bluuebunny/crossref_metadata_2025 huggingface dataset:
A Strategy for Restoration of Montane Forest in Anthropogenic Fern Thickets in the Dominican Republic
Authors: Slocum Matthew G. , Mitchell Aide T. , Zimmerman Jess K. , Navarro Luis
Published: December 2006

Deforested tropical areas are often colonized by competitive ferns that inhibit forest succession. In thickets of such a fern (Dicranopteris pectinata), we investigated methods for initiating restoration of tropical montane forest in the Ébano Verde Scientific Reserve (Dominican Republic). In clearings in the thickets, growth and survivorship of 18 common early‐ and late‐successional woody species were tested, with and without fertilizer (poultry litter). Three years after sowing, life history did not affect survivorship, but early‐successional species grew faster than late‐successional species (height increase 153 ± 103 cm vs. 81 ± 67 cm [mean ± 1 SD]).Inga fagifolia, a late‐successional species, andAlchornea latifolia, an early‐successional species, had 160 ± 62 cm mean height increase, and low mortality rates (<4%). In contrast, four late‐successional species (Cyrilla racemiflora, Myrcia deflexa, Prestoea acuminatavar.montana, andMora abbottii), and one early‐successional species,Ocotea leucoxylon,had approximately 39% mortality and height increase of 43 ± 48 cm.Brunellia comocladifoliahad high mortality (55%), but averaged 340 ± 201 cm height increase, and was the only species whose growth was improved by fertilization. Fertilization improved survivorship of only one species,Piper aduncum. After three years, soils in the clearings had low pH and available P and did not differ significantly from soils in thickets. However, based on the growth rates and survivorship of sown woody plants, these soils did not appear to be a barrier for restoration. Although a complementary study demonstrated substantial natural regeneration, active planting should be used to increase plant density and diversity, especially where natural regeneration is poor.
Landscape‐Scale Forest Habitat Relationships to Tassel‐Eared Squirrel Populations: Implications for Ponderosa Pine Forest Restoration
Authors: Dodd Norris L. , Schweinsburg Raymond E. , Boe Susan
Published: December 2006

Pinus ponderosa(ponderosa pine) forest ecosystem restoration is a growing emphasis in the southwestern United States to address over 120 years of forest structure change, decreased forest health, and increased potential for disease and wildfire. Restoration treatments replicating pre‐settlement conditions may reduce tree density by 98%, are detrimental to canopy‐dependent wildlife such as tassel‐eared squirrel (Sciurus aberti), particularly at the patch scale, and are of concern when applied at the landscape scale. We examinedS. abertipopulation dynamics in north‐central Arizona, U.S.A., from 1999 to 2002 at nine 280‐ha sites oriented along a landscape gradient of varying proportions (4.6–99.2%) of unlogged, high‐quality (HQ) habitats within a matrix of intensively thinned low‐quality habitat. Our objectives were to estimateS. abertidensity, juvenile recruitment, and survival across this gradient; quantify patch‐ and landscape‐scale habitat relationships to populations; evaluate possible habitat thresholds in squirrel population response; and develop forest management recommendations. In regression models, both patch‐scale and landscape‐scale parameters influenced squirrel populations. At the patch scale, number of interlocking canopy trees was added most frequently, whereas the proportion of HQ habitat was the landscape‐scale variable added in five of seven models. Recruitment and survival at dense, HQ plots were inversely related to number of small, sapling‐sized trees. Nonlinear thresholds in density and recruitment occurred when the proportion of HQ habitat at study sites was between 24 and 42%. Our study points to the importance of maintaining HQ habitat in mesoreserves on the landscape at or above this threshold range, as well as pursing a mix of forest management prescriptions in the matrix surrounding mesoreserves to achieve wildlife, forest restoration, and fire risk reduction objectives.
Assessing Targets for the Restoration of Herbaceous Vegetation in Ponderosa Pine Forests
Authors: Laughlin Daniel C. , Moore Margaret M. , Bakker Jonathan D. , Casey Cheryl A. , Springer Judith D. , Fulé Peter Z. , Covington W. Wallace
Published: December 2006

A restoration project is considered a success when the initial target is met, but many targets are plausible. We evaluated the success of a restoration project in its 11th year since treatment in a southwestern ponderosa pine–bunchgrass community and the appropriateness of several targets. We measured the responses of (1) total standing crop; (2) standing crop of five functional groups (C3and C4graminoids, leguminous forbs, and nonleguminous perennial and annual forbs); (3) graminoid community composition; and (4) standing crop of five common graminoid species (Festuca arizonica,Muhlenbergia montana,Elymus elymoides,Carex geophila, andPoa fendleriana). Targets were quantified in remnant grass patches, which provided the standards for these targets, and were assessed in three other forest patch types (pre‐settlement tree patches, post‐settlement tree patches, and patches where all post‐settlement trees were removed). Patches where all post‐settlement trees were removed reached target levels for total standing crop, C3and C4graminoid standing crop, graminoid community composition, andM. montana,E. elymoides,andC. geophilastanding crops. Standing crop of legumes and ofF. arizonicadid not increase over time in any patch type. Targets were not met in pre‐settlement patches or in patches where some post‐settlement trees were left standing, suggesting that it is unrealistic to expect equal responses across all patch types. If increasing herbaceous standing crop is a major goal, practitioners should create gaps within the pine forest canopy.
Influence of Aboveground Biomass Removal on Nitrogen Mineralization in a Restored Tallgrass Prairie
Authors: Tix Daniel , Hebberger Jo Anna , Charvat Iris
Published: December 2006

