bluuebunny/crossref_metadata_2025 huggingface dataset:
Self‐perceived oral health and salivary proteins in children with type 1 diabetes
Authors: JAVED F. , SUNDIN U. , ALTAMASH M. , KLINGE B. , ENGSTRÖM P‐E.
Published: October 2008

Summary  The aim was to validate self‐perceived oral health with salivary IgG as an inflammatory parameter in children with type 1 diabetes. Unstimulated whole saliva samples were collected from 36 children with well controlled and 12 with poorly controlled type 1 diabetes and 40 non‐diabetic children (Controls). Salivary flow rate, random blood glucose level, salivary protein concentration and immunoglobulin A and G levels were recorded using standard techniques. Data concerning oral health and diabetes status were collected. Self‐perceived gingival bleeding (bleeding gums), bad breath and dry mouth were higher in diabetic children when compared with those in controls (P < 0·05). Gingival bleeding was frequently perceived by children with poorly controlled compared to well‐controlled type 1 diabetes (P < 0·05) and controls (P < 0·001). Bad breath was common perceived by children with poorly controlled compared to well‐controlled type 1 diabetes (P < 0·05) and controls (P < 0·0001). Salivary flow rate was lower in the diabetic children compared to controls (P < 0·01) with no difference between children with poorly controlled and well‐controlled type 1 diabetes. Salivary IgG per mg protein concentration was higher in the diabetics when compared with the control group (P < 0·0001). IgG per mg protein levels were also higher in children with poorly controlled when compared with well‐controlled type 1 diabetes (P < 0·05). There was no difference in IgA per mg protein and total protein concentrations between children with poorly controlled and well‐controlled type 1 diabetes. Self‐perceived gingival bleeding and salivary IgG per mg protein concentration were increased in children with type 1 diabetes compared with controls. These variables were also increased in children with poorly controlled compared with well‐controlled type 1 diabetes.
Specific increase in non‐functional masseter bursts in subjects aware of tooth‐clenching during wakefulness
Authors: KATASE‐AKIYAMA S. , KATO T. , YAMASHITA S. , MASUDA Y. , MORIMOTO T
Published: October 2008

Summary  Previous studies have reported that subjective awareness of a tooth‐clenching habit is associated with increased jaw motor activity (Rao SM, Glaros AG, J Dent Res. 1979;58:1872). The aim of this study was to test the hypothesis that subjects with clenching awareness exhibit different motor expressions specific to non‐functional oromotor activity under laboratory conditions without psychological or sensory effects. Polygraphic and audio–video recordings were made for a 30‐min period of silent reading by 33 subjects without oro‐facial pain. Oro‐facial behaviours (e.g. swallowing, lip movements) were scored according to the polygraphic and audio–video records and masseter bursts were quantitatively analysed. Subjective psychological/sensory measures were also recorded before and/or after the polygraphic recording using a visual analogue scale. The subjects were classified into two groups one with 15 subjects who were aware of having a tooth‐clenching habit and another with 18 who were not aware of any such habit. There were no differences between the groups with respect to the number of functional oro‐facial behaviours or subjective psychological/sensory measures. Masseter bursts unrelated to functional oro‐facial behaviours occurred more frequently in subjects with awareness [median (range) = 23 (2–187) bursts] than in those without [9·0 (0–36); P = 0·01], while neither burst activity [12·3 (1·8–34·5) % of maximum voluntary clenching and 10·1 (6·5–25·1) %, respectively] nor duration [1·17 (0·2–2·2) s and 1·28 (0·3–4·1) s, respectively] differed between the groups. The occurrence of functional oro‐facial behaviours or other body behaviours (e.g. limb and body movements) did not differ between the two groups. These findings suggest that the increased masseter activity in subjects with tooth‐clenching awareness is characterized by a specific increase in non‐functional masseter bursts.
Quality of life in patients with Sjögren’s syndrome and sicca complex
Authors: LÓPEZ‐JORNET P. , CAMACHO‐ALONSO F.
Published: October 2008

Summary  To investigate the general and oral quality of life in patients with Sjögren’s syndrome (SS) and sicca complex. Forty‐four patients with SS were studied consecutively, 33 were primary SS and 11 secondary SS, classified in accordance with the Vitali European criteria. The Spanish version of the Medical Outcome Short Form (36) Health Survey questionnaire (SF‐36) was used to evaluate general quality of life and the Oral Health Impact Profile (OHIP‐49) Spanish version to study oral quality of life. Regarding general quality of life using the SF‐36, when comparing the SS and the control groups, lower scores were obtained in the SS groups in all domains and on comparing primary and secondary SS, lower scores were found for primary SS in all the subscales. With respect to oral quality of life using the OHIP‐49 (all items), we found lower scores for the primary SS group with respect to the control group. Patients with primary SS present lower scores for both oral and general quality of life.
Brain penetration of ivermectin and selamectin inmdr1a,bP‐glycoprotein‐ andbcrp‐ deficient knockout mice
Authors: GEYER J. , GAVRILOVA O. , PETZINGER E.
Published: October 2008

