bluuebunny/crossref_metadata_2025 huggingface dataset:
THE IMPACT OF CHILDHOOD SEXUAL ABUSE ON WOMEN'S Healthcare
Authors: Myskow L.
Published: August 2006

Prevalence studies show that between 15 and 30% of women have been sexually abused by a man by the age of 16. Child abuse survivors rarely spontaneously reveal this history to a doctor yet they are more likely than non‐abused patients to suffer multi‐system medical complaints and to indulge in high‐risk behaviours. This of course may make them more likely to appear in gynaecology or colposcopy clinics. It seems sensible that gynaecologists should be well informed about CSA and in particular the impact it may have on their patients so that they can offer the required sensitive treatment in an appropriate environment for these women in particular. Just as with rape the sexual component of child sexual abuse is of secondary importance to power over and manipulation of children, therefore psychological damage to children is much greater if the abuser is a parent or parent figure. Incest is most commonly between father or stepfather and daughter, with stepfathers being the worst offenders. The peculiar difficulties that follow sexual abuse of a child by a family member and which place the child in a seemingly impossible position in the family have been well‐described by Summit (1983). He uses the term CSA accommodation syndrome to describe a reaction, which allows for the immediate survival of the child within the family.

There are 5 components to this syndrome:‐

(1) Secrecy

(2) Helplessness

(3) Entrapment and Accommodation

(4) Delayed, Conflicted and Unconvincing disclosure

(5) Retraction

Unfortunately these children develop multiple psychological and emotional disorders in the process e.g. depression, high anxiety and panic attacks, obsessional concerns, eating disorders and abuse of self. They may also develop physical manifestations of emotional pain such as pseudo‐seizures or chronic pelvic pain. Not surprisingly, sexual problems are also common e.g. low sex drive or vaginismus. Despite the fact that abuse of children is very variable in severity, the treatment of abused women follows a recognised process which is similar in each case. Disclosure – therapy starts from this moment so it is important that it is handled well. She is encouraged to talk about the abuse as she remembers it and it is important that her therapist lets her know that her story is believed. Responsibility for the abuse is addressed. Almost without exception, victims of abuse feel responsible in some way for what happened so again her therapist must point out where the blame really lies i.e. with the abuser. Current family relationships have to be reviewed as she may still in fact be living with the abuser and part of the healing process may involve his confrontation. Finally moving from victim to survivor the woman addresses the damage that has been done. Many women attending colposcopy or gynaecology clinics will have suffered sexual abuse. They may find the experience traumatising and will be greatly helped to cope if the environment in which they are treated is sensitive and caring.
A MASTER CLASS IN UNDERSTANDING VARIATIONS IN HEALTHCARE
Authors: Mohammed M.
Published: August 2006

That there is wide‐spread variation in healthcare outcomes cannot be denied. The question is what does the variation mean and what can we do about it? Using a series of well‐known case‐studies, which include data from the Bristol and Shipman Inquiries, fundamental limitations of traditional methods of understanding variation will be highlighted. These methods, which include comparison with standards, league tables and statistical testing, have flaws and they offer little or no guidance on how to re‐act to the variation. Fortunately, there is a theory of variation that overcomes these limitations and provides useful guidance on re‐acting to variation, which was developed by Walter Shewhart in the 1920s in an industrial setting. Shewhart's theory of variation found widespread application and won him the accolade ‘Father of modern quality control’. His work is central to philosophies of continual improvement. Application of Shewhart's theory of variation, also known as Statistical Process Control (SPC), to case‐studies from healthcare will be demonstrated, whilst highlighting the implications and challenges for performance management/monitoring and continual improvement in the healthcare.

References:  1. M A Mohammed, KK Cheng, A Rouse, T Marshall. “Bristol, Shipman and clinical governance: Shewhart's forgotten lessons” The Lancet 2001; 357: 463–7.

2. P Adab, A Rouse, M A Mohammed, T Marshall. “Performance league tables: the NHS deserves better” British Medical Journal 2002; 324: 95–98
Creation of artificial upwelling areas for brown trout, Salmo trutta, spawning in still water bodies
Authors: BRABRAND Å. , HANSEN B. R. , KOESTLER A. G.
Published: August 2006

Abstract  Brown trout, Salmo trutta L., spawning sites were constructed by creating areas of artificial upwelling water, 252 ± 37 mL m−2 min−1 (95% CL), through appropriately sized spawning gravel substrate in 3 m2 vessels buried in the bottom of a 150‐m2 pond. Natural spawning occurred in the vessels during autumn 2001–2004, with hatching and alevin swim up the following spring. In areas of upwelling, egg survival was 85–95%, while no live eggs were observed in areas without upwelling. In areas with upwelling, the maximum density of live eggs at the eyed stage was 570–1510 eggs m−2. In spring 2004 and 2005, the density of alevins was estimated at 322 (±187) m−2 and 567 (±217) m−2, respectively, in areas with upwelling water, compared with 35.2 ± 25.4 m−2 in areas without upwelling water in 2004.
Interlocked use of inland fish resources: a new management strategy under private property rights
Authors: SIPPONEN M. , MUJE K. , MARJOMÄKI T. J. , VALKEAJÄRVI P. , KARJALAINEN J.
Published: August 2006

