bluuebunny/crossref_metadata_2025_split huggingface dataset:
The influence of sea currents, past disruption of gene flow and species biology on the phylogeographical structure of coastal flowering plants
Authors: Westberg Erik , Kadereit Joachim W. 
Published: August 2008

AbstractAim  We investigate the geographical genetic structure of two coastal plant species, Cakile maritima Scop. (Brassicaceae) and Eryngium maritimum L. (Apiaceae), through three sea straits and along one continuous stretch of coast using amplified fragment length polymorphisms (AFLPs). The two species have a similar ecology in that they grow in sandy habitats, but differ in life‐form (annual vs. perennial) and dispersability of seeds by sea water as inferred from floating experiments. The sea straits differ in their geological history and their modern current systems. The primary goal of our study was to test the hypothesis that sea straits have an influence on the geographical patterns of genetic variation at the population level.Location  The areas around the Strait of Gibraltar, the Dardanelles, the Bosporus and the Atlantic coast of western France.Methods  For both species we investigated AFLP variation in several populations from each area. Bayesian clustering and diversity and differentiation measures were used to analyse the genetic data.Results  In most areas the spatial genetic structure was similar between the two species. They share the presence of distinct genetic gaps along the coast through the Strait of Gibraltar and the Bosporus, and these genetic gaps coincide with the straits. Both species show genetic continuity along the coast of western France. A distinct genetic gap was found through the Dardanelles for C. maritima but not for E. maritimum.Main conclusions  The study shows that sea straits have an influence on the geographical patterns of genetic variation. Sea currents are inferred to cause the genetic gap through the Strait of Gibraltar. In the Bosporus and, for C. maritima, through the Dardanelles, the genetic gaps found are explained by the past closure of these two straits as well as by present‐day factors. Simulations indicate that the lower differentiation of C. maritima through the Dardanelles than through the Bosporus cannot be explained by the difference in geological history of these two straits. The difference in seed dispersability between the two species is argued to be responsible for the observation that differentiation among genetic clusters is higher in E. maritimum than in C. maritima where a direct comparison is possible.
Interpretation of the last‐glacial vegetation of eastern‐central Europe using modern analogues from southern Siberia
Authors: Kuneš Petr , Pelánková Barbora , Chytrý Milan , Jankovská Vlasta , Pokorný Petr , Petr Libor 
Published: August 2008

AbstractAim  Interpretation of fossil pollen assemblages may benefit greatly from comparisons with modern palynological and vegetation analogues. To interpret the full‐ and late‐glacial vegetation in eastern‐central Europe we compared fossil pollen assemblages from this region with modern pollen assemblages from various vegetation types in southern Siberia, which presumably include the closest modern analogues of the last‐glacial vegetation of central Europe.Location  Czech and Slovak Republics (fossil pollen assemblages); Western Sayan Mountains, southern Siberia (modern pollen assemblages).Methods  Eighty‐eight modern pollen spectra were sampled in 14 vegetation types of Siberian forest, tundra and steppe, and compared with the last‐glacial pollen spectra from seven central European localities using principal components analysis.Results  Both full‐ and late‐glacial pollen spectra from the valleys of the Western Carpathians (altitudes 350–610 m) are similar to modern pollen spectra from southern Siberian taiga, hemiboreal forest and dwarf‐birch tundra. The full‐glacial and early late‐glacial pollen spectra from lowland river valleys in the Bohemian Massif (altitudes 185–190 m) also indicate the presence of patches of hemiboreal forest or taiga. Other late‐glacial pollen spectra from the Bohemian Massif suggest an open landscape with steppe or tundra or a mosaic of both, possibly with small patches of hemiboreal forest.Main conclusions  Our results are consistent with the hypothesis that during the full glacial and late glacial, the mountain valleys of the north‐western Carpathians supported taiga or hemiboreal forest dominated by Larix, Pinus cembra, Pinus sylvestris and Picea, along with some steppic or tundra formations. Forests tended to be increasingly open or patchy towards the west (Moravian lowlands), gradually passing into the generally treeless landscape of Bohemia, with possible woodland patches in locally favourable sites.
Historical divergence vs. contemporary gene flow: evolutionary history of the calcicole Ranunculus alpestris group (Ranunculaceae) in the European Alps and the Carpathians
Authors: PAUN O. , SCHÖNSWETTER P. , WINKLER M. , CONSORTIUM INTRABIODIV , TRIBSCH A. 
Published: August 2008

