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Tuttha Bhasma (TB) is an important metal based drug used in Ayurveda. It has widespread therapeutic uses in the treatment of metabolic disorders. Despite of its therapeutic utility there is a lack of data related to its safety. Hence the present study was undertaken to evaluate chronic toxicity of TB in Wistar albino rats. Chronic toxicity study was conducted as per AYUSH guidelines 170 and the parameters such as ponderal changes; biochemical, hematological and histopathological examinations were recorded. Based on the overall toxicity profile significant changes in the serum SGPT was noted in therapeutic and higher dose levels. We could see the serum cholesterol, SGOT, SGPT and albumin levels were significantly elevated at lower dose compared to the control group. Histopathology of kidney showed cell infiltration and sections from liver showed mild to moderate fatty changes at higher dose levels. Histopathology of jejunum revealed there was mild to moderate epithelial erosion and shortening of epithelial layer. However overall toxicity study parameters showed the test drug TB is well tolerated and no dose dependent toxicity symptoms were observed. Based on the findings we could conclude that Tuttha bhasma is much safer to use at therapeutic dose level. However, at higher dose levels there are chances of organ toxicity.

Several families of protein kinases have been shown to play a critical role in the regulation of cell cycle progression, particularly progression through mitosis. These kinase families include the Aurora kinases, the Mps1 gene product and the Polo Like family of protein kinases (PLKs). The PLK family consists of five members and of these, the role of PLK1 in human cancer is well documented. PLK2 (SNK), which is highly homologous to PLK1, has been shown to play a critical role in centriole duplication and is also believed to play a regulatory role in the survival pathway by physically stabilizing the TSC1/2 complex in tumor cells under hypoxic conditions. As a part of our research program, we have developed a library of novel ATP mimetic chemotypes that are cytotoxic against a panel of cancer cell lines. We show that one of these chemotypes, the 6-arylsulfonyl pyridopyrimidinones, induces apoptosis of human tumor cell lines in nanomolar concentrations. The most potent of these compounds, 7ao, was found to be a highly specific inhibitor of PLK2 when profiled against a panel of 288 wild type, 55 mutant and 12 lipid kinases. Here, we describe the synthesis, structure activity relationship, in vitro kinase specificity and biological activity of the lead compound, 7ao.

Fabricating nanofibrous scaffolds with robust blood compatibility remains an unmet challenge for cardiovascular applications since anti-thrombogenic surface coatings did not withstand physiological shear force. Hence, the present study envisages the influence of smooth and porous topographies of poly(lactic acid) (PLA) nanofibers on hemocompatibility as it could offer time-independent blood compatibility. Further, recent studies have evolved to integrate various contrasting agents for augmenting the prognostic properties of tissue engineered scaffolds; an attempt was also made to synthesize Curcumin–superparamagnetic iron oxide nanoparticle complex (Cur–SPION) as a contrasting agent and impregnated into PLA nanofibers for evaluating the blood compatibility. Herein, electrospun nanofibers of PLA with different topographies (smooth and porous) were fabricated and characterized for surface morphology, zeta potential, fluorescence, and crystallinity. The scaffolds with smooth, porous and rough surface topographies were thoroughly investigated for its hemocompatibility by evaluating hemolysis percentage, platelet adhesion, in vitro kinetic clotting time, serum protein adsorption, plasma recalcification time (PRT), capture and release of erythrocytes. Although the nanofibers of all three groups showed acceptable hemolytic percentage (HP

