bluuebunny/crossref_metadata_2025 huggingface dataset:
Speciation in reverse: morphological and genetic evidence of the collapse of a three‐spined stickleback (Gasterosteus aculeatus) species pair
Authors: TAYLOR E. B. , BOUGHMAN J. W. , GROENENBOOM M. , SNIATYNSKI M. , SCHLUTER D. , GOW J. L.
Published: November 2005

Historically, six small lakes in southwestern British Columbia each contained a sympatric species pair of three‐spined sticklebacks (Gasterosteus aculeatus). These pairs consisted of a ‘benthic’ and ‘limnetic’ species that had arisen postglacially and, in four of the lakes, independently. Sympatric sticklebacks are considered biological species because they are morphologically, ecologically and genetically distinct and because they are strongly reproductively isolated from one another. The restricted range of the species pairs places them at risk of extinction, and one of the pairs has gone extinct after the introduction of an exotic catfish. In another lake, Enos Lake, southeastern Vancouver Island, an earlier report suggested that its species pair is at risk from elevated levels of hybridization. We conducted a detailed morphological analysis, as well as genetic analysis of variation at five microsatellite loci for samples spanning a time frame of 1977 to 2002 to test the hypothesis that the pair in Enos Lake is collapsing into a hybrid swarm. Our morphological analysis showed a clear breakdown between benthics and limnetics. Bayesian model‐based clustering indicated that two morphological clusters were evident in 1977 and 1988, which were replaced by 1997 by a single highly variable cluster. The most recent 2000 and 2002 samples confirm the breakdown. Microsatellite analysis corroborated the morphological results. Bayesian analyses of population structure in a sample collected in 1994 indicated two genetically distinct populations in Enos Lake, but only a single genetic population was evident in 1997, 2000, and 2002. In addition, genetic analyses of samples collected in 1997, 2000, and 2002 showed strong signals of ‘hybrids’; they were genetically intermediate to parental genotypes. Our results support the idea that the Enos Lake species pair is collapsing into a hybrid swarm. Although the precise mechanism(s) responsible for elevated hybridization in the lake is unknown, the demise of the Enos Lake species pair follows the appearance of an exotic crayfish,Pascifasticus lenisculus, in the early 1990s.
Screening for rapidly evolving genes in the ectomycorrhizal fungusPaxillus involutususing cDNA microarrays
Authors: LE QUÉRÉ ANTOINE , ASTRUP ERIKSEN KASPER , RAJASHEKAR BALAJI , SCHÜTZENDÜBEL ANDRES , CANBÄCK BJÖRN , JOHANSSON TOMAS , TUNLID ANDERS
Published: November 2005

We have examined the variations in gene content and sequence divergence that could be associated with symbiotic adaptations in the ectomycorrhizal fungusPaxillus involutusand the closely related speciesPaxillus filamentosus. Strains with various abilities to form mycorrhizae were analysed by comparative genomic hybridizations using a cDNA microarray containing 1076 putative unique genes ofP. involutus.To screen for genes diverging at an enhanced and presumably non‐neutral rate, we implemented a simple rate test using information from both the variations in hybridizations signal and data on sequence divergence of the arrayed genes relative to the genome ofCoprinus cinereus.C. cinereusis a free‐living saprophyte and is the closest evolutionary relative toP. involutusthat has been fully sequenced. Approximately 17% of the genes investigated were detected as rapidly diverging withinPaxillus. Furthermore, 6% of the genes varied in copy numbers between the analysed strains. Genome rearrangements associated with this variation including duplications and deletions may also play a role in adaptive evolution. The cohort of divergent and duplicated genes showed an over‐representation of either orphans, genes whose products are located at membranes, or genes encoding for components of stress/defence reactions. Some of the identified genomic changes may be associated with the variation in host specificity of ectomycorrhizal fungi. The proposed procedure could be generally applicable to screen for rapidly evolving genes in closely related strains or species where at least one has been sequenced or characterized by expressed sequence tag analysis.
Microsatellite analysis reveals strong but differential impact of a social parasite on its two host species
Authors: FISCHER‐BLASS BIRGIT , HEINZE JÜRGEN , FOITZIK SUSANNE
Published: November 2005

The speed and the dynamics of the co‐evolutionary process strongly depend on the relative strengths of reciprocal selection pressures exerted by the interacting species. Here, we investigate the influence of an obligate social parasite, the slave‐making ant Harpagoxenus sublaevis, on populations of the two main host species Leptothorax acervorum and Leptothorax muscorum from a German ant community. A combination of genetic and demographic data allowed us to analyse the consequences of raiding pressure on the hosts’ life history and possible host preferences of the parasite. We can demonstrate that slave raids during which the social parasite pillages brood from neighbouring host colonies are both frequent and extremely destructive for both host species. Microsatellite analysis showed that, on average, a single slave‐maker colony conducts more than three raids per year and that host colonies mostly perish in the aftermath of these parasite attacks. Only in few cases, surviving nests of previously raided host colonies were found in the surroundings of slave‐maker colonies. As a consequence of the high prevalence of parasites and their recurrent and devastating slave raids on host colonies, the life expectancy of host colonies was severely reduced. Combining our results on host‐specific parasitic colony founding and raiding frequencies with the post‐raid survival rate, we can demonstrate an overall higher mortality rate for the smaller host species L. muscorum. This might be caused by a preference of H. sublaevis for this secondary host species as demographic data on host species usage indicate.
Clonal analysis reveals high rate of structural mutations in fimbrial adhesins of extraintestinal pathogenic Escherichia coli
Authors: Weissman Scott J. , Chattopadhyay Sujay , Aprikian Pavel , Obata‐Yasuoka Mana , Yarova‐Yarovaya Yuliya , Stapleton Ann , Ba‐Thein William , Dykhuizen Daniel , Johnson James R. , Sokurenko Evgeni V.
Published: November 2005

