bluuebunny/crossref_metadata_2025 huggingface dataset:
On the coevolution of Ediacaran oceans and animals
Authors: Shen Yanan , Zhang Tonggang , Hoffman Paul F.
Published: May 2008

Fe speciation and S-isotope of pyrite data from the terminal Proterozoic Sheepbed Formation in Canada and Doushantuo Formation in China reveal that ocean deep waters were anoxic after the global glaciations (snowball Earth) ending 635 million years ago, but that marine sulfate concentrations and inferentially atmospheric oxygen levels were higher than before the glaciations. This supports a long-postulated link between oxygen levels and the emergence of eumetazoa. Subsequent ventilation of the deep ocean, inferred from shifts in Fe speciation in Newfoundland (previously published data) and western Canada (this report), paved the way for Ediacaran macrobiota to colonize the deep seafloors.
Physiological Adjustments to Stress Measures Following Massage Therapy: A Review of the Literature
Authors: Moraska Albert , Pollini Robin A. , Boulanger Karen , Brooks Marissa Z. , Teitlebaum Lesley
Published: May 2008

Use of massage therapy by the general public has increased substantially in recent years. In light of the popularity of massage therapy for stress reduction, a comprehensive review of the peer‐reviewed literature is important to summarize the effectiveness of this modality on stress‐reactive physiological measures. On‐line databases were searched for articles relevant to both massage therapy and stress. Articles were included in this review if (i) the massage therapy account consisted of manipulation of soft tissues and was conducted by a trained therapist, and (ii) a dependent measure to evaluate physiological stress was reported. Hormonal and physical parameters are reviewed. A total of 25 studies met all inclusion criteria. A majority of studies employed a 20–30 min massage administered twice‐weekly over 5 weeks with evaluations conducted pre‐post an individual session (single treatment) or following a series of sessions (multiple treatments). Single treatment reductions in salivary cortisol and heart rate were consistently noted. A sustained reduction for these measures was not supported in the literature, although the single‐treatment effect was repeatable within a study. To date, the research data is insufficient to make definitive statements regarding the multiple treatment effect of massage therapy on urinary cortisol or catecholamines, but some evidence for a positive effect on diastolic blood pressure has been documented. While significant improvement has been demonstrated following massage therapy, the general research body on this topic lacks the necessary scientific rigor to provide a definitive understanding of the effect massage therapy has on many physiological variables associated with stress.
Evolutionary ecology during the rise of dioxygen in the Earth's atmosphere
Authors: Sleep Norman H , Bird Dennis K
Published: May 2008

Pre-photosynthetic niches were meagre with a productivity of much less than 10−4of modern photosynthesis. Serpentinization, arc volcanism and ridge-axis volcanism reliably provided H2. Methanogens and acetogens reacted CO2with H2to obtain energy and make organic matter. These skills pre-adapted a bacterium for anoxygenic photosynthesis, probably starting with H2in lieu of an oxygen ‘acceptor’. Use of ferrous iron and sulphide followed as abundant oxygen acceptors, allowing productivity to approach modern levels. The ‘photobacterium’ proliferated rooting much of the bacterial tree. Land photosynthetic microbes faced a dearth of oxygen acceptors and nutrients. A consortium of photosynthetic and soil bacteria aided weathering and access to ferrous iron. Biologically enhanced weathering led to the formation of shales and, ultimately, to granitic rocks. Already oxidized iron-poor sedimentary rocks and low-iron granites provided scant oxygen acceptors, as did freshwater in their drainages. Cyanobacteria evolved dioxygen production that relieved them of these vicissitudes. They did not immediately dominate the planet. Eventually, anoxygenic and oxygenic photosynthesis oxidized much of the Earth's crust and supplied sulphate to the ocean. Anoxygenic photosynthesis remained important until there was enough O2in downwelling seawater to quantitatively oxidize massive sulphides at mid-ocean ridge axes.
A review of effective interventions for reducing aggression and violence
Authors: McGuire James
Published: May 2008

This paper addresses the question of whether individual violence can be reduced in frequency or severity, if so to what extent and by which methods. It opens with a brief overview of the nature of personal violence and discussion of some key definitional and methodological problems. However, its principal focus is on the findings obtained from a series of meta-analytic reviews of structured programmes for adolescents and adults who have shown repeated aggression or been convicted of personal violence, drawing together the results of studies conducted in prison, probation, youth justice and allied services. Additional results are considered from a systematic review of studies of violence prevention among offenders with mental disorders. This incorporates the preliminary findings of a meta-analysis of controlled trials of psychosocial interventions with that population. Overall, it is concluded that there is sufficient evidence currently available to substantiate the claim that personal violence can be reduced by psychosocial interventions, but that much more research is required to delineate the parameters of effectiveness in this context. Proposals are made for future investigations with reference to the theoretical understanding of causal relationships and the design of experimental trials.
Photosynthetic generation of oxygen
Authors: Barber James
Published: May 2008

