bluuebunny/crossref_metadata_2025 huggingface dataset:
Outcome of surgical concepts in haemophilic arthropathy of the hindfoot
Authors: Panotopoulos J. , Hanslik‐Schnabel B. , Wanivenhaus A. , Trieb K.
Published: August 2005

Summary.  The ankle is one of the most frequent joint affected by haemophilia, in the second decade of life it can be considered as the most common site for haemophilic arthropathy. The aim of this study is to evaluate the results of 15 surgical interventions of the hindfoot performed on 11 patients. Twenty‐seven of 70 male patients suffering from haemophilia were treated for haemophilic arthropathy of the hindfoot. We performed 15 operations on 11 patients with a mean age of 33.5 (range: 10–53) years. The surgical treatment consisted of 15 operations, 12 of which concerned the talocrural joint (six synovectomies, three radiosynoviorthesis, four arthrodeses, one achilles tendon lengthening) and one the talocalcaneonavicular joint (one triplearthrodesis). The arthrodeses of the talocrural joint were undertaken by screw, the triplearthrodesis by clamp fixation. The synovectomies were all late synovectomies and performed by open means. The mean follow‐up period was 32.0 (range: 12–84) months. The mean age at surgery was 29.6 (range: 8–51) years. No perioperative complications were registered when adequate replacement therapy was carried out. The consolidation of the arthrodeses was accomplished within 8–12 weeks. All synovectomies stopped or reduced significantly recurrent joint bleeding. With both procedures we achieved pain relief and walking ability improvement. The aim of synovectomy is to reduce bleeding episodes. If synovectomy can halt the progression of the haemophilic arthropathy is controversially discussed, especially when surgery was carried out in the presence of an established arthropathy. If synovectomy fails, the arthrodesis proves to be a good treatment option.
Prevalence of conditions associated with human immunodeficiency and hepatitis virus infections among persons with haemophilia, 2001–2003
Authors: Goedert J. J. ,   The Second Multicenter Hemophilia Cohort Study
Published: August 2005

Summary. Before the mid‐1980s, haemophilia often was unknowingly treated with contaminated plasma products, resulting in high rates of human immunodeficiency virus (HIV‐1), hepatitis C virus (HCV) and hepatitis B virus (HBV) infections. To estimate the impact of these infections, a new cohort was established. All HCV‐seropositive patients, age 13–88 years, at 52 comprehensive haemophilia treatment centres were eligible. Cross‐sectional data collected during April 2001 to January 2004 (median June 2002) were analysed. Plasma HIV‐1 and HCV RNA were quantified by polymerase chain reaction. Highly active antiretroviral therapy (HAART) was defined as use of at least three recommended medications. Among 2069 participants, 620 (30%) had HIV‐1. Of 1955 with known HBV status, 814 (42%) had resolved HBV and 90 (4.6%) were HBV carriers. Although 80% of the HIV‐1‐positive participants had ≥200 CD4+cells μL−1, only 59% were on HAART. HIV‐1 RNA was undetectable in 23% of those not taking antiretroviral medications. Most (72%) participants had received no anti‐HCV therapy. HCV RNA was detected less frequently (59%) among participants treated with standard interferon plus ribavirin (P = 0.0001) and more frequently among HIV‐1‐positive than HIV‐1‐negative participants (85% vs. 70%,P < 0.0001). HIV‐1‐positive participants were more likely to have pancytopenia and subclinical hepatic abnormalities, as well as persistent jaundice, hepatomegaly, splenomegaly and ascites. HAART recipients did not differ from HIV‐negative participants in the prevalence of ascites. The clinical abnormalities were more prevalent with older age but were not confounded by HBV status or self‐reported alcohol consumption. Eleven participants presented with or previously had hepatocellular carcinoma or non‐Hodgkin lymphoma. Although prospective analysis is needed, our data reveal the scale of hepatic and haematological disease that is likely to manifest in the adult haemophilic population during the coming years unless most of them are successfully treated for HIV‐1, HCV or both.
Ortner syndrome and haemophilia
Authors: Hermans C. , Manocha S. , McLaughlin J. E. , Lipman M. , Lee C. A.
Published: August 2005

Summary.  Compression and paralysis of the left recurrent laryngeal nerve by a dilated pulmonary artery is a rare complication of pulmonary hypertension. We here report the case of a patient with severe haemophilia A and HIV infection who presented with a persistent hoarseness of voice and a left vocal cord palsy caused by HIV‐associated pulmonary hypertension. This case suggests that HIV‐associated pulmonary hypertension should be suspected in any HIV patient presenting with unexplained left vocal cord palsy.
Microtensile adhesion of sealants to intact enamel
Authors: PERDIGÃO J. , FUNDINGSLAND J. W. , DUARTE S. , LOPES M.
Published: August 2005

Summary. Contamination of etched enamel with saliva has been shown to result in sealant failure. Hydrophilic adhesives improve retention of sealants when enamel is contaminated.

Objective. The objective of the present study was to characterize the adhesion of two sealants to unprepared enamel etched with phosphoric acid or conditioned with the all‐in‐one, self‐etch adhesive Adper Prompt L‐Pop.

