bluuebunny/crossref_metadata_2025_split huggingface dataset:
Variation in oxygen isotope fractionation during cellulose synthesis: intramolecular and biosynthetic effects
Authors: STERNBERG LEONEL , PINZON MARIA CAMILA , ANDERSON WILLIAM T. , JAHREN A. HOPE 
Published: July 2006

ABSTRACTThe oxygen isotopic composition of plant cellulose is commonly used for the interpretations of climate, ecophysiology and dendrochronology in both modern and palaeoenvironments. Further applications of this analytical tool depends on our in‐depth knowledge of the isotopic fractionations associated with the biochemical pathways leading to cellulose. Here, we test two important assumptions regarding isotopic effects resulting from the location of oxygen in the carbohydrate moiety and the biosynthetic pathway towards cellulose synthesis. We show that the oxygen isotopic fractionation of the oxygen attached to carbon 2 of the glucose moieties differs from the average fractionation of the oxygens attached to carbons 3–6 from cellulose by at least 9%, for cellulose synthesized within seedlings of two different species (Triticum aestivum L. and Ricinus communis L.). The fractionation for a given oxygen in cellulose synthesized by the Triticum seedlings, which have starch as their primary carbon source, is different than the corresponding fractionation in Ricinus seedlings, within which lipids are the primary carbon source. This observation shows that the biosynthetic pathway towards cellulose affects oxygen isotope partitioning, a fact heretofore undemonstrated. Our findings may explain the species‐dependent variability in the overall oxygen isotope fractionation during cellulose synthesis, and may provide much‐needed insight for palaeoclimate reconstruction using fossil cellulose.
Transgenic Medicago truncatula plants that accumulate proline display nitrogen‐fixing activity with enhanced tolerance to osmotic stress
Authors: VERDOY D. , COBA DE LA PEÑA T. , REDONDO F. J. , LUCAS M. M. , PUEYO J. J. 
Published: July 2006

ABSTRACTLegume root nodule nitrogen‐fixing activity is severely affected by osmotic stress. Proline accumulation has been shown to induce tolerance to salt stress, and transgenic plants over‐expressing Δ1‐pyrroline‐5‐carboxylate synthetase (P5CS), which accumulates high levels of proline, display enhanced osmotolerance. Here, we transformed the model legume Medicago truncatula with the P5CS gene from Vigna aconitifolia, and nodule activity was evaluated under osmotic stress in transgenic plants that showed high proline accumulation levels. Nitrogen fixation was significantly less affected by salt treatment compared to wild‐type (WT) plants. To our knowledge, this is the first time that transgenic legumes have been produced that display nitrogen‐fixing activity with enhanced tolerance to osmotic stress. We studied the expression of M. truncatula proline‐related endogenous genes M. truncatulaΔ1‐pyrroline‐5‐carboxylate synthetase 1 (MtP5CS1), M. truncatulaΔ1‐pyrroline‐5‐carboxylate synthetase 2 (MtP5CS2), M. truncatula ornithine δ‐aminotransferase (MtOAT), M. truncatula proline dehydrogenase (MtProDH) and a proline transporter gene in both WT and transgenic plants. Our results indicate that proline metabolism is finely regulated in response to osmotic stress in an organ‐specific manner. The transgenic model allowed us to analyse some of the biochemical and molecular mechanisms that are activated in the nodule in response to high salt conditions, and to ascertain the essential role of proline in the maintenance of nitrogen‐fixing activity under osmotic stress.
Rising under‐5 mortality in Africa: who bears the brunt?
Authors: Houweling Tanja A. J. , Kunst Anton E. , Moser Kath , Mackenbach Johan P. 
Published: July 2006