Prescribed burning in prairies influences soil nitrogen (N), which is the primary nutrient that limits plant growth and is an important factor in plant competition and diversity. The primary objective of the experiment described here was to better understand the changes in net N mineralization that occur after a fire. We compared soil properties after a fire with those following vegetation removal by mowing and raking in a restored prairie in southeastern Minnesota. The treatments occurred in the spring of two consecutive years. Calcium oxide, burnt lime, was added to some of the raked plots in the first year to mimic the deposition of basic cations during a fire, which cause an increase in soil pH. Aboveground biomass removal by raking or by burning had similar effects on soil moisture, temperature, and inorganic N. The removal treatments caused warmer and drier soil than in the untreated plots. The change in net N mineralization after raking was unaffected by the addition of lime. In the first year, with low rainfall, removal caused net N mineralization rates similar to those in the untreated controls, but during the second year, with heavy rainfall, net N mineralization rates were significantly higher after removal. We predict that if water is sufficient, increased soil temperature after biomass removal will increase soil microbial activity and net N mineralization, but during drought, water will limit microbial activity. Furthermore, depending on soil N concentrations, which are very high at this study site, altered soil microbial activity will have variable effects on net N mineralization.
Effect of Seed Source, Topsoil Removal, and Plant Neighbor Removal on Restoring California Coastal Prairies
Authors: Buisson Elise , Holl Karen D. , Anderson Sean , Corcket Emmanuel , Hayes Grey F. , Torre Franck , Peteers Alain , Dutoit Thierry
Published: December 2006

Grasslands are hot spots of biodiversity but are now widely threatened by changes in patterns of disturbances, such as grazing and fire regimes, exotic species invasions, and cultivation. The goal of this experiment was to find the most appropriate combination of treatments to reintroduce Danthonia californica, a formerly dominant perennial bunchgrass, into degraded California coastal prairies. Danthonia californica was sown from seed and transplanted at two sites and at two grazing intensities (grazed/ungrazed) in a multifactorial experiment testing the effects of (1) local versus nonlocal seed sources; (2) topsoil removal; and (3) reduction of plant neighbors. Seed emergence was very low, suggesting that transplanting may be a better option to reintroduce D. californica. Although transplants grown from nonlocal seeds survived better initially at both sites, transplants from local seeds had higher survival after 1.5 year at one site. This suggests that short‐term plant establishment studies may be misleading. Topsoil removal greatly enhanced transplant survival, and neighbor removal primarily increased transplant growth. Our results suggest that removing topsoil prior to transplanting seedlings grown from local seeds is the most promising method to reintroduce D. californica. However, the benefits of removing topsoil to provide safe sites for plant establishment should be weighed carefully against potential negative effects on the native seed bank and microbial communities on a site‐specific basis.
The Use of Case Studies in Establishing Feasibility for Wetland Restoration
Authors: Hopfensperger Kristine N. , Engelhardt Katharina A. M. , Seagle Steven W.
Published: December 2006

Establishing restoration feasibility is a multifaceted process that requires consideration of the ecological, social, and economic conditions of a given site. Examining completed restoration projects that report successes and failures may enhance this complex decision‐making process. We describe five completed wetland restoration projects and identify commonalities among them to inform the process of establishing feasibility for proposed restoration projects. Most of the case studies identified the need to gather preexisting and historical information, develop scenarios through hydrologic modeling, study the restoration materials, use best professional judgement for unanswered questions, establish multigroup collaboration, gain public support from stakeholders, and monitor postrestoration. We applied these lessons to a study that evaluated the feasibility of restoring Dyke Marsh Preserve, a tidal freshwater marsh in Virginia that the National Park Service is mandated to preserve. We found that the use of case studies substantially increased confidence in the decision‐making process by focusing discussions on the most important ecological, social, and economic aspects of a potential restoration.
Response of Native and Exotic Grasses to Increased Soil Nitrogen and Recovery in a Postfire Environment
Authors: Hunter Molly E. , Omi Philip N.
Published: December 2006

Native plant recovery following wildfires is of great concern to managers because of the potential for increased water run‐off and soil erosion associated with severely burned areas. Although postfire seeding with exotic grasses or cultivars of native grasses (seeded grasses) may mitigate the potential for increased run‐off and erosion, such treatments may also be detrimental to long‐term recovery of other native plant species. The degree to which seeded grasses dominate a site and reduce native plant diversity may be a function of the availability of resources such as nitrogen and light and differing abilities of native and seeded grasses to utilize available resources. We tested the hypothesis that seeded grasses have higher growth rates than native grasses when nitrogen and light availability is high in a greenhouse experiment. To determine how differing resource utilization strategies may affect distribution of native and seeded grasses across a burned landscape, we conducted botanical surveys after a wildfire in northern New Mexico, U.S.A., one and four years after the fire. In the greenhouse study we found seeded grasses to produce significantly more biomass than native grasses when nitrogen and light availability was high. Seeded grasses increased in cover from 1–4 years after the fire only in areas where total soil nitrogen was higher. Increased cover of seeded grasses did not affect recovery of native grasses, but it did lead to reduced native species richness at small scales. The potential negative long‐term consequences of seeding with exotic grasses should be considered in postfire rehabilitation treatments.
Enhancing Native Forb Establishment and Persistence Using a Rich Seed Mixture
Authors: Sheley Roger L. , Half Melissa L.
Published: December 2006