Methods. The two proximal enamel surfaces of 16 sound molars were assigned to four conditioning regimens: (1) 35% phosphoric acid for 15 s; (2) Adper Prompt L‐Pop, one layer light‐cured prior to sealant placement; (3) Adper Prompt L‐Pop, two layers light‐cured prior to sealant placement; and (4) Adper Prompt L‐Pop, one layer co‐cured with sealant. One of two sealants, i.e. Clinpro or Delton DDS, was applied, light‐cured, followed by a composite build‐up to provide support for microtensile bond testing.

Results. The highest mean bond strengths were obtained when Adper Prompt L‐Pop was applied in two layers and light‐cured prior to the insertion of Clinpro Sealant. Co‐cure of Adper Prompt L‐Pop with either sealant resulted in bond strengths which were not significantly different from those of the phosphoric acid control. The use of Adper Prompt L‐Pop in one layer cured prior to sealant placement resulted in statistically lower bond strengths than any other application technique regardless of the sealant used. Clinpro Sealant resulted in statistically higher bond strengths than Delton DDS Sealant.

Conclusions. Application of one layer of Adper Prompt L‐Pop co‐cured with the sealant resulted in bond strengths similar to those obtained with phosphoric acid etching.
Factors associated with active white enamel lesions
Authors: FERREIRA M. Â. F. , MENDES N. S.
Published: August 2005

Summary. Objective. The aim of this study was to assess the factors associated with the presence of active white enamel lesions among public school students in the city of Natal, Brazil.

Methods. A convenience sample of 300 boys and girls aged between 7 and 12 years was selected among the pupils attending public schools in the city of Natal. Only those children presenting with opaque and rough‐surface white lesions in a region of biofilm accumulation on the vestibular surface of permanent upper incisors were included. The investigation took the form of a cross‐sectional study. A chart containing individual data was used, and a clinical examination was performed to determine the oral health status of the children, including caries (DMF‐s1, DMF‐s2, DMFdmf, dmf and total number of teeth with caries) and oral hygiene status (Gingival Bleeding Index and Visible Plaque Index). Data underwent descriptive analysis and analysis of variance, and chi‐square tests were used for the comparison of continuous and dichotomous variables between groups with one, two, or three or more white lesions.

Results. On average, each child presented with 2·3 teeth affected by white lesions, relatively high indices of dental caries and poor oral hygiene, with an 85% rate of localized plaque on the surfaces of teeth with lesions. The presence of visible plaque was statistically significant between the three groups, based on the number of lesions (P = 0·006), indicating a positive association between the number of lesions and the presence of biofilm.

Conclusion. There is a strong association between the presence of dental biofilm, high indices of caries and active white enamel lesions. Full professional effort is needed in order to motivate children to carry out oral hygiene sufficient for the adequate control of dental biofilm.
Witkop tooth and nail syndrome: a case report
Authors: DEVADAS S. , VARMA B. , MUNGARA J. , JOSEPH T. , SARASWATHI T. R.
Published: August 2005

Summary. Witkop tooth and nail syndrome is an autosomal dominant ectodermal dysplasia characterized by hypodontia and nail dysplasia. Mutations in MSX‐1 have been identified as being involved in the syndrome. Mandibular incisors, secondary molars and maxillary canines are the most frequently missing teeth. Tooth shape may vary, and conical and narrow crowns are common. Nail dysplasia affects finger‐ and toenails, and is often more severe in childhood. Nails may be spoon‐shaped, rigid, slow‐growing and easily broken. The clinical and radiographic features of a mother and child presenting with this rare condition are described.
An investigation of language used by children to describe discomfort expected and experienced during dental treatment
Authors: HARMAN K. , LINDSAY S. , ADEWAMI A. , SMITH P.
Published: August 2005

Summary.  Objectives. A study of dental pulp testing has shown that children's linguistic comprehension and chronological age independently influence their descriptions of pain. The present study sought first to demonstrate this for expectations and experience of routine dental treatment, and secondly, to determine whether the effect of age was the result of previous dental and medical experience.

Sample. Forty‐six children between 6 and 17 years of age attending two paediatric dental clinics for routine invasive procedures comprised the study sample.

Methods. To describe their expectations of forthcoming treatment, each child selected words from a published list, and gave ratings on scales describing the degree of severity as ‘sore’ or ‘tingly’. They also completed the Child Dental Anxiety Scale and the Spielberger State‐Trait Anxiety Scale for Children. After treatment, they described the treatment with the same list and scales, then completed the British Picture Vocabulary Scale and a dental–medical history questionnaire.

Results. The children, especially the most anxious ones, chose more words from the list for their expectations than for their experience of treatment, suggesting, as in previous studies, that they expected more discomfort than they experienced. Ratings of ‘sore’ and ‘tingly’ did not show this discrepancy. For both expectations and experience of treatment, the children with the largest vocabularies chose the fewest words, thus being more discriminating in their choices. However, vocabulary had no effect on ratings of ‘sore’ and ‘tingly’. There were no significant relationships among age, estimates of discomfort and medical–dental histories.