The oxygen in the atmosphere is derived from light-driven oxidation of water at a catalytic centre contained within a multi-subunit enzyme known as photosystem II (PSII). PSII is located in the photosynthetic membranes of plants, algae and cyanobacteria and its oxygen-evolving centre (OEC) consists of four manganese ions and a calcium ion surrounded by a highly conserved protein environment. Recently, the structure of PSII was elucidated by X-ray crystallography thus revealing details of the molecular architecture of the OEC. This structural information, coupled with an extensive knowledge base derived from a wide range of biophysical, biochemical and molecular biological studies, has provided a framework for understanding the chemistry of photosynthetic oxygen generation as well as opening up debate about its evolutionary origin.
The origin of plastids
Authors: Howe C.J , Barbrook A.C , Nisbet R.E.R , Lockhart P.J , Larkum A.W.D
Published: May 2008

It is generally accepted that plastids first arose by acquisition of photosynthetic prokaryotic endosymbionts by non-photosynthetic eukaryotic hosts. It is also accepted that photosynthetic eukaryotes were acquired on several occasions as endosymbionts by non-photosynthetic eukaryote hosts to form secondary plastids. In some lineages, secondary plastids were lost and new symbionts were acquired, to form tertiary plastids. Most recent work has been interpreted to indicate that primary plastids arose only once, referred to as a ‘monophyletic’ origin. We critically assess the evidence for this. We argue that the combination of Ockham's razor and poor taxon sampling will bias studies in favour of monophyly. We discuss possible concerns in phylogenetic reconstruction from sequence data. We argue that improved understanding of lineage-specific substitution processes is needed to assess the reliability of sequence-based trees. Improved understanding of the timing of the radiation of present-day cyanobacteria is also needed. We suggest that acquisition of plastids is better described as the result of a process rather than something occurring at a discrete time, and describe the ‘shopping bag’ model of plastid origin. We argue that dinoflagellates and other lineages provide evidence in support of this.
A microRNA catalog of the developing chicken embryo identified by a deep sequencing approach
Authors: Glazov Evgeny A. , Cottee Pauline A. , Barris Wesley C. , Moore Robert J. , Dalrymple Brian P. , Tizard Mark L.
Published: May 2008

MicroRNA (miRNA) and other types of small regulatory RNAs play a crucial role in the regulation of gene expression in eukaryotes. Several distinct classes of small regulatory RNAs have been discovered in recent years. To extend the repertoire of small regulatory RNAs characterized in chickens we used a deep sequencing approach developed by Solexa (now Illumina Inc.). We sequenced three small RNA libraries prepared from different developmental stages of the chicken embryo (days five, seven, and nine) to produce over 9.5 million short sequence reads. We developed a bioinformatics pipeline to distinguish authentic mature miRNA sequences from other classes of small RNAs and short RNA fragments represented in the sequencing data. Using this approach we detected almost all of the previously known chicken miRNAs and their respective miRNA* sequences. In addition we discovered 449 new chicken miRNAs including 88 miRNA candidates. Of these, 430 miRNAs appear to be specific to the avian lineage. Another six new miRNAs had evidence of evolutionary conservation in at least one vertebrate species outside of the bird lineage. The remaining 13 putative miRNAs appear to represent chicken orthologs of known vertebrate miRNAs. We discovered 39 additional putative miRNA candidates originating from miRNA generating intronic sequences known as mirtrons.
The β-Glucosidases Responsible for Bioactivation of Hydroxynitrile Glucosides in Lotus japonicus
Authors: Morant Anne Vinther , Bjarnholt Nanna , Kragh Mads Emil , Kjærgaard Christian Hauge , Jørgensen Kirsten , Paquette Suzanne Michelle , Piotrowski Markus , Imberty Anne , Olsen Carl Erik , Møller Birger Lindberg , Bak Søren
Published: May 2008

Lotus japonicus accumulates the hydroxynitrile glucosides lotaustralin, linamarin, and rhodiocyanosides A and D. Upon tissue disruption, the hydroxynitrile glucosides are bioactivated by hydrolysis by specific β-glucosidases. A mixture of two hydroxynitrile glucoside-cleaving β-glucosidases was isolated from L. japonicus leaves and identified by protein sequencing as LjBGD2 and LjBGD4. The isolated hydroxynitrile glucoside-cleaving β-glucosidases preferentially hydrolyzed rhodiocyanoside A and lotaustralin, whereas linamarin was only slowly hydrolyzed, in agreement with measurements of their rate of degradation upon tissue disruption in L. japonicus leaves. Comparative homology modeling predicted that LjBGD2 and LjBGD4 had nearly identical overall topologies and substrate-binding pockets. Heterologous expression of LjBGD2 and LjBGD4 in Arabidopsis (Arabidopsis thaliana) enabled analysis of their individual substrate specificity profiles and confirmed that both LjBGD2 and LjBGD4 preferentially hydrolyze the hydroxynitrile glucosides present in L. japonicus. Phylogenetic analyses revealed a third L. japonicus putative hydroxynitrile glucoside-cleaving β-glucosidase, LjBGD7. Reverse transcription-polymerase chain reaction analysis showed that LjBGD2 and LjBGD4 are expressed in aerial parts of young L. japonicus plants, while LjBGD7 is expressed exclusively in roots. The differential expression pattern of LjBGD2, LjBGD4, and LjBGD7 corresponds to the previously observed expression profile for CYP79D3 and CYP79D4, encoding the two cytochromes P450 that catalyze the first committed step in the biosyntheis of hydroxynitrile glucosides in L. japonicus, with CYP79D3 expression in aerial tissues and CYP79D4 expression in roots.
CressExpress: A Tool For Large-Scale Mining of Expression Data from Arabidopsis
Authors: Srinivasasainagendra Vinodh , Page Grier P. , Mehta Tapan , Coulibaly Issa , Loraine Ann E.
Published: May 2008