P‐glycoprotein, which is encoded by the multi‐drug resistance gene (MDR1), highly restricts the entry of ivermectin into the brain by an ATP‐driven efflux mechanism at the blood–brain barrier. In dogs with a homozygous MDR1 mutation though, ivermectin accumulates in the brain and provokes severe signs of neurotoxicosis and even death. In contrast to ivermectin, selamectin is safer in the treatment of MDR1 mutant dogs, suggesting that selamectin is transported differently by P‐glycoprotein across the blood–brain barrier. To test this, we applied selamectin to mdr1‐deficientmdr1a,b−/−knockout mice and wild‐type mice. Brain penetration, organ distribution, and plasma kinetics were analyzed after intravenous, oral, and dermal spot‐on application in comparison with ivermectin. We found thatin vivoboth macrocyclic lactone compounds are substrates of P‐glycoprotein and that these strongly accumulate in the brain ofmdr1a,b−/−knockout mice compared with wild‐type mice at therapeutic doses of 12 mg/kg selamectin and 0.2 mg/kg ivermectin. However, selamectin accumulates to a much lesser degree (5–10 times) than ivermectin (36–60 times) in the absence of P‐glycoprotein. This could explain the broader margin of safety of selamectin in MDR1 mutant dogs. In liver, kidney, and testes, ivermectin and selamectin accumulated less than four times as much inmdr1a,bmutant mice as in wild‐type mice. Breast cancer resistance protein (Bcrp)‐deficientbcrp−/−knockout mice were also included in the application studies, but showed no differences in brain concentrations or organ distribution of either ivermectin or selamectin compared with wild‐type mice. This indicates that Bcrp is not a relevant efflux carrier for these macrocyclic lactone compoundsin vivoat the blood–brain barrier.
Sinorhizobium meliloti, a bacterium lacking the autoinducer‐2 (AI‐2) synthase, responds to AI‐2 supplied by other bacteria
Authors: Pereira Catarina S. , McAuley J. Randall , Taga Michiko E. , Xavier Karina B. , Miller Stephen T.
Published: October 2008

Many bacterial species respond to the quorum‐sensing signal autoinducer‐2 (AI‐2) by regulating different niche‐specific genes. Here, we show that Sinorhizobium meliloti, a plant symbiont lacking the gene for the AI‐2 synthase, while not capable of producing AI‐2 can nonetheless respond to AI‐2 produced by other species. We demonstrate that S. meliloti has a periplasmic binding protein that binds AI‐2. The crystal structure of this protein (here named SmlsrB) with its ligand reveals that it binds (2R,4S)‐2‐methyl‐2,3,3,4‐tetrahydroxytetrahydrofuran (R‐THMF), the identical AI‐2 isomer recognized by LsrB of Salmonella typhimurium. The gene encoding SmlsrB is in an operon with orthologues of the lsr genes required for AI‐2 internalization in enteric bacteria. Accordingly, S. meliloti internalizes exogenous AI‐2, and mutants in this operon are defective in AI‐2 internalization. S. meliloti does not gain a metabolic benefit from internalizing AI‐2, suggesting that AI‐2 functions as a signal in S. meliloti. Furthermore, S. meliloti can completely eliminate the AI‐2 secreted by Erwinia carotovora, a plant pathogen shown to use AI‐2 to regulate virulence. Our findings suggest that S. meliloti is capable of ‘eavesdropping’ on the AI‐2 signalling of other species and interfering with AI‐2‐regulated behaviours such as virulence.
Uptake of the antifungal cationic peptide Histatin 5 by Candida albicans Ssa2p requires binding to non‐conventional sites within the ATPase domain
Authors: Sun Jianing N. , Li Wansheng , Jang Woong Sik , Nayyar Namrata , Sutton Mark D. , Edgerton Mira
Published: October 2008

Candida albicans Hsp70 Ssa1/2 proteins have been identified as cell wall binding partners for the antifungal cationic peptide Histatin 5 (Hst 5) in vivo. C. albicans Ssa2p plays a major role in binding and translocation of Hst 5 into fungal cells, as demonstrated by defective peptide uptake and killing in C. albicans SSA2 null mutants. Candidal Hsp70 proteins are classical chaperone proteins with two discrete functional domains consisting of peptide binding and ATP binding regions. Pull‐down assays with full‐length and truncated Ssa2 proteins found that the ATPase domain was required for Hst 5 binding. Further mapping of Ssa2p by limited digestion and peptide array analyses identified two discrete Hst 5‐binding epitopes within the ATPase region. Expression of Ssa2p in C. albicans cells carrying mutations in the first epitope identified by thermolysin digestion (Ssa2128−132A3) significantly reduced intracellular transport and fungicidal activity of Hst 5, confirming its importance as a binding site for Hst 5 function in vivo. Since this Hst 5 binding site lies within the Ssa2p ATPase domain near the ATP‐binding cleft, it is possible that ATP modulates Hst 5 binding to Ssa2p. Indeed, gel filtration assays demonstrated that although nucleotides are not required for Hst 5 binding, their presence improved binding affinity by 10‐fold. Thus, C. albicans Ssa2p binds Hst 5 at a surface‐localized epitope in a subunit of the ATPase domain; and this region is required for intracellular translocation and killing functions of Hst 5.
Ribosome biogenesis; the KsgA protein throws a methyl‐mediated switch in ribosome assembly
Authors: Mangat Chand S. , Brown Eric D.
Published: October 2008

