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Showing papers by "Novartis published in 2001"


Journal ArticleDOI
TL;DR: STI571 is well tolerated and has significant antileukemic activity in patients with CML in whom treatment with interferon alfa had failed and demonstrates the potential for the development of anticancer drugs based on the specific molecular abnormality present in a human cancer.
Abstract: Background BCR-ABL is a constitutively activated tyrosine kinase that causes chronic myeloid leukemia (CML). Since tyrosine kinase activity is essential to the transforming function of BCR-ABL, an inhibitor of the kinase could be an effective treatment for CML. Methods We conducted a phase 1, dose-escalating trial of STI571 (formerly known as CGP 57148B), a specific inhibitor of the BCR-ABL tyrosine kinase. STI571 was administered orally to 83 patients with CML in the chronic phase in whom treatment with interferon alfa had failed. Patients were successively assigned to 1 of 14 doses ranging from 25 to 1000 mg per day. Results Adverse effects of STI571 were minimal; the most common were nausea, myalgias, edema, and diarrhea. A maximal tolerated dose was not identified. Complete hematologic responses were observed in 53 of 54 patients treated with daily doses of 300 mg or more and typically occurred in the first four weeks of therapy. Of the 54 patients treated with doses of 300 mg or more, cytogenetic res...

5,037 citations


Journal ArticleDOI
TL;DR: The BCR-ABL tyrosine kinase inhibitor STI571 is well tolerated and has substantial activity in the blast crises of CML and in Ph-positive ALL.
Abstract: Background BCR-ABL, a constitutively activated tyrosine kinase, is the product of the Philadelphia (Ph) chromosome. This enzyme is present in virtually all cases of chronic myeloid leukemia (CML) throughout the course of the disease, and in 20 percent of cases of acute lymphoblastic leukemia (ALL). On the basis of the substantial activity of the inhibitor in patients in the chronic phase, we evaluated STI571 (formerly known as CGP 57148B), a specific inhibitor of the BCR-ABL tyrosine kinase, in patients who had CML in blast crisis and in patients with Ph-chromosome–positive ALL. Methods In this dose-escalating pilot study, 58 patients were treated with STI571; 38 patients had myeloid blast crisis and 20 had ALL or lymphoid blast crisis. Treatment was given orally at daily doses ranging from 300 to 1000 mg. Results Responses occurred in 21 of 38 patients (55 percent) with a myeloid-blast-crisis phenotype; 4 of these 21 patients had a complete hematologic response. Of 20 patients with lymphoid blast crisis ...

2,724 citations


Journal ArticleDOI
TL;DR: Gastrointestinal stromal tumors are a group of mesenchymal neoplasms that arise from precursors of the connective-tissue cells of the gastrointestinal tract that occur predominantly in middle-aged and older persons.
Abstract: Gastrointestinal stromal tumors are a group of mesenchymal neoplasms that arise from precursors of the connective-tissue cells of the gastrointestinal tract.1 They occur predominantly in middle-aged and older persons, and approximately 70 percent of the tumors are found in the stomach, 20 to 30 percent are found in the small intestine, and less than 10 percent are found elsewhere in the gastrointestinal tract.1 Recent studies have shown that cells in gastrointestinal stromal tumors express a growth factor receptor with tyrosine kinase activity termed c-kit. This receptor, the product of the proto-oncogene c-kit, can be detected by immunohistochemical staining for . . .

2,000 citations


Journal ArticleDOI
TL;DR: Impatinib at a dose of 400 mg twice daily is well tolerated during the first 8 weeks, side-effects diminish with continuing treatment, and it has significant activity in patients with advanced GISTs.

1,269 citations


Journal ArticleDOI
TL;DR: An initiative between the European Federation of Pharmaceutical Industries Associations and the European Centre for the Validation of Alternative Methods to provide the researcher in the safety evaluation laboratory with an up‐to‐date, easy‐to-use set of data sheets to aid in the study design process.
Abstract: This article is the result of an initiative between the European Federation of Pharmaceutical Industries Associations (EFPIA) and the European Centre for the Validation of Alternative Methods (ECVAM). Its objectives are to provide the researcher in the safety evaluation laboratory with an up-to-date, easy-to-use set of data sheets to aid in the study design process whilst at the same time affording maximum welfare considerations to the experimental animals. Although this article is targeted at researchers in the European Pharmaceutical Industry, it is considered that the principles underpinning the data sets and refinement proposals are equally applicable to all those who use these techniques on animals in their research, whether in research institutes, universities or other sectors of industry. The implications of this article may lead to discussion with regulators, such as those responsible for pharmacopoeial testing. There are numerous publications dealing with the administration of test substances and the removal of blood samples, and many laboratories also have their own "in-house" guidelines that have been developed by custom and practice over many years. Within European Union Directive 86/609EEC1 we have an obligation to refine experiments to cause the minimum amount of stress. We hope that this article will provide background data useful to those responsible for protocol design and review. This guide is based on peer-reviewed publications whenever possible, but where this is not possible we have used "in-house" data and the experience of those on the working party (as well as helpful comments submitted by the industry) for a final opinion. The guide also addresses the continuing need to refine the techniques associated with the administration of substances and the withdrawal of blood, and suggests ways of doing so. Data-sharing between laboratories should be encouraged to avoid duplication of animal work, as well as sharing practical skills concerning animal welfare and scientific problems caused by "overdosing" in some way or another. The recommendations in this guide refer to the "normal" animal, and special consideration is needed, for instance, during pregnancy and lactation. Interpretation of studies may be confounded when large volumes are administered or excessive sampling employed, particularly if anaesthetics are used.