Monoclonal antibody production in glycoengineered Pichia pastoris was optimized for high cell density fed-batch fermentations. Results show that antibody productivity was 1.72-fold higher when maintaining oxygen-limited conditions compared to methanol-limited conditions during the protein production phase of the bioprocess. Under oxygen-limited conditions with a 30 mmol L −1 h −1 of oxygen uptake rate, an optimum methanol dosage level of 10 gL −1 was established by comparing antibody titers under different methanol dosages during protein production. Real-time on-line NIR monitoring of glycerol concentration, methanol concentration, and relative cell density provided valuable data for process characterization and optimization. Real-time profiles of glycerol concentration and relative cell density documented run-to-run consistency during the batch and fed-batch phases by analyses of the glycerol consumption and cell growth kinetics. The volumetric methanol consumption rate was characterized for the induction process following the end of the glycerol fed-batch phase. Under oxygen-limited conditions, the volumetric methanol consumption rate increased over a 60-h period and this increase was independent of the methanol concentration over a range of 2.5–30 gL −1 when the oxygen utilization rate was maintained at 30 mmol L −1 h −1 . Utility of the on-line NIR monitor is demonstrated over the one-year period of this investigation by accurately tracking biomass, glycerol concentration, and methanol concentration without user required recalibration as well as by documenting abnormal events during high cell density bioprocesses.

The success of imatinib, a BCR-ABL inhibitor for the treatment of chronic myelogenous leukemia, has created a great impetus for the development of additional kinase inhibitors as therapeutic agents. However, the complexity of cancer has led to recent interest in polypharmacological approaches for developing multikinase inhibitors with low toxicity profiles. With this goal in mind, we analyzed more than 150 novel cyano pyridopyrimidine compounds and identified structure–activity relationship trends that can be exploited in the design of potent kinase inhibitors. One compound, 8-cyclopentyl-2-[4-(4-methyl-piperazin-1-yl)-phenylamino]-7-oxo-7,8-dihydro-pyrido[2,3-d]pyrimidine-6-carbonitrile (7x), was found to be the most active, inducing apoptosis of tumor cells at a concentration of approximately 30–100 nM. In vitro kinase profiling revealed that 7x is a multikinase inhibitor with potent inhibitory activity against the CDK4/CYCLIN D1 and ARK5 kinases. Here, we report the synthesis, structure–activity relationship, kinase inhibitory profile, in vitro cytotoxicity, and in vivo tumor regression studies by this lead compound.

Pichia pastoris is a methylotropic yeast that has gained great importance as an organism for protein expression in recent years. Here, we report the expression of recombinant human erythropoietin (rhEPO) in glycoengineered P. pastoris. We show that glycosylation fidelity is maintained in fermentation volumes spanning six orders of magnitude and that the protein can be purified to high homogeneity. In order to increase the half-life of rhEPO, the purified protein was coupled to polyethylene glycol (PEG) and then compared to the currently marketed erythropoiesis stimulating agent, Aranesp(®) (darbepoetin). In in vitro cell proliferation assays the PEGylated protein was slightly, and the non-PEGylated protein was significantly more active than comparator. Pharmacodynamics as well as pharmacokinetic activity of PEGylated rhEPO in animals was comparable to that of Aranesp(®). Taken together, our results show that glycoengineered P. pastoris is a suitable production host for rhEPO, yielding an active biologic that is comparable to those produced in current mammalian host systems.

Cyclin D proteins are elevated in many cancer cells and targeted deletion of Cyclin D1 gene in the mammary tissues protects mice from breast cancer. Accordingly, there is an increasing awareness of this novel non-enzymatic target for cancer therapeutics. We have developed novel, non-alkylating styryl benzyl sulfones that induce cell death in wide variety of cancer cells without affecting the proliferation and survival of normal cells. The development of derivatized Styryl Benzyl Sulfones followed logically from a tumor cell cytotoxicity screen performed in our laboratory that did not have an a priori target profile. Modifications of some of the precursor molecules led to lead optimization with regard to tumor cell cytotoxicity. In this report we describe the synthesis and structure-activity relationships of novel, non-alkylating (E) styryl benzyl sulfones, and the development of the novel anti-cancer agent sodium (E)-2-{2-methoxy-5-[(2′,4′,6′-trimethoxystyrylsulfonyl)methyl]phenylamino}-acetate (ON 01910.Na), which is in Phase III trials for myelodysplastic syndromes (MDS) associated with aberrant expression of cyclin D proteins.