SummaryObjectives  To identify the socioeconomic and geographical groups in which the recent under‐5 mortality increase observed in several African countries was most pronounced, and to explore the contribution of a number of proximate determinants of under‐5 mortality.Methods  Time trends in under‐5 mortality were assessed with Cox Proportional Hazards regression analysis, using Demographic and Health Surveys data for Burkina Faso, Cameroon, Côte d'lvoire, Kenya and Zimbabwe for the late 1980s – 1990s. We tested for differences in time trends between socioeconomic and rural/urban subgroups, and described the inequalities in time trends in living conditions, malnutrition and health care use.Results  Under‐5 mortality increased substantially (ranging from 25% to 71% in 10 years) within the five countries. In Kenya, the increase was the largest among children born to less educated mothers (test for difference between educational groups: P = 0.074) and in rural areas (P = 0.090). In Cameroon, the increase was the largest among the higher educated (P = 0.013), and in Zimbabwe among the higher educated (P = 0.098) and in urban areas (P = 0.093). For Burkina Faso and Côte d'Ivoire, we did not observe statistically significant differences between educational and rural/urban subgroups. The decline in skilled delivery attendance in Zimbabwe and Kenya was similar among the less and higher educated. The decline in immunization coverage during the mid‐1990s in Zimbabwe was the largest in the group with the highest mortality increase, but in Kenya it was as large among the less and higher educated. Whereas in Kenya the increase in malnutrition was the largest in the group with the highest mortality increase, this was not the case in Zimbabwe.Conclusions  The recent increase in under‐5 mortality in some African countries was highly concentrated in specific population subgroups. Exactly which groups were most affected was highly variable. It cannot be assumed that lower socioeconomic groups are always most vulnerable. Strategies to halt the under‐5 mortality increase should be based on disaggregate information for individual countries.
Classifying dengue: a review of the difficulties in using the WHO case classification for dengue haemorrhagic fever
Authors: Bandyopadhyay Shibani , Lum Lucy C. S. , Kroeger Axel 
Published: July 2006

SummaryBackground  The current World Health Organisation (WHO) classification of dengue includes two distinct entities: dengue fever (DF) and dengue haemorrhagic fever (DHF)/dengue shock syndrome; it is largely based on pediatric cases in Southeast Asia. Dengue has extended to different tropical areas and older age groups. Variations from the original description of dengue manifestations are being reported.Objectives  To analyse the experience of clinicians in using the dengue case classification and identify challenges in applying the criteria in routine clinical practice.Method  Systematic literature review of post‐1975 English‐language publications on dengue classification.Results  Thirty‐seven papers were reviewed. Several studies had strictly applied all four WHO criteria in DHF cases; however, most clinicians reported difficulties in meeting all four criteria and used a modified classification. The positive tourniquet test representing the minimum requirement of a haemorrhagic manifestation did not distinguish between DHF and DF. In cases of DHF thrombocytopenia was observed in 8.6–96%, plasma leakage in 6–95% and haemorrhagic manifestations in 22–93%. The low sensitivity of classifying DHF could be due to failure to repeat the tests or physical examinations at the appropriate time, early intravenous fluid therapy, and lack of adequate resources in an epidemic situation and perhaps a considerable overlap of clinical manifestations in the different dengue entities.Conclusion  A prospective multi‐centre study across dengue endemic regions, age groups and the health care system is required which describes the clinical presentation of dengue including simple laboratory parameters in order to review and if necessary modify the current dengue classification.
Vesicular pemphigoid with circulating autoantibodies against 230‐kDa and 180‐kDa proteins, and additional autoantibodies against 97‐kDa and 45‐kDa proteins
Authors: Lai Feng‐Jie , Sheu Hamm‐Ming , Lee J. Yu‐Yun , Cheng Ching‐Li , Chen WenChieh 
Published: July 2006

The vesicular variant of bullous pemphigoid is a clinical entity in which the principal type of lesions are multiple small tense vesicles in a symmetric distribution, instead of the classical large, more randomly distributed large bullae. We describe a 62‐year‐old female who developed a vesicular variant of bullous pemphigoid, with intensely pruritic vesiculopapular eruptions and erythematous irregularly outlined patches confluent on the face, neck, trunk, extremities and oral mucosa. Direct immunofluorescence revealed a linear deposition of IgG and C3 at the basement membrane zone of the skin, and indirect immunofluorescence detected circulating IgG autoantibodies reacting with antigens located on the epidermal side of skin split with 1 M NaCl. Indirect immunogold electron microscopy revealed IgG deposition at the underneath membrane of the basal cells and in the lamina lucida. In addition to the 230‐kDa and 180‐kDa bullous pemphigoid antigen, immunoblot analysis also demonstrated the presence of IgG antibodies reactive with 97‐kDa and 45‐kDa protein. Treatment with systemic corticosteroid, minocycline and antihistamines plus topical steroid resulted in moderate improvement. A few vesicles, however, continued to appear intermittently during the past year of treatment.
Molecular analysis of vitiligo lesions reveals sporadic melanocyte survival
Authors: Gottschalk G. M. , Kidson S. H. 
Published: July 2006