1,238 citations


Journal ArticleDOI
TL;DR: Targeting of the statin-binding site of LFA-1 could be used to treat diseases such as psoriasis, rheumatoid arthritis, ischemia/reperfusion injury and transplant rejection.
Abstract: The beta2 integrin leukocyte function antigen-1 (LFA-1) has an important role in the pathophysiology of inflammatory and autoimmune diseases. Here we report that statin compounds commonly used for the treatment of hypercholesterolemia selectively blocked LFA-1-mediated adhesion and costimulation of lymphocytes. This effect was unrelated to the statins' inhibition of 3-hydroxy-3-methylglutaryl coenzyme-A reductase; instead it occurred via binding to a novel allosteric site within LFA-1. Subsequent optimization of the statins for LFA-1 binding resulted in potent, selective and orally active LFA-1 inhibitors that suppress the inflammatory response in a murine model of peritonitis. Targeting of the statin-binding site of LFA-1 could be used to treat diseases such as psoriasis, rheumatoid arthritis, ischemia/reperfusion injury and transplant rejection.

1,041 citations


Journal ArticleDOI
TL;DR: Letrozole was significantly superior to tamoxifen in TTP, TTF, ORR, and clinical benefit rate, and its results support its use as first-line endocrine therapy in postmenopausal women with advanced breast cancer.
Abstract: PURPOSE: To compare the efficacy and tolerability of tamoxifen with that of letrozole, an oral aromatase inhibitor, with tamoxifen as first-line therapy in postmenopausal women with advanced breast cancer. PATIENTS AND METHODS: Nine hundred seven patients were randomly assigned letrozole 2.5 mg once daily (453 patients) or tamoxifen 20 mg once daily (454 patients). Patients had estrogen receptor– and/or progesterone receptor–positive tumors, or both receptors were unknown. Recurrence during adjuvant antiestrogen therapy or within the following 12 months or prior endocrine therapy for advanced disease precluded enrollment. One prior chemotherapy regimen for metastatic disease was allowed. The primary end point was time to progression (TTP). Secondary end points included overall objective response rate (ORR), its duration, rate and duration of clinical benefit, time to treatment failure (TTF), overall survival, and tolerability. RESULTS: TTP was significantly longer for letrozole than for tamoxifen (median,...

997 citations


Journal Article
TL;DR: Zoledronic acid (4 mg) via 15-minute intravenous infusion was as effective and well tolerated as 90 mg of pamidronate in the treatment of osteolytic and mixed bone metastases/lesions in patients with advanced breast cancer or multiple myeloma.
Abstract: PURPOSE Zoledronic acid, a new and more potent bisphosphonate, was compared with pamidronate, the current standard treatment for patients with osteolytic or mixed bone metastases/lesions. PATIENTS AND METHODS A total of 1,648 patients with either Durie-Salmon stage III multiple myeloma or advanced breast cancer and at least one bone lesion were randomly assigned to treatment with either 4 or 8 mg of zoledronic acid via 15-minute intravenous infusion or 90 mg of pamidronate via 2-hour intravenous infusion every 3 to 4 weeks for 12 months. The primary efficacy endpoint was the proportion of patients experiencing at least one skeletal-related event over 13 months. RESULTS The proportion of patients with at least one skeletal-related event was similar in all treatment groups. Median time to the first skeletal-related eventwas approximately 1 year in each treatment group. The skeletal morbidity rate was slightly lower in patients treated with zoledronic acid than in those treated with pamidronate, and zoledronic acid (4 mg) significantly decreased the incidence and event rate for radiation therapy to bone, both overall and in breast cancer patients receiving hormonal therapy. Pain scores decreased in all treatment groups in the presence of stable or decreased analgesic use. Zoledronic acid (4 mg) and pamidronate were equally well tolerated; the most common adverse events were bone pain, nausea, fatigue, and fever and < 5% of serious adverse events were related to the study drug. The incidence of renal impairment among patients treated with 4 mg of zoledronic acid via 15-minute infusion was similar to that among patients treated with pamidronate. CONCLUSIONS Zoledronic acid (4 mg) via 15-minute intravenous infusion was as effective and well tolerated as 90 mg of pamidronate in the treatment of osteolytic and mixed bone metastases/lesions in patients with advanced breast cancer or multiple myeloma. (Can-

891 citations


Journal ArticleDOI
TL;DR: It is concluded that the meal-related glucagon-like peptide-1 response in type 1 diabetes is decreased, which may contribute to the decreased incretin effect in type 2 diabetes.
Abstract: To elucidate the causes of the diminished incretin effect in type 2 diabetes mellitus we investigated the secretion of the incretin hormones, glucagon-like peptide-1 and glucose- dependent insulinotropic polypeptide and measured nonesterified fatty acids, and plasma concentrations of insulin, C peptide, pancreatic polypeptide, and glucose during a 4-h mixed meal test in 54 heterogeneous type 2 diabetic patients, 33 matched control subjects with normal glucose tolerance, and 15 unmatched subjects with impaired glucose tolerance. The glucagon-like peptide-1 response in terms of area under the curve from 0-240 min after the start of the meal was significantly decreased in the patients (2482 +/- 145 compared with 3101 +/- 198 pmol/liter.240 min; P = 0.024). In addition, the area under the curve for glucose-dependent insulinotropic polypeptide was slightly decreased. In a multiple regression analysis, a model with diabetes, body mass index, male sex, insulin area under the curve (negative influence), glucose-dependent insulinotropic polypeptide area under the curve (negative influence), and glucagon area under the curve (positive influence) explained 42% of the variability of the glucagon-like peptide-1 response. The impaired glucose tolerance subjects were hyperinsulinemic and generally showed the same abnormalities as the diabetic patients, but to a lesser degree. We conclude that the meal-related glucagon-like peptide-1 response in type 2 diabetes is decreased, which may contribute to the decreased incretin effect in type 2 diabetes.

