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PURPOSE: The epothilones are a novel class of nontaxane microtubule-stabilizing agents. BMS-247550 is a semisynthetic analog of the natural product epothilone B. We conducted a phase I study administering BMS-247550 as a 1-hour intravenous infusion daily for 5 consecutive days every 21 days. PATIENTS AND METHODS: Twenty-one patients received BMS-247550 without filgrastim in the first cycle. An additional six patients were enrolled at a starting dose of 8 mg/m2/d with filgrastim support. Twenty-one of the 27 patients had received prior paclitaxel, docetaxel, or both. RESULTS: One hundred seven cycles were administered to 27 patients. The maximum-tolerated dose was 6 mg/m2 of BMS-247550 administered as a 1-hour intravenous infusion daily for 5 consecutive days every 21 days. Dose-limiting toxicity at a dose of 8 mg/m2/d was neutropenia with or without filgrastim support. Nonhematologic grade 3 toxicities included fatigue (seven cycles), stomatitis (two cycles), and anorexia (one cycle). The mean terminal half-life of BMS-247550 was 16.8 +/- 6.0 hours, the volume of distribution at steady-state was 798 +/- 375 L, and the clearance was 712 +/- 247 mL/min. Objective responses were observed in patients with breast, cervical, and basal cell cancer. Reductions in CA-125 levels were noted in patients with ovarian cancer. CONCLUSION: The recommended phase II dose of BMS-247550 on the daily schedule for 5 days is 6 mg/m2/d. Neutropenia was dose limiting, but higher doses were tolerated by a large fraction of patients with filgrastim support. Peripheral neuropathy was mild, even after multiple cycles of therapy, and was not dose limiting.  相似文献   
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Hot-melt extrusion technology was used to produce thin films containing a model drug, lidocaine, and the cellulosic polymers hydroxypropyl cellulose (HPC) and hydroxypropyl methyl cellulose (HPMC). Two film formulations were extruded and compared, one containing only HPC and the other containing HPC:HPMC (80:20). Thermal analysis of the films using differential scanning calorimetry (DSC) suggested that the drug existed in the amorphous condition, which was confirmed by wide angle X-ray diffractometry. Sustained release of the drug was observed from both of the polymer matrices. Dissolution profiles suggested that HPMC retarded the drug release from HPC:HPMC (80:20) films. However, the mechanism of drug release from both of the films was predominantly diffusion of the drug through the polymer matrices. Incorporation of HPMC also increased both adhesive strength and work of adhesion as compared to the HPC-only films.  相似文献   
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Some new 1H-benzo[b]xanthene and 4H-benzo[g]chromene derivatives of N-allyl quinolone were efficiently synthesized via microwave-induced one-pot three component reaction of N-allyl quinolones, 2-hydroxy-1,4-naphthoquinone and cyclic β-diketones/malononitrile, and iso-propylcyanoacetate in the presence of catalytic amount of ceric ammonium nitrate under solvent-free condition. This methodology allowed us to achieve the desired products in excellent yields in a very short time without the use of solvent. The % atom economy was calculated for all the newly synthesized compounds and found in the range of 92–96 %. Titled derivatives were elucidated by 1H NMR, 13C NMR, FT-IR, elemental analysis, and mass spectral data as well as tested against a panel of pathogenic strains of bacteria and fungi using by microdilution minimum inhibitory concentration method. The structural activity relationship analysis demonstrated that electronic influence and lipophilicity of different groups make much difference in the antimicrobial potency.  相似文献   
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Skeletal metastasis as a primary presentation of gall bladder carcinoma is rare. A 50-year-old lady presented with neck pain and weakness in her right upper limb of 3 months duration. Clinical and imaging work-up suggested locally advanced gall bladder carcinoma with metastasis to cervical vertebra and sternum. Only one case till date has been reported where the patient presented with neurological symptoms due to pathological fracture secondary to metastasis from an occult gall bladder carcinoma. Although rare, an occult gall bladder cancer may present with neurological symptoms due to pathological fracture of spine secondary to metastasis. We present a brief review of literature of patients who presented with skeletal metastases in clinically silent gall bladder malignancy. Palliative care issues in advanced gall bladder carcinoma have also been discussed.  相似文献   
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Cardiac myosin binding protein C (cMyBP-C) is an integral sarcomeric protein that associates with the thick, thin, and titin filament systems in the contractile apparatus. Three different isoforms of MyBP-C exist in mammalian muscle: slow skeletal (MyBPC1), fast skeletal (MyBP-C2, with several variants), and cardiac (cMyBP-C). Genetic screening studies show that mutations in MYBPC3 occur frequently and are responsible for as many as 30–35 % of identified cases of familial hypertrophic cardiomyopathy. The function of cMyBP-C is stringently regulated by its post-translational modification. In particular, the addition of phosphate groups occurs with high frequency on certain serine residues that are located in the cardiac-specific regulatory M domain. Phosphorylation of this domain has been extensively studied in vitro and in vivo. Phosphorylation of the M domain can regulate the manner in which actin and myosin interact, affecting the cross bridge cycle and ultimately, cardiac hemodynamics.  相似文献   
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