AbstractVitiligo is a depigmenting disease of uncertain aetio‐pathogenesis. Although accepted as dogma, the question of whether melanocytes survive in vitiligo lesions has not been adequately resolved. Defining with greater accuracy the melanocyte status of lesions would contribute greatly towards the understanding of the etiology, progression and treatment of this disorder. We have therefore revisited this issue by carrying out a molecular screen for melanocytes in lesional skin using the sensitive and specific technique of reverse transcription PCR (RT‐PCR) followed by Southern blotting. Biopsies from vitiligo lesions and normal skin were obtained from 15 patients. The RT‐PCR was carried out using primers for tyrosinase and dopachrome tautomerase (DCT). To increase the sensitivity of detection, Southern‐blot analysis of all PCR products was conducted. Southern‐blot analysis indicated that three lesional samples were positive: one for tyrosinase, one for DCT, and one for both. Lesions yielding positive results had been present for between 2–5 years and were inactive, as defined by no disease progression within the last 3 months.Some vitiligo lesions showed evidence of melanocyte survival, even after some years. These results open the way for the possibility of using a range of melanocyte‐specific markers for molecular staging of lesional status by quantitative RT‐PCR. Such information would be extremely valuable for the appropriate selection and potential success of medical therapies.
Intraepidermal animal‐type melanoma
Authors: Punjabi S. , Wright C. , Teixeira F. , Stamp G. , Chu A. 
Published: July 2006

Animal‐type melanoma is a rare variant of melanoma in humans.1 Its name is derived from its histological appearance, which is similar to that described in melanomas occurring in white or gray horses.2 All tumors are dermally located, and characterized by a proliferation of deeply pigmented elongated or rounded cells, showing moderate atypia and a low mitotic rate. In some tumors, secondary infiltration of the epidermis has been noted. More than half of the patients are younger than 30 years, and prognosis seems to be much better than that expected for a superficial spreading or nodular melanoma of the same size. We report the first case of animal‐type melanoma in situ.
Epidemiological data and molecular characterization (mtDNA) of Sporothrix schenckii in 13 cases from Mexico
Authors: Arenas Roberto , Miller Daniel , Campos‐Macias Pablo 
Published: July 2006

AbstractBackground  Sporotrichosis is an endemic mycosis in Mexico and Central America.Objectives  To present epidemiological data and characterize molecular subtypes of 13 strains of Sporothrix schenckii, and to correlate clinical and epidemiologic presentation with subtypes.Methodology  Thirteen Mexican cases of sporotrichosis were identified, and mitochondrial DNA (mtDNA) from clinical isolates of S. schenckii were analyzed using RFLP Hae III. Molecular types 2, 3, 14, 28, and 29 were observed.Results  Clinical presentations and molecular types were consistent with established epidemiologic patterns for S. schenckii in this region.Conclusions  This investigation provides further evidence of the strong regional specificity of molecular types of this organism.
Facial peeling skin syndrome: A case report and a brief review
Authors: Janjua Shahbaz Ahmad , Hussain Ijaz , Khachemoune Amor 
Published: July 2006

AbstractPeeling skin syndrome is an extremely rare genodermatosis of possible autosomal recessive inheritance, characterized by asymptomatic spontaneous exfoliation of the stratum corneum at a subcorneal or intracorneal level. It usually presents at birth or appears later in early childhood. The condition may be generalized or localized. Here we describe a case of localized continual skin peeling limited to the facial skin in a 6‐month‐old infant, with two other members of the family affected with the same condition. A few cases of localized skin peeling limited to the acral surfaces have been described in the literature, but a familial case of localized skin peeling limited to the facial skin has not been described before. We believe that our patient represents a new subtype of peeling skin syndrome, limited to the skin of the face.
Allergy and Clinical Immunology Services in Europe*
Authors: Bonini S. , Ansotegui I.J. , Durham S. , Frew A.J. , Lötvall J. , Nekam K. , Popov T. , Dahl R. , Gayraud J. , Gerth van Wijk R. , Kontou‐Fili K. , Kowalski M. , Todo‐Bon A. , Wahn U. 
Published: July 2006

