bluuebunny/crossref_metadata_2025_split huggingface dataset:
PHOSPHATE UPTAKE AND ANATOMY OF UNTHICKENED AND SECONDARILY THICKENED ADVENTITIOUS ROOTS OF FIELD‐GROWN WHITE CLOVER (TRIFOLIUM REPENS L.)
Authors: HAY M. J. M. , DUNLOP JAMES , HOPCROFT D. H. 
Published: May 2006

SummaryThis study reports on the uptake of phosphate by, and the anatomy of, unthickened roots of primary structure and secondarily thickened roots of intact white clover (Trifolium repens L.) plants which were washed from turves from grazed pasture. Phosphate uptake was measured over 24 h by supplying 6 mm root segments with [32P] labelled nutrient solution. The total quantity of labelled phosphate translocated from the treated segment was 10 times greater in unthickened root (405.1 pmol) than in secondarily thickened root (40.7 pmol). A higher proportion of accumulated phosphate was translocated from unthickened than from thickened roots.Features of unthickened primary root structure including presence of thin‐walled, intact epidermal and cortical cells, a lack of suberization except for Casparian bands in the endodermis, heavy infections of endomycorrhiza and presence of root hairs, were consistent with an ability to absorb and transport ions rapidly. Several features of secondarily thickened roots indicated these to be less adapted to absorb and transport ions rapidly including invasion of the outermost layers of cells by bacteria, disintegration of cells, and suberin lamellae encasing cells of the phellem. Suberization of the periderm was thought to reduce rate of phosphate movement into the root apoplast. Roots which were secondarily thickened were not infected by endomycorrhiza and had no root hairs.
TOLERANCE OF SODIUM CHLORIDE AND ITS GENETIC BASIS IN NATURAL POPULATIONS OF FOUR GRASS SPECIES
Authors: ASHRAF M. , McNEILLY T. , BRADSHAW A. D. 
Published: May 2006

SummaryTolerance to sodium chloride in solution culture and its genetic basis has been assessed for populations of Festuca rubra L., Holcus lanatus L., Agrostis stolonifera L., and Dactylis glomerata L. from salt marsh, spray zone, and inland habitats. Two populations of F. rubra from salt marshes and one population of A. stolonifera from a spray zone showed significant NaCl tolerance. However, in the main, responses of populations to increasing NaCl in the rooting medium showed little relationship with electrical conductivity or Na content of the soil. Narrow‐sense heritability estimates were high for all populations, except for one F. rubra population from a salt marsh and the population of A. stolonifera from a spray zone. Broad‐sense heritabilities were high for all populations suggesting high genetic components for variation in NaCl tolerance.
DIFFERENTIAL SENSITIVITY OF DUCKWEEDS (LEMNACEAE) TO SULPHITE
Authors: TAKEMOTO B. K. , NOBLE R. D. , HARRINGTON H. M. 
Published: May 2006

SummaryThe thiol contents and emissions of hydrogen sulphide (H2S) of duckweeds (Lemnaceae) differentially sensitive to sulphite enrichment were studied, at two levels of irradiance. The objectives were to examine the relationship of selected parameters of sulphite metabolism to sulphite sensitivity, and the role of irradiance in modifying the metabolic effects of sulphite.Under low irradiance, thiol contents were increased 30 to 40% by sulphite in all three duckweeds examined. Hydrogen sulphide was emitted by all three species, but emission rates in Lemna valdiviana, which is sulphite‐tolerant, were up to four times higher than in the other species.Under high irradiance, sulphite increased the thiol contents by an average of 40 % in L. valdiviana and Spirodela oligorhiza, but only by 20% in Lemna gibba. The greater light enhancement of thiol content exhibited by L. valdiviana and S. oligorhiza may be indicative of larger or more numerous sulphur sinks. The emission rates of H2S were also enhanced under high irradiance, and L. gibba exhibited a 17% increase relative to its rate in low irradiance. In comparison, L. valdiviana and S. oligorhiza exhibited 55 % and 60% increases, respectively.The ability to form elevated internal levels of thiols, and to emit H2S were found to be important in relation to sulphite tolerance in duckweeds. Enhancement of both processes under high irradiance may contribute to increased tolerance of sulphite in L. gibba and S. oligorhiza. It is hypothesized that thiol production and emission of H2S are important sulphite detoxification processes in duckweeds, and that enhancement of sulphite detoxification is fundamental to the modification by the photoenvironment of the sensitivity of duckweeds to sulphite.
DROUGHT RESISTANCE IN SESLERIA ALBICANS KIT. EX SCHULTES, COMPARED WITH AGROSTIS CAPILLARIS L. AND CYNOSURUS CRISTATUS L.
Authors: DIXON JEAN M. 
Published: May 2006

