bluuebunny/crossref_metadata_2025 huggingface dataset:
No overall stimulation of soil respiration under mature deciduous forest trees after 7 years of CO2 enrichment
Authors: BADER MARTIN K.‐F. , KÖRNER CHRISTIAN
Published: February 2010

The anthropogenic rise in atmospheric CO2 is expected to impact carbon (C) fluxes not only at ecosystem level but also at the global scale by altering C cycle processes in soils. At the Swiss Canopy Crane (SCC), we examined how 7 years of free air CO2 enrichment (FACE) affected soil CO2 dynamics in a ca. 100‐year‐old mixed deciduous forest. The use of 13C‐depleted CO2 for canopy enrichment allowed us to trace the flow of recently fixed C. In the 7th year of growth at ∼550 ppm CO2, soil respiratory CO2 consisted of 39% labelled C. During the growing season, soil air CO2 concentration was significantly enhanced under CO2‐exposed trees. However, elevated CO2 failed to stimulate cumulative soil respiration (Rs) over the growing season. We found periodic reductions as well as increases in instantaneous rates of Rs in response to elevated CO2, depending on soil temperature and soil volumetric water content (VWC; significant three‐way interaction). During wet periods, soil water savings under CO2‐enriched trees led to excessive VWC (>45%) that suppressed Rs. Elevated CO2 stimulated Rs only when VWC was ≤40% and concurrent soil temperature was high (>15 °C). Seasonal Q10 estimates of Rs were significantly lower under elevated (Q10=3.30) compared with ambient CO2 (Q10=3.97). However, this effect disappeared when three consecutive sampling dates of extremely high VWC were disregarded. This suggests that elevated CO2 affected Q10 mainly indirectly through changes in VWC. Fine root respiration did not differ significantly between treatments but soil microbial biomass (Cmic) increased by 14% under elevated CO2 (marginally significant). Our findings do not indicate enhanced soil C emissions in such stands under future atmospheric CO2. It remains to be shown whether C losses via leaching of dissolved organic or inorganic C (DOC, DIC) help to balance the C budget in this forest.
High Notch1 protein expression is an early event in breast cancer development and is associated with the HER‐2 molecular subtype
Authors: Zardawi Sarah J , Zardawi Ibrahim , McNeil Catriona M , Millar Ewan K A , McLeod Duncan , Morey Adrienne L , Crea Paul , Murphy Niamh C , Pinese Mark , Lopez‐Knowles Elena , Oakes Samantha R , Ormandy Christopher J , Qiu Min Ru , Hamilton Anne , Spillane Andrew , Soon Lee Cheok , Sutherland Robert L , Musgrove Elizabeth A , O’Toole Sandra A
Published: February 2010

Zardawi S J, Zardawi I, McNeil C M, Millar E K A, McLeod D, Morey A L, Crea P, Murphy N C, Pinese M, Lopez‐Knowles E, Oakes S R, Ormandy C J, Qiu M R, Hamilton A, Spillane A, Soon Lee C, Sutherland R L, Musgrove E A & O’Toole S A (2010) Histopathology56, 286–296

High Notch1 protein expression is an early event in breast cancer development and is associated with the HER‐2 molecular subtype

Aims:  Activation of Notch signalling results in hyperplasia and tumorigenesis in murine mammary epithelium. However, there is little information regarding the expression of Notch1 in premalignant lesions and early breast cancer. We investigated expression of Notch1 in breast cancer development and its association with molecular subtypes.

Methods and results:  Immunohistochemical expression of Notch1 was determined in a murine model of mammary carcinogenesis and in breast tissue from two cohorts of breast cancer patients, the first (n = 222) comprising a histological progression series and the second an outcome series of 228 patients with operable invasive ductal carcinoma. Enhanced expression of Notch1 protein was an early event in both murine and human breast cancer development with progressive increases in expression with the development of hyperplasia and malignancy. High Notch1 was not prognostic in the outcome cohort. There was, however, a highly significant association of high Notch1 protein with the HER‐2 molecular subtype of breast cancer (P = 0.008).

Conclusions:  These data demonstrate that aberrant Notch regulation is an early event in mammary carcinogenesis and is associated with the HER‐2 molecular subtype of breast cancer, and suggest the Notch signalling pathway may be a potential therapeutic target worthy of further investigation.
Small cell carcinoma of the lung and large cell neuroendocrine carcinoma interobserver variability
Authors: Den Bakker Michael A , Willemsen Sten , Grünberg Katrien , Noorduijn L Arnold , Van Oosterhout Matthijs F M , Van Suylen Robert J , Timens Wim , Vrugt Bart , Wiersma‐van Tilburg Anne , Thunnissen Frederik B J M
Published: February 2010

den Bakker M A, Willemsen S, Grünberg K, Noorduijn L A, van Oosterhout M F M, van Suylen R J, Timens W, Vrugt B, Wiersma‐van Tilburg A & Thunnissen F B J M (2010) Histopathology56, 356–363

Small cell carcinoma of the lung and large cell neuroendocrine carcinoma interobserver variability

Aims:  To test the hypothesis that the published morphological criteria permit reliable segregation of small cell carcinoma of the lung (SCLC) and large cell neuroendocrine carcinoma (LCNEC) cases by determining the interobserver variation.

