, 5 g/L cells/Ta/RGD group, and 10 g/L cells/Ta/RGD group. Porous tantalum compo-sites and osteoblasts-tantalum interface were observed by scanning electron microscopy. The adhesion rate of osteoblasts was detected and immunocytochemistry was used to detect the expressions of filamentous actin (F-actin), osteocalcin (OC) and fibronectin (FN). RESULTS: The scanning electron microscope (SEM) revealed that osteoblasts distributed on the surface of porous tantalum and secreted extracellular matrix on outside and inner of micro-pores. The osteoblasts adhesion rate on porous tantalum modified with RGD was higher than that in the unmodified porous tantalum at the end of 24, 48, and 72 hours. The best adhesion effect was got in 5 g/L cells/Ta/RGD group at hour 48 [(68.07±3.80) vs. (23.40±4.39), P<0.05]. The results of immunocytochemistry showed that the expressions intensity of F-actin, OC and FN in osteoblasts on porous tantalum modified groups with RGD were stronger than that in the unmodified groups, and the expressions of 5 g/L cells/Ta/RGD group were significantly higher than those in the 10 g/L group and 1 g/L group [OC: (18.08±0.08) vs. (15.14±0.19), P<0.05; (18.08±0.08) vs. (14.04±0.61), P<0.05. FN: (24.60±0.98) vs. (15.90±0.53), P<0.05; (24.60±0.98) vs. (15.30±0.42), P<0.05. F-actin: (29.20±1.31) vs. (24.50±1.51), P<0.05; (29.20±1.31) vs. (16.92±0.40), P<0.05]. Correspondingly F-actin in osteoblasts was showed in longitudinal arrangement, and the expressions intensity was stronger than those OC and FN. CONCLUSION The RGD peptides is beneficial to enhance adhesion of osteoblast, spreading and reorganization of cytoskeleton on porous tantalum surface and improve the interface morphology, further promoting osteoblasts-tantalum conjunctive interface osseointegration.
Cell Adhesion ; Oligopeptides ; Osteoblasts/physiology* ; Osteogenesis ; Tantalum

OBJECTIVEThis study is conducted to explore new methods to perform surface biomodification of titanium implants and improve osteogenic efficiency.

METHODSAn RGD peptide and chitosan (CS) were combined by acylation reaction, forming RGD-CS. An RGD-CS/pDNA complex was subsequently prepared using a complex coacervation method and grafted on a pure titanium surface after physical and biochemical treatments were performed. The chemical structural characteristics of RGD-CS were evaluated using an infrared spectrometer and an elemental analyzer. The shape of this complex was then assessed by gel electrophoresis combined with atomic force microscopy. The grafting effect of this complex on the titanium surface was detected by EB staining.

RESULTSCS and RGD peptides were coupled by an amide bond. The RGD-CS/pDNA complex was completely composited at N/P > or = 2. Atomic force microscopy results showed that the morphology of this complex was mainly spherical. EB staining experiments showed that this complex was successfully grafted on the titanium plate.

CONCLUSIONRGD peptide-modified CS can be used as a titanium implant surface plasmid package carrier of pDNA.

Chitosan ; Dental Implants ; Microscopy, Atomic Force ; Oligopeptides ; Plasmids ; Titanium

A novel synthetic hexapeptide (SFKLRY-NH2) that displays angiogenic activity has been identified by positional scanning of a synthetic peptide combinatorial library (PS-SPCL). This study was carried out to investigate the irritation of the SFKLRY-NH2 on the skin. The tests were performed on the basis of Korea Food and Drug Administration (KFDA) guidelines. In results, cell toxicity is not appeared for SFKLRY-NH2 in HaCaT cells and B16F10 cells. SFKLRY-NH2 induced no skin irritation at low concentration (10 microM), mild irritation at high concentration (10mM). We consider that this result is helpful for saying about the safety of SFKLRY-NH2 in clinical use.
Korea ; Oligopeptides ; Peptide Library ; Skin ; United States Food and Drug Administration

The enzymatic synthesis of a tetrapeptide Phac-Met-Gly-Trp-Met-OEt, a fragment of the cholecystokinin C-terminal octapeptide CCK-8, was reported. This fragment was synthesized by coupling Phac-Met-OEt with Gly-OMe, Trp-OMe and Met-OEt successively. These three steps were catalyzed by alpha-chymotrpsin, Papain and alpha-chymotrpsin respectively. The results of FAB-MS showed that all the products had the correct molecular mass.
Catalysis ; Chymotrypsin ; *Oligopeptides ; Papain ; Peptide Fragments ; Sincalide/*chemical synthesis

The enzymatic synthesis of a tetrapeptide Phac-Met-Gly-Trp-Met-OEt, a fragment of the cholecystokinin C-terminal octapeptide CCK-8, was reported. This fragment was synthesized by coupling Phac-Met-OEt with Gly-OMe, Trp-OMe and Met-OEt successively. These three steps were catalyzed by alpha-chymotrpsin, Papain and alpha-chymotrpsin respectively. The results of FAB-MS showed that all the products had the correct molecular mass.
Catalysis ; Chymotrypsin ; Oligopeptides ; Papain ; Peptide Fragments ; Sincalide ; chemical synthesis