Abstract  Interlocked use of multiple inland vendace, Coregonus albula (L.), stocks is a relatively new strategy to exploit asynchronous fluctuations in abundance of natural fish stocks between waterbodies. It combines vendace stocks from different lakes or parts of lakes into one interlocked stock to be managed across waterbody ownership boundaries. Management of interlocked stocks can be regarded as one form of portfolio management. Exploitation of interlocked stocks should reduce the interannual variation in yield, and thus ensuring fishers more constant income and the market more constant material flow. The strategy requires fishers to increase their mobility, to benefit from asynchronous fluctuations in abundance of vendace stocks between exploitable waters. A postal inquire addressed to Finnish commercial inland fishers examined whether existing property rights institutions’ and fishers’ harvesting policies were appropriate to establish interlocked use of multiple vendace stocks. Almost half of fishers had, to some extent, reaped benefit from a fishing strategy that included small‐scale mobility, which is consistent with the proposed strategy. By harvesting three or four lakes and stocks, fishers increased their yield compared with exploiting one fishing ground and one vendace stock. Public ownership provided fishers access to stocks nearer their place of residence than other ownership types.
Increasing EMMPRIN and matriptase expression in hepatocellular carcinoma: tissue microarray analysis of immunohistochemical scores with clinicopathological parameters
Authors: Tsai W‐C , Chao Y‐C , Lee W‐H , Chen A , Sheu L‐F , Jin J‐S
Published: August 2006

Aims To examine the expression of extracellular matrix metalloprotease inducer (EMMPRIN) and matriptase in hepatocellular carcinoma (HCC) and to correlate this with tumour progression.

Methods and results Immunohistochemical analysis of EMMPRIN and matriptase was performed on tissue microarrays of 122 cases of HCC with various histological grades and/or clinical parameters. The expression of EMMPRIN and matriptase was undetectable in normal liver parenchyma of all eight control cases. However, among the 122 HCC cases, EMMPRIN and matriptase immunoreactivity was seen on the cell membrane and in the cytoplasm. The average immunostaining scores of EMMPRIN were 88 for grade I HCC, 195 for grade II HCC and 293 for grade III HCC. Of 85 HCC cases in 122 with detailed clinical TNM stages, the average immunostaining scores of EMMPRIN were 75 for stage T1, 177 for stage T2, 260 for stage T3 and 313 for stage T4 cases of HCC. In addition, the average immunostaining scores of matriptase were 84 for grade I HCC, 187 for grade II HCC, 302 for grade III HCC, and 72 for stage T1, 181 for stage T2, 224 for stage T3 and 284 for stage T4 cases of HCC. More advanced M and N stages of HCC were associated with higher intensity, greater percentages of tumour staining and immunostaining scores of EMMPRIN and matriptase. Higher EMMPRIN and matriptase immunostaining scores in HCCs also correlated significantly with tumour grading and TNM stages.

Conclusions Our findings demonstrate for the first time that EMMPRIN and matriptase are overexpressed in HCC. These may be novel biomarkers for the diagnosis and treatment of HCC.
The effect of temperature on viscosity of root canal sealers
Authors: Lacey S. , Pitt Ford T. R. , Yuan X.‐F. , Sherriff M. , Watson T.
Published: August 2006

Aim  To test the hypothesis that there was no significant (α = 0.05) change in viscosity of commercially available root canal sealers with increase in temperature using a high‐performance Advanced Rheometric Expansion System (ARES) rheometer.

Methodology  Materials tested were Apexit, Tubliseal EWT, Grossman's, AH Plus and Ketac‐endo. Cone‐and‐plate geometry was used (25‐mm diameter, 0.1 radian and gap 0.051 mm). Measurements were carried out for steady‐state viscosity at 25 and 37 °C in the shear rate range of 0.001–50 s−1 at standardized relative humidity and within 30 min from the start of mixing. Five samples were taken for each sealer at each temperature.

Results  At 25 °C all sealers demonstrated shear thinning. At 37 °C Grossman's (powder : liquid ratio 2 : 1 and 3 : 1) and Ketac‐endo had a rapid rise in viscosity and early set whereas the other sealers were shear thinning. On increasing temperature from 25 °C to 37 °C, Apexit, Tubliseal and AH Plus had reduced viscosity whereas Grossman's 2 : 1, Grossman's 3 : 1 and Ketac‐endo had increased viscosity, which varied with the shear rate. The change in viscosity with change in temperature was significant (P < 0.05) for all sealers except AH Plus.

Conclusions  There was a variation in the effect of increasing temperature on each sealer depending on the shear rate. With the exception of AH Plus, a significant (P < 0.05) change in viscosity was found, and the null hypothesis was rejected.
In vitro antimicrobial activity of sodium hypochlorite and chlorhexidine against selected single‐species biofilms
Authors: Sena N. T. , Gomes B. P. F. A. , Vianna M. E. , Berber V. B. , Zaia A. A. , Ferraz C. C. R. , Souza‐Filho F. J.
Published: August 2006

Aim  To investigate the antimicrobial activity of 2.5% and 5.25% sodium hypochlorite and 2.0% chlorhexidine gel and liquid as endodontic‐irrigating substances against selected single‐species biofilms.