Methods and results:  One hundred and seventy cases of SCLC, LCNEC and cases diagnosed as neuroendocrine lung carcinoma before LCNEC had been established as a diagnostic category were retrieved from the archives of the assessor’s institutes. A representative haematoxylin and eosin section from each case was selected for review. Batches of cases were circulated among nine pathologists with a special interest in pulmonary pathology. Participants were asked to classify the cases histologically according to the 2004 World Health Organization (WHO) criteria. The diagnoses were collected and κ values calculated. Unanimity of diagnosis was achieved for only 20 cases; a majority diagnosis was reached for 115 cases. In 35 cases no consensus diagnosis could be reached. There was striking variability amongst assessors in diagnosing SCLC and LCNEC. The overall level of agreement for all cases included in this study was fair (κ = 0.40).

Conclusions:  Using non‐preselected cases, the morphological WHO criteria for diagnosing SCLC and LCNEC leave room for subjective pathological interpretation, which results in imprecise categorization of SCLC and LCNEC cases.
Assessing reported adherence to pharmacological treatment recommendations. Translation and evaluation of the Medication Adherence Report Scale (MARS) in Germany
Authors: Mahler Cornelia , Hermann Katja , Horne Rob , Ludt Sabine , Haefeli Walter Emil , Szecsenyi Joachim , Jank Susanne
Published: February 2010

Objectives  Patients' self‐report of medicine taking is a feasible method of assessing their adherence to prescribed pharmacological treatment. Aim of this study was to assess whether the German version of the Medication Adherence Report Scale (MARS‐D) is an appropriate instrument for measuring patient adherence.

Methods  After translation into German, the questionnaire was sent to 1488 patients with chronic diseases and patients with risk factors of cardiovascular disease. Reliability and validity of the MARS‐D were assessed and compared with the psychometric properties of the original English version. The relationship between patients' characteristics and adherent behaviour was estimated using bivariate correlation and a linear regression model.

Results  The MARS‐D was analysed if patients were taking medicines and the MARS‐D was complete leaving 523 (35.1%) analysable questionnaires. Internal consistency of the MARS‐D (Cronbach's α 0.60–0.69) was satisfactory and comparable to the English original (Cronbach's α 0.69–0.90). Test–retest reliability was satisfactory (Pearson's r 0.61–0.63), however, lower than in the English sample (r = 0.97). Convergent validity was low but showed statistical significance. Patient socio‐demographic characteristics had weak influence on MARS‐D score indicating high reported adherence for older patients (P < 0.05), patients with German mother tongue (P < 0.05) and high number of medicines (P < 0.01).

Conclusions  Preliminary psychometric evaluation of the MARS‐D is encouraging. MARS‐D is an appropriate measure to detect patients at risk of non‐adherence. The MARS‐D could be used in routine care to support communication about the medication taking behaviour, as self‐report of non‐adherent behaviour corresponds to the facts.
Does the presence of antagonist remaining teeth affect implant overdenture success? A systematic review
Authors: OHKUBO C. , BAEK K. W.
Published: February 2010

Summary  Many patients who need implant overdentures are not completely edentulous; they still have antagonist natural teeth or implant fixed prostheses. In such cases, however, little is known about whether existing natural teeth affect the success of implant overdentures positively or act as a complicating factor. This systematic review attempts to clarify the correlation between existing remaining teeth and the survival/success rate of maxillary and mandibular implant overdentures. An assessment of available relevant articles published in English from 1990 to 2009 was performed using an online database and a manual search in libraries. Although the opposing natural dentition was not sufficiently described in the literature, 10 articles about the mandible and 10 articles about the maxilla were selected. As there was no controlled study on the natural teeth opposing implant overdentures, this review could not reach a clear conclusion. The review did reveal a remarkably high success/survival rate for mandibular implant overdentures; maxillary implant overdentures showed a lower rate. The presence of antagonist teeth hardly seems to be a risk factor for success for mandibular implant overdentures. For maxillary implant overdentures, the existence of antagonist teeth might act negatively for implant survival, but they are certainly not a contraindication. Although a few articles stated this relationship, we could not find an apparent correlation between the remaining antagonist teeth and the success of the implant overdentures. A detailed description of the opposing dentate status and results of randomized controlled clinical trials would be required to characterize this evidence‐based implant overdenture treatment.
Psychosocial impact of Von Hippel–Lindau disease: levels and sources of distress
Authors: Lammens CRM , Bleiker EMA , Verhoef S , Hes FJ , Ausems MGEM , Majoor‐Krakauer D , Sijmons RH , Van Der Luijt RB , Van Den Ouweland AMW , Van Os Tam , Hoogerbrugge N , Gómez García EB , Dommering CJ , Gundy CM , Aaronson NK
Published: February 2010

Lammens CRM, Bleiker EMA, Verhoef S, Hes FJ, Ausems MGEM, Majoor‐Krakauer D, Sijmons RH, Luijt van der RB, Ouweland van den AMW, Van Os Tam, Hoogerbrugge N, Gomez‐Garcia EB, Dommering CJ, Gundy CM, Aaronson NK. Psychosocial impact of von Hippel–Lindau disease: levels and sources of distress.

Von Hippel–Lindau disease (VHL) is a hereditary tumor susceptibility syndrome, characterized by an increased risk of developing multiple benign and malignant tumors at various sites and ages with limited preventive options. This study evaluates the prevalence of distress among VHL family members and factors associated significantly with such distress.