853 citations


Journal ArticleDOI
Jun Kawai, Akira Shinagawa, K. Shibata, Masayasu Yoshino, Masayoshi Itoh, Y. Ishii, Takahiro Arakawa, A. Hara, Yoshifumi Fukunishi, Hideaki Konno, Jun Adachi, S. Fukuda, Katsunori Aizawa, Masaki Izawa, Kenichiro Nishi, H. Kiyosawa, S. Kondo, Itaru Yamanaka, Takashi Saito, Yasushi Okazaki, Takashi Gojobori1, Hidemasa Bono, Takeya Kasukawa2, Rintaro Saito, Koji Kadota, Hideo Matsuda3, Michael Ashburner, Serge Batalov4, Thomas L. Casavant5, W. Fleischmann, Terry Gaasterland6, Carmela Gissi7, Benjamin L. King, Hiromi Kochiwa8, P. Kuehl9, Simon L. Lewis10, Y. Matsuo, Itoshi Nikaido11, Graziano Pesole7, John Quackenbush12, Lynn M. Schriml13, F. Staubli, R. Suzuki8, Masaru Tomita8, Lukas Wagner13, Takanori Washio8, K. Sakai, Toshihisa Okido, Masaaki Furuno, H. Aono, Richard M. Baldarelli, Gregory S. Barsh14, Judith A. Blake, Dario Boffelli15, N. Bojunga, Piero Carninci, M. F. De Bonaldo5, Michael J. Brownstein13, Carol J. Bult, Christopher D.M. Fletcher4, Masaki Fujita16, Manuela Gariboldi, Stefano Gustincich17, David E. Hill, Marion A. Hofmann, David A. Hume18, Mamoru Kamiya, Norman H. Lee12, Paul A. Lyons19, Luigi Marchionni20, Jun Mashima1, J. Mazzarelli21, Peter Mombaerts6, P. Nordone22, Brian Z. Ring14, M. Ringwald, Ivan Rodriguez6, Naoaki Sakamoto, H. Sasaki23, K. Sato24, Christian Schönbach, Tsukasa Seya, Y. Shibata, Kai-Florian Storch, Harukazu Suzuki, Kazuhito Toyo-oka25, Kuan Hong Wang26, Charles J. Weitz17, Charles A. Whittaker26, L. Wilming27, Anthony Wynshaw-Boris25, K. Yoshida, Y. Hasegawa2, Hideya Kawaji2, Hideya Kawaji3, S. Kohtsuki2, Yoshihide Hayashizaki24 
08 Feb 2001-Nature
TL;DR: The first RIKEN clone collection is described, which is one of the largest described for any organism and analysis of these cDNAs extends known gene families and identifies new ones.
Abstract: The RIKEN Mouse Gene Encyclopaedia Project, a systematic approach to determining the full coding potential of the mouse genome, involves collection and sequencing of full-length complementary DNAs and physical mapping of the corresponding genes to the mouse genome. We organized an international functional annotation meeting (FANTOM) to annotate the first 21,076 cDNAs to be analysed in this project. Here we describe the first RIKEN clone collection, which is one of the largest described for any organism. Analysis of these cDNAs extends known gene families and identifies new ones.

700 citations


Journal ArticleDOI
TL;DR: This study shows that letrozole is more effective than tamoxifen as preoperative therapy in postmenopausal patients with ER and/or PgR positive primary untreated breast cancer and is at least as well tolerated.


Journal ArticleDOI
19 Jul 2001-Neuron
TL;DR: It is demonstrated that Balb/c mice lacking the GABA(B(1)) subunit are viable, exhibit spontaneous seizures, hyperalgesia, hyperlocomotor activity, and memory impairment, and casts doubt on the existence of proposed receptor subtypes.

Journal ArticleDOI
TL;DR: Three different in vitro methods, specifically, classic diffusion cell studies, attenuated total-reflectance-Fourier transform infrared spectroscopy, and tape stripping in conjunction with an appropriate analytical technique, are considered, emphasizing their application to obtain quantitative values for skin transport parameters and to separate the kinetic or thermodynamic effects of an enhancement strategy.

Journal ArticleDOI
TL;DR: It is demonstrated that inflamed peripheral tissues project their local chemokine profile to HEVs in draining LNs and thereby exert “remote control” over the composition of leukocyte populations that home to these organs from the blood.
Abstract: Interstitial fluid is constantly drained into lymph nodes (LNs) via afferent lymph vessels. This conduit enables monocyte-derived macrophages and dendritic cells to access LNs from peripheral tissues. We show that during inflammation in the skin, a second recruitment pathway is evoked that recruits large numbers of blood-borne monocytes to LNs via high endothelial venules (HEVs). Inhibition of monocyte chemoattractant protein (MCP)-1 blocked this inflammation-induced monocyte homing to LNs. MCP-1 mRNA in inflamed skin was over 100-fold upregulated and paralleled MCP-1 protein levels, whereas in draining LNs MCP-1 mRNA induction was much weaker and occurred only after a pronounced rise in MCP-1 protein. Thus, MCP-1 in draining LNs was primarily derived from inflamed skin. In MCP-1−/− mice, intracutaneously injected MCP-1 accumulated rapidly in the draining LNs where it enhanced monocyte recruitment. Intravital microscopy showed that skin-derived MCP-1 was transported via the lymph to the luminal surface of HEVs where it triggered integrin-dependent arrest of rolling monocytes. These findings demonstrate that inflamed peripheral tissues project their local chemokine profile to HEVs in draining LNs and thereby exert “remote control” over the composition of leukocyte populations that home to these organs from the blood.

