What Will Technology Do to Financial Structure?

This paper looks at how advances in information and telecommunications technologies have been changing the structure of the financial system by lowering transaction costs and reducing asymmetric information. Households and smaller businesses can now raise funds in securities markets as financial institutions have become better at unbundling risks while financial products can be distributed more efficiently through electronic networks. These changes have reduced the role of traditional financial intermediaries overall efficiency by lowering the costs of financial contracting. Despite these benefits technological progress presents policymakers with some important challenges. First markets for financial products become larger and more contestable, defining geographic and product markets narrowly becomes more problematic. Second, financial consolidation and the trend towards new activities of financial intermediaries require the exploration of new methods to preserve the safety and soundness of the financial system. A combined system of vigilant supervision and constructive ambiguity to deal with failures of larger institutions should be capable of mitigating the potential for increased risk-taking and help preserve the health of the financial system.

Hyaluronic acid gel fillers in the management of facial aging

Time affects facial aging by producing cellular and anatomical changes resulting in the consequential loss of soft tissue volume. With the advent of new technologies, the physician has the opportunity of addressing these changes with the utilization of dermal fillers. Hyaluronic acid (HA) dermal fillers are the most popular, non-permanent injectable materials available to physicians today for the correction of soft tissue defects of the face. This material provides an effective, non invasive, non surgical alternative for correction of the contour defects of the face due to its enormous ability to bind water and easiness of implantation. HA dermal fillers are safe and effective. The baby-boomer generation, and their desire of turning back the clock while enjoying an active lifestyle, has expanded the popularity of these fillers. In the US, there are currently eight HA dermal fillers approved for commercialization by the Food and Drug Administration (FDA). This article reviews the innate properties of FDA-approved HA fillers and provides an insight on future HA products and their utilization for the management of the aging face

Increasing Hydrophobicity of Residues in an Anti-HIV-1 Env Peptide Synergistically Improves Potency

AbstractT-20/Fuzeon/Enfuvirtide (ENF), a peptide inhibitor of HIV-1 infection, targets the grooves created by heptad repeat 2 (HR2) of Env's coiled-coil, but mutants resistant to ENF emerge. In this study, ENF-resistant mutants—V38A, N43D, N43D/S138A, Q40H/L45M—were combined with modified inhibitory peptides to identify what we believe to be novel ways to improve peptide efficacy. V38A did not substantially reduce infectivity, but was relatively resistant to inhibitory peptides. N43D was more resistant to inhibitory peptides than wild-type, but infectivity was reduced. The additional mutation S138A (N43D/S138A) increased infectivity and further reduced peptide inhibitory potency. It is concluded that S138A increased binding of HR2/ENF into grooves and that S138A compensated for electrostatic repulsion between N43D and HR2. The six-helix bundle structure indicated that E148A should increase hydrophobic interactions between the coiled-coil and peptide. Importantly, the modifications S138A and E148A in the same peptide retained potency against ENF-escape mutants. The double mutant's increase in potency was greater than the increases from the sum of S138A and E148A individually, showing that these two altered residues synergistically contributed to peptide binding. Isothermal titration calorimetry established that hydrophobic substitutions at positions S138 and E148 improved potency of inhibitory peptides against escape mutants by increasing enthalpic release of energy upon peptide binding

Substrate Influences Turtle Nest Temperature, Incubation Period, and Offspring Sex Ratio in the Field

Temperature-dependent sex determination, where egg incubation temperature irreversibly determines offspring sex, is a common sex-determining mechanism in reptiles. Weather is the primary determinant of temperature in reptile nests, yet the effects of weather are mediated through the nest microhabitat selected by the mother (e.g., overstory canopy cover). One potentially important aspect of the nest microhabitat is the physical substrate used for nesting. However, the influence of substrate type on nest temperature and offspring sex determination has never been experimentally assessed in the field. We incubated eggs of Painted Turtles (Chrysemys picta) in three substrate types similar to those commonly selected for nesting within our study population. Within a single study site, we constructed pits, which we refilled with loam, sand, or gravel. Then, we created artificial nests in each substrate type, and randomly assigned eggs to a substrate treatment. Substrate type influenced nest temperature and soil moisture, and affected incubation duration, but no other phenotype measured beyond offspring sex ratios. The cooler loam yielded the most male-biased outcome. This finding illustrates the potential importance of nesting substrate as a component of nest-site choice and as a factor in modeling future nest temperature scenarios