Many trans‐acting factors that aid in ribosome biogenesis have been identified in higher organisms but relatively few such factors are known in prokaryotes. In bacteria, the list of such factors includes ATP‐energized helicases and chaperones as well as an emerging cadre of switch GTPases. The KsgA protein is a universally conserved methyltransferase that dimethylates both A1518 and A1519 of the 16S rRNA of the small ribosomal subunit. Methylation has long been thought to be solely for fine‐tuning of protein translation. In this issue of Molecular Microbiology, Connolly et al. present data suggesting KsgA might function in the assembly of the small subunit of the ribosome. Indeed, the work indicates that KsgA might have a checkpoint role in ribosome biogenesis where methylation by this protein marks the completion of its assembly role. These findings open our thinking to new candidate assembly factors and provide a new direction for understanding ribosome assembly.
Identification of VceA and VceC, two members of the VjbR regulon that are translocated into macrophages by the Brucella type IV secretion system
Authors: De Jong Maarten F. , Sun Yao‐Hui , Den Hartigh Andreas B. , Van Dijl Jan Maarten , Tsolis Renée M.
Published: October 2008

Survival and replication inside host cells by Brucella spp. requires a type IV secretion system (T4SS), encoded by the virB locus. However, the identity of the molecules secreted by the T4SS has remained elusive. We hypothesized that proteins translocated by the T4SS would be co‐regulated with the virB operon. The LuxR family regulator VjbR, known to regulate virB, bound a fragment of the virB promoter containing an 18 bp palindromic motif (virB promoter box), showing that VjbR regulated the virB operon directly. To identify virB co‐regulated genes, we searched the Brucella suis 1330 and B. abortus 2308 genomes for genes with an upstream virB promoter box. One hundred and forty‐four promoters in the two genomes contained the virB promoter box, including those of fliC encoding flagellin and cgs encoding cyclic β‐glucan synthetase. Thirteen of these proteins were tested for VirB‐dependent translocation into macrophages using a β‐lactamase reporter assay. This analysis resulted in the identification of the proteins encoded by BAB1_1652 (VceA) and BR1038/BAB1_1058 (VceC) as novel protein substrates of the Brucella T4SS. VceC could also be translocated by the Legionella pneumophila Dot/Icm T4SS into host cells. Our results suggest that VjbR co‐ordinates expression of the T4SS and at least two of its secreted substrates.
Abrogation of ospAB constitutively activates the Rrp2‐RpoN‐RpoS pathway (sigmaN‐sigmaS cascade) in Borrelia burgdorferi
Authors: He Ming , Oman Tara , Xu Haijun , Blevins Jon , Norgard Michael V. , Yang X. Frank
Published: October 2008

Molecular mechanisms underlying the reciprocal regulation of the two major surface lipoproteins and virulence factors of Borrelia burgdorferi, OspA and OspC, are not fully understood. Herein, we report that inactivation of the ospAB operon resulted in overproduction of OspC and many other lipoproteins via the constitutive activation of the Rrp2‐RpoN‐RpoS pathway. Complementing the ospAB mutant with a wild‐type copy of ospA, but not an ospA variant that lacks the lipoprotein signal sequence, restored normal regulation of the Rrp2‐RpoN‐RpoS pathway; these results indicate that the phenotype was not caused by spurious mutations. Interestingly, while most of the ospAB mutant clones displayed a constitutive ospC expression phenotype, some ospAB mutant clones showed little or no ospC expression. Further analyses revealed that this OspC‐negative phenotype was independent of abrogation of ospAB. While activation of the Rrp2‐RpoN‐RpoS pathway was recently shown to downregulate ospA, our findings suggest that reduction of OspA can also activate this pathway. We postulate that the activation of the Rrp2‐RpoN‐RpoS pathway and downregulation of OspA form a positive feedback loop that allows spirochaetes to produce and maintain a constant high level of OspC and other lipoproteins during tick feeding, a strategy that is critical for spirochaetal transmission and mammalian infection.
Vesicle amine transport protein‐1 (VAT‐1) is upregulated in glioblastomas and promotes migration
Authors: Mertsch S. , Becker M. , Lichota A. , Paulus W. , Senner V.
Published: October 2008