Forty‐eight families with a VHL mutation were identified via the nine family cancer clinics in the Netherlands. In total, 171 family members (carriers, 50% at‐risk, non‐carriers) were approached, of whom 123 (72%) completed a self‐report questionnaire. Approximately 40% of the VHL family members reported clinically relevant levels of distress, approaching 50% among the carriers and, possibly even more striking, 36% among the non‐carriers. Having lost a first degree relative due to VHL during adolescence (OR 11.2; 95% CI 1.4–86.9) was related significantly to heightened levels of distress. Approximately, only one‐third of those who reported heightened levels of distress had received professional psychosocial support. A substantial percentage of family members experience clinically relevant levels of distress. We would recommend the introduction of a procedure for screening for distress in this vulnerable population. Special attention should be paid to those individuals who have lost a close relative due to VHL during adolescence.
Biological structures as a source of habitat heterogeneity and biodiversity on the deep ocean margins
Authors: Buhl‐Mortensen Lene , Vanreusel Ann , Gooday Andrew J. , Levin Lisa A. , Priede Imants G. , Buhl‐Mortensen Pål , Gheerardyn Hendrik , King Nicola J. , Raes Maarten
Published: February 2010

Biological structures exert a major influence on species diversity at both local and regional scales on deep continental margins. Some organisms use other species as substrates for attachment, shelter, feeding or parasitism, but there may also be mutual benefits from the association. Here, we highlight the structural attributes and biotic effects of the habitats that corals, sea pens, sponges and xenophyophores offer other organisms. The environmental setting of the biological structures influences their species composition. The importance of benthic species as substrates seems to increase with depth as the complexity of the surrounding geological substrate and food supply decline. There are marked differences in the degree of mutualistic relationships between habitat‐forming taxa. This is especially evident for scleractinian corals, which have high numbers of facultative associates (commensals) and few obligate associates (mutualists), and gorgonians, with their few commensals and many obligate associates. Size, flexibility and architectural complexity of the habitat‐forming organism are positively related to species diversity for both sessile and mobile species. This is mainly evident for commensal species sharing a facultative relationship with their host. Habitat complexity is enhanced by the architecture of biological structures, as well as by biological interactions. Colony morphology has a great influence on feeding efficiency for suspension feeders. Suspension feeding, habitat‐forming organisms modify the environment to optimize their food uptake. This environmental advantage is also passed on to associated filter‐feeding species. These effects are poorly understood but represent key points for understanding ecosystems and biodiversity on continental margins. In this paper we explore the contributions of organisms and the biotic structures they create (rather than physical modifications) to habitat heterogeneity and diversity on the deep continental margins.
Deep‐water macrofaunal diversity in the Faroe‐Shetland region (NE Atlantic): a margin subject to an unusual thermal regime
Authors: Narayanaswamy Bhavani E. , Bett Brian J. , Hughes David J.
Published: February 2010

The Faroe‐Shetland Channel, situated in the NE Atlantic, encompasses a number of different sediment types (habitats) as well as being subject to an unusual thermal regime. Our main objective was to assess variations in macrofaunal generic diversity and composition along two transects to gauge the relative influence of regional hydrography and local habitat heterogeneity. We found that generic richness and diversity on a West of Shetland (WoS) transect correlated most strongly with temperature range, whilst along a North of Shetland (NoS) transect, richness and diversity correlated negatively with sedimentary variables, notably total organic carbon. Macrofaunal composition at WoS is also strongly influenced by water temperature with specific genera (e.g. Galathowenia positively associated with the temperature eigenvectors), whereas at NoS it is a combination of temperature, silt + clay fraction and total organic carbon that has an impact on composition (e.g. Proclea and Pseudosphyrapus, showing a negative relationship with the temperature eigenvectors). Although the temperature regime exerts a strong control on regional ecology, local habitat heterogeneity remains a significant factor.
Tension‐free vaginal mesh procedure for pelvic organ prolapse: A single‐center experience of 310 cases with 1‐year follow up
Authors: Takahashi Satoru , Obinata Daisuke , Sakuma Takahiro , Nagane Yusuke , Sato Katsuhiko , Mochida Junichi , Ichinose Taketo , Yamaguchi Kenya
Published: February 2010

Objective:  To prospectively evaluate the efficacy of a tension‐free vaginal mesh (TVM) procedure for pelvic organ prolapse (POP).

Methods:  Between December 2005 and April 2008, 310 female patients (mean age 67.2 years, range 42–84) with POP underwent TVM procedures at our institute. Fifty‐six individuals were qualified as stage 2 according to the POP quantification system and 162 and 92 were stage 3 and 4, respectively. One hundred ninety‐one patients underwent anterior TVM, and seven underwent posterior TVM. One hundred twelve cases underwent both anterior and posterior TVM procedures. Each patient was systematically assessed at 1, 3, 6 and 12 months after surgery. Quality of life (QOL) was also assessed by using the Short Form‐36 and the prolapse‐QOL questionnaires.

