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A focus on the gray market activity and a study on the role of enforcement in discouraging and avoiding gray market incidents are presented.

Using research in social psychology, the authors illustrate how two key routes to improve communication between marketing and engineering are dependent on the strength of managers' psychological connection to their functional area compared to the firm as a whole (i.e., relative functional identification). In particular, they argue that relative functional identification moderates the relationship between strategies traditionally used to affect interfunctional relationships (information-sharing norms and integrated goals) and the frequency, bidirectionality, and coerciveness of interfunctional communication behaviors. In turn, these communication behaviors are linked to information use and perceived relationship effectiveness. The authors empirically test predictions of the framework in two studies. Study 1 results suggest that (1) the efficacy of the traditional strategies depends on marketing managers' relative functional identification and (2) the traditional strategies can have negative and unintended effects on communication behaviors. In Study 2, the authors replicate and extend Study 1 by illustrating that bidirectional communication is as important as frequency in increasing both information use by engineering personnel and the perceived effectiveness of interfunctional relationships. The authors conclude with implications for theory building and managerial practice.

Governance strategies, such as integration or control, structure and regulate the conduct of parties in exchange relationships; as such, they serve to constrain the latitude of the decision making of channel partners. Similarly, collaborative communication can be used to create an atmosphere of mutual support, thereby creating volitional compliance between partners. The authors develop a model that addresses the interrelationships of governance and communication and examine the effects of collaborative communication on channel outcomes (the dealer's perceptions of commitment to, satisfaction with, and coordination of activities with a focal manufacturer) across various levels of integration and control. Based on survey data collected from a national sample of computer dealers, the findings indicate that when levels of integration or manufacturer control are high, the effect of collaborative communication on outcomes is weaker than when integration or control is low. (Reprinted by permission of the publisher.)

ONCE upon a time, those who dispensed legal counsel and services were able to build successful businesses because they worked hard, served their clients well, had good reputations and were [...]

The National Defense Center for Energy and Environment (NDCEE) (1) and the U.S. Army Environmental Command (USAEC) (2) recently assisted four Army facilities in switching to two improved chemical agent-resistant [...]

The described oxime-based library protocol provides detailed procedures for the linkage of aminooxy functionality with aldehyde building blocks that result in the generation of libraries of multidentate inhibitors. Synthesis of inhibitors for protein tyrosine phosphatases (PTPs) and antagonists directed against the human tumor susceptibility gene 101 (TSG101) are shown as examples. Three steps are involved: (i) the design and synthesis of aminooxy platforms; (ii) tethering with aldehydes to form oxime-based linkages with sufficient purity; and (iii) direct in vitro biological evaluation of oxime products without purification. Each coupling reaction is (i) performed in capped microtubes at room temperature (20–23 °C); (ii) diluted for inhibitory evaluation; and (iii) screened with targets in microplates to provide IC50or Kdvalues. The synthesis of the aminooxy platforms takes 3–5 d; tethering with the aldehydes takes 24 h; and inhibition assay of enzymes and protein-protein interactions takes 30 min and 2 h, respectively.

Improved methods have recently been developed for assessing islet viability and quantity in human islet preparations for transplantation, and these measurements have proven useful for predicting transplantation outcome. The objectives of this study were to adapt these methods for use with microencapsulated islets, to verify that they provide meaningful quantitative measurements, and to test them with two model systems: (1) barium alginate and (2) barium alginate containing a 70% (w/v) perfluorocarbon (PFC) emulsion, which presents challenges to use of these assays and is of interest in its own right as a means for reducing oxygen supply limitations to encapsulated tissue. Mitochondrial function was assessed by oxygen consumption rate measurements, and the analysis of data was modified to account for the increased solubility of oxygen in the PFC-alginate capsules. Capsules were dissolved and tissue recovered for nuclei counting to measure the number of cells. Capsule volume was determined from alginate or PFC content and used to normalize measurements. After low oxygen culture for 2 days, islets in normal alginate lost substantial viable tissue and displayed necrotic cores, whereas most of the original oxygen consumption rate was recovered with PFC alginate, and little necrosis was observed. All nuclei were recovered with normal alginate, but some nuclei from nonrespiring cells were lost with PFC alginate. Biocompatibility tests revealed toxicity at the islet periphery associated with the lipid emulsion used to provide surfactants during the emulsification process. We conclude that these new assay methods can be applied to islets encapsulated in materials as complex as PFC-alginate. Measurements made with these materials revealed that enhancement of oxygen permeability of the encapsulating material with a concentrated PFC emulsion improves survival of encapsulated islets under hypoxic conditions, but reformulation of the PFC emulsion is needed to reduce toxicity.

