bluuebunny/crossref_metadata_2025_split huggingface dataset:
Review series on helminths, immune modulation and the hygiene hypothesis: Mechanisms underlying helminth modulation of dendritic cell function
Authors: Carvalho Lucas , Sun Jie , Kane Colleen , Marshall Fraser , Krawczyk Connie , Pearce Edward J. 
Published: December 2008

SummaryDendritic cells (DCs) play a central role in activating CD4 T (T helper, Th) cells. As a component of their response to pathogen‐associated stimuli, DCs produce cytokines and express surface molecules that provide important cues to modulate the effector functions of responding Th cells. Much is known of how DCs respond to, and influence immune response outcome to, bacterial and viral pathogens. However, relatively little is understood about how DCs respond to helminth parasites. This is an area of considerable interest since it impacts our understanding of the initiation of Th2 responses, which are stereotypically associated with helminth infections, and the regulation of allergic and autoimmune pathologies which evidence suggests are less severe or absent in individuals infected with helminths. This review attempts to summarize our understanding of the effects of helminth products on dendritic cell biology.
Review series on helminths, immune modulation and the hygiene hypothesis: Immunity against helminths and immunological phenomena in modern human populations: coevolutionary legacies?
Authors: Jackson Joseph A. , Friberg Ida M. , Little Susan , Bradley Janette E. 
Published: December 2008

SummaryAlthough the molecules and cells involved in triggering immune responses against parasitic worms (helminths) remain enigmatic, research has continued to implicate expansions of T‐helper type 2 (Th2) cells and regulatory T‐helper (Treg) cells as a characteristic response to these organisms. An intimate association has also emerged between Th2 responses and wound‐healing functions. As helminth infections in humans are associated with a strong Th2/Treg immunoregulatory footprint (often termed a ‘modified Th2’ response), plausible links have been made to increased susceptibility to microbial pathogens in helminth‐infected populations in the tropics and to the breakdowns in immunological control (allergy and autoimmunity) that are increasing in frequency in helminth‐free developed countries. Removal of helminths and their anti‐inflammatory influence may also have hazards for populations exposed to infectious agents, such as malaria and influenza, whose worst effects are mediated by excessive inflammatory reactions. The patterns seen in the control of helminth immunity are discussed from an evolutionary perspective. Whilst an inability to correctly regulate the immune system in the absence of helminth infection might seem highly counter‐adaptive, the very ancient and pervasive relationship between vertebrates and helminths supports a view that immunological control networks have been selected to function within the context of a modified Th2 environment. The absence of immunoregulatory stimuli from helminths may therefore uncover maladaptations that were not previously exposed to selection.
Widespread mito‐nuclear discordance with evidence for introgressive hybridization and selective sweeps in Lycaeides
Authors: GOMPERT ZACHARIAH , FORISTER MATTHEW L. , FORDYCE JAMES A. , NICE CHRIS C. 
Published: December 2008

AbstractWe investigated the extent and potential cause(s) of mitochondrial introgression within the polytypic North American Lycaeides species complex (Lepidoptera). By comparing population genetic structure based on mitochondrial DNA (COI and COII) and nuclear DNA (251 polymorphic amplified fragment length polymorphism markers), we detected substantial mito‐nuclear discordance, primarily involving a single mitochondrial haplotype (h01), which is likely due to mitochondrial introgression between differentiated Lycaeides populations and/or species. We detected reduced mitochondrial genetic diversity relative to nuclear genetic diversity in populations where mitochondrial haplotype h01 occurs, suggesting that the spread of this haplotype was facilitated by selection. We found no evidence that haplotype h01 is associated with increased fitness (in terms of survival to eclosion, fresh adult weight, and adult longevity) in a polymorphic Lycaeides melissa population. However, we did find a positive association between mitochondrial haplotype h01 and infection by the endoparasitic bacterium Wolbachia in one out of three lineages tested. Linkage disequilibrium between mitochondrial haplotype h01 and Wolbachia infection status may have resulted in indirect selection favouring the spread of haplotype h01 in at least one lineage of North American Lycaeides. These results illustrate the potential for introgressive hybridization to produce substantial mito‐nuclear discordance and demonstrate that an individual's mitochondrial and nuclear genome may have strikingly different evolutionary histories resulting from non‐neutral processes and intrinsic differences in the inheritance and biology of these genomes.
Polymorphic MHC loci in an asexual fish, the amazon molly (Poecilia formosa; Poeciliidae)
Authors: SCHASCHL HELMUT , TOBLER MICHAEL , PLATH MARTIN , PENN DUSTIN J. , SCHLUPP INGO 
Published: December 2008

