bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prevalence and risk factors of asthma and allergic diseases among schoolchildren in Bolu, Turkey
Authors: Talay Fahrettin , Kurt Bahar , Tug Tuncer , Yilmaz Fahrettin , Goksugur Nadir 
Published: March 2008

AbstractAim: In this study we aimed to detect the prevalence and risk factors of asthma and allergic diseases in children aged between 7 and 14 years old at rural and urban areas of Bolu, Turkey.Methods: Questionnaire of International Study of Asthma and Allergies in Childhood (ISAAC) phase one and questionnaire including questions about family, demographic, socio‐economic characteristics of children were applied to 931 schoolchildren who were selected by randomized sampling.Results: In children, the prevalence of diseases and symptoms were as follows: wheeze ever: 15.5%, asthma: 5.6%, nasal symptoms ever: 41.4%, allergic rhinitis: 23.2%, itchy rash ever: 5.9% and eczema: 5.0%. In multivariate regression analysis, presence of allergic disease in the family was risk factor for wheezing (OR = 1.74, 95% CI = 1.19–2.76), asthma (OR = 2.19, CI = 1.06–4.52), allergic rhinitis (OR = 2.68, CI = 1.80–3.98) and eczema (OR = 2.33, CI = 1.17–4.65); living in shanties was risk factor for allergic rhinitis (OR = 5.26, CI = 2.1–13.16); a monthly income below $300 was risk factor for asthma (OR = 2.54, CI = 1.06–6.08).Conclusion: It was detected that the prevalence of allergic rhinitis and its symptoms was more common in schoolchildren living in Bolu. Presence of allergic disease in fathers or mothers and low socio‐economic level increase the risk of asthma and other allergic diseases in children.
Ethics ain't easy: do we need simple rules for complicated ethical decisions?
Authors: Janvier Annie , Barrington Keith J. , Aziz Khalid , Lantos John 
Published: March 2008

AbstractBackground: Recommendations from national bodies regarding extremely preterm infants have focussed almost exclusively on thresholds for intervention based upon estimated gestational age (GA) alone.Methods: We reviewed policy statements that address active intervention for newborn infants and compare them with those that are available for older patients. We reviewed research, examining attitudes towards preterm infants, uncertainties in GA assessment and other factors important in determining prognosis at the time of birth.Results: Policy statements regarding active care of very preterm infants treat this population differently from others in morally significant ways – without rationalizing this discrepancy. Extremely preterm infants are devalued in medical and lay opinion compared to older individuals with similar outcomes. Uncertainty in GA estimates often covers a range with vastly differing prognoses. Sex, birth weight, inborn‐outborn status and use of antenatal steroids are vitally important in prognosis, but clinical findings in the delivery room are not. Most policy statements fail to account for these factors.Conclusion: Simplistic policies based on GA alone should be avoided. Decision making for extremely preterm infants should recognize that they are each unique and must be individualized, taking into account all relevant prognostic factors and the values and wishes of the families.
Nesting Success of Costa Rican Lowland Rain Forest Birds in Response to Edge and Isolation Effects
Authors: Young Bruce E. , Sherry Thomas W. , Sigel Bryan J. , Woltmann Stefan 
Published: March 2008

ABSTRACTAlthough open‐cup nesting birds generally face increased risk of nest depredation from forest edge predators and brood parasites in fragmented temperate landscapes, little information exists to assess such risks in tropical birds. We compared nesting success of real birds' nests in large and small forest fragments to a control site in Caribbean lowland wet forest of Costa Rica. Pooling across species, nesting success was significantly greater in unfragmented forest than in either small, isolated fragments or the La Selva Biological Reserve, which is at the tip of a forest ‘peninsula’ embedded in a largely deforested landscape. Nesting success in isolated fragments did not vary according to distance from edge, suggesting that predators in fragments act throughout these forest patches. The case for increased nest predation as a plausible mechanism to explain the documented decline of forest interior bird populations in this fragmented tropical landscape is enhanced by a simple demographic model that suggests nesting success is likely too low to maintain populations at La Selva and in the fragments. The fact that the large (> 1000 ha) La Selva forest reserve is experiencing nest predation rates similar to those in much smaller fragments is cause for concern. Our results make a strong case for additional studies to document the identities of nest predators in both fragmented and unfragmented forests in such tropical forest landscapes.
Influence of Drought and Shade on Seedling Growth of Native and Invasive Trees in the Seychelles
Authors: Schumacher Eva , Kueffer Christoph , Tobler Monika , Gmür Veronika , Edwards Peter J. , Dietz Hansjörg 
Published: March 2008