Aim: Diffuse invasion of single‐glioma cells is the main obstacle to successful therapy of these tumours. After identifying vesicle amine transport protein‐1 (VAT‐1) as being upregulated in invasive human gliomas, we study its possible function in glioblastoma cell migration. Methods: Based on data obtained from previous oligonucleotide arrays, we investigated expression of VAT‐1 in glioblastoma tissue and cell lines on mRNA levels using reverse transcriptase PCR. Furthermore, we examined the amount and localization of VAT‐1 protein using immunoblotting and immunohistochemistry. Using small interfering RNA technology we repressed VAT‐1 expression in human glioma cell lines and analysed their migration using wound healing and transwell migration assays. Results: Increased VAT‐1 mRNA and protein levels were found in glioblastoma tissues and cell lines compared with normal human brain. Small interfering RNA‐mediated VAT‐1 knockdown led to significantly reduced migration of human glioma cells. Conclusions: VAT‐1 is overexpressed in glioblastomas and functionally involved in glioma cell migration, representing a new component involved in glioma invasion.
Effect of Nippostrongylus brasiliensis L3 ES on inflammatory mediator gene transcription in lipopolysaccharide lung inflammation
Authors: ZHAO M. , BROWN D. M. , MACCALLUM J. , PROUDFOOT L.
Published: October 2008

The anti‐inflammatory properties of parasitic helminths have been largely linked to their excretory–secretory (ES) products. Some studies have noted a lack of TNF‐α production and limited recruitment of neutrophils into the lungs after Nippostrongylus brasiliensis infection. We previously reported that instillation of ES from L3 larvae of N. brasiliensis to the lungs could inhibit the recruitment of neutrophils on a background of LPS‐induced inflammation. A similar reduction in neutrophil recruitment was observed in this study. This reduction was associated with the significant inhibition in gene transcription of the adhesion molecule, ICAM‐1, and the chemokine, MIP‐2 in bronchoalveolar lavage (BAL) cells. The LPS‐stimulated gene transcription of the pro‐inflammatory cytokines TNF‐α and IL‐1β was also significantly reduced by L3 ES. Inducible nitric oxide synthase (iNOS) is normally elevated in classically activated macrophages, however, in this case gene transcription of iNOS was inhibited by L3 ES and may suggest a phenotype change to anti‐inflammatory. The general inhibition of pro‐inflammatory mediators observed in this study suggests that infective stage L3 larvae excrete and/or secrete inhibitory products capable of modifying the normally potent LPS inflammatory response.
Comparison of four statistical approaches to score child development: a study of Malawian children
Authors: Cheung Yin‐Bun , Gladstone Melissa , Maleta Ken , Duan Xiaolian , Ashorn Per
Published: October 2008

Objective  Assessment of child development often results in a multitude of binary outcome data. There is no agreed way to use them to score the developmental status of children. Conventional methods include age‐standardized Z‐scores and simple sum of number of passes. Recently two approaches based on the Rasch model and the concept of ‘developmental age’ have been proposed. This study aims to compare the performance of the four approaches.

Methods  In a longitudinal study, 473 Malawian children were measured for growth status at age 36 months and administered a new test of developmental milestones between age 3 and 6 years. The test consisted of four domains: gross motor (GM), fine motor (FM), social and language development. The four approaches were used to score the developmental level of each child in each domain, and the results compared.

Results  In this sample, the approach based on the Rasch model provided development scores that were more normally distributed than the other approaches did. The four sets of scores were highly correlated with each other. They gave similar estimates of the effect of height‐for‐age on GM, social and language development. In FM development, the maximum difference in the effect size estimates was only 0.04 standard deviation despite its statistical significance (P = 0.009).

Conclusion  The four approaches were practically equivalent in the context of the estimation of an intervention effect or association. Their relative advantages and disadvantages are discussed. None of them can be universally recommended.
What does dengue disease surveillance contribute to predicting and detecting outbreaks and describing trends?
Authors: Runge‐Ranzinger Silvia , Horstick Olaf , Marx Michael , Kroeger Axel
Published: October 2008

Objective To review the evidence on the application of tools for dengue outbreak prediction/detection and trend monitoring in passive and active disease surveillance systems in order to develop recommendations for endemic countries and identify research needs.

Method Systematic review of literature in the Cochrane Database of Systematic Reviews, PubMed, EMBASE, Lilacs, WHO library database, manual reference search and grey literature. Two reviewers independently applied pre‐defined inclusion and exclusion criteria and assessed the level of evidence. Studies describing the outcome of dengue disease surveillance with respect to trend monitoring and outbreak prediction/detection based on empirical data were included.

Results Twenty‐four studies (of 1804 references) met the eligibility criteria. Different indicators and their respective threshold values were identified as potential triggers for outbreak alerts through retrospective analysis of data from passive and/or active surveillance systems. Some indicators are potentially useful for predicting imminent outbreaks in the low transmission season and others for detecting outbreaks at an early stage. However, the information collected is mainly retrospective and often site‐specific and appropriate levels of sensitivity and specificity of the outbreak indicators/triggers could not be determined. Retrospective and prospective virus surveillance studies were not conclusive regarding the question of whether a newly introduced serotype is an outbreak predictor, but contributed additional indicators for outbreak prediction/detection. Under‐reporting was a major concern. Taking cost and feasibility issues into account, it remains an open question whether dengue surveillance should be passive (based on routine reporting) or active (based on more costly sentinel or other active population based surveillance systems). Adding active surveillance elements to a well‐functioning passive surveillance system improves sensitivity; adding laboratory elements to the system improves specificity.

