bluuebunny/crossref_metadata_2025 huggingface dataset:
Restoring Savanna Using Fire: Impact on the Breeding Bird Community
Authors: Davis Mark A. , Peterson David W. , Reich Peter B. , Crozier Michelle , Query Toby , Mitchell Eliot , Huntington Josh , Bazakas Paul
Published: March 2003

Restoration of many terrestrial plant communities involves the reintroduction of fire. However, there have been few studies of the effects of fire on the avifauna during the restoration process. To study the effects of oak savanna restoration on avian communities, breeding birds were censused and the vegetation structure documented in seven experimental burn units (8–18 ha) that had experienced different frequencies of controlled burns during the past 31 years (0–26 burns). Data were analyzed with both direct and indirect gradient analyses using multivariate techniques. The results showed that, as savanna restoration proceeded, there was a general decline in predominantly insectivorous species, particularly those that feed in the upper canopy region (leaves and air space), and a general increase in omnivorous species, particularly those that feed on the ground and in the lower canopy. Insectivorous bark gleaners (woodpeckers) also increased during restoration and were correlated with the increase in standing dead trees resulting from the fires. Overall, savanna restoration resulted in increases in the abundance of many open country bird species, including many species that have been declining in central and eastern North America, including red‐headed woodpecker, Baltimore oriole, eastern kingbird, vesper sparrow, field sparrow, lark sparrow, brown thrasher, American goldfinch, and brown‐headed cowbird. The shifts in species and guilds were correlated with changes in burn frequency and the macro vegetation structure—tree and shrub density, leaf area index, and relative proportion of standing dead trees. The findings show that savanna restoration can increase bird diversity and provide important habitat for uncommon or declining bird species. These birds are most likely attracted to one or more of the distinctive habitat features of the restored savanna environments, including scattered mature trees, standing dead trees and snags, and presence of both shrubby and grassland vegetation. The findings also suggest that restoration ecologists and wildlife biologists will need to work together to achieve desired goals, since different types of savanna restoration efforts may produce different effects on the breeding bird community.
Restoring the Vegetation of Mined Peatlands in the Southern Rocky Mountains of Colorado, U.S.A.
Authors: Cooper David J. , MacDonald Lee H.
Published: March 2003

South Park is a high‐elevation, semi‐arid, treeless intermountain basin in central Colorado. A few extreme rich fens occur on the western margin and in the center of South Park where regional and local groundwater flow systems discharge to the ground surface. Over the past 40 years there has been extensive peat mining in these fens, but restoration methods have yet to be developed and successfully applied. The first part of this study compared the naturally reestablished vegetation on six mined peatlands with six pristine sites, while the second part of the study tested different revegetation techniques in 27 plots with varying depths to the water table. The six mined sites had only 30 plant species as compared with 122 species in the unmined sites; 43% of the species in the mined sites were not present in the undisturbed fens. Even after 40 years the sedges and willows that dominate the undisturbed sites were largely absent on the mined sites. The revegetation experiments seeded eight species, transplanted Carex aquatilis (water sedge) seedlings, transplanted rhizomes from six species, and transplanted four species of willow cuttings. Of the eight species seeded, only Triglochin maritima (arrowgrass) germinated and established seedlings. C. aquatilis seedlings, rhizome transplants of C. aquatilis, Kobresia simpliciuscula (elk sedge), and Juncus arcticus (arctic rush), and willow cuttings all had differing patterns of survival with respect to the annual maximum height of the water table. These results indicate that the dominant species can be successfully reintroduced to mined surfaces with the appropriate hydrologic conditions, but human intervention will be necessary to rapidly re‐establish these species. The slow rate of peat accumulation means that restoration of the mined fens will require hundreds, if not thousands, of years.
The Influence of Rewetting on Vegetation Development and Decomposition in a Degraded Fen
Authors: Richert Maja , Dietrich Ottfried , Koppisch Dorothea , Roth Siegfried
Published: March 2003

The rewetting technique border irrigation was installed in a degraded fen peatland in northeastern Germany. Because of the prevailing site conditions, the technique resulted in two different rewetting variants (surface irrigation and temporary inundation) at the study site. This paper reports on the practicability of this technique and the influence of rewetting on vegetation development, decomposition processes and soil nutrient availability, and the possibilities for renewed peat accumulation. The technique proved to be suited for rewetting fen sites with a continuous slope, deep peat layer with low hydraulic conductivity, and upstream water recharge facilities. A subsidence of the ground‐water levels during the summer months, however, could not be avoided in dry years. The vegetation changed slowly from species‐poor grassland into typical fen plant communities, despite rewetting and soil tillage. Species richness, however, was higher in the surface irrigation than in the temporary inundation variant. A sufficient water supply proved to be absolutely necessary to retard decomposition processes because higher decomposition of root materials (i.e., higher k values) occurred under temporary inundated conditions. Generally, the higher water content in the soil after rewetting led to a lower nitrate‐N–to–ammonium‐N ratio in the topsoil in both rewetting variants. In the surface irrigation variant the mineral nitrogen content (Nmin) of the topsoil decreased from 7.8 to 4.4 g N/m2, which is also correlated with the increase in water content of the soil. The low Nmin levels of fens which were never deeply drained (0.9–2.8 g N/m2), however, were not reached within the observation period of 3 years.
Revegetation of Roadcut Slopes in Mesa Verde National Park, U.S.A.
Authors: Paschke Mark W. , DeLeo Claire , Redente Edward F.
Published: March 2003