Conclusions. The results suggest that a list of adjectives provides the most discriminating measure of discomfort. They also show that it is necessary to take into account children's linguistic development to evaluate their estimates of pain so as not to entertain the belief of many clinicians that children exaggerate such reports.
Enamel hypoplasia of the primary dentition in a 4‐year‐old with intestinal lymphangiectasia
Authors: ARROW P.
Published: August 2005

Summary. Intestinal lymphangiectasia (IL) is a rare disorder, and its incidence and prevalence is unknown for either Australia or world‐wide. It is characterized by diarrhoea, mild steatorrhoea, oedema, enteric loss of protein (protein‐losing enteropathy) and abnormal dilated lymphatic channels in the small intestine. Whilst oedema and diarrhoea are the predominant clinical features, other observed features include hypoalbuminemia, hypogammaglobulinemia, trace metal deficiency, hypocalcemia and chylous pleural effusions. While medical presentation of the condition has been reported widely, few descriptions of oral findings have been published. A search of Medline found two reports of dental findings in the permanent dentition in patients with IL. To date, there have been no reports on dental findings in the primary dentition. The primary dentition of a 4‐year‐old boy with IL had teeth with enamel defects which reflected the timing of enamel development and the period in which the disease was active. The present report highlights the need for early involvement of the dental team in the dental management of children with IL.
The effect of an intermediate layer of flowable composite resin on microleakage in packable composite restorations
Authors: ZISKIND D. , ADELL I. , TEPEROVICH E. , PERETZ B.
Published: August 2005

Summary.  Objectives. The aim of the present study was to evaluate the effect of a thin layer of flowable composite on microleakage in Class II direct packable composite resin restorations on young permanent teeth in vitro.

Methods. Twenty sound human premolars and molars extracted for orthodontic reasons were selected for this study. The teeth were randomly assigned into two groups of 10 teeth each (groups A and B). Class II cavities were prepared as uniformly as possible in the mesial and distal aspects of each tooth. The gingival margin extended apically approximately 0·5 mm beyond the cemento‐enamel junction, in the dentin. Cavities in group A were restored with packable composite and Alert®/Flow‐it® flowable composite, while groups B cavities were restored with Pyramid®/Aeliteflo®. The control cavities in groups A1 and B1 were restored with only packable composite. The teeth were immersed in 2% methylene blue solution for 24 h to allow dye penetration into possible existing gaps between the tooth substance and the restorative material. All teeth were subjected to thermocycling.

Results. The dye penetration ranged between 6·6 and 7·2 mm. No significant difference was found between the control and the experimental groups.

Conclusion. The use of flowable composite resin as intermediate material does not reduce microleakage.
The biological sciences in nursing: a developing country perspective
Authors: Kyriacos Una , Jordan Sue , Van Den Heever Jean
Published: August 2005

Aim.  This paper reports a study to inform curriculum development by exploring the contribution of bioscience education programmes to nurses’ clinical practice, their understanding of the rationale for practice, and their perceptions of their continuing professional development needs.

Background.  The future of the health services worldwide depends on nurse education programmes equipping practitioners to deliver safe and effective patient care. In the developed world, the structure and indicative content of nursing curricula have been debated extensively. However, despite the rapid expansion in nursing roles brought about by social change, there is little information on the educational needs of nurses in developing countries.

Methods.  This study was undertaken in government teaching hospitals in Cape Town, South Africa in 2003. A purposive sample of 54 nurses from a range of clinical settings completed questionnaires and described critical incidents where bioscience knowledge had directed practice. Questionnaires were analysed descriptively, in the main. Analysis of critical incident reports was based on Akinsanya's bionursing model.

Findings.  Most nurses felt that their understanding of the biological, but not the physical sciences, was adequate or better: all felt confident with their knowledge of anatomy, compared with 57·4% (31/54) for microbiology. Respondents attributed the successes and failures of their education programmes to their teachers’ delivery of content, ability to relate to practice and management of the process of learning. The biological, but not the physical, sciences were universally (96–100%) regarded as relevant to nursing. However, the critical incidents and nurses’ own reports indicated a need for further education in pharmacology (40/54, 74·1%) and microbiology (29/54, 53·7%).

Conclusion.  To meet the needs of nurses in developing countries, and empower them to meet the increasingly complex demands of their expanding roles, nurse educators need to consider increasing the curriculum content in certain key areas, including pharmacology and microbiology.
Parenting experiences during cancer
Authors: Helseth Sølvi , Ulfsæt Nina
Published: August 2005

Aim.  This paper reports a study to increase our understanding of how cancer affects childcare through assessing the parenting experiences of cancer patients and their spouses with young children.

Background.  A parent's cancer brings insecurity into the life of a child. It affects their well‐being and increases their needs for comfort and care. However, little research has been conducted to understand how a parent's illness affects parenting and the care of the child. The study was carried out in 2001–2002.

Methods.  An explorative design was chosen and data were collected through in‐depth interviews with a convenience sample of 18 parents of 23 children (aged 0–18 years) in 10 families.

Findings.  Parents described living in a state of emergency. Cancer was consuming their energy, physically and emotionally. In spite of their difficulties, they were striving to be good parents. Positive aspects of illness reported were a shift of priorities and change of values that often brought family members closer together. The parents would face the challenges of illness by making the best of it, putting the needs of the children in focus and trying to maintain normal family life. The overall aim of parenting would be to protect the children and make the illness situation as secure and normal as possible for them.

