bluuebunny/crossref_metadata_2025_split huggingface dataset:
Beyond species: functional diversity and the maintenance of ecological processes and services
Authors: Cadotte Marc W. , Carscadden Kelly , Mirotchnick Nicholas 
Published: August 2011

Summary1. The goal of conservation and restoration activities is to maintain biological diversity and the ecosystem services that this diversity provides. These activities traditionally focus on the measures of species diversity that include only information on the presence and abundance of species. Yet how diversity influences ecosystem function depends on the traits and niches filled by species.2. Biological diversity can be quantified in ways that account for functional and phenotypic differences. A number of such measures of functional diversity (FD) have been created, quantifying the distribution of traits in a community or the relative magnitude of species similarities and differences. We review FD measures and why they are intuitively useful for understanding ecological patterns and are important for management.3. In order for FD to be meaningful and worth measuring, it must be correlated with ecosystem function, and it should provide information above and beyond what species richness or diversity can explain. We review these two propositions, examining whether the strength of the correlation between FD and species richness varies across differing environmental gradients and whether FD offers greater explanatory power of ecosystem function than species richness.4. Previous research shows that the relationship between FD and richness is complex and context dependent. Different functional traits can show individual responses to different gradients, meaning that important changes in diversity can occur with minimal change in richness. Further, FD can explain variation in ecosystem function even when richness does not.5. Synthesis and applications. FD measures those aspects of diversity that potentially affect community assembly and function. Given this explanatory power, FD should be incorporated into conservation and restoration decision‐making, especially for those efforts attempting to reconstruct or preserve healthy, functioning ecosystems.
Accounting for multi‐scale spatial autocorrelation improves performance of invasive species distribution modelling (iSDM)
Authors: Václavík Tomáš , Kupfer John A. , Meentemeyer Ross K. 
Published: August 2011

AbstractAim  Analyses of species distributions are complicated by various origins of spatial autocorrelation (SAC) in biogeographical data. SAC may be particularly important for invasive species distribution models (iSDMs) because biological invasions are strongly influenced by dispersal and colonization processes that typically create highly structured distribution patterns. We examined the efficacy of using a multi‐scale framework to account for different origins of SAC, and compared non‐spatial models with models that accounted for SAC at multiple levels.Location  We modelled the spatial distribution of an invasive forest pathogen, Phytophthora ramorum, in western USA.Methods  We applied one conventional statistical method (generalized linear model, GLM) and one nonparametric technique (maximum entropy, Maxent) to a large dataset on P. ramorum occurrence (n = 3787) to develop four types of model that included environmental variables and that either ignored spatial context or incorporated it at a broad scale using trend surface analysis, a local scale using autocovariates, or multiple scales using spatial eigenvector mapping. We evaluated model accuracies and amounts of explained spatial structure, and examined the changes in predictive power of the environmental and spatial variables.Results  Accounting for different scales of SAC significantly enhanced the predictive capability of iSDMs. Dramatic improvements were observed when fine‐scale SAC was included, suggesting that local range‐confining processes are important in P. ramorum spread. The importance of environmental variables was relatively consistent across all models, but the explanatory power decreased in spatial models for factors with strong spatial structure. While accounting for SAC reduced the amount of residual autocorrelation for GLM but not for Maxent, it still improved the performance of both approaches, supporting our hypothesis that dispersal and colonization processes are important factors to consider in distribution models of biological invasions.Main conclusions  Spatial autocorrelation has become a paradigm in biogeography and ecological modelling. In addition to avoiding the violation of statistical assumptions, accounting for spatial patterns at multiple scales can enhance our understanding of dynamic processes that explain ecological mechanisms of invasion and improve the predictive performance of static iSDMs.
The long and the short of it: SD1 polymorphism and the evolution of growth trait divergence in U.S. weedy rice
Authors: REAGON MICHAEL , THURBER CARRIE S. , OLSEN KENNETH M. , JIA YULIN , CAICEDO ANA L. 
Published: August 2011

