bluuebunny/crossref_metadata_2025_split huggingface dataset:
A call for a new paradigm of island biogeography
Authors: Lomolino MarK. V. 
Published: March 2003

AbstractMacArthur and Wilson’s equilibrium theory of island biogeography quickly became the paradigm of the field in the 1960s and has strongly influenced this and other disciplines of ecology and conservation biology for the past three decades. Recently, however, a growing number of ecologists have begun to question whether the theory remains a useful paradigm for modern ecology. We now have a much better appreciation for the complexity of nature and we study patterns that span a very broad range in spatial, temporal and ecological scales. At such scales, assumptions that communities are in equilibrium, that species, islands and intervening landscapes or seascapes are equivalent or homogeneous with respect to factors influencing immigration and extinction, and that in situ speciation can be overlooked become very tenuous. With this in mind, this and other papers of this special feature discuss the principal, conceptual shortcomings of the equilibrium theory and offer some modifications or alternatives to the theory that we hope will eventually lead to a more comprehensive understanding of the forces structuring insular communities.
A species‐based theory of insular zoogeography
Authors: Lomolino Mark V. 
Published: March 2003

Abstract

I present an alternative to the equilibrium theory of island biogeography, one which is based on the premise that many of the more general patterns in insular community structure result from, not despite, nonrandom variation among species.
For the sake of simplicity, the model is limited to patterns and processes operating over scales of ecological space and time: evolution is not included in the current version of the model.
The model assumes, as did MacArthur and Wilson’s model, that insular community structure is dynamic in ecological time, but the model does not assume a balance, or equilibrium, of immigration and extinction.
The model presented here is hierarchical, phenomenological (it requires little parameterization beyond that which is directly derived from distributional data), graphical, and it includes potential feedback processes (including interspecific interactions).
The model offers an alternative explanation for a variety of patterns ranging from distributions of individual species, species–area and species–isolation relationships, to patterns of assembly of insular communities. The model also generates some new predictions and identifies some potentially important areas for future studies.
The role of local and regional processes in shaping dung beetle communities in tropical forest plantations in Borneo
Authors: Davis Andrew J. , Huijbregts Hans , Krikken Jan 
Published: March 2003

AbstractWe examine whether rain forest dung beetle species found in plantations in Sabah, northern Borneo, tend to be endemic or geographically widespread. In addition, linear regressions of abundance vs. distance from a major river in primary rain forest are calculated to see if species found in plantation forest show affinity to one specific biotope (riverine vs. interior forest) in their natural habitat. Results show that 14 of the 40 species recorded from plantations are endemic to Borneo. Only edge‐specialist endemic species are found in plantation forest, with no interior‐forest specialists recorded. Data suggest that endemic species that are adapted to more exposed conditions in primary rain forest, such as riverine species, can in some instances tolerate man‐made habitats. Twenty‐nine species (±SE 4.0) per transect are recorded from plantation transects, whereas 44.2 (±1.7 SE) are recorded in primary rain forest. As species richness is much lower in plantations than natural forest, implying loss of biodiversity, we conclude that measures of biogeographic distinctiveness, whereby endemic species confer higher values, may be misleading unless they take into account edge‐affinity. Local‐ as well as regional‐distributional data may therefore be needed to interpret correctly patterns of species assemblages in derived forest ecosystems.
Biogeographic history of geminate cirrhitoids (Perciformes: Cirrhitoidea) with east–west allopatric distributions across southern Australia, based on molecular data
Authors: Burridge Christopher P. 
Published: March 2003

AbstractThe biogeographic history of three cirrhitoid species pairs with east–west allopatric distributions across southern Australia was examined by determining levels of mitochondrial DNA sequence divergence and applying molecular clock calibrations. Similar levels of genetic divergence were observed for Aplodactylus Valenciennes and Goniistius Gill species pairs, but these were more than twice that observed for a Nemadactylus Richardson pair. Molecular clock calibrations suggested divergences occurred during the late Miocene and mid Pliocene, respectively. Given evidence of high dispersal capabilities, the habitat and climatic barriers of the Australian south coast appear too small to have facilitated speciation of the cirrhitoids examined. A mechanism is proposed by which ancestral cirrhitoids were vicariantly isolated into east and west coast populations during periods of climate change. Although Aplodactylus and Goniistius divergences occurred during the same period, separate vicariant events across the Australian north and south coasts are invoked.
Increases in collagen type I synthesis in asthma: the role of eosinophils and transforming growth factor‐bβ
Authors: Nomura A. , Uchida Y. , Sakamoto T. , Ishii Y. , Masuyama K. , Morishima Y. , Hirano K. , Sekizawa K. 
Published: March 2003