Conclusions In view of the lack of evidence about the most feasible and sustainable surveillance system in a country context, countries could use a stepwise approach to locally adapt their passive routine surveillance system into an improved combined active/passive surveillance approach. Prospective studies are needed to better define the most appropriate dengue surveillance system and trigger for dengue emergency response.
Canine mast cell tumours: a review of the pathogenesis, clinical features, pathology and treatment
Authors: Welle Monika M. , Bley Carla Rohrer , Howard Judith , Rüfenacht Silvia
Published: October 2008

Mast cells (MCs) are well known for their neoplastic transformation in solitary and multiple cutaneous mast cell tumours (MCTs), as well as visceral and systemic mastocytosis. Dogs have a unique risk of developing cutaneous MCTs, and they account for 7% to 21% of all canine skin tumours. The aetiology of canine MCTs is unknown but is probably multifactorial. This article reviews up‐to‐date knowledge on the pathogenesis, the clinical presentation, the clinical prognostic factors, the diagnostic workup including clinical staging, cytological findings, histological findings and the various grading systems which have been evaluated based on morphology, the assessment of proliferation markers and other factors such as vessel density. Furthermore, detailed information about current treatment protocols for canine cutaneous MCTs is provided.
Nicotine self‐medication of cognitive‐attentional processing
Authors: Evans David E. , Drobes David J.
Published: October 2008

This article selectively reviews research concerning nicotine's effects on cognition, including the neurobiological mechanism for these effects, task and experimental features that may be important for elucidating these effects, and why these effects may have amplified motivational significance among smokers with cognitive deficit. Nicotine has effects on various cognitive processes, though most studies in humans have focused on the amelioration of cognitive deficits experienced during drug withdrawal. The direct cognitive‐enhancing effect of nicotine remains a controversial topic. The relationship between attentional and non‐attentional cognitive effects of nicotine is discussed in the context of cognitive self‐medication. Further research should include theory‐driven examination of cognitive effects of nicotine, and develop targeted smoking cessation programs based on an improved understanding of the role of cognitive self‐medication in high‐risk individuals.
Stress, alcohol and drug interaction: an update of human research
Authors: Uhart Magdalena , Wand Gary S.
Published: October 2008

A challenging question that continues unanswered in the field of addiction is why some individuals are more vulnerable to substance use disorders than others. Numerous risk factors for alcohol and other drugs of abuse, including exposure to various forms of stress, have been identified in clinical studies. However, the neurobiological mechanisms that underlie this relationship remain unclear. Critical neurotransmitters, hormones and neurobiological sites have been recognized, which may provide the substrates that convey individual differences in vulnerability to addiction. With the advent of more sophisticated measures of brain function in humans, such as functional imaging technology, the mechanisms and neural pathways involved in the interactions between drugs of abuse, the mesocorticolimbic dopamine system and stress systems are beginning to be characterized.

This review provides a neuroadaptive perspective regarding the role of the hormonal and brain stress systems in drug addiction with a focus on the changes that occur during the transition from occasional drug use to drug dependence. We also review factors that contribute to different levels of hormonal/brain stress activation, which has implications for understanding individual vulnerability to drug dependence. Ultimately, these efforts may improve our chances of designing treatment strategies that target addiction at the core of the disorder.
Developing human laboratory models of smoking lapse behavior for medication screening
Authors: McKee Sherry A.
Published: October 2008

Use of human laboratory analogues of smoking behavior can provide an efficient, cost‐effective mechanistic evaluation of a medication signal on smoking behavior, with the result of facilitating translational work in medications development. Although a number of human laboratory models exist to investigate various aspects of smoking behavior and nicotine dependence phenomena, none have yet modeled smoking lapse behavior. The first instance of smoking during a quit attempt (i.e. smoking lapse) is highly predictive of relapse and represents an important target for medications development. Focusing on an abstinence outcome is critical for medication screening as the US Food and Drug Administration approval for cessation medications is contingent on demonstrating effects on smoking abstinence. This paper outlines a three‐stage process for the development of a smoking lapse model for the purpose of medication screening. The smoking lapse paradigm models two critical features of lapse behavior: the ability to resist the first cigarette and subsequent ad libitum smoking. Within the context of the model, smokers are first exposed to known precipitants of smoking relapse (e.g. nicotine deprivation, alcohol, stress), and then presented their preferred brand of cigarettes. Their ability to resist smoking is then modeled and once smokers ‘give in’ and decide to smoke, they participate in a tobacco self‐administration session. Ongoing and completed work developing and validating these models for the purpose of medication screening is discussed.
The interaction between early life upper respiratory tract infection and birth during the pollen season on rye‐sensitized hay fever and ryegrass sensitization – a birth cohort study
Authors: Kemp Andrew , Ponsonby Anne‐Louise , Dwyer Terry , Cochrane Jennifer , Pezic Angela , Carmichael Alan , Carlin John , Jones Graeme
Published: October 2008

