Heparin, one of the common anticoagulants, is clinically used to prevent and treat venous thromboembolism (VTE). Though it has been the drug of choice for many advanced medical and surgical procedures with a long history, the adverse events, such as bleeding, heparin-induced thrombocytopenia (HIT), allergic reactions, follow. Therefore, low molecular weight heparins (LMWHs) and ultra low molecular weight heparins (ULMWHs), with lower molecular weights, higher anti-FXa activity, longer half-life times and lower incidence of adverse events than unfractionated heparin (UFH), were researched and developed. Fondaparinux, a chemically synthesized ULMWH of pentasaccharide, has the same antithrombin III (AT-III)-binding sequence as found in UFH and LMWH. In addition, AVE5026 and RO-14, another two ULMWHs, are obtained by selective chemical depolymerization. In this paper, we review the preparation process, pharmacological effects and clinical applications of fondaparinux, AVE5026 and RO-14.

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α₁-Adrenergic receptors (α₁-ARs), as one of the most important members of G protein-coupled receptors (GPCRs), can mediate lots of physiological responses of the sympathetic nervous system. Until now, α₁-ARs have been divided into at least three subtypes, α_1A, α_1B, and α_1D, which distribute in various tissues and organs. In this research, we designed and synthesized several napthalimide-based small-molecule fluorescent probes for α₁-ARs, which mainly contained two parts: the pharmacophore (quinazoline and phenylpiperazine) that binds to α₁-ARs and the fluorophore (naphthalimide) that labels the receptors with fluorescent properties. Moreover, some of these compounds demonstrated potent affinity to α₁-ARs and cell imaging potential.

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Rafflesia kerrii has been used in Thai traditional remedies for treatment of several diseases. However, scientific data particularly on biological activities of this plant is very rare. The present study explores an antioxidant activity of R. kerrii flower (RKF). Extracting solvent and extraction procedure were found to play an important role on the activity of RKF extract. The extract obtained from water-ethanol system showed higher antioxidant activity than that from water-propylene glycol system. Fractionated extraction using different solvents revealed that methanol fractionated extract (RM) possessed the highest antioxidant activity with Trolox equivalent antioxidant capacity (TEAC) and inhibitory concentration of 50% inhibition (IC50) values of approximately 39 mM/mg and 3 μg/mL, respectively. Phytochemical assays demonstrated that RM contained extremely high quantity of phenolic content with gallic antioxidant equivalent (GAE) and quercetin equivalent (QE) values of approximately 312 mg/g and 16 mg/g, respectively. Ultraviolet-visible spectroscopy (UV- VIS) and high-pressure liquid chromatography (HPLC) indicated that gallic acid was a major component. RM which was stored at 40°C, 75% RH for 4 months showed slightly significant change (p < 0.05) in phytochemical content and antioxidant activity with zero order degradation. The results of this study could be concluded that R. kerrii flower was a promising natural source of strong antioxidant compounds.

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Acetyl-11-keto-beta-BA (AKBA), a component of the gum resin of Boswellia serrata, has been recognized as a promising agent for the prevention of intestinal tumorigenesis. Aspirin, a non-steroidal anti-inflammatory drug (NSAID), has also been considered to have the activity against intestinal tumorigenesis. However, the prevention of colonic cancer is insufficient and no definitive recommendation has been made for clinic use. Herein, we compared the efficacy of AKBA with that of aspirin in an adenomatous polyposis coli intestinal neoplasia consecutive weeks. Mice were sacrificed by anesthetizing. The whole intestine was removed from each mouse. The number, size and histopathology of intestinal adenomatous polyps were examined under microscopy. The adenomatous polyps were removed for further analysis by the assays of western blotting and immunohistochemical staining. AKBA significantly prevented the formation of intestinal adenomatous polyps without toxicity to mice. Statistical analysis indicated that AKBA's activity both in the prevention of small intestinal and colonic polyps was more potently than aspirin. Histopathologic examination revealed that AKBA’s effect, that is the reduction of polyp size and degree of dysplasia, was more prominent in larger sized polyps, especially those originating in colon. These effects of AKBA were associated with its role in the induction of apoptosis in carcinomas. The assays of western blotting and immunohistochemistry staining indicated that the efficacy of AKBA might arise from its activity in the modulation of the Wnt/β-catenin pathway and NF-κB/COX-2 pathway in adenomatous polyps. Conclusion, AKBA by oral application prevented intestinal tumorigenesis more potential than aspirin.

