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Notes: Abstract Interest in restoring native ecosystems is resulting in conversion of marginal agricultural lands to bottomland hardwood-dominated forests in the midwestern and midsouthern United States. Growing stock for these efforts typically consists of planted oak (Quercus spp.) and volunteer vegetation. Reports of mixed reforestation success and the lack of post-establishment tree growth data prompted this evaluation of vegetation characteristics of 5- to 7-year-old operational restorations in the Lower Cache River Watershed in southernmost Illinois, U.S.A. Fraxinus pennsylvanica (green ash), Acer negundo (box-elder), and Liquidambar styraciflua (sweetgum) together comprised 77% of all tree stems observed. Full stocking of overstory tree species can be expected to produce a closed canopy stand within 160 m of a forested edge, due primarily to the abundance of rapidly growing volunteer-origin trees. Planted oaks contributed minimally to total tree stocking but were present in sufficient numbers to eventually improve wildlife habitat, and therefore satisfied restoration objectives. Oak height was 23% greater when in the presence of a non-oak tree species. Herbaceous cover was dominated by Solidago gigantea (late goldenrod) and Juncus spp. (rushes). Solidago gigantea was associated with poor growth and low density of non-oak stems, whereas Juncus dudleyi (Dudley's rush) was associated with taller non-oak stems. These results suggest that the presence of volunteer-origin trees is crucial for the creation of full stand stocking that will result in rapid development of a closed canopy forest. Improved success of future reforestation efforts will require more intensive methods to establish adequate stocking beyond 160 m of a forest edge. Methods described here could be adapted for agricultural field to forest restorations in other regions to predict critical distances from volunteer seed sources within which supplemental planting would be unnecessary to meet tree stocking objectives.

Notes: Two independently derived, inbred strains of genetically epilepsy-prone rats (GEPRs) have been developed, the moderately epileptic GEPR-3 and the more severely epileptic GEPR-9. Seizures expressed by GEPRs model human generalized tonic/clonic seizures (GTCSs) and partial seizures secondarily generalized to tonic/clonic seizures. Several types of existing antiepileptic drugs have been tested in the GEPR model. Without exception, the seizure suppressing properties of these drugs occur both in GEPR-3 s and GEPR-9s. The differential responses of the two GEPR strains separate the antiepileptic drugs into three categories: (1) those effective in GTCSs and partial seizures; (2) those that are additionally effective in absence seizures; and (3) those effective in absence seizures but not in convulsive seizures. No known false positives have yet been detected in GEPR tests. In addition to the utility of the seizures expressed by GEPRs in drug development paradigms, these animals also have potential in the search for drugs that are specifically “antiseizure predisposition” rather than merely anticonvulsant. Heretofore, worldwide drug development efforts have emphasized the discovery of drugs that are anticonvulsant in nonepileptic animals. As might have been anticipated, these same drugs have proven to be anticonvulsant in epileptic subjects. Paradigms that would detect drugs with the capacity to correct the biological determinants of predisposition are in early stages of application. Kindling seizures provide a means to identify drugs that might be useful in correcting stimulus-induced seizure predisposition. The GEPR and other genetic models of the epilepsies provide models for developing treatments to correct genetically determined seizure predisposition. Emerging evidence supports the hypothesis that GEPRs model comorbidity between the epilepsies and affective disorders. Understanding the basis of this comorbidity has the potential to enable the development of treatments that reverse the underlying abnormalities of the coexisting disorders. Because human epilepsies and affective disorders are environmentally and genetically complex, the abnormalities of the GEPR probably will not account for all predispositions leading to this comorbidity.