The geology of Mesa Verde National Park (MVNP) poses unique problems to road construction and maintenance. Major geologic formations of the Park consist of an overlying resistant sandstone cap underlain by highly erodable shales. Once this sandstone cap is removed, the shales are easily eroded away, creating the notable mesas of the region. In many places, road construction has removed the sandstone layer and vegetation resulting in unaesthetic barren slopes that require continual maintenance and have proven difficult to revegetate. An experiment was conducted to evaluate the effectiveness of several cultural techniques combined with seeding and transplanting indigenous plants for revegetation of these roadcut slopes. Techniques evaluated were fertilization, mulching, soil pitting, and polyacrylamide amendments. Replicated test plots were established at three roadcut sites in MVNP to evaluate these techniques by measuring percent plant cover by species over a 4‐year period. A combination of seeding grasses and transplanting forbs and shrubs appeared to be the optimal way to maintain species diversity and structure on the roadcuts while accomplishing the goal of revegetating these difficult sites. The perennial forb Aster glaucodes and the shrub Artemisia ludoviciana showed high survival when transplanted in the experimental roadcut sites. These species, as well as the perennial grass Pascopyrum smithii, also established well from seed. The addition of an organic fertilizer, in combination with mulch, proved to be the most effective method of improving vegetation cover for these and other transplanted species.
Restoration of Wet Fen Meadows by Topsoil Removal: Vegetation Development and Germination Biology of Fen Species
Authors: Patzelt Annette , Wild Ulrich , Pfadenhauer Jörg
Published: March 2003

The present investigation was part of a fen restoration project, which deals with the rehabilitation of a deeply drained peat land used for intensive agriculture for more than 200 years. Consequently, the conditions for restoration are unfavorable. The hay of well‐developed fen meadows from nature reserves in the region appeared to contain enough viable seeds to act as a source for the development of target communities when spread out on bare peat after topsoil removal. Repeated vegetation analysis showed that a combination of topsoil removal and hay transfer resulted in the establishment of new populations in the target area for 70% of the species of the donor area. Germination conditions of fen species were investigated to determine the optimal combination for stimulating germination rates. Most fen species were found to be dormant, and it was shown that dormancy could be broken with fluctuating light and temperature cycles and stratification pre‐treatment.
Comparing the Importance of Seedbed and Canopy Type in the Restoration of Upland Thuja occidentalis Forests of Northeastern Minnesota
Authors: Cornett Meredith W. , Puettmann Klaus J. , Frelich Lee E. , Reich Peter B.
Published: March 2003

In cold‐temperate ecosystems of the upper Great Lakes Region, evergreen conifer‐dominated forests were once common. As a result of past management practices, early‐successional deciduous forests now dominate the landscape. Embedded in this matrix are stands of shade‐tolerant conifers, including Thuja occidentalis. For the past several decades, large‐scale T. occidentalis regeneration in remnant T. occidentalis and adjacent Betula papyrifera forests has not occurred. Using a combination of restoration experiments and field surveys at three study sites on the Lake Superior Highlands, Minnesota, U.S.A., we examined safe sites for T. occidentalis regeneration under both Thuja and Betula canopy types. This study focused on the colonization and establishment phases of regeneration, differentiating among safe‐site components for T. occidentalis. Seedbed type determined colonization success, with higher rates on conifer logs than on B. papyrifera logs, mounds, or pits. Mortality rates for seedlings on natural decayed wood seedbeds were higher under Thuja canopy than under Betula canopy, but the reverse was true for seedlings on manipulated seedbeds, suggesting that seedbed type was more important than the dominant canopy type. Growth rates for seedlings on moved log segments were greater under the Betula than the Thuja canopy type, but seedlings on natural decayed wood seedbeds did not exhibit this difference. Results indicated that T. occidentalis regeneration was more limited in Betula forest by seedbed availability, while in Thuja forest canopy conditions were more limiting.
Forest Development, Wood Jams, and Restoration of Floodplain Rivers in the Puget Lowland, Washington
Authors: Collins Brian D. , Montgomery David R.
Published: March 2003

Historically in Puget Lowland rivers, wood jams were integral to maintaining an anastomosing channel pattern and a dynamic channel–floodplain connection; they also created deep pools. In the late 1800s, wood was removed from most rivers, rivers were isolated from their floodplains, and riparian forests were cut down, limiting wood recruitment. An exception to this history is an 11‐km‐long reach of the Nisqually River, which has natural banks and channel pattern and a mature floodplain forest. We use field and archival data from the Nisqually River to explore questions relevant to restoring large rivers in the Pacific Northwest and other forested temperate regions. In particular, we focus on the relation between recovery of in‐channel wood accumulations and valley bottom forest conditions and explore implications for river restoration strategies. We find that restoring large rivers depends on establishing riparian forests that can provide wood large enough to function as key pieces in jams. Although the frequency of large trees in the Nisqually valley bottom in 2000 is comparable with that of 1873 land surveys, many formerly more abundant Thuja plicata (western red cedar) were cut down in the late 1800s, and now hardwoods, including Populus trichocarpa (black cottonwood) and Acer macrophyllum (bigleaf maple), are also abundant. Pseudotsuga menziesii (Douglas fir) and fast‐growing P. trichocarpa commonly form key pieces that stabilize jams, suggesting that reforested floodplains can develop naturally recruited wood jams within 50 to 100 years, faster than generally assumed. Based on the dynamic between riparian forests, wood recruitment, and wood jams in the Nisqually River, we propose a planning framework for restoring self‐sustaining dynamic river morphology and habitat to forested floodplain rivers.
Does Facilitation of Faunal Recruitment Benefit Ecosystem Restoration? An Experimental Study of Invertebrate Assemblages in Wetland Mesocosms
Authors: Brady Valerie J. , Cardinale Bradley J. , Gathman Joseph P. , Burton Thomas M.
Published: March 2003