AbstractAlthough many species have similar total distributional ranges, they might be restricted to very different habitats and might have different phylogeographical histories. In the European Alps, our excellent knowledge of the evolutionary history of silicate‐dwelling (silicicole) plants is contrasted by a virtual lack of data from limestone‐dwelling (calcicole) plants. These two categories exhibit fundamentally different distribution patterns within the Alps and are expected to differ strongly with respect to their glacial history. The calcicole Ranunculus alpestris group comprises three diploid species of alpine habitats. Ranunculus alpestris s. str. is distributed over the southern European mountain system, while R. bilobus and R. traunfellneri are southern Alpine narrow endemics. To explore their phylogenetic relationships and phylogeographical history, we investigated the correlation between information given by nuclear and chloroplast DNA data. Analyses of amplified fragment length polymorphism fingerprints and matK sequences gave incongruent results, indicative for reticulate evolution. Our data highlight historical episodes of range fragmentation and expansion, occasional long‐distance dispersal and on‐going gene flow as important processes shaping the genetic structure of the group. Genetic divergence, expressed as a rarity index (‘frequency‐down‐weighted marker values’) seems a better indicator of historical processes than patterns of genetic diversity, which rather mirror contemporary processes as connectivity of populations and population sizes. Three phylogeographical subgroups have been found within the R. alpestris group, neither following taxonomy nor geography. Genetic heterogeneity in the Southern Alps contrasts with Northern Alpine uniformity. The Carpathians have been stepwise‐colonised from the Eastern Alpine lineage, resulting in a marked diversity loss in the Southern Carpathians. The main divergence within the group, separating the ancestor of the two endemic species from R. alpestris s. str., predates the Quaternary. Therefore, range shifts produced by palaeoclimatic oscillations seem to have acted on the genetic structure of R. alpestris group on a more regional level, e.g. triggering an allopatric separation of R. traunfellneri from R. bilobus.
Phylogeography of Pinus tabulaeformis Carr. (Pinaceae), a dominant species of coniferous forest in northern China
Authors: CHEN KANGMING , ABBOTT RICHARD J. , MILNE RICHARD I. , TIAN XIN‐MIN , LIU JIANQUAN 
Published: August 2008

AbstractHow coniferous trees in northern China changed their distribution ranges in response to Quaternary climatic oscillations remains largely unknown. Here we report a study of the phylogeography of Pinus tabulaeformis, an endemic and dominant species of coniferous forest in northern China. We examined sequence variation of maternally inherited, seed‐dispersed mitochondrial DNA (mtDNA) (nad5 intron 1 and nad4/3–4) and paternally inherited, pollen‐ and seed‐dispersed chloroplast DNA (cpDNA) (rpl16 and trnS‐trnG) within and among 30 natural populations across the entire range of the species. Six mitotypes and five chlorotypes were recovered among 291 trees surveyed. Population divergence was high for mtDNA variation (GST = 0.738, NST = 0.771) indicating low levels of seed‐based gene flow and significant phylogeographical structure (NST > GST, P < 0.05). The spatial distribution of mitotypes suggests that five distinct population groups exist in the species: one in the west comprising seven populations, a second with a north–central distribution comprising 15 populations, a third with a southern and easterly distribution comprising five populations, a fourth comprising one central and one western population, and a fifth comprising a single population located in the north‐central part of the species’ range. Each group apart from the fourth group is characterized by a distinct mitotype, with other mitotypes, if present, occurring at low frequency. It is suggested, therefore, that most members of each group apart from Group 4 are derived from ancestors that occupied different isolated refugia in a previous period of range fragmentation of the species, possibly at the time of the Last Glacial Maximum. Possible locations for these refugia are suggested. A comparison of mitotype diversity between northern and southern subgroups within the north‐central group of populations (Group 2) showed much greater uniformity in the northern part of the range both within and between populations. This could indicate a northward migration of the species from a southern refugium in this region during the postglacial period, although alternative explanations cannot be ruled out. Two chlorotypes were distributed across the geographical range of the species, resulting in lower levels of among‐population chlorotype variation. The geographical pattern of variation for all five chlorotypes provided some indication of the species surviving past glaciations in more than one refugium, although differentiation was much less marked, presumably due to the greater dispersal of cpDNA via pollen.
mRNA processing by RNases J1 and J2 affects Bacillus subtilis gene expression on a global scale
Authors: Mäder Ulrike , Zig Léna , Kretschmer Julia , Homuth Georg , Putzer Harald 
Published: August 2008