Conclusion.  Cancer is a challenge and often necessitates changes in parenting roles, responsibilities and goals. In the future, nurses need to approach parents with young children more directly about these extra challenges, and offer them further assistance in dealing with them.
Regulation of Expression of Mammalian Gonadotrophin‐Releasing Hormone Receptor Genes
Authors: Hapgood J. P. , Sadie H. , Van Biljon W. , Ronacher K.
Published: August 2005

Gonadotrophin‐releasing hormone (GnRH), acting via its cognate GnRH receptor (GnRHR), is the primary regulator of mammalian reproductive function, and hence GnRH analogues are extensively used in the treatment of hormone‐dependent diseases, as well as for assisted reproductive techniques. In addition to its established endocrine role in gonadotrophin regulation in the pituitary, evidence is rapidly accumulating to support the expression and functional roles for two forms of GnRHR (GnRHR I and GnRHR II) in multiple and diverse extra‐pituitary mammalian tissues and cells. These findings, together with findings indicating that mutations of the GnRHR are linked to the disease hypogonadotrophic hypogonadism and that GnRHRs play a direct role in neuronal migration and reproductive cancers, have presented new therapeutic targets and intensified research into the structure, function and mechanisms of regulation of expression of GnRHR genes. The present review focuses on the current knowledge on tissue‐specific and hormonal regulation of transcription of mammalian GnRH receptor genes. Emerging insights, such as the discovery of diverse regulatory mechanisms in pituitary and extra‐pituitary cell types, nonclassical mechanisms of steroid regulation, the use of composite elements for cell‐specific expression, the increasing profile of hormones involved in regulation, the complexity of kinase pathways that target the GnRHR I gene, as well as species‐differences, are highlighted. Although further research is necessary to understand the mechanisms of regulation of expression of GnRHR I and GnRHR II genes, the GnRHR is emerging as a potential target gene for facilitating cross‐talk between neuroendocrine, immune and stress‐response systems in multiple tissues via autocrine, paracrine and endocrine signalling.
Effects of Calmodulin on Aromatase Activity in the Preoptic Area
Authors: Balthazart J. , Baillien M. , Charlier T. D. , Ball G. F.
Published: August 2005

Oestrogens derived from the neural aromatisation of testosterone play a key role in the activation of male sexual behaviour in many vertebrates. Besides their slow action on gene transcription mediated by the binding to nuclear receptors, oestrogens have now been recognised to have more rapid membrane‐based effects on brain function. Rapid changes in aromatase activity, and hence in local oestrogen concentrations, could thus rapidly modulate behavioural responses. We previously demonstrated that calcium‐dependent kinases are able to down‐regulate aromatase activity after incubations of 10–15 min in phosphorylating conditions. In the present study, in quail hypothalamic homogenates, we show that Ca2+ or calmodulin alone can very rapidly change aromatase activity. Preincubation with 1 mM EGTA or with a monoclonal antibody raised against calmodulin immediately increased aromatase activity. The presence of calmodulin on aromatase purified by immunoprecipitation and electrophoresis was previously identified by western blot and two consensus binding sites for Ca2+‐calmodulin are identified here on the deduced amino acid sequence of the quail brain aromatase. The rapid control of brain aromatase activity thus appears to include two mechanisms: (i) an immediate regulatory process that involves the Ca2+‐calmodulin binding site and (ii) a somewhat slower phosphorylation by several protein kinases (PKC, PKA but also possibly Ca2+‐calmodulin kinases) of the aromatase molecule.
Optimal life stage for radiation sterilization of Anopheles males and their fitness for release
Authors: Andreasen M. H. , Curtis C. F.
Published: August 2005

Abstract.  Mating by male Anopheles mosquitoes (Diptera: Culicidae) was evaluated in the laboratory to assess fitness effects of radio‐sterilization applied during different life stages of the malaria vectors An. stephensi Liston and An. gambiae Giles sensu stricto. After reproductive sterilization by gamma‐irradiation (120 Gy), equal proportions of sterile and fertile (unirradiated) male adults were released into cages with virgin females and allowed to compete for matings. Radio‐sterilization was applied when the males were pupae aged 0–7 h or 24–32 h, or adults aged  <24 h or 24–55 h. After being radio‐sterilized in the adult stage, males of both species competed effectively with unirradiated males, whereas those sterilized in the pupal stage obtained significantly fewer matings than unirradiated males from the same cohort. There was no evidence of females obtaining multiple inseminations. These findings emphasize the need to radio‐sterilize males as adults in order to minimize the fitness cost. Such males may be intended for sterile insect technique population suppression or for trial releases of transgenic anophelines.
Influence of weather conditions on fly abundance and its implications for transmission of rabbit haemorrhagic disease virus in the North Island of New Zealand
Authors: Henning J. , Schnitzler F.‐R. , Pfeiffer D. U. , Davies P.
Published: August 2005

