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Primary Effect (primary + effect)
Selected AbstractsUse of Intraoperative Botulinum Toxin in Facial ReconstructionDERMATOLOGIC SURGERY, Issue 2 2009TIMOTHY CORCORAN FLYNN MD BACKGROUND Botulinum toxin is a potent neuromodulator that temporarily relaxes muscles and can improve wound healing. OBJECTIVE This retrospective analysis assessed the use of intraoperative botulinum toxin type A or B in patients undergoing surgical reconstruction after Mohs micrographic surgery for treatment of skin cancer. The primary effect of intradermal botulinum toxin on wound healing was also studied. METHODS & MATERIALS Charts of patients who received intraoperative botulinum toxin type A (n=9) or B (n=9) in conjunction with reconstructive surgery after Mohs micrographic surgery were reviewed. Three volunteers also underwent dermal injections of botulinum toxin type A followed by erbium laser resurfacing. RESULTS Outcomes did not differ in patients treated with botulinum toxin type A and type B. Patients had excellent apposition of wound edges and smooth skin overlying soft tissue; no significant complications were noted. Healing of erbium laser ablation did not differ between botulinum toxin type A,treated skin and control skin. CONCLUSIONS Administration of botulinum toxin type A or B after reconstruction after Mohs micrographic surgery aided wound healing; botulinum toxin type A and botulinum toxin type B were equally effective. Intradermal botulinum toxin type A demonstrated no primary effect on healing of erbium laser,resurfaced skin. [source] Environmental features influencing Carabid beetle (Coleoptera) assemblages along a recently deglaciated area in the Alpine regionECOLOGICAL ENTOMOLOGY, Issue 6 2007MAURO GOBBI Abstract 1.,The spatio-temporal approach was used to evaluate the environmental features influencing carabid beetle assemblages along a chronosequence of an Italian Alpine glacier foreland. The influence of environmental variables on species richness, morphology (wing and body length), and distribution along the chronosequence was tested. 2.,Species richness was found to be a poor indicator of habitat due to weak influences by environmental variables. It seems that the neighbouring habitats of a glacier foreland are not able to determine significant changes in carabid species richness. 3.,Instead it appears that history (age since deglaciation) and habitat architecture of a glacier foreland are strongly correlated to species adaptive morphological traits, such as wing morphology and body length. Assemblages characterised by species with reduced wing size are linked to the older stages of the chronosequence, where habitat is more structured. Assemblages characterised by the largest species are linked to the younger sites near the glacier. These morphological differentiations are explained in detail. 4.,Habitat age can therefore be considered the main force determining assemblage composition. On the basis of the relationship between morphological traits and environmental variables, it seems likely that age since deglaciation is the main variable influencing habitat structure (primary effect) on the Forni foreland. The strong relationship between carabid assemblages and habitat type indicates that site age has but a secondary effect on carabid assemblages. This may be utilised to interpret potential changes in assemblages linked to future glacier retreat. [source] Sodium channel SCN1A and epilepsy: Mutations and mechanismsEPILEPSIA, Issue 9 2010Andrew Escayg Summary Mutations in a number of genes encoding voltage-gated sodium channels cause a variety of epilepsy syndromes in humans, including genetic (generalized) epilepsy with febrile seizures plus (GEFS+) and Dravet syndrome (DS, severe myoclonic epilepsy of infancy). Most of these mutations are in the SCN1A gene, and all are dominantly inherited. Most of the mutations that cause DS result in loss of function, whereas all of the known mutations that cause GEFS+ are missense, presumably altering channel activity. Family members with the same GEFS+ mutation often display a wide range of seizure types and severities, and at least part of this variability likely results from variation in other genes. Many different biophysical effects of SCN1A -GEFS+ mutations have been observed in heterologous expression systems, consistent with both gain and loss of channel activity. However, results from mouse models suggest that the primary effect of both GEFS+ and DS mutations is to decrease the activity of GABAergic inhibitory neurons. Decreased activity of the