Type 1 fimbriae of Escherichia coli mediate mannose‐specific adhesion to host epithelial surfaces and consist of a major, antigenically variable pilin subunit, FimA, and a minor, structurally conserved adhesive subunit, FimH, located on the fimbrial tip. We have analysed the variability of fimA and fimH in strains of vaginal and other origin that belong to one of the most prominent clonal groups of extraintestinal pathogenic E. coli, comprised of O1:K1‐, O2:K1‐ and O18:K1‐based serotypes. Multiple locus sequence typing (MLST) of this group revealed that the strains have identical (at all but one nucleotide position) eight housekeeping loci around the genome and belong to the ST95 complex defined by the publicly available E. coli MLST database. Multiple highly diverse fimA alleles have been introduced into the ST95 clonal complex via horizontal transfer, at a frequency comparable to that of genes defining the major O‐ and H‐antigens. However, no further significant FimA diversification has occurred via point mutation after the transfers. In contrast, while fimH alleles also move horizontally (along with the fimA loci), they acquire point amino acid replacements at a higher rate than either housekeeping genes or fimA. These FimH mutations enhance binding to monomannose receptors and bacterial tropism for human vaginal epithelium. A similar pattern of rapid within‐clonal structural evolution of the adhesive, but not pilin, subunit is also seen, respectively, in papG and papA alleles of the di‐galactose‐specific P‐fimbriae. Thus, while structurally diverse pilin subunits of E. coli fimbriae are under selective pressure for frequent horizontal transfer between clones, the adhesive subunits of extraintestinal E. coli are under strong positive selection (Dn/Ds > 1 for fimH and papG) for functionally adaptive amino acid replacements.
Phosphorylation and functional analysis of the sporulation initiation factor Spo0A from Clostridium botulinum
Authors: Wörner Kristina , Szurmant Hendrik , Chiang Christina , Hoch James A.
Published: November 2005

The initiation of sporulation in aerobic Bacillus species is regulated by the phosphorelay consisting of several sensor histidine kinases, the Spo0F response regulator, the Spo0B phosphotransferase and the Spo0A transcription factor that upon phosphorylation represses genes for growth and activates the developmental process. Clostridium species lack both Spo0F and Spo0B and the identities of the sensor histidine kinases are unknown. The amino acid sequence of Spo0A is highly conserved in Clostridium botulinum relative to Bacillus subtilis but the cloned C. botulinum Spo0A was unable to complement a spo0A mutant of B. subtilis for sporulation. However, it was able to repress the abrB gene of B. subtilis. Active site mutations in Spo0A still repressed, indicating this activity was independent of phosphorylation. An orphan sensor histidine kinase of C. botulinum appeared to normally phosphorylate C. botulinum Spo0A and expression of this kinase in combination with C. botulinum Spo0A in B. subtilis was lethal, suggesting phosphorylation of C. botulinum Spo0A repressed essential growth genes as a prerequisite to sporulation but could not compensate for this effect by inducing sporulation. A chimera Spo0A consisting of a B. subtilis Spo0A response regulator domain fused to a C. botulinum DNA‐binding domain was capable of restoring sporulation to a spo0A mutant of B. subtilis albeit at less than wild‐type levels. The data suggest that induction of sporulation requires interactions of both domains of Spo0A with other conserved proteins and despite the high conservation of the amino acid sequence of C. botulinum Spo0A, some of these interactions have been lost.
Metabolic regulation of type III secretion gene expression in Pseudomonas aeruginosa
Authors: Rietsch Arne , Mekalanos John J.
Published: November 2005

Type III secretion‐mediated cytotoxicity is one of the key virulence mechanisms of the opportunistic pathogen Pseudomonas aeruginosa. Prior data from several laboratories have established that metabolism is a key factor in the regulation of type III secretion gene expression in P. aeruginosa. Here we use a fluorescence‐activated cell sorter (FACS)‐based approach to investigate expression of type III secretion genes at a single‐cell level. The data demonstrate that the metabolic state regulates the percentage of cells that are able to induce type III secretion gene expression under inducing conditions. We also present evidence that this regulation is the result of an effect of the growth conditions on the ability of P. aeruginosa to assemble a functional type III secretion apparatus. Preliminary data suggest that the metabolite that controls type III secretion gene expression is derived from acetyl‐CoA and that this regulation may, in part, be mediated by changes in the intracellular concentration of cyclic‐AMP.
Synthesis of α‐glucans in fission yeast spores is carried out by three α‐glucan synthase paralogues, Mok12p, Mok13p and Mok14p
Authors: García Ignacio , Tajadura Virginia , Martín Victoria , Toda Takashi , Sánchez Yolanda
Published: November 2005