CressExpress is a user-friendly, online, coexpression analysis tool for Arabidopsis (Arabidopsis thaliana) microarray expression data that computes patterns of correlated expression between user-entered query genes and the rest of the genes in the genome. Unlike other coexpression tools, CressExpress allows characterization of tissue-specific coexpression networks through user-driven filtering of input data based on sample tissue type. CressExpress also performs pathway-level coexpression analysis on each set of query genes, identifying and ranking genes based on their common connections with two or more query genes. This allows identification of novel candidates for involvement in common processes and functions represented by the query group. Users launch experiments using an easy-to-use Web-based interface and then receive the full complement of results, along with a record of tool settings and parameters, via an e-mail link to the CressExpress Web site. Data sets featured in CressExpress are strictly versioned and include expression data from MAS5, GCRMA, and RMA array processing algorithms. To demonstrate applications for CressExpress, we present coexpression analyses of cellulose synthase genes, indolic glucosinolate biosynthesis, and flowering. We show that subselecting sample types produces a richer network for genes involved in flowering in Arabidopsis. CressExpress provides direct access to expression values via an easy-to-use URL-based Web service, allowing users to determine quickly if their query genes are coexpressed with each other and likely to yield informative pathway-level coexpression results. The tool is available at http://www.cressexpress.org.
Functional Analysis of a Predicted Flavonol Synthase Gene Family in Arabidopsis
Authors: Owens Daniel K. , Alerding Anne B. , Crosby Kevin C. , Bandara Aloka B. , Westwood James H. , Winkel Brenda S.J.
Published: May 2008

The genome of Arabidopsis (Arabidopsis thaliana) contains five sequences with high similarity to FLAVONOL SYNTHASE1 (AtFLS1), a previously characterized flavonol synthase gene that plays a central role in flavonoid metabolism. This apparent redundancy suggests the possibility that Arabidopsis uses multiple isoforms of FLS with different substrate specificities to mediate the production of the flavonols, quercetin and kaempferol, in a tissue-specific and inducible manner. However, biochemical and genetic analysis of the six AtFLS sequences indicates that, although several of the members are expressed, only AtFLS1 encodes a catalytically competent protein. AtFLS1 also appears to be the only member of this group that influences flavonoid levels and the root gravitropic response in seedlings under nonstressed conditions. This study showed that the other expressed AtFLS sequences have tissue- and cell type-specific promoter activities that overlap with those of AtFLS1 and encode proteins that interact with other flavonoid enzymes in yeast two-hybrid assays. Thus, it is possible that these “pseudogenes” have alternative, noncatalytic functions that have not yet been uncovered.
Effect of a new non‐cleavable substrate analog on wild‐type and serine mutants in the signature sequence of adenylosuccinate lyase of Bacillus subtilis and Homo sapiens
Authors: Sivendran Sharmila , Colman Roberta F.
Published: May 2008

Adenylosuccinate lyase (ASL) catalyzes two β‐elimination reactions in purine biosynthesis, leading to the question of whether the two substrates occupy the same or different active sites. Kinetic studies of Bacillus subtilis and human ASL with a new substrate analog, adenosine phosphonobutyric acid, 2′(3′), 5′‐diphosphate (APBADP), show that it acts as a competitive inhibitor with respect to either substrate (KI ∼ 0.1 μM), indicating that the two substrates occupy the same active site. Binding studies show that both the B. subtilis and human ASLs bind up to 4 mol of APBADP per mole of enzyme tetramer and that both enzymes exhibit cooperativity: negative for B. subtilis ASL and positive for human ASL. Mutant B. subtilis ASLs, with replacements for residues previously identified as critical for catalysis, bind the substrate analog similarly to wild‐type ASL. Two serines in a flexible loop of ASL have been proposed to play roles in catalysis because they are close to the substrate in the crystal structure of Escherichia coli ASL. We have now mutated the corresponding serines to alanines in B. subtilis and human ASL to evaluate their involvement in enzyme function. Kinetic data reveal that human Ser289 and B. subtilis Ser262 and Ser263 are essential for catalysis, while the ability of these Ser mutants to bind APBADP suggests that they do not contribute to substrate affinity. Although these serines are not visible in the crystal structure of human adenylosuccinate lyase complexed with substrate or products (PDB #2VD6), they may be interacting with the active sites.
Decreasing delays in urgent and expedited surgery in a university teaching hospital through audit and communication between peri‐operative and surgical directorates
Authors: Cosgrove J. F. , Gaughan M. , Snowden C. P. , Lees T.
Published: May 2008