Journal ArticleDOI
Eric Francotte1
TL;DR: The possible contribution of enantioselective chromatography with respect to the preparation ofEnantiomerically pure compounds is reviewed in the context of the competitive approaches and depending on the application scale, with a special emphasis on the recent progresses achieved in this particular field of separation.

Journal ArticleDOI
01 Apr 2001-Cancer
TL;DR: This study evaluated the dose–response relation for zoledronic acid, a new generation high potency bisphosphonate, given as a 5‐minute infusion in patients with malignant osteolytic disease.
Abstract: BACKGROUND This study evaluated the dose–response relation for zoledronic acid, a new generation high potency bisphosphonate, given as a 5-minute infusion in patients with malignant osteolytic disease. METHODS Two-hundred eighty patients with osteolytic lesions due to metastatic breast carcinoma or multiple myeloma were randomized to double-blind treatment with either 0.4, 2.0, or 4.0 mg of zoledronic acid or 90 mg pamidronate. The primary efficacy endpoint was the proportion of patients receiving radiation to bone. Other skeletal-related events, bone mineral density (BMD), bone markers, Eastern Cooperative Oncology Group performance status, pain and analgesic scores, and safety also were evaluated. RESULTS Zoledronic acid at doses of 2.0 and 4.0 mg and pamidronate at a dose of 90 mg each significantly reduced the need for radiation therapy to bone (P < 0.05) in contrast with 0.4 mg zoledronic acid, which did not. Skeletal-related events of any kind, pathologic fractures, and hypercalcemia also occurred less frequently in patients treated with 2.0 or 4.0 mg zoledronic acid or pamidronate than with 0.4 mg zoledronic acid. Increases in lumbar spine BMD (6.2–9.6%) and decreases in the bone resorption marker N-telopeptide (range, −37.1 to −60.8%) were observed for all treatment groups. Skeletal pain, fatigue, nausea, vomiting, and headache were the most commonly reported adverse events. Adverse events were similar in nature and frequency with zoledronic acid and pamidronate. CONCLUSIONS A 5-minute infusion of 2.0–4.0 mg zoledronic acid was at least as effective as a 2-hour 90-mg pamidronate infusion in treatment of osteolytic metastases. A 0.4-mg dose of zoledronic acid was significantly less effective. Both zoledronic acid and pamidronate were well tolerated. Cancer 2001;91:1191–200. © 2001 American Cancer Society.

Journal ArticleDOI
TL;DR: The observations thatSkp2 can mediate transformation and is up-regulated during oral epithelial carcinogenesis support a role for Skp2 as a protooncogene in human tumors.
Abstract: Skp2 is a member of the F-box family of substrate-recognition subunits of SCF ubiquitin–protein ligase complexes that has been implicated in the ubiquitin-mediated degradation of several key regulators of mammalian G1 progression, including the cyclin-dependent kinase inhibitor p27, a dosage-dependent tumor suppressor protein. In this study, we examined Skp2 and p27 protein expression by immunohistochemistry in normal oral epithelium and in different stages of malignant oral cancer progression, including dysplasia and oral squamous cell carcinoma. We found that increased levels of Skp2 protein are associated with reduced p27 in a subset of oral epithelial dysplasias and carcinomas compared with normal epithelial controls. Tumors with high Skp2 (>20% positive cells) expression invariably showed reduced or absent p27 and tumors with high p27 (>20% positive cells) expression rarely showed Skp2 positivity. Increased Skp2 protein levels were not always correlated with increased cell proliferation (assayed by Ki-67 staining), suggesting that alterations of Skp2 may contribute to the malignant phenotype without affecting proliferation. Skp2 protein overexpression may lead to accelerated p27 proteolysis and contribute to malignant progression from dysplasia to oral epithelial carcinoma. Moreover, we also demonstrate that Skp2 has oncogenic potential by showing that Skp2 cooperates with H-RasG12V to malignantly transform primary rodent fibroblasts as scored by colony formation in soft agar and tumor formation in nude mice. The observations that Skp2 can mediate transformation and is up-regulated during oral epithelial carcinogenesis support a role for Skp2 as a protooncogene in human tumors.

Journal ArticleDOI
TL;DR: Currently available reconstituted skin models cannot be regarded as generally useful for in-vitro penetration studies, and pig skin appeared as the most suitable model for human skin.

Journal ArticleDOI
TL;DR: To investigate the efficacy and safety of tegaserod, a novel 5‐HT4 receptor partial agonist, in a randomized, double‐blind, placebo‐controlled, 12‐week treatment, multicentre study.
Abstract: Aim: To investigate the efficacy and safety of tegaserod, a novel 5-HT4 receptor partial agonist, in a randomized, double-blind, placebo-controlled, 12-week treatment, multicentre study. Methods: Eight hundred and eighty-one patients with irritable bowel syndrome, characterized by abdominal pain, bloating and constipation, received tegaserod, 2 mg b.d. or 6 mg b.d., or placebo for 12 weeks. Results: Tegaserod, 2 mg b.d. and 6 mg b.d., showed a statistically significant relief of overall irritable bowel syndrome symptoms, measured by a weekly, self-administered questionnaire. At end-point, treatment differences from placebo were 12.7% and 11.8% for 2 mg b.d. and 6 mg b.d., respectively. The effect of tegaserod was noted as early as week 1, and was sustained over the 12-week treatment period. Individual irritable bowel syndrome symptoms assessed daily also showed a statistically significant improvement of abdominal discomfort/pain, number of bowel movements and stool consistency, and a favourable trend for reducing days with significant bloating. Adverse events were similar in all groups, with transient diarrhoea being the only adverse event seen more frequently with tegaserod than placebo. Conclusions: Based upon the results of this study, tegaserod offers rapid and sustained relief of the abdominal pain and constipation associated with irritable bowel syndrome. Tegaserod is also well tolerated.