Fission yeast possesses a family of (1,3)‐α‐glucan synthase‐related genes; one of them, mok1+/ags1+, plays an essential function in morphogenesis during vegetative growth. Here we show that three mok1+ paralogues –mok12+, mok13+ and mok14+– are required for sporulation to succeed, acting at different stages of the spore wall maturation process. Mutation of mok12+ affected the efficiency of spore formation and spore viability. Deletion of mok13+ does not affect spore viability but the spores showed reduced resistance to stress conditions. mok14Δ mutant spores failed to accumulate the amylose‐like spore wall‐specific polymer. mok12+, mok13+ and mok14+ expression was restricted to sporulating cells and the proteins localized to the spore envelope but with different timing. mok11+ was also induced during the sporulation process although its deletion did not show apparently a sporulation defect. In vegetative cells, β‐glucans are more abundant than α‐glucans (55% versus 28%). In spores, the situation was the opposite, α‐glucans accounted for 46% while β‐glucans were approximately 38% of the total polysaccharides. We found at least two types of α‐glucan polymers, Mok12p and Mok13p, were involved in the synthesis of the greater part of α‐glucan in the spores envelope, a polymer that is mainly digested with α‐1,3 glucanase, while Mok14p, homologous to starch synthases, was required for the synthesis of the iodine‐reactive polymer that is made of α‐1,4 glucose residues.
Linkage of dermatomyositis in the Shetland Sheepdog to chromosome 35
Authors: CLARK LEIGH ANNE , CREDILLE KELLY M. , MURPHY KEITH E. , REES CHRISTINE A.
Published: November 2005

Abstract  Dermatomyositis is an inflammatory disease of the skin and muscle and is most commonly found in the Shetland sheepdog. Both the clinical presentation and the age of onset of dermatomyositis vary widely, and the inability to diagnose dermatomyositis before clinical symptoms ensue has made control of the disease difficult. Identification of a genetic marker that cosegregates with dermatomyositis would facilitate the development of a DNA‐based test for the early detection of affected dogs. We report the use of linkage disequilibrium (LD) mapping to identify linkage to phenotypic dermatomyositis in the Shetland sheepdog. One marker, microsatellite marker FH3570 on canine chromosome 35, had evidence of LD (P = 0.00002). Further studies are necessary to narrow the region harbouring the dermatomyositis locus, identify candidate genes and determine mode of inheritance.
Clinical, immunological and histopathological findings in a subpopulation of dogs with pododermatitis
Authors: BREATHNACH RORY M. , BAKER KENNETH P. , QUINN PATRICK J , MCGEADY THOMAS A. , AHERNE CAROL M. , JONES BOYD R.
Published: November 2005

Abstract  Clinical, immunological and histopathological findings in 20 adult dogs of varying breeds with chronic (≥ 6 months) inflammation confined to the pedal skin were compared over a 2‐year period with those of a group of age‐matched controls (n = 20). All affected dogs were pruritic but systemically well. Lesions were present on all four feet in 18/20 cases. Affected feet were characteristically erythematous, swollen, painful and alopecic. Sinus tracts were evident in 4/20 dogs. Despite a methodical series of diagnostic tests, no underlying cause was identified. None of the dogs responded to antimicrobial therapy administered for 8 weeks, none had evidence of ectoparasitism and none satisfied the criteria for atopic dermatitis. There was no response to a dietary trial using a novel protein source. The condition was characterized histopathologically by epidermal hyperplasia, hyperkeratosis, spongiosis, dermal oedema and perivascular aggregates of lymphocytes and plasma cells. Clinical signs did not correlate with histopathological findings. Affected dogs had significantly elevated serum IgG and IgM concentrations. The results of lymphocyte proliferation assays and phenotypic studies to determine the relative percentage of CD3+, CD4+, CD8+ and CD21+ lymphocyte subsets, and the ratio of CD4+/CD8+ cells were not significantly different between groups. No age, sex or seasonal predilections were noted. All dogs subsequently responded to immunosuppressive doses of prednisolone or cyclosporin. The term immunomodulatory‐responsive lymphocytic–plasmacytic pododermatitis is proposed to denote what may be a previously unrecognized condition in some dogs with pododermatitis of undetermined aetiology.
Irrigation and Nutrient Effects on Growth and Water–Yield Relationship of Wheat (Triticum aestivum L.) in Central India
Authors: Mandal K. G. , Hati K. M. , Misra A. K. , Bandyopadhyay K. K. , Mohanty M.
Published: November 2005

