bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pregnancy‐induced hypertension and infant mortality: roles of birthweight centiles and gestational age
Authors: Chen XK , Wen SW , Smith G , Yang Q , Walker M 
Published: December 2006

Objective  To assess the effect of pregnancy‐induced hypertension (PIH) on infant mortality in different birthweight centiles (small for gestational age [SGA], appropriate for gestational age [AGA], and large for gestational age [LGA]) and gestational ages (early preterm, late preterm, and full term).Design  Retrospective cohort study.Setting  Linked birth and infant death data set of USA between 1995 and 2000.Population  A total of 17 464 560 eligible liveborn singleton births delivered after 20th gestational week.Methods  Multivariate logistic regression models were applied to evaluate the association between PIH and infant mortality, with adjustment of potential confounders stratified by birthweight centiles and gestational age.Main outcome measure  Infant death (0–364 days) and its three components: early neonatal death (0–6 days), late neonatal death (7–27 days), and postneonatal death (28–364 days).Results  PIH was associated with decreased risks of infant mortality, early neonatal mortality, and late neonatal mortality in both preterm and term SGA births, and PIH was associated with lower postneonatal mortality in preterm SGA births. PIH was associated with decreased risks of infant mortality, early neonatal mortality, late neonatal mortality and postneonatal mortality in preterm AGA births. Decreased risk of infant mortality and early neonatal mortality was associated with PIH in early preterm LGA births.Conclusions  The association between PIH and infant mortality varies depending on different birthweight centiles, gestational age, and age at death. PIH is associated with a decreased risk of infant mortality in SGA births, preterm AGA births, and early preterm LGA births.
Allopurinol, oxidative stress and intestinal permeability in patients with cirrhosis: an open‐label pilot study
Authors: Spahr Laurent , Bresson‐Hadni Solange , Amann Pauline , Kern Ilse , Golaz Olivier , Frossard Jean‐Louis , Hadengue Antoine 
Published: December 2006

AbstractBackground: Cirrhosis is associated with intestinal barrier failure, related in part to enterocytes oxidative damage via xanthine oxidase overactivity. Experimentally, allopurinol, a xanthine oxidase inhibitor, reduces enterocytes' damage and bacterial translocation.Aim: To assess the short‐term effects of allopurinol on intestinal permeability, oxidative stress and endotoxin‐dependent cytokines in patients with cirrhosis.Methods: Nineteen patients with cirrhosis, in a stable condition (age: 56 years; Child A/B/C: 6/7/6; ascites: 12; alcoholic cirrhosis: 16/19; abstinence >2 weeks), were included. At baseline and day 10 of allopurinol 400 mg/day, intestinal permeability [lactulose/mannitol (Lac/Man) ratio test], oxidative stress (serum malondialdehyde), as well as TNF‐soluble receptor‐1, IL‐6 and lipopolysaccharide‐binding protein (which reflects exposition to endotoxin) were measured.Results: Malondialdehyde decreased significantly (−23%, P<0.05), whereas no effects were seen on intestinal permeability and the endotoxin‐associated systemic inflammatory response. At baseline, portal pressure correlated to the Lac/Man ratio (r=0.55, P<0.02). At day 10, changes in malondialdehyde correlated to changes in the Lac/Man ratio (r=0.51, P<0.05).Conclusions: A 10‐day course of allopurinol in patients with cirrhosis is associated with a significant reduction in oxidative stress but no effect on intestinal permeability and inflammatory markers. Whether intestinal damage in cirrhosis can be accessible to antioxidant therapy requires further study.
Thiopurine S‐methyltransferase gene polymorphism in Japanese patients with autoimmune liver diseases
Authors: Tamori Akihiro , Shinzaki Mayumi , Kosaka Saori , Hayashi Takehiro , Iwai Shuji , Enomoto Masaru , Habu Daiki , Sakaguchi Hiroki , Kawada Norifumi , Hino Masayuki , Shiomi Susumu , Nishiguchi Shuhei 
Published: December 2006

AbstractBackground and aim: Thiopurine S‐methyltransferase (TPMT) genotypes or phenotypes may be a predictive factor for azathioprine‐induced toxicities. We investigated the genotypic status of TPMT to evaluate the risk of azathioprine‐related adverse effects in Japanese patients with different liver diseases, including autoimmune hepatitis (AIH).Methods: 49 patients with AIH, 67 with primary biliary cirrhosis (PBC), and 120 with hepatitis C virus (HCV) were examined. TPMT genotypes were determined by PCR‐restriction fragment length polymorphism‐based assays.Results: The distribution of TPMT genotypes was 90% TPMT*1/TPMT*1, 8% TPMT*1/TPMT*3C, and 2% TPMT*3C/TPMT*3C in AIH, and 94% TPMT*1/TPMT*1, 4.5% TPMT*1/TPMT*3C, and 1.5% TPMT*3C/TPMT*3C in PBC. All except 1 patient with HCV had the TPMT*1/TPMT*1 genotype. Severe myelosuppression occurred in two of nine patients with AIH who received azathioprine, one of whom was homozygous for TPMT*3C.Conclusions: TPMT*3C variants are more frequent in patients with AIH or PBC than in patients with viral hepatitis or healthy volunteers in Japan. Pharmacogenetic screening for TPMT polymorphisms before commencing azathioprine therapy may help to prevent severe hematotoxicity in patients with TPMT deficiency.
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

AbstractDeforested 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

AbstractPinus 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

AbstractA 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

AbstractPrescribed 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

Abstract 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

Abstract 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

AbstractNative 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

Abstract 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

AbstractForest 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.
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.