Mammalian cell culture systems are used predominantly for the production of therapeutic monoclonal antibody (mAb) products. A number of alternative platforms, such as Pichia engineered with a humanized N-linked glycosylation pathway, have recently been developed for the production of mAbs. The glycosylation profiles of mAbs produced in glycoengineered Pichia are similar to those of mAbs produced in mammalian systems. This report presents for the first time the comprehensive characterization of an anti-human epidermal growth factor receptor 2 (HER2) mAb produced in a glycoengineered Pichia, and a study comparing the anti-HER2 from Pichia, which had an amino acid sequence identical to trastuzumab, with trastuzumab. The comparative study covered a full spectrum of preclinical evaluation, including bioanalytical characterization, in vitro biological functions, in vivo anti-tumor efficacy and pharmacokinetics in both mice and non-human primates. Cell signaling and proliferation assays showed that anti-HER2 from Pichia had antagonist activities comparable to trastuzumab. However, Pichia-produced material showed a 5-fold increase in binding affinity to FcγIIIA and significantly enhanced antibody dependant cell-mediated cytotoxicity (ADCC) activity, presumably due to the lack of fucose on N-glycans. In a breast cancer xenograft mouse model, anti-HER2 was comparable to trastuzumab in tumor growth inhibition. Furthermore, comparable pharmacokinetic profiles were observed for anti-HER2 and trastuzumab in both mice and cynomolgus monkeys. We conclude that glycoengineered Pichia provides an alternative production platform for therapeutic mAbs and may be of particular interest for production of antibodies for which ADCC is part of the clinical mechanism of action.

Growth of the antibody market has fueled the development of alternative expression systems such as glycoengineered yeast. Although intact antibody expression levels in excess of 1 g L(-1) have been demonstrated in glycoengineered yeast, this is still significantly below the titers reported for antibody fragments in fungal expression systems. This study presents a simplified approach to estimate antibody secretion kinetics and oxygen uptake rate requirements as a function of growth-rate controlled by a limiting methanol feed rate in glycoengineered Pichia pastoris. The yield of biomass from methanol and the specific oxygen requirements predicted in this study compare well with values reported in the literature for wild-type P. pastoris, indicating the intrinsic nature of these yields independent of glycoengineering or the heterologous protein expressed. Specific productivity was found to be a non-linear function of specific growth rate. Based on comparison with relationships between specific growth rate and specific productivity reported in the literature this correlation seems empirical in nature and cannot be established a priori. These correlations were then used in a simple mass balance based model to predict the cultivation performance of carbon limited cultivations under oxygen transfer limited conditions to indicate the usefulness of this approach to predict large scale performance and aid in process development.

Novel (E)-α-benzylthio chalcones are reported with preliminary in vitro activity data indicating that several of them are potent inhibitors (comparable to imatinib, the reference compound) of BCR-ABL phosphorylation in leukemic K562 cells, known to express high levels of BCR-ABL. The ability of such compounds to significantly inhibit K562 cell proliferation suggests that this scaffold could be a promising lead for the development of anticancer agents that are able to block BCR-ABL phosphorylation in leukemic cells.

The growing antibody market and the pressure to improve productivity as well as reduce cost of production have fueled the development of alternative expression systems. The therapeutic function of many antibodies is influenced by N-linked glycosylation, which is affected by a combination of the expression host and culture conditions. This paper reports the generation of a glycoengineered Pichia pastoris strain capable of producing more than 1 g l(-1) of a functional monoclonal antibody in a robust, scalable and portable cultivation process with uniform N-linked glycans of the type Man(5)GlcNAc(2). N-linked glycan uniformity and volumetric productivity have been maintained across a range of cultivation process conditions including pH (5.5-7.5), temperature (16-24 degrees C), dissolved oxygen concentration (0.85-3.40 mg l(-1)) and specific methanol feed rate (9-19 mg g(-1) h(-1)) as well as across different cultivation scales (0.5, 3.0, 15 and 40 l). Compared to a marketed CHO-produced therapeutic antibody, the glycoengineered yeast-produced antibody has similar motilities on SDS-PAGE, comparable size exclusion chromatograms (SEC) and antigen binding affinities. This paper provides proof of concept that glycoengineered yeast can be used to produce functional full-length monoclonal antibodies at commercially viable productivities.