Abstract.  Blowflies (Diptera: Calliphoridae) and flesh flies (Diptera: Sarcophagidae) are potential vectors of rabbit haemorrhagic disease virus (RHDV) in New Zealand. The associations between habitat and weather factors on the abundance of these flies were investigated. Between October 1999 and June 2001, flies were trapped on open pasture and in dense vegetation patches on farmland in the Himatangi area of the North Island. Five calliphorid species were trapped commonly at scrub edges and the most abundant sarcophagid, Oxysarcodexia varia Walker, was trapped mainly on open pasture. An abundance peak of O. varia was probably associated with the occurrence of a rabbit haemorrhagic disease (RHD) outbreak in the study area. Overall abundance of flies varied according to habitat and species, and species numbers differed between seasons and years. The all‐day minimum temperature 3 weeks before trapping was a significant variable in all models of fly abundance, whereas average rainfall did not affect fly abundance. The all‐day temperature range was significant only for O. varia. The influence of other climatic factors varied between fly species. Climate dependent variations in fly abundance may contribute to the risk of transmission of RHD, which occurred intermittently on the site during the study period.
Analysis of a complex vertical copulatory‐courtship display in the yellow fever vector Sabethes chloropterus
Authors: Zsemlye J. L. , Hancock R. G. , Foster W. A.
Published: August 2005

Abstract.  Sabethes chloropterus (Von Humboldt) (Diptera: Culicidae), an arboreal mosquito vector of the yellow fever virus, perches on vertical surfaces, where airborne males patrol for potential mates and mating occurs. Laboratory analysis of 26 virgin mating pairs partly confirms and greatly extends an earlier description suggesting that males perform a courtship ritual. A male approaches a female by hovering behind her, moving toward her from one side, reaching toward her and occasionally touching her with his closest midleg, and eventually seizing her wing with that midleg and inverting beneath her, forelegs against the substrate. Immediately after male alignment with the female, the pair enters a superficial genital‐coupling phase, in which the male's extended gonostyli are linked to the female, and he proceeds sequentially through four stages of midleg oscillations (MLOs): Alternate I, Synchronous I, Double‐flex, and Synchronous II. Following one or more genital thrusts, the pair shifts to a full‐copulation phase, which lasts only up to 6 s, during which the genitalia are clasped and insemination occurs. The male raises his midlegs and hindlegs in succession, then performs Alternate II MLO until the female kicks him and he is released. Nineteen (73%) of the 26 pairs successfully completed the entire sequence, including genital shift and full copulation, taking an average of 3.7 min. Features of the display that might determine success were not evident. Reversions in the chain of events occurred, but linear progression of stages and phases was characteristic of nearly all matings. The male's approach, however, lacked stereotypic form and probably is not part of the courtship.
Distribution of Ixodes ricinus in the British Isles: investigation of historical records
Authors: Pietzsch M. E. , Medlock J. M. , Jones L. , Avenell D. , Abbott J. , Harding P. , Leach S.
Published: August 2005

Abstract.  Ixodes ricinus Linnaeus (Acari: Ixodidae) is the most abundant and widely distributed tick in the British Isles, and is a vector for a number of bacterial, viral and protozoal pathogens of both medical and veterinary importance. This report provides an update to the historical distribution data of I. ricinus, published by the Biological Records Centre (BRC), Monks Wood in The Provisional Atlas of the Ticks (Ixodidae) of the British Isles by K. P. Martyn (1988), and is supplemented with additional BRC records since 1988, additional data from published scientific literature and unpublished field studies, and enhanced with spatial and temporal information on tick stages collected and their host associations. Records have been mapped at 10 km resolution and enhanced to 5 km, 1 km and 0.1 km. Differentiation between records representing one‐off collections from those representing populations of I. ricinus has been achieved through the classification of the records into either reported or established populations. Detailed seasonality and host associations of records are investigated, highlighting the value in obtaining additional detailed contemporary data to aid risk assessments and research within this field.
Species delimitation in native South American fire ants
Authors: ROSS KENNETH G. , SHOEMAKER D. DEWAYNE
Published: August 2005

The taxonomy of fire ants has been plagued by difficulties in recognizing species on the basis of morphological characters. We surveyed allozyme markers and sequences of the mtDNACOIgene in several closely related nominal species from two areas of sympatry in the native ranges to learn whether the morphology‐based delimitation of these species is supported by genetic data. We found thatSolenopsis invictaandSolenopsis richteri, pest species whose distinctiveness has been debated, appear to be fully reproductively isolated at both study sites. This isolation contrasts with the extensive hybridization occurring between them in the USA, where both have been introduced. We also found strong genetic differentiation consistent with barriers to gene flow betweenSolenopsis quinquecuspisand the other two species. However, several lines of evidence suggest that nuclear and mitochondrial genes ofS. invictaandS. richteriare introgressing intoS. quinquecuspis. The latter apparently is a recently derived member of the clade that includes all three species, suggesting that there has been insufficient time for its full development of intrinsic isolating mechanisms. Finally, our discovery of genetically distinct populations within bothS. invictaandS. richterisuggests the presence of previously unrecognized (cryptic) species. Their existence, together with the difficulties in developing diagnostic morphological characters for described species, imply that the group is actively radiating species and that morphological divergence generally does not keep pace with the development of reproductive isolation and neutral genetic divergence in this process.
Chloroplast and microsatellite DNA diversities reveal the introduction history of Brazilian peppertree (Schinus terebinthifolius) in Florida
Authors: WILLIAMS DEAN A. , OVERHOLT WILLIAM A. , CUDA JAMES P. , HUGHES COLIN R.
Published: August 2005