The article provides a discussion on the properties of the center of mass, explores all the points in the plane which have the same property, and takes into consideration few natural generalizations. It is noted that the primary driving force for the research's results is the proof of property for the circle. Moreover, the author also discusses the finding of the research from different angles and traces some applicable generalizations.

The dramatic progress in mass spectrometry-based methods of protein identification has triggered a new quest for disease-associated biomarkers. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and its variant surface-enhanced laser desorption/ionization mass spectrometry, provide effective means to explore the less studied information slice of the human serum proteome – low-molecular-weight proteins and peptides. These low-molecular-weight proteins and peptides are promising for the detection of important biomarkers. Due to the significant experimental problems imposed by high-abundance and high-molecular-weight proteins, it is important to effectively remove these species prior to mass spectrometry analysis of the low-molecular-weight serum and plasma proteomes. In this review, the advantages afforded by recently introduced methods for prefractionation of serum, as they pertain to the detection and identification of biomarkers, will be discussed.

Protein kinase C (PKC)-theta, a member of the ‘novel’ subfamily of PKC isoforms, is of singular importance in transducing signals in T-lymphocytes. Since understanding of regulatory phosphorylation of novel PKCs is fragmentary and inconsistent with findings for ‘classical’ PKC isoforms, we investigated three potential phosphorylation sites on PKC-theta; in the activation loop (Thr538), turn motif (Ser676) and hydrophobic motif (Ser695). Combined evidence from phospho-specific antisera and MS demonstrates phosphorylation at all three sites. Unlike its closest paralogue, PKC-delta, lack of negative charge in the activation loop of PKC-theta results in a profound catalytic defect (>100-fold reduction in the T538A mutant); the high sequence similarity between PKC-theta and -delta assists in the formulation of structural hypotheses to account for this major difference. In contrast with mechanisms proposed for other PKC isoforms, phosphorylation at the other two sites does not reconstitute catalytic activity. Activation loop phosphorylation is critical invivo, since the T538A mutant completely lost its capacity to mediate T-cell receptor-stimulation of nuclear factor κB (NF-κB) activation in Jurkat T-cells. Hydrophobic motif phosphorylation also substantially influences PKC-theta catalytic activity (5-fold reduction in the S695A mutant), but does not impair NF-κB activation in Jurkat T-cells. Its mechanism is independent of secondary effects on activation loop phosphorylation and cannot be explained by thermal instability. Turn motif phosphorylation has a limited effect on kinase activity, but negatively regulates other aspects of PKC-theta function, since the S676A mutant is more efficient than wild-type in inducing NF-κB activation in Jurkat T-cells. These findings expand our understanding of the roles of phosphorylation in novel PKCs, and indicate that PKC-theta is a constitutively competent kinase as a consequence of constitutive phosphorylation of its activation loop.

ABSTRACTTrophic factor withdrawal induces cell death by mechanisms that are incompletely understood. Previously we reported that withdrawal of interleukin-7 (IL-7) or IL-3 produced a rapid intracellular alkalinization, disrupting mitochondrial metabolism and activating the death protein Bax. We now observe that this novel alkalinization pathway is mediated by the pH regulator NHE1, as shown by the requirement for sodium, blocking by pharmacological inhibitors or use of an NHE1-deficient cell line, and the altered phosphorylation of NHE1. Alkalinization also required the stress-activated p38 mitogen-activated protein kinase (MAPK). Inhibition of p38 MAPK activity with pharmacological inhibitors or expression of a dominant negative kinase prevented alkalinization. Activated p38 MAPK directly phosphorylated the C terminus of NHE1 within a 40-amino-acid region. Analysis by mass spectroscopy identified four phosphorylation sites on NHE1, Thr 717, Ser 722, Ser 725, and Ser 728. Thus, loss of trophic cytokine signaling induced the p38 MAPK pathway, which phosphorylated NHE1 at specific sites, inducing intracellular alkalinization.