Methods  Single‐species biofilms of Enterococcus faecalis, Staphylococcus aureus, Candida albicans, Prevotella intermedia, Porphyromonas gingivalis, Porphyromonas endodontalis and Fusobacterium nucleatum were generated on a cellulose nitrate membrane placed on agar medium. The biofilms were then immersed in the endodontic‐irrigating substances for 30 s and also for 5, 10, 15, 30 and 60 min, with and without mechanical agitation. Sterile saline was used as control. After each time period, the membrane filters were then transferred to tubes containing 2 mL of fresh broth medium plus neutralizers (in order to prevent the residual action of the tested substances). The micro‐organisms were suspended using a vortex, and the inoculum was serially diluted 10‐fold. Aliquots of the dilutions were plated on 5% sheep blood agar medium, and incubated under adequate gaseous conditions. Colony‐forming units were calculated. The samples were compared using the Friedman and Tukey test, when necessary, at a significance level of P < 0.05.

Results  Mechanical agitation promoted the effectiveness of the antimicrobial agents, resulting in less time to eliminate the same micro‐organisms, except for S. aureus with 2.5% NaOCl. Antimicrobial agents in liquid presentation, especially 5.25% NaOCl and 2% chlorhexidine, killed the tested micro‐organisms more rapidly. Saline did not inhibit the growth of any of the tested micro‐organisms, with or without agitation, being statistically different (P < 0.05) from NaOCl and chlorhexidine. P. intermedia, P. gingivalis, P. endodontalis and F. nucleatum were eliminated in 30 s by all antimicrobial agents, with our without agitation, in contrast with the facultative and aerobe strains.

Conclusions  Mechanical agitation improved the antimicrobial properties of the chemical substances tested using a biofilm model, favouring the agents in liquid presentation, especially 5.25% NaOCl and 2% chlorhexidine.
Survival of root filled cracked teeth in a tertiary institution
Authors: Tan L. , Chen N. N. , Poon C. Y. , Wong H. B.
Published: August 2006

Aim  To assess the survival rate of root filled cracked teeth over a 2‐year period in a tertiary institute.

Methodology  Forty‐nine patients who had root canal treatment completed on their cracked teeth at the National Dental Centre (Singapore) were recalled for a 2‐year review. Collected review data included presence of periodontal pocketing, sinus tract and swelling associated with the teeth. The date of extraction was noted if a tooth was missing at review. Pre‐treatment data collected were number, extent and location of crack, presence of periodontal pocketing, patients’ age and gender, location of cracked teeth, type of teeth and presence of terminal cracked tooth.

Results  Fifty teeth in 49 patients were included. The Kaplan–Meier estimate of 2‐year survival rate was 85.5% (95% confidence interval: 75.5–95.5). Cracked teeth which were the terminal teeth in the dental arch (RR = 4.9, 95% CI: 1.2–2.0, P = 0.04), teeth with pre‐root filling periodontal pocketing (RR = 4.9, 95% CI: 1.2–2.0, P = 0.04) and teeth with multiple cracks (RR = ∞, 95% CI: 1.9–∞, P = 0.01) were more likely to be extracted.

Conclusions  Within the limitations of this study, multiple cracks, terminal teeth and pre‐root filling pocketing were significant prognostic factors for the survival of root filled cracked teeth.
Early exposure to smoking and future fecundity among Danish twins
Authors: Jensen T. K. , Joffe M. , Scheike T. , Skytthe A. , Gaist D. , Petersen I. , Christensen K.
Published: August 2006

Several studies have examined the effect of in utero exposure to smoking and fecundity among the offspring but the findings are contradictory. We therefore studied the waiting time to first pregnancy (TTP) and exposure to smoking in utero and childhood among Danish twins born between 1931 and 1952. Information about TTP, exposure to mothers smoking in pregnancy, exposure to smoking in childhood and current smoking among the male twins and smoking in their own pregnancy among female twins was collected by interview. Fecundability odds ratio (FOR) estimating the odds of conception in a cycle among exposed compared to the unexposed were calculated separately for female and male twins. A total of 1653 female and 1598 male twins reported a TTP. Female twins, exposed in utero, had reduced fecundability after control for confounders (FOR = 0.81; 95% CI 0.67–0.99). A nonsignificant increase in fecundity among male twins exposed to smoking in utero was found (FOR = 1.12; 95% CI 0.89–1.40). Among dizygotic twins of opposite sex sharing the same in utero exposures, the future fecundity of the male twin was unaffected by in utero exposure (FOR = 0.97; 95% CI 0.60–1.55) whereas the female twin had reduced fecundity (FOR = 0.65; 95% CI 0.47–0.91). This study supports that smoking is hazardous to the female fetus not only in the short term but also affects her future ability to conceive and makes it even more important to advise pregnant women to stop smoking.
The biogeography of naturalization in alien plants
Authors: Pyšek Petr , Richardson David M.
Published: August 2006

Aim This paper reviews the main geographical determinants of naturalization in plants.

Location Global.

Methods Comparative studies of large data sets of alien floras are the main source of information on global patterns of naturalization.

Results Temperate mainland regions are more invaded than tropical mainland regions but there seems to be no difference in invasibility of temperate and tropical islands. Islands are more invaded than the mainland. The number of naturalized species in temperate regions decreases with latitude and their geographical ranges increase with latitude. The number of naturalized species on islands increases with temperature. Naturalized species contribute to floristic homogenization, but the phenomenon is scale‐dependent.