Establishing native forbs is crucial for invasive plant management and restoring a desirable plant community. Our objectives were to determine (1) if increasing forb seed density results in increased forb establishment; (2) if a species‐rich mixture of forbs has greater establishment and survivorship than a single species; and (3) if mixtures of forbs are more competitive with Spotted knapweed (Centaurea maculosa) than a forb monoculture. To test our first two objectives, we seeded monocultures of Purple coneflower (Echinacea angustifolia), Arrowleaf balsamroot (Balsamorhiza sagittata), Annual sunflower (Helianthus annuus), Dotted gayfeather (Liatris punctata), Western white yarrow (Achillea millefolium), Sticky geranium (Geranium viscosissimum), as well as a mixture of all forbs. Pots were seeded at 800 or 2,000 seeds/m2 and watered twice or thrice weekly. The highest seed density produced the highest plant density, which averaged 4.35 plants/pot. The density of the mixture was similar to the mean density seen for individual species, and it doubled in response to the highest seed density. To test our third objective, Spotted knapweed and Purple coneflower were arranged in an addition series matrix with a maximum total density of 4,000 seeds/pot. We found that the forb mixture was seven times more competitive with Spotted knapweed than Purple coneflower alone. Using a mixture of forbs rather than a single species enhances forb establishment in various and unpredictable environments because the mixture possesses a variety of traits that may match year–year and site–site conditions. Once established, the mixture may have a greater chance of persisting than a monoculture.
Forest Stand Characteristics Altered by Restoration Affect Western Bluebird Habitat Quality
Authors: Wightman Catherine S. , Germaine Stephen S.
Published: December 2006

Forest managers are setting Ponderosa pine (Pinus ponderosa) forests in the southwestern United States on a trajectory toward a restored ecosystem by reducing tree densities and managing with prescribed fire. The process of restoration dramatically alters forest stands, and the effects of these changes on wildlife remain unclear. Our research evaluated which aspects of habitat alteration from restoration treatments may be affecting the habitat quality of Western Bluebird (Sialia mexicana), an insectivorous songbird whose populations are declining. Habitat loss resulting from fire‐suppression activities may be partially responsible for their population declines; thus, the bluebird is a good representative species for assessing how the reconstruction of presuppression forest conditions can affect wildlife. We measured habitat variables at 63 successful and 19 unsuccessful Western Bluebird nests in 1999–2001 and 2003. We compared habitat models that represented bluebird biology and habitat changes from restoration. Two models of nest success that included (1) an increased herbaceous and bare ground cover and (2) increased Gambel oak (Quercus gambelii) densities and reduced Ponderosa pine densities were most supported by the data. Increased herbaceous ground cover and Gambel oak density likely represent improved invertebrate assemblages and thus improved forage abundance for nesting bluebirds. Lower Ponderosa pine densities may provide bluebirds with open perches from which to hunt and thereby improve the availability of invertebrates as a food source. We also provide a landscape‐scale example of changes to bluebird habitat quality from treatments, which we recommend as a useful tool in restoration planning.
Taste deficits related to dental deafferentation: an electrogustometric study in humans
Authors: Boucher Yves , Berteretche Marie‐Violaine , Farhang Farnaz , Arvy Marie‐Pierre , Azérad Jean , Faurion Annick
Published: December 2006

Dental treatments, the prevalence of which increases with age, can cause orofacial somatosensory deficits. In order to examine whether they may also affect taste sensitivity, electrogustometric thresholds were measured at 9 loci on the tongue surface in 391 healthy non‐smoking, non‐medicated subjects. Results showed that the greater the number of deafferented teeth, the higher the thresholds. Irrespective of age, subjects with more than 7 deafferented teeth exhibited significantly higher thresholds than subjects with fewer than 7 deafferented teeth. Conversely, across age groups, no statistical difference was observed among subjects with no, or few, deafferented teeth. Hence, a taste deficit, which was not correlated to aging, was observed. An association was noticed between the location of taste deficits and the location of deafferented teeth. Higher thresholds at anterior sites, with no possible traumatic injury relationship, suggested that neurophysiological convergence between dental somatosensory and taste pathways – possibly in the nucleus tractus solitarius – could be responsible for these relative decreases of taste sensitivity when dental afferences were lacking. Among trigeminal contributions, lingual nerve and inferior alveolar nerve may synergize taste.
Mothers' perceptions of children's refusal to undergo dental treatment: an exploratory qualitative study
Authors: De Oliveira Vania J. , Da Costa Luciane R. de R. S. , Marcelo Vânia C. , Lima Alessandra R. de A.
Published: December 2006

Very little is known about mothers' beliefs concerning children's refusal of dental treatment. This qualitative study aimed to explore mothers' perceptions of their children's refusal to submit to dental treatment. Semistructured interviews were conducted with 14 mothers of 4–12‐yr‐old children resistant to dental treatment who were attending two pediatric dentists. Thematic content analysis was used to interpret the data. From this, three categories were developed and labeled origins of child behavior, caregiver attitudes, and the culture of resistance. The origins of the children's behavior were related to the childs' temperament, behavior disorders, lack of affection, level of development, and refusal to submit to health procedures or other situations. Caregiver's attitudes included discipline, protection, incoherence, partnership in dental treatment, and mother–child feeling. The culture of resistance referred to the parents' or guardians' refusal of dental treatment and the mothers' recognition of this. In conclusion, the wide variety of mothers' accounts reinforced the idea that every child is unique, and it is not possible to standardize child behavior models in a dental setting.
Influence of the condition of the adjacent tooth surface on fluorescence measurements for the detection of approximal caries
Authors: Lussi A. , Zimmerli B. , Hellwig E. , Jaeggi T.
Published: December 2006