We used wetland mesocosms (1) to experimentally assess whether inoculating a restored wetland site with vegetation/sediment plugs from a natural wetland would alter the development of invertebrate communities relative to unaided controls and (2) to determine if stocking of a poor invertebrate colonizer could further modify community development beyond that due to simple inoculation. After filling mesocosms with soil from a drained and cultivated former wetland and restoring comparable hydrology, mesocosms were randomly assigned to one of three treatments: control (a reference for unaided community development), inoculated (received three vegetation/sediment cores from a natural wetland), and stocked + inoculated (received three cores and were stocked with a poorly dispersing invertebrate group—gastropods). All mesocosms were placed 100 m from a natural wetland and allowed to colonize for 82 days. Facilitation of invertebrate colonization led to communities in inoculated and stocked + inoculated treatments that contrasted strongly with those in the unaided control treatment. Control mesocosms had the highest taxa richness but the lowest diversity due to high densities and dominance of Tanytarsini (Diptera: Chironomidae). Community structure in inoculated and stocked + inoculated mesocosms was more similar to that of a nearby natural wetland, with abundance more evenly distributed among taxa, leading to diversity that was higher than in the control treatment. Inoculated and stocked + inoculated communities were dominated by non‐aerial invertebrates, whereas control mesocosms were dominated by aerial invertebrates. These results suggest that facilitation of invertebrate recruitment does indeed alter invertebrate community development and that facilitation may lead to a more natural community structure in less time under conditions simulating wetland restoration.
Effects of Pre‐Planting Soaking on Growth and Survival of Black Willow Cuttings
Authors: Schaff Steven D. , Pezeshki S. Reza , Shields F. Douglas
Published: March 2003

Black willow (Salix nigra) uses periodic flood events for dispersal of vegetative propagules, subjecting them to periods of soaking before their deposition along the streambank. It was hypothesized that this life history trait results in optimal conditions for willow growth and survival. To test this hypothesis, a greenhouse experiment was conducted using 1.2‐m‐long black willow cuttings (posts) with a basal diameter of 5 cm. Cuttings were subjected to three soaking treatments (0, 3, and 10 days) and then grown under four soil moisture regimes (control, drought, permanently flooded, and intermittently flooded). Growth, biomass, and survival were recorded. Results showed that soaking posts for 10 days was most beneficial in the control soil moisture regime, enhancing root, shoot, leaf, and total biomass production. Shoot abundance and growth were also enhanced by 10 days of soaking in the control and permanently flooded moisture regimes. Finally, survival increased significantly in control and drought moisture regimes in response to the 10‐day soaking treatment. Results clearly demonstrated that soaking had significant effects on willow post success when evaluated across all soil moisture regimes. Posts subjected to the 10‐day soaking treatment consistently had greatest growth and biomass and displayed a doubling of the survival rate. Therefore, soaking willow cuttings before planting is a simple, inexpensive technique that may be used to bolster streambank restoration success.
Importance of Backyard Habitat in a Comprehensive Biodiversity Conservation Strategy: A Connectivity Analysis of Urban Green Spaces
Authors: Rudd Hillary , Vala Jamie , Schaefer Valentin
Published: March 2003

Connectivity has been an accepted goal in ecological restoration of wilderness areas for some time, but it is a relatively new approach in urban areas. The connectivity analysis presented here explores the numbers and patterns of corridors required to connect urban green spaces as part of an overall biodiversity conservation strategy. Green spaces in this study were weighted based on size and a habitat requirement of 0.5 ha for a hypothetical indicator species. Thirteen potential networks were evaluated using Gamma, Beta, and Cost Ratio indices. The study zone contained 54 green spaces (habitat nodes) with a combined area of 636.5 ha in a total urban area of approximately 2,600 ha. Several models (Travelling Salesman, Paul Revere, and Least Cost to User) were used to evaluate possible connections. These results indicated that at least 325 linkages are necessary to connect half of the nodes. Such large numbers of linkages are only feasible by enhancing the matrix of backyard habitat, planted boulevards, and utility rights‐of way found in a city. Strengthening such networks should work well to support the biota protected in urban parks and wildlife refuges and the seasonal migrants that sometimes depend on urban habitats for their survival.
Seedling Survival from Locally and Commercially Obtained Seeds on Two Semiarid Sites
Authors: Humphrey L. David , Schupp Eugene W.
Published: March 2003

