bluuebunny/crossref_metadata_2025_split huggingface dataset:
NGF Amplifies Expression of NGF Receptor Messenger RNA in Forebrain Cholinergic Neurons of Rats
Authors: Cavicchioli L. , Flanigan T. P. , Vantini G. , Fusco M. , Polato P. , Toffano G. , Walsh F. S. , Leon A. 
Published: April 2006

AbstractIn order to study the ligand‐mediated regulation of NGF receptors in vivo, we assessed NGF receptor mRNA in the septal area of both neonatal and adult rats following intraventricular NGF administration. In neonatal rats NGF treatment, in comparison with cytochrome c, elicited a pronounced augmentation in the level of NGF receptor mRNA. A similar effect was also observed following continuous intraventricular NGF infusion in young adult rats. In addition, in this latter case, the increase in NGF receptor mRNA was associated with an increase in NGF receptor‐related immunoreactivity, most likely associated with the cholinergic neurons, in the septal area. These results show that NGF itself may regulate expression of NGF receptor mRNA and corresponding protein levels in forebrain cholinergic neurons and suggest that NGF effects in the CNS may be mediated by an up‐regulation of NGF receptors.
Immunoreactive Calcitonin Gene‐Related Peptide, Vasoactive Intestinal Polypeptide, and Somatostatin in Developing Chicken Spinal Cord Motoneurons
Authors: Villar Marcelo J. , Roa Michèle , Huchet Monique , Hökfelt Tomas , Changeux Jean‐Pierre , Fahrenkrug Jan , Brown John C. , Epstein Miles , Hersh Louis 
Published: April 2006

AbstractThe distribution of calcitonin gene‐related peptide (CGRP)‐, vasoactive intestinal polypeptide (VIP)‐, and somatostatin (SOM)‐like immunoreactivities (‐LI) in neurons of the spinal cord of developing chickens was characterized by use of the indirect immunofluorescence technique, and the findings related to a possible role for these peptides in the development of muscles and motor endplates.CGRP‐LI in presumptive motoneurons of the ventral horn was first observed at embryonic day 6. During the following days the number of CGRP‐immunoreactive (IR) cells increased reaching high numbers between days 12 and 18 of incubation, and thereafter decreasing in numbers until hatching. SOM‐LI was first observed on embryonic day 7, while VIP‐LI appeared on days 12–13. The number of SOM‐ and VIP‐IR cells was considerably lower than that observed for CGRP‐LI, but they also exhibited an initial increase followed by a decrease towards hatching. Intrathecal administration of colchicine increased the number of CGRP‐IR motoneurons at days 7 and 30 after hatching and of VIP‐IR ones at day 7, while at day 30 no expression of VIP‐LI was found. Colchicine treatment did not cause any significant change in the number of SOM‐IR motoneurons after hatching.The effect of VIP, SOM, and CGRP on cAMP accumulation in primary cultures of chick muscle cells was determined after labelling of the cells by (2‐3H) adenine and by radioimmunoassay. All three peptides stimulated the accumulation of cAMP. However, the development of the pharmacological response of each of the peptides followed a different time course during in vitro differentiation of the primary cultures. The response of CGRP was the latest to develop and did not significantly decrease after the maximal response had been reached around day 3.The data are discussed in terms of ‘trophic’ effects of these neuropeptides upon muscle and spinal cord differentiation and synaptogenesis.
Behaviour of Medial Rectus Motoneurons in the Alert Cat
Authors: de la Cruz R. R. , Escudero M. , Delgado‐Garcia J. M. 
Published: April 2006