The aim of this study was to test whether the status of the adjacent tooth surface has an influence on the signal of a new laser fluorescence (LF) device for the detection of approximal caries. Seventy‐eight teeth were selected from a pool of extracted permanent human molars, frozen at −20°C until use. Before being measured the teeth were defrosted, cleaned, and any calculus removed. As a control, a defined approximal surface of each tooth was measured with the LF device holding the tip with the detecting‐ and the reverse‐side on it, but without a neighboring tooth contacting the surface. The proximal site under examination was then placed adjacent to a tooth, which had deep dentinal caries, a composite restoration, a provisional ZnO‐Eugenol restoration, or a ceramic restoration. The adjacent tooth with the ZnO‐Eugenol restoration, the composite restoration, and the dentinal caries all demonstrated a statistically significant increase of LF readings on sound tooth surfaces. Teeth with enamel or dentinal caries were only slightly (and not statistically significantly) influenced by the different types of neighboring surfaces compared with the control LF readings. It can be concluded that caries detection of approximal tooth surfaces with the new LF system might be influenced by the condition of the adjacent tooth surface.
Differential expression of receptor activator of nuclear factor‐κB ligand and osteoprotegerin mRNA in periodontal diseases
Authors: Bostancı N. , İlgenli T. , Emingil G. , Afacan B. , Han B. , Töz H. , Berdeli A. , Atilla G. , McKay I. J. , Hughes F. J. , Belibasakis G. N.
Published: December 2006

Background and Objective:  Receptor activator of nuclear factor‐κB ligand (RANKL) is responsible for the induction of osteoclastogenesis and bone resorption, whereas its decoy receptor, osteoprotegerin, can directly block this action. Because this dyad of cytokines is crucial for regulating the bone remodelling process, imbalances in their expression may cause a switch from the physiological state to enhanced bone resorption or formation. This study investigated the mRNA expression of RANKL and osteoprotegerin, as well as their relative ratio, in the gingival tissues of patients with various forms of periodontal diseases.

Material and Methods:  Gingival tissue was obtained from nine healthy subjects and 41 patients, who had gingivitis, chronic periodontitis, generalized aggressive periodontitis, and chronic periodontitis and were receiving immunosuppressant therapy. Quantitative real‐time polymerase chain reaction was employed to evaluate the mRNA expression of RANKL and osteoprotegerin in these tissues.

Results:  Compared with healthy individuals, patients in all periodontitis groups, but not those with gingivitis, exhibited stronger RANKL expression and a higher relative RANKL/osteoprotegerin ratio. In addition, osteoprotegerin expression was weaker in patients with chronic periodontitis. When patients with generalized aggressive periodontitis and chronic periodontitis were compared, the former exhibited stronger RANKL expression, whereas the latter exhibited weaker osteoprotegerin expression, and there was no difference in their relative ratio. When chronic periodontitis patients were compared with chronic periodontitis patients receiving immunosuppressant therapy, osteoprotegerin, but not RANKL, expression was stronger in the latter.

Conclusion:  This study demonstrates that RANKL and osteoprotegerin expression are differentially regulated in various forms of periodontitis, and the relative RANKL/osteoprotegerin ratio appears to be indicative of disease occurrence. This information may confer diagnostic and therapeutic value in periodontitis.
A Role of Myosin Vb and Rab11‐FIP2 in the Aquaporin‐2 Shuttle
Authors: Nedvetsky Pavel I. , Stefan Eduard , Frische Sebastian , Santamaria Katja , Wiesner Burkhard , Valenti Giovanna , Hammer John A. , Nielsen Søren , Goldenring James R. , Rosenthal Walter , Klussmann Enno
Published: December 2006

Arginine‐vasopressin (AVP) regulates water reabsorption in renal collecting duct principal cells. Its binding to Gs‐coupled vasopressin V2 receptors increases cyclic AMP (cAMP) and subsequently elicits the redistribution of the water channel aquaporin‐2 (AQP2) from intracellular vesicles into the plasma membrane (AQP2 shuttle), thereby facilitating water reabsorption from primary urine. The AQP2 shuttle is a paradigm for cAMP‐dependent exocytic processes. Using sections of rat kidney, the AQP2‐expressing cell line CD8, and primary principal cells, we studied the role of the motor protein myosin Vb, its vesicular receptor Rab11, and the myosin Vb‐ and Rab11‐binding protein Rab11‐FIP2 in the AQP2 shuttle. Myosin Vb colocalized with AQP2 intracellularly in resting and at the plasma membrane in AVP‐treated cells. Rab11 was found on AQP2‐bearing vesicles. A dominant‐negative myosin Vb tail construct and Rab11‐FIP2 lacking the C2 domain (Rab11‐FIP2‐ΔC2), which disrupt recycling, caused condensation of AQP2 in a Rab11‐positive compartment and abolished the AQP2 shuttle. This effect was dependent on binding of myosin Vb tail and Rab11‐FIP2‐ΔC2 to Rab11. In summary, we identified myosin Vb as a motor protein involved in AQP2 recycling and show that myosin Vb‐ and Rab11‐FIP2‐dependent recycling of AQP2 is an integral part of the AQP2 shuttle.
Thermodynamic characterization of interleukin‐8 monomer binding to CXCR1 receptor N‐terminal domain
Authors: Fernando Harshica , Nagle Gregg T. , Rajarathnam Krishna
Published: December 2006