A new series of styryl acetoxyphenyl sulfides and sulfones possessing (E)- and (Z)-configurations were designed and prepared by stereospecific syntheses. All these compounds were evaluated for their ability to inhibit COX-2 enzyme in vitro. Structure-activity relationship studies on these compounds revealed that only sulfides with (Z)-configuration have potential COX-2 inhibitory activity. This inactivation of the enzyme is believed to be due to the selective covalent modification of COX-2 by the inhibitors.

β-Keto vinylic sulfones, the key building blocks for the synthesis of the title compounds, were prepared by two different routes. NaBH 4 reduction of these compounds afforded β-hydroxy vinylic sulfones which were dehydrated with acetic anhydride and BF 3 .Et 2 O to obtain bis(styryl) sulfones. Alternatively, one-pot synthesis of these bis(styryl) sulfones was also achieved directly from β-keto vinylic sulfones by treating with NaBH 4 in EtOH followed by refluxing with concentrated HCl.

Spontaneous coronary artery dissection (SCAD) is a rare cause of acute coronary syndrome. In the literature, more than 1,200 cases of SCAD have been reported, with a low rate of recurrent spontaneous coronary artery dissection (r-SCAD) described in only 63 cases. Among these patients with r-SCAD, just three cases had three separate episodes of dissection and all were in women. We report the first case of r-SCAD in men, with three episodes of dissection in different coronary arteries and review the published literature on predisposing factors for r-SCAD and its management.

Human serum albumin (HSA) is a cysteine rich molecule that is most abundant in human blood plasma. To remain viable in the market due to lower marketing costs for HSA, it is important to produce a large quantity in an economical manner by recombinant technology. The objective of this study was to maximize recombinant HSA (rHSA) production using a Mut(s) Pichia pastoris strain by fermentation process optimization. We evaluated the impact of process parameters on the production of rHSA, including induction cell density (wet cell weight, g/L) and the control of specific growth rate at induction. In this study, we demonstrated that induction cell density is a critical factor for high level production of rHSA under controlled specific growth rate. We observed higher specific productivities at higher induction cell densities (285 g/L) and at lower specific growth rates (0.0022-0.0024/h) during methanol induction phase, and achieved the broth titer of rHSA up to 10 g/L. The temperature shift from 24 to 28(o) C was effective to control the specific growth rate at low level (≤0.0024/h) during methanol induction phase while maintaining high specific productivity [0.0908 mgrHSA /(gwcw h)].

A YBa2Cu3O7/NdAlO3/YBa2Cu3O7 trilayer was grown on (100) MgO substrate by pulsed laser deposition. A SrTiO3 capping layer was used on the YBCO underlayer, which enabled growth of thick NdAlO3 dielectric layers with smooth surfaces. Layer-by-layer growth was verified by RHEED and AFM. The transition temperatures of the over- and underlayer were 91 K, with critical currents of 1.5 × 106 and 1.0 × 106 A/cm2 at 77 K, respectively. The capacitance of trilayer capacitors scaled linearly with pad area, from which the relative dielectric constant of the NdAlO3 thin film was estimated to be ∼ 21. The resistivity of the dielectric was measured to be 107 Ωcm at 77 K.

MgO/YBa2Cu3O7−x (YBCO) and YBCO/MgO/YBCO multilayers were grown on (100) LaAlO3 substrates by pulsed laser deposition. Reflection high-energy electron diffraction (RHEED), X-ray diffraction (XRD), and atomic force microscopy (AFM) were used to characterize the layers. Deposition of MgO on YBCO at elevated temperatures resulted in oxygen-deficient YBCO layers that did not exhibit a superconducting transition above 80 K. However, room-temperature growth of MgO on a fully oxygenated YBCO film with a transition temperature Tc=90 K, preserved the oxygen and superconducting properties in the YBCO underlayer. MgO deposited at room temperature on YBCO was polycrystalline, and the YBCO overlayer was amorphous. However, crystalline YBCO overlayers were obtained when a thin SrTiO3 buffer layer was used between the polycrystalline MgO and YBCO overlayer. Results of the microstructural characterization by RHEED and AFM showed that both the SrTiO3 buffer and YBCO overlayer grew in the (110) orientation. XRD studies confirmed that the c-axis of the YBCO overlayer was parallel to the growth plane.