Increasing production of wheat from a limited water supply can result from efficient irrigation and nutrient management. A 3‐year field experiment was conducted at the Indian Institute of Soil Science, Bhopal, to study the growth, yield, seasonal evapotranspiration (ET) and water use efficiency (WUE), and the water–yield relationship of wheat in a soybean–wheat cropping system on vertisols. Three levels of irrigation, viz. I0, no post‐sowing irrigation; I1, two irrigations [crown root initiation (CRI) and flowering stage]; and I2, three irrigations (CRI, maximum tillering and flowering stage) and three nutrient management treatments, viz. F0, control (without fertilizer/manure); F1, 100 % NPK (100–21.5–24.9 kg ha−1); and F2, 100 % NPK + farmyard manure (FYM‐10 t ha−1) were tested in a split‐plot design with three replication. It has been established (through anova) that the year effect was rather negligible and the interaction effects of irrigation and nutrient management on the growth parameters, ET, yield components, yield and WUE were significant. Plant height, progressive leaf area index, dry matter accumulation and crop growth rate were higher in I2F2, and I2F1 and I1F2 were statistically at par. The seasonal ET increased significantly with the increase in water supply in every nutrient treatment and it was highest in I2F2 and lowest in I0F0. The highest grain yield was obtained in I2F2; and a similar yield was recorded in I3F1 and I2F2. This shows a strong interaction effect between irrigation and nutrients. Yield components, viz. number of ears m−2, number of grains ear−1 and 1000‐grain weight were significant. The higher number of ears m−2 containing greater number of grains with relatively heavier weights appeared to have contributed to the higher yield in I1F2, I2F1 and I2F2. The highest WUE obtained in I0F2 did not correspond to the highest yield and maximum ET, but a WUE of 10.43 kg ha−1 mm−1 in the I2F2 combination corresponded with the highest yield and the seasonal ET requirement was 391.8, which was 137 % greater than the water use at maximum WUE. The ET–grain yield relationship was linear, with a lowest regression slope (i.e. marginal WUE) and elasticity of water production (Ewp) in F0 and a considerably higher slope and Ewp in F1 and F2. As the Ewp is positive and close to one in 100 % NPK treatment, the scope of improving WUE and yield with only inorganic fertilizer is very little, and relatively greater scope exists in the integrated management of organic manure and inorganic fertilizer. The results suggest that integrated nutrient management (100 % NPK + FYM) in conjunction with three irrigations maximized yield of wheat with concomitant improvement in ET and WUE under limited water availability.
Genotypic Variation in Root Systems of Chickpea (Cicer arietinum L.) across Environments
Authors: Yusuf Ali M. , Johansen C. , Krishnamurthy L. , Hamid A.
Published: November 2005

Root systems of various chickpea genotypes were studied over time and in diverse environments, – varying in soil bulk density, phosphorus (P) levels and moisture regimes. In a pot study comparing a range of chickpea genotypes, ICC 4958 and ICCV 94916‐4 produced higher root length density (RLD) and root dry weight (RDW), which were better expressed under P stress conditions. In two field experiments in soils of intermediate and high soil bulk densities, ICC 4958 also had greater RLD and RDW, particularly under soil moisture stress conditions. The expression of greater rooting ability of ICC 4958 under a wide range of environmental conditions confirms its suitability as a parent for genetically enhancing drought resistance and P acquisition ability. The superiority of ICC 4958 over other genotypes was for root proliferation expressed through RLD. Thus, the variation in RLD can be the most relevant root trait that reflects chickpea's potential for soil moisture or P acquisition.
Nitrogen Accumulation and Translocation for Winter Wheat under Different Irrigation Regimes
Authors: Xu Z. Z. , Yu Z. W. , Wang D. , Zhang Y. L.
Published: November 2005

The translocation of pre‐anthesis nitrogen to the grain is an important source for winter wheat. The relation between the nitrogen translocation and irrigation regime was studied in the field under a rain‐proof trough shelter. Nitrogen (N) translocation amount, N translocation efficiency decreased with a decline in irrigation amount or by excessive irrigation. Compared with different organs, the leaf and stem had higher N translocation amounts, and contributions to grain for both cultivars – Jinan 17 and Lumai 21, indicating that stem also is a major N source for grain development. The contribution of pre‐anthesis total above ground N to grain N ranged from 57 to 76 %, indicating the importance of pre‐anthesis storage of N for achieving high grain N concentrations. Grain nitrogen and yield (kg ha−1) were positively and significantly correlated with the N translocation amounts and contributions, respectively, suggesting that the sink strength may be involved in the translocation of N from a vegetative organ to the grain. N harvest index (NHI) was significantly correlated with N translocation efficiency, suggesting that the latter is a prerequisite for increasing grain N and improving grain quality. The experiment showed that N translocation status is enhanced by better irrigation practices, but limited by severely deficient or excessive irrigation.
Maize Yields as Affected by Short‐ and Long‐Term Improved Fallows: A Comparative Analysis in the Asian Humid Tropics
Authors: Schelbert R. , Sangakkara U. R. , Stamp P.
Published: November 2005