AbstractThe activity of identified medial rectus motoneurons was recorded in alert cats during spontaneous and vestibular induced eye movements. Medial rectus motoneurons fired a burst of spikes slightly preceding adducting saccades and increased their discharge rate linearly with successive eye positions in the adducting direction. Conduction velocity (21.3–98.2 m/s), eye position sensitivity (ks, 7.1 ± 1.5 spikes/s°deg), and eye velocity sensitivity (rs, 1 ± 0.2 spikes/s°deg/s) during spontaneous eye movements, and time constants calculated from phase lead analysis (T0, 135 ± 36 ms) showed values similar to those described previously for cat abducens motoneurons. The firing rate during repeated fixation of the same eye position was affected significantly by the direction of the preceding saccade and by the animal's level of alertness. Eye velocity sensitivity was not significantly affected by changes in the animal's level of alertness. A weak negative relationship (coefficient of correlation = ‐0.56) was observed between eye velocity sensitivity (rv) and sinusoidal rotational frequency, with no change in eye position sensitivity (kv) with stimulus frequency. The subsequent changes in the time constant (Tv) calculated as Tv= rv/kv in relation to stimulus frequency suggests that the oculomotor system deviates from a (linear) first‐order model.
Immunocytochemical Localization of Glia‐Derived Nexin, Laminin and Fibronectin on the Surface or Extracellular Matrix of C6 Rat Glioma Cells, Astrocytes and Fibroblasts
Authors: Halfter W. , Reinhard E. , Liverani D. , Ortman R. , Monard D. 
Published: April 2006

AbstractThe expression and cellular distribution of glia‐derived nexin (GDN), laminin and fibronectin on C6 rat glioma cells, rat brain astrocytes and rat fibroblasts were investigated by immunoblotting and immunocytochemistry. Western blot analysis of C6 cell homogenates confirmed the specificities of the antibodies. Immunocytochemical staining of C6 cells, astrocytes and fibroblasts showed that laminin, fibronectin and GDN were abundant on the surface of glioma cells and astrocytes whereas on fibroblasts fibronectin was abundant though only traces of GDN and laminin could be detected. The light microscopy data were confirmed by ultrastructural studies showing that each antigen was present on the surface of the C6 rat glioma cells as numerous spots with slightly different distribution patterns for each of the antigens. In fibroblast cultures, the antigens were also localized in the extracellular matrix in the vicinity of the cells. Migrating fibroblasts but not migrating glioma cells or astrocytes deposit the matrix‐proteins onto the substratum leaving behind a track of GDN, laminin and fibronectin. When the cells were treated with heparin prior to antibody incubation, the GDN immunoreactivity completely disappeared, whereas the distribution and abundance of laminin and fibronectin was not affected. Our data show that GDN binds, possibly by a heparin‐like molecule, to the outer surface of cells or to the extracellular matrix and may protect cells and matrix proteins against proteolytic degradation.
The Drosophila Mutant tetanic Interacts with a Gene Complex Including the Structural Locus of K+ Channels and Shows Altered Dephosphorylation and Learning
Authors: Orgad S. , Llamazares S. , Dudai Y. , Ferrús A. 
Published: April 2006

AbstractThe tetanic (tta; X.‐52.6) mutation has been isolated on the basis of its sensitivity to extradoses of the normal Shaker gene complex (ShC) where the K+ channel la is encoded. The mutant shows up to threefold elevation of the membrane bound protein phosphatase type 1 (PP1) activity in body extracts, probably due to reduced levels of the PP1 specific inhibitor 2 (I‐2). By contrast, PP1 activity in the head is only half of the normal value. In addition, tta fails to perform normally in a negative reinforcement olfactory paradigm. The functional relationships between phosphorylation, K+ currents, phosphatase activity and modulation of synaptic activity during learning and memory are discussed in the light of their possible genetic links.
Differential Expression of bcl‐2 and bax mRNA in Axotomized Dorsal Root Ganglia of Young and Adult Rats
Authors: Gillardon Frank , Wickert Hannes , Zimmermann Manfred 
Published: April 2006

AbstractBcl‐2 and Bax have recently been identified as putative repressor and effector proteins respectively, in the cell death program of growth factor‐deprived haematopoietic cell lines. Overexpression of bcl‐2 in neuronal cell culture prevents apoptosis induced by removal of neurotrophic factors. In the present in vivo study the expression of bcl‐2 and bax mRNA has been investigated in dorsal root ganglia of young and adult rats using polymerase chain reaction. A high constitutive expression was observed for both genes in control ganglia. Unilateral transection of the sciatic nerve led to a dramatic decrease in bcl‐2 mRNA levels in ganglia of young animals within 5 days following nerve lesion and a partial recovery thereafter. In contrast, the decline in bcl‐2 mRNA was much less pronounced in axotomized ganglia of adults. The amount of bax transcripts did not change significantly in ganglia of both young and adult rats up to 20 days after nerve injury. The decrease in bcl‐2 expression in dorsal root ganglia may be part of the molecular mechanism leading to neuronal cell death after axotomy‐induced deprivation of neurotrophic factors. The age‐dependent decline in the ratio of bcl‐2 to bax gene products may explain the greater susceptibility of immature neurons to apoptosis.
A randomized study comparing an antireflux system with a direct ureteric anastomosis in patients with orthotopic ileal neobladders
Authors: SHAABAN ATALLAH A. , ABDEL‐LATIF MOHAMED , MOSBAH AHMED , GAD HOSSAM , ERAKY IBRAHIM , ALI‐EL‐DEIN BEDEIR , OSMAN YASSER , EL‐MEKRESH MOHSEN , IBRAHIM EL‐HOUSSEINY , EL‐KAPPANY HAMDY 
Published: April 2006