Local populations of plants are likely to be better adapted to a site than populations from elsewhere. Thus, local seeds should yield higher survival in restoration attempts than commercial seed stocks. We compared seedling survival from locally and commercially obtained seeds of seven species, Pseudoroegneria spicata (bluebunch wheatgrass), Elymus elymoides (squirreltail), Pascopyrum smithii (western wheatgrass), Stipa hymenoides (Indian ricegrass), Stipa comata (needle‐and‐thread), Chrysothamnus nauseosus (rubber rabbitbrush) and Ephedra nevadensis (Mormon tea) over three years on two sites in Utah (Dugway and Tintic) that were dominated by the introduced annual Bromus tectorum (cheatgrass). At the Dugway site we included burned and unburned seedbed treatments. For all species at Dugway, seedling survival to the first summer was higher on burned plots where B. tectorum densities were greatly reduced. First‐year seedling survival was 20–30% for most species on the Dugway burned plots and at Tintic. At the drier Dugway site, only S. hymenoides and Ephedra had substantial third‐year survival. Elymus and Pascopyrum survived to the third year only at the moister Tintic site. Survival to the third year was less than 3% for all species except S. comata (6% survival), and densities were low (0.2–1.0 plants/m2). However, third‐year plants were well established and the grasses flowered. Pseudoroegneria and Ephedra at Dugway (on burned plots) and S. comata and Elymus at Tintic had higher first‐year survival or higher survival based on survival curves from local than from commercial seeds. However, final survival was never significantly higher, although such a trend was suggested. Seed dormancy traits could also provide advantages to local populations, and we observed differences in dormancy between local and commercial S. comata and S. hymenoides seeds that may be an example.
Restoring Structure in Late‐Successional Sagebrush Communities by Thinning with Tebuthiuron
Authors: Olson Richard A. , Whitson Thomas D.
Published: March 2003

Late successional, dense Artemisia tridentata (big sagebrush) stands restrict associated plant species production, resulting in a monotypic, shrub‐dominated community that threatens biodiversity preservation and ecosystem function. Traditional practices to control A. tridentata can severely reduce or temporarily eliminate A. tridentata and other plant species. Thinning A. tridentata with low rates of the herbicide tebuthiuron enhances herbaceous plant production, community structure, ecosystem functioning, and biodiversity. Tebuthiuron was applied at rates of 0.11–1.0 kg ai/ha to A. tridentata‐dominated plots at Ten Sleep (1979), Lander (1993), and Waltman (1993), Wyoming. Changes in A. tridentata canopy cover, associated plant species biomass, and community composition were evaluated 13 and 14 years post‐treatment at Ten Sleep, and 2 and 4 years post‐treatment at Lander and Waltman. At all sites A. tridentata canopy cover decreased proportionally with increased tebuthiuron rate. Biomass of grasses increased as shrub biomass and cover decreased with increasing tebuthiuron rate. Forb biomass varied between treatments across sample year and site. Shifts from shrub‐dominated control to grass‐dominated treatment plots were attributable to biomass differences of A. tridentata and 2–3 grass species among treatments. The number of plant species was not significantly different between treatments at any site. Similarity indexes revealed progressively greater dissimilar plant composition between the control and sequential treatment plots of increased tebuthiuron rate. Incremental rates of tebuthiuron produce gradual changes in plant species composition without reducing species richness, which may have utility in certain restoration projects.
Genetic Refinement And Physical Mapping Of The CMT4B Gene On Chromosome 11Q22
Authors: Bolino A. , Levy E.R. , Muglia M. , Conforti F.L. , LeGuern E. , Salih M.A.M. , Georgiou D.M. , Hausmanowa‐Petrusewicz I. , Mandich P. , Gambardella A. , Quattrone A. , Devoto M. , Monaco A.P.
Published: March 2003

Charcot‐Marie‐Tooth disease type 4B (CMT4B) is a demyelinating autosomal recessive motor and sensory neuropathy characterized by focally folded myelin sheaths in the peripheral nerve. We recently mapped the CMT4B gene to a 5‐cM interval on chromosome 11q22, using homozygosity mapping and haplotype sharing analysis on a large inbred pedigree. In the present study, we report the construction of a YAC‐based transcript map across the 5‐cM critical region, including 26 YACs, 35 STSs, and 52 ESTs. Furthermore, using 15 additional physically ordered microsatellite markers from the 11q22 region on the original inbred family, we were able to narrow the critical interval for the gene to 2 Mb, which is now flanked by markers D11S1757 and CHLC‐GATA3B05. Finally, after computer analysis of the 33 ESTs assigned to the 2‐Mb interval, we demonstrated that 21 different transcripts as well as 3 known genes might represent potential candidates for the disease.
Evaluation Of Diabetic Neuropathy Through The Quantitation Of Cutaneous Nerves
Authors: Hirai A. , Yasuda H. , Joko M. , Maeda T. , Kikkawa R.
Published: March 2003

The significance and usefulness of immunohistochemically quantitated cutaneous nerves in the evaluation of diabetic neuropathy was examined in biopsied skins of the calf from healthy subjects (n = 12) and non‐insulin dependent diabetic patients (n = 32) with diabetic sensory neuropathy. Skin samples were immunostained with antibodies against protein gene product (PGP) 9.5, a pan‐axonal marker. A quantitative analysis to determine nerve fiber (NF) number and nerve lengths (NLs) was performed on nerve fibers of the epidermis and the dermis and on nerves surrounding sweat glands. Nerve function tests were performed on the biopsied sites and erythrocyte aldose reductase level was determined by enzyme‐linked immunosorbent assay. Numbers of epidermal NFs, NLs of epidermis and dermis and NL around sweat glands were significantly decreased in diabetic patients compared with control subjects (P<0.001, P<0.001, P < 0.01, P < 0.01, respectively). NL of epidermis showed a significant correlation with NL of dermis (P < 0.01). Sural nerve conduction velocity was significantly correlated with NL of dermis (P < 0.05). Patients with higher AR level (> 10.8 (average in 555 diabetic patients) ng/mgHb) possessed a shorter NL of dermis NFs than those with lower AR level (> 10.8) (P < 0.05). These findings suggest that the quantitation of cutaneous nerves in biopsied skin samples provides important information about diabetic neuropathy and may improve the understanding of the pathophysiology of sensory nerve terminals in diabetic neuropathy.
Upregulation And Interaction Of TNFα and Gelatinases A and B In Painful Peripheral Nerve Injury
Authors: Shubayev V.I. , Myers R.R.
Published: March 2003