ABSTRACTWe studied the growth of seedlings of native and invasive tree species from secondary tropical forests on Mahé (Seychelles). We were interested in whether native or invasive species are more drought‐tolerant, and therefore conducted a garden (pot) experiment comparing the growth of seedlings of five native and five invasive tree species under different light (7% and 60% transmittance) and water (natural and repeated drought stress) conditions. Differences in the responses of native and invasive species to these treatments were small. In both groups, mean relative growth rates were reduced only slightly by intermittent drought that caused wilting of leaves. However, invasive species produced clearly thinner leaves (high specific leaf area, SLA) and more root biomass than native species under high light, while these differences were small under low light. Native species performed better than invasive species under low light with low water availability. It appears that high phenotypic plasticity allows some fast‐growing invasive species to cope with water stress by adjusting the relative allocation of resources to aboveground and belowground structures under high light, while this strategy is not effective when both light and water resources are limiting. We conclude that water stress may reduce the invasibility of shaded habitats by fast‐growing invasive species, while water stress in unshaded habitats may have less effect on invasive species than previously recognized.
Detecting Altitudinal Migration Events in Neotropical Birds Using Stable Isotopes
Authors: Fraser Kevin C. , Kurt Kyser T. , Ratcliffe Laurene M. 
Published: March 2008

ABSTRACTWe evaluated the utility of stable‐hydrogen isotope ratios in tropical bird tissues for detecting altitudinal migration events. Our results identified two of five species as altitudinal migrants in Nicaragua. This approach may circumvent the current limitations of mark–recapture techniques and enhance our ability to study this poorly characterized behavior.
Root‐fed Salicylic Acid in Grape Involves the Response Caused by Aboveground High Temperature
Authors: Liu Hong‐Tao , Liu Yue‐Ping , Huang Wei‐Dong 
Published: March 2008

Abstract In order to investigate the transportation and distribution of salicylic acid (SA) from root to aboveground tissues in response to high temperature, the roots of grape plant were fed with 14C‐SA before high temperature treatment. Radioactivity results showed that progressive increase in SA transportation from root to aboveground as compared with the control varied exactly with the heat treatment time. Radioactivity results of leaves at different stem heights indicated that the increase in SA amount at the top and middle leaves during the early period was most significant in comparison with the bottom leaves. The up‐transportation of SA from root to aboveground tissues was dependent on xylem rather than phloem. Auto‐radiographs of whole grape plants strongly approved the conclusions drawn above. Root‐derived SA was believed to be a fundamental source in response to aboveground high temperature.
Effects of Light on the Growth and Clonal Reproduction of Ligularia virgaurea
Authors: Wang Man‐Tang , Zhao Zhi‐Gang , Du Guo‐Zhen , He Yan‐Long 
Published: March 2008

Abstract
Ligularia virgaurea is a perennial herb that is widely distributed in the alpine meadow on the eastern Qinghai‐Tibet plateau. We investigated the patterns of growth and reproduction of L. virgaurea under two contrasting levels of light conditions for two continuous growing seasons. Our results showed that the light effects on the maximum relative growth rate, the shoot weight ratio and the root weight ratio differed between the two growing seasons. L. virgaurea reproduced initially through rhizome in the second growing season, rather than sexual reproduction. The proportion of genets with clonal reproduction decreased under shaded conditions. A minimum genet size should be attained for clonal reproduction to begin under the shaded conditions. There was a positive linear relationship between clonal reproduction and genet size. Light level affected the allocation of total biomass to clonal structures, with less allocation under the full natural irradiance than under the shaded conditions. There seemed to be a trade‐off between vegetative growth and clonal reproduction under the full natural irradiance, in terms of smaller relative growth rates of genets with clonal reproduction than those without clonal reproduction. L. virgaurea emphasized clonal reproduction under the full natural irradiance, while the plant emphasized vegetative growth under the shaded conditions.
The transition from pulpitis to periapical periodontitis in dogs’ teeth
Authors: Kovačević Maja , Tamarut Tomislav , Jonjić Nives , Braut Alen , Kovačević Miljenko 
Published: March 2008