AbstractGrowth‐related traits, such as greater height, greater biomass, faster growth rate and early flowering, are thought to enhance competitiveness of agricultural weeds. However, weedy rice, a conspecific weed of cultivated rice (Oryza sativa L.), displays variation for growth traits. In the United States, separately evolved weedy rice groups have been shown to share genomic identity with exotic domesticated cultivars. Through a common garden experiment, we investigated whether growth trait divergence has occurred among U.S. weeds and their putative cultivated progenitors. We also determined polymorphism patterns in the growth candidate gene, SD1, to assess its possible role in the evolution of divergent phenotypes. We found considerable growth trait variation among weed groups, suggesting that growth trait convergence is not evident among weedy populations. Phenotypic divergence of weedy rice from cultivated ancestors is most apparent for flowering time. Introgression of a chromosomal block containing the SD1 allele from tropical japonica, the predominant U.S. rice cultivar, was detected in one weedy rice population and is associated with a change in growth patterns in this group. This study demonstrates the role of introgressive hybridization in evolutionary divergence of an important weed.
Inactivation of a novel response regulator is necessary for biofilm formation and host colonization by Vibrio fischeri
Authors: Morris Andrew R. , Darnell Cynthia L. , Visick Karen L. 
Published: August 2011

SummaryThe marine bacterium Vibrio fischeri uses a biofilm to promote colonization of its eukaryotic host Euprymna scolopes. This biofilm depends on the symbiosis polysaccharide (syp) locus, which is transcriptionally regulated by the RscS–SypG two‐component regulatory system. An additional response regulator (RR), SypE, exerts both positive and negative control over biofilm formation. SypE is a novel RR protein, with its three putative domains arranged in a unique configuration: a central phosphorylation receiver (REC) domain flanked by two effector domains with putative enzymatic activities (serine kinase and serine phosphatase). To determine how SypE regulates biofilm formation and host colonization, we generated a library of SypE domain mutants. Our results indicate that the N‐terminus inhibits biofilm formation, while the C‐terminus plays a positive role. The phosphorylation state of SypE appears to regulate these opposing activities, as disruption of the putative site of phosphorylation results in a protein that constitutively inhibits biofilm formation. Furthermore, SypE restricts host colonization: (i) sypE mutants with constitutive inhibitory activity fail to efficiently initiate host colonization and (ii) loss of sypE partially alleviates the colonization defect of an rscS mutant. We conclude that SypE must be inactivated to promote symbiotic colonization by V. fischeri.
The superoxide dismutase SodA is targeted to the periplasm in a SecA‐dependent manner by a novel mechanism
Authors: Krehenbrink Martin , Edwards Anne , Downie J. Allan 
Published: August 2011

SummaryThe manganese/iron‐type superoxide dismutase (SodA) of Rhizobium leguminosarum bv. viciae 3841 is exported to the periplasm of R. l. bv. viciae and Escherichia coli. However, it does not possess a hydrophobic cleaved N‐terminal signal peptide typically present in soluble proteins exported by the Sec‐dependent (Sec) pathway or the twin‐arginine translocation (TAT) pathway. A tatC mutant of R. l. bv. viciae exported SodA to the periplasm, ruling out export of SodA as a complex with a TAT substrate as a chaperone. The export of SodA was unaffected in a secB mutant of E. coli, but its export from R. l. bv. viciae was inhibited by azide, an inhibitor of SecA ATPase activity. A temperature‐sensitive secA mutant of E. coli was strongly reduced for SodA export. The 10 N‐terminal amino acid residues of SodA were sufficient to target the reporter protein alkaline phosphatase to the periplasm. Our results demonstrate the export of a protein lacking a classical signal peptide to the periplasm by a SecA‐dependent, but SecB‐independent targeting mechanism. Export of the R. l. bv. viciae SodA to the periplasm was not limited to the genus Rhizobium, but was also observed in other proteobacteria.
The broadly conserved regulator PhoP links pathogen virulence and membrane potential in Escherichia coli
Authors: Alteri Christopher J. , Lindner Jonathon R. , Reiss Daniel J. , Smith Sara N. , Mobley Harry L. T. 
Published: August 2011

