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111.
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Hiromi Sasaki Swathi V. Iyer Ken Sasaki Ossama W. Tawfik Tomoo Iwakuma 《Analytical biochemistry》2015
Osteosarcoma, the most common type of primary bone cancer, is the second highest cause of cancer-related death in pediatric patients. To understand the mechanisms behind osteosarcoma progression and to discover novel therapeutic strategies for this disease, a reliable and appropriate mouse model is essential. For this purpose, osteosarcoma cells need to be injected into the bone marrow. Previously, the intratibial and intrafemoral injection methods were reported; however, the major drawback of these methods is the potential leakage of tumor cells from the injection site during or after these procedures. To overcome this, we have established an improved method to minimize leakage in an orthotopic mouse model of osteosarcoma. By taking advantage of the anatomical benefits of the femur with less bowing and larger medullary cavity than those of the tibia, osteosarcoma cells are injected directly into the femoral cavity following reaming of its intramedullary space. To prevent potential leakage of tumor cells during and after the surgery, the injection site is sealed with bone wax. This method requires a minor surgery of approximately 15 min under anesthesia. Our established orthotopic osteosarcoma model could serve as a valuable and reliable tool for examining progression of various types of bone tumors. 相似文献
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Background
The ubiquitin system (Ub-system) can be defined as the ensemble of components including Ub/ubiquitin-like proteins, their conjugation and deconjugation apparatus, binding partners and the proteasomal system. While several studies have concentrated on structure-function relationships and evolution of individual components of the Ub-system, a study of the system as a whole is largely lacking. 相似文献116.
Matthew C. Lucas David S. Carter Hai-Ying Cai Eun Kyung Lee Ryan C. Schoenfeld Sandra Steiner Marzia Villa Robert J. Weikert Pravin S. Iyer 《Bioorganic & medicinal chemistry letters》2009,19(16):4630-4633
A variety of novel aminoheterocycle scaffolds as selective monoamine reuptake inhibitors have been prepared and one of these scaffolds is achiral. The main elements responsible for hERG channel, CYP2D6 and CYP3A4 inhibition were identified. 相似文献
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Thomas F. Boat Pi Wan Cheng Rama N. Iyer Don M. Carlson Ilona Polony 《Archives of biochemistry and biophysics》1976,177(1):95-104
Mucous glycoproteins were isolated by agarose gel filtration from nonpurulent tracheobronchial secretions and purulent sputum which had been reduced, carboxymethylated and, in the case of purulent secretions, treated with deoxyribonuclease. The solubilized and purified glycoproteins were fractionated on diethylaminoethyl cellulose into two major (I, II) and two minor (Ia, III) blood group active components. Components I and II had similar carbohydrate and amino acid compositions which were typical for human blood group substances. These two components did differ in several respects. Component I contained 1.4–2.6% sulfate and did not inhibit influenza virus hemagglutination while component II contained 7.1–7.8% sulfate and was a potent inhibitor of virus hemagglutination. Component II also migrated more rapidly on sodium dodecyl sulfate-3.3% acrylamide gel electrophoresis. Components I and II in purulent secretions displayed only minor compositional differences from their counterparts in nonpurulent secretions. Component II was more abundant in two sputum samples from subjects with cystic fibrosis than in purulent bronchitic secretions or in nonpurulent secretions. 相似文献
119.
Benjamin E. Blass Pravin Iyer Magid Abou-Gharbia Wayne E. Childers John C. Gordon Mercy Ramanjulu George Morton Premkumar Arumugam Joshodeep Boruwa John Ellingboe Sayan Mitra Rajashekar Reddy Nimmareddy Shalini Paliwal Jamallamudi Rajasekhar Savithiri Shivakumar Pratima Srivastava Raghuram S. Tangirala Konda Venkataramanaiah L. Krishnakanth Reddy 《Bioorganic & medicinal chemistry letters》2018,28(13):2270-2274
The synthesis of steroid hormones is critical to human physiology and improper regulation of either the synthesis of these key molecules or activation of the associated receptors can lead to disease states. This has led to intense interest in developing compounds capable of modulating the synthesis of steroid hormones. Compounds capable of inhibiting Cyp19 (Aromatase), a key enzyme in the synthesis of estrogens, have been successfully employed as breast cancer therapies, while inhibitors of Cyp17 (17α-hydroxylase-17,20-lyase), a key enzyme in the synthesis of glucocorticoids, mineralocorticoids and steroidal sex hormones, are a key component of prostate cancer therapy. Inhibition of CYP17 has also been suggested as a possible target for the treatment of Cushing Syndrome and Metabolic Syndrome. We have identified two novel series of stilbene based CYP17 inhibitors and demonstrated that exemplary compounds in these series have pharmacokinetic properties consistent with orally delivered drugs. These findings suggest that compounds in these classes may be useful for the treatment of diseases and conditions associated with improper regulation of glucocorticoids synthesis and glucocorticoids receptor activation. 相似文献
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Stable coexistence of Rfi factors in Escherichia coli 总被引:7,自引:0,他引:7