Results:  Perioperative complications were the following: five bladder injuries (1.6%), no rectal injuries and three hemorrhages greater than 400 mL (1.0%). The anatomical cure rate (% stage 0 cases) at 3, 6 and 12 months after surgery were 94.1%, 93.5%, and 92.3%, respectively. Short Form‐36 and prolapse‐QOL parameters were significantly improved, and maintained during the follow‐up period. Postoperative complications were the following: five pelvic hematomas (1.6%), one wound infection (0.3%), 10 vaginal mesh extrusions (3.2%), and three cases of pelvic pain (1.0%). Complications concerning lower urinary tract function were: eight cases of postoperative stress urinary incontinence (2.6%), three cases of transient urinary retention (1.0%), and two cases of de novo overactive bladder (0.6%).

Conclusions:  The TVM procedure provides a good outcome at 1 year with a low incidence of surgical complications and recurrence. Further evaluation with a longer follow up is needed.
Monitoring and evaluation of refractive error and presbyopia for Vision 2020
Authors: Brian Garry , Du Toit Rènée , Ramke Jacqueline , Palagyi Anna
Published: February 2010

Abstract

Purpose:  To develop output and outcome indicators for the correction of refractive error and presbyopia to a level comparable with those advocated by Vision 2020 for cataract.

Methods:  World Health Organization, Vision 2020 and published eye care intervention literature were searched to find evidence of best practice. This information was used to construct a suite of indicators for monitoring the correction of refractive error and presbyopia.

Results:  Indicators for the monitoring and evaluation of refractive error and presbyopia correction were proposed, addressing refraction and spectacle dispensing outputs and rates, and refractive error correction and presbyopia correction coverage.

Conclusion:  Using data collection that should be occurring in everyday clinical practice, the proposed indicators would provide more comprehensive information than those currently suggested by Vision 2020. As such, they would be more useful in the monitoring and evaluation of the correction of refractive error and presbyopia in the context of Vision 2020.
Perception of tilt following counter‐rotation surgery
Authors: Mehta Jignasa , Farnell Damian JJ , Stappler Theodore , Liazos Efstathios , Wong David
Published: February 2010

Abstract

Background:  Macular translocation surgery (MTS) is one of the treatment options for age‐related macular degeneration (AMD) followed by counter‐rotation surgery (CRS) to correct the resulting tilt. The objective of this paper is to determine the perception of tilt following CRS and identify factors that influence the perception of tilt in the presence of residual cyclorotation following CRS.

Methods:  Thirty‐four AMD patients treated with MTS and CRS were investigated; and all measurements were made preoperatively, and after each surgical procedure. Fundus photographs were analysed with computer software to determine the degree of retinal rotation and reliability was assessed by two independent assessors. The degree of perceptual rotation was measured with Maddox rod and the subjective appreciation of tilt was established by direct questioning. Fixation preference was determined by cover test and convergence. Bagolini glasses were used to determine binocular outcome.

Results:  Post CRS, 20 of the 34 patients had adapted to tilt. There was a significant difference of 5° ± 7° (95% confidence intervals: 1–8°, t = 2.9, degree of freedom = 19, P = 0.008) between the degree of rotation measured from the fundus photographs and the Maddox rod measurement following CRS. Patients with residual retinal rotation less than or equal to 15° did not appreciate tilt in free space. More importantly, fixation with the operated eye and ignoring the image from the non‐operated eye was significantly associated with being free of tilt in natural viewing conditions (P < 0.05).

Conclusion:  Despite the presence of residual cyclorotation of the macula following CRS of up to 27°, a significant proportion (59%) of patients did not perceive the world as tilted in natural viewing conditions. Differences between retinal rotation and perceptual tilt provide evidence of sensory adaptation. It was patients who fixed with their operated eye and ignored the image from the non‐operated eye who did not perceive tilt post CRS.
Role of genetic testing in retinoblastoma management at a tertiary referral centre
Authors: Pradhan Monika A , Ng Yvonne , Strickland Adrienne , George Peter M , Raizis Anthony , Warrington Jenny , Vincent Andrea L
Published: February 2010

Background:  Retinoblastoma (MIM +180 200) is a malignant neoplasm affecting embryonal retina, associated with mutations in the RB1 gene. This paper investigates the results of RB1 testing in retinoblastoma management in a tertiary referral centre.

Methods:  A retrospective audit of genetic testing for retinoblastoma from 2003 to 2008, to determine epidemiology, rate of mutation detection and spectrum was undertaken. Eligible probands were identified from the department database and hospital records examined. DNA extracted from tumour tissue and/or peripheral blood was analysed. All patients and families underwent genetic counselling.

Results:  Twenty patients, including one family, were identified. Eight had bilateral tumours, of whom seven presented before 2 years of age, whereas 10 of 12 unilateral cases presented after 2 years of age. Ten patients (50%) were European, four Maori (20%), three Pacific (15%), two Asian (10%), and one of mixed ancestry (5%). Genetic analysis achieved mutation detection on all affected alleles of all the patients, with tumour tissue available for testing in 19 cases. Ten (40%) had germline mutations (eight bilateral and two unilateral), including one mosaic. 75% of affected Maori had germline mutations compared with 40% Europeans. A wide range of mutations was detected with one novel mutation identified in a familial case.