SummaryPhoP is considered a virulence regulator despite being conserved in both pathogenic and non‐pathogenic Enterobacteriaceae. While Escherichia coli strains represent non‐pathogenic commensal isolates and numerous virulent pathotypes, the PhoP virulence regulator has only been studied in commensal E. coli. To better understand how conserved transcription factors contribute to virulence, we characterized PhoP in pathogenic E. coli. Deletion of phoP significantly attenuated E. coli during extraintestinal infection. This was not surprising since we demonstrated that PhoP differentially regulated the transcription of > 600 genes. In addition to survival at acidic pH and resistance to polymyxin, PhoP was required for repression of motility and oxygen‐independent changes in the expression of primary dehydrogenase and terminal reductase respiratory chain components. All phenotypes have in common a reliance on an energized membrane. Thus, we hypothesized that PhoP mediates these effects by regulating genes encoding proteins that generate proton motive force. Indeed, bacteria lacking PhoP exhibited a hyperpolarized membrane and dissipation of the transmembrane electrochemical gradient increased susceptibility of the phoP mutant to acidic pH, while inhibiting respiratory generation of the proton gradient restored resistance to antimicrobial peptides independent of lipopolysaccharide modification. These findings demonstrate a connection between PhoP, virulence and the energized state of the membrane.
Age‐Dependent Alterations of HLA‐DR Expression and Effect of Lipopolysaccharide on Cytokine Secretion of Peripheral Blood Mononuclear Cells in the Elderly Population
Authors: Wu J. , Liu Z. , Zhang Y. , Wang L. , Feng D. , Liu L. , Peng Y. , Dai B. , Li W. 
Published: August 2011

AbstractHLA‐DR, a major histocompatibility complex, MHC class II, is involved in several autoimmune conditions, disease susceptibility and disease resistance. Here, we investigate the impact of different age individuals on HLA‐DR expression on peripheral blood mononuclear cells (PBMCs) induced by lipopolysaccharide (LPS). The results indicate that HLA‐DR expression on PBMCs in the population aged above 70 years significantly increased as compared with that in the lower‐age groups by flow cytometry analysis (B–D; r = 0.690, P = 0.000265). In addition, followed by LPS stimulation, the levels of cytokine TNF‐α, IL‐6 and IL‐10 secretion by allogeneic T lymphocytes from different age groups (A–D) were significantly increased (P < 0.05). Notably, levels of TNF‐α and IL‐6 were significantly reduced in groups B, C and D as compared with group A (P < 0.05), whereas levels of IL‐10 increased (P = 0.012). However, no significant difference in PBMC‐secreted TNF‐α, IL‐6 and IL‐10 levels was observed among groups A, B, C and D (P > 0.05) before LPS stimulation. We firstly present data showing an age‐dependent increase in HLA‐DR expression in the population aged above 70 years and the individual with aged above 70 years has reduced the secretion of inflammatory mediators (TNF‐α and IL‐6) by PBMCs and increased the secretion of anti‐inflammatory cytokine (IL‐10) after LPS stimulation in vitro. The better understanding of HLR–DR expression on human PBMCs in aged individuals and its relation to the host cellular immunity would provide important insights into the immunity of aged individuals and particularly, in elderly patients with sepsis.
Characterization of Monocyte‐Derived Dendritic Cells from Patients with Active and Treated Paracoccidioidomycosis
Authors: Sato P. K. , Oshiro T. M. , Diogo C. L. , Passos É. C. , Shikanai‐Yasuda M. A. 
Published: August 2011

AbstractCellular immune responses are a significant defence mechanism in human paracoccidioidomycosis (PCM), an endemic mycosis in Latin America; however, little is known about the role of dendritic cells (DCs) in human PCM. We investigated monocyte‐derived DCs from patients with treated (TP) and active PCM (AP) compared with healthy non‐PCM donors (CO). DCs from the TP group showed higher expression of HLA‐DR, CD86 and DC‐SIGN compared with CO, whereas AP showed similar expression to CO. Production of IL‐10 was downregulated by TNF‐α in all groups and lower levels were observed in untreated DCs from AP compared with CO. Conversely, IL‐12p40 was significantly upregulated in the DCs of the TP group. TNF‐α‐activated DCs from the CO group produced significantly lower levels of IL‐12p40 when differentiated from magnetic‐sorted monocytes (MACS) compared with adhered monocyte‐derived DCs. This comparison in the TP group revealed similar levels of IL‐12p40, suggesting a T cell–independent increase in the production of IL‐12p40. Higher expression of surface molecules with increased IL‐12p40 may indicate a better activation of DCs after the treatment of PCM. Our findings suggest that DCs may be crucial in the protective response to Paracoccidioides brasiliensis and that in vitro‐generated DCs might be useful in enhancing antifungal immunity, especially during active PCM.
Carbonate platform dominated by peloidal sands: Lower Ordovician La Silla Formation of the eastern Precordillera, San Juan, Argentina
Authors: PRATT BRIAN R. , RAVIOLO MARIANA M. , BORDONARO OSVALDO L. 
Published: August 2011