OBJECTIVE: To study the effect of PR-957 on the formation of A1 reactive astrocytes. METHODS: The cerebral cortices of 1-day-old female rats were obtained and cultured for primary astrocytes. These cells were divided into 3 groups: control, lipopolysaccharide (LPS), and LPS+PR-957. The LPS group was treated with LPS (at a concentration of 5 μmol/L) for 48 hours; the LPS+PR-957 group was treated with PR-957 (at a final concentration of 200 nmol/L) for 1 hour and then LPS for 48 hours. Enzyme-linked immunosorbent assay was used to determine the expression of complement 3 (C3, a marker for A1 reactive astrocytes) and tumor necrosis factor alpha (TNF-α). Quantitative real-time PCR was used to determine the relative mRNA expression of glypican-6 (GPC6), SPARC-like 1 (SPARCL1), and lipocalin-2 (LCN2). All the above experiments were repeated three times independently. RESULTS: C3 expression was almost not observed in the control group, but was observed in both the LPS group and the LPS+PR-957 group, with significantly lower expression observed in the LPS+PR-957 group (P<0.05). The expression of TNF-α was consistent with that of C3. Compared with the control group, the LPS and the PS+PR-957 groups had significantly reduced mRNA expression levels of GPC6 and SPARCL1 but significantly increased mRNA expression level of LCN2 (P<0.001). Compared with the LPS group, the LPS+PR-957 group had significantly increased mRNA expression levels of GPC6 and SPARCL1 but significantly reduced mRNA expression level of LCN2 (P<0.001). CONCLUSIONS LPS can induce the transformation from astrocytes to A1 reactive astrocytes, and PR-957 can inhibit the formation of LPS-induced A1 reactive astrocytes.
Animals ; Astrocytes ; Female ; Lipopolysaccharides ; Oligopeptides ; Rats ; Tumor Necrosis Factor-alpha

OBJECTIVE: To explore the clinical effects on primary dysmenorrhea treated with moxibustion at Shenque (CV 8) and warm needling at Guanyuan (CV 4) and Sanyinjiao (SP 6). METHODS: A total of 120 patients with primary dysmenorrhea were randomized into an observation group and a control group, 60 cases in each one. In the control group, the warm needling technique was used at Guanyuan (CV 4) and Sanyinjiao (SP 6). In the observation group, besides the same treatment as the control group, moxibustion was added at Shenque (CV 8). The treatment was given for 4 menstrual cycles consecutively. Before and after treatment, the score of the severity and the score of the total frequency in the retrospective scale of dysmenorrhea symptoms as well as the score of the visual analog scale (VAS) were recorded and compared in the patients between the two groups. Additionally, the safety of the two therapeutic methods was evaluated. RESULTS: After treatment, the score of severity and the score of total frequency as well as VAS score of menstrual pain were all reduced as compared with those before treatment in the patients of the two groups (all <0.05). The scores in the observation group were more obvious as compared with the control group (all <0.05). Regarding the safety evaluation, the difference was not significant between the two groups (>0.05). CONCLUSION The combined treatment of moxibustion at Shenque (CV 8) with the warm needling technique at Guanyuan (CV 4) and Sanyinjiao (SP 6) achieves the better clinical effects on primary dysmenorrhea as compared with the simple application of the warm needling technique at Guanyuan (CV 4) and Sanyinjiao (SP 6). This therapy is safety in clinical practice.
Acupuncture Points ; Dysmenorrhea ; therapy ; Female ; Humans ; Moxibustion ; Oligopeptides ; Retrospective Studies

OBJECTIVETo evaluate the effects of antiarrhythmic peptide (AAP10) on ventricular arrhythmias in rabbits with healed myocardial infarction (OMI).

METHODSThirty rabbits were randomly divided into three groups (n = 10 each): Sham group, left thoracotomy was performed without coronary ligation; OMI group and OMI + AAP10 group, the circumflex coronaries were ligated. Three months post operation, the electrophysiological and antiarrhythmic effects of AAP10 were assessed in the arterially perfused rabbit left ventricular wedge preparation. Sham and OMI group were perfused with Tyrode's solution and OMI + AAP10 group was perfused with Tyrode's solution + AAP10 (80 nmol/L). Transmembrane action potentials were recorded simultaneously from endocardium and epicardium together with a transmural ECG by use of 2 separate intracellular floating microelectrodes. The stimulus-response-interval (SRI) of the epicardium and the incidence of ventricular tachycardia (VT) were observed. Whole heart and left ventricular weights, the left ventricular thickness at infarct border zone were measured.

RESULTSWhole heart and left ventricular weights as well as the left ventricular thickness at the infarct border zone significantly increased post infarction. VT was induced in 8 out of 10 rabbits in OMI group and in 2 out of 10 rabbits in OMI + AAP10 group (P < 0.05). SRI was also significantly shortened in OMI + AAP10 group compared to OMI group [SRI-1: (20.59 +/- 0.79) ms vs. (28.71 +/- 0.55) ms; SRI-2: (30.42 +/- 0.74) ms vs. (38.67 +/- 0.49) ms, all P < 0.01]. However, the action potential morphology and duration were similar between OMI and OMI + AAP10 groups.

CONCLUSIONThe antiarrhythmic peptide (AAP10) can increase gap junctional intercellular conductance without affecting the action potential morphology and duration and decrease the incidence of inducible ventricular tachycardia.

Animals ; Arrhythmias, Cardiac ; etiology ; prevention & control ; Male ; Myocardial Infarction ; complications ; physiopathology ; Oligopeptides ; pharmacology ; Rabbits ; Random Allocation