A series of novel (E)-N-aryl-2-arylethenesulfonamides (6) were synthesized and evaluated for their anticancer activity. Some of the compounds in this series showed potent cytotoxicity against a wide spectrum of cancer cell-lines (IC50 values ranging from 5 to 10 nM) including all drug resistant cell-lines. Nude mice xenograft assays with compound (E)-N-(3-amino-4-methoxyphenyl)-2-(2',4',6'-trimethoxyphenyl)ethenesulfonamide (6t) showed dramatic reduction in tumor size, indicating their in vivo potential as anticancer agents. A preliminary drug development study with compound 6t is predicted to have increased blood-brain barrier permeability relative to many clinically used antimitotic agents. Mechanistic studies indicate that 6t and some other analogues disrupted microtubule formation, formation of mitotic spindles, and arrest of cells in mitotic phase. Compound 6t inhibited purified tubulin polymerization in vitro and in vivo and circumvented drug resistance mediated by P-glycoprotein. Compound 6t specifically competed with colchicine binding to tubulin and with similar avidity as podophylltoxin, indicating its binding site on tubulin.

Previous studies have shown that glycoproteins expressed in wild-type Pichia pastoris bind to Dendritic cell-SIGN (DC-Specific Intercellular adhesion molecule-3 Grabbing Nonintegrin), a mannose-binding receptor found on dendritic cells in peripheral tissues which is involved in antigen presentation and the initiation of an immune response. However, the binding of DC-SIGN to glycoproteins purified from P. pastoris strains engineered to express humanized N- and O-linked glycans has not been tested to date. In this study, the binding of glycoproteins with specific high-mannose or human N- and O-linked glycan structures to DC-SIGN was tested. Proteins with humanized N-glycans including Man5 structures and O-glycans (up to as many as 24) with single mannose chain length showed DC-SIGN binding that was comparable to that measured for a CHO-produced IgG1 which lacks O-linked mannose. Glycoproteins with wild-type N-glycans and mannotriose and higher O-glycans bound to DC-SIGN in a manner that was strongly inhibited by either the use of enzymatic N-deglycosylation or sodium meta-periodate oxidation. Mannan purified from humanized P. pastoris also showed lower ability to inhibit DC-SIGN binding to glycoproteins with wild type fungal glycosylation than mannan purified from wild type strains. This study shows that humanized P. pastoris can produce glycoproteins that do not bind to DC-SIGN.

Tubulin, the major structural component of microtubules, is a target for the development of anticancer agents. A series of (Z)-1-Aryl-3-arylamino-2-propen-1-one (10) were synthesized and evaluated for anti-proliferative activity in cell based assay. The most active compound (Z)-1-(2- bromo-3,4,5-trimethoxyphenyl)-3-(3-hydroxy-4-methoxyphenylamino)-prop-2-en-1-one (10ae) was tested in 20 tumor cell lines including multidrug resistant phenotype and was found to induce apoptosis in all these cell lines with similar GI50 values. Flow cytometry studies showed that 10ae arrested the cells in G2/M phase of cell cycle. In addition to G2/M block, these compounds caused microtubule stabilization like paclitaxel and induced apoptosis via activation of the caspase family. The observations made in this investigation demonstrate that (Z)-1-Aryl-3- arylamino-2-propen-1-one (10) represents a new class of microtubule – stabilizing agents.