Chronic constriction injury (CCI) to peripheral nerve causes a painful neuropathy in association with a process of axonal degeneration and endoneurial remodeling that involves macrophage recruitment and local increase in extracellular proteases and tumor necrosis factor alpha (TNF‐α). Cell surface activation of TNF‐α from its transmembrane precursor, as well as sequestration of TNF‐α receptors II and I, is performed by the zinc‐dependent endopeptidase family of matrix metalloproteinases (MMPs). Among TNF‐α‐converting MMPs, basal lamina degrading gelatinases are thought to play a role in sciatic nerve injury. In the present study, we determined the forms of TNF‐α involved in the development of CCI neuropathy in rats, using Western blot analysis, and the temporal correlation of TNF‐α and TNFRI protein profiles with gelatinase activity at the site of peripheral nerve injury. We observed two peaks in TNF‐α protein during the first week of CCI that correspond to previously reported peaks in painful behavior. We propose that the first peak at 6 h post‐CCI is due to the local expression of the cytotoxic transmembrane 26 kDa TNF‐α protein released by resident Schwann cells, mast cells and macrophages. This peak in TNF‐α protein expression corresponds to an increase in gelatinase B (MMP‐9) activity, which is greatly upregulated as early as 3 h following CCI to rat sciatic nerve. The second peak occurs at 5 days post‐CCI, and may represent TNF‐α protein released by hematogenously recruited macrophages. This peak is marked by the increase in active soluble 17 kDa TNF‐α and by gelatinase A (MMP‐2) upregulation. These observations suggest that there is a pathogenic role for the TNF‐α‐converting function of MMP‐2 in painful CCI neuropathy. We conclude that severe nerve injury induces MMPs, TNF‐α and TNFRI, which interactively control the privileged endoneurial environment and the pathogenesis of the painful neuropathies associated with the macrophage‐dependent processes of Wallerian degeneration.
Evaluation Of Direct And Axon Reflex Sweating In The Mouse
Authors: Vilches J.J. , Navarro X.
Published: March 2003

The nicotinic axon reflex‐mediated sudomotor response was studied in mice and rats by recording the impressions of sweat droplets made in silicone molds after local injection of nicotine, and compared with sweating induced by acetylcholine and pilocarpine. Nicotine failed to activate mouse plantar sweat glands at any of the concentrations used (from 3 × 10−6 to 3 × 10−1 M). On the contrary, both acetylcholine and pilocarpine produced a dose‐dependent increase in the number of secreting sweat glands. The location of sweat glands reactive to pilocarpine and acetylcholine was similar and restricted to the pads near the site of injection. We conclude that the sudomotor axon reflex response mediated by nicotinic receptors is not present in the mouse and the rat.
Cholecystokinin‐8 Enhances Nerve Growth Factor Synthesis And Promotes Recovery Of Capsaicin‐Induced Sensory Deficit
Authors: Manni L. , Lundeberg T. , Tirassa P. , Aloe L.
Published: March 2003

1. Alterations of nerve growth factor (NGF) expression have been demonstrated during peripheral nerve disease and the impaired expression or synthesis and transportation of NGF has been correlated with the pathogenesis of several peripheral neuropathies. Since exogenous NGF administration seems to cause undesired side‐effects, therapeutical strategies based on the regulation of endogenous synthesis of NGF could prove useful in the clinical treatment of these disorders. 2. The aim of the present study was to analyse the effects of exogenous peripheral administration of the neuropeptide cholecystokinin‐8 (CCK‐8) on endogenous NGF synthesis, NGF mRNA and distribution of peripheral neuropeptides which are known to be regulated by this neurotrophin. 3. To address these questions we studied the effects of capsaicin (CAPS) before and after the administration of CCK‐8 on NGF levels. NGF mRNA expression and localization, and the concentration of substance P (SP) and calcitonin gene‐related peptide (CGRP) in peripheral tissue. 4. These studies demonstrate that administration of the CCK‐8 induces an increase of NGF protein and mRNA in peripheral tissue. NGF level in paw skin of CAPS/CCK‐8‐treated mice is 3 fold higher than in controls (1241 +/− 110 pg/ gr of tissue wet weight versus 414 +/− 110 pg /gr of controls) and nearly 6 fold higher than in CAPS‐treated mice (1241 +/− 110 pg/ gr versus 248 +/− 27 pg/ gr). The increase of NGF is correlated with the recovery of impaired nocifensive behaviour and with an overexpression of SP and CGRP. 5. The evidence that CCK‐8 promotes the recovery of sensory deficits suggests a potential clinical use for this neuropeptide in peripheral neuropathies.
Relationships Between Hydrophobicity, Reactivity, Accumulation And Peripheral Nerve Toxicity Of A Series Of Platinum Drugs
Authors: Screnci D. , McKeage M.J. , Galettis P. , Hambley T.W. , Palmer B.D. , Baguley B.C.
Published: March 2003