Journal ArticleDOI
TL;DR: Resistance inducing chemicals that are able to induce broad disease resistance offer an additional option for the farmer to complement genetic disease resistance and the use of fungicides, if integrated properly in plant health management programs.
Abstract: Plants can be induced locally and systemically to become more resistant to diseases through various biotic or abiotic stresses. The biological inducers include necrotizing pathogens, non- pathogens or root colonizing bacteria. Through at network of signal pathways they induce resistance spectra and marker proteins that are characteristic for the different plant species and activation systems. The best characterized signal pathway for systemically induced resistance is SAR (systemic acquired resistance) that is activated by localized infections with necrotizing pathogens. It is characterized by protection against a broad range of pathogens, by a set of induced proteins and by its dependence on salicylic acid (SA) Various chemicals have been discovered that seem to act at various points in these defense activating networks and mimic all or parts of the biological activation of resistance. Of these, only few have reached commercialization. The best- studied resistance activator is acibenzolar-5-methyl (BION). At low rates it activates resistance in many crops against a broad spectrum of diseases, including fungi, bacteria and viruses. In monocots, activated resistance by BION typically is very long lasting, while the lasting effect is less pronounced in dicots. BION is translocated systemically in plants and can take the place of SA in the natural SAR signal pathway, inducing the same spectrum of resistance and the same set of molecular markers. Probenazole (ORYZEMATE) is used mainly on rice against rice blast and bacterial leaf blight. Its mode of action is not well understood partly because biological systems of systemically induced resistance are not well defined in rice. Treated plants clearly respond faster and in a resistant manner to infections by the two pathogens. Other compounds like beta-aminobutyric acid as wdl as extracts from plants and microorganisms have also been described as resistance inducers. For most of these, neither the mode of action nor reliable pre-challenge markers are known and still other pathways for resistance activation are suspected. Resistance inducing chemicals that are able to induce broad disease resistance offer an additional option for the farmer to complement genetic disease resistance and the use of fungicides. If integrated properly in plant health management programs, they can prolong the useful life of both the resistance genes and the fungicides presently used.

Journal ArticleDOI
TL;DR: Alkane/water partition coefficients can be derived from intrinsic membrane permeabilities, making this assay the first high-throughput method able to measure alkane/ water log P in the microtiterplate format.
Abstract: This study reports on a novel, high-throughput assay, designed to predict passive, transcellular permeability in early drug discovery. The assay is carried out in 96-well microtiterplates and measures the ability of compounds to diffuse from a donor to an acceptor compartment which are separated by a 9-10 microm hexadecane liquid layer. A set of 32 well-characterized, chemically diverse drugs was used to validate the method. The permeability values derived from the flux factors between donor and acceptor compartments show a good correlation with gastrointestinal absorption in humans. For comparison, correlations based on experimental or calculated octanol/water distribution coefficients (log D(o/w,6.8)) were significantly lower. In addition, this simple and robust assay allows determination of pH permeability profiles, critical information to predict gastrointestinal absorption of ionizable drugs and difficult to obtain from cell culture experiments. Correction for the unstirred water layer effect allows to differentiate between effective and intrinsic membrane permeability and opens up the dynamic range of the method. In addition, alkane/water partition coefficients can be derived from intrinsic membrane permeabilities, making this assay the first high-throughput method able to measure alkane/water log P in the microtiterplate format.

