bluuebunny/crossref_metadata_2025 huggingface dataset:
The impact of climate change on the physical characteristics of the larger lakes in the English Lake District
Authors: GEORGE GLEN , HURLEY MARGARET , HEWITT DIANE
Published: July 2007

1. The larger lakes of the English Lake District have been the subject of intensive scientific study for more than 60 years. Year‐to‐year variations in the weather have recently been shown to have a major effect on their physical characteristics. The area is mild but very wet and the dynamics of the lakes are strongly influenced by the movement of weather systems across the Atlantic.

2. Here, we combine the results of long‐term measurements and the projections from a Regional Climate Model (RCM) to assess the potential impact of climate change on the surface temperature and residence times of the lakes.

3. The RCM outputs used were produced by the U.K. Hadley Centre and are based on the IPCC ‘A2’ scenario for the emission of greenhouse gases. These suggest that winters in the area will be very much milder and wetter by the 2050s and that there will be a pronounced reduction in the summer rainfall.

4. An analysis of the meteorological data acquired between 1940 and 2000 shows that there have been progressive increases in the winter air temperature and in the rainfall which are correlated with the long‐term change in the North Atlantic Oscillation. The trends reported during the summer were less pronounced and were correlated with the increased frequency of anticyclonic days and a decrease in the frequency of westerly days in the British Isles.

5. A simple model of the year‐to‐year variations in surface temperatures showed that the highest winter temperatures were recorded in the deeper lakes and the highest summer temperatures in the lakes with the shallowest thermoclines. When this model was used to predict the surface temperatures of the lakes in the 2050s, the greatest winter increase (+1.08 °C) was observed in the shallowest lake and the greatest summer increase (+2.18 °C) in the lake with the shallowest thermocline.

6. The model used to estimate the seasonal variation in the residence time of the lakes showed that the most pronounced variations were recorded in lakes with a short residence time. Average winter residence times ranged from a minimum of 10 days to a maximum of 436 days and average summer values from a minimum of 23 days to a maximum of 215 days. When this model was used to predict the residence time of the lakes in the 2050s, the greatest winter decrease (−20%) was observed in the smallest lake and the greatest summer increase (+92%) in the lake with the shortest residence time.

7. The results are discussed in relation to trends reported elsewhere in Europe and the impact of changes in the atmospheric circulation on the dynamics of the lakes. The most serious limnological effects were those projected for the summer and included a general increase in the stability of the lakes and a decrease in the flushing rate of the lakes with short residence times.
Phytoplankton production and growth rate in Lake Tanganyika: evidence of a decline in primary productivity in recent decades
Authors: STENUITE STEPHANE , PIRLOT SAMUEL , HARDY MARIE‐ASTRID , SARMENTO HUGO , TARBE ANNE‐LAURE , LEPORCQ BRUNO , DESCY JEAN‐PIERRE
Published: July 2007

1. This study focused on phytoplankton production in Lake Tanganyika. We provide new estimates of daily and annual primary production, as well as growth rates of phytoplankton, and we compare them with values published in former studies.

2. Chlorophyll‐a(chl‐a) in the mixed layer ranged from 5 to 120 mg chl‐a m−2and varied significantly between rainy and dry seasons. Particulate organic carbon concentrations were significantly higher in the south basin (with 196 and 166 mg C m−3in the dry and the rainy season, respectively) than in the north basin (112 and 109 mg C m−3, respectively).

3. Carbon : phosphorus (C : P) ratios varied according to season. Phosphorus limitation seemed to occur more frequently than nitrogen limitation, especially during the rainy season. Severe P deficiencies were rare.

4. Measured particulate daily primary production ranged from 110 to 1410 mg C m−2 day−1; seasonal contrasts were well marked in the north basin, but less in the south basin, where primary production peaks occurred also in the rainy season. Estimates of annual primary production, based on daily primary production calculated from chl‐aand water transparency, gave values lower than those reported in previous studies. Picophytoplankton accounted on average for 56% of total particulate production in the south basin during the wet season of 2003.

5. Phytoplankton growth rates, calculated from primary production, ranged from 0.055 to 0.282 day−1; these are lower than previously published values for Lake Tanganyika.
Combining surveys of river habitats and river birds to appraise riverine hydromorphology
Authors: VAUGHAN I. P. , NOBLE D. G. , ORMEROD S. J.
Published: July 2007

1. Biological monitoring is vital to river conservation. Aside from providing census data, regular monitoring may detect population trends that reflect the degradation or remediation of riverine environments. Birds are major candidates for this purpose because of their connections to riverine food webs and river habitat features. However, much information on factors affecting river bird distributions is qualitative.

2. River bird populations have been surveyed annually in the U.K. since 1974. The value of this monitoring could be increased if links between population trends and changes in riverine landscapes or channel hydromorphology were better understood. We modelled the relationships between bird species’ distributions recorded by the British Trust for Ornithology's Waterways Breeding Bird Survey (WBBS) and hydromorphology recorded by the Environment Agency's River Habitat Survey (RHS).

3. Regression models were built for 20 bird species associated with the river channel and neighbouring floodplains. This provided one of the first illustrations in ecology of generalized estimating equations (GEEs) for extending generalized linear models to instances where individual observations are not statistically independent. GEEs could offer a range of benefits to freshwater biologists, as they are a simple approach to analysing hierarchical, correlated data while maintaining the ease of interpretation with a range of link functions and data types.

