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

In order to provide a new method for treating proliferative vitreoretinopathy (PVR), the effects of anti-proliferation and apoptosis induction of inhibitors of telomerase and heat shock protein 90 (Hsp90) on the cultured retinal pigment epithelial (RPE) cells were investigated. The rate of apoptosis cells was measured by using TUNEL on the cultured RPE cells, the co-cultured RPE cells with inhibitor of telomerase (camptothecin) or the co-cultured RPE cells with inhibitor of Hsp90 (geldanamycin). The cell proliferation status was measured in the above three groups by using MTT method. The rate of apoptosis in the RPE cells co-cultured with camptothecin or geldanamycin was increased remarkably (P<0.05). MTT showed the rate of growth inhibition was 8.4 %, 32.3 % and 72.3 % at the concentrations of camptothecin 1 μmol/L, 5 μmol/L, 10 μmol/L, respectively, and 6.5 %, 30.9 %, 71.9 % at the concentrations of geldanamycin 1 μmol/L, 5 μmol/L, 10 μmol/L, respectively. It was concluded that telomerase and Hsp90 can promote the proliferation of the cultured RPE cells, while the inhibitor of them can induce apoptosis and inhibit the growth of the RPE cells.

In order to provide a new method for treating proliferative vitreoretinopathy (PVR), the effects of anti-proliferation and apoptosis induction of inhibitors of telomerase and heat shock protein 90 (Hsp90) on the cultured retinal pigment epithelial (RPE) cells were investigated. The rate of apoptosis cells was measured by using TUNEL on the cultured RPE cells, the co-cultured RPE cells with inhibitor of telomerase (camptothecin) or the co-cultured RPE cells with inhibitor of Hsp90 (geldanamycin). The cell proliferation status was measured in the above three groups by using MTT method. The rate of apoptosis in the RPE cells co-cultured with camptothecin or geldanamycin was increased remarkably (P<0.05). MTT showed the rate of growth inhibition was 8.4 %, 32.3 % and 72.3 % at the concentrations of camptothecin 1 μmol/L, 5 μmol/L, 10 μmol/L, respectively, and 6.5 %, 30.9 %, 71.9 % at the concentrations of geldanamycin 1 μmol/L, 5 μmol/L, 10 μmol/L, respectively. It was concluded that telomerase and Hsp90 can promote the proliferation of the cultured RPE cells, while the inhibitor of them can induce apoptosis and inhibit the growth of the RPE cells.

The expression of transforming growth factor-β1 (TGF-β1) in placental tissue of pregnancy-induced hypertension (PIH) and the relationship between the level of expression of TGF-β1 and the amount of vascular cell adhesion molecule-1 (VCAM-1) in serum was studied. Immunohistochemistry ABC was used to detect the expression and distribution of TGF-β1 in placental tissues in 40 PIH women and 20 normal pregnancy women. High resolution pathological image analysis system was used to determine the quality of TGF-β1. The VCAM-1 in serum was examined by enzyme linked immunoabsorbent assay (ELISA). The results showed that TGF-β1 could be express in syncytiotrophoblast. The levels of TGF-β1 expression in placental tissues of the patients with moderate and severe PIH were significantly higher (P＜0.05), while the serum VCAM-1 was significantly lower than in normal group (P＜0.01). There was a significant positive correlation between the expression of TGF-β1 in placental tissues and the serum VCAM-1 (r=0. 969, P＜0.01). It was concluded that the level of TGF-β1 expression in PIH was increased and was positively correlated with the amount of serum VCAM-1, indicating that they might be involved in the pathogenesis of PIH.

In order to further investigate the mechanisms of action of berberine (Ber), we assessed the effects of Ber on the mRNA expression of nitric oxide synthases (NOS) in rat corpus cavernosum. After incubation with Ber for 1 or 3 h respectively, the levels of NOS mRNA were examined by reverse transcription polymerase chain reaction (RT-PCR). Our results showed that there were iNOS and eNOS mRNA expressions in rat corpus cavernosum. Ber enhanced eNOS mRNA expression in rat penis, but exhibited no effect on the expression of iNOS mRNA (P＞0.05). The present study indicated that the relaxation of Ber involved the NO-cGMP signal thansduction pathway. The enhancing effect of Ber on eNOS mRNA expression might associated with its relaxation of corpus cavernosum.

The P2X7 receptor mRNA and proteins in guinea-pig dorsal root ganglia (DRG) were studied by using RT-PCR and immunohistochemistry. The co-localization of P2X7 receptor with four cytochemical markers, the neurofilament protein NF200, S100, substance P and isolectin B4 (IB4) binding glyco-conjugates, were also examined. It was found that P2X7 receptor immunoreactivity (P2X7R-IR) was present mostly in large- and medium-sized DRG neurons (62 %±9 % and 36 %±6 % respectively in all P2X7R-IR neurons). All the P2X7R-IR neurons were also NF200 and S100 immunopositive. However, in a small number of NF200 or S100 immunopositive neurons no P2X7R-IR was detectable. All the IB4-positive or substance P-immunopositive neurons had no P2X7R-IR. These results demonstrate that P2X7 receptors are expressed in a large subpopulation of DRG neurons and they may play a role in the transduction of specific peripheral sensory signals.