Authors from Egypt conducted a randomized prospective study into the benefit of an anti‐reflux system in patients with orthotopic ileal neobladders. They found that anti‐reflux procedures were associated with a higher incidence of anastomotic structures. An editorial comment accompanies this paper, and together the two manuscripts make for interesting reading.OBJECTIVETo assess the benefit of an antireflux system in patients with orthotopic ileal neobladders, as there is controversy about whether reflux prevention offers any advantages.PATIENTS AND METHODSWe conducted a randomized prospective study between January 2002 and March 2004, on 60 patients (53 men and seven women) with a mean (sd) age of 52.7 (7.3) years, who were candidates for orthotopic neobladders. Patients with comorbidities were excluded. Preoperative evaluation included intravenous urography (IVU), cystoscopic biopsy and radioisotope renography to evaluate the differential glomerular filtration rates (GFRs). Cases with normal kidneys and ureters, and with similar GFRs, were enrolled. Surgery comprised a standard radical cystectomy with pelvic lymphadenectomy. The ureters were randomized to either a direct anastomosis into a 5‐cm ileal chimney on one side, or to be implanted using the antireflux serous‐lined extramural tunnel on the contralateral side in the same patient. Regular follow‐up included IVU and renography every 6 months in cancer‐free patients.RESULTSThe mean (sd) follow‐up was 23 (9.6) months. There was prolonged urinary leak from a refluxing ureter in one patient that was treated with a temporary percutaneous nephrostomy. Symptomatic pelvic collections required tube drainage in six cases. Six ureters developed early anastomotic strictures (one direct and five antirefluxing), and were treated with endoscopic ureterotomy in three and open revision in three. Serum creatinine levels were normal in all patients throughout the observation period. GFRs were similar in the two groups. The mean GFRs before surgery and at 6, 12, 18, and 24 months after cystectomy were: 55.1, 50.7, 49.4, 52.2 and 53.9 mL/min for the direct side; and 56.1, 53, 52.4, 53.2 and 50.4 mL/min for renal units with antirefluxing implantation. There was a significant deterioration of the GFRs due to anastomotic strictures, from 48.6 (6.7) mL/min before surgery to 31.8 (15.9) mL/min after the revision (P = 0.01).CONCLUSIONSThe antireflux procedures were associated with a higher incidence of anastomotic strictures than the direct methods and there was a significant deterioration of renal function after obstruction. The long‐term follow‐up data are awaited.
The effects of human chorionic gonadotrophin on normal testicular tissue of rats: dose‐dependence and reversibility
Authors: KARAMAN IHSAN M. , KAYA CEVDET , OZTURK METIN , PIRINCCI NECIP , YIMAZGUMRUKCU GULISTAN , TUKEN MURAT 
Published: April 2006

OBJECTIVETo investigate the effect of human chorionic gonadotrophin (hCG) on rat testicular tissue, and its reversibility and dose dependence.MATERIALS AND METHODSMale Wistar rats were assigned to groups (10 rats/group) receiving 10, 30 or 50 IU/kg hCG subcutaneously once daily for 15 days; 10 controls received subcutaneous isotonic saline. At 1 and 3 months later, five rats in each group were killed and their testes removed. The testes were examined histologically to measure seminiferous tubular diameter and germinal membrane thickness.RESULTSAt 1 month after hCG administration, the mean germinal membrane thickness in the testicular tissues of the hCG‐treated rats was significantly less than in control rats, and was also significantly different between all of the hCG‐treated groups (P < 0.05). However, at 3 months after hCG administration, all histological variables were similar to those in control rats (P > 0.05), and the mean germinal membrane thickness at 3 months after hCG administration was larger than that at 1 month (P < 0.05). There were no significant differences in the mean seminiferous tubular diameter between hCG‐treated rats and control rats.CONCLUSIONhCG impairs seminiferous tubule histology in the ‘normal’ descended testes of rats. This effect was dose‐dependent, and the changes were reversed at 3 months after treatment. Thus, although hCG therapy might affect the seminiferous tubules of contralateral descended testes in cryptorchid boys, these effects might be reversible.
Tidal Marsh Restoration: Trends in Vegetation Change Using a Geographical Information System (GIS)
Authors: Barrett Nels E. , Niering William A. 
Published: April 2006