Main conclusions Some robust patterns are evident from currently available data, but further research is needed on several aspects to advance our understanding of the biogeography of naturalization of alien plants. For example, measures of propagule pressure are needed to determine the invasibility of communities/ecosystems/regions. The patterns discussed in this paper are derived largely from numbers and proportions of naturalized species, and little is known about the proportion of introduced species that become naturalized. Further insights on naturalization rates, i.e. the proportion of aliens that successfully naturalize within regions, and on geographical and other determinants of its variation would provide us with better understanding of the invasion process. Comparative studies, and resulting generalizations, are almost exclusively based on numbers of species, but alien species differ in their impact on native biodiversity and ecosystem processes.
Hyperthermia is a surrogate marker of inflammation‐mediated cause of brain damage in acute ischaemic stroke
Authors: LEIRA R. , RODRÍGUEZ‐YÁÑEZ M. , CASTELLANOS M. , BLANCO M. , NOMBELA F. , SOBRINO T. , LIZASOAIN I. , DÁVALOS A. , CASTILLO J.
Published: August 2006

The influence of temperature on the outcome observed in experimental models of ischaemic stroke has not been definitively proved in patients with stroke. Interleukin‐6 (IL‐6) acts as important endogenous pyrogen, and it is an important regulator of spontaneous body temperature during cerebral ischaemia. The objective of this study was to determine, during the acute phase of cerebral ischaemia, the potential relationship between proinflammatory cytokines and hyperthermia as a cause of larger cerebral infarcts.

Patients and methods.  We studied 229 patients with a first‐ever acute hemispheric infarction admitted within the first 24 h from onset of symptoms. On admission, axillary temperature was recorded and blood chemistry studies and cranial computed tomography were performed. We classified body temperature into two groups: hyperthermia (37.5 °C) and normothermia (<37.5 °C). We determined proinflammatory markers [IL‐6, tumour necrosis factor‐α (TNF‐α), intercellular adhesion molecule (ICAM‐1) and vascular cellular adhesion molecule] on admission. Two outcome variables were evaluated: (i) infarct volume; (ii) Canadian Stroke Scale (CSS) at 3 months (CSS  7 was considered poor outcome and CSS > 7 good outcome).

Results.  Patients with hyperthermia had higher infarct volume [46.5 (9.8–78.5) cm3 vs. 19.1 (5.0–23.5) cm3; P < 0.0001], as well as poor outcome at 3 months. Plasma levels of IL‐6, TNF‐α and ICAM‐1 were significantly higher in the group of patients with hyperthermia than in the normothermic group. There was a significant correlation between body temperature on admission and infarct volume (r = 0.302; P < 0.0001), and between proinflammatory markers (IL‐6 and TNF‐α) and infarct volume. A significant association was also found between proinflammatory markers (IL‐6, TNF‐α, and ICAM‐1) and poor outcome. However, after adjustment for potential confounders, hyperthermia was not independently associated with either larger infarct volume or with poor outcome at 3 months.

Conclusions.  Inflammatory mediators play a role in acute ischaemic brain damage independently of hyperthermia.
Clinical aspects of parvovirus B19 infection
Authors: BROLIDEN K. , TOLFVENSTAM T. , NORBECK O.
Published: August 2006

Parvovirus B19 is a significant human pathogen that causes a wide spectrum of clinical complications ranging from mild, self‐limiting erythema infectiosum in immunocompetent children to lethal cytopenias in immunocompromised patients and intrauterine foetal death in primary infected pregnant women. The infection may also be persistent and can mimic or trigger autoimmune inflammatory disorders. Another important clinical aspect to consider is the risk of infection through B19‐contaminated blood products. Recent advances in diagnosis and pathogenesis, new insights in the cellular immune response and newly discovered genotypes of human parvoviruses form a platform for the development of modern therapeutic and prophylactic alternatives.
A genomic scan for divergent selection in a secondary contact zone between Atlantic and Gulf of Mexico oysters,Crassostrea virginica
Authors: MURRAY MARIA C. , HARE MATTHEW P.
Published: August 2006

The degree of population structure within species often varies considerably among loci. This makes it difficult to determine whether observed variance reflects neutral‐drift stochasticity or locus‐specific selection at one or more loci. This uncertainty is exacerbated when evolutionary equilibrium cannot be assumed and/or admixture potentially inflates genomic variance. Thus, the value of a ‘genome scan’, where locus‐specific summary statistics are compared with a simulated neutral distribution among loci, may be limited in secondary contact zones if the null distribution is sensitive to the timing of secondary contact. Of particular interest here is the wide variance previously observed in locus‐specific patterns of population structure between Atlantic and Gulf of Mexico populations of eastern oyster,Crassostrea virginica. To test the robustness of an equilibrium null model, we compared among‐locus distributions ofFSTsimulated under migration‐drift equilibrium and several nonequilibrium secondary contact histories. We then tested for evidence of divergent selection between two oyster populations on either side of a secondary contact zone using 215 amplified fragment length polymorphism (AFLP) loci. Constant‐migration equilibrium and nonequilibrium secondary‐contact simulations produced equivalent distributions ofFSTwhen anchored by the global meanFSTobserved in oysters, 0.0917. The 99th quantile of simulated neutralFSTencompassed most of the variation among oyster loci. Three AFLP loci exhibitedFSTvalues higher than this threshold. Although no locus was significant after correcting for multiple tests, our results show in geographically clinal organisms: AFLPs can efficiently characterize the genomic distribution ofFST; equilibrium models can be used to evaluate outliers; these procedures help focus research on genomic regions of interest.
Site‐specific genetic divergence in parallel hybrid zones suggests nonallopatric evolution of reproductive barriers
Authors: PANOVA M. , HOLLANDER J. , JOHANNESSON K.
Published: August 2006