Improved short‐ or long‐term fallows are considered suitable low external input technologies for maintaining productivity and sustainability of tropical smallholder upland cropping units, although comparisons on the benefits of this technology are not widely reported. A field study evaluated the impact of improved short (6 months) and long‐term fallow (18 months) using Crotalaria juncea and Tithonia diversifolia, in relation to a natural fallow of the same durations, on the productivity of maize (Zea mays), the most important upland cereal in tropical Asia, over a minor season. The use of improved fallows, especially Tithonia, increased maize yields over the Crotalaria or natural fallow. While the overall yields of maize after a long fallow were greater, the beneficial impact of the green manures was significantly higher in the short fallows. The causal factors for this trend, including biomass production of the improved fallows and possible impact on soils, along with the greater benefits of short‐term fallows for increasing maize yields in the tropics due to lower requirements of unproductive time are presented.
Effects of repeated low‐dose UVB irradiation on the hyphal growth of Candida albicans
Authors: Brasch J. , Kay C.
Published: November 2005

Ultraviolet B light (UVB) can have negative phototropic effects on fungi. Candida albicans is often found on human skin exposed to UVB. Therefore, it is of medical interest to know whether a negative phototropic response to UVB irradiation can support an invasive growth of this potentially dangerous agent. In our study we investigated how repeated irradiation with low doses of UVB can influence the hyphal growth of C. albicans. Six randomly chosen strains of C. albicans were tested. Formation of hyphae was induced and maintained within transparent agar plates. The fungi were exposed to UVB three times daily for 7 days from either the obverse or the reverse side during incubation. The wavelength spectrum was in the range of 310–315 nm, single doses were between 0.0018 and 0.432 J cm−2. After 7 days the morphology and growth direction of C. albicans cells were determined microscopically. All six strains showed a common and dose‐dependent response to UVB irradiation: the progression of hyphal growth was inhibited, no phototropic effects were seen and as a new finding an increased formation of blastospores was observed. We conclude that an irradiation of human skin colonized by C. albicans with doses of UVB that can occur under natural or artificial conditions is unlikely to trigger skin invasion by C. albicans.
Invasive fungal sinusitis of isolated sphenoid sinus in immunocompetent subjects
Authors: Chopra Hemant , Dua Kapil , Malhotra Vineeta , Gupta Rishi Pal , Puri Harpreet
Published: November 2005

Invasive fungal sinusitis of the paranasal sinuses in a healthy immunocompetent person is uncommon. Isolated involvement of any paranasal sinus, particularly sphenoid sinus is rare. In this study, five immunocompetent patients who had no nasal complaints but obscure symptoms of headache and orbital symptoms such as diplopia, retro‐orbital pain and loss of vision were diagnosed to be having fulminant fungal sinusitis of the sphenoid sinus. Three patients had aspergillosis and two patients had mucormycosis. These patients initially presented to neurologists and ophthalmologists because they had no ENT complaints. The diagnosis was made on endoscopy, radiology and histopathology. They were treated aggressively according to the standard protocols. The purpose of this paper is to bring to light the changing clinical spectrum of invasive fungal sinusitis. It can occur in immunocompetent patients and in the form of isolated sphenoid sinus involvement.
Incubation of human chorioamniotic membranes with Candida albicans induces differential synthesis and secretion of interleukin‐1β, interleukin‐6, prostaglandin E2, and 92 kDa type IV collagenase
Authors: Zaga‐Clavellina Veronica , López Guadalupe García , Estrada‐Gutierrez Guadalupe , Martinez‐Flores Alfonso , Maida‐Claros Rolando , Beltran‐Montoya Jorge , Vadillo‐Ortega Felipe
Published: November 2005

Ascendant colonization of pathogenic microorganisms from the vagina to the uterus is strongly associated to preterm labour and premature rupture of membranes. This study evaluated the secretion of interleukin (IL)‐1β, tumour necrosis factor (TNF)α, IL‐6, prostaglandin E2 (PGE2), and metalloproteinases 9 and 2 by the human chorioamnion stimulated with Candida albicans. Chorioamniotic membranes were obtained after delivery by elective Cesarean section from women at 37–40 weeks of gestation without evidence of active labour. The membranes were mounted in Transwell devices that form two independent compartments, which allow testing the individual responses and contributions of the amnion and choriodecidua. One million CFU ml−1 of C. albicans was added to either the amniotic or choriodecidual surface and secretions of the markers were measured in both compartments using specific enzyme‐linked immunosorbent assay and zymography. Fetal membranes followed different secretion patterns of proinflammatory cytokines depending on the side to which the stimulus was applied. IL‐1β was produced in higher amounts in the presence of C. albicans when applied to the choriodecidual side; TNFα and IL‐6 secretion did not change in either the amnion or choriodecidual region. PGE2 synthesis depicted a different pattern, the amniotic tissue was more responsive than the choriodecidual tissue, and this response tended to be higher even when only the amniotic side was stimulated. Matrix metalloproteinases (MMP)‐9 increased after stimulation, being the choriodecidua its main source. Selective stimulation with C. albicans induced a differential secretion of IL‐1β, PGE2, and MMP‐9, resulting from a cooperative and bidirectional communication between the amnion and the choriodecidua.
Comparison of polar lipids from yeast and mycelial forms of Candida albicans and Candida dubliniensis
Authors: Zarei Mahmoudabadi A. , Drucker D. B.
Published: November 2005