AbstractAdequately evaluating the success of coastal tidal marsh restoration has lagged behind the actual practice of restoring tidally restricted salt marshes. A Spartina‐dominated valley marsh at Barn Island Wildlife Management Area, Stonington, Connecticut, was tidally restricted in 1946 and consequently converted mostly to Typha angustifolia. With the re‐introduction of tidal flooding in 1978, much of the marsh has reverted to Spartina alterniflora. Using a geographical information system (GIS), this study measures restoration success by the extent of geographical similarity between the vegetation of the restored marsh and the pre‐impounded marsh. Based on geographical comparisons among different hydrologic states, pre‐impounded (1946), impounded (1976), and restored (1988) tidal marsh restoration is a convergent process. Although salt marsh species currently dominate the restored system, the magnitude of actual agreement between the pre‐impounded vegetation and that of the restored marsh is only moderate. Further restoration of the salt marsh vegetation may be limited by continued tidal restriction, marsh surface subsidence, and reduced accretion rates. General trends of recovery are identified using a gradient approach and the geographic pattern’ of vegetation change. In the strictest sense, if restoration refers only to vegetation types that geographically replicate preexisting types, then only 28% of the marsh has been restored. Restoration in a broader sense, however, representing the original salt marsh vegetation regardless of spatial position, amounts to 63% restored. Unrestored marsh, dominated by Typha angustifolia and Phragmites australis, remains at 37%. By emphasizing trends during vegetation recovery, this evaluation technique aims to understand the restoration process, direct future research goals, and ultimately aid in future restoration projects.
The Impact of Storage of Soils during Opencast Mining on the Microbial Community: A Strategist Theory Interpretation
Authors: Harris J. A. , Birch P. , Short K. C. 
Published: April 2006

AbstractThe microbial community in a soil stripped and stored during opencast coal mining was analyzed. There were significant effects of soil disturbance on the microbial community: in particular, there were large decreases in the total microbial biomass, as determined by ATP analysis, and numbers of fungal propagules as a result of the store construction process, but there was no significant effect on the numbers of bacteria. During the subsequent months of storage there was a flush in the numbers of bacteria, with gram‐negative bacteria showing an increase of nearly 700% in comparison to the control. During this time there was a steady accumulation in the amount of ammonium in the deepest part of the soil store, indicating the onset of anaerobiosis. These changes may be interpreted in terms of lifestyle strategy theory (Grime 1979). The bacteria exhibit behavior typical of R‐strategists, or ruderal species, taking advantage of the nutrients made available by the death of fungal biomass during store construction. Fungi respond as C‐strategists, or competitors, and they are severely affected by store construction‐and unable to persist deep in the anaerobic part of the store. In contrast, anaerobes, S‐strategists or stresstolerators, are able to survive under the same conditions. These changes have serious implications for the restoration of systems using stored topsoil as a resource. The microbial population has been altered in terms of its size and composition. Many of the fungi required for adequate breakdown and incorporation of organic matter will be absent, and the soils will be generally poor in microbial biomass. This will lead to inadequate nutrient cycling and poor soil structural stability, two factors essential for the restoration of a self‐sustaining ecosystem.
Use of Terrestrial Arthropods to Evaluate Restored Riparian Woodlands
Authors: Williams Kathy S. 
Published: April 2006