The evolution of reproductive isolation in the presence of gene flow is supported by theoretical models but rarely by data. Empirical support might be gained from studies of parallel hybrid zones between interbreeding taxa. We analysed gene flow over two hybrid zones separating ecotypes ofLittorina saxatilisto test the expectation that neutral genetic markers will show site‐specific differences if barriers have evolvedin situ. Distinct ecotypes found in contrasting shore habitats are separated by divergent selection and poor dispersal, but hybrid zones appear between them. Swedish islands formed by postglacial uplift 5000 years ago provide opportunities to assess genetic structure in a recently evolved system. Each island houses a discrete population containing subpopulations of different ecotypes. Hybrid zones between ecotypes may be a product of ecological divergence occurring on each island or a consequence of secondary overlap of ecotypes of allopatric origin that have spread among the islands. We used six microsatellite loci to assess gene flow and genetic profiles of hybrid zones on two islands. We found reduced gene flow over both hybrid zones, indicating the presence of local reproductive barriers between ecotypes. Nevertheless, subpopulations of different ecotypes from the same island were genetically more similar to each other than were subpopulations of the same ecotype from different islands. Moreover, neutral genetic traits separating the two ecotypes across hybrid zones were site‐specific. This supports a scenario ofin situorigin of ecotypes by ecological divergence and nonallopatric evolution of reproductive barriers.
Genetic divergence in the small Indian mongoose (Herpestes auropunctatus), a widely distributed invasive species
Authors: THULIN CARL‐GUSTAF , SIMBERLOFF DANIEL , BARUN ARIJANA , MCCRACKEN GARY , PASCAL MICHEL , ISLAM M. ANWARUL
Published: August 2006

The combination of founder events, random drift and new selective forces experienced by introduced species typically lowers genetic variation and induces differentiation from the ancestral population. Here, we investigate microsatellite differentiation between introduced and native populations of the small Indian mongoose (Herpestes auropunctatus). Many expectations based on introduction history, such as loss of alleles and relationships among populations, are confirmed. Nevertheless, when applying population assignment methods to our data, we observe a few specimens that are incorrectly assigned and/or appear to have a mixed ancestry, despite estimates of substantial population differentiation. Thus, we suggest that population assignments of individuals should be viewed as tentative and that there should be agreement among different algorithms before assignments are applied in conservation or management. Further, we find no congruence between previously reported morphological differentiation and the sorting of microsatellite variation. Some introduced populations have retained much genetic variation while others have not, irrespective of morphology. Finally, we find alleles from the sympatric grey mongoose (Herpestes edwardsii) in one small Indian mongoose within the native range, suggesting an alternative explanation for morphological differentiation involving a shift in female preferences in allopatry.
Nearshore fish (Pholis gunnellus) persists across the North Atlantic through multiple glacial episodes
Authors: HICKERSON M. J. , CUNNINGHAM C. W.
Published: August 2006

The intertidal biota of the North Atlantic is characterized by two disjunct communities (North American and European) exposed to different climatic regimes during the Pleistocene and in the Holocene. We collect multilocus DNA sequence data from the nearshore fish Pholis gunnellus to help uncover processes determining biogeographical persistence during periodic coastal glaciations. Coalescent‐based estimates from the multilocus DNA sequence data suggest that P. gunnellus persisted on both sides of the North Atlantic throughout the last two glacial maxima (> 202 000 years) with little trans‐Atlantic gene flow since divergence, very little structure among populations within Europe (ΦST < 0.05) and some structure within the North American coastline (ΦST = 0.0–0.21). Although the ecological flexibility and high local migration of P. gunnellus could have enhanced this species’ survival across the Atlantic, logistic regression did not find a significant determinant of trans‐Atlantic persistence when considering 12 other North Atlantic phylogeographical studies from the literature.
Genetic structure of the star sea squirt, Botryllus schlosseri, introduced in southern European harbours
Authors: LÓPEZ‐LEGENTIL SUSANNA , TURON XAVIER , PLANES SERGE
Published: August 2006

The introduction of new genetic variants or species is often caused by maritime transport between harbours. Botryllus schlosseri is a cosmopolitan ascidian species that is found in both harbours and open shore habitats. In order to determine the influence of ship traffic on the genetic structure and phylogeography of B. schlosseri in southern Europe, we analyzed the variability of a fragment of the mitochondrial gene cytochrome c oxidase subunit I (COI). We sampled seven Atlanto‐Mediterranean harbour populations and three open‐shore populations. In addition, we sequenced some colonies from the US‐Atlantic coast and from other Mediterranean localities to perform phylogenetic analyses. Although the number of polymorphic sites recorded (25.8%) was within the range observed in other population studies based on ascidian COI sequences, the haplotypic diversity (16 haplotypes out of 181 sequences) was much lower. Moreover, a lack of intermediate haplotypes was observed. This pattern of high nucleotide diversity and low haplotype diversity was consistent with introduction events of a few divergent haplotypes. We found a strong genetic structure in the study populations. Gene flow was only appreciable between some harbour populations. Harbour‐ and open‐shore populations were well differentiated, although there was no evidence for isolation by distance. A nested clade analysis pointed to long‐distance colonization, possibly coupled with subsequent fragmentation, as the underlying process. Our results suggest that B. schlosseri entered the study area via harbour‐hopping, possibly through recurrent introduction events. The haplotypes from North America and most of the European ones were grouped in the same phylogenetic clade. This suggests occasional gene flow between both continents, probably through ship transport.
From genes to geography: a genetic similarity rule for arthropod community structure at multiple geographic scales
Authors: BANGERT R. K. , ALLAN G. J. , TUREK R. J. , WIMP G. M. , MENESES N. , MARTINSEN G. D. , KEIM P. , WHITHAM T. G.
Published: August 2006