National Confidential Enquiry into Patient Outcome and Death guidelines for urgent surgery recommend a fully staffed emergency operating theatre and restriction of ‘after‐midnight’ operating to immediate life‐, limb‐ or organ‐threatening conditions. Audit performed in our institution demonstrated significant decreases in waiting times for urgent surgery and an increased seniority of medical care associated with overnight pre‐operative assessment of patients by anaesthetic trainees. Nevertheless, urgent cases continued to be delayed unnecessarily. A classification of delays was developed from existing guidelines and their incidence was audited. The results were disseminated to involved directorates. A repeat of the audit demonstrated a significant decrease in delays (p = 0.001), a significant increase in the availability of surgeons (p = 0.001) and a significant decrease in the median waiting time for urgent surgery compared to the first audit cycle and a previous standard (p < 0.01). We conclude that auditing delays and disseminating the results of the audit significantly decreases delays and median waiting times for urgent surgery because of improved surgical availability.
A survey of inhalational anaesthetic abuse in anaesthesia training programmes*
Authors: Wilson J. E. , Kiselanova N. , Stevens Q. , Lutz R. , Mandler T. , Tran Z. V. , Wischmeyer P. E.
Published: May 2008

This study aims to assess the prevalence and outcomes of inhalational anaesthetic abuse among anaesthesia training programmes. Online surveys were completed by chairpersons of academic anaesthesia training programmes in the United States. The response rate was 84% (106/126 programmes). Twenty‐two percent of the departments had had at least one incident of inhalational anaesthetic abuse. Forty‐eight percent (15/31) of the persons abusing inhalational anaesthetics were sent for rehabilitation. Only 22% (7/31) of those found to be abusing inhalational anaesthetics were ultimately able to return successfully to anaesthesia practice with sustained recovery. The mortality rate among individuals found abusing inhalational anaesthetics was 26% (8/31). The majority of the anaesthesia departments (97/104, 93%) did not have any pharmacy accounting of inhalational anaesthetics. This is the first published survey of inhalational anaesthesia abuse. Inhalational anaesthetic abuse should be considered in at‐risk individuals or those with a history of substance abuse. The concern about substance abuse is not unique to American anaesthetists. Countries around the world deal with similar substance abuse issues.
The natural history of conditional transcranial Doppler flow velocities in children with sickle cell anaemia
Authors: Hankins Jane S. , Fortner Gail L. , McCarville M. Beth , Smeltzer Matthew P. , Wang Winfred C. , Li Chin‐Shang , Ware Russell E.
Published: May 2008

Children with sickle cell anaemia (SCA) and conditional transcranial Doppler (TCD) [time‐averaged mean velocity (TAMV) 170–199 cm/s] have increased risk of primary stroke, but receive no specific therapy. Some will convert to abnormal velocities (TAMV ≥200 cm/s) with further increase in stroke risk. In 2003, our centre initiated universal TCD screening, targeting all children (aged 2–16 years) with SCA. TCD examinations were repeated at intervals based on initial results. To determine rates and risk factors for TCD conversion, we reviewed all examinations since 2003, excluding patients receiving hydroxycarbamide (hydroxyurea) or transfusions. Of the eligible population, 274 children (98%) were screened at a median age of 7·1 years (range 1·7–18·2). Fifty‐four patients (20%) had conditional TAMV either on initial screening or a subsequent examination. The 18‐month cumulative incidence of conversion from conditional to abnormal TAMV was 23%. Age, initial TAMV, laboratory values, blood pressure and oxygen saturation were not significantly associated with conversion. Our cohort provides systematic longitudinal evaluation of an unselected paediatric population universally screened and retested at regular intervals. Our data document a high conversion rate to abnormal velocities among untreated children with SCA. Therapy should be considered for the prevention of conversion to abnormal TCD velocities.
Impact of maternal atopy and probiotic supplementation during pregnancy on infant sensitization: a double‐blind placebo‐controlled study
Authors: Huurre A. , Laitinen K. , Rautava S. , Korkeamäki M. , Isolauri E.
Published: May 2008

Background
The effects of breastfeeding and probiotics on infant sensitization still remain discrepant.

Objective
To explore probable explanatory factors in infant sensitization and the protective effect of probiotics.

Methods
Altogether 171 mother–infant pairs from an ongoing placebo‐controlled double‐blind study with nutrition modulation by dietary counselling and probiotic supplementation were studied. Skin prick testing was done in infants at 6 and 12 months and in mothers at third trimester of pregnancy. The breast milk concentrations of cytokines TGF‐β2, soluble CD14, IFN‐γ, TNF‐α, IL‐10, IL‐6, IL‐4 and IL‐2 were measured.

Results
The risk of sensitization increased in infants with allergic mothers breastfeeding over 6 months [odds ratio (OR=4.83, P=0.005)], or exclusively breastfeeding over 2.5 months (OR=3.4, P=0.018). Probiotic supplementation had a protective effect against sensitization in infants with a high hereditary risk due to maternal sensitization (OR=0.3, P=0.023). The concentration of TGF‐β2 tended to be higher in the colostrum of the mothers in the probiotic group as compared with those on placebo (probiotic/placebo ratio=1.50, P=0.073). A similar result was obtained in the subgroup of allergic mothers (probiotic/placebo ratio=1.56, P=0.094).

Conclusion
Infants of atopic mothers, specifically when breastfed exclusively over 2.5 months or totally over 6 months, had a higher risk of sensitization at the age of 12 months. This risk could be reduced by the use of probiotics during pregnancy and lactation, partly by resulting in a beneficial composition of the breast milk.
Functional consequences of viral impacts on bacterial communities: a food‐web model analysis
Authors: MIKI TAKESHI , NAKAZAWA TAKEFUMI , YOKOKAWA TAICHI , NAGATA TOSHI
Published: May 2008

1. Viruses in aquatic ecosystems can alter the abundance of bacteria and influence organic matter flows and bacterial community composition, but the combined effects of the multiple processes involved in the bacteria‐mediated carbon cycle are not entirely clear.