SummaryRibonucleases J1 and J2 of Bacillus subtilis are evolutionarily conserved enzymes combining an endoribonucleolytic and a 5′−3′ exoribonucleolytic activity in a single polypeptide. Their endoribonucleolytic cleavage specificity resembles that of RNase E, a key player in the processing and degradation of RNA in Escherichia coli. The biological significance of the paralogous RNases J1 and J2 in Bacillus subtilis is still unknown. Based on the premise that cleavage of an mRNA might alter its stability and hence its abundance, we have analysed the transcriptomes and proteomes of single and double mutant strains. The absence or decrease of both RNases J1 and J2 together profoundly alters the expression level of hundreds of genes. By contrast, the effect on global gene expression is minimal in single mutant strains, suggesting that the two nucleases have largely overlapping substrate specificities. Half‐life measurements of individual mRNAs show that RNases J1/J2 can alter gene expression by modulating transcript stability. The absence/decrease of RNases J1 and J2 results in similar numbers of transcripts whose abundance is either increased or decreased, suggesting a complex role of these ribonucleases in both degradative and regulatory processing events that have an important impact on gene expression.
Mutation in the LPS outer core biosynthesis gene, galU, affects LPS interaction with the RTX toxins ApxI and ApxII and cytolytic activity of Actinobacillus pleuropneumoniae serotype 1
Authors: Ramjeet Mahendrasingh , Cox Andrew D. , Hancock Mark A. , Mourez Michael , Labrie Josée , Gottschalk Marcelo , Jacques Mario 
Published: August 2008

SummaryLipopolysaccharides (LPS) and Apx toxins are major virulence factors of Actinobacillus pleuropneumoniae, a pathogen of the respiratory tract of pigs. Here, we evaluated the effect of LPS core truncation in haemolytic and cytotoxic activities of this microorganism. We previously generated a highly attenuated galU mutant of A. pleuropneumoniae serotype 1 that has an LPS molecule lacking the GalNAc‐Gal II‐Gal I outer core residues. Our results demonstrate that this mutant exhibits wild‐type haemolytic activity but is significantly less cytotoxic to porcine alveolar macrophages. However, no differences were found in gene expression and secretion of the haemolytic and cytotoxic toxins ApxI and ApxII, both secreted by A. pleuropneumoniae serotype 1. This suggests that the outer core truncation mediated by the galU mutation affects the toxins in their cytotoxic activities. Using both ELISA and surface plasmon resonance binding assays, we demonstrate a novel interaction between LPS and the ApxI and ApxII toxins via the core oligosaccharide. Our results indicate that the GalNAc‐Gal II‐Gal I trisaccharide of the outer core is fundamental to mediating LPS/Apx interactions. The present study suggests that a lack of binding between LPS and ApxI/II affects the cytotoxicity and virulence of A. pleuropneumoniae.
Polymorphisms within PfMDR1 alter the substrate specificity for anti‐malarial drugs inPlasmodium falciparum
Authors: Sanchez Cecilia P. , Rotmann Alexander , Stein Wilfred D. , Lanzer Michael 
Published: August 2008

SummaryResistance to several anti‐malarial drugs has been associated with polymorphisms within the P‐glycoprotein homologue (Pgh‐1, PfMDR1) of the human malaria parasitePlasmodium falciparum. Pgh‐1, coded for by the genepfmdr1, is predominately located at the membrane of the parasite's digestive vacuole. How polymorphisms within this transporter mediate alter anti‐malarial drug responsiveness has remained obscure. Here we have functionally expressedpfmdr1inXenopus laevisoocytes. Our data demonstrate that Pgh‐1 transports vinblastine, an established substrate of mammalian MDR1, and the anti‐malarial drugs halofantrine, quinine and chloroquine. Importantly, polymorphisms within Pgh‐1 alter the substrate specificity for the anti‐malarial drugs. Wild‐type Pgh‐1 transports quinine and chloroquine, but not halofantrine, whereas polymorphic Pgh‐1 variants, associated with altered drug responsivenesses, transport halofantrine but not quinine and chloroquine. Our data further suggest that quinine acts as an inhibitor of Pgh‐1. Our data are discussed in terms of the model that Pgh‐1‐mediates, in a variant‐specific manner, import of certain drugs into theP. falciparumdigestive vacuole, and that this contributes to accumulation of, and susceptibility to, the drug in question.
Treatment with pimecrolimus cream 1% clears irritant dermatitis of the periocular region, face and neck
Authors: Mensing C. O. , Mensing C. H. , Mensing H. 
Published: August 2008