Introduction: Recent proof-of-concept for targeting cyclin dependent kinases 4 and 6 (CDK4/6) culminated in the approval for breast cancer of the first-in-class CDK4/6 inhibitor, palbociclib (Ibrance®). Palbociclib and other potent but narrowly targeted CDK4/6 inhibitors are cytostatic rather than cytotoxic (Leonard et al, 2012), and require combination therapy for optimal activity. ON 123300 is a next-generation CDK4/6 inhibitor with improved single-agent cytotoxicity. This novel compound is a potent CDK4 and CDK6 inhibitor (IC50 = 3.9 nM and 9.8 nM, respectively) that is cytotoxic against breast and other cancer cell lines (Reddy et al, 2014). We present pre-IND profiling pharmacology, physicochemical and ADME studies to support ON 123300 as a clinical candidate and next-generation CDK4/6 inhibitor. Methods and Results: Non-clinical studies were conducted in order to assess the drug-like properties of ON 123300 and its pharmaceutical salts. Physicochemical parameters were determined for the compound. ON 123300 was highly soluble below pH 4.0, with reduced solubility in more basic conditions. Predicted intestinal absorption, as measured by Caco-2 permeability, was 1.95×10-5 cm/s with a low efflux ratio. Based on these characteristics, the compound was advanced to lead profiling against 68 primary molecular targets. Radioligand binding studies revealed limited receptor inhibition (11/68 targets) with 10 μM of ON 123300. Human Ether-a-go-go (hERG) inhibition testing revealed no significant effect (IC50 > 25 μM). In vitro metabolism studies indicated metabolism through CYP3A4 and CYP2C8. Finally, in silico based modeling (Cloe® PK) integrating all key non-clinical parameters was carried out in order to estimate the potential for oral absorption in humans. Preliminary analysis suggests good oral bioavailability and the potential to establish an acceptable therapeutic window. Conclusions: The well differentiated biochemical, anticancer and pharmaceutical properties of ON 123300 provide the basis for pre-clinical toxicology testing, leading to an investigational new drug (IND) filing and clinical exploration of this compound across tumor types that share targets accessed by this next-generation CDK inhibitor. Citation Format: Benjamin Hoffman, Ramana Reddy, Muralidhar Mallireddigari, Daniel Fox, Chen Ren, Manoj Maniar. Single-agent activity and favorable pharmaceutical properties of orally bioavailable next-generation CDK4/6 inhibitor, ON 123300. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr LB-A21.

Glycoengineering technology can elucidate and exploit glycan related structure-function relationships for therapeutic proteins. Glycoengineered yeast has been established as a safe, robust, scalable, and economically viable expression platform. It has been found that specific productivity of antibodies in glycoengineered Pichia pastoris is a non-linear function of specific growth rate that is dictated by a limited methanol feed rate. The optimal carbon-limited cultivation requires an exponential methanol feed rate with an increasing biomass concentration and more significantly an increase in heat and mass transfer requirements that often become the limiting factor in scale-up. Both heat and mass transfer are stoichiometrically linked to the oxygen uptake rate. Consequently an oxygen-limited cultivation approach was evaluated to limit the oxygen uptake rate and ensure robust and reliable scale-up. The oxygen-limited process not only limited the maximum oxygen uptake rate (and consequently the required heat removal rate) in mut+ P. pastoris strains but also enabled extension of the induction phase leading to an increased antibody concentration (1.9gL(-1) vs. 1.2gL(-1)), improved N-glycan composition and galactosylation, and reduced antibody fragmentation. Furthermore, the oxygen-limited process was successfully scaled to manufacturing pilot scale and thus presents a promising process option for the glycoengineered yeast protein expression platform.

Cell cycle progression is regulated by cyclins and cyclin-dependent kinases, which are formed at specific stages of the cell cycle and regulate the G1/S and G2/M phase transitions, employing a series of "checkpoints" governed by phosphorylation of their substrates. Tumor development is associated with the loss of these checkpoint controls, and this provides an approach for the development of therapeutic agents that can specifically target tumor cells. Here, we describe the synthesis and SAR of a novel group of cytotoxic molecules that selectively induce growth arrest of normal cells in the G1 phase while inducing a mitotic arrest of tumor cells resulting in selective killing of tumor cell populations with little or no effect on normal cell viability. The broad spectrum of antitumor activity in vitro and xenograft models, lack of in vivo toxicity, and drug resistance suggest potential for use of these agents in cancer therapy.