2. We developed a new conceptual model that incorporates a fundamental but neglected aspect of bacteria–organic matter interactions: that different bacterial groups utilize different kinds of organic matter. In addition, the model incorporates several other realistic features of microbial food webs, including the presence of lysogenic viruses, bacterial resistance to viral infection and dependence of protozoan grazing rate on viral infection.

3. Our model analysis indicates that a ‘viral shunt’ view (i.e. viruses enhance bacterial utilization of organic carbon through regeneration of organic matter but diminish carbon flow to higher trophic levels) is robust, regardless of the specific situations we examined by either incorporating or ignoring various features of microbial food webs.

4. We also found that host‐specific mortality induced by viral infection changes the bacterial utilization of different types of organic matter, which was attributable to diminished ‘apparent competition’ between predator‐sharing bacterial groups that use different carbon sources. This mechanism can facilitate transformation to carbon dioxide of diverse types of carbon sources (e.g. organic matter of algal and terrestrial origin, methane or xenobiotics) and extends the previously recognized roles of viruses in microbial food webs.
Characterization of temperate cyanophages active against freshwater phycocyanin‐rich Synechococcus species
Authors: DILLON AMANDA , PARRY JACQUELINE D.
Published: May 2008

1. This study addressed the prevalence of lysogeny within 19 strains of freshwater Synechococcus sp. rich in phycocyanin (PC) that were isolated from a temperate lake or obtained, in four cases, from a culture collection.

2. Lysis of 16 Synechococcus strains (84%) was inducible with mitomycin C, but the required concentration (20 μg mL−1) was higher than in other studies. Mitomycin C induction yielded burst sizes of 3.5–23.7 phages per cell.

3. Transmission Electron Microscopy of the resultant temperate phages showed that all belonged to the family Siphoviridae with capsid diameters ranging from 40.3 to 53.5 nm and tail lengths from 129 to 186 nm. None of the cyanophages could be maintained in the lytic cycle using the three non‐lysogenic strains, or any of the other 16 lysogenic strains of Synechococcus.

4.These results suggest a potentially high level of lysogeny within PC‐rich Synechococcus species in natural freshwaters, but that the presence of these temperate cyanosiphoviruses may go undetected with the lower mitomycin C concentrations commonly used.
Estimates of bacterial and phytoplankton mortality caused by viral lysis and microzooplankton grazing in a shallow eutrophic lake
Authors: TIJDENS MARJOLIJN , VAN DE WAAL DEDMER B. , SLOVACKOVA HANA , HOOGVELD HANS L. , GONS HERMAN J.
Published: May 2008

1. Since viral lysis and zooplankton grazing differ in their impact on the aquatic food web, it is important to assess the relative importance of both mortality factors. In this study, an adapted version of the dilution technique was applied to simultaneously estimate the impact of both viral lysis and zooplankton grazing on the mortality of heterotrophic bacteria, eukaryotic algae, unicellular cyanobacteria, prochlorophytes and especially filamentous cyanobacteria in a shallow eutrophic lake.

2. Four dilution experiments were performed in December 2004, January 2005, and March and April 2006. Viral and heterotrophic bacterial abundances were obtained by epifluorescence microscopy and abundances of different phytoplankton groups by flow cytometry and light microscopy.

3. Viral lysis was identified as the main mortality cause during the December 2004 and January 2005 experiments, apparently removing between 84% and 97% of the potential filamentous cyanobacterial production and up to 101% of the potential heterotrophic bacterial production. Microzooplankton grazing was estimated to remove between 90% and 99% of the potential unicellular cyanobacterial production and up to 46% of the potential heterotrophic bacterial production during the spring 2006 experiments.

4. In some cases, no significant impact of viral lysis or zooplankton grazing was detected. Contrary to expectations, the apparent growth rate of filamentous cyanobacteria was even sometimes observed to decrease significantly upon dilution of microzooplankton.

5. The dilution technique can give valuable insight into the impact of zooplankton grazing and viral lysis on the mortality of different plankton groups but require some caveats require special care to be taken when comparing and interpreting results.
Variable importance of viral‐induced bacterial mortality along gradients of trophic status and humic content in lakes
Authors: LYMER DAVID , LINDSTRÖM EVA S. , VREDE KATARINA
Published: May 2008

1. The goals of this study were to assess which environmental gradients can be important in predicting viral abundance (VA), the frequency of virus‐infected cells (FVIC) and burst size (BS), and to assess which lake characters favour viral‐induced bacterial mortality (VBM) as opposed to potential grazer‐induced bacterial mortality (PGBM).

2. The epilimnion and hypolimnion of 21 lakes differing in trophic status and humic content were investigated. Samples were obtained for viral and bacterial abundance, the FVIC and burst size, flagellate and ciliate abundances and water chemistry. The potential importance of VBM in relation to PGBM was calculated based on data on FVIC and flagellate and ciliate abundance.