AbstractThe goal of this study was to use terrestrial arthropods to help evaluate the progress of a riparian restoration effort along the San Luis Rey River in California by comparing characteristics of the arthropod community at the reconstructed system to those of a naturally occurring riparian woodland used as a reference site. Insects and other arthropods were sampled throughout 1989–1991 using pan trapping and sweep sampling of dominant plants. Assemblages of taxa were monitored as indicators of functional groups that influence ecosystem processes: pollinators, herbivores, predators, parasites, and detritivores. Relative abundances of indicator assemblages were compared between sites to evaluate the establishment and maintenance of processes critical for the natural function of the reconstructed riparian ecosystem. A major objective of this project was to create habitat for the Least Bell's Vireo, so a group of potential prey items was designated to indicate vireo food resources. Over 230,000 arthropods were identified to order or family and by size. Insect communities developed rapidly at the restored habitat. Although the abundance of all arthropods was lower at the reconstructed site than at the reference site, the same orders were present after three years in similar proportions at both locations, and mean abundances were within an order of magnitude of each other. Abundance of certain groups, such as detritivores, suggested that arthropods had propagated rapidly at the restoration site, a possible indication of resiliency. Relatively low numbers of other arthropods, such as predators and parasites, at the reconstructed site indicated the need for continued monitoring. The decline of pollinators and herbivores by 1991 at the reconstructed site suggested that they may have immigrated or been introduced with transplanted vegetation in 1989, but have had difficulty colonizing the site. Although the Least Bell's Vireos were seen foraging at the restored site after three years, no nests were found. Nesting is anticipated, however, as the site matures.
Lag in Stream Channel Adjustment to Livestock Exclosure, White Mountains, California
Authors: Kondolf G. Mathias 
Published: April 2006

AbstractLivestock have been excluded from riparian zones along many streams in western North America in an effort to restore aquatic and riparian habitat degraded by livestock grazing. Within these exclosures, channel adjustment to elimination of grazing pressure may lag behind plant recovery because of the time required to deposit sediment along the vegetated banks of the stream channel. Moreover, unless grazing is eliminated from the watershed, the channel within the exclosure must still accommodate increased runoff and sediment loads from upstream. This hydrologic regime may prevent a return to predisturbance channel morphology. Cross sections of the North Fork Cottonwood Creek in the White Mountains of California showed no significant difference in channel width within and downstream of a 24‐year‐old exclosure, despite a lush growth of stream bank vegetation that gives the impression of a narrower channel within the exclosure.
Reproducing Bobcats to Cumberland Island, Georgia
Authors: Diefenbach Duane R. , Baker Leslie A. , James William E. , Warren Robert J. , Conroy Michael J. 
Published: April 2006

AbstractMany felids are threatened by loss of habitat, lack of genetic diversity, and over‐exploitation. The reintroduction of bobcats (Felis rufus) to Cumberland Island, Georgia provided an opportunity to reintroduce a mid‐sized felid without the concern for species survival that is paramount with endangered species. We captured bobcats from the coastal plain region of Georgia, briefly held them in captivity, and released them on Cumberland Island. We describe and evaluate the protocols and techniques used to accomplish the reintroduction. Future reintroductions of felids should consider the problem of post‐release dispersal, although our island was relatively isolated and inhibited dispersal. Also, any reintroduction effort should invest effort and resources into post‐release monitoring of the population. Empirical knowledge about the effects of spatial distribution, genetics, population dynamics, especially mechanisms of population regulation, behavior, and environmental conditions on the viability of populations is critical to the conservation of endangered species. Future research of the bobcats on Cumberland Island will be able to address aspects of the population and genetic dynamics of a small, insular felid population.
Biology and Management of Sagittaria latifolia Willd (Broad‐leaf Arrow‐head) for Wetland Restoration and Creation
Authors: Marburger Joy E. 
Published: April 2006

Abstract Sagittaria latifolia Willd. is commonly used for wetland enhancement, restoration, and creation. It is a C3 species that is widely distributed in southeastern Canada and the eastern half of the United States. It provides habitat and food benefits to waterfowl and improves water quality in wetlands. Monoecious and dioecious varieties occur in the U.S. that exhibit different life history characteristics. Clonal spread occurs through growth of rhizomes and tubers. S. latifolia grows in a wide range of fresh water and soil conditions. It persists in stabilized water levels at depths of less than 50 cm and few drawdowns. The species tolerates and assimilates high levels of nutrients and heavy metals. There is a limited data base on the installation and management of the species. Tubers and plants are preferred plant materials for field establishment. Herbivory by insects, waterfowl, and other animals may greatly reduce planting success. Future studies relevant to improvement of propagule storage, planting conditions, and management of mature plants for wetland projects are suggested.