4. Upland, fast water species and reedbed specialists showed the closest links with RHS, followed by lowland, slow water species, where correlations to RHS varied widely in magnitude. The distributions of floodplain wading birds were poorly modelled by RHS, suggesting that floodplain land uses as quantified by RHS were poor predictors of distributions. Marked preferences between upland and lowland channels were evident for most species. Specific features were also important, including hydraulics, bank/channel vegetation, depositional features and anthropogenic structures.

5. Monitoring the abundance and distribution of a range of bird species, with a diversity of life histories, could be a valuable tool for assessing trends in riverine landscapes and whole river basins. RHS captures useful information about channel hydromorphology and vegetation, but needs supplementing with additional environmental information to describe (i) the wider riverine landscape (e.g. more detailed floodplain variables, proximity of other waterbodies) and (ii) water chemistry. Although further work is required, this study suggests that WBBS and RHS add mutual value in appraising the river environment. We advocate the further development of birds as indicators in riverine landscapes that could convey the importance of the ecological integrity, biological production and conservation value of river systems to a wider audience.
EMG study for perioral facial muscles function during mastication
Authors: HANAWA S. , TSUBOI A. , WATANABE M. , SASAKI K.
Published: July 2007

Abstract  This study aimed to clarify the temporal and quantitative modulation in the orbicularis oris (OO) and buccinator (BUC) muscle activities during mastication. Ten healthy males (26.9 ± 1.0 years) participated. Electromyograms (EMGs) of the facial muscles were recorded with fine wire electrodes when chewing the chewing gum (one to four sticks) and peanuts (one to five pieces). Surface EMGs of the masseter (MAS) and digastric muscles were recorded simultaneously. EMGs of the OO and BUC showed rhythmic single‐peaked bursts corresponding to the jaw‐opening phase of chewing cycles. The total cycle lengths were constant regardless of the food amount. Integrated EMGs of the OO changed significantly when the amount of both foods changed (anova: P < 0.05). Those of the BUC changed significantly with the amount of gum changed (P < 0.05), but did not change with the amount of peanuts changed. The burst duration of OO changed significantly when the amount of gum changed during ipsilateral chewing (P < 0.05). When the amount of peanuts changed during ipsilateral chewing, the onset of OO and the peak of BUC based on the onset of MAS activity changed significantly (P < 0.05). However, the onset, peak and offset of the OO and BUC based on the offset of MAS did not change regardless of the amounts chewed. The changes of the OO and BUC activities may derive from chewing‐generated sensory inputs in accordance with the physical property of food in part, which would relate to the function of these muscles during mastication.
Treatment outcomes of dental injury diagnoses as related to blood flow measurements from teeth
Authors: EMSHOFF R. , MOSCHEN I. , STROBL H.
Published: July 2007

Summary  The purpose of this study was to investigate whether dental injury diagnoses may predict adverse outcomes occurring 102 weeks after trauma, and to evaluate whether the severity of adverse outcome is related to laser Doppler flowmetry (LDF) measurements of blood flow from teeth. In 309 trauma patients, 404 permanent maxillary incisors and the respective contralateral homologous control teeth were investigated clinically and radiographically, and by LDF to assess local blood flow values. Dental displacement injuries were classified as grade I (subluxation), grade II (lateral or extrusive luxation), and grade III (avulsion or intrusive luxation). Dental fracture injuries were classified as uncomplicated crown fractures, complicated crown fractures, and root fracture. An adverse outcome was defined as the presence of ‘periapical radiolucency and/or grey discolouration’. Significant increase in risk of an adverse outcome occurred with a grade II dental displacement injury (15·07 odds ratio; P = 0·000), a grade III dental displacement injury (28·33 odds ratio; P = 0·000), and a root fracture (106·25 odds ratio; P = 0·000). Blood flow measurements that were significantly associated with more severe outcome were blood flow levels of ≤3 perfusion units (PU; 170·72 odds ratio; P = 0·000), and those of >3 PU and ≤6 PU (76·71 odds ratio; P = 0·000). Diagnoses of displaced and root fractured teeth predicted dental injury patients who went on to show adverse treatment outcomes of splinting. Blood flow measurements from teeth were related to the severity of adverse outcome.
Attitudes, awareness and oral health‐related quality of life in patients with diabetes
Authors: ALLEN E. M. , ZIADA H. M. , O’HALLORAN D. , CLEREHUGH V. , ALLEN P. F.
Published: July 2007

Summary  The purpose of this study was to assess the knowledge diabetic patients have of their risk for periodontal disease, their attitude towards oral health and their oral health‐related quality of life (OHRQL). One hundred and one consecutive patients (age range 31–79 years) recruited from a diabetic outpatient clinic participated in the study. Twenty‐seven per cent of participants had type 1 diabetes, 66% type 2 and 7% did not know what type of diabetes they had. The length of time since participants were diagnosed as diabetic ranged from 1 to 48 years. Metabolic control of diabetes as determined by HbA1c levels ranged from 6·2% to 12·0% compared with the normal range of 4·5–6·0%. Thirty‐three per cent of participants were aware of their increased risk for periodontal disease, 84% of their increased risk for heart disease, 98% for eye disease, 99% for circulatory problems and 94% for kidney disease. Half of the participants who were aware of their increased risk for periodontal disease had received this information from a dentist. Dental attendance was sporadic, with 43% reporting attendance within the last year. OHRQL was not significantly affected by the presence of diabetes in the group surveyed, in comparison with a previous survey of non‐diabetic patients. A significant association was found between metabolic control and dentate status. Awareness of the potential associations between diabetes, oral health and general health needs to be increased in diabetic patients.
The prevalence and severity of non‐carious cervical lesions in a group of patients attending a university hospital in Trinidad
Authors: SMITH W. A. J. , MARCHAN S. , RAFEEK R. N.
Published: July 2007