The aim of the present study was to compare polar lipids of yeast and mycelial forms of both Candida albicans and Candida dubliniensis. Cultures were harvested from Lee's medium after incubation at 37 °C for 48 h. Yeast and mycelial forms were washed, separated from one another, dried and lipids extracted and prepared for fast atom bombardment mass spectrometry analysis in the negative‐ion mode. For fatty acids, differences between the yeast and mycelial forms were greater for C. dubliniensis than for C. albicans. For the phospholipid families, phosphatidic acid and phosphatidylethanolamine, differences between yeast and mycelial forms were greater for C. dubliniensis than for C. albicans. For both species, it is concluded that both fatty acid and phospholipid molecular species compositions differ according to whether the cells are in the yeast or mycelial form.
Onychomycosis is no longer a rare finding in children
Authors: Lange M. , Roszkiewicz J. , Szczerkowska‐Dobosz A. , Jasiel‐Walikowska E. , Bykowska B.
Published: November 2005

Onychomycosis was considered uncommon in children. This survey was carried out to estimate the frequency of fungal nail infections in children and adolescents (0–18 years of age) attending our clinic in the last decade and gain more insight into the aetiology and clinics of this entity in the paediatric age group. This study is based on data obtained from 2320 children and adolescents suspected of superficial fungal infection. Onychomycosis was diagnosed in 99 cases, representing 19.8% of all mycologically confirmed superficial mycoses (500 cases) in our material. Fingernail onychomycosis was recognized in 52 (10.4%) cases; children under 3 years of age were predominantly involved. Candida albicans was the most common isolated pathogen. Toenail onychomycosis concerned 47 (9,4%) patients; the incidence increased steadily with increasing age. Trichophyton rubrum was the most common aetiological agent with respect to toenail infection followed by T. mentagrophytesvar. interdigitale and T. mentagrophytes var. granulosum. The majority of fungal nail infections were characterized clinically by distal and lateral subungual onychomycosis. The growing trend towards the frequency of toenail and fingernail onychomycosis in children and adolescents was found in the last decade in north Poland. The results of our study show that onychomycosis in prepubertal children is not exceptional and should be considered in differential diagnosis of nail plate disorders.
Hairy is a cell context signal controlling Notch activity
Authors: Cui Yanzhen
Published: November 2005

Notch signaling regulates cell fate determination and many developmental processes. Here we report that lateral inhibition, a major mechanism for Notch activity, is modulated by Hairy, a bHLH‐WRPW protein. In Xenopus, Notch can have from inhibitory, permissive to enhancing roles in muscle or neural differentiation. These cell context‐dependent effects correlate with Hairy expression levels from high to low, respectively, in the cells. Moreover, Notch effects can be altered upon manipulation of Hairy expression. We propose that Hairy provides a cell context in which a cell can interpret Notch and other extrinsic signals by controlling responsiveness of its target genes; this mode of Hairy–Notch interaction may apply in other systems.
Molecular mechanisms for thyroid hormone‐induced remodeling in the amphibian digestive tract: A model for studying organ regeneration
Authors: Ishizuya‐Oka Atsuko , Shi Yun‐Bo
Published: November 2005

During amphibian metamorphosis the digestive tract is extensively remodeled under the control of epithelial–connective tissue interactions. At the cellular level, larval epithelial cells undergo apoptosis, while a small number of stem cells appear, actively proliferate, and then differentiate to form adult epithelium that is analogous to its mammalian counterpart. Therefore the amphibian digestive tract is a unique model system for the study of postembryonic organ regeneration. As amphibian intestinal remodeling can be triggered by thyroid hormone (TH), the molecular mechanisms involved can be studied from the perspective of examining the expression cascade of TH response genes. A number of these genes have been isolated from the intestine of Xenopus laevis. Recent progress in the functional analysis of this cascade has shed light on key molecules in intestinal remodeling such as matrix metalloproteinase‐11, sonic hedgehog, and bone morphogenetic protein‐4. These genes are also thought to play key roles in organogenesis and/or homeostasis in both chick and mammalian digestive tract, suggesting the existence of conserved mechanisms underlying such events in terrestrial vertebrates. In this article, we review our recent findings in this field, focusing on the development of adult epithelium in the X. laevis intestine.
Pax3 transcripts in melanoblast development
Authors: Blake Judith A. , Ziman Mel R.
Published: November 2005

The transcription factor encoded by PAX3 is among the first expressed in the embryo, with a key role in development of the melanocytic lineage. Re‐expression of PAX3, consistently observed in cutaneous malignant melanoma (CMM) as compared to normal melanocytes, appears linked to progression of CMM. Previous research has identified PAX3d (encoded by exons 1–9) as the predominant isoform present in CMM, together the with an alternate isoform PAX3c (encoded by exons 1–8). We investigated the expression of Pax3c and Pax3d transcripts during mouse development. The reverse transcription–polymerase chain reaction and immunohistochemistry experiments presented here implicate these transcripts in melanoblast development and demonstrate significant spatial and temporal differences in their expression. Differences in expression were also noted during active hair regrowth in adult skin, which is accompanied by proliferation and migration of melanoblasts into the hair cortex to color new hair. Results indicate that the defined spatial and temporal expression of Pax3d may be linked to either melanoblast proliferation or migration during melanogenesis.
GATA factors as key regulatory molecules in the development of Drosophila endoderm
Authors: Murakami Ryutaro , Okumura Takashi , Uchiyama Hideho
Published: November 2005