SummaryThe drought resistance of Sesleria albicans Kit. ex Schultes, a species of limestone cliffs, screes and dry grassland has been compared with that of Agrostis capillaris L., a species particularly prevalent on dry acid soils, and Cynosurus cristatus L., a species abundant in meadows and pastures on damp to dry soils. The response of the three species to different watering regimes, which produced fluctuating water stresses of graded severity, was examined. The total dry weight yield of S. albicans was the highest, and the quantity of shoot material which died was the lowest under all water stress regimes. The effects of a six‐week drought on the three species were monitored. Relative water content, drought damage and the capacity to recover were compared. S. albicans showed least damage and quickest recovery at all stages of the drought. The potential for drought avoidance was determined by examining the water status of excised leaves after desiccation, whilst potential for drought tolerance was estimated by monitoring their survival. The density of leaf epicuticular wax was determined for a comparative sample of the three species. S. albicans showed greater drought avoidance and tolerance, and had a greater density of leaf epicuticular wax, than the other two species. It was concluded that S. albicans is highly resistant to drought and as such is well adapted to survive as a ‘physical’ calcicole in dry limestone habitats.
COMPETITIVE INTERACTIONS AMONG FOREST TREE POPULATIONS IN NORFOLK, ENGLAND, DURING THE LAST 10000 YEARS
Authors: BENNETT K. D. 
Published: May 2006

SummaryThe post‐glacial pollen stratigraphies of two sequences of lake sediments (Hockham Mere and The Mere, Stow Bedon) are compared. Both suggest displacement of existing taxa when new taxa arrive from their cold‐stage refugia and expand their populations. Hockham Mere is within an area of sandy soils, while The Mere at Stow Bedon is within an area of calcareous till soils. There have been differences in the forest vegetation around the two sites for most of the last 10000 years, and the competitive interactions between the forest trees differ also.
UPTAKE OF AMINO ACIDS BY CULTURED AND FRESHLY ISOLATED SYMBIOTIC CHLORELLA
Authors: McAULEY P. J. 
Published: May 2006

SummaryAmino acid uptake was investigated in two cultured strains of symbiotic Chlorella sp., 3N813A and NC64A, and in Chlorella algae freshly isolated from symbiosis with the European strain of Hydra viridissima; E/E algae (the natural symbiont) and E/3N and E/NC algae (3N813A and NC64A in artificial symbiosis). Cultured 3N813A possessed at least two active uptake systems, a general system transporting proline, serine, alanine, glycine and glutamine, and one transporting arginine and lysine (although uptake of the latter was low). Unusually, arginine appeared to be transported in its neutral form, since low pH inhibited uptake. Cultured NC64A possessed only the arginine/lysine system, but in E/NC isolated from symbiosis the general system was also present. Algae freshly isolated from symbiosis showed a more active, rapidly saturated general transport system than cultured 3N813A, in which uptake was linear over a 2 h time course. Uptake of arginine was not affected by growth in symbiosis, but both E/3N and E/NC algae took up lysine at a faster rate than cultured 3N813A and NC64A. Attempts to induce higher activity of the two transport systems in cultured algae were mostly unsuccessful. Growth in nitrogen‐deficient medium reduced rather than increased uptake of proline and alanine by 3N813A, and it had no effect on lysine uptake; and although this treatment increased uptake of lysine by NC64A, neither nitrogen deficiency nor pretreatment with glucose induced the general transport system. The implications of the ability of algae symbiotic with hydra to take up amino acids are discussed with especial reference to host cell regulation of algal cell division.
GROWTH ANALYSIS AND SUCCESSIONAL STATUS OF COSTA RICAN RAIN FOREST TREES
Authors: OBERBAUER STEVEN F. , DONNELLY MAUREEN A. 
Published: May 2006