AbstractThe purpose of the study was to histologically analyse transition from pulpitis to periapical periodontitis on dog's teeth. Pulps of mandibular premolars (37 roots) were exposed using a low‐speed handpiece. Teeth were left open to the oral environment for 20, 35, 50 and 65 days. After the experimental period animals were sacrificed. Undemineralised teeth with surrounding bone, embedded in methylmetacrylate, were prepared for standard histological analysis. All teeth with pulpitis (five roots), regardless of the experimental period, had acute serose periapical periodontitis. All teeth (15 roots) with partial pulp necrosis had subacute periapical periodontitis. Teeth with complete pulp necrosis (19 roots) had chronic periapical periodontitis and in one case suppurative apical periodontitis. The condition of the pulp correlates with the histopathological findings of periapical tissue in the open types of pulp infection. Acute periapical periodontitis begins during pulpitis and can occur before 20 days of pulp exposure in the dog.
Non‐surgical management of infected type III dens invaginatus with vital surrounding pulp using contemporary endodontic techniques
Authors: John Vijay 
Published: March 2008

AbstractThis paper reports on the conservative non‐surgical endodontic management of an upper right lateral incisor diagnosed with infected dens invaginatus (Oehlers’ type III) and associated acute apical abscess, while maintaining vitality of the surrounding pulp. The use of contemporary endodontic techniques in the diagnosis, treatment planning and management of the case is highlighted.
RESEARCH ARTICLE: Myelin Abnormalities without Oligodendrocyte Loss in Periventricular Leukomalacia
Authors: Billiards Saraid S. , Haynes Robin L. , Folkerth Rebecca D. , Borenstein Natalia S. , Trachtenberg Felicia L. , Rowitch David H. , Ligon Keith L. , Volpe Joseph J. , Kinney Hannah C. 
Published: March 2008

AbstractThe cellular basis of myelin deficits detected by neuroimaging in long‐term survivors of periventricular leukomalacia (PVL) is poorly understood. We tested the hypothesis that oligodendrocyte lineage (OL) cell density is reduced in PVL, thereby contributing to subsequent myelin deficits. Using computer‐based methods, we determined OL cell density in sections from 18 PVL and 18 age‐adjusted control cases, immunostained with the OL‐lineage marker Olig2. Myelination was assessed with myelin basic protein (MBP) immunostaining. We found no significant difference between PVL and control cases in Olig2 cell density in the periventricular or intragyral white matter. We did find, however, a significant increase in Olig2 cell density at the necrotic foci, compared with distant areas. Although no significant difference was found in the degree of MBP immunostaining, we observed qualitative abnormalities of MBP immunostaining in both the diffuse and necrotic components of PVL. Abnormal MBP immunostaining in PVL despite preserved Olig2 cell density may be secondary to arrested OL maturation, damage to OL processes, and/or impaired axonal‐OL signaling. OL migration toward the “core” of injury may occur to replenish OL cell number. This study provides new insight into the cellular basis of the myelin deficits observed in survivors of PVL.
RESEARCH ARTICLE: An Orthotopic Skull Base Model of Malignant Meningioma
Authors: Baia Gilson S. , Dinca Eduard B. , Ozawa Tomoko , Kimura Edna T. , McDermott Michael W. , James C. David , VandenBerg Scott R. , Lal Anita 
Published: March 2008

AbstractMeningioma tumor growth involves the subarachnoid space that contains the cerebrospinal fluid. Modeling tumor growth in this microenvironment has been associated with widespread leptomeningeal dissemination, which is uncharacteristic of human meningiomas. Consequently, survival times and tumor properties are varied, limiting their utility in testing experimental therapies. We report the development and characterization of a reproducible orthotopic skull‐base meningioma model in athymic mice using the IOMM‐Lee cell line. Localized tumor growth was obtained by using optimal cell densities and matrigel as the implantation medium. Survival times were within a narrow range of 17–21 days. The xenografts grew locally compressing surrounding brain tissue. These tumors had histopathologic characteristics of anaplastic meningiomas including high cellularity, nuclear pleomorphism, cellular pattern loss, necrosis and conspicuous mitosis. Similar to human meningiomas, considerable invasion of the dura and skull and some invasion of adjacent brain along perivascular tracts were observed. The pattern of hypoxia was also similar to human malignant meningiomas. We use bioluminescent imaging to non‐invasively monitor the growth of the xenografts and determine the survival benefit from temozolomide treatment. Thus, we describe a malignant meningioma model system that will be useful for investigating the biology of meningiomas and for preclinical assessment of therapeutic agents.
RESEARCH ARTICLE: Neurogenesis Impairment and Increased Cell Death Reduce Total Neuron Number in the Hippocampal Region of Fetuses with Down Syndrome
Authors: Guidi Sandra , Bonasoni Paola , Ceccarelli Claudio , Santini Donatella , Gualtieri Fabio , Ciani Elisabetta , Bartesaghi Renata 
Published: March 2008