AbstractGenes of the major histocompatibility complex (MHC) encode molecules that control immune recognition and are highly polymorphic in most vertebrates. The remarkable polymorphisms at MHC loci may be maintained by selection from parasites, sexual selection, or both. If asexual species show equal (or higher) levels of polymorphisms at MHC loci as sexual ones, this would mean that sexual selection is not necessary to explain the high levels of diversity at MHC loci. In this study, we surveyed the MHC diversity of the asexual amazon molly (Poecilia formosa) and one of its sexual ancestors, the sailfin molly (P. latipinna), which lives in the same habitat. We found that the asexual molly has polymorphic MHC loci despite its clonal reproduction, yet not as polymorphic as the sexual species. Although the nucleotide diversity was similar between the asexual and sexual species, the sexual species exhibited a greater genotypic diversity compared to the asexual one from the same habitats. Within‐genome diversity was similar for MHC class I loci, but for class IIB, the sexual species had higher diversity compared to the asexual — despite the hybrid origins and higher levels of heterozygosity at microsatellite loci in the asexual species. The level of positive selection appears to be similar between the two species, which suggests that these polymorphisms are maintained by selection. Thus, our findings do not allow us to rule out the sexual selection hypothesis for the evolution of MHC diversity, and although the sexual fish has higher levels of MHC‐diversity compared to the asexual species, this may be due to differences in demography, parasites, or other factors, rather than sexual selection.
Lineage diversification and historical demography of a sky island salamander,Plethodon ouachitae, from the Interior Highlands
Authors: SHEPARD DONALD B. , BURBRINK FRANK T. 
Published: December 2008

AbstractSky islands provide ideal opportunities for understanding how climatic changes associated with Pleistocene glacial cycles influenced species distributions, genetic diversification, and demography. The salamanderPlethodon ouachitaeis largely restricted to high‐elevation, mesic forest on six major mountains in the Ouachita Mountains. Because these mountains are separated by more xeric, low‐elevation valleys, the salamanders appear to be isolated on sky islands where gene flow among populations on different mountains may be restricted. We used DNA sequence data along with ecological niche modelling and coalescent simulations to test several hypotheses related to diversifications in sky island habitats. Our results revealed thatP. ouachitaeis composed of seven well‐supported lineages structured across six major mountains. The species originated during the Late Pliocene, and lineage diversification occurred during the Middle Pleistocene in a stepping stone fashion with a cyclical pattern of dispersal to a new mountain followed by isolation and divergence. Diversification occurred primarily on an east–west axis, which is likely related to the east–west orientation of the Ouachita Mountains and the more favourable cooler and wetter environmental conditions on north slopes compared to south‐facing slopes and valleys. All non‐genealogical coalescent methods failed to detect significant population expansion in any lineages. Bayesian skyline plots showed relatively stable population sizes over time, but indicated a slight to moderate amount of population growth in all lineages starting approximately 10 000–12 000 years ago. Our results provide new insight into sky island diversifications from a previously unstudied region, and further demonstrate that climatic changes during the Pleistocene had profound effects on lineage diversification and demography, especially in species from environmentally sensitive habitats in montane regions.
Phylogeographical analyses reveal global migration patterns of the barley scald pathogen Rhynchosporium secalis
Authors: ZAFFARANO PASCAL L. , MCDONALD BRUCE A. , LINDE CELESTE C. 
Published: December 2008

AbstractA phylogeographical analysis of the scald pathogen Rhynchosporium secalis was conducted using nuclear DNA sequences from two neutral restriction fragment length polymorphism loci and the mating‐type idiomorphs. Approximately 500 isolates sampled from more than 60 field populations from five continents were analysed to infer migration patterns and the demographic history of the fungus. Migration rates among continents were generally low, consistent with earlier reports of significant population subdivision among continents. Northern Europe was mainly a source population for global migration. We hypothesize that the pathogen only recently moved out of its centre of origin, resulting in founder populations that are reproductively isolated due to the contemporary absence of long‐distance gene flow.
Extensive pollen flow in two ecologically contrasting populations of Populus trichocarpa
Authors: SLAVOV G. T. , LEONARDI S. , BURCZYK J. , ADAMS W. T. , STRAUSS S. H. , DIFAZIO S. P. 
Published: December 2008