Allergology and Clinical Immunology (ACI) is an area of clinical medicine with a precise identity, relevant recent scientific achievements and well‐defined educational and professional needs.In spite of the high individual and socio‐economic impact of allergic diseases in Europe, the organization of ACI services is imperfect and varies among countries according to their health policies and priorities.In the firm belief of the role of ACI specialists in addressing clinical issues related to the involvement of the immune system in health and diseases—such as vaccination, immunodeficiencies, susceptibility and response to microbial agents, autoimmune and allergic diseases, immune aspects of transplantation and malignancies, in vivo and in vitro immunological tests, vaccinations, immuno‐modifiers—the European Academy of Allergology and Clinical Immunology appointed an ad hoc Task Force to produce standards for ACI Services in Europe.The resulting position paper should be used as a consulting reference for National Health Services as a necessary pre‐requisite for the free circulation to patients and health care professionals.
Honeybee (Apis mellifera ligustica) Response to Differences in Handling Time, Rewards and Flower Colours
Authors: Sanderson Charlotte E. , Orozco Benjamin S. , Hill Peggy S. M. , Wells Harrington 
Published: July 2006

AbstractFree flying honeybees were tested outdoors on blue–white and blue–yellow dimorphic artificial flower patches to examine the influence of reward difference, flower handling‐time difference and flower colour choice on foraging decisions. We employed different flower‐well depths to vary handling times (costs), and differences in sucrose molarity to vary reward quality. Tests were performed with 2 and 6 μl rewards to vary quantity. We show that when handling time is correlated with flower‐colour morphs on a pedicellate artificial flower patch, a honeybee's foraging behaviour is dependent on the flower colours used in the choice tests. This supports a honeybee foraging model where constraints are a significant factor in decision making. Bees visiting blue–yellow flower patches exhibited flower constancy to colour, where they restricted most visits to a single flower colour, some bees to blue and others to yellow, irrespective of handing time differences. When offered a choice of equally rewarding blue or white flowers, bees were not constrained by flower colour and chose to visit flowers with a lower handling time. When reward molarity varied with well depth between blue and white flowers, foragers chose shallow‐well flowers (short‐handling time) with a smaller net harvest rate over deep‐well flowers (long‐handling time) with a greater net harvest rate. Results using the blue–white dimorphic flower patch suggest that when foraging options simultaneously involve reward and handling‐time choices, honeybee forager behaviour is inconsistent with an absolute method of evaluating profit.
Black and White Colobus Monkey (Colobus guereza) Roars as a Source of Both Honest and Exaggerated Information About Body Mass
Authors: Harris Tara R. , Fitch W. T. , Goldstein Louis M. , Fashing Peter J. 
Published: July 2006

AbstractFormant dispersion, the average spacing, in Hz, between the resonant frequencies of a vocalization, has been predicted to provide honest information about signaler body size. Previous descriptions of black and white colobus monkey (Colobus guereza, “guereza”) roars, however, suggest a formant dispersion that is far lower than expected for an animal its size, and could effectively exaggerate its body size. Nonetheless, recent research on red deer shows that even when the formant positions of vocalizations effectively exaggerate body size, they may still provide honest cues within a species. We investigate whether the frequency bands observed in the spectrograms of guereza roars represent formants, and whether roar formant dispersion and/or individual formants provide honest information about body size (specifically, body mass) relative to conspecifics, although perhaps not relative to other species. We document coordinated vertical movements in the frequency bands of guereza roars and show that these bands move independently of fundamental frequency, indicating that they represent formants. We show, for captive adult male guerezas, that signaler body mass significantly predicts roar formant dispersion, even for randomly selected calls. Body mass also predicts formants 2 and 3, but the relationships are not as strong as with formant dispersion. Our roar formant dispersion calculations predict a vocal tract length of approx. 29 cm, but anatomically determined guereza vocal tract length is much smaller: approx. 7–8 cm. Videotaped roars revealed no laryngeal movement during roars, but rather inflation of the subhyoid air sac. We measured the volume of this air sac (approx. 10 cm3) and speculate that it may function in roars to exaggerate body size, relative to other species.
Thermal requirements and phenology of the Eucalyptus snout beetle Gonipterus scutellatus Gyllenhal
Authors: Santolamazza‐Carbone S. , Rodríguez‐Illamola A. , Cordero Rivera A. 
Published: July 2006