SummaryBackground Collagen type I is one of the major deposits in thickening of the reticular basement membrane of asthma.Objective and Methods In this study, we assessed turnover of collagen type I in asthma by measuring procollagen type I C‐terminal peptide (PICP) and collagen type I C‐terminal telopeptide (ICTP) in induced sputum.Results PICP but not ICTP was found to be significantly higher in asthma subjects than in normal volunteers (P < 0.05). In asthma, PICP was inversely correlated with %FEV1.0 (r = −0.539), and its levels significantly increased upon exacerbation (P < 0.05), indicating that collagen synthesis increases during asthma exacerbation. Additionally, PICP was found to significantly correlate with eosinophil counts in sputum (r = 0.539), indicating that eosinophils stimulate collagen turnover. Because eosinophils can produce TGF‐β, a potent stimulator of collagen synthesis, we immunocytochemically examined TGF‐β‐positive cells in sputum. TGF‐β‐positive cells significantly correlated with eosinophil counts (r = 0.811) and PICP (r = 0.569), suggesting that TGF‐β released from eosinophils is involved in collagen synthesis.Conclusions The results of the present study suggest that collagen synthesis is stimulated in asthmatic airways by eosinophils through TGF‐β, while collagen degradation is not, and that PICP in sputum can act as a new marker for airway inflammation in asthma.
Particulate masks and non‐powdered gloves reduce latex allergen inhaled by healthcare workers
Authors: Mitakakis T. Z. , Tovey E. R. , Yates D. H. , Toelle B. G. , Johnson A. , Sutherland M. F. , O'Hehir R. E. , Marks G. B. 
Published: March 2003

SummaryBackground Although allergy to latex is a well‐characterized phenomenon, some hospitals continue to provide staff with powdered latex gloves as an option to low‐ or non‐powdered gloves.Objective We aimed to measure the extent to which inhalation of latex particles could be reduced by the use of protective masks or by replacing powdered latex gloves with non‐powdered latex gloves.Methods Twenty healthcare workers in a hospital setting wore nasal air samplers (NAS) and Institute of Occupational Medicine (IOM) samplers for four 20‐min periods. Subjects wore powdered gloves, non‐powdered gloves and no gloves during three sampling periods, and in the fourth, subjects applied an aerosol barrier face‐mask or a particulate face‐mask (N95) while wearing powdered gloves. All samples were stained for particles bearing Hev b 5 allergen by the Halogen assay.Results All subjects inhaled Hev b 5 bearing particles in all sampling periods. IOM samplers collected particles at 70% of the rate of NAS. The number of particles inhaled while wearing powdered gloves was 23.8‐fold higher than when not wearing gloves and 9.7‐fold higher than when wearing non‐powdered latex gloves (P < 0.0001). Wearing an aerosol barrier mask did not significantly reduce the number of particles inhaled (P = 0.108), while use of particulate masks significantly reduced the number of particles inhaled by 17.4‐fold (P = 0.003).Conclusions Use of non‐powdered gloves is the most effective method of reducing occupational aeroallergen exposure to latex arising from gloves. However, secondary protection using particulate masks is a valid alternative, and may be helpful for preventing respiratory sensitization.
Allergenicity of some isoforms of white sesame proteins
Authors: Fremont S. , Zitouni N. , Kanny G. , Veneri V. , Metche M. , Moneret‐Vautrin D. A. , Nicolas J. P. 
Published: March 2003

SummaryBackground Allergy to sesame seeds is often associated with particularly severe reactions, with a high risk of anaphylaxis. The increase in reports of allergic reactions to sesame is probably due to the growing use of sesame seeds or sesame oil in food.Objective To determine the molecular weights of the proteins in three variety of sesame seeds and to study the isoelectric points and the allergenicity of white sesame proteins.Methods Extracts of white, brown and black sesame seeds were prepared. The white sesame extract, mostly used in bakery, was run on SDS‐PAGE and two dimensional electrophoresis. Six sera from patients sensitized or symptomatic to sesame seed were used for Western blotting.Results The protein patterns of the white, brown and black sesame extracts showed major quantitative differences. The white extract had the higher protein concentration and contained 15 proteins of 12–79 kDa, some of them having several acidic isoelectric points. The lowest isoelectric point was 4.9 and the highest was 6.4, giving 35 isoforms. Ten of the 15 proteins (12–57.5 kDa) were recognized by specific IgE. The 12–13 kDa and 22–33 kDa proteins could correspond to the main allergens.Conclusion White sesame seeds contain at least 10 allergenic proteins with acidic isoelectric points. In accordance with previous results, two of them seem to contain the major allergens.
Consumer collaboration, patient‐defined outcomes and the preparation of Cochrane Reviews
Authors: Kelson Marcia C. 
Published: March 2003