Brazilian peppertree (Schinus terebinthifolius) is a woody perennial that has invaded much of Florida. This native of northeastern Argentina, Paraguay, and Brazil was brought as an ornamental to both the west and east coasts of Florida at the end of the 19th century. It was recorded as an invader of natural areas in the 1950s, and has since extended its range to cover over 280 000 ha. Our goals were to understand the history of this invasion, as one step toward understanding why this exotic was so successful, and ultimately to improve development of biological control agents. We sampled plants from the native and exotic ranges, particularly Florida, and genotyped these individuals at nuclear and chloroplast loci. Nuclear microsatellite and cpDNA loci reveal strong genetic population structure consistent with limited dispersal in the introduced and native ranges. Bayesian clustering of microsatellite data separates the east and west coast plants in Florida into distinct populations. The two chloroplast haplotypes found in Florida are also concordant with this separation: one predominates on the east coast, the other on the west coast. Analysis of samples collected in South America shows that haplotypes as distinct as the two in Florida are unlikely to have come from a single source population. We conclude that the genetic evidence supports two introductions of Brazilian peppertree into Florida and extensive hybridization between them. The west coast genotype likely came from coastal Brazil at about 27° south, whereas the east coast genotype probably originated from another, as yet unidentified site. As a result of hybridization, the Florida population does not exhibit low genetic variation compared to populations in the native range, possibly increasing its ability to adapt to novel environments. Hybridization also has important consequences for the selection of biocontrol agents since it will not be possible to identify closely co‐adapted natural enemies in the native range, necessitating more extensive host testing.
Challenges for identifying functionally important genetic variation: the promise of combining complementary research strategies
Authors: VASEMÄGI A. , PRIMMER C. R.
Published: August 2005

Strategies for the identification of functional genetic variation underlying phenotypic traits of ecological and evolutionary importance have received considerable attention in the literature recently. This paper aims to bring together and compare the relative strengths and limitations of various potentially useful research strategies for dissecting functionally important genetic variation in a wide range of organisms. We briefly explore the relative strengths and limitations of traditional and emerging approaches and evaluate their potential use in free‐living populations. While it is likely that much of the progress in functional genetic analyses will rely on progress in traditional model species, it is clear that with prudent choices of methods and appropriate sampling designs, much headway can be also made in a diverse range of species. We suggest that combining research approaches targeting different functional and biological levels can potentially increase understanding the genetic basis of ecological and evolutionary processes both in model and non‐model organisms.
Carbohydrate engineering of the recognition motifs in streptococcal co‐aggregation receptor polysaccharides
Authors: Yoshida Yasuo , Ganguly Soumya , Bush C. Allen , Cisar John O.
Published: August 2005

The cell wall polysaccharides of certain oral streptococci function as receptors for the lectin‐like surface adhesins on other members of the oral biofilm community. Recognition of these receptor polysaccharides (RPS) depends on the presence of a host‐like motif, either GalNAcβ1‐3Gal (Gn) or Galβ1‐3GalNAc (G), within the oligosaccharide repeating units of different RPS structural types. Type 2Gn RPS of Streptococcus gordonii 38 and type 2G RPS of Streptococcus oralis J22 are composed of heptasaccharide repeats that are identical except for their host‐like motifs. In the current investigation, the genes for the glycosyltransferases that synthesize these motifs were identified by high‐resolution nuclear magnetic resonance (NMR) analysis of genetically altered polysaccharides. RPS production was switched from type 2Gn to 2G by replacing wefC and wefD in the type 2Gn gene cluster of S. gordonii 38 with wefF and wefG from the type 2G cluster of S. oralis J22. Disruption of either wefC or wefF abolished cell surface RPS production. In contrast, disruption of wefD in the type 2Gn cluster or wefG in the type 2G cluster eliminated β‐GalNAc from the Gn motif or β‐Gal from the G motif, resulting in mutant polysaccharides with hexa‐ rather than heptasaccharide subunits. The mutant polysaccharides reacted like wild‐type RPS with rabbit antibodies against type 2Gn or 2G RPS but were inactive as co‐aggregation receptors. Additional mutant polysaccharides with GalNAcβ1‐3GalNAc or Galβ1‐3Gal recognition motifs were engineered by replacing wefC in the type 2Gn cluster with wefF or wefF in the type 2G cluster with wefC respectively. The reactions of these genetically modified polysaccharides as antigens and receptors provide further insight into the structural basis of RPS function.
Protein phosphatases in MAPK signalling: we keep learning from yeast
Authors: Martín Humberto , Flández Marta , Nombela César , Molina María
Published: August 2005

Because of their key role in cell signalling, a rigorous regulation of mitogen‐activated protein kinases (MAPKs) is essential in eukaryotic physiology. Whereas the use of binding motifs and scaffold proteins guarantees the selective activation of a specific MAPK pathway, activating kinases and downregulating phosphatases control the appropriate intensity and timing of MAPK activation. Tyrosine, serine/threonine and dual‐specificity phosphatases co‐ordinately dephosphorylate and thereby inactivate MAPKs. In budding yeast, enzymes that belong to these three types of phosphatases have been shown to counteract the MAPKs that govern the cellular response to varied extracellular stimuli. Studies carried out with these yeast phosphatases have expanded our knowledge of essential key aspects of the biology of these negative regulators, such as their function, the mechanisms that operate in their modulation by MAPK pathways and their binding to MAPK substrates. Furthermore, yeast MAPK phosphatases have been shown to play additional and essential roles in MAPK‐mediated signalling, controlling MAPK localization or cross‐talk among pathways. This review stresses the importance of these negative regulators in eukaryotic signalling by discussing the recent developments and perspectives in the study of yeast MAPK phosphatases.
The Aspergillus niger MADS‐box transcription factor RlmA is required for cell wall reinforcement in response to cell wall stress
Authors: Damveld Robbert A. , Arentshorst Mark , Franken Angelique , VanKuyk Patricia A. , Klis Frans M. , Van Den Hondel Cees A. M. J. J. , Ram Arthur F. J.
Published: August 2005