Notes: Our group and others have previously reported enhancement of cutaneous wound healing following the transfection of tissue with plasmid vectors expressing the DNA for growth factors. In these experiments, growth factor treated animals were usually compared to animals treated with control plasmid vector. To achieve consistent transfection, high DNA plasmid load and repeated penetrations of the wound by needle or gene gun were required. In the current experiments, we assessed the effect of the plasmid load and repeated tissue penetrations on wound healing of excisional wounds in diabetic C57 mice. Animals received 5 mm excisional wounds, and were assigned to the following groups, no treatment, phosphate buffered saline solution injections, and plasmid vector injection with and without the keratinocyte growth factor-1 gene. Intradermal injections of 100μg plasmid were given adjacent to the wounds at days 1–5, 7 and 11. At day 9, wound closure was more advanced in keratinocyte growth factor-1 treated animals compared to those treated with control plasmid. But a detrimental effect of the DNA plasmid injection was evident from a comparison of the DNA control group versus the non-injected group. Therefore, the challenge for developing an effective system for the enhancement of wound healing lies in improving transfection efficiency.

Notes: Fraxinus pennsylvanica (green ash) is commonly used for reforestation of agricultural lowlands in the midwestern and eastern United States. We evaluated the effects of herbicide (untreated, glyphosate, and sulfometuron methyl) and tillage (tilled and no-till) on F. pennsylvanica success and composition of associated volunteer vegetation 3 years after the treatment applications and reforestation of a formerly cultivated field in southern Illinois. Tillage had no effect on F. pennsylvanica growth, whereas both herbicides increased all measures of tree performance. The response of associated native and non-native species cover was affected by an interaction between the herbicide and tillage treatments. In the presence of herbicide, cover of native species was greater in the no-till treatment, whereas non-native cover was higher in the tillage treatment. Both native and non-native cover were unaffected by tillage in the absence of herbicide, and there were no differences in cover among the herbicide treatments in the presence of tillage. Total diversity was higher in the tillage treatment than the no-till treatment, and diversity was lower in the sulfometuron methyl herbicide treatment than the control and glyphosate herbicide treatment. Lower diversity in the sulfometuron methyl treatment was attributed to greater cover of a native perennial grass, Andropogon virginicus (Broomsedge), which was inversely related to total diversity. We conclude that a single glyphosate herbicide application can enhance F. pennsylvanica growth and conserve associated species diversity in this system. Furthermore, species-specific responses of the associated vegetation should be included in management considerations, particularly if silvicultural treatments influence dominance and diversity in the establishing understory community during reforestation.

Notes: We study three corporate nonmarket strategies designed to influence the lobbying behavior of other special interest groups: (1) astroturf, in which the firm covertly subsidizes a group with similar views to lobby when it normally would not; (2) the bear hug, in which the firm overtly pays a group to alter its lobbying activities; and (3) self-regulation, in which the firm voluntarily limits the potential social harm from its activities. All three strategies reduce the informativeness of lobbying, and all reduce the payoff of the public decision-maker. We show that the decision-maker would benefit by requiring the public disclosure of funds spent on astroturf lobbying but that the availability of alternative influence strategies limits the impact of such a policy.

Notes: Acute cocaine can inhibit catecholamine biosynthesis by regulating the enzymatic activity of tyrosine hydroxylase via alterations in the phosphorylation state of the enzyme. The mechanisms underlying acute cocaine-dependent regulation of tyrosine hydroxylase phosphorylation have not been determined. In this study, 0, 15 or 30 mg/kg cocaine was administered intraperitoneally to rats and the phosphorylation state of tyrosine hydroxylase in the brain was examined using antibodies specific for the phosphorylated forms of serine-19, -31 and -40 in tyrosine hydroxylase. In the caudate and nucleus accumbens, cocaine dose-dependently decreased the levels of phosphorylated serine-19, -31 and -40. In the ventral tegmental area, the levels of phosphorylated serine-19, but not serine-31 and -40, were decreased by 15 and 30 mg/kg cocaine. In the amygdala, the levels of phosphorylated serine-19, but not serine-31 or -40, were decreased. The functional effects of these alterations in phosphorylation state were assessed by measuring tyrosine hydroxylase activity in vivo(accumulation of DOPA after administration of the decarboxylase inhibitor NSD-1015). Acute administration of 30 mg/kg cocaine significantly decreased l-DOPA production in caudate and accumbens but not in amygdala. These data suggest that the phosphorylation of serine-31 or -40, but not serine-19, is involved in the regulation of tyrosine hydroxylase activity by acute cocaine.