We tested the hypothesis that leaf modifying arthropod communities are correlated with cottonwood host plant genetic variation from local to regional scales. Although recent studies found that host plant genetic composition can structure local dependent herbivore communities, the abiotic environment is a stronger factor than the genetic effect at increasingly larger spatial scales. In contrast to these studies we found that dependent arthropod community structure is correlated with both the cross type composition of cottonwoods and individual genotypes within local rivers up to the regional scale of 720 000 km2 (Four Corner States region in the southwestern USA). Across this geographical extent comprising two naturally hybridizing cottonwood systems, the arthropod community follows a simple genetic similarity rule: genetically similar trees support more similar arthropod communities than trees that are genetically dissimilar. This relationship can be quantified with or without genetic data in Populus.
The tandem GTPase, Der, is essential for the biogenesis of 50S ribosomal subunits in Escherichia coli
Authors: Hwang Jihwan , Inouye Masayori
Published: August 2006

A unique GTP‐binding protein, Der contains two consecutive GTP‐binding domains at the N‐terminal region and its homologues are highly conserved in eubacteria but not in archaea and eukaryotes. In the present paper, we demonstrate that Der is one of the essential GTPases in Escherichia coli and that the growth rate correlates with the amount of Der in the cell. Interestingly, both GTP‐binding domains are required at low temperature for cell growth, while at high temperature either one of the two domains is dispensable. Result of the sucrose density gradient experiment suggests that Der interacts specifically with 50S ribosomal subunits only in the presence of a GTP analogue, GMPPNP. The depletion of Der accumulates 50S and 30S ribosomal subunits with a concomitant reduction of polysomes and 70S ribosomes. Notably, Der‐depleted cells accumulate precursors of both 23S and 16S rRNAs. Moreover, at lower Mg2+ concentration, 50S ribosomal subunits from Der‐depleted cells are further dissociated into aberrant 50S ribosomal subunits; however, 30S subunits are stable. It was revealed that the aberrant 50S subunits, 40S subunits, contain less ribosomal proteins with significantly reduced amounts of L9 and L18. These results suggest that Der is a novel 50S ribosome‐associated factor involved in the biogenesis and stability of 50S ribosomal subunits. We propose that Der plays a pivotal role in ribosome biogenesis possibly through interaction with rRNA or rRNA/r–protein complex.
The affinity of the FimH fimbrial adhesin is receptor‐driven and quasi‐independent of Escherichia coli pathotypes
Authors: Bouckaert Julie , Mackenzie Jenny , De Paz José L. , Chipwaza Beatrice , Choudhury Devapriya , Zavialov Anton , Mannerstedt Karin , Anderson Jennifer , Piérard Denis , Wyns Lode , Seeberger Peter H. , Oscarson Stefan , De Greve Henri , Knight Stefan D.
Published: August 2006

Type‐1 fimbriae are important virulence factors for the establishment of Escherichia coli urinary tract infections. Bacterial adhesion to the high‐mannosylated uroplakin Ia glycoprotein receptors of bladder epithelium is mediated by the FimH adhesin. Previous studies have attributed differences in mannose‐sensitive adhesion phenotypes between faecal and uropathogenic E. coli to sequence variation in the FimH receptor‐binding domain. We find that FimH variants from uropathogenic, faecal and enterohaemorrhagic isolates express the same specificities and affinities for high‐mannose structures. The only exceptions are FimHs from O157 strains that carry a mutation (Asn135Lys) in the mannose‐binding pocket that abolishes all binding. A high‐mannose microarray shows that all substructures are bound by FimH and that the largest oligomannose is not necessarily the best binder. Affinity measurements demonstrate a strong preference towards oligomannosides exposing Manα1‐3Man at their non‐reducing end. Binding is further enhanced by the β1‐4‐linkage to GlcNAc, where binding is 100‐fold better than that of α‐d‐mannose. Manα1‐3Manβ1‐4GlcNAc, a major oligosaccharide present in the urine of α‐mannosidosis patients, thus constitutes a well‐defined FimH epitope. Differences in affinities for high‐mannose structures are at least 10‐fold larger than differences in numbers of adherent bacteria between faecal and uropathogenic strains. Our results imply that the carbohydrate expression profile of targeted host tissues and of natural inhibitors in urine, such as Tamm‐Horsfall protein, are stronger determinants of adhesion than FimH variation.
Multiple large filament bundles observed in Caulobacter crescentus by electron cryotomography
Authors: Briegel Ariane , Dias D. Prabha , Li Zhuo , Jensen Rasmus B. , Frangakis Achilleas S. , Jensen Grant J.
Published: August 2006