To evaluate the effect of wild-type p53 gene on the growth and radiotherapeutic sensitivity of human glioma cells, plasmid PC53-SN3 carrying wild-type p53 gene was transfected into U251cells. p53 gene expression in transfected cells was detected by RT-PCR, and the cell growth inhibition and apoptosis in the absence or presence of irradiation were assessed by MTT and flow cytometry. The transfection of p53 gene into U251 cells was confirmed by RT-PCR. MTT showed that p53 gene alone induced strong inhibitory effect on the growth of U251 cells (inhibition rate (IR):(79.60±5.69) %). The killing effect of irradiation alone on U251 cells was not strong (IR: (17.06±4.35) %, (17.39±1.67) %, (18.73±4.68) %) and increased with the irradiation doses (3,6, 9 Gy). When combined treatment of wild-type p53 gene transfection and irradiation was used,the effect was significantly increased (IR:(80.60±5.35) %, (90.30±1.67) %, (91.30±2.01)%). The apoptosis rate of U251 cells induced by p53 gene transfection was 17.38 %. The rate induced by irradiation increased (4. 61%, 4. 84 %, 5.40 %) with the irradiation doses (3, 6, 9Gy). The apoptosis rate was also significantly increased (17.80 %, 20.03 %, 22.34%) after combined treatment of p53 and irradiation with different doses (3, 6, 9 Gy). It is concluded that wildtype p53 gene and irradiation could result in synergistic inhibitory effect on the growth of human glioma cells.

Bile acids participated in regulation of many physiological functions in the human body. Transporters in liver and intestinal play an important role in maintaining the enterohepatic circulation and bile acid homeostasis. With the rapid development of molecular biology in recent years, there has been great progress toward cloning and identifying the individual bile acid transporters and explaining their complex regulation. Bile acid transporters were regulated by various factors including bile acids, nuclear receptors, transcription factors, hormones, etc., which influence their protein expression, cell location and transport activities. This article reviews the research progress of bile acid transporters for the purpose of providing references for the mechanism research of bile acid transporter related disorders and drug development.

As a major flavonoid in the leaves of Ampelopsis grossedentata, dihydromyricelin has attracted wide attention in recent years. The pharmacological effect of the dihydromyricelin is clear, but the limitation on the clinical application of this drug comes from its chemical properties and low bioavailability. Nowadays, researching on advanced pharmaceutical preparation and new dosage forms in order to improve its chemical properties has become hot spots. Based on the review of related literatures, we discussed the research progress on advanced pharmaceutical preparation and new dosage forms of dihydromyricelin, such as liposomes, microcapsules, microemulsions, solid dispersion, inclusion compound, floating gastroretentive drug, etc. The main purpose is to point out the shortages of existing research and provide a reference for further study.

To evaluate the effects of wild-type p53 gene on the growth and chemotherapeutic sensitivity of human glioma cells, plasmid PC53-SN3 carrying wild-type p53 gene was transfected into U251 cells. p53 gene expression in transfected cells was detected by RT-PCR, the cell growth inhibition and apoptosis in either the absence or the presence of cisplatin was assessed by MTT and flow cytometry. The transfection of p53 gene into U251 cells was confirmed by RT-PCR. MTT showed that p53 gene by itself induced strong inhibition effect on the growth of U251 cells [inhibition rate, IR (79.60 +/- 5.69)%]. The killing effects of cisplatin by itself on U251 cells was not strong [IR (19.40 +/- 6.69)%, (24.41 +/- 2.68)%, (51.84 +/- 13.38)%, (66.22 +/- 5.02)%] and increased with the increase of cisplatin concentration (1, 2, 4, 8 micrograms/ml). When combined treatment of wild-type p53 gene transfection and cisplatin was used, that was significantly increased [IR (91.64 +/- 1.00)%, (94.98 +/- 1.67)%, (95.32 +/- 2.01)%, (95.65 +/- 1.00)%]. The apoptosis rate of U251 cells induced by p53 gene transfection was 17.38%. That induced by cisplatin increased (5.71%, 5.93%, 6.27%, and 6.81%) with the increase of cisplatin concentration (1, 2, 4, 8 micrograms/ml). The apoptosis rate was also significantly increased (23.50%, 23.54%, 23.89%, and 28.88%) after combined treatment of p53 and cisplatin with different concentration (1, 2, 4, 8 micrograms/ml). It is concluded that wild-type p53 gene and cisplatin could result in synergistic inhibition effects on the growth of human glioma cells.
Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Cell Division ; drug effects ; Cell Line, Tumor ; Cisplatin ; pharmacology ; Drug Resistance, Neoplasm ; genetics ; Gene Expression Regulation, Neoplastic ; genetics ; Genes, p53 ; genetics ; Glioma ; genetics ; pathology ; Humans ; Recombinant Fusion Proteins ; physiology