Studies on early life viral respiratory infection and subsequent atopic disease in childhood have conflicting findings. Animal models show that viral respiratory infection in conjunction with allergen presentation can enhance sensitization. This prospective study assesses the influence of an upper respiratory tract infection (URI) in the first month of life and the season of birth on the development of hay fever and ryegrass allergen sensitization in childhood. From a Tasmanian cohort born during 1988 and 1989, a group of 498 children were followed up at 8 yr and another different group of 415 children were followed up at 16 yr. The ryegrass pollen season in Tasmania occurs in November and December. Forty‐four (9.6%) children in Follow‐up sample 1 and 47 (12.5%) children in Follow‐up sample 2 were born in the pollen season. The parental report of an early upper respiratory tract infection (EURI) was documented prospectively by a home interview at 1 month of age (median age 5.1 wk). Sensitization to ryegrass and house dust mite (HDM) was determined at 8 yr of age by skin prick testing and at 16 yr by ImmunoCap®. Ryegrass sensitized hay fever was defined as a positive response to a question on hay fever plus the presence of ryegrass allergy. For children tested at age 8 and born in the pollen season, a EURI by postnatal interview was associated with an increased risk of ryegrass sensitization (OR 5.80 95% CI 1.07, 31.31) but not for children with a EURI born outside the pollen season (OR 0.62 95% CI 0.35, 1.08). Similarly, EURI was significantly associated with early onset (≤8 yr) ryegrass sensitized hay fever for children born in the pollen season (AOR 4.78 95% CI 1.17, 19.47) but was not associated with early onset ryegrass sensitized hay fever for children born outside the pollen season (AOR 0.76 95% CI 0.43, 1.33). These findings suggest that early life viral URI interacts with ryegrass allergen exposure in the development of ryegrass allergen sensitization and ryegrass sensitized hay fever symptoms.
Though with constraints imposed by endosymbiosis, preferential attachment is still a plausible mechanism responsible for the evolution of the chloroplast metabolic network
Authors: WANG Z. , ZHU X.‐G. , CHANG X. , CHEN Y. Z. , LI Y. X. , LIU L.
Published: October 2008

Chloroplasts evolved as a result of endosymbiosis, during which sophisticated mechanisms evolved to translocate nucleus‐encoded plastid‐targeted enzymes into the chloroplast to form the chloroplast metabolic network. Given the constraints and complexity of endosymbiosis, will preferential attachment still be a plausible mechanism for chloroplast metabolic network evolution? We answer this question by analysing the metabolic network properties of the chloroplast and a cyanobacterium, Synechococcus sp. WH8102 (syw). First, we found that enzymes related to more ancient pathways are more connected, and synthetases have the highest connectivity. Most of the enzymes shared by the two densest cores between the chloroplast and syw are synthetases. Second, the highly conserved functional modules mainly consist of highly connected enzymes. Finally, isozymes and enzymes from endosymbiotic gene transfer (EGT) were distributed mainly in conserved modules and showed higher connectivity than nonisozymes or non‐EGT enzymes. These results suggest that even with severe evolutionary constraints imposed by endosymbiosis, preferential attachment is still a plausible mechanism responsible for the evolution of the chloroplast metabolic network. However, the current analysis may not completely differentiate whether the chloroplast network properties reflect the evolution of the chloroplast network through preferential attachment or has been inherited from its cyanobacterial ancestor. To fully differentiate these two possibilities, further analyses of the metabolic network structure properties of organisms at various intermediate evolutionary stages between cyanobacteria and the chloroplast are needed.
Overdominant maintenance of diversity in the sea star Pisaster ochraceus
Authors: PANKEY M. S. , WARES J. P.
Published: October 2008

When individuals have higher evolutionary fitness because of being heterozygous at a given gene region, it is known as overdominance. Although overdominant selection could represent an important mechanism for maintaining genetic variation within species, the prevalence of this mode of selection appears to be relatively low. Identification of cases of true single‐locus heterozygote advantage are thus useful reference points in our overall understanding of how various forms of balancing selection influence and maintain genetic variation in natural populations. Here we report the apparent long‐term maintenance of diversity via overdominant selection with homozygous lethality at an elongation factor locus in the sea star Pisaster ochraceus. Observing this pattern in a gene with such major effects on protein assembly indicates that overdominant selection could be a more prevalent factor in maintaining allelic diversity in the wild than previously recognized.
What do human economies, large islands and forest fragments reveal about the factors limiting ecosystem evolution?
Authors: LEIGH, JR E. G. , VERMEIJ G. J. , WIKELSKI M.
Published: October 2008