Previous work has shown platinum drugs to differ in their effects on the peripheral nervous system. To test whether their differential toxicity was due to differences in their partitioning into the peripheral nervous system, we correlated the hydrophobicity, reactivity, tissue accumulation and neurotoxicity of a series of eight platinum analogues. Neurotoxicity was detected by measuring sensory nerve conduction velocity (SNCV) in Wistar rats treated twice per week at the maximum tolerated dose. Tissue platinum concentrations were measured by inductively coupled plasma mass spectrometry. Hydrophobicity (log P) was measured using an octanol‐aqueous shake‐flask method. The half‐life of platinum drug binding to plasma proteins in vitro was determined. The cumulative dose causing altered SNCV ranged from 15 to > 2050 micromol kg(‐1). Ranking of the compounds by their neurotoxic potency in rats (oxaliplatin > R,R‐(DACH)PtC4 > ormaplatin > S,S‐ (DACH)PtCl4 > S,S‐(DACH)Pt oxalato > cisplatin > carboplatin > JM216) correlated with the frequency of neurotoxicity in patients (r > 0.99, P < 0.05). Ranking the compounds by their peripheral nerve accumulation was cisplatin > carboplatin > oxaliplatin > R,R‐(DACH)PtCl4 approximate to S,S‐(DACH)PtCl4 and did not correlate with neurotoxicity. Log P ranged from −2.53 to −0.16 but did not correlate with neurotoxicity. Log P correlated inversely with platinum accumulation in dorsal root ganglia (r2 = 0.99, P = 0.04), sural nerve (r2 = 0.85, P = 0.025), sciatic nerve (r2 = 0.98, P = 0.0012), spinal cord (r2 = 0.97, P = 0.018) and brain (r2 = 0.98, P = 0.001). Reactivity correlated with neurotoxicity potency in rats (r2 = 0.89, P = 0.0005) and with the frequency of neurotoxicity in patients (r2 = 0.99, P = 0.0002). The hydrophilicity of platinum drugs correlates with platinum sequestration in the peripheral nervous system but not with neurotoxicity. Differences in the reactivity of platinum complexes accounts for some of the variation in their neurotoxicity.
Epidemiology and clinical features of HIV‐1 associated neuropathies
Authors: Verma Ashok
Published: March 2003

Abstract  Peripheral neuropathy is common in human immunodeficiency virus type‐1 (HIV‐1) infection. Peripheral neuropathies complicate all stages of the HIV‐1 disease and cause considerable morbidity and disability in HIV‐1 infected individuals and acquired immunodeficiency syndrome (AIDS) patients. Whereas symptomatic neuropathies occur in approximately 10% to 15% of HIV‐1‐infected patients overall, pathologic evidence of peripheral nerve involvement is present in virtually all end‐stage AIDS patients. There are 6 major clinical types of HIV‐associated neuropathies that are regularly seen in large HIV‐1 clinics. Distal sensory polyneuropathy (DSP) is the most common among the HIV‐1‐associated neuropathies. DSP generally occurs in later stages of HIV‐1 infection and it follows an indolent and protracted clinical course. The dominant clinical features in DSP include distal pain, paresthesia and numbness in a typical length‐dependent fashion with proximal to distal gradient. Whereas toxic neuropathies—secondary to certain antiretroviral agents—are clinically similar to DSP, their temporal relation to neurotoxic medication helps distinguish them from other HIV‐1‐associated neuropathies. DSP and toxic neuropathy may coexist in a single patient. Acute and chronic inflammatory demyelinating polyradiculoneuropathies (AIDP and CIDP) produce global limb weakness. AIDP may occur at seroconversion and it can therefore be the initial manifestation of HIV‐1 infection. CIDP generally occurs in the mid to late stages of HIV‐1 infection. Progressive polyradiculopathy (PP) occurs in patients with advanced immunodeficiency and is generally caused by the opportunist cytomegalovirus (CMV) infection. Mononeuropathy multiplex (MM) in early stages of HIV‐1 infection is immune mediated, whereas in advanced AIDS it is caused by the CMV infection. Finally, subclinical autonomic nervous system involvement is common in all stages of HIV‐1 infection. Because HIV‐1‐associated neuropathies are diverse in their etiology and pathogenesis, a precise clinical diagnosis is required to formulate a rational therapeutic intervention.
A double‐blind placebo‐controlled clinical trial of recombinant human brain‐derived neurotrophic factor (rhBDNF) in diabetic polyneuropathy
Authors: Wellmer Andreas , Misra Vijay Peter , Sharief Mohammad K. , Kopelman Peter G. , Anand Praveen
Published: March 2003

Abstract  A randomized, double‐blind, placebo‐controlled study of brain‐derived neurotrophic factor (rhBDNF) was conducted in 30 patients with insulin‐treated diabetes mellitus, with obligatory abnormalities of sural nerve conduction studies and vibration perception threshold (VPT) at the great toe on recruitment. Nine patients received placebo, 11 rhBDNF (25 μg/kg) and 10 rhBDNF (100 μg/kg) s.c. daily for 3 months, and were assessed at days 0, 8, 15, 29, 43, 57 and 85 with nerve conduction and quantitative sensory and autonomic tests including VPT, thermal and light touch thresholds, and cutaneous axon‐reflexes. No statistically significant differences were found among the 3 treatment groups between baseline and day 85 values. To examine possible reasons for lack of effect, post hoc analysis was performed. In the subset of patients with abnormal but detectable cool detection threshold (CDT) at baseline, there was improvement of CDT at day 85 when compared to baseline in the treated (p < 0.02) but not placebo group. Further, from days 43 to 85, in the treated group but not the placebo group, CDT was indistinguishable from a group of matched normal subjects (p> 0.05). Skin biopsies failed to show evidence of structural change; assessment of innervation of hair follicles, which is partly dependent on BDNF, was not possible because of the marked loss of this end‐organ in diabetic neuropathic skin. The only side effects of rhBDNF were infrequent non‐painful injection‐site skin reactions and increased gut motility at the higher dose. We conclude that further preclinical studies are warranted before any future clinical trials to see if rhBDNF improves CDT and constipation in diabetics.
Nerve Granulomas And Vasculitis In Sarcoid Peripheral Neuropathy ‐ A Clinicopathological Study Of 11 Patients
Authors: Said G , Lacroix C , Plante‐Bordeneuve V , Le Page L , Pico F , Presles O , Senant J , Remy P , Rondepierre P , Mallecourt J.
Published: March 2003