AbstractPollen‐mediated gene flow was measured in two populations of black cottonwood using direct (paternity analysis) and indirect (correlated paternity) methods. The Marchel site was an area with an approximate radius of 250 m in a large continuous stand growing in a mesic habitat in western Oregon. In contrast, the Vinson site was an area with a radius of approximately 10 km and consisted of small, disjunct and isolated stands in the high desert of eastern Oregon. Pollen immigration was extensive in both populations, and was higher in the Marchel site (0.54 ± 0.02) than in the substantially larger and more isolated Vinson site (0.32 ± 0.02). Pollen pool differentiation among mothers was approximately five times stronger in the Vinson population (ΦFT = 0.253, N = 27 mothers) than in the Marchel population (ΦFT = 0.052, N = 5 mothers). Pollen dispersal was modelled using a mixed dispersal curve that incorporated pollen immigration. Predicted pollination frequencies generated based on this curve were substantially more accurate than those based on the widely used exponential power dispersal curve. Male neighbourhood sizes (sensu Wright 1946) estimated using paternity analysis and pollen pool differentiation were remarkably similar. They were three to five times smaller in the Vinson population, which reflected the substantial ecological and demographic differences between the two populations. When the same mathematical function was used, applying direct and indirect methods resulted in similar pollen dispersal curves, thus confirming the value of indirect methods as a viable lower‐cost alternative to paternity analysis.
Breeding system, colony and population structure in the weaver antOecophylla smaragdina
Authors: SCHLÜNS E.A. , WEGENER B.J. , SCHLÜNS H. , AZUMA N. , ROBSON S. K. A. , CROZIER R. H. 
Published: December 2008

AbstractWeaver ants (Oecophylla smaragdina) are dominant ants in open forests from India, Australia, China and Southeast Asia, whose leaf nests are held together with larval silk. The species, together with its sole congenerO. longinoda, has been important in research on biological control, communication, territoriality and colony integration. Over most of the range, only one queen has been found per colony, but the occurrence of several queens per nest has been reported for the Australian Northern Territory. The number of males mating with each queen is little known. Here we report on the colony structure ofO. smaragdinausing published and new microsatellite markers. Worker genotype arrays reflect the occurrence of habitual polygyny (more than one queen per colony) in 18 colonies from Darwin, Northern Australia, with up to five queens inferred per colony. Monogyny (one queen per colony) with occasional polygyny was inferred for 14 colonies from Queensland, Australia, and 20 colonies from Java, Indonesia. Direct genotyping of the sperm carried by 77 Queensland queens and worker genotypic arrays of established colonies yielded similar results, indicating that less than half of the queens mate only once and some mate up to five times. Worker genotype arrays indicated that queens from Java and the Northern Territory also often mate with more than one male, but less often than those from Queensland. A strong isolation‐by‐distance effect was found for Queensland samples. The variation uncovered means thatO. smaragdinais a more versatile study system than previously supposed.
Characterization of IRX10 and IRX10‐like reveals an essential role in glucuronoxylan biosynthesis in Arabidopsis
Authors: Brown David M. , Zhang Zhinong , Stephens Elaine , Dupree Paul , Turner Simon R. 
Published: December 2008

SummaryXylan, the major hemicellulosic polysaccharide in Arabidopsis secondary cell walls, requires a number of glycosyltransferases (GT) to catalyse formation of the various glycosidic linkages found in the polymer. In this study, we characterized IRX10 and IRX10‐like (IRX10‐L), two highly homologous genes encoding members of the glycosyltransferase family 47 (GT47). T‐DNA insertions in IRX10 gave a mild irregular xylem (irx) phenotype consistent with a minor defect in secondary cell‐wall synthesis, whereas plants containing mutations in IRX10‐L showed no change. However, irx10 irx10‐L double mutant plants showed a much more severe irx and whole‐plant phenotype, suggesting considerable functional redundancy between these two genes. Detailed biochemical analysis of the irx10 irx10‐L double mutant showed a large reduction of xylan in the secondary cell walls, consistent with a specific defect in xylan biosynthesis. Furthermore, the irx10 irx10‐L mutant retains the unique oligosaccharide found at the reducing end of Arabidopsis xylan, but shows a severe reduction in β(1,4) xylosyltransferase activity. These characteristics are similar to those of irx9 and irx14, mutants that are believed to be defective in xylan chain elongation, and suggests that IRX10 and IRX10‐L also play a role in elongation of the xylan backbone.
A mutation in THERMOSENSITIVE MALE STERILE 1, encoding a heat shock protein with DnaJ and PDI domains, leads to thermosensitive gametophytic male sterility in Arabidopsis
Authors: Yang Ke‐Zhen , Xia Chuan , Liu Xiao‐Lei , Dou Xiao‐Ying , Wang Wei , Chen Li‐Qun , Zhang Xue‐Qin , Xie Li‐Fen , He Luyan , Ma Xuan , Ye De 
Published: December 2008