Essential roles for GATA factors in the development of endoderm have been reported in various animals. A Drosophila GATA factor gene, serpent (srp, dGATAb, ABF), is expressed in the prospective endoderm, and loss of srp activity causes transformation of the prospective endoderm into ectodermal foregut and hindgut, indicating that srp acts as a selector gene to specify the developmental fate of the endoderm. While srp is expressed in the endoderm only during early stages, it activates a subsequent GATA factor gene, dGATAe, and the latter continues to be expressed specifically in the endoderm throughout life. dGATAe activates various functional genes in the differentiated endodermal midgut. An analogous mode of regulation has been reported in Caenorhabditis elegans, in which a pair of GATA genes, end‐1/3, specifies endodermal fate, and a downstream pair of GATA genes, elt‐2/7, activates genes in the differentiated endoderm. Functional homology of GATA genes in nature is apparently extendable to vertebrates, because endodermal GATA genes of C. elegans and Drosophila induce endoderm development in Xenopus ectoderm. These findings strongly imply evolutionary conservation of the roles of GATA factors in the endoderm across the protostomes and the deuterostomes.
Effects of dyskinesias in Parkinson's disease on quality of life and health‐related costs: a prospective European study
Authors: Péchevis M. , Clarke C. E. , Vieregge P. , Khoshnood B. , Deschaseaux‐Voinet C. , Berdeaux G. , Ziegler M. ,   on behalf of the Trial Study Group
Published: November 2005

The treatment of Parkinson's disease (PD) with l‐DOPA leads to involuntary movements (dyskinesias). This 6‐month observational study in three European countries in PD patients with various degrees of motor complications examined the effects of dyskinesias on the quality of life (QoL) of patients and health care costs. Retrospective and prospective health economic data were collected, and QoL of patients was measured using the Short Form‐36 (SF‐36) and the PD Quality of Life (PDQL) Scale. Regression analysis was used to estimate the adjusted effects of dyskinesias on QoL and costs, whilst accounting for the potentially confounding effects of disease progression, motor fluctuations and country. Increasing dyskinesia scores on either the Unified PD Rating Scale or the Goetz Dyskinesia Rating Scale were associated with significant reductions in QoL scores on the SF‐36 and PDQL Scale. Increasing dyskinesia severity was also associated with increased depression scores on the Montgomery–Asberg Depression Rating Scale along with significant increases in health care costs. The effects of dyskinesia on QoL, depression and costs decreased but remained significant after adjustment for the confounding effects of disease progression and motor fluctuations. In conclusion, dyskinesias may adversely affect QoL and increase health care costs in patients with PD. Future studies should evaluate the potentially beneficial effects in terms of QoL and health care costs of strategies to delay the onset of, or the treatment of, dyskinesias.
Sex differences in carpal tunnel syndrome: comparison of surgical and non‐surgical populations
Authors: Mondelli M. , Aprile I. , Ballerini M. , Ginanneschi F. , Reale F. , Romano C. , Rossi S. , Padua L.
Published: November 2005

Carpal tunnel syndrome (CTS) patients are known to show gender‐related differences in severity. The main aim of this cross‐sectional study was to determine whether these differences between women and men may be related to age, education or body mass index (BMI) in two populations, one with idiopathic CTS not treated surgically and the other with idiopathic CTS treated by surgical decompression. A secondary aim was to check differences in surgical results between the genders in the surgical population. The non‐surgical population consisted of 172 subjects (126 women and 46 men, mean age 55.1 years) whose data were obtained at electrophysiological examination. The surgical population consisted of 219 patients (177 women and 42 men, mean age 55.1 years) whose data were obtained before surgery. Age, education, BMI, duration of symptoms, electrophysiological and clinical severity of CTS (with ordinal scales), and the self‐administered Boston Questionnaire (BQ) of symptoms and functional status of hands were considered. There were no differences in age or clinical and electrophysiological severity between women and men in either group, except for distal motor latency of the median nerve that was more delayed and duration of symptoms that was shorter in men than women in non‐surgical sample. Men had a higher BMI than women. Women had higher BQ scores in the surgical and non‐surgical samples. These differences remained when the results were analysed matching the men with an identical number of women of the same age, education and BMI. In the surgical population, the results of surgical decompression did not modify the gender‐related differences in severity. As in many other syndromes and diseases, for a given clinical severity, women with CTS were more sensitive than men in reporting their symptoms. Risk factors of CTS, such as age, education and BMI, were not responsible for these differences. The results of surgical decompression were similar in men and women.
Creutzfeldt–Jakob disease risk andPRNPcodon 129 polymorphism: necessity to revalue current data
Authors: Mitrová E. , Mayer V. , Jovankovičová V. , Slivarichová D. , Wsólová L.
Published: November 2005