Notes: In subprimates, a single form of tyrosine hydroxylase (TH) is expressed, whereas two TH protein isoforms have been identified in monkeys and four isoforms have been demonstrated in humans. In order to establish the evolutionary pattern/emergence of these multiple TH isoforms, adrenal medullae from different mammalian species were analyzed by blot immunolabeling using pan-specific TH antibodies and antibodies specific to each of the four human TH isoforms. The expression of multiple TH isoforms was primate specific and restricted to anthropoids: only a single TH isoform was detected in adrenal medullae from several subprimate and prosimian species (six species from four families), while two TH isoforms were found in all of the anthropoid species studied. The presence of four TH isoforms could only be demonstrated in human specimens. Contrary to previous suggestions, only one TH protein isoform was found in rats and only four TH protein isoforms were found in humans.

Notes: Depolarizing stimuli increase catecholamine (CA) biosynthesis, tyrosine hydroxylase (TH) activity, and TH phosphorylation at Ser19, Ser31, and Ser40 in a Ca2+-dependent manner. However, the identities of the protein kinases that phosphorylate TH under depolarizing conditions are not known. Furthermore, although increases in Ser31 or Ser40 phosphorylation increase TH activity in vitro, the relative influence of phosphorylation at these sites on CA biosynthesis under depolarizing conditions is not known. We investigated the participation of extracellular signal-regulated protein kinase (ERK) and cAMP-dependent protein kinase (PKA) in elevated K+-stimulated TH phosphorylation in PC12 cells using an ERK pathway inhibitor, PD98059, and PKA-deficient PC12 cells (A126-B1). In the same paradigm, we measured CA biosynthesis. TH phosphorylation stoichiometry (PS) was determined by quantitative blot-immunolabeling using site- and phosphorylation state-specific antibodies. Treatment with elevated K+ (+ 58 mm) for 5 min increased TH PS at each site in a Ca2+-dependent manner. Pretreatment with PD98059 prevented elevated K+-stimulated increases in ERK phosphorylation and Ser31 PS. In A126-B1 cells, Ser40 PS was not significantly increased by forskolin, and elevated K+-stimulated Ser40 PS was three- to five-fold less than that in PC12 cells. In both cell lines, CA biosynthesis was increased 1.5-fold after treatment with elevated K+ and was prevented by pretreatment with PD98059. These results suggest that ERK phosphorylates TH at Ser31 and that PKA phosphorylates TH at Ser40 under depolarizing conditions. They also suggest that the increases in CA biosynthesis under depolarizing conditions are associated with the ERK-mediated increases in Ser31 PS.

Notes: Transcatheter embolization of congenital or acquired superfluous vascular structure has become routine procedures performed by interventional pediatric cardiologists. Embolization procedure is often part of a collaborative effort with cardiac surgeons to palliate complex congenital heart defect, such as in embolizing aortopulmonary collateral arteries in patient with single ventricle physiology. In other cases, the procedure is the definitive treatment as in embolizing coronary artery fistula. Pediatric cardiologists performing embolization procedures should be familiar with available technologies as well as understand the underlying cardiac anatomy and pathophysiology. This article provides a comprehensive review of presently available embolization agents and technologies. Some of the technologies are used only by interventional radiologists but may be useful to pediatric cardiologists. Specific clinical applications in pediatric cardiology are also discussed with summary of current literature. With continue advancement in transcatheter technology and operator expertise, all unwanted vascular communication should be amenable to transcatheter embolization. (J Interven Cardiol 2003;16:425–448)

Notes: The successful employment of embolization coils for transcatheter occlusion of the patent ductus arteriosus (PDA) has resulted in acceptance of transcatheter occlusion as the treatment of choice for small to medium-sized PDAs. The Duct-Occlud device was developed to further improve the technique by utilizing a controlled release mechanism and coil shape specifically designed for the geometly of the ductus arteriosus. Clinical studies have demonstrated excellent efficacy with low embolization rates and low incidences of complications. Newer modifications have been designed for occlusion of larger PDAs and subaortic ventricular septal defects, and preliminary clinical results have been promising. (J Interven Cardiol 2001;14:231–238)