AbstractWe previously obtained evidence for reduced cell proliferation in the dentate gyrus (DG) of fetuses with Down syndrome (DS), suggesting that the hippocampal hypoplasia seen in adulthood may be caused by defective early neuron production. The goal of this study was to establish whether DS fetuses (17–21 weeks of gestation) exhibit reduction in total cell number in the DG, hippocampus and parahippocampal gyrus (PHG). Volumes of the cellular layers and cell number were estimated with Cavalieri's principle and the optical fractionator method, respectively. We found that in DS fetuses all investigated structures had a reduced volume and cell number. Analysis of cell phenotype showed that DS fetuses had a higher percentage of cells with astrocytic phenotype but a smaller percentage of cells with neuronal phenotype. Immunohistochemistry for Ki‐67, a marker of cycling cells, showed that DS fetuses had less proliferating cells in the germinal zones of the hippocampus and PHG. We additionally found that in the hippocampal region of DS fetuses there was a higher incidence of apoptotic cell death. Results show reduced neuron number in the DS hippocampal region and suggest that this defect is caused by disruption of neurogenesis and apoptosis, two fundamental processes underlying brain building.
SYMPOSIUM: Clearance of Aβ from the Brain in Alzheimer's Disease: Perivascular Drainage of Amyloid‐β Peptides from the Brain and Its Failure in Cerebral Amyloid Angiopathy and Alzheimer's Disease
Authors: Weller Roy O. , Subash Malavika , Preston Stephen D. , Mazanti Ingrid , Carare Roxana O. 
Published: March 2008

AbstractAlzheimer's disease is the commonest dementia. One major characteristic of its pathology is accumulation of amyloid‐β (Aβ) as insoluble deposits in brain parenchyma and in blood vessel walls [cerebral amyloid angiopathy (CAA)]. The distribution of Aβ deposits in the basement membranes of cerebral capillaries and arteries corresponds to the perivascular drainage pathways by which interstitial fluid (ISF) and solutes are eliminated from the brain—effectively the lymphatic drainage of the brain. Theoretical models suggest that vessel pulsations supply the motive force for perivascular drainage of ISF and solutes. As arteries stiffen with age, the amplitude of pulsations is reduced and insoluble Aβ is deposited in ISF drainage pathways as CAA, thus, further impeding the drainage of soluble Aβ. Failure of perivascular drainage of Aβ and deposition of Aβ in the walls of arteries has two major consequences: (i) intracerebral hemorrhage associated with rupture of Aβ‐laden arteries in CAA; and (ii) Alzheimer's disease in which failure of elimination of ISF, Aβ and other soluble metabolites from the brain alters homeostasis and the neuronal environment resulting in cognitive decline and dementia. Therapeutic strategies that improve elimination of Aβ and other soluble metabolites from the brain may prevent cognitive decline in Alzheimer's disease.
SYMPOSIUM: Clearance of Aβ from the Brain in Alzheimer' Disease: The Role of the Immune System in Clearance of Aβ from the Brain
Authors: Boche Delphine , Nicoll James A.R. 
Published: March 2008

AbstractIn Alzheimer's disease (AD), there is abnormal accumulation of Aβ and tau proteins in the brain. There is an associated immunological response, but it is still unclear whether this is beneficial or harmful. Inflammation in AD, specifically in the form of microglial activation, has, for many years, been considered to contribute to disease progression. However, two types of evidence suggest that it may be appropriate to revise this view: first, the disappointing results of prospective clinical trials of anti‐inflammatory agents and, second, the observation that microglia can clear plaques in AD following Aβ immunization. Although Aβ immunization alters AD pathology, there is limited evidence so far of benefit to cognitive function. Immunization against microorganisms is almost always used as a method of disease prevention rather than to treat a disease process that has already started. In animal models, immunotherapy at an early age can protect against Aβ accumulation and it will be interesting to see if this can usefully be applied to humans to prevent AD.
Topical Treatment with OGG1 Enzyme Affects UVB‐induced Skin Carcinogenesis†
Authors: Wulff Brian C. , Schick Jonathan S. , Thomas‐Ahner Jennifer M. , Kusewitt Donna F. , Yarosh Daniel B. , Oberyszyn Tatiana M. 
Published: March 2008