Summary  Non‐carious cervical lesions (NCCLs) are often encountered in clinical practice and their aetiology attributed to toothbrush abrasion, erosion and tooth flexure. This paper aims to determine the prevalence and severity of NCCLs in a sample of patients attending a university clinic in Trinidad and to investigate the relationship with medical and dental histories, oral hygiene practices, dietary habits and occlusion. Data were collected via a questionnaire and clinical examination. Odds ratios were used to determine the association of the presence of lesions and the factors examined. One hundred and fifty‐six patients with a mean age of 40·6 years were examined of whom 62·2% had one or more NCCLs. Forty five per cent of the lesions were sensitive to compressed air. Younger age groups had a significantly lower correlation with the presence of NCCLs than older age groups. Other significant factors included patients who reported heartburn, gastric reflux, headaches, bruxism, sensitive teeth and swimming or had a history of broken restorations in the last year. There was also significant correlation of NCCLs in patients who brushed more than once a day or used a medium or hard toothbrush. Patients with vegetarian diets and those who reported consuming citrus fruits, soft drinks, alcohol, yoghurt and vitamin C drinks were associated with the presence of lesions. Significant associations were also found in patients with group function, faceting, clicking joints or those who wore occlusal splints.
Magnetic resonance imaging of ankle tendons and ligaments: Part I – Anatomy
Authors: Kong A , Cassumbhoy R , Subramaniam RM
Published: July 2007

Magnetic resonance imaging is an excellent technique for imaging the tendons and the ligaments of the ankle. Owing to the advantage of detailed demonstration of soft‐tissue structures and capability for multiplanar demonstration of the ankle ligaments and tendons, MRI has been increasingly used in the evaluation of the ligamentous and the tendon injuries of the ankle. Knowledge of normal anatomy and of MRI appearances are essential to recognize pathological appearances. In this pictorial essay, the first of a three part series, we review the normal MRI appearances of the ankle tendons and ligaments. The anterior, lateral and medial tendon groups, the Achilles tendon and the lateral, the syndesmotic and the medial ligament groups are described and illustrated. Anatomy of the sinus tarsi is also described. Tendon and ligament pathology will be illustrated in the second part of the series, and imaging approach to ankle injuries will be outlined in the final part of this series.
Comparison of CT and positron emission tomography/CT coregistered images in planning radical radiotherapy in patients with non‐small‐cell lung cancer
Authors: MacManus M , D’Costa I , Everitt S , Andrews J , Ackerly T , Binns D , Lau E , Ball D , Weih L , Hicks RJ
Published: July 2007

Imaging with F‐18 fluorodeoxyglucose positron emission tomography (PET) significantly improves lung cancer staging, especially when PET and CT information are combined. We describe a method for obtaining CT and PET images at separate acquisitions, which allows coregistration and incorporation of PET information into the radiotherapy (RT) planning process for non‐small‐cell lung cancer. The influence of PET information on RT planning was analysed for 10 consecutive patients. Computed tomography and PET images were acquired with the patient in an immobilization device, in the treatment position. Using specially written software, PET and CT data were coregistered using fiducial markers and imported into our RT planning system (Cadplan version 6). Treatment plans were prepared with and without access to PET/CT coregistered images and then compared. PET influenced the treatment plan in all cases. In three cases, geographic misses (gross tumour outside planning target volume) would have occurred had PET not been used. In a further three cases, better planning target volume marginal coverage was achieved with PET. In four patients, three with atelectasis, there were significant reductions in V20 (percentage of the total lung volume receiving 20 Gy or more). Use of coregistered PET/CT images significantly altered treatment plans in a majority of cases. This method could be used in routine practice at centres without access to a combined PET/CT scanner .
Correlation between parathyroid hormone, bone alkaline phosphatase and N‐telopeptide of type 1 collagen in diabetic and non‐diabetic haemodialysis patients
Authors: TAKAHASHI NOBUNORI , KOJIMA TOSHIHISA , OGAWA HIROSHI , ISHIGURO NAOKI
Published: July 2007

Background:  Haemodialysis (HD) patients with diabetes mellitus often have renal osteodystrophy (ROD) characterized by reduced bone turnover, but little is known about the correlation between bone formation and bone resorption in this population.

Methods:  The authors measured serum parathyroid hormone (PTH), bone alkaline phosphatase (BAP), N‐telopeptides of type 1 collagen (NTx) and fasting glucose in 48 patients with diabetic nephropathy (DN) and 80 patients with glomerulonephritis (non‐DN) who had received ≤10 years of regular HD. Spearman's correlation coefficients (r) were derived.