What factors limit ecosystem evolution? Like human economies, ecosystems are arenas where agents compete for locally limiting resources. Like economies, but unlike genes, ecosystems are not units of selection. In both economies and ecosystems, productivity, diversity of occupations or species and intensity of competition presuppose interdependence among many different agents. In both, competitive dominants need abundant, varied resources, and many agents’ products or services, to support the activity and responsiveness needed to maintain dominance. Comparing different‐sized land masses suggests that productivity is lower on islands whose area is too small to maintain some of the interdependences that maintain diversity, productivity and competitiveness in mainland ecosystems. Islands lacking the rare, metabolically active dominants that make competition so intense in mainland ecosystems are more easily invaded by introduced exotics. Studies of islets in reservoirs identify mechanisms generating these phenomena. These phenomena suggest how continued fragmentation will affect future ‘natural’ ecosystems.
Non‐gelatinized starch influences the deposition of n‐3 fatty acids in the muscle of a tropical freshwater fish, Labeo rohita
Authors: Kumar V. , Sahu N. P. , Pal A. K. , Kumar S. , Sharma P. , Chettri J. K. , Sinha A. K.
Published: October 2008

A 60‐day feeding trial was conducted to study the influence of gelatinized (G) to non‐gelatinized (NG) starch ratio in the diet on fatty acids profiles and oxidative status in Labeo rohita fingerlings. Two hundred and thirty‐four fingerlings (average weight: 2.53 g) were distributed in six treatment groups with each of three replicates. Six semi‐purified diets either containing NG and/or G corn starch (42.43%) viz., T1 (100% NG and 0% G starch), T2 (80% NG and 20% G starch), T3 (60% NG and 40% G starch), T4 (40% NG and 60% G starch), T5 (20% NG and 80% G starch) and T6 (0% NG and 100% G starch) was fed to respective groups. Catalase, superoxide dismutase and malic enzyme activities decreased linearly with the increasing level of G starch, whereas reverse trend was found for glucose‐6‐phosphate dehydrogenase. Total saturated fatty acids in muscle increased with the increasing level of G starch in the diet. Total n‐3 fatty acids decreased linearly with the increasing level of G starch in the diet. Among the n‐3 fatty acids, linolenic acids content was more in NG starch fed group. Similarly, eicosapentaenoic acid contents gradually decreased with increasing level of G starch content. The n‐6/n‐3 ratio was higher in G starch fed group. This suggests that dietary starch type may be manipulated for quality improvement of fish flesh.
Identification of Three Strains of a Virus Associated with Cassava Plants Affected by Frogskin Disease
Authors: Calvert L. A. , Cuervo M. , Lozano I. , Villareal N. , Arroyave J.
Published: October 2008

Cassava Frogskin Disease (CFSD) can cause severe damage to cassava roots and is one of the most important diseases of cassava in Latin America. The principal objective of this study was to identify the causal agent of CFSD. Electron microscopy, viral purifications, double‐stranded RNA (dsRNA) analysis, cloning, sequencing, rtPCR and hybridizations were carried out to characterize and associate a novel virus with the disease. Virus‐like particles of 70 and 45 nm in diameter were found in affected cassava plants and partially purified preparations respectively. Nine species of dsRNA were associated with this disease and cDNA clones to six genomic segments were synthesized from the purified dsRNAs. The putative proteins predicted from the sequence of the cassava virus cDNA clones have similarity with the P1, P2, P3, P4, P5 and P10 proteins of Rice ragged stunt virus (RRSV). Phylogenic analysis confirmed that this virus is a member of the family Reoviridae and is most closed related to RRSV. Hybridization analyses of dsRNA identified S1, S2, S3, S4, S5 and S10 genomic segments in the CFSD‐affected plants, but not in healthy controls. Additionally, 26 isolates were compared using a portion of the putative polymerase gene. The virus was detected in all 26 isolates, and they were classified into three distinct races. The association of this virus with CFSD was strengthened by the detection of this virus in diseased plants collected from different locations throughout Colombia.
Deep‐sea reef fish assemblage patterns on the Blake Plateau(Western North Atlantic Ocean)
Authors: Ross Steve W. , Quattrini Andrea M.
Published: October 2008

Deep‐water coral habitats are scattered throughout slope depths (360–800 m) off the Southeastern United States (SEUS, Cape Lookout, North Carolina, to Cape Canaveral, Florida), contributing substantial structure and diversity to bottom habitats. In some areas (e.g. off North Carolina) deep corals form nearly monotypic (Lophelia pertusa) high profile mounds, and in other areas (e.g. off Florida) many species may colonize hard substrata. Deep coral and hard substrata ecosystems off the SEUS support a unique fish assemblage. Using the Johnson‐Sea‐Link submersible (in 2000–2005, 65 dives), and a remotely operated vehicle (in 2003, five dives), fishes were surveyed in nine deep reef study areas along the SEUS slope. Forty‐two benthic reef fish species occurred in deep reef habitats in these study areas. Species richness was greatest on the two coral banks off Cape Lookout, North Carolina (n = 23 and 27 species) and lowest on the two sites off Cape Canaveral, Florida (n = 7 and 8 species). Fish assemblages exhibited significantly (ANOSIM, Global R = 0.69, P = 0.001) different patterns among sites. Stations sampled off North Carolina (three study areas) formed a distinct group that differed from all dives conducted to the south. Although several species defined the fish assemblages at the North Carolina sites, Laemonema barbatulum, Laemonema melanurum, and Helicolenus dactylopterus generally had the most influence on the definition of the North Carolina group. Fish assemblages at three sites within the central survey area on the Blake Plateau were also similar to each other, and were dominated by Nezumia sclerorhynchus and L. melanurum. Synaphobranchus spp. and Neaumia sclerorhynchus differentiated the two southern sites off Cape Canaveral, Florida, from the other station groups. Combinations of depth and habitat type had the most influence on these station groups; however, explicit mechanisms contributing to the organization of these assemblages remain unclear.
Factors Affecting the Quality of Cryopreserved Buffalo (Bubalus bubalis) Bull Spermatozoa
Authors: Andrabi SMH
Published: October 2008