SummaryIn most flowering plant species, pollination and fertilization occur during the hot summer, so plants must have evolved a mechanism that ensures normal growth of their pollen tubes at high temperatures. Despite its importance to plant reproduction, little is known about the molecular basis of thermotolerance in pollen tubes. Here we report the identification and characterization of a novel Arabidopsis gene, THERMOSENSITIVE MALE STERILE 1 (TMS1), which plays an important role in thermotolerance of pollen tubes. TMS1 encodes a Hsp40‐homologous protein with a DnaJ domain and an a_ERdj5_C domain found in protein disulfide isomerases (PDI). Purified TMS1 expressed in Escherichia coli (BL21 DE3) had the reductive activity of PDI. TMS1 was expressed in pollen grains, pollen tubes and other vegetative tissues, including leaves, stems and roots. Heat shock treatment at 37°C increased its expression levels in growing pollen tubes as well as in vegetative tissues. A knockout mutation in TMS1 grown at 30°C had greatly retarded pollen tube growth in the transmitting tract, resulting in a significant reduction in male fertility. Our study suggests that TMS1 is required for thermotolerance of pollen tubes in Arabidopsis, possibly by functioning as a co‐molecular chaperone.
Metabolic and productive response to ruminal protein degradability in early lactation cows fed untreated or xylose‐treated soybean meal‐based diets
Authors: Jahani‐Moghadam M. , Amanlou H. , Nikkhah A. 
Published: December 2008

SummaryEffects of different dietary rumen undegradable (RUP) to degradable (RDP) protein ratios on ruminal nutrient degradation, feed intake, blood metabolites and milk production were determined in early lactation cows. Four multiparous (43 ± 5 days in milk) and four primiparous (40 ± 6 days in milk) tie‐stall‐housed Holstein cows were used in a duplicated 4 × 4 Latin square design with four 21‐day periods. Each period had 14‐day of adaptation and 7‐day of sampling. Diets contained on a dry matter (DM) basis, 23.3% alfalfa hay, 20% corn silage and 56.7% concentrate. Cows were first offered alfalfa hay at 7:00, 15:00 and 23:00 hours, and 30 min after each alfalfa hay delivery were offered a mixture of corn silage and concentrate. Treatments were diets with RUP:RDP ratios of (i) 5.2:11.6 (control), (ii) 6.1:10.6, (iii) 7.1:9.5 and (iv) 8.1:8.5, on a dietary DM% basis. Different RUP:RDP ratios were obtained by partial and total replacement of untreated soybean meal (SBM) with xylose‐treated SBM (XSBM). In situ study using three rumen‐cannulated non‐lactating cows showed that DM and crude protein (CP) of SBM had greater rapidly degradable fractions. The potentially degradable fractions were degraded more slowly in XSBM. Treatment cows produced greater milk, protein, lactose, solids‐non‐fat and total solids than control cows. Increasing RUP:RDP reduced blood urea linearly. Feed costs dropped at RUP:RDP ratios of 6.1:10.6 and 7.1:9.5, but not at 8.1:8.5, compared with the 5.2:11.6 ratio. Intake of DM and CP, rumen pH, blood glucose, albumin and total protein, faecal and urine pH, changes in body weight and body condition score, and milk lactose and solids‐non‐fat percentages did not differ among treatments. Results provide evidence that increasing dietary RUP:RDP ratio from 5.2:11.6 to 7.1:9.5 optimizes nitrogen metabolism and milk production and reduces feed costs in early lactation cows. Reduced blood urea suggests reprodutive benefits.
Urothelial and incidental prostate carcinoma in prostates from cystoprostatectomies for bladder cancer: is there a relationship between urothelial and prostate cancer?
Authors: Barbisan Francesca , Mazzucchelli Roberta , Scarpelli Marina , Lopez‐Beltran Antonio , Cheng Liang , Kirkali Ziya , Montironi Rodolfo 
Published: December 2008