Results:  In the whole patients, the DN group had a lower PTH and NTx level than the non‐DN group. Serum PTH was not correlated with NTx in the DN group, whereas all three markers were correlated with each other in the non‐DN group. Subdividing the DN patients according to HD duration revealed remarkable differences in the correlation between BAP and NTx: in patients receiving ≥5 years HD (r = 0.568) this correlation was similar to that in the non‐DN group (r = 0.653), whereas there was no significant correlation in those receiving <5 years HD. Patients receiving ≥5 years HD had a comparable glucose level (111.1 ± 19.2 mg/dL) to the non‐DN group, whereas those receiving <5 years had a higher level (196.1 ± 53.1 mg/dL).

Conclusion:  Differences in the interaction between bone cells between DN and non‐DN patients are one potential cause of lower bone turnover in the former group. Research of this correlation is needed to increase understanding of the complexities of bone metabolism in DN patients.
Separating the determinants of phylogenetic community structure
Authors: Helmus Matthew R. , Savage Kristina , Diebel Matthew W. , Maxted Jeffrey T. , Ives Anthony R.
Published: July 2007

The role of competition in forbidding similar species from co‐occurring has long been debated. A difficulty in identifying this repulsion of similar species is that similar species share similar environmental requirements and hence show an attraction to communities where these requirements are met. To disentangle these opposing patterns, we use phylogenetic relatedness as an objective metric of species similarities. Studying 11 sunfishes (Centrarchidae) from 890 lakes, we first show no phylogenetic pattern in the raw community data. We then regressed sunfish presence/absence against seven environmental variables and show that lakes with similar water clarity and latitude likely contain closely related species. After statistically removing the environmental effects, phylogenetic repulsion was apparent, with closely related sunfishes less likely to co‐occur. Thus, both phylogenetic attraction, driven by environmental filtering, and phylogenetic repulsion, possibly caused by competition, simultaneously occur and obscure one another in the overall phylogenetic structure of sunfish communities.
A comparative study of the cytometric characteristics of High and Low nucleic‐acid bacterioplankton cells from different aquatic ecosystems
Authors: Bouvier Thierry , Del Giorgio Paul A. , Gasol Josep M.
Published: July 2007

Flow cytometry has revealed the existence of two distinct fractions of bacterioplankton cells, characterized by high and low nucleic acid contents (HNA and LNA cells). Although these fractions seem ubiquitous in aquatic systems, little is known concerning the variation in the cytometric parameters used to characterize them. We have performed cytometric analyses of samples from a wide range of aquatic systems to determine the magnitude and variability in the cytometric characteristics of HNA/LNA. We show that neither group is associated to a fixed level of fluorescence and of light scatter. Rather, the relative position of HNA and LNA in the fluorescence versus side scatter cytograms varies greatly, both within and among ecosystems. Although the cytometric parameters of both groups tend to covary, there is often uncoupling between the two, particularly in light scatter. Our results show that, although the basic HNA/LNA configuration is present in most samples, its cytometric expression changes greatly in different ecosystems and along productivity gradients. The patterns in cytometric parameters do not support the simple, dichotomous view of HNA and LNA as active and inactive cells, or the notion of two distinct and independent communities, but rather suggest that there may be cells that are intrinsic to each fraction, as well as others that may exchange between fractions.
Postreplicative Formation of Cohesion Is Required for Repair and Induced by a Single DNA Break
Authors: Ström Lena , Karlsson Charlotte , Lindroos Hanna Betts , Wedahl Sara , Katou Yuki , Shirahige Katsuhiko , Sjögren Camilla
Published: July 2007

Sister-chromatid cohesion, established during replication by the protein complex cohesin, is essential for both chromosome segregation and double-strand break (DSB) repair. Normally, cohesion formation is strictly limited to the S phase of the cell cycle, but DSBs can trigger cohesion also after DNA replication has been completed. The function of this damage-induced cohesion remains unknown. In this investigation, we show that damage-induced cohesion is essential for repair in postreplicative cells in yeast. Furthermore, it is established genome-wide after induction of a single DSB, and it is controlled by the DNA damage response and cohesin-regulating factors. We thus define a cohesion establishment pathway that is independent of DNA duplication and acts together with cohesion formed during replication in sister chromatid–based DSB repair.
Efficient Tandem Polymer Solar Cells Fabricated by All-Solution Processing
Authors: Kim Jin Young , Lee Kwanghee , Coates Nelson E. , Moses Daniel , Nguyen Thuc-Quyen , Dante Mark , Heeger Alan J.
Published: July 2007

Tandem solar cells, in which two solar cells with different absorption characteristics are linked to use a wider range of the solar spectrum, were fabricated with each layer processed from solution with the use of bulk heterojunction materials comprising semiconducting polymers and fullerene derivatives. A transparent titanium oxide (TiO
x
) layer separates and connects the front cell and the back cell. The TiO
x
layer serves as an electron transport and collecting layer for the first cell and as a stable foundation that enables the fabrication of the second cell to complete the tandem cell architecture. We use an inverted structure with the low band-gap polymer-fullerene composite as the charge-separating layer in the front cell and the high band-gap polymer composite as that in the back cell. Power-conversion efficiencies of more than 6% were achieved at illuminations of 200 milliwatts per square centimeter.
Magmatic Gas Composition Reveals the Source Depth of Slug-Driven Strombolian Explosive Activity
Authors: Burton Mike , Allard Patrick , Muré Filippo , La Spina Alessandro
Published: July 2007