Conclusion:  Advances in gene testing have enabled a high rate of mutation detection, particularly when tumour tissue is genotyped. Genetic analysis is integral to the management of retinoblastoma patients allowing enhanced follow‐up care, avoidance of unnecessary examinations, family screening, counselling and reproductive planning, with early tumour detection in predisposed individuals.
Antituberculosis medication as a possible epigenetic factor of Leber's hereditary optic neuropathy
Authors: Seo Je Hyun , Hwang Jeong‐Min , Park Sung Sup
Published: February 2010

Abstract

Purpose:  To investigate if antituberculosis medication including ethambutol could be a possible epigenetic factor in visual loss in Leber's hereditary optic neuropathy (LHON).

Methods:  The authors reviewed the medical records of 46 patients registered at Bundang Seoul National University Hospital from 2002 to 2006, who developed the typical clinical neuro‐ophthalmologic features of LHON and possessed a mtDNA mutation at nucleotide 11778, 14484, 3460 or 4171.

Results:  Three of the 46 patients developed visual loss while taking antituberculosis medication. These three patients had the mtDNA 11778 mutation with a mean age of 32.7 years at the onset of visual loss, whereas the mean age of other 43 patients was 21.2 years. One of these three patients was female.

Conclusion:  Antituberculosis medication may be an epigenetic factor of LHON in patients with a primary LHON mutation. This risk should be recognized by physicians and LHON carriers.
The diversity of insectivorous bat assemblages among habitats within a subtropical urban landscape
Authors: HOURIGAN C. L. , CATTERALL CARLA P. , JONES DARRYL , RHODES MARTIN
Published: February 2010

We investigated the bat (Microchiroptera) diversity of four major habitat types within a large Australian subtropical city (Brisbane, Australia) to determine whether species richness was affected by habitat changes associated with urbanization, as suggested from studies elsewhere. Forty sites, ten in each habitat type (remnant bushland, parkland, low‐density residential and high‐density residential) were surveyed using acoustic bat detectors on six non‐consecutive occasions. Fourteen bat species were recorded. The species accumulation curve of the entire Brisbane bat assemblage reached a plateau at 14 species. The total numbers of species in bushland, parkland, low‐density residential and high‐density residential habitats were 14, 13, 14 and 11 species, respectively. Asymptotic estimates of species richness for each habitat were close or equal to these totals. Mean asymptotic estimated species richness differed significantly among habitats, being lowest in high‐density residential sites and highest in low‐density residential sites. Evenness profiles were similar across habitats, and were not strongly dominated by a few species. Partitioning of diversity components showed that landscape (γ) diversity was mainly determined by the high species richness of low‐density residential and bushland habitats (α diversity), rather than high beta (β) diversity among habitats. These findings contradict those of other studies on bat diversity in which species richness was highest within ‘natural’ areas of the urban landscape and assemblages were dominated by one or two species. This highlights the need for caution in making generalizations based on existing information, which is dominated by studies in temperate regions.
Spatial variation in the demography and population dynamics of a perennial shrub (Atriplex vesicaria) under sheep grazing in semi‐arid Australian rangelands
Authors: HUNT L. P.
Published: February 2010

Atriplex vesicaria Heward ex Benth. (Chenopodiaceae) is a widespread perennial shrub in southern Australia's chenopod rangelands but is sensitive to grazing. A detailed investigation of the demography and population dynamics of A. vesicaria under sheep grazing was conducted over 6.5 years at a range of sites across a typical paddock to assess the long‐term effects of grazing on the species and elucidate the mechanisms of population change under grazing. The effects of rainfall on recruitment and mortality were also examined. Six‐monthly censuses of all A. vesicaria individuals were conducted in permanent grazed and ungrazed plots at sites located across an 1100‐ha paddock. Grazing increased adult shrub mortality close to water and reduced recruitment over a broader area of the paddock, but seedling survival did not appear to be affected by grazing. As a result of these changes, the population declined on grazed plots up to 2200 m from water during the study, but the decline was greatest closer to water. The population was most dynamic at the sites furthest from the water point where it was unaffected by grazing because of the greater recruitment and mortality of young plants, but because these processes balanced out over time, population density was effectively unchanged by the end of the study. Although statistical models indicated that six‐monthly rainfall did not explain temporal variation in recruitment or mortality, rainfall nevertheless has a central role in both processes. In particular, longer periods of favourable rainfall and drought appear to have an important influence on recruitment and mortality, respectively, with heavy grazing during a drought period increasing mortality. Occasional shortages of seed or rains occurring during the warmer months when seed germination is limited possibly explain poor recruitment at sites unaffected by grazing following good rainfall.
Limited evidence for ecosystem‐level change on reefs exposed to Haliotis rubra (‘blacklip abalone’) exploitation
Authors: VALENTINE JOSEPH P. , TARBATH DAVID B. , FRUSHER STEWART D. , MUNDY CRAIG N. , BUXTON COLIN D.
Published: February 2010