The human endogenous retrovirus, type K (HERV-K) represents the most biologically active form of known retroelements present in the human genome. Several HERV-K genomes have transcriptionally active open reading frames and encode their own protease (PR). The HERV-K PR has been shown to authentically cleave human immunodeficiency virus type 1 (HIV-1) matrix-capsid peptide in the presence of HIV-1 PR inhibitors. This raised the possibility that HERV-K PR could complement HIV-1 PR function in HIV-1-infected individuals. To investigate this possibility, we fused the HIV-1 vpr gene to the HERV-K PR gene (vpr-PR). The vpr-PR expression plasmid and a PR-defective HIV-1 clone were cotransfected into 293T cells. Progeny virions were assayed for processing of the HIV-1 polyproteins by Western blot and for changes in infectivity. HERV-K PR fused to Vpr was incorporated into HIV-1 virions at a high concentration and cleaved the Gag and Pol precursor proteins. However, neither Gag nor Pol polyproteins were correctly processed. Moreover, the HERV-K PR did not restore virus infectivity. While these results do not exclude the possibility that the HERV-K PR could complement an HIV-1 PR whose function is impaired due to drugs or drug-resistant mutations, they clearly demonstrate that the HERV-K PR cannot substitute for the function of the wild-type HIV-1 PR.

We have developed a complete system for discovery of lead compounds as inhibitors of creatine kinase B. In this article, we describe production and purification of the recombinant protein, conditions and features of an optimized high-throughput screening assay, and results of our implementation of the system using a diverse compound library. Copyright 2000 Academic Press.

Host proteins are incorporated both on and inside human immunodeficiency virus type 1 (HIV-1) virions. To identify cellular proteins inside HIV-1, virion preparations were treated by a protease-digestion technique that removes external host proteins, allowing for the study of the proteins inside the virus. Treated HIV-1 preparations were analyzed by immunoblot, high-pressure liquid chromatography, and protein sequence analyses. These analyses identified several cellular proteins inside HIV-1: elongation factor 1α, glyceraldehyde-3-phosphate dehydrogenase, HS-1, phosphatidylethanolamine-binding protein, Pin1, Lck, Nm23-H1, and the C-terminal tail of CD43. Several of these proteins were found as fragments of their full-sized proteins that appear to be generated by our protease treatment of the virions, the HIV-1 protease, or a cellular protease. Recent advances in cell biology and biochemistry have identified some of these proteins as actin-binding proteins. These results support the hypothesis that actin filaments are incorporated into the virion and may provide additional clues for the understanding of the interaction between viral and cellular proteins during assembly and budding.

We have developed a facile means for the refolding of milligram quantities of purified proteins that employs gel filtration chromatography. We demonstrate by electrophoretic mobility shift and NMR spectroscopy that human ETS-1 protein, bovine ribonucelase A and E. coliintegration host factor can be refolded into the native conformation using this technique. We have extended this strategy to the preparation of miligram quantities of macromolecular complexes suitable for structural analysis by NMR spectroscopy or X-ray crystallography. The diverse challenges to overcome in refolding these proteins illustrates the potential of this technique as a general approach for recovery of recombinant proteins produced as insoluble inclusion bodies.

ABSTRACTWe have analyzed the binding of recombinant human immunodeficiency virus type 1 nucleocapsid protein (NC) to very short oligonucleotides by using surface plasmon resonance (SPR) technology. Our experiments, which were conducted at a moderate salt concentration (0.15 M NaCl), showed that NC binds more stably to runs of d(G) than to other DNA homopolymers. However, it exhibits far more stable binding with the alternating base sequence d(TG)nthan with any homopolymeric oligodeoxyribonucleotide; thus, it shows a strong sequence preference under our experimental conditions. We found that the minimum length of an alternating d(TG) sequence required for stable binding was five nucleotides. Stable binding to the tetranucleotide d(TG)2was observed only under conditions where two tetranucleotide molecules were held in close spatial proximity. The stable, sequence-specific binding to d(TG)nrequired that both zinc fingers be present, each in its proper position in the NC protein, and was quite salt resistant, indicating a large hydrophobic contribution to the binding. Limited tests with RNA oligonucleotides indicated that the preferential sequence-specific binding observed with DNA also occurs with RNA. Evidence was also obtained that NC can bind to nucleic acid molecules in at least two distinct modes. The biological significance of the specific binding we have detected is not known; it may reflect the specificity with which the parent Gag polyprotein packages genomic RNA or may relate to the functions of NC after cleavage of the polyprotein, including its role as a nucleic acid chaperone.