Strombolian-type eruptive activity, common at many volcanoes, consists of regular explosions driven by the bursting of gas slugs that rise faster than surrounding magma. Explosion quakes associated with this activity are usually localized at shallow depth; however, where and how slugs actually form remain poorly constrained. We used spectroscopic measurements performed during both quiescent degassing and explosions on Stromboli volcano (Italy) to demonstrate that gas slugs originate from as deep as the volcano-crust interface (∼3 kilometers), where both structural discontinuities and differential bubble-rise speed can promote slug coalescence. The observed decoupling between deep slug genesis and shallow (∼250-meter) explosion quakes may be a common feature of strombolian activity, determined by the geometry of plumbing systems.
Extraordinary Flux in Sex Ratio
Authors: Charlat Sylvain , Hornett Emily A. , Fullard James H. , Davies Neil , Roderick George K. , Wedell Nina , Hurst Gregory D. D.
Published: July 2007

The ratio of males to females in a species is often considered to be relatively constant, at least over ecological time. Hamilton noted that the spread of "selfish" sex ratio-distorting elements could be rapid and produce a switch to highly biased population sex ratios. Selection against a highly skewed sex ratio should promote the spread of mutations that suppress the sex ratio distortion. We show that in the butterfly Hypolimnas bolina the suppression of sex biases occurs extremely fast, with a switch from a 100:1 population sex ratio to 1:1 occurring in fewer than 10 generations.
Cleaving Mercury-Alkyl Bonds: A Functional Model for Mercury Detoxification by
MerB
Authors: Melnick Jonathan G. , Parkin Gerard
Published: July 2007

The extreme toxicity of organomercury compounds that are found in the environment has focused attention on the mechanisms of action of bacterial remediating enzymes. We describe facile room-temperature protolytic cleavage by a thiol of the Hg-C bond in mercury-alkyl compounds that emulate the structure and function of the organomercurial lyase
MerB
. Specifically, the tris(2-mercapto-1-
t
-butylimidazolyl)hydroborato ligand [Tm

Bu
t

], which features three sulfur donors, has been used to synthesize [Tm

Bu
t

]HgR alkyl compounds (R = methyl or ethyl) that react with phenylthiol (PhSH) to yield [Tm

Bu
t

]HgSPh and RH. Although [Tm

Bu
t

]HgR compounds exist as linear two-coordinate complexes in the solid state,
1
H nuclear magnetic resonance spectroscopy indicates that the complexes exist in rapid equilibrium with their higher-coordinate [κ
2
-Tm

Bu
t

]HgR and [κ
3
-Tm

Bu
t

]HgR isomers in solution. Facile access to a higher-coordinate species is proposed to account for the exceptional reactivity of [Tm

Bu
t

]HgR relative to that of other two-coordinate mercury-alkyl compounds.
Improved Enzyme-Linked Immunosorbent Assay To RevealMycoplasma agassiziiExposure: a Valuable Tool in the Management of Environmentally Sensitive Tortoise Populations
Authors: Wendland Lori D. , Zacher Laurie A. , Klein Paul A. , Brown Daniel R. , Demcovitz Dina , Littell Ramon , Brown Mary B.
Published: July 2007

The precarious status of desert (Gopherus agassizii) and gopher (Gopherus polyphemus) tortoises has resulted in research and conservation efforts that include health assessments as a substantial component of management decision-making. Therefore, it is critical that available diagnostic tests for diseases impacting these species undergo rigorous standardization and validation. Since 1992, analysis of exposure of tortoises toMycoplasma agassizii, an etiological agent of upper respiratory tract disease, has relied on the detection of specificM. agassiziiantibody by enzyme-linked immunosorbent assay (ELISA). We report here substantive refinements in the diagnostic assay and discuss the implications of its use in wildlife conservation and management. The ELISA has been refined to include more stringent quality control measures and has been converted to a clinically more meaningful titer reporting system, consistent with other diagnostic serologic tests. The ELISA results for 5,954 desert and gopher tortoises were plotted, and a subset of these serum samples (n= 90) was used to determine end-point titers, to establish an optimum serum dilution for analyzing samples, and to construct a standard curve. The relationship between titer andA405was validated using 77 serum samples from known positive (n= 48) and negative (n= 29) control tortoises from prior transmission studies. The Youden index,J, and the optimal cut point,c, were estimated using ELISA results from the 77 control sera. Based on this evaluation, the refinement has substantially improved the performance of the assay (sensitivity of 0.98, specificity of 0.99, andJof 0.98), thus providing a clinically more reliable diagnostic test for this important infection of tortoises.
Genotypic Analysis of Varicella-Zoster Virus and Its Seroprevalence in Finland
Authors: Koskiniemi Marjaleena , Lappalainen Maija , Schmid D. Scott , Rubtcova Elena , Loparev Vladimir N.
Published: July 2007

We evaluated the seroprevalence of varicella-zoster virus (VZV) in the Finnish population among various age groups and genetically characterized VZV strains from documented cases of varicella and zoster. VZV-specific immunoglobulin G was measured in 2,842 serum samples that had been submitted for virological studies to the Department of Virology, University of Helsinki, from 1995 to 1996. Specimens for VZV genotyping were obtained from vesicular lesions from two pediatric patients and 26 adult patients. Seroprevalence to VZV varied markedly by age: 45% in children aged ≤2 months, 12.5% in children aged 6 to 8 months, and >90% in children near 10 years of age, plateauing thereafter into advanced age. The seroprevalence rates indicate that in Finland, as in other countries with temperate climates, primary VZV infection usually occurs during the first decade of life. Twenty-eight VZV DNA-positive specimens were analyzed to identify VZV vaccine and wild-type genotypes. All analyzed specimens were wild type and the European (E) genotype.
Implementation Validation Performed in Rwanda To Determine Whether the INNO-LiPA Rif.TB Line Probe Assay Can Be Used for Detection of Multidrug-Resistant
Mycobacterium tuberculosis
in Low-Resource Countries
Authors: Quezada Cindy Maria , Kamanzi Eliane , Mukamutara Julienne , De Rijk Pim , Rigouts Leen , Portaels Françoise , Amor Yanis Ben
Published: July 2007