A series of 20 novel 1-(4-sulfamylphenyl)-3-trifluoromethyl-5-indolyl pyrazolines were designed, synthesized, and screened in vitro for anti-inflammatory activity. These compounds were designed for evaluation as dual inhibitors of cyclooxygenases (COX-1 and COX-2) and lipoxygenases (LOX-5, LOX-12, and LOX-15) that are responsible for inflammation and pain. All pyrazoline molecules prepared are optically active and compounds that are more potent in COX-2 inhibitory activity (5a and 5f) were resolved by chiral column and each enantiomer was tested for cyclooxygenase inhibitory activity. Molecular modeling and comparison of molecular models of 5a enantiomers with that of celecoxib model shows that 5a (enantiomer-1) and 5a (enantiomer-2) have more hydrogen bonding interactions in the catalytic domain of COX-2 enzyme than celecoxib. Compounds 5a, 5e, and 5f showed moderate to good LOX-5 and LOX-15 inhibitory activity and this is comparable to that of celecoxib and more potent than rofecoxib.

Thick, high-quality epitaxial trilayers of YBa2Cu3O7−x/NdAlO3/YBa2Cu3O7 were grown on (100) MgO substrates by pulsed laser deposition. Compact resonators based on such trilayers were designed, fabricated, and tested. The resonant frequencies of the resonators were varied from 1.6 to 9.4 GHz by varying the device geometry within a die size of 2×2 mm. The values of the capacitive and inductive elements of the resonator and series resistance were estimated, and the frequency response of the circuit model was simulated. The measured and simulated resonant frequencies, insertion losses, and quality factors were in agreement. The contact resistivity of the Ag-YBa2Cu3O7−x contacts at the capacitor pads was found to dominate the loss in the resonator.

A series of novel coumarin carboxamides were synthesized, and their tumor cell cytotoxic activity was investigated. These compounds specifically inhibited the growth of cancer cells that have a high level of ErbB-2 expression. Immunoprecipitation analysis of the cell lysates prepared from carboxamide treated cancer cells showed the inhibition of ErbB-2 phosphorylation suggesting the interaction of these compounds with ErbB-2 receptor. The down regulation of the kinase activity was further confirmed by performing in vitro kinase assay with recombinant ErbB-2 incubated with carboxamides. The inhibition of ErbB-2 phosphorylation correlated with down-regulation of ERK1 MAP kinase activation that is involved in proliferative signaling pathway. Furthermore, the cell-killing activity of many of these inhibitors is restricted to tumor cells with no demonstrable cytotoxicity against normal human fibroblasts suggesting that these compounds are tumor-specific.

YBa2Cu3O7−x (YBCO) films were grown on SrTiO3 buffered (100)‐MgO substrates by pulsed laser deposition. The microstructure of the SrTiO3 layers was varied by changing the growth parameters and thickness. The surface morphology of the layers was characterized by atomic force microscopy. Stripline microwave resonators were fabricated from the films, and the resonator characteristics were measured. The microwave loss in the YBCO was found to correlate to SrTiO3 grain size.

Synthesis of coumarin 3-(N-aryl) sulfonamides was accomplished either by Knoevenagel condensation of anilinosulfonylacetic acids with suitable salicylaldehydes or by the reaction of methyl anilinosulfonylacetates with substituted salicylaldehydes in presence of a catalytic amount of a base. All the compounds tested for antiproliferative activity in different cancer cell lines have shown GI(50) values less than 100 microM.

e13562 Background: The signal transducer and activator of transcription (STAT) family of proteins are important intracellular mediators. Two of these family members, STAT3 and STAT5, have been foun...

A stereoselective and efficient method for free radical addition of benzyl thiol to aryl acetylene in the presence of Et3B-hexane has been developed for the synthesis of (Z) and (E)-styryl benzyl sulfides where base catalyzed hydrothiolations have failed. The scope of this reaction was successfully extended for the synthesis of (E)-ON 01910·Na, a phase III clinical stage anti-cancer agent and its inactive geometrical isomer (Z)-ON 01910·Na. It is interesting to note that all the E-isomers synthesized have shown better cytotoxicity profile on cancer cells compared to the Z-isomers.