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A ligustrazine (TMP) derivative, (E)-2-(2, 4-dimethoxystyryl)-3,5,6-trimethylpyrazine (DLJ14) was synthesized for the improvement of low bioavailability and short half-life of ligustrazine. We have observed potential reversal effects of DLJ14 on adriamycin (Adr)-resistant human myelogenous leukemia cells (K562/A02) and Adr-resistant human breast cancer cells (MCF-7/A) in vitro or in vivo in previous studies. The aim of the present study was to investigate the underlying molecular mechanism of DLJ14 and Adr combination treatment on Adr-resistant human breast cancer. Inhibition of cancer cell growth was estimated by 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Cell cycle distribution was analyzed by flow cytometry and apoptosis determined using Annexin V-FITC/propidium iodide (PI) double staining and Hoechst 33258 nuclear staining. The expression of proteins in the epidermal growth factor receptor (EGFR)/phosphatidylinositol-3 kinase (PI3K)/Akt survival pathway and mitochondrial-mediated apoptosis pathway were measured by Western blotting analysis. Results showed that DLJ14 and Adr combination treatment exhibited stronger inhibition of the survival of MCF-7/A cells than Adr treatment alone. This effect might be associated with its role in cell cycle arrest and apoptosis induction. DLJ14 combined with Adr induced cell cycle arrest in the G2/M-phase by activating p21^{wafl /cip1} and p53 in mitochondria and increased cleavage of caspase-9 and caspase-3, and Bax/Bcl-2 ratio. Mitochondrial membrane potential (MMP) disruption and cytochrome c (Cytc) release from mitochondria to cytosol suggested that apoptosis induction might be mediated by the mitochondrial pathway. Moreover, the combination of DLJ14 and Adr could down-regulate the expression of EGFR, p-EGFR, PI3K, and p-Akt in MCF-7/A cells. Overall, DLJ14 and Adr combination treatment may inhibit proliferation of Adr-resistant human breast cancer cells through inhibition of the EGFR/PI3K/Akt survival pathway and induction of apoptosis via the mitochondrial-mediated apoptosis pathway.

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Fibroblast growth factor-2 (FGF2) inhibits osteoblast mineralization, but the mechanism by which it does so is not fully understood. Matrix vesicles (MVs) play an essential role in the initiation of mineralization, so the current study examined the effect of FGF2 on the functioning of MVs to investigate this mechanism. This study found that FGF2 significantly inhibited differentiation and mineralization of osteoblast-like Saos-2 cells, as indicated by down-regulation of mRNA expression of the osteogenic master regulator runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP), and collagen 1 alpha 1 (Colla1), and by decreasing the formation of bone nodules. MVs were isolated from Saos-2 cells cultured in osteogenic medium supplemented with and without FGF2 and their presence was verified using electron microscopy and Western blotting. FGF2 markedly reduced the ALP activity of and in vitro mineralization by MVs. These findings suggest that FGF2 inhibits osteoblast mineralization by limiting the capacity of MVs.

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The use of adjuvant systemic chemotherapy for resectable liver metastases from colorectal cancer (CRC) is controversial because no trial demonstrated its benefit. We conducted the phase III trial to evaluate UFT/leucovorin (LV) for colorectal liver metastases (CRLM). The primary endpoint has not been available until 2014, we first report the feasibility and safety data of UFT/LV arm. In this multicenter trial, patients who underwent curative resection of liver metastases from colorectal cancer were randomly assigned to receive surgery alone or surgery followed by adjuvant chemotherapy with UFT/LV. The primary endpoint was relapse-free survival. Secondary endpoints included overall survival and safety. A total of 180 patients were enrolled, 90 were randomly assigned to receive UFT/LV therapy. Eighty two of whom were included in safety analyses. In the UFT/LV group, the completion rate of UFT/LV was 54.9%, the relative dose intensity was 70.8% and grade 3 or higher adverse events occurred in 12.2% of the patients. Elevated bilirubin levels, decreased hemoglobin levels, elevated alanine aminotransferase levels, diarrhea, anorexia were common. Most other adverse events were grade 2 or lower and tolerable. In conclusions, UFT/LV is a safe regimen for postoperative adjuvant chemotherapy in patients who have undergone resection of liver metastases from colorectal cancer. Further studies are warranted to improve completion rate, but UFT/LV is found to be a promising treatment in this setting.

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Scholarly attention to pharmaceutical companies' ability to sustain research and development (R&D) productivity has increased as they increasingly handle business challenges. Furthermore, the deterioration of R&D productivity has long been considered a major cause of mergers and acquisitions (M&As). This study attempts to investigate quantitatively the possible causes of the deterioration and the relationship between the deterioration and M&As by examining the Japanese pharmaceutical industry. Japan from 1980 to 1997 is an ideal case because of the availability of official data, but more importantly the significant changes in its business environment at the time. Using the Malmquist Index and data envelopment analysis, we measured the deterioration of R&D productivity from 1980 to 1997 based on a sample of 15 Japanese companies. Two lessons can be learned from Japan's case. First, to sustain R&D productivity over the long term, companies should use licensing activities and focus on the dominant therapeutic franchises. Second, if a company fails significantly to catch up with the benchmark, it is likely to pursue an M&A or seek an alternative way to improve R&D productivity. These findings appear similar to the current situation of the global pharmaceutical industry, although Japan pursued more licensing activities than M&A to improve R&D productivity.

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