AbstractThe Lower Ordovician La Silla Formation of the Precordillera of west‐central Argentina is part of the west‐facing early Palaeozoic, tropical carbonate platform succession that comprises the core of the Cuyania terrane. Up to 360 m thick, it is exposed in several thrust sheets over a distance of some 250 km along and across depositional strike over a palinspastically unrestored distance of about 35 km. La Silla Formation is a strikingly pure limestone with subordinate finely crystalline dolomite and rare chert. It accumulated on a more or less uniformly subsiding passive margin. Copious precipitation of microcrystalline calcite, probably influenced by microbial activity to varying degrees, led to the generation of peloids, ooids and aggregates of these grains, as well as small amounts of lime mud, intraclasts, stromatolites and thrombolites. Rare bioclasts are limited mostly to scattered gastropods and trilobite sclerites; bioturbation is present locally. The array of carbonate rock types is grouped into eight recurring lithofacies, in order of decreasing abundance: (i) peloidal grainstone; (ii) laminated dolostone; (iii) intraclastic rudstone; (iv) microbial laminite; (v) peloidal packstone; (vi) ooidal grainstone; (vii) thrombolite boundstone; and (viii) mudstone. These facies represent sediments that formed solely in a shallow subtidal marine environment, with no evidence of restricted conditions, hypersalinity or subaerial exposure. No events of eustatic sea‐level change are recorded. By far the dominant facies is grainstone composed of well‐sorted, fine sand‐sized peloids and peloidal aggregates in homogeneous, tabular to gently undulating, medium to thick beds; cross‐lamination is scarce. Clusters of sub‐metre‐sized microbial patch reefs developed sporadically. The shallow platform is envisaged to have been covered by extensive peloidal sand flats and low‐relief banks, and little lime mud was generated. The setting was probably microtidal and may not have been affected by strong trade winds. It was washed by frequent, relatively gentle wave action but without experiencing powerful storms. In the middle member, anomalous lenses of intraclastic rudstone and laminated dolostone occur as graded beds overlying sharply downcut scoured surfaces up to 20 cm deep; these are interpreted to indicate a phase when accretion was punctuated occasionally by tsunamis generated from rift‐faulting seaward of the platform margin. The remarkably uniform peloidal grainstone composition over a broad area shows that, given the appropriate combination of climate, environmental and ecological factors, large portions of some early Palaeozoic platforms were dominated by grainy sediment and remained under well‐agitated conditions within fair‐weather wave‐base, without distinct lateral facies differentiation or tidal‐flat aggradation.
Dermatologists’ level of compliance with the prescription guidelines of isotretinoin for females of childbearing potential
Authors: AlGhamdi Khalid M. , Khurram Huma , Asiri Yousif A. , Mandil Ahmed 
Published: August 2011

AbstractBackground  Potent teratogenicity limits the use of isotretinoin among females of childbearing potential (FCBP).Objective  To explore the current practice of dermatologists for pregnancy prevention when prescribing isotretinoin for FCBP.Materials and methods  A self‐administered questionnaire was distributed to 160 dermatologists attending a national conference in Riyadh, Saudi Arabia, in 2008. The survey was designed to capture the details of precautions taken by dermatologists to prevent pregnancy among isotretinoin users.Results  Ultimately, 134 dermatologists completed the questionnaire (84% response rate). Their mean age was 39 ± 9.5 years. A total of 82 were female (65%). The median number of FCBP for whom isotretinoin was prescribed by each dermatologist during the previous 12 months was two (range from 0 to 30). Of the 792 total FCBP, seven were reported to have become pregnant (incidence rate of 8.8/1000) while on isotretinoin. Out of those seven, three women terminated the pregnancy (elective abortions: 42.7%). The majority of the dermatologists (79%) always obtained written consent and discussed teratogenic risks (98%); 44% provided written information about potential isotretinoin teratogenicity, and 30% offered printed information on contraception. Survey results also revealed that 62% recommended double contraception for FCBP, 60% always recommended pregnancy testing prior to therapy, but only 16% requested monthly pregnancy tests. In general, 62.4% avoided isotretinoin prescription to FCBP, which was independent of dermatologists’ gender, years of experience, or having a previous incident of isotretinoin‐exposed pregnancy.Conclusion  Some dermatologists still do not follow the recommendations for isotretinoin prescription to FCBP. This needs to be corrected, especially in countries with restrictions on abortion.
Overview of efficacy and safety of tacrolimus ointment in patients with atopic dermatitis in Asia and other areas
Authors: Kim Kyu‐Han , Kono Takeshi 
Published: August 2011