inhibitory circuitry is thus likely to be a major factor contributing to seizure generation in patients with GEFS+ and DS, and may be a general consequence of SCN1A mutations. [source] The influence of statin characteristics on their safety and tolerabilityINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 10 2004G. De Angelis Summary The efficacy of the statins for both primary and secondary prevention has now been clearly established in patients across the spectrum of cardiovascular risk. In addition to their primary effect in reducing plasma cholesterol, the statins possess various ,pleiotropic' effects that may contribute to their clinical effectiveness in reducing cardiovascular events, e.g. improvement of endothelial function, reduction of low-density lipoprotein-cholesterol oxidation and stabilisation of atheromatous plaques. Although statins share similar chemical characteristics, they differ significantly in terms of their molecular synthesis, solubility and pharmacokinetic behaviour and metabolism. Side-effects secondary to long-term statin therapy are rare, but rhabdomyolysis may occur when statins are administered together with other drugs that have a direct toxic effect on muscle or which inhibit statin metabolism. Among the various statins, it would appear that fluvastatin has the lowest propensity to interact with other drugs and the least potential to induce myotoxicity. [source] DISAPPEARING DIVIDENDS: CHANGING FIRM CHARACTERISTICS OR LOWER PROPENSITY TO PAY?JOURNAL OF APPLIED CORPORATE FINANCE, Issue 1 2001Eugene F. Fama The proportion of U.S. firms paying dividends drops sharply during the 1980s and 1990s. Among NYSE, AMEX, and Nasdaq firms, the proportion of dividend payers falls from 66.5% in 1978 to only 20.8% in 1999. The decline is due in part to an avalanche of new listings that tilts the population of publicly traded firms toward small firms with low profitability and strong growth opportunities,the timeworn characteristics of firms that typically do not pay dividends. But this is not the whole story. The authors' more striking finding is that, no matter what their characteristics, firms in general have become less likely to pay dividends. The authors use two different methods to disentangle the effects of changing firm characteristics and changing propensity to pay on the percent of dividend payers. They find that, of the total decline in the proportion of dividend payers since 1978, roughly one-third is due to the changing characteristics of publicly traded firms and two-thirds is due to a reduced propensity to pay dividends. This lower propensity to pay is quite general,dividends have become less common among even large, profitable firms. Share repurchases jump in the 1980s, and the authors investigate whether repurchases contribute to the declining incidence of dividend payments. It turns out that repurchases are mainly the province of dividend payers, thus leaving the decline in the percent of payers largely unexplained. Instead, the primary effect of repurchases is to increase the already high payouts of cash dividend payers. [source] Does infectious disease influence the efficacy of marine protected areas?JOURNAL OF APPLIED ECOLOGY, Issue 4 2005A theoretical framework Summary 1Marine protected areas are increasingly being recommended as an essential component of the management of exploited marine species, but virtually no attention has been given to the influence of parasites. This may be substantial, as a primary effect of marine reserves is to increase the density of an exploited population within the reserve relative to outside the reserve, which may facilitate parasite transmission. 2We used a simple deterministic model of microparasitic infection in a fishery with a reserve to investigate equilibrium yield and parasite prevalence inside and outside the reserve as a function of three control variables: the proportion of habitat inside the reserve, fishing mortality and the rate of interchange between the stock and the reserve. 3While our model is generic, we parameterized it with values that may be appropriate to the interaction between abalone and Rickettsia. 