Chemokines elicit their function by binding receptors of the G‐protein‐coupled receptor class, and the N‐terminal domain (N‐domain) of the receptor is one of the two critical ligand‐binding sites. In this study, the thermodynamic basis for binding of the chemokine interleukin‐8 (IL‐8) to the N‐domain of its receptor CXCR1 was characterized using isothermal titration calorimetry. We have shown previously that only the monomer of IL‐8, and not the dimer, functions as a high‐affinity ligand, so in this study we used the IL‐8(1–66) deletion mutant which exists as a monomer. Calorimetry data indicate that the binding is enthalpically favored and entropically disfavored, and a negative heat capacity change indicates burial of hydrophobic residues in the complex. A characteristic feature of chemokine receptor N‐domains is the large number of acidic residues, and experiments using different buffers show no net proton transfer, indicating that the CXCR1 N‐domain acidic residues are not protonated in the binding process. CXCR1 N‐domain peptide is unstructured in the free form but adopts a more defined structure in the bound form, and so binding is coupled to induction of the structure of the N‐domain. Measurements in the presence of the osmolyte, trimethylamine N‐oxide, which induces the structure of unfolded proteins, show that formation of the coupled N‐domain structure involves only small ΔH and ΔS changes. These results together indicate that the binding is driven by packing interactions in the complex that are enthalpically favored, and are consistent with the observation that the N‐domain binds in an extended form and interacts with multiple IL‐8 N‐loop residues over a large surface area.
Inhibition of cobalamin‐dependent methionine synthase by substituted benzo‐fused heterocycles
Authors: Banks Elizabeth C. , Doughty Stephen W. , Toms Steven M. , Wheelhouse Richard T. , Nicolaou Anna
Published: December 2006

The cobalamin–dependent cytosolic enzyme, methionine synthase (EC.2.1.1.13), catalyzes the remethylation of homocysteine to methionine using 5‐methyltetrahydrofolate as the methyl donor. The products of this remethylation – methionine and tetrahydrofolate – participate in the active methionine and folate pathways. Impaired methionine synthase activity has been implicated in the pathogenesis of anaemias, cancer and neurological disorders. Although the need for potent and specific inhibitors of methionine synthase has been recognized, there is a lack of such agents. In this study, we designed, synthesized and evaluated the inhibitory activity of a series of substituted benzimidazoles and small benzothiadiazoles. Kinetic analysis revealed that the benzimidazoles act as competitive inhibitors of the rat liver methionine synthase, whilst the most active benzothiadiazole (IC50 = 80 µm) exhibited characteristics of uncompetitive inhibition. A model of the methyltetrahydrofolate‐binding site of the rat liver methionine synthase was constructed; docking experiments were designed to elucidate, in greater detail, the binding mode and reveal structural requirements for the design of inhibitors of methionine synthase. Our results indicate that the potency of the tested compounds is related to a planar region of the inhibitor that can be positioned in the centre of the active site, the presence of a nitro functional group and two or three probable hydrogen‐bonding interactions.
Fowlicidin‐3 is an α‐helical cationic host defense peptide with potent antibacterial and lipopolysaccharide‐neutralizing activities
Authors: Bommineni Yugendar R. , Dai Huaien , Gong Yu‐Xi , Soulages Jose L. , Fernando Samodha C. , DeSilva Udaya , Prakash Om , Zhang Guolong
Published: December 2006

Cathelicidins are an important family of cationic host defense peptides in vertebrates with both antimicrobial and immunomodulatory activities. Fowlicidin‐1 and fowlicidin‐2 are two newly identified chicken cathelicidins with potent antibacterial activities. Here we report structural and functional characterization of the putatively mature form of the third chicken cathelicidin, fowlicidin‐3, for exploration of its therapeutic potential. NMR spectroscopy revealed that fowlicidin‐3 comprises 27 amino‐acid residues and adopts a predominantly α‐helical structure extending from residue 9 to 25 with a slight kink induced by a glycine at position 17. It is highly potent against a broad range of Gram‐negative and Gram‐positive bacteria in vitro, including antibiotic‐resistant strains, with minimum inhibitory concentrations in the range 1–2 µm. It kills bacteria quickly, permeabilizing cytoplasmic membranes immediately on coming into contact with them. Unlike many other host defense peptides with antimicrobial activities that are diminished by serum or salt, fowlicidin‐3 retains bacteria‐killing activities in the presence of 50% serum or physiological concentrations of salt. Furthermore, it is capable of suppressing lipopolysaccharide‐induced expression of proinflammatory genes in mouse macrophage RAW264.7 cells, with nearly complete blockage at 10 µm. Fowlicidin‐3 appears to be an excellent candidate for future development as a novel antimicrobial and antisepsis agent, particularly against antibiotic‐resistant pathogens.
Stimulation of fibroblast proliferation by neokyotorphin requires Ca2+ influx and activation of PKA, CaMK II and MAPK/ERK
Authors: Sazonova Olga V. , Blishchenko Elena Yu. , Tolmazova Anna G. , Khachin Dmitry P. , Leontiev Konstantin V. , Karelin Andrey A. , Ivanov Vadim T.
Published: December 2006