OBJECTIVETo determine the incidence and features of urothelial carcinoma (UC) involving the prostate (UCP) and of prostate adenocarcinoma (PA) in radical cystoprostatectomy (RCP) for bladder cancer.PATIENTS AND METHODSThe whole‐mount prostate sections of 248 RCP consecutively examined from 1995 to 2007 were reviewed to determine the incidence and features of UCP and PA. UCP was separately evaluated for UC originating from the urethra and peri‐urethral ducts (PUC) and for direct extension of bladder UC.RESULTSThere was UCP in 94 (37.9%) of 248 patients, whereas PUC was present in 78 (31.5%). UC in situ and noninvasive papillary PUC was present in 42 (53.9%) of the 78, whereas stromal invasion was present in 36 (46.1%). Direct extension of UC from the bladder only was present in 16 (6.5%) patients. PA was present in 123 (49.6%) of 248 patients; 96 (78.1%) were in the peripheral zone. In 107 patients (87%) the Gleason score was ≤6; 96 (78.1%) were pT2a, with a lower frequency in other pT categories. The margins were negative in 96.7% of cases. All patients were pN0 for PA; in 116 (95.1%) the volume was <0.5 mL. Of the 123 patients with incidental prostate cancer, 100 cancers (81.3%) were considered clinically insignificant. UCP coexisted with PA in 43 (17.3%) of 248 patients, whereas PUC and PA occurred together in the same prostate in 32 (12.9%). Direct extension of UC from the bladder and PA occurred together in the same prostate in 11 (4.4%) patients.CONCLUSIONSUC involving the prostate and PA are present in most RCP specimens. UC can arise from extension of trigonal or bladder‐neck tumours, proximal prostate ducts/urethra, or from cell implantation from manipulation of vesical neoplasms. The frequent high coincidence of prostate and bladder cancer can be explained by a common pathway of carcinogenesis.
Cancer‐specific and non‐cancer‐related mortality rates in European patients with T1a and T1b renal cell carcinoma
Authors: Zini Laurent , Patard Jean‐Jacques , Capitanio Umberto , Crepel Maxime , De La Taille Alexandre , Tostain Jacques , Ficarra Vincenzo , Bernhard Jean‐Christophe , Ferrière Jean‐Marie , Pfister Christian , Villers Arnauld , Montorsi Francesco , Karakiewicz Pierre I. 
Published: December 2008

OBJECTIVETo examine cancer‐specific and non‐cancer‐related mortality rates in 451 patients with T1a–bN0M0 renal cell carcinoma (RCC) treated with either radical or partial nephrectomy (RN or PN) in Europe.PATIENTS AND METHODSBetween 1987 and 2007, 451 patients with T1a–bN0M0 RCC were treated for histologically confirmed RCC with RN or PN at one of seven participating European institutions. The preoperative American Society of Anesthesiology (ASA) score was available for all patients and was used to control for baseline comorbidities. The preoperative glomerular filtration rate (GFR) was estimated using the Modification of Diet in Renal Disease study group equation. We used univariate and multivariate competing‐risks regression analyses to test the effect of the ASA score, GFR, T stage (T1a vs T1b) and nephrectomy type (RN or PN) on RCC‐specific mortality and non‐RCC‐related mortality.RESULTSIn patients with T1a–b RCC cancer‐ specific mortality was unaffected by stage, nephrectomy type or GFR. Conversely, non‐RCC‐related mortality was strongly affected by the ASA score and GFR. Unlike in a previous report, nephrectomy type did not affect non‐RCC‐related mortality. This lack of significance relative to RN may stem from the relatively high rate of PN use in the present series.CONCLUSIONPN or RN virtually eliminate the risk of cancer‐specific mortality in patients with T1a–b RCC. Poor preoperative ASA score and impaired renal function appear to represent relative contra‐indications to surgical management of T1a–b lesions.