We validated the implementation of the INNO-LiPA Rif.TB line probe assay, a diagnostic test for rapid detection of multidrug-resistant tuberculosis (MDR-TB), in Rwanda. No substantial difference was found between results obtained in Rwanda and results obtained in Belgium with the same samples. This rapid diagnostic test for MDR-TB can therefore be reliably implemented in a resource-poor setting.
New Method for Simultaneous Species-Specific Identification of Equine Strongyles (Nematoda, Strongylida) by Reverse Line Blot Hybridization
Authors: Traversa Donato , Iorio Raffaella , Klei Thomas R. , Kharchenko Vitaliy A. , Gawor Jakub , Otranto Domenico , Sparagano Olivier A. E.
Published: July 2007

The ability of a reverse line blot (RLB) assay to identify 13 common species of equine small strongyles (cyathostomins) and to discriminate them from threeStrongylusspp. (large strongyles) was demonstrated. The assay relied on the specific hybridization of PCR-amplified intergenic spacer DNA fragments of the nuclear ribosomal DNA to membrane-bound species-specific probes. All cyathostomins examined were unequivocally identified and simultaneously discriminated from each other and from three large strongyles (Strongylus edentatus,Strongylus equinus, andStrongylus vulgaris). This assay will enable the accurate and rapid identification of equine cyathostomins irrespective of their life cycle stage, opening important avenues for a better understanding of their biology and epidemiology and of the pathogenesis of cyathostomin-associated disease. In particular, this RLB method promises to be a powerful diagnostic tool to determine the roles of individual species in the pathogenesis of mixed infections and to elucidate some aspects of cyathostominosis. Also, it could represent a basic step toward the development of a rapid and simple molecular test for the early detection of drug-resistant genotypes of horse strongyle species.
Immunity to Avirulent Enterovirus 71 and Coxsackie A16 Virus Protects against Enterovirus 71 Infection in Mice
Authors: Wu Te-Chia , Wang Ya-Fang , Lee Yi-Ping , Wang Jen-Ren , Liu Ching-Chuan , Wang Shih-Min , Lei Huan-Yao , Su Ih-Jen , Yu Chun-Keung
Published: July 2007

In this study, we sought to determine whether intratypic and intertypic cross-reactivity protected against enterovirus 71 (EV71) infection in a murine infection model. We demonstrate that active immunization of 1-day-old mice with avirulent EV71 strain or coxsackie A16 virus (CA16) by the oral route developed anti-EV71 antibodies with neutralizing activity (1:16 and 1:2, respectively). Splenocytes from both EV71- and CA16-immunized mice proliferated upon EV71 or CA16, but not coxsackie B3 virus (CB3), antigen stimulation. Immunized mice became more resistant to virulent EV71 strain challenge than nonimmunized mice. There was an increase in the percentage of activated splenic T cells and B cells in the immunized mice 2 days after EV71 challenge. The CA16 immune serum reacted with EV71 antigens in an enzyme-linked immunosorbent assay and neutralized EV71 but not CB3 or poliovirus at a titer of 1:4. Passive immunization with the CA16 immune serum reduced the clinical score, diminished the organ viral load, and increased the survival rate of mice upon EV71 challenge. CB3 neither shared in vitro cross-reactivity with EV71 nor provided in vivo protection after both active and passive immunization. These results illustrated that live vaccine is feasible for EV71 and that intertypic cross-reactivity of enteroviruses may provide a way to determine the prevalence of EV71.
Autographa californica
Multiple Nucleopolyhedrovirus EXON0 (ORF141) Is Required for Efficient Egress of Nucleocapsids from the Nucleus
Authors: Fang Minggang , Dai Xiaojiang , Theilmann David A.
Published: July 2007

Autographa californica
multiple nucleopolyhedrovirus (AcMNPV)
exon0
(
orf141
) has been shown to be required for the efficient production of budded virus (BV). The deletion of
exon0
reduces the level of BV production by up to 99% (X. Dai, T. M. Stewart, J. A. Pathakamuri, Q. Li, and D. A. Theilmann, J. Virol. 78:9633-9644, 2004); however, the function or mechanism by which EXON0 affects BV production is unknown. In this study, we further elucidated the function of EXON0 by investigating the localization of EXON0 in infected Sf9 cells and in virions and by identifying interactions between EXON0 and other viral proteins. In addition, electron microscopy was used to study the cellular localization of nucleocapsids in cells transfected with an
exon0
knockout (KO) virus. The results showed that EXON0 was localized to both the cytoplasm and the nuclei of infected Sf9 cells throughout the infection. Western blotting results also showed that EXON0 was purified along with BV and occlusion-derived virus (ODV). The fractionation of BV into the nucleocapsid and envelope components showed that EXON0 localized to the BV nucleocapsid. Yeast two-hybrid screening, coimmunoprecipitation, and confocal microscopy revealed that it interacted with nucleocapsid proteins FP25 and BV/ODV-C42. Cells transfected with the
exon0
KO virus exhibited normally appearing nucleocapsids in the nuclei in numbers equal to those in the nuclei of cells transfected with the EXON0 repaired virus. In contrast, the numbers of nucleocapsids in the cytoplasm of cells transfected with the
exon0
KO virus were significantly lower than those in the cytoplasm of cells transfected with the repaired virus. These results support the conclusion that EXON0 is required in the BV pathway for the efficient egress of nucleocapsids from the nucleus to the cytoplasm.
Mutations in the Stalk of the Measles Virus Hemagglutinin Protein Decrease Fusion but Do Not Interfere with Virus-Specific Interaction with the Homologous Fusion Protein
Authors: Corey Elizabeth A. , Iorio Ronald M.
Published: July 2007