It is increasingly recognized that fisheries must take the broader ecosystem into account for sustainable management of marine systems, requiring an understanding of the interaction between fished species and other organisms. This study uses a correlative approach to investigate potential interactions between benthic organisms and Haliotis rubra, a dominant herbivore that is the subject of a large and valuable commercial fishery in south‐eastern Australia. Specific emphasis was placed on understanding associations between H. rubra and understorey organisms, because particular understorey algae (crustose coralline algae) provide critical habitat for H. rubra larval recruitment and juvenile ecology. Broad‐scale surveys along the 6–8 m depth contour (the depth range where H. rubra fishing activity is intense) were conducted across four regions (separated by 104−105 m), including at least 10 sites (separated by 102−103 m) within each region. Positive correlations between H. rubra and crustose coralline algae were found, while negative correlations were observed between H. rubra and sessile invertebrates and understorey algae. While significant, these associations were weak and H. rubra abundance generally only explained a small proportion of the variability in the abundance of understorey organisms (r2 0.02–0.30). H. rubra abundance also had a minor influence on community‐level understorey patterns in comparison with differences in community structure attributable to regional variation. Patterns of H. rubra abundance and benthic community structure were also examined in relation to depth at a restricted number of sites. At sites where differences in understorey groups were evident, H. rubra abundance also varied significantly, highlighting the issue of confounding when contrasting patterns of understorey abundance using a correlative approach. Further manipulative experiments are required to confirm causal relationships; however, the available correlative evidence suggests limited ecosystem effects of H. rubra depletion at the scale of individual reefs.
Variation in δ13C among species and sexes in the family Restionaceae along a fine‐scale hydrological gradient
Authors: ARAYA YOSEPH N. , SILVERTOWN JONATHAN , GOWING DAVID J. , MCCONWAY KEVIN , LINDER PETER , MIDGLEY GUY
Published: February 2010

Consistent, repeatable segregation of plant species along hydrological gradients is an established phenomenon that must in some way reflect a trade‐off between plants' abilities to tolerate the opposing constraints of drought and waterlogging. In C3 species tissue carbon isotope discrimination (δ13C) is known to vary sensitively in response to stomatal behaviour, reflecting stomatal limitation of photosynthesis during the period of active growth. However, this has not been studied at fine‐spatial scale in natural communities. We tested how δ13C varied between species and sexes of individuals in the family Restionaceae growing along a monitored hydrological gradient. Twenty Restionaceae species were investigated using species‐level phylogeny at two sites in the Cape Floristic Region, a biodiversity hotspot. A spatial overlap analysis showed the Restionaceae species segregated significantly (P < 0.001) at both sites. Moreover, there were significant differences in δ13C values among the Restionaceae species (P < 0.001) and between male and female individuals of each species (P < 0.01). However, after accounting for phylogeny, species δ13C values did not show any significant correlation with the hydrological gradient. We suggest that some other variable (e.g. plant phenology) could be responsible for masking a simple response to water availability.
Seasonal variation of tadpole spatial niches in permanent streams: The roles of predation risk and microhabitat availability
Authors: ETEROVICK PAULA C. , LAZAROTTI ISABELA , FRANCO BRUNA P. , DIAS CAMILA J.
Published: February 2010

Phenotypic plasticity can improve fitness in unstable environments and can be expressed in many traits, such as life history attributes, growth and behavioural features. Microhabitat choice can have important consequences for development and survival of aquatic organisms and is expected to vary in response to stimuli, such as predation risk, food availability and temperature. At seasonal sites, microhabitat availability and associated benefits may change from season to season, which might lead to altered patterns of microhabitat use by tadpoles. We investigated this hypothesis in 17 streams from two localities in south‐eastern Brazil. We tested whether water level drops significantly during the dry season, whether lower water level results in altered microhabitat availability and whether predation risk changes between seasons, based on predator density. We then tested whether tadpoles change their pattern of microhabitat use, their spatial niche breadth (given by diversity of used microhabitats) and spatial niche overlap (in the case of co‐occurring species). We were able to include in our analyses tadpoles of four species of Hylidae, that occurred throughout both seasons. Stream depth decreased in the dry season, but microhabitat availability remained relatively stable in many streams, and predator density did not change significantly. Tadpoles of three out of the four species studied were more abundant during the dry season, which may be an adaptation to adjust time of metamorphosis to the rainy season. Tadpoles changed their patterns of microhabitat use between seasons, although the potential causing factors investigated did not seem to be responsible. Tadpole plasticity in microhabitat use may indicate the existence of selective pressures that vary through time and space and are still not well understood.
Habitat characteristics predict occupancy patterns of the endangered amphibian Litoria raniformis in flow‐regulated flood plain wetlands
Authors: WASSENS SKYE , HALL ANDREW , OSBORNE WILL , WATTS ROBYN J.
Published: February 2010

Identification of habitat features that are strongly associated with the occurrence of threatened species is important in terms of predicting impacts of habitat change and identifying key habitats for conservation. In this paper, we apply habitat‐based statistical models to predict occupancy patterns of the endangered southern bell frog (Litoria raniformis) across inland New South Wales (Australia). Litoria raniformis previously occupied a wide range of natural and man‐made waterbodies across a large geographic range, including flood plain wetlands, oxbow lagoons, irrigation canals and rice bays. Alteration of natural flooding regimes has affected a large proportion of habitats within the historical range of Litoria raniformis, but it is not clear how these changes have influenced habitat occupancy patterns. Fifty‐two waterbodies were surveyed for presence/absence of Litoria raniformis in 2001 and 2004. Stepwise logistic regression models were generated to select a subset of variables that best predicted occupancy. Using three predictor variables, vacant and occupied habitats could be predicted with an accuracy of 90% and 70%, respectively. The predictor variables were: the interaction between wetland hydrology and complexity of aquatic vegetation, complexity of fringing vegetation and water temperature. While this study demonstrated that a range of waterbody types were occupied by Litoria raniformis, these habitats shared common hydrological conditions and vegetation characteristics. Altered flooding regimes and reductions in the complexity of aquatic and fringing vegetation are likely to increase the probability of localized extinctions of Litoria raniformis populations.
Appearance of Cxcl10‐expressing cell clusters is common for traumatic brain injury and neurodegenerative disorders
Authors: Israelsson Charlotte , Bengtsson Henrik , Lobell Anna , Nilsson Lars N. G. , Kylberg Annika , Isaksson Magnus , Wootz Hanna , Lannfelt Lars , Kullander Klas , Hillered Lars , Ebendal Ted
Published: February 2010