3. Partial least squares regression (PLS) analysis showed that VA as well as the ratio between viral and bacterial abundance were positively related to inorganic nutrient concentrations, dissolved organic carbon concentration, chlorophyll‐a concentration and bacterial production.

4. The PLS model also revealed that FVIC decreased with increasing trophic status whereas BS increased. Furthermore, potential grazing was positively related to increasing trophic status and decreasing humic content. PGBM appeared to be dominating over VBM in the majority of lakes sampled, especially in the epilimnion.

5. Thus, the relative importance of viruses for bacterial mortality was potentially highest in humic lakes of medium trophic status and it was also greater in the hypolimnion than in the epilimnion.
Molecular characterization of the major hemelipoglycoprotein in ixodid ticks
Authors: Donohue K. V. , Khalil S. M. S. , Mitchell R. D. , Sonenshine D. E. , Michael Roe R.
Published: May 2008

The major hemelipoglyco‐carrier protein (CP) found throughout the development of male and female adult American dog ticks, Dermacentor variabilis (Say) was sequenced. DvCP is a single transcript coding for two protein subunits that together contain three motifs: (1) a lipoprotein n‐terminal domain that is a common attribute of proteins that bind lipids, carbohydrates and metals; (2) a domain of unknown function characteristic of proteins with several large open beta sheets; and (3) a von Willebrand factor type D domain near the carboxy‐terminus apparently important for multimerization. These motifs, which are also found in tick vitellogenin, are not shared by heme‐binding proteins studied thus far in other hematophagous insects. DvCP message was highest in fat body and salivary gland but was also found in midgut and ovary tissue. Expression was initiated by blood feeding in virgin females and not by mating, as is typical of tick vitellogenin; and the message was found in fed males at levels similar to part fed, virgin females. CP appears to be highly conserved among the Ixodida. The closest match by BlastP to DvCP is vitellogenin from Caenorhabditis elegans (AAC04423), suggesting that CP is a novel protein. The role of CP in heme sequestration, the evolution of hematophagy and host complementation are discussed.
Corn and rice waste: a comparative and critical presentation of methods and current and potential uses of treated waste
Authors: Arvanitoyannis Ioannis S. , Tserkezou Persefoni
Published: May 2008

Although corn and rice waste can be hardly classified among the most hazardous waste, their treatment is very important in view of the great volume of waste materials involved. In this review article, an update is provided for most of the waste treatment techniques (composting, pyrolysis, gasification, combustion) used to alter the physical, chemical or biological character of the waste, to reduce its volume and/or toxicity and to make the waste safer for disposal. Furthermore, all current and potential uses of treated corn and rice waste such as fertilisers, biomass and biogas/biofuel are summarised. Four comprehensive tables and six figures provide a thorough presentation of both waste treatment methods (characteristics, advantages and disadvantages) and uses of treated corn and rice waste.
Inhibition effects of grape seed extracts on melanosis formation in shrimp (Parapenaeus longirostris)
Authors: Gokoglu Nalan , Yerlikaya Pinar
Published: May 2008

The aim of this study was to investigate the effects of grape seed extracts on inhibition of melanosis in shrimp. Defatted grape seed powder was extracted using ethanol. Dipping solutions in five different concentrations (0, 2.5, 5.0, 10 and 15 g L−1) were prepared using grape seed extract and distilled water. The shrimps were dipped into the solutions and stored at 4 °C. Melanosis was investigated by sensory analysis and lightness, redness and yellowness values were measured by chromometer during the storage for 3 days. According to the results, grape seed extracts showed inhibition effect on the formation of melanosis. The best results were obtained with the solution of 15 g L−1.
Evolution of available lysine and lactose contents in supplemented microencapsulated fish oil infant formula powder during storage
Authors: Chávez‐Servín Jorge Luis , Castellote Ana Isabel , López‐Sabater M. Carmen
Published: May 2008

In this work we report the evolution of available lysine, lactose and lipid hydroperoxide contents as indicators of food quality and stability of two types of infant formula powder stored at 25° and 37 °C for 12 months. The first type was supplemented with microencapsulated fish oil (MFO), made of little powder particles in a food starch‐coated matrix of caseinate and saccharose to prevent the oxidation of polyunsaturated fatty acid (PUFA). The second type was not supplemented and was used for reference. MFO might not be stable during storage and affect negatively the quality of the formula in two ways: by oxidation of PUFA, which may also easily react with lysine upon oxidation, blocking lysine, or by hydrolysis of saccharose, producing reducing sugars and increasing the Maillard reaction. Slight changes were observed in lysine and lactose evolution. By comparing the two formulae, this study shows that the MFO material did not negatively affect the studied parameters, indicating therefore acceptable stability in the conditions tested.
Effect of rhBMP‐2 with PLGA/gelatin sponge type (PGS) carrier on alveolar ridge augmentation in dogs
Authors: KAWAKATSU N. , ODA S. , KINOSHITA A. , KIKUCHI S. , TSUCHIOKA H. , AKIZUKI T. , HAYASHI C. , KOKUBO S. , ISHIKAWA I. , IZUMI Y.
Published: May 2008