In Aspergillus niger, the genes coding for glutamine:fructose‐6‐phosphate amidotransferase (gfaA) and α‐1,3‐glucan synthase (agsA) are induced in response to cell wall stress. In silico analysis of the promoter region of the two genes revealed the presence of putative DNA binding sites for transcription factors involved in stress responses, including sites identical to the Saccharomyces cerevisiae Rlm1p and Msn2p/Msn4p transcription factors. Promoter analysis indicated that the induction of the agsA gene in response to cell wall stress is fully dependent on a putative Rlm1p binding site in its promoter region. Database searches revealed the presence of S. cerevisiae Rlm1p homologues in most filamentous fungi examined, including A. niger. Deletion of the RLM1 homologue, named rlmA in A. niger, completely eliminated the induction of agsA and resulted in a twofold reduced induction of gfaA during Calcofluor White‐induced cell wall stress. The rise in cell wall chitin in the presence of Calcofluor White was also affected in the rlmA deletion strain. In addition, the deletion strain was more sensitive towards cell wall stress agents. Our results indicate that A. niger responds to cell wall stress by transcriptional activation of cell wall reinforcing genes including agsA and gfaA through an Rlm1p‐like transcription factor. We propose that such a cell wall salvage mechanism is wide spread in filamentous fungi.
Effects of long‐term treatment with oxytocin in chronic constipation; a double blind, placebo‐controlled pilot trial
Authors: Ohlsson B. , Truedsson M. , Bengtsson M. , Torstenson R. , Sjölund K. , Björnsson E. S. , Simrèn M.
Published: August 2005

Abstract  Background:  Oxytocin and its receptor have been found throughout the gastrointestinal (GI) tract, where it affects gut function. Clinically, we have noticed an improvement of bowel habits during lactation in constipated women. The aim of this study was to examine whether oxytocin has an effect on bowel symptoms and psychological well being in women with refractory constipation.

Methods:  Fifty‐nine women with refractory constipation were included in a double blind, multicentre study. After a 2‐week run‐in period, they were randomly allocated to nasal inhalation of either placebo or oxytocin treatment twice daily for 13 weeks, followed by a 2 weeks, posttreatment period. The patients completed a questionnaire every day concerning bowel habits, abdominal pain and discomfort, and Gastrointestinal Symptoms Rating Scale (GSRS) and Psychological General Well‐being (PGWB) twice during the study; namely, during the baseline period and at the end of the treatment period.

Results:  Both oxytocin and placebo led to improvement of the constipation according to the GSRS and led to improvement in the sensation of incomplete evacuation and anorectal obstruction, without significant differences between the groups. Abdominal pain and discomfort responded weakly to oxytocin, with no effect of the placebo. In a subgroup of patients with IBS and concomitant depression, a weak improvement in depressed mood was observed after oxytocin administartion.

Conclusion:  Nasal administration of oxytocin had no significant advantage over placebo concerning an effect on constipation. However, it seems to have a positive effect on abdominal pain and discomfort and depressed mood. These findings should be further explored.
Quantitative trait loci controlling aluminium tolerance in two accessions of Arabidopsis thaliana (Landsberg erecta and Cape Verde Islands)
Authors: KOBAYASHI YURIKO , FURUTA YACHIYO , OHNO TAKASHI , HARA TETSUO , KOYAMA HIROYUKI
Published: August 2005

Quantitative trait loci (QTL) analysis of aluminium (Al) tolerance was performed using Ler/Cvi recombinant inbred (RI) lines of Arabidopsis thaliana. Relative root length (RRL) (root length with 4 µm Al/root length with no Al at pH 5.0) on day 5 was used as the Al tolerance index for QTL analysis. Al tolerance judged by RRL was well correlated to tolerance judged by other indexes, including accumulation of callose, reactive oxygen species in the root apex and growth performance on acid soil containing a large amount of exchangeable Al. Using data sets with an hb2 of 0.91, two QTLs were detected at the top of chromosome 1 and bottom of chromosome 3. These QTLs explained 40 and 16% of the phenotypic variation of Al tolerance, respectively, and the positive effect of the Cvi allele. The QTL on chromosome 1 overlapped with a major QTL in another recombinant inbred population, and is possibly related to malate excretion. A complete pair‐wise search revealed 11 sets of epistatic interacting loci pairs, which accounted for the transgressive segregation among the RI population. Several epistatic interactions shared the same chromosomal region, indicating the possible involvement of regulatory proteins in Al tolerance in Arabidopsis.
A new precipitation technique provides evidence for the permeability of Casparian bands to ions in young roots of corn (Zea mays L.) and rice (Oryza sativa L.)
Authors: RANATHUNGE KOSALA , STEUDLE ERNST , LAFITTE RENEE
Published: August 2005