Neokyotorphin [TSKYR, hemoglobin α‐chain fragment (137–141)] has previously been shown to enhance fibroblast proliferation, its effect depending on cell density and serum level. Here we show the dependence of the effect of neokyotorphin on cell type and its correlation with the effect of protein kinase A (PKA) activator 8‐Br‐cAMP, but not the PKC activator 4β‐phorbol 12‐myristate, 13‐acetate (PMA). In L929 fibroblasts, the proliferative effect of neokyotorphin was suppressed by the Ca2+L‐type channel inhibitors verapamil or nifedipine, the intracellular Ca2+ chelator 1,2‐bis(2‐aminophenoxy)ethane‐N,N,N′,N′‐tetraacetic acid acetoxymethyl ester, kinase inhibitors H‐89 (PKA), KN‐62 (Ca2+/calmodulin‐dependent kinase II) and PD98059 (mitogen‐activated protein kinase). The proliferative effect of 8‐Br‐cAMP was also suppressed by KN‐62 and PD98059. PKC suppression (downregulation with PMA or inhibition with bisindolylmaleimide XI) did not affect neokyotorphin action. The results obtained point to a cAMP‐like action for neokyotorphin.
Vitamin C
Authors: Linster Carole L. , Van Schaftingen Emile
Published: December 2006

Vitamin C, a reducing agent and antioxidant, is a cofactor in reactions catalyzed by Cu+‐dependent monooxygenases and Fe2+‐dependent dioxygenases. It is synthesized, in vertebrates having this capacity, from d‐glucuronate. The latter is formed through direct hydrolysis of uridine diphosphate (UDP)‐glucuronate by enzyme(s) bound to the endoplasmic reticulum membrane, sharing many properties with, and most likely identical to, UDP‐glucuronosyltransferases. Non‐glucuronidable xenobiotics (aminopyrine, metyrapone, chloretone and others) stimulate the enzymatic hydrolysis of UDP‐glucuronate, accounting for their effect to increase vitamin C formation in vivo. Glucuronate is converted to l‐gulonate by aldehyde reductase, an enzyme of the aldo‐keto reductase superfamily. l‐Gulonate is converted to l‐gulonolactone by a lactonase identified as SMP30 or regucalcin, whose absence in mice leads to vitamin C deficiency. The last step in the pathway of vitamin C synthesis is the oxidation of l‐gulonolactone to l‐ascorbic acid by l‐gulonolactone oxidase, an enzyme associated with the endoplasmic reticulum membrane and deficient in man, guinea pig and other species due to mutations in its gene. Another fate of glucuronate is its conversion to d‐xylulose in a five‐step pathway, the pentose pathway, involving identified oxidoreductases and an unknown decarboxylase. Semidehydroascorbate, a major oxidation product of vitamin C, is reconverted to ascorbate in the cytosol by cytochrome b5 reductase and thioredoxin reductase in reactions involving NADH and NADPH, respectively. Transmembrane electron transfer systems using ascorbate or NADH as electron donors serve to reduce semidehydroascorbate present in neuroendocrine secretory vesicles and in the extracellular medium. Dehydroascorbate, the fully oxidized form of vitamin C, is reduced spontaneously by glutathione, as well as enzymatically in reactions using glutathione or NADPH. The degradation of vitamin C in mammals is initiated by the hydrolysis of dehydroascorbate to 2,3‐diketo‐l‐gulonate, which is spontaneously degraded to oxalate, CO2 and l‐erythrulose. This is at variance with bacteria such as Escherichia coli, which have enzymatic degradation pathways for ascorbate and probably also dehydroascorbate.
Temporal expression of c‐kit in spermatogenesis of two grasshopper species
Authors: ZHAO ZHUO , LÜ SHU‐MIN , XI GENG‐SI
Published: December 2006

Abstract
Two species of grasshoppers, Calliptamus abbreviatus (Ikonn.) and Shirakiacris shirakii (I. Bol.), were collected randomly in the Siping area of Jilin Province, China. By using immunohistochemical methods and statistical analysis, we observed and compared the temporal expression of c‐kit protein in four representative stages of spermatogenesis of the two grasshoppers, namely: spermatogonia; primary spermatocyte; secondary spermatocyte; and mature sperm. Results showed that there was c‐kit positive temporal expression at each stage of spermatogenesis, but there were different positive expression levels: (i) weak positive expression of c‐kit protein appeared in spermatogonia and the positive granules were thinner; (ii) strong positive expression of c‐kit protein existed in primary spermatocyte and positive granules became biggest among all developmental stages; (iii) c‐kit positive expression stayed stronger in secondary spermatocyte while positive granules became thinner; (iv) there was a strong positive expression of c‐kit and thinner positive granules in mature sperm, which distributed on head and tail; (v) the biggest c‐kit positive granules had been found massing at the end of spermary; and (vi) significant differences of c‐kit positive expression existed in spermatogenesis between two species of grasshoppers. The results indicated that c‐kit protein may play a crucial role in spermatogenesis and even retain the physiological action of sperms and fertilization in grasshoppers.
Ecological monophagy in Tasmanian Graphium macleayanum moggana with evolutionary reflections of ancient angiosperm hosts
Authors: SCRIBER J. MARK , ALLEN GEOFF R. , WALKER PAUL W.
Published: December 2006