While the absence of any cytoskeleton was once recognized as a distinguishing feature of prokaryotes, it is now clear that a number of different bacterial proteins do form filaments in vivo. Despite the critical roles these proteins play in cell shape, genome segregation and cell division, molecular mechanisms have remained obscure in part for lack of electron microscopy‐resolution images where these filaments can be seen acting within their cellular context. Here, electron cryotomography was used to image the widely studied model prokaryote Caulobacter crescentus in an intact, near‐native state, producing three‐dimensional reconstructions of these cells with unprecedented clarity and fidelity. We observed many instances of large filament bundles in various locations throughout the cell and at different stages of the cell cycle. The bundles appear to fall into four major classes based on shape and location, referred to here as ‘inner curvature’, ‘cytoplasmic’, ‘polar’ and ‘ring‐like’. In an attempt to identify at least some of the filaments, we imaged cells where crescentin and MreB filaments would not be present. The inner curvature and cytoplasmic bundles persisted, which together with their localization patterns, suggest that they are composed of as‐yet unidentified cytoskeletal proteins. Thus bacterial filaments are frequently found as bundles, and their variety and abundance is greater than previously suspected.
Requirement for the acetyl phosphate pathway in Escherichia coli ATP‐dependent proteolysis
Authors: Mizrahi Itzhak , Biran Dvora , Ron Eliora Z.
Published: August 2006

Protein degradation is a central component of the protein quality control system. Here we show that efficient proteolysis in Escherichia coli requires the active acetyl phosphate pathway. Deletion of this pathway, leading to depletion of acetyl phosphate, results in temperature sensitivity and reduced rate of ATP‐dependent proteolysis. The effect on proteolysis is general, as can be seen from the slowing down of the degradation of unstable proteins, including puromycin‐derived peptides. In addition, reduced intracellular concentrations of acetyl phosphate brings about an increase in the levels of protein aggregates, which contain a wide range of proteins, as expected if a broad spectrum of substrates are involved. Additional outcomes of acetyl phosphate deficiency are elevation in the transcript levels of heat shock genes and increased thermotolerance. In E. coli the acetyl phosphate pathway is the only source of acetyl phosphate, which is a key metabolic compound involved in major cellular processes. In this communication we present evidence for the general role of the acetyl phosphate pathway in protein degradation.
Type IV pili‐mediated secretion modulates Francisella virulence
Authors: Hager Anthony J. , Bolton Diana L. , Pelletier Mark R. , Brittnacher Mitchell J. , Gallagher Larry A. , Kaul Rajinder , Skerrett Shawn J. , Miller Samuel I. , Guina Tina
Published: August 2006

Francisella tularensis are the causative agent of the zoonotic disease, tularaemia. Among four F. tularensis subspecies, ssp. novicida (F. novicida) is pathogenic only for immunocompromised individuals, while all four subspecies are pathogenic for mice. This study utilized proteomic and bioinformatic approaches to identify seven F. novicida secreted proteins and the corresponding Type IV pilus (T4P) secretion system. The secreted proteins were predicted to encode two chitinases, a chitin binding protein, a protease (PepO), and a β‐glucosidase (BglX). The transcription of F. novicida pepO and bglX was regulated by the virulence regulator MglA. Intradermal infection of mice with F. novicida mutants defective in T4P secretion system or PepO resulted in enhanced F. novicida spread to systemic sites. Infection with F. novicida pepO mutants also resulted in increased neutrophil infiltration into the mouse airways. PepO is a zinc protease that is homologous to mammalian endothelin‐converting enzyme ECE‐1. Therefore, secretion of PepO likely results in increased production of endothelin and increased vasoconstriction at the infection site in skin that limits the F. novicida spread. Francisella human pathogenic strains contain a mutation in pepO predicted to abolish its secretion. Loss of PepO function may have contributed to evolution of highly virulent Francisellae.
Interdigital skin lesions of the lower limbs among patients with lymphoedema in an area endemic for bancroftian filariasis
Authors: Dreyer Gerusa , Addiss David , Gadelha Patricia , Lapa Eduardo , Williamson John , Dreyer Annelies
Published: August 2006

Objectives  An estimated 15 million persons suffer from lymphoedema of the leg in filariasis‐endemic areas of the world. A major factor in the progression of lymphoedema severity is the incidence of acute dermatolymphangioadenitis (ADLA), which is triggered by bacteria that gain entry through damaged skin, especially in the toe web spaces (‘interdigital skin lesions’). Little is known about the epidemiology of these skin lesions or about patients’ awareness of them.

Methods  We interviewed and examined 119 patients (89% women) with lymphoedema of the leg in Recife, Brazil, an area endemic for bancroftian filariasis.

Results  We detected 412 interdigital skin lesions in 115 (96.6%) patients (mean, 3.5 lesions per patient, range 0–8). The number of interdigital skin lesions was significantly associated with lymphoedema stage (P < 0.001) and frequency of ADLA (P < 0.0001). Only 20 (16.8%) patients detected their own interdigital skin lesions or considered them abnormal. Patients reported a mean of 3.6 ADLA episodes during the previous 12 months (range, 0–20); reported ADLA incidence was associated with lymphoedema stage (P < 0.0001) and the number of interdigital skin lesions detected by the examining physician (P < 0.0001).