Journal ArticleDOI
TL;DR: Omalizumab has been reported to be safe and effective in improving asthma control and reducing the requirement for oral and inhaled corticosteroids, and cause a down-regulation of FcepsilonRI receptors on basophils.
Abstract: Background and Objective. There seems to be a strong causal relationship between allergy and the origins of asthma. Susceptibility to both is determined by a combination of genetics and environment acting through a complex network of cytokines. Nearly 90% of affected children have positive skin tests indicating the presence of specific immunoglobulin E (IgE), with sensitivity to house dust mite, Alternaria, cockroach, cat, and dog most closely linked to the disease. Greater exposure to house dust mite during infancy leads to earlier onset of wheezing, and elevated serum IgE levels correlate with the appearance of asthma symptoms. Specific IgE binds to high-affinity (FceRI) receptors on mast cells and basophils. The IgE-mediated reactions that follow exposure of sensitized mast cells to an allergen are designated early- and late-phase asthmatic responses (EAR and LAR). EAR is characterized by release of histamine and other preformed mediators within 1 hour of allergen exposure. It is often followed by LAR, an infiltration of the airways by inflammatory cells associated with an episode of more prolonged, and usually more severe airflow obstruction, 4 to 8 hours after antigen exposure. Chronic airway symptoms result from persistent LAR caused by continuous allergen exposure. IgE antibodies are capable of passive transfer of both EAR and LAR sensitivity. IgE-mediated mast cell activation contributes to chronic tissue eosinophilia and airway remodeling, with permanent loss in pulmonary function. Omalizumab (rhuMAb-E25) is a recombinant, humanized, monoclonal anti-IgE antibody of mouse origin developed for the treatment of IgE-mediated diseases. Omalizumab binds to free IgE at the same site as the high-affinity receptor. Although it attaches to free IgE, it does not bind to IgA, IgG, or cell-bound IgE. It therefore does not induce cross-linking of cell-bound IgE, which would lead to the release of allergic mediators. It has been reported to decrease serum IgE levels in a dose-dependent manner, inhibit EAR and LAR, and cause a down-regulation of FceRI receptors on basophils. Omalizumab has been reported to be safe and effective in improving asthma control and reducing the requirement for oral and inhaled corticosteroids. This double-blind, randomized, placebo-controlled study evaluated the safety, steroid-sparing effects, and impact on disease exacerbations of omalizumab in the treatment of childhood asthma. Methods. Participants were 334 males and premenarchal females aged 6 to 12 years, with moderate to severe allergic asthma requiring treatment with inhaled corticosteroids. During a run-in phase, all children were switched to equivalent doses of beclomethasone dipropionate (BDP), and the dose was adjusted to assure maintenance of asthma control achieved with previous corticosteroid treatment. Children were randomized to subcutaneously administered placebo (N = 109) or omalizumab (N = 225) at a dose based on body weight and initial serum IgE (0.016 mg/kg/IgE [IU/mL] per 4 weeks). BDP dose (initial range 168–420 μg/d) was kept stable for 16 weeks (stable-steroid phase), reduced over 8 weeks to the minimum effective dose (steroid-reduction phase), and maintained constant for the final 4 weeks. Results. More participants in the omalizumab group decreased their BDP dose, and their reduction was greater than that of the placebo group (median reduction 100% vs 66.7%). BDP was withdrawn completely in 55% of the omalizumab group versus 39% of the placebo group. The incidence and the frequency of asthma exacerbations requiring treatment with doubling of BDP dose or systemic corticosteroids were lower in the omalizumab group. The treatment differences were statistically significant during the steroid-reduction phase, during which fewer participants in the omalizumab group had asthma exacerbation episodes (18.2% vs 38.5%), and the mean number of episodes per patient was smaller than with placebo (0.42 vs 2.72). Five asthma exacerbations requiring hospitalization all occurred in the placebo group. Participants9 and investigators9 global evaluations of treatment effectiveness were more favorable for omalizumab than placebo. Investigators rated effectiveness excellent for 31.5% of the omalizumab group versus 16.3% of the placebo group and good for 44.7% of the omalizumab group versus 32.7% of the placebo group. There was little change in asthma symptom scores or spirometry measurements during either the stable-steroid or steroid dose-reduction phase, with minimal differences between the treatment groups. The requirement for rescue medication in the omalizumab group during both the stable-steroid and steroid dose-reduction phases was consistently lower than at baseline. At week 28, the median number of puffs of rescue medication taken daily was 0 in the omalizumab group and 0.46 in the placebo group. The change from baseline was significant in favor of omalizumab. Over the entire treatment period, patients in the omalizumab group missed a mean of 0.65 school days, compared with a mean of 1.21 days in the placebo group. The mean number of unscheduled medical contacts attributable to asthma-related medical problems was significantly smaller in the omalizumab group than in the placebo group throughout the treatment period (0.15 vs 5.35). Median reduction in serum free IgE was 95% to 99% among omalizumab patients. Median free IgE ranged from 133 to 790 IU/mL at baseline and was in the range of 6 to 9 IU/mL during the treatment period. The dosing scheme used in the trial therefore effectively reduced serum IgE in patients with initial concentrations as high as 1300 IU/mL. There was no reduction in free IgE in the placebo group. Omalizumab treatment was well tolerated. There were no serious treatment-related adverse events. The frequency and types of all adverse events were similar in the omalizumab and placebo groups. The majority of adverse events were mild to moderate in severity. No adverse events suggestive of serum sickness or immune complex formation were observed. Study-drug–related adverse events occurred more frequently in the omalizumab group than in the placebo group (6.2% vs 0.9%). Urticaria was reported in 9 omalizumab patients (4%) compared with 1 (0.9%) placebo patient and was mild or moderate in nearly all cases. Conclusion. Treatment with omalizumab is safe in children with asthma. It reduces the requirement for inhaled corticosteroids while protecting against disease exacerbation.

Journal ArticleDOI
TL;DR: The RNAi response can be induced effectively by long dsRNA in nondifferentiated mouse cells grown in culture, and siRNAs recently have been shown to act as potent inducers of RNAi in cultured mammalian cells.
Abstract: In eukaryotes, double-stranded (ds) RNA induces sequence-specific inhibition of gene expression, referred to as RNA interference (RNAi). In invertebrates, RNAi can be triggered effectively by either long dsRNAs or 21- to 23-nt-long short interfering (si) duplex RNAs, acting as effectors of RNAi. siRNAs recently have been shown to act as potent inducers of RNAi in cultured mammalian cells. However, studies of RNAi activated by long dsRNA are impeded by its nonspecific effects, mediated by dsRNA-dependent protein kinase PKR and RNase L. Here, we report that the RNAi response can be induced effectively by long dsRNA in nondifferentiated mouse cells grown in culture. Transfection of dsRNA into embryonal carcinoma (EC) P19 and F9 cells results in a sequence-specific decrease in the level of proteins expressed from either exogenous or endogenous genes. dsRNA-mediated inhibition of the reporter gene also occurs in mouse embryonic stem cells. The RNAi effect is mediated by siRNAs, which are generated by cleavage of dsRNA by the RNaseIII-like enzyme, Dicer. We demonstrate that extracts prepared from EC cells catalyze processing of dsRNA into ≈23-nt fragments and that Dicer localizes to the cytoplasm of EC and HeLa cells.