4The presence of a pathogen does not necessarily decrease yield when a reserve is present, particularly if the rate of movement of adult hosts between stock and reserve is low. 5Synthesis and applications. Pathogens have important implications for the design of marine reserves. Our modelling identifies two key considerations. First, ,fishing out' a pathogen by reducing the host population density to a level below the threshold for disease maintenance is a potential management strategy that is made more difficult by establishing a reserve. Secondly, the effect of a highly transmissible pathogen without a reserve is to cause a rapid decline in equilibrium yield for efforts beyond those that produce maximum sustainable yield, making the fishery prone to collapse. Introducing a reserve decreases yield in this case, but makes the fishery much more resistant to collapse. [source] Metabolic effects of p -coumaric acid in the perfused rat liverJOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 1 2006Leonardo C.N. Lima The p -coumaric acid, a phenolic acid, occurs in several plant species and, consequently, in many foods and beverages of vegetable origin. Its antioxidant activity is well documented, but there is also a single report about an inhibitory action on the monocarboxylate carrier, which operates in the plasma and mitochondrial membranes. The latter observation suggests that p -coumaric acid could be able to inhibit gluconeogenesis and related parameters. The present investigation was planned to test this hypothesis in the isolated and hemoglobin-free perfused rat liver. Transformation of lactate and alanine into glucose (gluconeogenesis) in the liver was inhibited by p -coumaric acid (IC50 values of 92.5 and 75.6 ,M, respectively). Transformation of fructose into glucose was inhibited to a considerably lower degree (maximally 28%). The oxygen uptake increase accompanying gluconeogenesis from lactate was also inhibited. Pyruvate carboxylation in isolated intact mitochondria was inhibited (IC50 = 160.1 ,M); no such effect was observed in freeze,thawing disrupted mitochondria. Glucose 6-phosphatase and fructose 1,6-bisphosphatase were not inhibited. In isolated intact mitochondria, p -coumaric acid inhibited respiration dependent on pyruvate oxidation but was ineffective on respiration driven by succinate and ,-hydroxybutyrate. It can be concluded that inhibition of pyruvate transport into the mitochondria is the most prominent primary effect of p -coumaric acid and also the main cause for gluconeogenesis inhibition. The existence of additional actions of p -coumaric acid, such as enzyme inhibitions and interference with regulatory mechanisms, cannot be excluded. © 2006 Wiley Periodicals, Inc. J Biochem Mol Toxicol 20:18,26, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20114 [source] Drinks of the Father: Father's Maximum Number of Drinks Consumed Predicts Externalizing Disorders, Substance Use, and Substance Use Disorders in Preadolescent and Adolescent OffspringALCOHOLISM, Issue 12 2002Stephen M. Malone Background The maximum number of drinks consumed in 24 hr seems to be an interesting phenotype related to alcoholism. The goal of the present study was to determine in an epidemiologic sample whether this measure of drinking history in fathers predicted externalizing behavioral disorders, substance use, and substance abuse in preadolescent and adolescent offspring and whether any such associations would be independent of paternal alcohol dependence diagnoses. Methods Subjects were male and female twins from both age cohorts of the Minnesota Twin Family Study, a population-based longitudinal study, and were approximately 11 or 17 years of age, respectively, upon study enrollment. In both age cohorts, diagnoses of conduct disorder, oppositional defiant disorder, and attention-deficit/hyperactivity disorder served as outcome measures. In addition, measures of lifetime substance use and of the presence of symptoms of substance abuse were derived for the 11-year-old cohort when subjects were approximately 14 years old and diagnoses of substance abuse were derived for the older cohort at age 17. An extension of logistic regression using generalized estimating equations served to assess whether paternal maximum alcohol consumption predicted filial outcome measures. Results Paternal maximum alcohol consumption was consistently associated with conduct disorder, substance use, and substance abuse or dependence in male and female offspring. These associations were not mediated by a primary effect of paternal alcoholism. Conclusions Paternal maximum alcohol consumption was uniquely associated with those offspring characteristics most reliably found in adolescent children of alcoholic parents. This phenotype might supplement DSM diagnoses of alcohol dependence to reduce the number of false positives in genetic research. [source] The behavioural ecology of the island fox (Urocyon littoralis)JOURNAL OF ZOOLOGY, Issue 1 2001Gary W. Roemer Abstract Insular populations typically occur at higher