Peripheral neuropathy is a rare, yet treatable manifestation of sarcoidosis, a multisystem disorder characterized by the presence of non‐caseating granulomas that are seldom found in nerve biopsy specimens. In order to learn more about the subject, we reviewed our clinical and pathological findings in a series of 11 patients (six men and five women aged 26‐83 years) with symptomatic neuropathy associated with characteristic granulomas in nerve biopsy specimens. Only two patients were known to have sarcoidosis before the occurrence of the neuropathy. The neuropathy was focal or multifocal in six patients, including one with a multifocal neuropathy associated with conduction blocks, and one with a multifocal axonal motor deficit. Four patients had a distal symmetrical deficit and one patient had a Guillain‐Barré‐like syndrome with facial diplegia and respiratory failure. Serum angiotensin‐converting enzyme concentration was elevated in only two patients. Epineurial granulomas and perineuritis were present in all nerve specimens. The inflammatory infiltrates invaded the endoneurium, following connective tissue septae and blood vessels, in five patients. Multinucleated giant cells were found in eight patients and necrotizing vasculitis in seven. Inflammatory lesions were associated with variable, asymmetrical involvement of nerve fascicles and axon loss. A muscle specimen was sampled during the same procedure in 10 patients. It showed inflammatory infiltrates and granulomas in nine patients and necrotizing vasculitis in two. Immunolabeling showed a mixed inflammatory infiltrate of T cells (predominantly CD4+ cells) and macrophages, in keeping with a delayed hypersensitivity reaction. In addition to nerve involvement, all patients had at least one other tissue or organ affected, including muscle in nine patients, lungs and/or intrathoracic lymph nodes in eight, skin in three, arthritis in two, and peripheral lymph nodes, stomach and eye in one patient each. Most patients improved on corticosteroids. Two patients remain free of symptoms after 7 years. Severe side‐effects of long‐term treatment with corticosteroids occurred in two patients, leading to death in one. This study illustrates the wide range of clinical manifestations of sarcoid neuropathy and the frequent association of granulomatous inflammatory infiltrates with necrotizing vasculitis and with silent or symptomatic involvement of other organs.
REVEALING GENETIC DIVERSITY OF EUKARYOTIC MICROORGANISMS IN AQUATIC ENVIRONMENTS BY DENATURING GRADIENT GEL ELECTROPHORESIS
Authors: van Hannen Erik J. , van Agterveld Miranda P. , Gons Herman J. , Laanbroek Hendrikus J.
Published: March 2003

A new Eucarya‐specific 18S rDNA primer set was constructed and tested using denaturing gradient gel electrophoresis to analyze the genetic diversity of eukaryotic microorganisms in aquatic environments. All eukaryal lines of descent exhibited four or fewer nucleotide mismatches in the forward primer sequence, except for the Microspora line of descent. The reverse primer annealed to a more conserved region with fewer than two nucleotide mismatches. Genomic DNA from test organisms with different numbers of nucleotide mismatches were amplified to test primer specificity. Relatively low annealing temperatures allowed the amplification of sequences with up to four nucleotide mismatches while still maintaining specificity for the eukaryal domain. Denaturing gradient gel electrophoresis was used to separate similarly sized PCR products of environmental samples, and the obtained banding patterns were converted to a binary format for statistical comparisons. Cluster analysis of these patterns showed similar results to a cluster analysis based on environmental variables. This approach provides an analytical tool to study the population structure and molecular ecology of eukaryotic microbial communities inhabiting aquatic environments.
PATTERNS OF MACROALGAL SPECIES DIVERSITY IN DANISH ESTUARIES
Authors: Middelboe Anne Lise , Sand‐Jensen Kaj , Krause‐Jensen Dorte
Published: March 2003

We analyzed species number of macroalgae in relation to environmental variables at two spatial levels comprising 202 individual sites and 26 entire estuaries in Denmark. The species number of macroalgae increased with salinity and declined with nutrient concentrations both at the sites and in the estuaries. Availability of hard substratum was associated with higher species richness at the sites. The number of macroalgal species in the estuaries increased with higher mean depth and longer coastline, suggesting that both the vertical and horizontal extension of the colonization area are important for the maximum representation of macroalgal species. Mean depth explained as a single predictor 60% of the variability in species number in entire estuaries. Estuaries with high mean depth also tend to be large and have high salinity and transparent waters due to efficient exchange with open waters. In conclusion, we find that the regulation of species richness of macroalgae in Danish estuaries, though complex, is influenced predictably by salinity, water transparency, nutrient concentration, and availability of hard substrata.
IDENTIFICATION OF A CYCLIC AMP‐DEPENDENT PROTEIN KINASE IN THE DINOFLAGELLATE AMPHIDINIUM OPERCULATUM
Authors: Leighfield T.A. , Van Dolah F.M.
Published: March 2003