ObjectivesTo identify the extent to which the Cochrane Collaboration involves consumers (patients, carers, patient and non‐patient members of patient/consumer organizations) as members of Cochrane Review Groups (CRGs); to explore the emphasis CRGs place on identifying and collecting information on outcomes identified by patients as being important indicators of quality and effectiveness of treatment and care (‘patient‐defined outcomes’).MethodA postal questionnaire designed by The College of Health, a UK patient organization, was sent in January 1998 to all CRGs registered with the Cochrane Collaboration on 1 January 1998 (n = 42).Results and conclusionsReplies were received from 35 CRGs, a response rate of 83% and 33 questionnaires (79%) were completed. The survey revealed that CRGs varied in the extent to which they had recruited consumer members: almost one third of respondents said their CRG did not have any consumer members. There was also no apparent consensus across CRGs on the importance attached to identifying and collecting information on patient‐defined outcomes or on integrating such information into their activities. It is hoped that differences between CRGs may inform discussions as to whether and how the Cochrane Collaboration might address the issue of patient‐defined outcomes in the future.
‘People sometimes react funny if they're not told enough’: women's views about the risks of diagnostic laparoscopy
Authors: Moore Jane , Ziebland Sue , Kennedy Stephen 
Published: March 2003

AbstractObjectives To explore women's views about the risks and benefits of diagnostic laparoscopy in the investigation of chronic pelvic pain, including how much information it is thought appropriate to give about three specific risks: death, major complications and the chance that the procedure would have an inconclusive result.Design A qualitative analysis of semi‐structured, audio‐taped interviews with 20 women about their experiences of undergoing a diagnostic laparoscopy in a day surgery unit. Interviews were conducted 3–6 months after the procedure.Results All the women who were interviewed were aware that diagnostic laparoscopy carried risks, including the small risk of death associated with general anaesthesia. One‐third of respondents said that they had initially been reluctant to discuss the risks of the procedure in general terms. However, when specific examples of complications and risks were introduced all but one of the respondents reported that theywouldhave liked to discuss these at the time that the decision to have the operation was made. Women maintained that the information was needed to make an informed decision about whether to have the operation, to help them understand and cope should things go wrong and in order to make appropriate plans to cover contingencies. Most were surprised to hear that the procedure is frequently inconclusive and thought that this information should be made clear to women contemplating a laparoscopy.Conclusions Women undergoing diagnostic laparoscopy for the investigation of chronic pelvic pain wish to be given full and accurate information about complication rates such as bowel perforation, what to expect during their recovery, and the chances of finding a cause for their pain. Although they may not want to dwell on the risk of death, they do need to be informed about the specific risks associated with the procedure in order to make a balanced decision.
Developing patient‐centred information for back pain sufferers
Authors: Glenton Claire , Polit. Cand. 
Published: March 2003

AbstractObjective To identify information needs among a group of back pain sufferers as well as the barriers that may prevent them from accessing this information.Design Data were collected through the use of open, in‐depth interviews, through contributions to the Norwegian Back Pain Association's online discussion list, and through a search of the literature.Participants Norwegian back pain sufferers and their carers.Main variables studied Information needs and barriers.Results The informants described information needs that covered a wide range of topics, clinical, financial, emotional and social. Informants wanted to understand the cause of their pain and wanted information about existing diagnoses and diagnostic procedures. Informants asked for information about treatment alternatives, both within and outside the established health‐care system, the effects of these treatment alternatives, their procedures, side‐effects and costs. In addition, informants wanted information about the social and emotional effects of long‐term pain; coping with everyday life; other people's experiences; and about welfare benefits and patient rights. Barriers to this information included the use of medical, legal and other jargon, doctors’ lack of time, lack of communication skills, lack of knowledge about back pain and attitudes to back pain patients.Conclusions To successfully address the questions and concerns of users, there should be an attempt to present information on as many of these topics as possible. Information should be presented in the user's own language, at several levels of understanding, and should include both evidence‐ and experienced‐based knowledge.
RNase L inhibitor (RLI) antisense constructions block partially the down regulation of the 2‐5A/RNase L pathway in encephalomyocarditis‐virus‐(EMCV)‐infected cells
Authors: Martinand Camille , Salehzada Tamim , Silhol Michelle , Lebleu Bernard , Bisbal Catherine 
Published: March 2003