SummaryThe growth of seedlings of six species of tropical trees ranging from pioneer to shade‐tolerant canopy species was compared using sunflower (Helianthus animus L.) as a reference. Plants were grown in containers in a large clearing in the Atlantic lowlands of Costa Rica. Unit leaf rates of Ochroma lagopus Swartz, a pioneer species, were slightly lower but not significantly different from those of sunflower. With one exception, unit leaf rates increased from late‐ to early‐successional rank. Unit leaf rates of late‐successional species were 30 to 40% of that of sunflower. Relative growth rate, leaf area ratio, specific leaf weight, and root‐to‐shoot ratios also showed definite trends from early‐ to late‐successional rank. Multivariate analysis of these characteristics supported a priori rankings of these species.
Interactions between soil organic matter level and soil tillage in a growing crop: N mineralization and yield response
Authors: Thomsen I. K. , Sørensen P. 
Published: May 2006

AbstractFour levels of soil organic matter (SOM) had been established on a coarse sandy loam after application of four combinations of mineral fertilizer, animal manure, straw incorporation and catch crops for 12 years. Soil tillage was carried out in a growing spring barley crop (Hordeum vulgare) to examine the potential for improving the synchrony between soil N mineralization and crop N demand. Tillage raised soil nitrate concentrations temporarily but did not influence barley dry matter (DM) yield. At maturity, both grain DM yield and N uptake were largest on soil with the highest OM level. The previous OM applications had a pronounced influence on crop development and N availability, but soil tillage did not significantly improve the synchrony between soil N mineralization and crop N demand.
Methane and nitrous oxide fluxes, and carbon dioxide production in boreal forest soil fertilized with wood ash and nitrogen
Authors: Maljanen M. , Jokinen H. , Saari A. , Strömmer R. , Martikainen P. J. 
Published: May 2006

AbstractWood ash has been used to alleviate nutrient deficiencies and acidification in boreal forest soils. However, ash and nitrogen (N) fertilization may affect microbial processes producing or consuming greenhouse gases: methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2). Ash and N fertilization can stimulate nitrification and denitrification and, therefore, increase N2O emission and suppress CH4 uptake rate. Ash may also stimulate microbial respiration thereby enhancing CO2 emission. The fluxes of CH4, N2O and CO2 were measured in a boreal spruce forest soil treated with wood ash and/or N (ammonium nitrate) during three growing seasons. In addition to in situ measurements, CH4 oxidation potential, CO2 production, net nitrification and N2O production were studied in laboratory incubations. The mean in situ N2O emissions and in situ CO2 production from the untreated, N, ash and ash + N treatments were not significantly different, ranging from 11 to 17 μg N2O m−2 h−1 and from 533 to 611 mg CO2 m−2 h−1. However, ash increased the CH4 oxidation in a forest soil profile which could be seen both in the laboratory experiments and in the CH4 uptake rates in situ. The mean in situ CH4 uptake rate in the untreated, N, ash and ash + N plots were 153 ± 5, 123 ± 8, 188 ± 10 and 178 ± 18 μg m−2 h−1, respectively.
Twenty‐four weeks of interferon α‐2b in combination with ribavirin for Japanese hepatitis C patients: sufficient treatment period for patients with genotype 2 but not for patients with genotype 1
Authors: Fujiwara Keiichi , Yokosuka Osamu , Komine Fumihiko , Moriyama Mitsuhiko , Kato Naoya , Yoshida Haruhiko , Tanaka Naohide , Imazeki Fumio , Shiratori Yasushi , Arakawa Yasuyuki , Omata Masao ,   for Tokyo Hepatitis Network
Published: May 2006