AbstractBackground  Irritant dermatitis of the face and neck is particularly prevalent in women ≥ 30 years old, who typically present with periocular cutaneous symptoms. Current therapies are limited, indicating a need for rapid, effective alternatives. Pimecrolimus cream 1%, a nonsteroid, cell‐selective inhibitor of inflammatory‐cytokine release, is effective in the treatment of inflammatory skin diseases, such as chronic irritant dermatitis of the hands, and thus offers a potential therapeutic option for this indication. This study reports on the safety and efficacy of pimecrolimus treatment in patients with irritant periocular dermatitis, extending to the face and neck in some patients.Methods  Twenty‐seven patients with periocular irritant dermatitis (extending onto the face and neck in eight) were treated twice daily with pimecrolimus cream 1% for 7 d, followed by once‐daily application for a further 7 d. Erythema, swelling, and pruritus were assessed at baseline, weeks 1–4 using a 4‐point clinical score (0, absent; 1, mild; 2, moderate; and 3, severe).Results  All patients showed marked improvement within 2–3 d of treatment with disease clearance in 23 of 27 patients within 14 d. In the remaining four patients, mild relapse occurred at weeks 3–4, but improvement was observed following a further 10‐d treatment. Side‐effects were mild and transient.Conclusion  Pimecrolimus cream 1% provides a new potential option for treatment of irritant dermatitis of the periocular region, head and neck. Further double‐blind, controlled studies are required to confirm the efficacy and safety of pimecrolimus cream 1% for this indication.
Pyoderma gangrenosum following isotretinoin therapy for acne nodulocystic
Authors: Paula Tinoco Maria , Tamler Carla , Maciel Gustavo , Soares Deborah , Carlos Avelleira João , Azulay David 
Published: August 2008

AbstractA 19‐year‐old man with nodulocystic acne on baseline was treated with isotretinoin therapy. After 1 month on the medication, he developed pyoderma gangrenosum on his pubis area, arms and legs, and pathergy on a puncture site. Possible underlying diseases were excluded. The patient was started on steroids (prednisone 1 mg/kg/d) and isotretinoin therapy was withdrawn. Later the prednisone was tappered and dapsone 100 mg/daily was initiated. After 10 months of follow‐up all lesions had healed and no underlying diseases developed.
Clinical features of cutaneous and disseminated cutaneous leishmaniasis caused by Leishmania (Viannia) braziliensis in Paraty, Rio de Janeiro
Authors: Vieira‐Gonçalves Ricardo , Pirmez Claude , Jorge Maria Eugenia , Souza Wilson Jacinto Silva , Oliveira Márcia Pereira , Rutowitsch Marcio S. , Da‐Cruz Alda Maria 
Published: August 2008

AbstractBackground  American tegumentary leishmaniasis (ATL) caused by Leishmania (Viannia) braziliensis is endemic in Rio de Janeiro State (RJ), where the disease shows epidemiologic and clinical characteristics distinct from those of ATL in other Brazilian regions. Paraty is the second most important endemic area in RJ; however, reports on leishmaniasis in this region refer to the occurrence of the disease without describing its characteristics.Methods  The clinical features of 71 cases of ATL reported between 1991 and 1997 in Paraty are presented. Thirty patients were re‐evaluated 10 years later.Results  Males and females were affected in similar proportions, and the disease was more prevalent in patients aged between 10 and 49 years (63.4%). Cutaneous leishmaniasis was the most prevalent clinical form observed. Unique lesions were present in 69% of cases, 91.6% of which displayed an ulcerated aspect. Although mucosal leishmaniasis was not observed, severe clinical manifestations, such as disseminated cutaneous lesions caused by L. braziliensis, were diagnosed in two patients. These patients presented skin lesions with different clinical aspects spread throughout the body, as well as low cellular immune responses. Montenegro skin test (92% positivity) and serology (8% IgM and 56% IgG anti‐Leishmania positive results) were the most utilized tests for supporting the diagnosis of leishmaniasis. Parasites, detected in 27 of the 33 cases analyzed, were characterized as L. braziliensis.Conclusion  ATL in Paraty shares the clinical and laboratory characteristics reported for ATL in other regions of RJ, probably because of the similar epidemiologic context related to the Atlantic rainforest region.
Skin manifestations of rheumatoid arthritis: a study of 215 Turkish patients
Authors: Ergun Tulin , Inanc Nevsun , Tuney Davut , Kotiloglu Esin Karaa , Seckin Dilek , Tetik Cihangir , Direskeneli Haner 
Published: August 2008