Journal ArticleDOI
Lindsey Hudson1, Stuart Bevan1, Glen Wotherspoon1, Clive Gentry1, Alyson Fox1, Janet Winter1 
TL;DR: Examination of the expression of the sensory neuron‐specific cation channel Vanilloid Receptor 1 (VR1), an important transducer of noxious stimuli, in three models of nerve injury in the rat found that VR1‐IR persisted in the transected sciatic nerve proximal to the lesion, despite its down‐regulation in the damaged neuronal somata.
Abstract: Changes in phenotype or connectivity of primary afferent neurons following peripheral nerve injury may contribute to the hyperalgesia and allodynia associated with neuropathic pain conditions. Although earlier studies using partial nerve injury models have focused on the role of damaged fibres in the generation of ectopic discharges and pain, it is now thought that remaining undamaged fibres may be equally important. We have examined the expression of the sensory neuron-specific cation channel Vanilloid Receptor 1 (VR1), an important transducer of noxious stimuli, in three models of nerve injury in the rat, using anatomical separation or fluorescent retrograde tracers to identify damaged or undamaged sensory neurons. After total or partial sciatic nerve transection, or spinal nerve ligation, VR1-immunoreactivity (IR) was significantly reduced in the somata of all damaged dorsal root ganglion (DRG) neuronal profiles, compared to controls. However, after partial transection or spinal nerve ligation, VR1 expression was greater in the undamaged DRG somata than in controls. Unexpectedly, after L5 spinal nerve ligation, VR1-IR of the A-fibre somata increased approximately 3-fold in the uninjured L4 DRG compared to controls; a much greater increase than seen in the somata with C-fibres. Furthermore, we found that VR1-IR persisted in the transected sciatic nerve proximal to the lesion, despite its down-regulation in the damaged neuronal somata. This persistence in the nerve proximal to the lesion after nerve section, together with increased VR1 in DRG neurons left undamaged after partial nerve injury, may be crucial to the development or maintenance of neuropathic pain.

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TL;DR: The data indicate that multiple allosteric interactions between the two subunits are required for wild‐type functioning of the GABAB receptor and highlight further the importance of the dimerization process in GPCR activation.
Abstract: Recent studies on G-protein-coupled receptors revealed that they can dimerize. However, the role of each subunit in the activation process remains unclear. The gamma-amino-n-butyric acid type B (GABA(B)) receptor is comprised of two subunits: GB1 and GB2. Both consist of an extracellular domain (ECD) and a heptahelical domain composed of seven transmembrane alpha-helices, loops and the C-terminus (HD). Whereas GB1 ECD plays a critical role in ligand binding, GB2 is required not only to target GB1 subunit to the cell surface but also for receptor activation. Here, by analysing chimeric GB subunits, we show that only GB2 HD contains the determinants required for G-protein signalling. However, the HD of GB1 improves coupling efficacy. Conversely, although GB1 ECD is sufficient to bind GABA(B) ligands, the ECD of GB2 increases the agonist affinity on GB1, and is necessary for agonist activation of the receptor. These data indicate that multiple allosteric interactions between the two subunits are required for wild-type functioning of the GABA(B) receptor and highlight further the importance of the dimerization process in GPCR activation.

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01 Aug 2001-Diabetes
TL;DR: Although the increased adiposity is paradoxical to an improvement in insulin sensitivity, the quantitative increase of adipose mass should be viewed in context of the qualitative changes in adipose tissue, including the remodeling of adipocytes to a smaller size with higher lipid storage potential.
Abstract: Obesity and dysfunctional energy partitioning can lead to the development of insulin resistance and type 2 diabetes. The antidiabetic thiazolidinediones shift the energy balance toward storage, leading to an increase in whole-body adiposity. These studies examine the effects of pioglitazone (Pio) on adipose tissue physiology, accumulation, and distribution in female Zucker (fa/fa) rats. Pio treatment (up to 28 days) decreased the insulin-resistant and hyperlipidemic states and increased food consumption and whole-body adiposity. Magnetic resonance imaging (MRI) analysis and weights of fat pads demonstrated that the increase in adiposity was not only limited to the major fat depots but also to fat deposition throughout the body. Adipocyte sizing profiles, fat pad histology, and DNA content show that Pio treatment increased the number of small adipocytes because of both the appearance of new adipocytes and the shrinkage and/or disappearance of existing mature adipocytes. The remodeling was time dependent, with new small adipocytes appearing in clusters throughout the fat pad, and accompanied by a three- to fourfold increase in citrate synthase and fatty acid synthase activity. The appearance of new fat cells and the increase in fat mass were depot specific, with a rank order of responsiveness of ovarian > retroperitoneal > subcutaneous. This differential depot effect resulted in a redistribution of the fat mass in the abdominal region such that there was an increase in the visceral:subcutaneous ratio, as confirmed by MRI analysis. Although the increased adiposity is paradoxical to an improvement in insulin sensitivity, the quantitative increase of adipose mass should be viewed in context of the qualitative changes in adipose tissue, including the remodeling of adipocytes to a smaller size with higher lipid storage potential. This shift in energy balance is likely to result in lower circulating free fatty acid levels, ultimately improving insulin sensitivity and the metabolic state.