The hemagglutinin (H) protein of measles virus (MV) mediates attachment to cellular receptors. The ectodomain of the H spike is thought to consist of a membrane-proximal stalk and terminal globular head, in which resides the receptor-binding activity. Like other paramyxovirus attachment proteins, MV H also plays a role in fusion promotion, which is mediated through an interaction with the viral fusion (F) protein. The stalk of the hemagglutinin-neuraminidase (HN) protein of several paramyxoviruses determines specificity for the homologous F protein. In addition, mutations in a conserved domain in the Newcastle disease virus (NDV) HN stalk result in a sharp decrease in fusion and an impaired ability to interact with NDV F in a cell surface coimmunoprecipitation (co-IP) assay. The region of MV H that determines specificity for the F protein has not been identified. Here, we have adapted the co-IP assay to detect the MV H-F complex at the surface of transfected HeLa cells. We have also identified mutations in a domain in the MV H stalk, similar to the one in the NDV HN stalk, that also drastically reduce fusion yet do not block complex formation with MV F. These results indicate that this domain in the MV H stalk is required for fusion but suggest either that mutation of it indirectly affects the H-dependent activation of F or that the MV H-F interaction is mediated by more than one domain in H. This points to an apparent difference in the way the MV and NDV glycoproteins interact to regulate fusion.
Human Papillomavirus Type 31 Uses a Caveolin 1- and Dynamin 2-Mediated Entry Pathway for Infection of Human Keratinocytes
Authors: Smith Jessica L. , Campos Samuel K. , Ozbun Michelle A.
Published: July 2007

Papillomaviruses are species-specific and epitheliotropic DNA viruses that cause tumors in their natural hosts. Certain infections with genital human papillomavirus (HPV) types are causally related to cervical cancer development. Most papillomaviruses are thought to infect cells via a clathrin-dependent pathway, yet no studies have determined the entry route in permissive host epithelial cells. Employing fluorescently labeled and native virions, we tested the effects of dominant-negative and biochemical inhibitors of cellular endocytosis pathways. Infections of human keratinocytes, a natural host cell type for HPVs, were assessed visually and by infectious entry assays. We found that HPV type 31 (HPV31) entry and initiation of early infection events require both caveolin 1 and dynamin 2 and occur independently of clathrin-mediated endocytosis. Treatment with chlorpromazine and filipin had opposing effects on HPV31 and HPV16 infection. HPV31 entry was remarkably slow, with a half-time of ≈14 h, whereas the entry half-time of HPV16 was 4 h. Consistent with a caveola-mediated entry pathway for HPV31, the virions associated with detergent-resistant lipid rafts. During a 16-h microscopic tracking of HPV31 and HPV16 virions, no colocalization of the two viral types was observed. These data suggest that HPV31 and HPV16 virions use distinct routes for host epithelial cell entry.
Recruitment of Human Cytomegalovirus Immediate-Early 2 Protein onto Parental Viral Genomes in Association with ND10 in Live-Infected Cells
Authors: Sourvinos George , Tavalai Nina , Berndt Anja , Spandidos Demetrios A. , Stamminger Thomas
Published: July 2007

The human cytomegalovirus (HCMV) immediate-early 2 (IE2) transactivator has previously been shown to form intranuclear, dot-like accumulations in association with subnuclear structures known as promyelocytic leukemia protein (PML) nuclear bodies or ND10. We recently observed that IE2 can form dot-like structures even after infection of PML knockdown cells, which lack genuine ND10. To further analyze the determinants of IE2 subnuclear localization, a recombinant HCMV expressing IE2 fused to the enhanced green fluorescent protein was constructed. We infected primary human fibroblasts expressing Sp100 fused to the autofluorescent protein mCherry while performing live-cell imaging experiments. These experiments revealed a very dynamic association of IE2 dots with ND10 structures during the first hours postinfection: juxtaposed structures rapidly fused to precise colocalizations, followed by segregation, and finally, the dispersal of ND10 accumulations. Furthermore, by infecting PML knockdown cells we determined that the number of IE2 accumulations was dependent on the multiplicity of infection. Since time-lapse microscopy in live-infected cells revealed that IE2 foci developed into viral replication compartments, we hypothesized that viral DNA could act as a determinant of IE2 accumulations. Direct evidence that IE2 molecules are associated with viral DNA early after HCMV infection was obtained using fluorescence in situ hybridization. Finally, a DNA-binding-deficient IE2 mutant could no longer be recruited into viral replication centers, suggesting that the association of IE2 with viral DNA is mediated by a direct DNA contact. Thus, we identified viral DNA as an important determinant of IE2 subnuclear localization, which suggests that the formation of a virus-induced nucleoprotein complex and its spatial organization is likely to be critical at the early stages of a lytic infection.
DDB1 and Cul4A Are Required for Human Immunodeficiency Virus Type 1 Vpr-Induced G
2
Arrest
Authors: Tan Lindi , Ehrlich Elana , Yu Xiao-Fang
Published: July 2007