AbstractObjective  To assess the efficacy and safety of tacrolimus ointment in a large population of patients with atopic dermatitis (AD) by pooling data from individual Asian studies, and to compare the results of this study with those in the United States, Europe, and Japan.Materials and methods  We analyzed the pooled data from individual studies conducted in the eight Asian areas. The efficacy assessments included success rate based on Physician’s Global Evaluation of Clinical Response, Eczema Area Severity Index (EASI), Percent Body Surface Area (%BSA) affected, Patient’s Assessment of Itch (Itch), Dermatology Life Quality Index (DLQI) and children’s DLQI (CDLQI). The results that were published in the United States, Europe, and Japan were cited.Results  A total of 860 patients were included in this study. The success rates were more than 80% in both adult and pediatric patients. Similar success rates were shown in the United States, European, and Japanese studies. There were no differences in the improvements in %BSA affected, EASI, and Itch between this study and the United States study. In both Asia and the United States, tacrolimus therapy improved total quality of life and all subscales in DLQI and CDLQI. Skin burning and pruritus were common adverse events among the Asian, United States and European studies.Conclusions  Tacrolimus ointment is an effective and well‐tolerated treatment option in patients with AD in Asia. In this study, the efficacy and safety of tacrolimus are similar to those in the United States, European, and Japan studies.
Wound healing in adult skin: aiming for perfect regeneration
Authors: Heng Madalene C. Y. 
Published: August 2011

AbstractWound healing in adult skin, a complex process involving many cell types and processes such as epidermal, fibroblastic, and endothelial cell proliferation, cell migration, matrix synthesis, and wound contraction, almost invariably results in scar tissue formation and wound induration. Unlike in adult skin, wound healing in embryos involves repair processes that result in the essentially perfect regeneration of damaged tissue. This paper discusses key mechanisms that lead to scar tissue formation in adult human skin and treatment modalities, including curcumin gel, that may result in essentially perfect skin regeneration following surgical procedures.
Prospective trial of curettage and cryosurgery in the management of non‐facial, superficial, and minimally invasive basal and squamous cell carcinoma
Authors: Peikert Johann M. 
Published: August 2011

AbstractBackground  As a variation of the curettage and destruction technique, cryosurgery can be used in place of electrodesiccation for the destructive component when managing superficial basal and squamous cell carcinomas. There are few studies, though, demonstrating the long‐term cure rate associated with similar methods. This study seeks to determine the long‐term cure rate associated with curettage and cryosurgery in the treatment of small, non‐facial, superficial basal and squamous cell carcinomas.Materials and methods  Sixty‐nine patients with 100 non‐facial tumors, ≤2 cm in diameter, consisting of superficial basal cell carcinoma, superficial nodular basal cell carcinoma with papillary dermal invasion, squamous cell carcinoma in situ, and squamous cell carcinoma with papillary dermal invasion were prospectively treated with curettage and cryotherapy, and subsequently evaluated at 1‐ and 5‐year intervals.Results  No tumor recurred after one year of follow‐up, and one recurrence occurred within the 5‐year interval, for a 99% recurrence‐free endpoint. Six patients died of unrelated causes after one year, and before five years, and were thus lost to follow‐up.Conclusions  Curettage and cryosurgery is a simple, highly effective, and reliable treatment method for select, low‐risk non‐melanoma skin cancers.