Abstract
Local host plant specialization in an insect herbivore may be caused by numerous factors, including host‐specific natural enemy pressures or a local lack of suitable host‐plant choices that are available elsewhere in its range. Such local specialization or “ecological monophagy”, for whatever reason, may reflect reduced ability to behaviourally accept or physiologically utilize other allopatric hosts that are naturally used elsewhere by the species. We tested this feeding specialization hypothesis using the Tasmanian subspecies of Macleay's swallowtail butterfly, Graphium macleayanum moggana (Papilionidae), which uses only a single host‐plant species, Antherosperma moschatum (southern sassafras, of the Monimiaceae). Further north, this same butterfly species (G. m. macleayanum) uses at least 13 host‐plant species from seven genera and four families (Lauraceae, Rutaceae, Winteraceae, and Monimiaceae). Our larval feeding assays with G. m. moggana from Tasmania showed that certain Magnoliaceae and Lauraceae could support some larval growth to pupation. However, such growth was slower and survival was lower than observed on their normal southern sassafras host (Monimiaceae). We also found that toxicity of particular plant species varied tremendously within plant families (for both the Magnoliceae and the Monimiaceae).
Peptides by Extension at the N‐ or C‐terminii of Lysine
Authors: Katritzky Alan R. , Meher Geeta , Angrish Parul
Published: December 2006

Dipeptides 3a–g, (3a + 3a′), (3d + 3d′), (3l + 3l′)a and tripeptides 6a–e, (6b + 6b′), (6e + 6e′) incorporating Zε‐Lys were prepared in high yields (70–95%) and enantiopurity (≥97%) in partially aqueous acetonitrile solution by coupling using (i) Zε‐Lys with N‐(Z‐ and Fmoc‐aminoacyl)benzotriazoles 1a–g, (ii) Zε‐Lys with N‐Z‐dipeptidoylbenzotriazoles 5a–c, and (iii) N‐Fmocα‐Zε‐l‐Lys‐Bt 1h and amino acids 2a,c–e. Unnatural dipeptides 3h–j, (3h + 3h′) and tripeptides 6f were similarly prepared from Zα‐Lys. Retention of chirality was demonstrated by parallel experiments involving l‐Ala, dl‐Ala, l‐Met, and dl‐Met by NMR and HPLC analysis.
X‐linked spondylo‐epiphyseal dysplasia tarda in the Danish‐Swedish farm hound
Authors: Arnbjerg J. , Jensen A. L. , Olesen A. B.
Published: December 2006

In two litters from the same parents, three out of four males had an abnormally short leg and body length. Affected dogs showed signs of pain when moving, which could be eliminated by analgesia. On radiography, these animals had widened, radiolucent, irregularly bordered intervertebral disc spaces. When examined at seven months of age, the epiphyses appeared widened and irregular in shape and outline. General bone opacity in the vertebral column was lower in the affected male dogs than in the normal littermate. The affected dogs developed spondylosis and arthrosis of the larger limb joints. All affected dogs were euthanased on humane grounds, the eldest at the age of two years nine months. Based on the clinical and radiographic evidence, the condition seen in the male dogs described here resembles X‐linked spondylo‐epiphyseal dysplasia tarda caused by a collagenopathy due to malformation of COL2A1 as seen in human beings.
Generalised lymphadenomegaly associated with methimazole treatment in a hyperthyroid cat
Authors: Niessen S. J. M. , Voyce M. J. , De Villiers L. , Hargreaves J. , Blunden A. S. , Syme H. M.
Published: December 2006

A nine‐year‐old, domestic shorthair cat was diagnosed with hyperthyroidism and treated with methimazole, which resulted in lethargy, inappetence and marked generalised lymphadenomegaly within two weeks of initiation of therapy. Cytology, histopathology and immunohistochemistry were suggestive of atypical lymphoid hyperplasia. Cessation of treatment resulted in resolution of all clinical signs and physical abnormalities within two days. Subsequent treatment with radioactive iodine cured this cat of its hyperthyroidism. The lymphadenomegaly did not return at any stage and the cat is currently asymptomatic. Although methimazole administration for feline hyperthyroidism has been associated with many side effects, lymphadenomegaly has, to the authors’ knowledge, not been previously reported.
Results of pacemaker implantation in 104 dogs
Authors: Johnson M. S. , Martin M. W. S. , Henley W.
Published: December 2006

Objectives:To document the outcome, survival and complications involved in pacemaker implantation in dogs in a retrospective study.

Methods:Case records for all dogs in which pacemaker implantation was performed were reviewed.

Results:A total of 104 dogs underwent pacemaker implantation. Dogs were presented with atrioventricular (AV) block (71), sick sinus syndrome (25) or vasovagal syncope (eight). Age at presentation varied from six months to 13 years with a median age of seven years and two months. The Labrador was the most commonly represented breed (17 cases). All but one dog survived pacemaker implantation, with 93 showing resolution of their clinical signs while 10 dogs showed intermittent residual signs. One‐, three‐ and five‐year survival estimates were 86, 65 and 39 per cent, respectively. Major complications after implantation were documented in 15 dogs and three of these led to fatalities. Minor complications were noted in 23 dogs. Sudden death occurred in six dogs three to 55 months following successful pacemaker implantation.