densities, have higher survivorship, reduced fecundity, decreased dispersal, and reduced aggression compared to their mainland counterparts. Insularity may also affect mating system and genetic population structure. However, these factors have not been examined simultaneously in any island vertebrate. Here we report on the ecological, behavioural and genetic characteristics of a small carnivore, the island fox Urocyon littoralis, from Fraser Point, Santa Cruz Island, California. Dispersal distances in island foxes are very low (mean 1.39 km, sd 1.26, range 0.16,3.58 km, n=8). Home-range size is one of the smallest (mean annual home range=0.55 km2, sd 0.2, n= 14) and density is nearly the highest recorded for any canid species (2.4,15.9 foxes/km2). Similar to other fox species, island foxes are distributed as mated pairs that maintain discrete territories. Overlap among mated pairs was always high (mean 0.85, sd 0.05), while overlap among neighbours (mean 0.11, sd 0.13), regardless of sex, was low. Despite this high degree of territoriality, island foxes are not strictly monogamous. Four of 16 offspring whose parents were identified by paternity analysis were a result of extra-pair fertilizations. Mated pairs were unrelated, however, suggesting inbreeding avoidance. Substantial population differentiation was found between the Fraser Point subpopulation and one only 13 km away (Fst= 0.11). We suggest that the primary effect of finite island area is to limit dispersal, which then influences the demography, behaviour and genetic structure of island fox populations. [source] Neurite growth in 3D collagen gels with gradients of mechanical propertiesBIOTECHNOLOGY & BIOENGINEERING, Issue 2 2009Harini G. Sundararaghavan Abstract We have designed and developed a microfluidic system to study the response of cells to controlled gradients of mechanical stiffness in 3D collagen gels. An ,H'-shaped, source,sink network was filled with a type I collagen solution, which self-assembled into a fibrillar gel. A 1D gradient of genipin,a natural crosslinker that also causes collagen to fluoresce upon crosslinking,was generated in the cross-channel through the 3D collagen gel to create a gradient of crosslinks and stiffness. The gradient of stiffness was observed via fluorescence. A separate, underlying channel in the microfluidic construct allowed the introduction of cells into the gradient. Neurites from chick dorsal root ganglia explants grew significantly longer down the gradient of stiffness than up the gradient and than in control gels not treated with genipin. No changes in cell adhesion, collagen fiber size, or density were observed following crosslinking with genipin, indicating that the primary effect of genipin was on the mechanical properties of the gel. These results demonstrate that (1) the microfluidic system can be used to study durotactic behavior of cells and (2) neurite growth can be directed and enhanced by a gradient of mechanical properties, with the goal of incorporating mechanical gradients into nerve and spinal cord regenerative therapies. Biotechnol. Bioeng. 2009;102: 632,643. © 2008 Wiley Periodicals, Inc. [source] 3231: The effect of riboflavin mediated corneal crosslinking on corneal hydrationACTA OPHTHALMOLOGICA, Issue 2010G KONTADAKIS Purpose To evaluate the primary effect of corneal collagen crosslinking on corneal hydration. Methods Twenty corneal buttons from freshly enucleated porcine eyes where immersed in riboflavin 0.1% in dextran 20% dilution for three hours in order for their hydration to reach an equilibrium. Corneal buttons where divided in two groups; the first group was stored in dark conditions while the other group was irradiated with UV radiation (390nm) for 30 minutes to stimulate collagen cross-linking according to the clinically applied protocol. After irradiation all corneas were immersed in dextran 20% solution for 30 additional minutes and subsequently weighted. Finally all corneal buttons were dehydrated for 48 hours in a desiccating oven set at 62Co and weighted again to obtain their dry mass. Hydration (%) of each button was calculated. Results were analyzed with non parametric tests. Results Irradiated group of corneas had statistically significant lower hydration than the non irradiated group. (p<0.05, Mann-Whitney Test). Mean hydration in the irradiated group was 71% and in the non-irradiated 75%. Conclusion Collagen crosslinking causes corneal dehydration that can be detected immediately after the procedure. This phenomenon may contribute to increased mechanical stiffness of the cornea. [source] | |||||||||||||