Journal ArticleDOI
01 May 2001-Pain
TL;DR: The data show that cannabinoids are highly potent and efficacious antihyperalgesic agents in a model of neuropathic pain and mediated via an action in both the CNS and in the periphery.
Abstract: We have examined the effects of cannabinoid agonists on hyperalgesia in a model of neuropathic pain in the rat and investigated the possible sites of action. The antihyperalgesic activity of the cannabinoids was compared with their ability to elicit behavioural effects characteristic of central cannabinoid activity. WIN55,212-2 (0.3–10 mg kg−1), CP-55,940 (0.03–1 mg kg−1) and HU-210 (0.001–0.03 mg kg−1) were all active in a ‘tetrad’ of tests consisting of tail-flick, catalepsy, rotarod and hypothermia following subcutaneous administration, with a rank order of potency in each of HU-210>CP-55,940>WIN55,212-2. The effects of WIN55,212-2 in each assay were blocked by the Cannabinoid1 (CB1) antagonist SR141716A. In the partial sciatic ligation model of neuropathic pain WIN55,212-2, CP-55,940 and HU-210 produced complete reversal of mechanical hyperalgesia within 3 h of subcutaneous administration with D50 values of 0.52, 0.08 and 0.005 mg kg−1, respectively. In this model WIN55,212-2 was also effective against thermal hyperalgesia and mechanical allodynia. WIN55,212-2 produced pronounced reversal of mechanical hyperalgesia following intrathecal administration that was blocked by the CB1 antagonist SR141716A. Following intraplantar administration into the ipsilateral hindpaw, WIN55,212-2 produced up to 70% reversal of mechanical hyperalgesia, although activity was also observed at high doses following injection into the contralateral paw. The antihyperalgesic effect of WIN55,212-2 injected into the ipsilateral paw was blocked by subcutaneously administered SR141716A, but was not affected by intrathecally administered SR141716A. These data show that cannabinoids are highly potent and efficacious antihyperalgesic agents in a model of neuropathic pain. This activity is likely to be mediated via an action in both the CNS and in the periphery.

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TL;DR: Three successful examples of drug design at Novartis using a tyrosine kinase as a molecular target are described and promising data from phase I and II clinical trials in CML patients support the fact that the STI571 represents a new treatment modality for CML.
Abstract: Protein kinases play a crucial role in signal transduction as well as in cellular proliferation, differentiation, and various regulatory mechanisms. The inhibition of growth related kinases, especially tyrosine kinases, might provide new therapies for diseases such as cancer. The progress made in the crystallization of protein kinases has confirmed that the ATP-binding domain of tyrosine kinases is an attractive target for drug design. Three successful examples of drug design at Novartis using a tyrosine kinase as a molecular target are described. PKI166, a pyrrolo[2,3,-d]pyrimidine derivative, is a dual inhibitor of both the EGFR and the ErbB2 kinases. The compound entered clinical trials in 1999, based on its favorable preclinical profile: potent inhibition of EGF-mediated signalling in cells, in vivo antitumor activity in several EGFR overexpressing xenograft tumor models in nude mice, long-lasting inhibition of EGF-stimulated EGFR autophosphorylation in tumor tissue, good oral bioavailability in animals, and no prohibitive in vitro and in vivo toxicity findings. The anilino-phthalazine derivative PTK787/ZK222584 (Phase I, co-developed by Schering AG, Berlin) is a potent and selective inhibitor of both the KDR and Flt-1 kinases with interesting anti-angiogenic and pharmacokinetic properties (orally bioavailable). STI571 (Glivec, Gleevec), a phenylamino-pyrimidine derivative, is a potent inhibitor of the Abl tyrosine kinase, which is present in 95% of patients with chronic myelogenous leukemia (CML). The compound specifically inhibits proliferation of v-Abl and Bcr-Abl expressing cells (including cells from CML patients) and shows anti-tumor activity as a single agent in animal models at well-tolerated doses. Pharmacologically relevant concentrations are achieved in the plasma of animals (oral administration). Promising data from phase I and II clinical trials in CML patients (98% haematological response rate in Phase I) support the fact that the STI571 represents a new treatment modality for CML. In addition, potent inhibition of the PDGFR and c-Kit tyrosine kinases also indicates its possible clinical use in solid tumors.

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TL;DR: The data suggest that selective mGlu5 receptor antagonists may play a role in the therapy of anxiety and/or depression, further studies are required to identify the sites and the mechanism of action of MPEP.
Abstract: Several lines of evidence suggest a crucial involvement of glutamate in the mechanism of action of anxiolytic and/or antidepressant drugs. The involvement of group I mGlu receptors in anxiety and depression has also been proposed. Given the recent discovery of a selective and brain penetrable mGlu5 receptor antagonists, the effect of 2-methyl-6-(phenylethynyl)-pyridine (MPEP), i.e. the most potent compound described, was evaluated in established models of anxiety and depression. Experiments were performed on male Wistar rats or male Albino Swiss or C57BL/6J mice. The anxiolytic-like effects of MPEP was tested in the conflict drinking test and the elevated plus-maze test in rats as well as in the four-plate test in mice. The antidepressant-like effect was estimated using the tail suspension test in mice and the behavioural despair test in rats. MPEP (1 – 30 mg kg−1) induced anxiolytic-like effects in the conflict drinking test and the elevated plus-maze test in rats as well as in the four-plate test in mice. MPEP had no effect on locomotor activity or motor coordination. MPEP (1 – 20 mg kg−1) did shorten the immobility time in a tail suspension test in mice, however it was inactive in the behavioural despair test in rats. These data suggest that selective mGlu5 receptor antagonists may play a role in the therapy of anxiety and/or depression, further studies are required to identify the sites and the mechanism of action of MPEP. British Journal of Pharmacology (2001) 132, 1423–1430; doi:10.1038/sj.bjp.0703923