ClinicalSignificance:Transvenous pacemaker implantation was successful in reducing or eliminating clinical signs in over 90 per cent of dogs with third‐degree atrioventricular (AV) block or sick sinus syndrome. In dogs with vasovagal syncope, six of eight dogs had greatly reduced frequency of collapse and two became asymptomatic. Although the procedure was associated with complications, these were rarely life threatening and good survival was documented in the majority of cases.
Perirenal expanding haematoma in a cat
Authors: Beraud R. , Carozzo C.
Published: December 2006

A four‐year‐old, entire male domestic cat was referred for assessment of a large abdominal mass of three‐weeks duration. Diagnostic imaging suggested the presence of either splenic neoplasia, an abdominal abscess or haematoma. A coeliotomy was performed and an enlarged, irregular mass, including the left kidney and adrenal gland, was identified. The mass was removed, requiring a left adrenalo‐uretero‐nephrectomy. The aorta was accidentally punctured during the procedure, resulting in paraplegia. Given a poor prognosis, the owners decided to have the cat euthanased. Histological examination of the mass was characteristic of a chronic expanding haematoma.
Quantitative and Functional Differences between Peripheral Blood Myeloid Dendritic Cells from Patients with Pleural and Parenchymal Lung Tuberculosis
Authors: Mendelson Marc , Hanekom Willem A. , Ntutela Siyabulela , Vogt Monica , Steyn Lafras , Maartens Gary , Kaplan Gilla
Published: December 2006

Dendritic cells (DCs) play a pivotal role in generating protective host immunity toMycobacterium tuberculosis. Few studies have addressed DC function in the context of active tuberculosis (TB), largely due to technical constraints in obtaining adequate numbers of DC from sick patients. We quantitated peripheral blood myeloid DCs (mDCs) and plasmacytoid DCs (pDCs) in the whole blood of patients with active TB and show that blood from patients with pleural TB was characterized by high circulating levels of mDCs. We also developed and optimized a novel whole-blood assay to study mDC production of the Th1-promoting cytokine interleukin 12 (IL-12) and upregulation of the maturation marker CCR7 after incubation with mycobacteria. We found that pleural TB was associated with increased IL-12 production and CCR7 expression compared to lung parenchymal disease. Our findings suggest important differences in innate immunity between patients with different forms of active TB, and this may contribute to the differences in natural history observed between the two groups.
Antibodies Specific for the High-Molecular-Weight Adhesion Proteins of NontypeableHaemophilus influenzaeAre Opsonophagocytic for both Homologous and Heterologous Strains
Authors: Winter Linda E. , Barenkamp Stephen J.
Published: December 2006

The HMW1/HMW2-like adhesion proteins of nontypeableHaemophilus influenzae(NTHI) are expressed by 75% of NTHI strains. Antibodies directed against these proteins are opsonophagocytic in vitro and are protective in an animal model of infection. The objective of the present study was to determine the opsonophagocytic activity of high-titer anti-HMW1/HMW2 immune sera against both homologous and heterologous NTHI strains. Chinchillas were immunized with purified HMW1/HMW2-like proteins from five prototype NTHI strains. Serum opsonophagocytic activity was monitored in an assay that uses a human promyelocytic cell line, HL-60, as the source of phagocytic cells. Preimmune sera did not demonstrate opsonophagocytic killing of any strains. In contrast, the immune sera demonstrated killing of the five homologous NTHI strains at titers ranging from 1:320 to 1:640. The immune sera also demonstrated killing of eight heterologous NTHI strains that express HMW1/HMW2-like proteins at titers ranging from 0 to 1:640. Killing of heterologous strains sometimes demonstrated a prozone phenomenon. None of the immune sera killed NTHI strains that did not express HMW1/HMW2-like proteins. Adsorption of immune sera with HMW1/HMW2-like proteins purified from either homologous or heterologous NTHI strains eliminated opsonophagocytic killing of homologous strains in most cases. These data demonstrate that antibodies produced following immunization with the HMW1/HMW2-like proteins are opsonophagocytic for both homologous and heterologous NTHI and strongly suggest that common epitopes recognized by functionally active antibodies exist on the HMW1/HMW2-like proteins of unrelated NTHI strains. The results argue for the continued investigation of the HMW1/HMW2-like proteins as potential vaccine candidates for the prevention of NTHI disease.
Community-Based Seroepidemiological Survey of Hepatitis E Virus Infection in Catalonia, Spain
Authors: Buti Maria , Domínguez Àngela , Plans Pere , Jardí Rossend , Schaper Mélani , Espuñes Jordi , Cardeñosa Neus , Rodríguez-Frías Francisco , Esteban Rafael , Plasència Antoni , Salleras Luis
Published: December 2006

The objective of the study was to investigate the prevalence of immunoglobulin G (IgG) antibodies to hepatitis E virus (HEV) infection in a population sample from Catalonia and to analyze the demographic and clinical variables associated with the presence of these antibodies. A total of 1,280 subjects between 15 and 74 years of age were selected randomly from urban and rural areas. Data for sociodemographic and clinical variables were collected by using a questionnaire. IgG antibodies to HEV were determined by an immunoenzymatic method. The odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated for studied variables. Multiple logistic regression analysis was used to determine which variables were independently associated with the prevalence of HEV infection. Anti-HEV antibodies were detected in 96 (7.3%) of the 1,280 samples analyzed. The prevalence of antibodies was greater among males (7.8%) than among women (7%) and increased with age for both sexes, from 3% among subjects 15 to 24 years of age to 12% among subjects ≥65 years of age. Bivariate analysis of the sociodemographic and clinical variables showed an association between the prevalence of hepatitis E virus infection and minor surgery (OR, 1.96; 95% CI, 1.24 to 3.11), abdominal surgery (OR, 1.74; 95% CI, 1.12 to 2.73), and, for women, being uniparous or multiparous (OR, 2.84; 95% CI, 1.19 to 6.79). The multivariate analysis showed an association with minor surgery only (OR, 1.68; 95% CI, 1.03 to 2.70). In conclusion, anti-HEV antibodies were detected in 7.3% of the Catalan population. The seroprevalence of anti-HEV antibodies increased with age and was associated with previous minor surgery.