Cyclic AMP is an important signaling molecule in both prokaryotes and eukaryotes. In eukaryotes, the action of cyclic AMP is mediated by cyclic AMP‐dependent protein kinase (PKA). Efforts to identify PKA in dinoflagellates have met with mixed success in previous studies. In Amphidinium operculatum, we have identified the presence of cAMP, and observed cell cycle inhibition by the cAMP pathway inhibitor, isobutyl methylxanthine, suggesting the presence of a eukaryotic cAMP pathway. However, crude lysates of A. operculatum failed to show in vitro kinase activity toward kemptide, a specific substrate of mammalian PKA. This may reflect the presence of unidentified low molecular weight inhibitors, because when cell lysates were fractionated by gel filtration chromatography, cAMP dependent kinase activity was identified. The molecular weight of this PKA was 66 kDa, much smaller than bovine PKA (250 kDa), but similar to that reported in the diatom Cylindrotheca (78 kDa). Current work is focusing on characterization of subunit structure of the PKA of A. operculatum, as compared with bovine PKA.
MOLECULAR SYSTEMATIC ANALYSES INDICATE THAT THE ENIGMATIC APOPHLAEA IS A MEMBER OF THE HILDENBRANDIALES (RHODOPHYTA, FLORIDEOPHYCIDAE)
Authors: Saunders Gary W. , Bailey J. Craig
Published: March 2003

Nuclear small‐subunit (SSU) ribosomal DNA sequences were determined for Apophlaea lyallii Hooker f. et Harvey from New Zealand and an isolate of Hildenbrandia rubra (Sommerfelt) Meneghini from France. These data, in addition to SSU sequences representative of all the major florideophyte lineages, were used in molecular systematic investigations to confirm inclusion of Apophlaea in the Hildenbrandiales. Anatomical features that serve to unite Apophlaea and Hildenbrandia are discussed to buttress this result. Furthermore, our analyses support recognition of the Hildenbrandiales as sister to all other extant florideophyte lineages studied to date. An anomalous result positioning the SSU sequence generated herein for Hildenbrandia rubra closer to Apophlaea lyallii than to a previously published sequence for Hildenbrandia rubra requires further investigation.
GENETIC VARIATION AMONG STRAINS OF THE TOXIC DINOFLAGELLATE GYMNODINIUM CATENATUM (DINOPHYCEAE)
Authors: Bolch Christopher J. S. , Blackburn Susan I. , Hallegraeff Gustaaf M. , Vaillancourt René E.
Published: March 2003

The toxic dinoflagellate Gymnodinium catenatum Graham has formed recurrent toxic blooms in southeastern Tasmanian waters since its discovery in the area in 1986. Current evidence suggests that this species might have been introduced to Tasmania prior to 1973, possibly in cargo vessel ballast water carried from populations in Japan or Spain, followed by recent dispersal to mainland Australia. To examine this hypothesis, cultured strains from G. catenatum populations in Australia, Spain, Portugal, and Japan were examined using allozymes and randomly amplified polymorphic DNA (RAPD). Allozyme screening detected very limited polymorphism and was not useful for population comparisons; however, Australian, Spanish, Portuguese, and Japanese strains showed considerable RAPD diversity, and all strains examined represented unique genotypes. Multidimensional scaling analysis (MDS) of RAPD genetic distances between strains showed clear separation of strains into three nonoverlapping regional clusters: Australia, Japan, and Spain/Portugal. Analysis of genetic distances between strains from the three regional populations indicated that Australian strains were almost equally related to both the Spanish/Portuguese population and the Japanese population. Analysis of molecular variance (AMOVA) found that genetic variation was partitioned mainly within populations (87%) compared to the variation between the regions (8%) and between populations within regions (5%). The potential source population for Tasmania’s introduced G. catenatum remains equivocal; however, strains from the recently discovered mainland Australian population (Port Lincoln, South Australia, 1996) clustered with Tasmanian strains, supporting the notion of a secondary relocation of Tasmanian G. catenatum populations to the mainland via a shipping vector. Geographic and temporal clustering of strains was evident among the Tasmanian strains, indicating that genetic exchange between neighboring estuaries is limited and that Tasmanian G. catenatum blooms are composed of localized, estuary‐bound subpopulations.
THE RELATIONSHIP BETWEEN PSEUDOSCOURFIELDIA MARINA AND PYCNOCOCCUS PROVASOLII (PRASINOPHYCEAE, CHLOROPHYTA): EVIDENCE FROM 18S rDNA SEQUENCE DATA
Authors: Fawley Marvin W. , Qin Mingbo , Yun Yue
Published: March 2003

18S rDNA sequences were obtained for the prasinophytes Pseudoscourfieldia marina (Throndsen) Manton and Pycnococcus provasolii Guillard. These sequences, along with those of additional prasinophytes and other green algae and land plants, were used for phylogenetic analyses by the neighbor‐joining, maximum parsimony, and quartet puzzling methods. Results indicate that Ps. marina and Py. provasolii are closely allied and that both should be included in the Pycnococcaceae. In addition, results of these sequence analyses and additional pigment analysis indicate that the organism previously identified as Ps. marina, isolate CCMP 717, is, in fact, a Nephroselmis sp. or is closely related to that genus.