Using an insoluble inorganic salt precipitation technique, the permeability of cell walls and especially of endodermal Casparian bands (CBs) for ions was tested in young roots of corn (Zea mays) and rice (Oryza sativa). The test was based on suction of either 100 µm CuSO4 or 200 µm K4[Fe(CN)6] into the root from its medium using a pump (excised roots) or transpirational stream (intact seedlings), and subsequent perfusion of xylem of those root segments with the opposite salt component, which resulted in precipitation of insoluble brown crystals of copper ferrocyanide. Under suction, Cu2+ could cross the endodermis apoplastically in both plant species (although at low rates) developing brown salt precipitates in cell walls of early metaxylem and in the region between CBs and functioning metaxylem vessels. Hence, at least Cu2+ did cross the endodermis dragged along with the water. The results suggested that CBs were not perfect barriers to apoplastic ion fluxes. In contrast, ferrocyanide ions failed to cross the mature endodermis of both corn and rice at detectable amounts. The concentration limit of apoplastic copper was 0.8 µm at a perfusion with 200 µm K4[Fe(CN)6]. Asymmetric development of precipitates suggested that the cation, Cu2+, moved faster than the anion, [Fe(CN)6]4–, through cell walls including CBs. Using Chara cell wall preparations (‘ghosts’) as a model system, it was observed that, different from Cu2+, ferrocyanide ions remained inside wall‐tubes suggesting a substantially lower permeability of the latter which agreed with the finding of an asymmetric development of precipitates. In both corn and rice roots, there was a significant apoplastic flux of ions in regions where laterals penetrated the endodermis. Overall, the results show that the permeability of CBs to ions is not zero. CBs do not represent a perfect barrier for ions, as is usually thought. The permeability of CBs may vary depending on growth conditions which are known to affect the intensity of formation of bands.
Seasonal shifts in dormancy status, carbohydrate metabolism, and related gene expression in crown buds of leafy spurge
Authors: ANDERSON JAMES V. , GESCH RUSS W. , JIA YING , CHAO WUN S. , HORVATH DAVID P.
Published: August 2005

Crown buds of field‐grown leafy spurge (Euphorbia esula L.) were examined to determine relationships between carbohydrate metabolism and gene expression throughout para‐, endo‐, and eco‐dormancy during the transition from summer, autumn, and winter, respectively. The data indicates that endo‐dormancy plays a role in preventing new shoot growth during the transition from autumn to winter. Cold temperature was involved in breaking endo‐dormancy, inducing flowering competence, and inhibiting shoot growth. An inverse relationship developed between starch and soluble sugar (mainly sucrose) content in buds during the shift from para‐ to endo‐dormancy, which continued through eco‐dormancy. Unlike starch content, soluble sugars were lowest in crown buds during para‐dormancy but increased over two‐ to three‐fold during the transition to endo‐dormancy. Several genes (AGPase, HK, SPS, SuSy, and UGPase) coding for proteins involved in sugar metabolism were differentially regulated in conjunction with well‐defined phases of dormancy in crown buds. Marker genes for S‐phase progression, cell wall biochemistry, or responsive to auxin were also differentially regulated during transition from para‐, endo‐, and eco‐dormancy. The results were used to develop a model showing potential signalling pathways involved in regulating seasonal dormancy status in leafy spurge crown buds.
Low night temperature and inhibition of gibberellin biosynthesis override phytochrome action and induce bud set and cold acclimation, but not dormancy in PHYA overexpressors and wild‐type of hybrid aspen
Authors: MØLMANN JØRGEN A. , ASANTE DANIEL K.A. , JENSEN JOHN B. , KRANE MARIA N. , ERNSTSEN ARILD , JUNTTILA OLAVI , OLSEN JORUNN E.
Published: August 2005

Juvenile trees of temperate and boreal regions cease growth and set buds in autumn in response to short day‐lengths (SD) detected by phytochrome. Growth cessation and bud set are prerequisites for the development of winter dormancy and full cold hardiness. In this study we show that the SD‐requirement for bud set and cold hardening can be overcome in hybrid aspen (Populus tremula L. × tremuloides Michx.) by low night temperature and inhibition of gibberellin (GA) biosynthesis. Bud set and increased cold hardiness were observed under normally non‐inductive long day‐length (LD) in wild‐type plants, when exposed to low night temperature and paclobutrazol. In addition, the effect of PHYA overexpression could be overcome in transgenic plants, producing bud set and cold acclimation by treatment with: SD, low night temperature and paclobutrazol. After cold acclimation, the degree of bud dormancy was lower for wild‐type plants prior treated with LD and transgenic plants (overexpressing PHYA), than SD‐treated, wild‐type plants. Thus, low night temperature in combination with reduced GA content induced bud set and promoted cold hardiness under normally non‐inductive photoperiods in hybrid aspen, but was unable to affect development of dormancy. This might suggest separate signalling pathways from phytochrome regulating the induction of cold/cold hardiness and bud dormancy in hybrid aspen or alternatively, there might be one pathway that fails to complete its action in the transgenic and paclobutrazol treated plants.