Abstract: Background: Hepatitis C virus (HCV) RNA titer and HCV genotype are two major determinants of the outcome of interferon (IFN) monotherapy. To clarify the usefulness of combination therapy with IFN and ribavirin in Japanese hepatitis C patients, we treated patients with a relatively high dose of IFN in combination with ribavirin for 24 weeks and examined the effects in relation to the viral parameters.Methods: Two hundred and ninety‐five patients were enrolled in the study. The patients received either 6 or 10 million units (MU) of interferon α‐2b every day for 2 weeks and then three times a week for 22 weeks with a daily dose of either 600 or 800 mg of ribavirin. The treatment response and safety of this treatment were examined.Results: The sustained virologic response (SVR) rates were 26.8% in genotype 1 and 76.5% in genotype 2 (P<0.001), and 36.1% with the 6 MU group and 45.8% with the 10 MU group (P=0.09). Multivariate analysis indicated that SVR was associated with genotype 2, HCV RNA <500 kilointernational unit/ml (kIU/ml), and HCV RNA undetectability at week 8 of treatment.Conclusion: Our current study showed that a 24‐week course of IFN plus ribavirin combination therapy was effective with respect to virologic response in Japanese hepatitis C patients, particularly in patients with HCV genotype 2.
Sex preference of ankylosis in collagen‐induced arthritis in B10.RIII mice
Authors: ITO Jun , SAITO Tomoyuki 
Published: May 2006

AbstractAim:  The sex preference of ankylosis in collagen‐induced arthritis is evaluated.Method:  Mice were immunized with bovine type II collagen emulsified with complete Freund's adjuvant H37Ra. The incidence of arthritis, arthritic score, number of paws with whole rear‐paw swelling (WRPS), and number of paws with ankle ankylosis (Ankank) were monitored at various intervals after immunization.Results:  Arthritic score and number of paws with WRPS in each mouse were significantly higher in male than in female mice at 3, 5, and 8 weeks. On the other hand, there was no difference between male and female mice in arthritic score, number of paws with WRPS in each mouse, and number of paws with Ankank among ankles with WRPS at 10 and 15 weeks.Conclusion:  There was a suppressive effect on the development of arthritis in female mice. On the other hand, there was no sex difference in the incidence of ankylosis in arthritic ankles after arthritis was established.
DMARD combination therapy in rheumatoid arthritis: 5‐year follow‐up results in a daily practice setting
Authors: DAVATCHI Fereydoun , AKBARIAN Mahmood , SHAHRAM Farhad , NADJI Abdolhadi , GHARIBDOOST Farhad , JAMSHIDI Ahmad‐Reza 
Published: May 2006

AbstractAim:  To evaluate the overall effect of disease modifying anti‐rheumatic drug (DMARD) combination therapy in daily practice.Methods:  In a retrospective study, 161 consecutive files of patients who attended regular follow‐up sessions, seen from 1998, were analysed. Their data were extracted at baseline, 6 months, 1, 2, 3, 4 and 5 years. American College of Rheumatology ACR70 criteria was chosen for the evaluation of the global result. DMARD combination was methotrexate (7.5–15 mg weekly) and chloroquine (150 mg daily), with low‐dose prednisolone (less than 10 mg daily). In cases of remission, methotrexate was gradually tapered, then prednisolone. Chloroquine was discontinued after 1 year if no recurrence occurred at low‐dose (150 mg every other day). In cases of recurrence at any stage, the treatment scheme was stepped back.Results:  The data of 161 patients were analysed. One hundred and six were rheumatoid factor positive (RF+) (66%). ACR 70 for all patients at 6 months follow‐up was 72.5% (95% CI = 7.0); at 1 year, 75.8% (95% CI = 6.7); at 2 years, 72.2% (95% CI = 7.2); at 3 years, 78.9% (95% CI = 6.6); at 4 years, 78.4% (95% CI = 6.9); and at 5 years, 70.6% (95% CI = 8.5).Conclusion:  The classical DMARD combination therapy, when used with adequate low‐dose prednisolone, gave an ACR70 response from 71–79%. The efficacy of the treatment did not fade over time. RF– patients did better than RF+ patients, but the difference was not statistically significant.
Avascular necrosis of femoral head: a short review
Authors: TANG Wai Man , CHIU Kwong Yuen 
Published: May 2006

AbstractAvascular necrosis of femoral head (AVNFH) is the most common cause of hip joint destruction leading to hip replacement in Hong Kong. Steroids and alcohol are the two most common causes of AVNFH. Management of this painful and progressive situation in its early stages remains a controversial subject; but when the painful hip is affecting the patient's quality of life, a hip replacement is the treatment of choice for pain relief. However, there are concerns about the longevity of the hip replacement in this group of relatively young and active patients. Recent advances in the artificial hip joint such as the use of metal or ceramic may prolong the survival of the prosthesis even in very young and very active patients.
Genetic polymorphisms of chitotriosidase in Caucasian children with bronchial asthma
Authors: Bierbaum S. , Superti‐Furga A. , Heinzmann A. 
Published: May 2006