Abstract:  Laboratory experiments and field surveys were carried out to study the thermal requirements and phenology of the Eucalyptus snout beetle Gonipterus scutellatus (Curculionidae) and its parasitoid, Anaphes nitens (Mymaridae). Developmental times were recorded for G. scutellatus life stages: egg to first instar larva, first instar to pre‐pupal larva, prepupae to adults and the complete life cycle. Experiments were performed in temperature‐controlled chambers maintained at 10, 15, 20, 25 and 30°C with a photoperiod of 11 : 13 h of light : darkness and 50–60% RH. To calculate the minimum threshold temperature of the parasitoid, parasitized egg capsules were kept under similar conditions. During 1998 and 1999 we studied the phenology and the day‐degree (DD) accumulation of G. scutellatus and its parasitoid in plots of Eucalyptus globulus at six different sites in NW Spain. Every 2 weeks, the numbers of snout beetle adults and egg capsules were counted in each plot. The rate of parasitism was estimated by collecting 90 egg capsules from each plot on each sampling date. We recorded the temperatures in each plot to test whether differences in temperature alone could account for the phenology of this snout beetle. To complete a full life cycle from egg to adult, the weevil required a mean of 1119.83 ± 20.59 DD above a base temperature of 6.11°C. The parasitoid had a base temperature of 5.09°C and needed 318.16 DD to complete a life cycle. Our model indicated that three generations of snout beetle could develop each year, corresponding to peaks of snout beetle numbers in the field in March–April, June–July and November. In some years only one generation of G. scutellatus was recorded due probably to the effectiveness of the parasitoid. Differences in numbers of adults and egg capsule were recorded between neighbouring ‘coastal plots’ and between neighbouring ‘inland plots’. Hence, climate alone does not appear to explain the phenology of G. scutellatus.
The Identification of a Limited Number of Vegetative Compatibility Groups within Isolates of Sclerotinia homoeocarpa Infecting Poa spp. and Agrostis palustris from Temperate Climates
Authors: Mitkowski N. A. , Colucci S. 
Published: July 2006

Abstract Sclerotinia homoeocarpa is responsible for causing significant damage on a wide variety of different grass species. Because it is an asexual fungus, the study of its population structure can be difficult. Previous research has determined that S. homoeocapra has anywhere from three to 20 vegetative compatibility groups (VCGs) within localized geographic ranges in the United States. However, a survey of a large geographic area has yet to be undertaken. The present study examined 25 isolates of S. homoeocarpa from the United Kingdom, Rhode Island, Massachusetts, Connecticut, Ohio, Illinois and Oregon. Among the 25 isolates, eight VCGs were identified. Other researchers have reported that there are seven VCGs in temperate North America on amenity turfgrasses. It is still unclear how this relates to the pathogen's VCG diversity in subtropical and tropical climates.
Evaluation of Resistance to Race 3, Biovar 2 of Ralstonia solanacearum in Tomato Germplasm
Authors: Carmeille A. , Prior P. , Kodja H. , Chiroleu F. , Luisetti J. , Besse P. 
Published: July 2006

AbstractSources of resistance to tropical race 1 strains of Ralstonia solanacearum, the causative agent of bacterial wilt, have been identified in the tomato germplasm. Till now, no experimental data are available on Lycopersicon spp. (now Solanum spp.) sources for resistance to temperate race 3, biovar 2 strains. Eighty‐two accessions belonging to different Lycopersicon spp. were evaluated for resistance to a race 3 strain endemic to Réunion Island. Evaluation was conducted in growth chambers, and included the Lycopersicon esculentum cv. Roma as susceptible control. No immunity or complete resistance was observed in any accession tested under our experimental conditions. Therefore, race 3 strain was demonstrated to be highly pathogenic on all the Lycopersicon accessions tested. Partial resistance was significantly detected in only one accession belonging to the species Lycopersicon peruvianum, and one L. esculentum var. cerasiforme tomato line. Five other genotypes from the species L. esculentum, Lycopersicon hirsutum and L. peruvianum were noteworthy. The Hawaii 7996 line represented the best source of partial resistance to race 3 with 52% of wilting. It can therefore be used as a starting point for introducing resistance to bacterial wilt caused by R. solanacearum race 3 in tomato and studying its genetic control.