The polymorphism at codon 129 (M129V) of the prion protein gene (PRNP) is a recognized genetic marker for susceptibility to Creutzfeldt–Jakob disease (CJD) in the Caucasians. The distribution of this polymorphism in healthy individuals provides an important starting point for the evaluation of CJD risk in the general population. Early studies of reference population cohorts demonstrated that methionine/valine heterozygosity was the most frequent genotype. These studies were performed in relatively small numbers of control subjects and do not correspond with the findings of more recent investigations. In this study, we present an analysis of the codon M129V distribution in 613 corneal donors, representing one of the largest control groups examined to date. Methionine homozygotes represented 48.1%, valine homozygotes 8.7% and methionine/valine heterozygotes 43.2%. While age‐related difference was not significant, differentiation according to the gender showed significant difference. The observed highest proportion of methionine homozygotes and statistically significant difference between genders as well as comparison with results obtained in other countries underline the need to re‐evaluate the generally used reference data on M129V, including consideration of the gender, age and geographical distribution.
Isolated pontine infarcts: etiopathogenic mechanisms
Authors: Erro M. E. , Gállego J. , Herrera M. , Bermejo B.
Published: November 2005

Although there are several clinico‐topographical studies of pontine infarcts, few include vascular studies. To clarify the etiopathogenic mechanisms of pontine infarcts we analyzed the vascular findings and their association with MRI lesions. The clinical features and vascular findings on transcranial Doppler (TCD) or MR angiography (MRA) of 67 patients with acute infarcts involving the pons were studied. Functional outcome was assessed by modified Rankin Scale (mRS) scores on admission and 2 months later. Two groups of isolated pontine infarcts were found on the basis of lesion location on MRI, according to the extent or not to the anterior surface of the pons: paramedian pontine infarcts (PPI, n = 36) and lacunar pontine infarcts (LPI, n = 31). Hypertension was the most common vascular risk factor and pure motor syndrome was the most frequent clinical profile in both groups. Basilar artery stenosis found on TCD or MRA was significantly more frequent amongst the PPI group (P < 0.05). On admission and 2 months later, the mRS scores of the PPI group were significantly worse (P < 0.0001) than those of the LPI group. Patients with PPI have a significantly higher frequency of basilar artery stenosis and they have a worse prognosis than patients with LPI.
A role of TNF‐αgene variant on juvenile ischemic stroke: a case–control study
Authors: Rubattu S. , Speranza R. , Ferrari M. , Evangelista A. , Beccia M. , Stanzione R. , Assenza G. E. , Volpe M. , Rasura M.
Published: November 2005

The role of genetic factors in the individual predisposition to develop ischemic stroke has been assessed by previous studies performed both in animal models and in humans. The main goal of the current investigation was to determine the possible contribution of genes encoding procoagulant and inflammatory factors on the occurrence of ischemic stroke in a cohort of young cases and corresponding controls. One hundred and fifteen cases of ischemic stroke were recruited for this study. A detailed clinical assessment, a definite etiologic diagnosis, as well as the presence/absence of known risk factors for ischemic stroke were obtained for each patient. As a control group 180 healthy, unrelated subjects were included. The whole population was screened for polymorphisms belonging to genes encoding FII, FV,α‐fibrinogen,β‐fibrinogen, GP IIb/IIIa, tumor necrosis factor (TNF)‐α, interleukin 1‐β. Hypertension was the most important risk factor for ischemic stroke in our cohort [OR = 6.9, confidence interval (CI) 2.9–16.7,P < 0.0001]. Among all genes tested, the TNF‐αgene variant exerted a significant, independent effect on individual predisposition to ischemic stroke occurrence (OR = 1.8, CI = 1.01–3.3,P < 0.05). Our findings, obtained in a cohort of young Italian patients, may support the existence of a direct contributory role of TNF‐α, a proinflammatory cytokine protein, in the susceptibility to brain damage.
EFNS task force on management of amyotrophic lateral sclerosis: guidelines for diagnosing and clinical care of patients and relatives
Authors: Andersen P. M. , Borasio G. D. , Dengler R. , Hardiman O. , Kollewe K. , Leigh P. N. , Pradat P.‐F. , Silani V. , Tomik B.
Published: November 2005

Despite being one of the most devastating diseases known, there is little evidence for diagnosing and managing patients with amyotrophic lateral sclerosis (ALS). Although specific therapy is lacking, correct early diagnosis and introduction of symptomatic and specific therapy can have a profound influence on the care and quality of life of the patient and may increase survival time. This document addresses the optimal clinical approach to ALS. The final literature search was performed in the spring of 2005. Consensus recommendations are given graded according to the EFNS guidance regulations. Where there was lack of evidence but consensus was clear we have stated our opinion as good practice points. People affected with possible ALS should be examined as soon as possible by an experienced neurologist. Early diagnosis should be pursued and a number of investigations should be performed with high priority. The patient should be informed of the diagnosis by a consultant with a good knowledge of the patient and the disease. Following diagnosis, the patient and relatives should receive regular support from a multidisciplinary care team. Medication with riluzole should be initiated as early as possible. PEG is associated with improved nutrition and should be inserted early. The operation is hazardous in patients with vital capacity <50%. Non‐invasive positive pressure ventilation improves survival and quality of life but is underused. Maintaining the patients ability to communicate is essential. During the entire course of the disease, every effort should be made to maintain patient autonomy. Advance directives for palliative end of life care are important and should be fully discussed early with the patient and relatives respecting the patients social and cultural background.