Conclusions  These data suggest that interdigital skin lesions are a significant risk factor for ADLA and that persons with lymphoedema in filariasis‐endemic areas are unaware of their presence or importance. Prevention of ADLA through prompt recognition and treatment of interdigital skin lesions will require that patients be taught to identify lesions, especially between the toes and to recognize them as abnormal.
Pituitary–gonadal hormones and interleukin patterns in leprosy
Authors: Leal Ângela M. O. , Magalhães Patrícia K. R. , Souza Cacilda S. , Foss Norma T.
Published: August 2006

The functional status of pituitary–gonadal hormones and their relationship to the pattern of inflammatory cytokines in the lepromatous (LL/BL) and tuberculoid (TT/BT) poles of leprosy were investigated. Gonadotropins [luteinizing hormone (LH) and follicle‐stimulating hormone (FSH)], interleukin (IL)‐1β, IL‐6, tumour necrosis factor (TNF)‐α and C‐reactive protein (CRP) concentrations and erythrocyte sedimentation rate (ESR) were significantly higher in LL/BL leprosy patients than in controls and were not different from controls in TT/BT patients. LH and FSH were positively correlated with IL‐1β, IL‐6 and TNF‐α, and CRP concentrations and ESR. Testosterone plasma levels were significantly decreased in LL/BL patients and not different in TT/BT patients compared with controls. In addition, testosterone levels were inversely correlated with IL‐6 and TNF‐α. Prolactin plasma levels of both LL/BL and TT/BT patients were not different when compared with those of controls. There was a significant positive correlation between IL‐6 and TNF‐α plasma levels and ESR and CRP concentrations. IL‐1β was positively correlated with ESR but not with CRP. The significant correlations between gonadotropins and testosterone and cytokines in leprosy patients suggest that cytokines may have a direct influence at testicular level and may be of pathogenetic significance in leprosy and in other inflammatory states involving reproductive dysfunction.
Potential Risk Factors Associated with Bovine Spongiform Encephalopathy in Cattle from Schleswig‐Holstein, Germany
Authors: Pottgießer C. , Ovelhey A. , Ziller M. , Kramer M. , Selhorst T. , Conraths F. J.
Published: August 2006

Since the first detection of bovine spongiform encephalopathy (BSE) in homebred cattle in Germany on 26 November 2000, 382 cases have been confirmed until 30 September 2005. Thirty‐two of these cases were reported from the Federal State of Schleswig‐Holstein (SH). There are hypotheses on the routes of infection for German cattle, but only few efforts have been made to assess potential risk factors by epidemiological studies. The purpose of this study was to identify potential risk factors at the farm level for the occurrence of BSE in cattle in SH. By applying the method of indirect standardization, the prevalence of various structural and management parameters of BSE‐affected farms in SH was compared with the prevalence of these parameters in a standard population of cattle farms from SH. The data describing the standard population were obtained by a cross‐sectional study performed in SH in 2003. Data of the BSE case population were available from the central German BSE case database. A possible association of the occurrence of BSE with the feeding of milk replacers to calves was observed. There was a clear indication that the occurrence of BSE was associated with the presence of pigs and/or poultry on the farm. This finding suggests that cross‐contamination of feed or cross‐exposition may have occurred in SH. The results obtained using the indirect standardization analysis were validated by multiple logistic regression. This study indicates that the feedborne path has been the principal route of transmission for the BSE agent in SH.
Myotropic Avian Leukosis Virus subgroup J Infection in a Chicken
Authors: Sironi G. , Manarolla G. , Pisoni G. , Recordati C. , Rampin T.
Published: August 2006

The study describes a highly productive myotropic avian leukosis virus infection (ALV) in a 3‐month‐old female chicken. At necropsy, ascites, hepatic fibrosis and cardiomegaly were seen. Histologically, the most striking lesion was the presence of cytoplasmic basophilic inclusions in myocardial fibers. Immunostaining for ALV group specific antigen p27 revealed a diffuse presence of virus antigen in cardiac myofibers, in smooth muscle fibers of most of the organs, and in rare, pancreatic and ovarian theca cells. Ultrastructurally, myocardial inclusions consisted of clusters of 50–60 nm round particles with interspersed ribosome‐like granules. Numerous C‐type particles were found in intercellular spaces of ALV p27 positive tissues. PCR analyses revealed the presence of both ALV‐E and ALV‐J related sequences. In chicken genome, ALV‐E is usually present as endogenous provirus therefore, the pathological findings observed in this case are considered to be related with the ALV‐J infection. The results of this report further confirm that ALV‐J may be responsible for highly productive myotropic infections.
Distribution and Abundance of Bluetongue Vectors in Sardinia: Comparison of Field Data with Prediction Maps
Authors: Pili E. , Ciuccè S. , Culurgioni J. , Figus V. , Pinna G. , Marchi A.
Published: August 2006

Following the spread of Bluetongue virus (BTV) in many Mediterranean countries during the last 5 years, presence of the main BTV vector, Culicoides imicola Kieffer (Diptera: Ceratopogonidae), was recorded in the region, including the island of Sardinia where the first BT epidemic originally started in the year 2000. Several models were also designed based on climate variables and satellite imaging in order to predict the presence and abundance of BTV vectors across Europe. A 3 years entomological survey (2001–2003) was conducted in the southern part of Sardinia confirming the widespread presence of C. imicola. However, substantial differences in terms of relative abundance were observed between field data and prediction maps based on satellite‐derived climate variables. Distribution of other potential BT vectors, belonging to Culicoides obsoletus Meigen and Culicoides pulicaris Linnaeus groups was also not congruent with model‐based predictions. These results stress the need of taking into account additional environmental factors (such as soil type, land usage, etc.) and local microclimatic conditions, especially related to breeding site requirements of Culicoides species, in order to predict the presence and abundance of BT vectors and to design reliable prediction maps on a local scale.