Simultaneous measurement of Ca2+ release and influx into smooth muscle cells in response to caffeine. A novel approach for calculating the fraction of current carried by calcium

Activation of ryanodine receptors on the sarcoplasmic reticulum of single smooth muscle cells from the stomach muscularis of Bufo marinus by caffeine is accompanied by a rise in cytoplasmic [Ca2+] ([Ca2+]i), and the opening of nonselective cationic plasma membrane channels. To understand how each of these pathways contributes to the rise in [Ca2+]i, one needs to separately monitor Ca2+ entry through them. Such information was obtained from simultaneous measurements of ionic currents and [Ca2+]i by the development of a novel and general method to assess the fraction of current induced by an agonist that is carried by Ca2+. Application of this method to the currents induced in these smooth muscle cells by caffeine revealed that approximately 20% of the current passing through the membrane channels activated following caffeine application is carried by Ca2+. Based on this information we found that while Ca2+ entry through these channels rises slowly, release of Ca2+ from stores, while starting at the same time, is much faster and briefer. Detailed quantitative analysis of the Ca2+ release from stores suggests that it most likely decays due to depletion of Ca2+ in those stores. When caffeine was applied twice to a cell with only a brief (30 s) interval in between, the amount of Ca2+ released from stores was markedly diminished following the second caffeine application whereas the current carried in part by Ca2+ entry across the plasma membrane was not significantly affected. These and other studies described in the preceding paper indicate that activation of the nonselective cation plasma membrane channels in response to caffeine was not caused as a consequence of emptying of internal Ca2+ stores. Rather, it is proposed that caffeine activates these membrane channels either by direct interaction or alternatively by a linkage between ryanodine receptors on the sarcoplasmic reticulum and the nonselective cation channels on the surface membrane

Caffeine activates a Ca(2+)-permeable, nonselective cation channel in smooth muscle cells

The effects of caffeine on cytoplasmic [Ca2+] ([Ca2+]i) and plasma membrane currents were studied in single gastric smooth muscle cells dissociated from the toad, Bufo marinus. Experiments were carried out using Fura-2 for measuring [Ca2+]i and tight-seal voltage-clamp techniques for recording membrane currents. When the membrane potential was held at -80 mV, in 15% of the cells studied caffeine increased [Ca2+]i without having any effect on membrane currents. In these cells ryanodine completely abolished any caffeine induced increase in [Ca2+]i. In the other cells caffeine caused both an increase in [Ca2+]i and activation of an 80-pS nonselective cation channel. In this group of cells ryanodine only partially blocked the increase in [Ca2+]i induced by caffeine; moreover, the change in [Ca2+]i that did occur was tightly coupled to the time course and magnitude of the cation current through these channels. In the presence of ryanodine, blockade of the 80-pS channel by GdCl3 or decreasing the driving force for Ca2+ influx through the plasma membrane by holding the membrane potential at +60 mV almost completely blocked the increase in [Ca2+]i induced by caffeine. Thus, the channel activated by caffeine appears to be permeable to Ca2+. Caffeine activated the cation channel even when [Ca2+]i was clamped to below 10 nM when the patch pipette contained 10 mM BAPTA suggesting that caffeine directly activates the channel and that it is not being activated by the increase in Ca2+ that occurs when caffeine is applied to the cell. Corroborating this suggestion were additional results showing that when the membrane was depolarized to activate voltage-gated Ca2+ channels or when Ca2+ was released from carbachol-sensitive internal Ca2+ stores, the 80-pS channel was not activated. Moreover, caffeine was able to activate the channel in the presence of ryanodine at both positive and negative potentials, both conditions preventing release of Ca2+ from stores and the former preventing its influx. In summary, in gastric smooth muscle cells caffeine transiently releases Ca2+ from a ryanodine-sensitive internal store and also increases Ca2+ influx through the plasma membrane by activating an 80-pS cation channel by a mechanism which does not seem to involve an elevation of [Ca2+]i