Vpr-mediated induction of G
2
cell cycle arrest has been postulated to be important for human immunodeficiency virus type 1 (HIV-1) replication, but the precise role of Vpr in this cell cycle arrest is unclear. In the present study, we have shown that HIV-1 Vpr interacts with damaged DNA binding protein 1 (DDB1) but not its partner DDB2. The interaction of Vpr with DDB1 was inhibited when DCAF1 (VprBP) expression was reduced by short interfering RNA (siRNA) treatment. The Vpr mutant (Q65R) that was defective for DCAF1 interaction also had a defect in DDB1 binding. However, Vpr binding to DDB1 was not sufficient to induce G
2
arrest. A reduction in DDB1 or DDB2 expression in the absence of Vpr also did not induce G
2
arrest. On the other hand, Vpr-induced G
2
arrest was impaired when the intracellular level of DDB1 or Cullin 4A was reduced by siRNA treatment. Furthermore, Vpr-induced G
2
arrest was largely abolished by a proteasome inhibitor. These data suggest that Vpr assembles with DDB1 through interaction with DCAF1 to form an E3 ubiquitin ligase that targets cellular substrates for proteasome-mediated degradation and G
2
arrest.
Epstein-Barr Virus BHRF1 Micro- and Stable RNAs during Latency III and after Induction of Replication
Authors: Xing Li , Kieff Elliott
Published: July 2007

Epstein-Barr virus (EBV) microRNAs miR-BHRF1-1, -2, and -3 have been detected in latency III-infected lymphoblasts, where they are encoded within EBNA transcripts (X. Cai, A. Schafer, S. Lu, J. P. Bilello, R. C. Desrosiers, R. Edwards, N. Raab-Traub, and B. R. Cullen, PLoS Pathog.
2:
e23, 2006). In latency III-infected lymphoblasts, we have also identified a stable 1.3-kb RNA, which begins 3′ to miR-BHRF1-1, includes the BHRF1 open reading frame, and ends near miR-BHRF1-2. This 1.3-kb RNA is the residue of Drosha cleavage of the BHRF1 microRNAs from EBNA transcripts. Early after induction of EBV replication in latency I-infected Akata lymphoblasts, BHRF1 spliced 1.4-kb mRNA accumulated along with low levels of miR-BHRF1-2 and -3 and a 0.9-kb Drosha or miR-BHRF1-2 cleavage product of BHRF1 mRNA. The turning on of latency III infection at 48 to 72 h after induction of EBV replication was associated with higher miR-BHRF1-1, -2, and -3 levels; accumulation of the 1.3-kb RNA residue in the nucleus; abundant BHRF1 spliced 1.4-kb mRNA in the cytoplasm; and more abundant 0.9-kb mRNA cleavage product in the cytoplasm. These findings implicate miR-BHRF1-2 in 3′ cleavage of BHRF1 mRNA in the cytoplasm and Drosha in cleavage of latency III EBNA and EBV replication-associated BHRF1 transcripts in the nucleus.
The effect of sandstorms and air pollution on cause-specific hospital admissions in Taipei, Taiwan
Authors: Bell M L , Levy J K , Lin Z
Published: July 2007

Objective:

Relatively little research exists focusing on the impact of air pollution on hospital admissions in Asia compared to the extensive work conducted in the USA and Europe. The issue is of particular importance because of the frequency, intensity and health effects of Asian sandstorms. This work investigates the relation between cause-specific hospital admissions and sandstorms and air pollution in Taipei, Taiwan’s capital.

Methods:

Time-series analyses of asthma, pneumonia, ischaemic heart disease and cerebrovascular disease hospital admissions were performed for Taipei. An eight-year time period (1995–2002) was considered for various indicators of sandstorms and the pollutants NO2, CO, ozone, SO2, PM10, and PM2.5. Pollution effects based on single-day lags of 0, 1, 2 and 3 days were explored, along with the average of the same day and previous three days (L03).

Results:

The risk of ischaemic heart disease admissions was associated with several sandstorm metrics, including indicators of high PM10levels in the Taipei area, indicators of high PM10at a monitor designed to measure background pollution, the PM coarse fraction, and the ratio of PM10to PM2.5. However, the lag structure of effect was not consistent across sandstorm indicators. Hospital admissions for this disease were 16–21% higher on sandstorm days compared to other days. This cause was also associated with transportation-related pollutants, NO2, CO and PM2.5. Asthma admissions rose 4.48% (95% CI 0.71% to 8.38%) per 28 μg/m3increase in L03 PM10levels and 7.60% (95% CI 2.87% to 12.54%) per 10 ppb increase in L03 ozone. Cerebrovascular disease admissions were associated with PM10and CO, both at lag 3 days. SO2exhibited no relation with admissions.

Conclusions:

Risk of hospital admissions in Taipei may be increased by air pollution and sandstorms. Additional research is needed to clarify the lag structure and magnitude of such effects.