Summary  Recombinant human bone morphogenetic protein‐2 has been shown to promote bone formation because of its osteoinductive property. The purpose of this study was to evaluate the efficacy of rhBMP‐2 delivered on a poly (d, l‐lactic‐co‐glycolic acid) copolymer/gelatin sponge (PGS) in vertical alveolar ridge augmentation on height‐reduced edentulous mandible to verify the retention of rhBMP‐2 withstanding the pressure of soft tissues. Coronal defects of the alveolar bone were created in six adult beagle dogs. After a healing period of 9 weeks, PGSs with or without rhBMP‐2 (0 or 0·4 mg mL−1) were implanted on the defects(6 mm in height, 30 mm in length, 8 mm in width). Sixteen weeks after implantation, the bone mineral content (BMC) and the total bone area were measured by peripheral quantitative computed tomography. The BMC and the total bone area of the defect sites with rhBMP‐2 group were significantly greater (133 ± 33 mg mm−1, 277 ± 54 mm2, respectively) than those of the control group (80 ± 19 mg mm−1, 155 ± 49 mm2, respectively) (P < 0·01, P < 0·0001, respectively; paired t‐test). From the histological analyses, the height of newly formed bone in the experimental group was greater than that of the control group (4·3 ± 0·9 mm, 0·22 ± 0·28 mm, P < 0·0001, n = 6, paired t‐test). These results indicate that PGS has characteristics of effective bone graft substitutes for implantation of rhBMP‐2 on vertical alveolar ridge augmentation in huge defect of mandibles in dogs.
Influence of food properties and body posture on durations of swallowing‐related muscle activities
Authors: INAGAKI D. , MIYAOKA Y. , ASHIDA I. , YAMADA Y.
Published: May 2008

Abstract  The purpose of this study was to determine (i) whether or not textural properties of foods and body positions affect the durations of anterior tongue and suprahyoid muscle activities during swallowing, and (ii) if such changes occur, is the ‘pre‐peak’ or the ‘post‐peak’ duration of integrated muscle activity responsible. We used two test foods with different proprieties of hardness and adhesiveness. We recorded electromyograms (EMGs) from the anterior tongue and suprahyoid muscles as well as the laryngeal movement associated with swallowing in normal subjects (six men and three women; 21–30‐years old). The subjects swallowed the test foods in four randomly set postures: upright, two inclined (60 ° and 30 ° to horizontal), and supine. None of the measured durations for the anterior tongue and suprahyoid EMGs were different among the four positions during swallowing of either food. The ‘total’ duration, from the start to the end of the integrated EMG, of anterior tongue activity was significantly (P < 0·001, anova) longer during the swallowing of the tougher and more adhesive food than during swallowing of the other food, but the ‘total’ duration of suprahyoid activity was unchanged. The ‘post‐peak’ duration of anterior tongue activity, which stretched from the peak to the end of the integrated EMG, was also significantly longer (P < 0·001, anova) during swallowing of the tougher and more adhesive food. The results indicate that tougher and more adhesive foods prolong the duration, especially the ‘post‐peak’ duration, of anterior tongue activity during swallowing in the upright, inclined and supine positions.
Three‐dimensional assessment of dental casts’ occlusal surfaces using two impression materials
Authors: TARAWNEH F. M. , PANOS P. G. , ATHANASIOU A. E.
Published: May 2008

Summary  The aim of this study was to assess by means of a three‐dimensional computed tomography scanning system the occlusal surface characteristics of dental casts made using two different impression materials. Alginate and polyvinyl siloxane impressions were taken of 20 dental students resulting in 40 dental casts. The casts were paired for each student separately so that each pair consisted of an alginate poured cast and a polyvinyl siloxane poured out cast. The casts were scanned using FlashCT® scanner and for each cast, a three‐dimensional digital image was obtained. The digitized casts were processed using the three‐dimensional imaging software Geomagic® Studio 9. A total of 464 paired teeth were digitally separated and superimposed. For each tooth, two measurements were obtained corresponding to the two different impression materials used. The two sets of volumes for all digitally separated teeth were compared and analysed using the Wilcoxon signed test. Larger volume measurements were obtained for teeth separated from alginate poured out casts than from their corresponding ones from polyvinyl siloxane casts (P = 0·005). When the teeth were divided into the groups of incisors, canines and premolars/molars, only the last one exhibited significant difference (P = 0·00). The mean difference between the volumes measured for all 464 teeth separated was 0·041 mm3 (±0·33). The occlusal surfaces of teeth appear differently in dental casts depending on the impression materials used. Impressions of dental casts should be utilized with caution in relation to their research application and in reference with dental wear studies.
The generation of nisin variants with enhanced activity against specific Gram‐positive pathogens
Authors: Field Des , Connor Paula M. O. , Cotter Paul D. , Hill Colin , Ross R. Paul
Published: May 2008