The case is presented of a 38-year-old male who presented with a large 10 cm x 8 cm pulsatile swelling in his abdomen. Thirteen years before, internal iliac arteries had been used to treat long segment occlusions and diseased state of both renal arteries. At the same time both kidneys had been transplanted to the iliac fossae. Digital subtraction angiography revealed a huge abdominal aortic aneurysm. Both kidneys were fully functional. As the renal transplants had been done extraperitoneally an easy transperitoneal approach was now possible. The maximum diameter of the aneurysm was 12 cm. An inclusion graft repair was carried out using a 16-mm woven Dacron graft. In the light of the favourable circumstances it was decided not to take any special protective measures against renal ischemia apart from keeping the aortic cross-clamp time short. The patient could be discharged with patent and normally functioning kidneys 10 days after surgery.

The masking of additive noise by vowel sounds is relevant to speech coding. Since the spectral density of vowels is relatively low, and varies inversely with fundamental frequency, it may limit the masking effectiveness of vowels. In this paper, an excitation‐pattern (EP) approach (Moore and Glasberg, 1987) is used to model effects of spectral density on masking. EP predictions were obtained for masker densities ranging from 1.0 spectral component per Hz to 1.0 per 220 Hz, and target densities ranging from 1.0 component per Hz to 1.0 per 220 Hz. In all conditions, the overall power of masker and targets was 64.0 and 50.3 dB, respectively. For each combination of masker and target density, the EPs of the masker alone (EPm) and of the masker‐plus‐target (EPm+t) were obtained. The EP difference, EPD=(EPm+t)−(EPm), at each ERB was integrated (across all ERBs) to obtain an index of target detectability. For masker densities lower than ∼1.0 component per 100 Hz, detectability improved as masker density decrease...

An important issue in audio coding is the detection of quantization noise masked by speech. This investigation examined how different frequency regions contribute to the detection of broadband noise masked by a vowel. The vowel was synthesized by addition of the first 32 harmonics of a 200‐Hz fundamental, with amplitudes appropriate to /i/. Broadband noise was synthesized by random‐phase addition of the harmonics of a 10‐Hz fundamental that fall within the vowel bandwidth. Noise detection thresholds were measured in a 2IFC task with an adaptive procedure (Levitt, 1971). Detection thresholds were obtained for noise with spectrum envelope parallel to that of the vowel, and for the same noise containing −6.0‐dB spectral notches in either of the following bands: (a) 0.2–0.5 kHz; (b) 0.2–1.0 kHz; (c) 4.2–5.0 kHz; and (d) 4.7–5.0 kHz. Thresholds obtained in three highly trained listeners ranged from −27 to −32 dB (expressed in terms of noise‐to‐vowel power ratio). Threshold differences between spectral notch conditions were small. The results were compared to predictions of the excitation pattern model proposed by Moore and Glasberg [Hear. Res. 28, 209–225 (1987)]. [Work supported by OCAST‐HR4‐064.]

This study examines some advantages of adaptive psychophysical tests for obtaining reliable and efficient estimates of speech quality. Specifically, in vowels corrupted by additive noise, noise‐detection thresholds were measured adaptively. The 350‐ms vowels were obtained by addition of the first 32–35 harmonics of 100–200 fundamental frequencies, with spectral envelopes appropriate for /i/ and /a/. Noise was synthesized by random‐phase addition of harmonics of a 10‐Hz fundamental; the noise bandwidth and the spectral envelope were equal to those of the vowels. In a 2IFC task, subjects had to determine the observation interval that contained a ‘‘noisy vowel.’’ During a block of trials, the noise level was varied using a ‘‘two‐down, one‐up’’ rule (Levitt, 1971); the test terminated when the subject completed 6–8 reversals, and thresholds were defined as the average noise level obtained in the last three reversals. The adaptive method yielded threshold estimates in much fewer trials than a constant stimuli ...

Directed evolution is a new process for developing industrially viable biocatalysts. This technique does not require a comprehensive knowledge of the relationships between sequence structure and function of proteins as required by protein engineering. It mimics the process of Darwinian evolution in a test tube combining random mutagenesis and recombination with screening or selection for enzyme variants that have the desired properties. Directed evolution helps in enhancing the enzyme performance both in natural and synthetic environments. This article reviews the process of directed evolution and its application to improve substrate specificity, activity, enantioselectivity and thermal stability.

[No abstract available]