Traumatic brain injury (TBI) in the mouse results in the rapid appearance of scattered clusters of cells expressing the chemokine Cxcl10 in cortical and subcortical areas. To extend the observation of this unique pattern, we used neuropathological mouse models using quantitative reverse transcriptase‐polymerase chain reaction, gene array analysis, in‐situ hybridization and flow cytometry. As for TBI, cell clusters of 150–200 μm expressing Cxcl10 characterize the cerebral cortex of mice carrying a transgene encoding the Swedish mutation of amyloid precursor protein, a model of amyloid Alzheimer pathology. The same pattern was found in experimental autoimmune encephalomyelitis in mice modelling multiple sclerosis. In contrast, mice carrying a SOD1G93A mutant mimicking amyotrophic lateral sclerosis pathology lacked such cell clusters in the cerebral cortex, whereas clusters appeared in the brainstem and spinal cord. Mice homozygous for a null mutation of the Cxcl10 gene did not show detectable levels of Cxcl10 transcript after TBI, confirming the quantitative reverse transcriptase‐polymerase chain reaction and in‐situ hybridization signals. Moreover, unbiased microarray expression analysis showed that Cxcl10 was among 112 transcripts in the neocortex upregulated at least threefold in both TBI and ageing TgSwe mice, many of them involved in inflammation. The identity of the Cxcl10+ cells remains unclear but flow cytometry showed increased numbers of activated microglia/macrophages as well as myeloid dendritic cells in the TBI and experimental autoimmune encephalomyelitis models. It is concluded that the Cxcl10+ cells appear in the inflamed central nervous system and may represent a novel population of cells that it may be possible to target pharmacologically in a broad range of neurodegenerative conditions.
Disturbed structural connectivity is related to inattention and impulsivity in adult attention deficit hyperactivity disorder
Authors: Konrad Andreas , Dielentheis Thomas F. , El Masri Dschamil , Bayerl Martin , Fehr Christoph , Gesierich Thomas , Vucurevic Goran , Stoeter Peter , Winterer Georg
Published: February 2010

Inattention and impulsivity are the most prominent clinical features of attention deficit hyperactivity disorder (ADHD) in adulthood. Structural and functional neuroimaging studies of subjects with ADHD have demonstrated abnormalities in several brain areas, including fronto‐striatal and fronto‐cerebellar networks. Mostly, these studies were based on volumetric measurements and have been conducted in children. We investigated white matter (WM) integrity and correlation with measures of attention and impulsivity in adult patients with ADHD adopting diffusion tensor imaging (DTI). N = 37 (21 males) never‐medicated adult patients with ADHD combined subtype and N = 34 (16 males) healthy controls were investigated. ADHD diagnosis (DSM‐IV) was assessed with clinical interviews and rating scales, subjects also underwent a large neuropsychological test battery including tests of attention and impulsivity. DTI was acquired, and group differences of fractional anisotropy (FA) and mean diffusivity (MD) as well as correlation analyses with measures of attentional performance and impulsivity were calculated using voxel‐based analyses. In adult patients with ADHD, we found reduced FA as well as higher MD bilaterally in orbitomedial prefrontal WM and in the right anterior cingulate bundle, while elevated FA was present bilaterally in temporal WM structures. Measures of attention were correlated with DTI parameters in the right superior longitudinal fasciculus, whereas measures of impulsivity were correlated with FA in right orbitofrontal fibre tracts. This is the first DTI study demonstrating disturbed structural connectivity of the frontal‐striatal circuitry in adult patients with ADHD. Moreover, a direct correlation between WM integrity and measures of attention and impulsivity is shown.
Eye position determines audiovestibular integration during whole‐body rotation
Authors: Van Barneveld Denise C. P. B. M. , John Van Opstal A.
Published: February 2010

When a sound is presented in the free field at a location that remains fixed to the head during whole‐body rotation in darkness, it is heard displaced in the direction opposing the rotation. This phenomenon is known as the audiogyral illusion. Consequently, the subjective auditory median plane (AMP) (the plane where the binaural difference cues for sound localization are perceived to be zero) shifts in the direction of body rotation. Recent experiments, however, have suggested opposite AMP results when using a fixation light that also moves with the head. Although in this condition the eyes remain stationary in the head, an ocular pursuit signal cancels the vestibulo‐ocular reflex, which could induce an additional AMP shift. We tested whether the AMP is influenced by vestibular signals, eye position or eye velocity. We rotated subjects sinusoidally at different velocities, either in darkness or with a head‐fixed fixation light, while they judged the laterality (left vs. right with respect to the midsagittal plane of the head) of broadband sounds presented over headphones. Subjects also performed the same task without vestibular stimulation while tracking a sinusoidally moving visual target, which mimicked the average eye‐movement patterns of the vestibular experiments in darkness. Results show that whole‐body rotation in darkness induces a shift of the AMP in the direction of body rotation. In contrast, we obtained no significant AMP change when a fixation light was used. The pursuit experiments showed a shift of the AMP in the direction of eccentric eye position but not at peak pursuit velocity. We therefore conclude that the vestibular‐induced shift in average eye position underlies both the audiogyral illusion and the AMP shift.
Vasopressin released within the central amygdala promotes maternal aggression
Authors: Bosch Oliver J. , Neumann Inga D.
Published: February 2010