Nisin is the prototype of the lantibiotic group of antimicrobial peptides. It exhibits broad spectrum inhibition of Gram‐positive bacteria including important food pathogens and clinically relevant antibiotic‐resistant bacteria. Significantly, the gene‐encoded nature of nisin means that it can be subjected to gene‐based bioengineering to generate novel derivatives. Here, we take advantage of this to generate the largest bank of randomly mutated nisin derivatives reported to date, with the ultimate aim of identifying variants with enhanced bioactivity. This approach led to the identification of a nisin‐producing strain with enhanced bioactivity against the mastitic pathogen Streptococcus agalactiae resulting from an amino acid change in the hinge region of the peptide (K22T). Prompted by this discovery, site‐directed and site‐saturation mutagenesis of the hinge region residues was employed, resulting in the identification of additional derivatives, most notably N20P, M21V and K22S, with enhanced bioactivity and specific activity against Gram‐positive pathogens including Listeria monocytogenes and/or Staphylococcus aureus. The identification of these derivatives represents a major step forward in the bioengineering of nisin, and lantibiotics in general, and confirms that peptide engineering can deliver derivatives with enhanced antimicrobial activity against specific problematic spoilage and pathogenic microbes or against Gram‐positive bacteria in general.
The glutathione‐deficient mutant pad2‐1 accumulates lower amounts of glucosinolates and is more susceptible to the insect herbivore Spodoptera littoralis
Authors: Schlaeppi Klaus , Bodenhausen Natacha , Buchala Antony , Mauch Felix , Reymond Philippe
Published: May 2008

Plants often respond to pathogen or insect attack by inducing the synthesis of toxic compounds such as phytoalexins and glucosinolates (GS). The Arabidopsis mutant pad2‐1 has reduced levels of the phytoalexin camalexin and is known for its increased susceptibility to fungal and bacterial pathogens. We found that pad2‐1 is also more susceptible to the generalist insect Spodoptera littoralis but not to the specialist Pieris brassicae. The PAD2 gene encodes a γ‐glutamylcysteine synthetase that is involved in glutathione (GSH) synthesis, and consequently the pad2‐1 mutant contains about 20% of the GSH found in wild‐type plants. Lower GSH levels of pad2‐1 were correlated with reduced accumulation of the two major indole and aliphatic GSs of Arabidopsis, indolyl‐3‐methyl‐GS and 4‐methylsulfinylbutyl‐GS, in response to insect feeding. This effect was specific to GSH, was not complemented by treatment of pad2‐1 with the strong reducing agent dithiothreitol, and was not observed with the ascorbate‐deficient mutant vtc1‐1. In contrast to the jasmonate‐insensitive mutant coi1‐1, expression of insect‐regulated and GS biosynthesis genes was not affected in pad2‐1. Our data suggest a crucial role for GSH in GS biosynthesis and insect resistance.
Reconstructed interfollicular feline epidermis as a model for the screening of antifungal drugs againstMicrosporum canis
Authors: Tabart Jeremy , Baldo Aline , Vermout Sandy , Losson Bertrand , Mignon Bernard
Published: May 2008

A fully differentiated reconstructed interfollicular feline epidermis (RFE) was recently developedin vitro. It was shown to be relevant for the study ofMicrosporum canis–epidermal interactions. In this study, RFE was evaluated as a potential model for thein vitroscreening of drugs againstM. canis. As a preliminary step, the minimum inhibitory concentration of miconazole nitrate againstM. canisIHEM 21239 grown on Sabouraud's dextrose agar was determined to be 0.3 µg mL−1. RFE grown at the air–liquid interface was cultured for 24 h in RFE culture medium, supplemented with either miconazole (range 0.1–1 µg mL−1) or its solvent (dimethylsulfoxide). Then, RFE was inoculated in triplicate with 1 × 105M. canisarthroconidia and incubated for five additional days. To evaluate fungal growth, RFE was processed for routine histopathology, three serial sections being performed across the block at 100 µm intervals. No fungal growth was detected invading or on the surface of infected RFE in the presence of miconazole concentrations equal to or higher than 0.3 µg mL (final concentration in the culture medium). This study demonstrates that RFE is an adequate model for thein vitroscreening of drugs againstM. canisand potentially against other skin pathogens.
Effects of B‐trichothecenes on luminal glucose transport across the isolated jejunal epithelium of broiler chickens
Authors: Awad W. A. , Razzazi‐Fazeli E. , Böhm J. , Zentek J.
Published: May 2008

Trichothecenes are closely‐related sesquiterpenoids (ring structure) with a 12, 13 epoxy ring and a variable number of hydroxyl, acetyl or other substituents. In chickens, d‐glucose and amino acid absorption occurs via carrier‐mediated transport. Recently, it has been observed that deoxynivalenol (DON) alters the gut function and impairs glucose and amino acid transport in chickens. The purpose of this work was to determine the effects of different B‐trichothecenes [DON, Nivalenol (NIV), 15‐Ac‐DON and Fusarenon X (FUS X)] on intestinal carrier‐mediated sodium co‐transport of d‐glucose in the small intestine of broiler chickens. Intestinal transport was determined by changes in the short‐circuit current (Isc), proportional to ion transmembrane flux, in the middle segment of the jejunum of broilers with the Ussing chamber technique. d‐glucose produced an increase of the Isc, and this effect was reverted by different B‐trichothecene mycotoxins, indicating that the glucose induced Isc was altered by B‐trichothecenes. The addition of glucose after pre‐incubation of the tissues with B‐trichothecenes had no effect (p > 0.05) on the Isc, suggesting that B‐trichothecenes afflicted the Na+‐d‐glucose co‐transport. However, FUX had no obvious effect on the measured parameters. It could be concluded from the present study that the glucose co‐transporter activity appears to be more sensitive to DON, NIV and 15‐Ac‐DON suppression than by FUS X in the jejunum of broilers.