The Pharmacia BlAcore biosensor was used to measure the real-time interaction of Escherichia coliSSB protein with poly(deoxythymidylic acid), (dT)70. The rationale for an experimental protocol for this type of binding reaction is presented. This approach may have general applicability in the design and analysis of BiAcore binding experiments. A chip is modified with three different surface densities of biotinylated oligonucleotide and a fourth channel is modified with only streptavidin. This allows examination of collected data for surface crowding effects, for flow limiting or reaction limiting binding, and for surface saturation. These observations are used to develop a mathematical model to describe the family of sensorgrams from a series of surface densities and protein concentrations with a single set of parameters. Each part of the model, as well as its relationship to the overall binding reaction, is described. The model presented is consistent with kinetic data for the association and dissociation rate constants for E. coliSSB and permits calculation of a thermodynamic binding constant. The concept of steric cooperativity is introduced to explain the observed increasing rate of binding as the surface binds more SSB protein.

A nitrogenase system that remains in the supernatant fluid after centrifuging for 3 hr at 180,000 × gcan be extracted from Azotobacter vinelandiiby osmotic lysis of the bacteria. This nitrogenase preparation is oxygen-labile and appears to be similar, though not identical, to that obtained from Clostridium pasteurianum. The particulate characteristic and oxygen stability of previously described preparations are likely due to the method of cell disruption, e.g., in the French pressure cell. The data support a nitrogenase model system in the intact cell in which oxygen-labile enzymes are protected from oxygen by the extensive internal membranous system which Azotobactersynthesize only when they fix nitrogen.

The highly purified soluble ATP synthetase complex from mitochondria, containing energy-transfer Factor A (the terminal ADP phosphorylation enzyme of oxidative phosphorylation) and Factor D, catalyzes ATP-Piand ATP-ADP exchange reactions. The ATP-Piexchange activity is inhibited by low concentrations of the uncouplers of oxidative phosphorylation, oligomycin and p-chloromercnriphenylsulfonate. It is stimulated threefold by dithiothreitol and is Mg++dependent. Antiserum to coupling factor 1 (F1) also inhibits the ATP-Piexchange. The ATP-ADP exchange activity appears to be greater than the ATP-Piexchange activity. The results suggest that the nonphosphorylated high-energy intermediate (X∼C), and possibly the phosphorylated intermediate (X∼P), are formed on the synthetase. Sites of uncoupler and oligomycin action reside in the terminal ATP synthetase.

The article discusses the advantages of rules-based decision-making or naked decision-making for investors. The method requires following rules that have been created by experts to help avoid previous mistakes made by investors. Naked decision-making is said to minimize the effects of emotions, bias and systemic thinking errors often committed by investors.

Ultrasound frequencies ranging from 26 kHz–10 MHz are used in a number of applications varying from cell disruptions to therapeutic and diagnostic procedures. Previous results from our laboratory have demonstrated that 1‐MHz ultrasound at therapeutic intensities causes significant changes in the electrophysiological properties of epithelial tissues. The nature of these alterations indicated that, among other effects, the Na/K‐dependent ATPase activity of the tissue was reduced. In this study, the effects of ultrasonic irradiation (30 kHz) on enzyme activities in two model systems have been examined: one membrane incorporated (Na/K‐dependent ATPase in inverted erythrocyte ghosts from rat blood) and the other in ‘‘free’’ solution (ATP‐dependent firefly luciferin/luciferase reaction). Ultrasonic irradiation produced irreversible decreases in the activity of the enzyme in each system. At present, the analysis leads one to conclude that sono‐chemical (including free radical) and not thermal effects on the enzyme molecules are responsible for the activity decreases. These results support the hypothesis that the effects of ultrasonic irradiation were, in part, due to effects on the activity of Na/K‐dependent ATPase. Furthermore, the results of this study demonstrate that sono‐chemical‐induced enzyme activity changes may represent a much more common and pervasive effect than is commonly realized. [Work supported by the NIH under Grant No. 5‐RO1‐CA‐39374‐05.]