Vasopressin regulates important aspects of social behaviour. Although vasopressin is more prominent in the expression of male social behaviours, we recently demonstrated its role in the fine‐tuned maintenance of maternal care in lactating rats. Here, we investigate the involvement of brain vasopressin in the regulation of maternal aggression in lactating Wistar rats selectively bred for either high (HAB) or low (LAB) anxiety‐related behaviour. The genetically determined elevation in vasopressin mRNA expression was confirmed within the hypothalamic paraventricular nucleus of virgin and lactating HAB rats and was additionally found in limbic brain areas. Lactating HAB dams are more maternally aggressive as part of their generally higher level of maternal care compared with LAB rats. Using intracerebral microdialysis, we describe increased vasopressin release within the central amygdala, but not the paraventricular nucleus, during maternal aggression only in HAB dams. Moreover, the release of vasopressin within the central amygdala was positively correlated with the display of offensive behaviour. Blockade of local vasopressin actions by bilateral administration of a selective vasopressin V1a receptor antagonist into the central amygdala reduced maternal aggression in HAB dams, whereas synthetic vasopressin increased the low level of aggression in LAB rats. Vasopressin receptor binding within the central amygdala or the paraventricular nucleus was similar in HAB and LAB females. In conclusion, vasopressin is an important neuropeptide regulating maternal aggressive behaviour, thus further extending its involvement in female social behaviour. Differences in intracerebral vasopressin release within the central amygdala rather than local vasopressin receptor binding contribute to the level of maternal aggression.
Feature to space conversion during target selection in the dorsolateral and ventrolateral prefrontal cortex of monkeys
Authors: Inoue Masato , Mikami Akichika
Published: February 2010

To investigate the neuronal mechanism of the process of selection of a target from an array of stimuli, we analysed neuronal activity of the lateral prefrontal cortex during the response period of a serial probe reproduction task. During the response period of this task, monkeys were trained to select a memorized target object from an array of three objects and make a saccadic eye movement toward it. Of 611 neurons, 74 neurons showed visual response and 56 neurons showed presaccadic activity during the response period. Among visual neurons, 27 showed array‐ and target‐selectivity. All of these array‐ and target‐selective visual responses were recorded from the ventrolateral prefrontal cortex (VLPFC). Among 56 neurons with presaccadic activity, nine showed target‐selective activity, 17 showed target‐ and direction‐selective activity, and 23 showed direction‐selective activity. The target‐selective, and the target‐ and direction‐selective activities were recorded from the VLPFC, and the direction‐selective activities were recorded from VLPFC and dorsolateral prefrontal cortex (DLPFC). The starting time of the activity was earlier for the target‐selective, and target‐ and direction‐selective activities in VLPFC, intermediate for the direction‐selective activities in VLPFC, and later for the direction‐selective activities in DLPFC. These results suggest that VLPFC plays a role in the process of selection of a target object from an array of stimuli, VLPFC and DLPFC play a role in determining the location of the target in space, and DLPFC plays a role in selecting a direction and making a decision to generate a saccadic eye movement.
Glycine transport accounts for the differential role of glycine vs.d‐serine at NMDA receptor coagonist sites in the salamander retina
Authors: Stevens Eric R. , Gustafson Eric C. , Miller Robert F.
Published: February 2010

In this study, we demonstrate thatd‐serine interacts withN‐methyl‐d‐aspartate receptor (NMDAR) coagonist sites of retinal ganglion cells of the tiger salamander retina by showing that exogenousd‐serine overcomes the competitive antagonism of 7‐chlorokynurenic acid for this site. Additionally, we show that exogenousd‐serine was more than 30 times as effective at potentiating NMDAR currents compared with glycine. We thus examined the importance of glycine transport through the application of selective antagonists of the GlyT1 (NFPS) and GlyT2 (ALX‐5670) transport systems, while simultaneously evaluating the degree of occupancy of the NMDAR coagonist binding sites. Analysis was carried out with electrophysiological recordings from the inner retina, including whole‐cell recordings from retinal ganglion cells and extracellular recordings of the proximal negative field potential. Blocking the GlyT2 transport system had no effect on the light‐evoked NMDAR currents or on the sensitivity of these currents to exogenousd‐serine. In contrast, when the GlyT1 system was blocked, the coagonist sites of NMDARs showed full occupancy. These findings clearly establish the importance of the GlyT1 transporter as an essential component for maintaining the coagonist sites of NMDARs in a non‐saturated state. The normal, unsaturated state of the NMDAR coagonist binding sites allows modulation of the NMDAR currents, by release of eitherd‐serine or glycine. These results are discussed in light of contemporary findings which favord‐serine over glycine as the major coagonist of the NMDARs found in ganglion cells of the tiger salamander retina.