The interferon‐(IFN)‐inducible 2′,5′‐oligoadenylate (2‐5A)/endoribonuclease L (RNase L) pathway plays a major role in the antiviral and antiproliferative effects of IFN. The 2‐5A/RNase L pathway appears to be regulated by the cell‐growth status or viral infection. Viruses, and picornaviruses in particular, have evolved strategies to escape the 2‐5A/RNase L‐pathway‐associated antiviral activity.We have recently cloned a cDNA coding for RLI, a RNase‐L‐specific protein inhibitor. Its regulated expression by viral infection could provide a new strategy to modulate the 2‐5A/RNase L pathway. Since RNase L had been shown to be down regulated upon encephalomyocarditis (EMCV) infection, we stably transfected HeLa cells with a RLI antisense cDNA expressing vector. Four independant clones named VAS1, VAS2, VAS3 and VAS4 and one clone transfected with the empty vector (VV) as control, were analyzed. The level of RLI was decreased by 20  % for VAS1, 25  % for VAS2, 75  % for VAS3 and 50  % for VAS4. The inactivation of RNase L observed during EMCV infection was decreased in these clones as compared to control HeLa cells. Here again the results vary between the four clones. The maximum inhibition of RNase L (90  %) was observed in control cells and in VAS1 while 48  % inhibition was observed in VAS4 and 25  % in VAS3. The reversal in RNase L inhibition thus reflects closely the resulting RLI level, in keeping with a major role of RLI in EMCV‐induced down regulation of 2‐5A‐binding activity of RNase L. Moreover, cells expressing a low level of RLI (VAS3 and VAS 4) are partially resistant to EMCV infection.
Purification and characterization of two enone reductases from Saccharomyces cerevisiae
Authors: Wanner Peter , Tressl Roland 
Published: March 2003

Two enone reductases catalyzing irreversibly the enantioselective reduction of α,β‐unsaturated carbonyls have been purified 165‐fold and 257‐fold, respectively, from the cytosolic fraction of Saccharomyces cerevisiae by means of streptomycin sulfate treatment, Sephadex G‐25 filtration, DEAE‐Sepharose CL‐6B chromatography, blue Sepharose CL‐6B chromatography and Superdex 200 preparation‐grade filtration.One enzyme (E I) was NADPH‐dependent, showed a molecular mass of 75 kDa and decomposed under denaturing electrophoretic conditions into two subunits of 34 kDa and 37 kDa. The other enzyme (E II) was NADH linked and the molecular mass estimated by means of Superdex 200 preparation‐grade filtration, was 130 kDa. The enzyme decomposed into subunits of 56 kDa and 64 kDa on SDS/PAGE.Both enzymes were most active at pH 4.8 and accepted 1‐octen‐3‐one, 1‐hexen‐3‐one, 3‐alken‐2‐ones, 4‐alken‐3‐ones, 2‐cyclohexen‐1‐ones, 2‐alkenals, 2,4‐alkadienals, 2‐phenyl‐2‐alkenals, and 2‐alkyl‐2‐alkenals as substrates. Both enzymes showed their highest activities with 1‐hexen‐3‐one and 1‐octen‐3‐one, respectively. The Km values for 1‐octen‐3‐one were estimated as 0.54 mM (E I) and 0.20 mM (E II), respectively. Both enzymes catalyzed the enantioselective reduction of cis‐ and trans‐2‐phenyl‐2‐butenal into (R)‐2‐phenylbutanal.
Domain structure, GTP‐hydrolyzing activity and 7S RNA binding of Acidianus ambivalens Ffh‐homologous protein suggest an SRP‐like complex in archaea
Authors: Moll Ralf , Schmidtke Silke , Schäfer Günter 
Published: March 2003