AbstractObjective  To investigate the frequency and clinicopathological features of skin involvement in rheumatoid arthritis (RA), to find out whether early and aggressive disease‐modifying treatment is changing the spectrum towards a milder disease pattern.Methods  Two hundred and fifteen consecutive RA patients were enrolled. Main outcome measures were the frequency of cutaneous features and their relation to disease severity and treatment modality, ultrasound (USG) examination of nodules, histopathological examination of nodules and papules.Results  Mean age and disease duration were 55.3 years and 138.1 months, respectively. Sixty‐six percent of the patients had erosive disease, 70% were rheumatoid factor (RF) positive and 44% had Classes III and IV functional index. Among 43 patients having nodules, 20 were diagnosed as rheumatoid nodules (RNs) and the others as synovitis, bursitis, and so on, on clinical basis and by ultrasound. In 7 of 20 RNs, diagnosis was confirmed by histopathological examination. When clinical, histopathological, and USG data were analyzed collectively, sensitivity, and specifity of USG were found as 100 and 75%, respectively. Sixteen patients had relevant papular lesions. Fourteen of these were diagnosed as palisading neutrophilic granulomatous dermatitis (PNGD) and two as rheumatoid neutrophilic dermatitis (RND) on histopathological examination. Accelerated nodulosis was seen in one, and vasculitis in two of the patients.Conclusions  We observed a milder disease pattern compared to Anglo‐Saxon countries with lower RN and vasculitis frequency. This cannot be explained by early and aggressive treatment as disease onset to treatment interval was long in our patient group. PNGD resembles RN in terms of frequency and association with severe disease.
Non‐melanoma skin cancer and its risk factors in an Austrian population of heart transplant recipients receiving induction therapy
Authors: Geusau Alexandra , Dunkler Daniela , Messeritsch Eva , Sandor Nicolaus , Heidler Gudrun , Rödler Suzanne , Ankersmit Jan , Zuckermann Andreas , Tschachler Erwin 
Published: August 2008

AbstractBackground  Solid organ transplant recipients have a high risk of developing nonmelanoma skin cancers (NMSC). We describe the characteristics and incidence of skin tumors in an Austrian population of heart transplant recipients (HTR).Methods  Three hundred and twenty‐two HTR out of 970 who had received their organ between December 1984 and July 2003 were analyzed for NMSC. Factors associated with tumor development including the different immunosuppressive (IS) modalities were evaluated. Besides triple combination immunosuppressive therapy, all allograft recipients had received induction therapy either with antithymocyte globulin, OKT3 or monoclonal anti‐IL‐2 receptor antibodies.Results  Median post‐transplant follow‐up for all patients was 74.18 months (minimum: 2.6, maximum: 224.8). The median time from transplantation until the excision of the first NMSC was 79.57 months (minimum: 2.69, maximum: 192.8). A total of 263 NMSC were excised in 73 patients. The cumulative incidence of developing a skin tumor increased from 7.3% after 5 years to 26.9% after 10 years and to 56.5% after 15 years. Older age at transplantation (P < 0.0001) and the presence of pre‐cancerous skin conditions (P < 0.0001) were associated with an increased occurrence of NMSC. No significant difference in NMSC incidence was found when the different IS therapies were compared.Conclusions  The cumulative incidence of NMSC in our cohort of HTR is comparable to published data on HTR adjusted according to the geographic location. Transplant patients with clinical evidence of pre‐cancerous skin conditions have a higher degree of susceptibility for the development of NMSC and require particular dermatologic care.
Cutaneous pustular manifestations associated with disseminated septic embolism due to a Panton‐Valentine leukocidin‐producing strain of community‐acquired methicillin‐resistant Staphylococcus aureus
Authors: Wu Chang‐Teng , Lin Jainn‐Jin , Hsia Shao‐Hsuan 
Published: August 2008

AbstractWe report a 12‐year‐old child presented with cutaneous pustular lesions. The lesions are associated with disseminated septic embolism due to Community‐acquired methicillin‐resistant Staphylococcus aureus (CA‐MRSA). The mortality of CA‐MRSA sepsis associated with cutaneous findings is high. In areas where CA‐MRSA is endemic, empiric treatment of suspected cutaneous manifestations should include antibiotics predictably active against this pathogen.