AbstractNonmelanoma skin cancer resulting from UVB exposure is a large and growing problem in the United States. Production of reactive oxygen species (ROS) during the UVB‐induced inflammatory response results in the formation of oxidative DNA adducts such as 8‐hydroxy‐2‐deoxyguanine (8‐oxo‐dG), which have been shown to contribute to the development of this cancer. The 8‐oxoguanine DNA glycosylase (OGG1) enzyme repairs 8‐oxo‐dG adducts, suggesting that enhancing its activity in the skin might increase 8‐oxo‐dG repair thus preventing skin cancer development. We therefore used the SKH‐1 murine model to examine the effect of topically applied OGG1 on UVB‐induced skin cancer development. Mice were exposed three times weekly to UVB followed immediately by topical treatment with a formulation of liposome‐encapsulated OGG1 enzyme for 25 weeks. While this treatment did not affect UVB‐induced tumor multiplicity, it did reduce tumor size and dramatically reduced tumor progression, as indicated by tumor grade. These results suggest that oxidative DNA damage contributes to the progression of UVB‐induced skin tumors and that a topical formulation containing OGG1, perhaps in conjunction with other DNA repair enzymes such as T4 endonuclease V, could be used in populations at high risk for skin cancer development.
Cyclo‐oxygenase‐2 Plays a Critical Role in UV‐induced Skin Carcinogenesis†
Authors: Rundhaug Joyce E. , Fischer Susan M. 
Published: March 2008

AbstractBesides induction of DNA damage and p53 mutations, chronic exposure to UV irradiation leads to the constitutive up‐regulation of cyclo‐oxygenase‐2 (COX‐2) expression and to increased production of its primary product in skin, prostaglandin E2 (PGE2). COX‐2 has also been shown to be constitutively overexpressed in mouse, as well as human, UV‐induced skin cancers and premalignant lesions. UV exposure results in ligand‐independent activation of the epidermal growth factor receptor and subsequent activation of mitogen‐activated protein kinase and phosphatidylinositol 3‐kinase/Akt pathways leading to transcriptional activation of the COX‐2 gene. Use of COX‐2‐specific inhibitors and genetic manipulation of COX‐2 expression have demonstrated that UV induction of COX‐2 in the skin contributes to the induction of epidermal hyperplasia, edema, inflammation, and counters the induction of apoptosis after UV exposure. Likewise, inhibition of COX‐2 activity or reduced expression in COX‐2 knockout mice resulted in significantly reduced UV‐induced tumorigenesis, while overexpression of COX‐2 in transgenic mice enhanced UV‐induced tumor development. A combination of signaling from the PGE2 EP1, EP2 and/or EP4 receptors mediates the effects of COX‐2 overexpression. These studies demonstrate the crucial role of COX‐2 in the development of UV‐related nonmelanoma skin cancers.
Hypothesis—Ultraviolet‐B Irradiance and Vitamin D Reduce the Risk of Viral Infections and thus Their Sequelae, Including Autoimmune Diseases and some Cancers†
Authors: Grant William B. 
Published: March 2008

AbstractMany viral infections reach clinical significance in winter, when it is cold, relative humidity is lowest and vitamin D production from solar ultraviolet‐B irradiation is at its nadir. Several autoimmune diseases, such as multiple sclerosis, type 1 diabetes mellitus and asthma, are linked to viral infections. Vitamin D, through induction of cathelicidin, which effectively combats both bacterial and viral infections, may reduce the risk of several autoimmune diseases and cancers by reducing the development of viral infections. Some types of cancer are also linked to viral infections. The cancers with seemingly important risk from viral infections important in winter, based on correlations with increasing latitude in the United States, an index of wintertime solar ultraviolet‐B dose and vitamin D, are bladder, prostate, testicular and thyroid cancer, Hodgkin’s and non‐Hodgkin’s lymphoma, and, perhaps, gastric cancer. The evidence examined includes the role of viruses in the etiology of these diseases, the geographic and seasonal variation of these diseases, and the time of life when vitamin D is effective in reducing the risk of disease. In general, the evidence supports the hypothesis. However, further work is required to evaluate this hypothesis.