In this study we provide, for the first time, experimental evidence that a protein homologous to bacterial Ffh is part of an SRP‐like ribonucleoprotein complex in hyperthermophilic archaea. The gene encoding the Ffh homologue in the hyperthermophilic archaeote Acidianus ambivalens has been cloned and sequenced. Recombinant Ffh protein was expressed in E. coli and subjected to biochemical and functional studies.  A. ambivalens Ffh encodes a 50.4‐kDa protein that is structured by three distinct regions: the N‐terminal hydrophilic N‐region (N), the GTP/GDP‐binding domain (G) and a C‐terminal located C‐domain (C). The A. ambivalens Ffh sequence shares 44–46% sequence similarity with Ffh of methanogenic archaea, 34–36% similarity with eukaryal SRP54 and 30–34% similarity with bacterial Ffh. A polyclonal antiserum raised against the first two domains of A. ambivalens Ffh reacts specifically with a single protein (apparent molecular mass: 46 kDa, termed p46) present in cytosolic and in plasmamembrane cell fractions of A. ambivalens. Recombinant Ffh has a melting point of tm = 89 °C. Its intrinsic GTPase activity obviously depends on neutral pH and low ionic strength with a preference for chloride and acetate salts. Highest rates of GTP hydrolysis have been achieved at 81 °C in presence of 0.1–1 mm Mg2+. GTP hydrolysis is significantly inhibited by high glycerol concentrations, and the GTP hydrolysis rate also markedly decreases by addition of detergents. The Km for GTP is 13.7 µm at 70 °C and GTP hydrolysis is strongly inhibited by GDP (Ki = 8 µm). A. ambivalens Ffh, which includes an RNA‐binding motif in the C‐terminal domain, is shown to bind specifically to 7S RNA of the related crenarchaeote Sulfolobus solfataricus. Comparative sequence analysis reveals the presence of typical signal sequences in plasma membrane as well as extracellular proteins of hyperthermophilic crenarchaea which strongly supposes recognition events by an Ffh containing SRP‐like particle in these organisms.
Structural analysis of the lipopolysaccharide oligosaccharide epitopes expressed by a capsule‐deficient strain of Haemophilus influenzae Rd
Authors: Risberg Anna , Masoud Hussein , Martin Adèle , Richards James C. , Moxon E. Richard , Schweda Elke K. H. 
Published: March 2003

Structural elucidation of the lipopolysaccharide (LPS) of Haemophilus influenzae, strain Rd, a capsule‐deficient type d strain, has been achieved by using high‐field NMR techniques and electrospray ionization‐mass spectrometry (ESI‐MS) on delipidated LPS and core oligosaccharide samples. It was found that this organism expresses heterogeneous populations of LPS of which the oligosaccharide (OS) epitopes are subject to phase variation. ESI‐MS of O‐deacylated LPS revealed a series of related structures differing in the number of hexose residues linked to a conserved inner‐core element, l‐α‐d‐Hepp‐(1→2)‐l‐α‐d‐Hepp‐(1→3)‐[β‐d‐Glcp‐(1→4)‐]‐l‐α‐d‐Hepp‐(1→5)‐α‐Kdo, and the degree of phosphorylation. The structures of the major LPS glycoforms containing three (two Glc and one Gal), four (two Glc and two Gal) and five (two Glc, two Gal and one GalNAc) hexoses were substituted by both phosphocholine (PCho) and phosphoethanolamine (PEtn) and were determined in detail. In the major glycoform, Hex3, a lactose unit, β‐d‐Galp‐(1→4)‐β‐d‐Glcp, is attached at the O‐2 position of the terminal heptose of the inner‐core element. The Hex4 glycoform contains the PK epitope, α‐d‐Galp‐(1→4)‐β‐d‐Galp‐(1→4)‐β‐d‐Glcp while in the Hex5 glycoform, this OS is elongated by the addition of a terminal β‐d‐GalpNAc residue, giving the P antigen, β‐d‐GalpNAc‐(1→3)‐α‐d‐Galp‐(1→4)‐β‐d‐Galp‐(1→4)‐d‐Glcp. The fully extended LPS glycoform (Hex5) has the following structure.The structural data provide the first definitive evidence demonstrating the expression of a globotetraose OS epitope, the P antigen, in LPS of H. influenzae. It is noteworthy that the molecular environment in which PCho units are found differs from that observed in an Rd− derived mutant strain (RM.118–28) [Risberg, A., Schweda, E. K. H. & Jansson, P‐E. (1997) Eur. J. Biochem.243, 701–707].