SummaryIn humans, two types of chitinases have been identified: chitotriosidase I (CHIT1) and acid mammalian chitinase (AMCase). They are enzymes that cleave chitin, a polysaccharide contained in many different human parasites. So far, only little is known about their function in human and especially in human diseases. Recently we have described association of polymorphisms of AMCase with bronchial asthma in a pediatric population. In this study we were interested in whether CHIT1 is also involved in the genetics of asthma.The amino acid variants Gly102Ser and Ala442Gly, as well as a 24 bp duplication within CHIT1, were typed by means of restriction fragment length polymorphisms on 322 children with asthma and 270 randomly chosen adult controls. Statistical analyses made use of the Armitage's trend test; haplotypes were calculated by famhap and fastehplus.The amino acid variants showed no association with bronchial asthma. The 24 bp duplication, previously shown to completely demolish CHIT1 activity, was also evenly distributed between asthmatics and controls. Finally, the haplotype showed no association with the disease.We conclude from our results that CHIT1 does not play a major role in the development of bronchial asthma in Caucasian children. The results might also imply that the two human chitinases that have been identified so far have quite distinct functions in human diseases even though they have the same substrate.
Abortion Legislation and the Future of the 'Counseling Model'
Authors: Gevers Sjef 
Published: May 2006

AbstractThis article aims at further reflection on the 'counseling model'. It is based on the recent evaluation of the Dutch abortion act. How has this model worked in the Netherlands? What can be learned from that experience about its weak and strong sides, as well as about its suitability for the future, taking into account relevant medical and societal developments? In doing so, the article first elaborates on three models relating them also to the present legal situation in a number of European countries. A description of the Dutch act and a report on the results of the evaluation study which was carried out in the years 2004–2005 is given. Finally, on the basis of these findings, the author discusses the merits of the 'counseling model', also with a view to the future.
Components of the antigen processing and presentation pathway revealed by gene expression microarray analysis following B cell antigen receptor (BCR) stimulation
Authors: Lee Jamie A , Sinkovits Robert S , Mock Dennis , Rab Eva L , Cai Jennifer , Yang Peng , Saunders Brian , Hsueh Robert C , Choi Sangdun , Subramaniam Shankar , Scheuermann Richard H ,   in collaboration with the Alliance for Cellular Signaling
Published: May 2006

AbstractBackgroundActivation of naïve B lymphocytes by extracellular ligands, e.g. antigen, lipopolysaccharide (LPS) and CD40 ligand, induces a combination of common and ligand-specific phenotypic changes through complex signal transduction pathways. For example, although all three of these ligands induce proliferation, only stimulation through the B cell antigen receptor (BCR) induces apoptosis in resting splenic B cells. In order to define the common and unique biological responses to ligand stimulation, we compared the gene expression changes induced in normal primary B cells by a panel of ligands using cDNA microarrays and a statistical approach, CLASSIFI (ClusterAssignmentfor BiologicalInference), which identifies significant co-clustering of genes with similar Gene Ontology™ annotation.ResultsCLASSIFI analysis revealed an overrepresentation of genes involved in ion and vesicle transport, including multiple components of the proton pump, in the BCR-specific gene cluster, suggesting that activation of antigen processing and presentation pathways is a major biological response to antigen receptor stimulation. Proton pump components that were not included in the initial microarray data set were also upregulated in response to BCR stimulation in follow up experiments. MHC Class II expression was found to be maintained specifically in response to BCR stimulation. Furthermore, ligand-specific internalization of the BCR, a first step in B cell antigen processing and presentation, was demonstrated.ConclusionThese observations provide experimental validation of the computational approach implemented in CLASSIFI, demonstrating that CLASSIFI-based gene expression cluster analysis is an effective data mining tool to identify biological processes that correlate with the experimental conditional variables. Furthermore, this analysis has identified at least thirty-eight candidate components of the B cell antigen processing and presentation pathway and sets the stage for future studies focused on a better understanding of the components involved in and unique to B cell antigen processing and presentation.