Contents

Storage of buffalo (Bubalus bubalis) bull semen in the cryopreserved state is discussed in this article. Fertility rate in buffalo following artificial insemination with frozen–thawed semen is reviewed. To better understand the freezability of bubaline spermatozoa, the available data on biochemical components and the activity of specific enzymes of semen/spermatozoa are given. Moreover, the major factors that may influence the post‐thaw viability and fertility of buffalo spermatozoa are examined in detail. In addition, suggestions for improvement in cryogenic procedures for buffalo spermatozoa are also given.
EFFECT OF THE PHOSPHODIESTERASE 5 INHIBITORS SILDENAFIL, TADALAFIL AND VARDENAFIL ON RAT ANOCOCCYGEUS MUSCLE: FUNCTIONAL AND BIOCHEMICAL ASPECTS
Authors: Toque Haroldo A , Priviero Fernanda BM , Zemse Saiprasad M , Antunes Edson , Teixeira Cleber E , Webb R Clinton
Published: October 2008

The anococcygeus muscle is part of the erectile machinery in male rodents. Phosphodiesterase (PDE) 5 inhibitors enhance and prolong the effects of cGMP, which has a key role in penile erection. The aim of the present study was to provide a functional and biochemical comparison of the three PDE5 inhibitors, namely sildenafil, tadalafil and vardenafil, in the rat anococcygeus muscle.

Muscle strips were mounted in 4 mL organ baths and isometric force recorded. Levels of cGMP were measured using an enzyme immunoassay kit. Western blots were used to determine PDE5 protein expression.

The PDE5 inhibitors concentration‐dependently relaxed carbachol‐precontracted anococcygeus muscle; however, vardenafil was more potent (pEC50 = 8.11 ± 0.05) than sildenafil (7.72 ± 0.06) or tadalafil (7.69 ± 0.05). Addition ofNG‐nitro‐l‐arginine methyl ester (100 µmol/L) or 1H‐[1,2,4]oxadiazolo[4,3‐a]quinoxalin‐1‐one (10 µmol/L) to the organ baths caused significant rightward shifts in concentration–response curves for all PDE5 inhibitors.

Sildenafil, tadalafil and vardenafil (all at 0.1 µmol/L) caused leftward shifts in the glyceryl trinitrate (GTN) concentration‐response curves (by 4.0‐, 3.7‐ and 5.5‐fold, respectively). In addition, all three PDE5 inhibitors significantly potentiated relaxation responses to both GTN (0.01–10 µmol/L) and electrical field stimulation (EFS; 1–32 Hz), with vardenafil having more pronounced effects.

All three PDE5 inhibitors reduced EFS‐evoked contractions in a concentration‐dependent manner over the concentration range 0.001–1 µmol/L. There were no significant differences between the effects of the three PDE5 inhibitors.

Vardenafil (0.01–0.1 µmol/L) was more potent in preventing cGMP degradationin vitrothan sildenafil (0.01–0.1 µmol/L) and tadalafil (0.01–0.1 µmol/L).

Under control conditions, the expression of PDE5 was higher in the anococcygeus muscle than in the corpus cavernosum.

In conclusion, PDE5 inhibitors enhance exogenous and endogenous nitric oxide‐mediated relaxation in the rat anococcygeus muscle. The potency of vardenafil was greater than that of either sildenafil or tadalafil.
MELATONIN PROTECTS AGAINST HYDROGEN PEROXIDE‐INDUCED GASTRIC INJURY IN RATS
Authors: Mohamadin Ahmed M , Ashour Osama M , El‐Sherbeny Nagla A , Alahdal Abdulrahman M , Morsy Gehan M , Abdel‐Naim Ashraf B
Published: October 2008

Melatonin (MT) is a pineal hormone that is also abundant in the gut and has a well known role in scavenging oxygen free radicals. The aim of the present study was to evaluate the potential protective effects of MT against H2O2‐induced gastric lesions in rats.

An experimental model of gastric ulceration was established in rats using 15% H2O2. Melatonin (12.5, 25 or 50 mg/kg, intagastrically) was administered to rats 30 min before H2O2challenge.

Intragastric administration of H2O2resulted in haemorrhagic lesions in the fundic area of the stomach. Furthermore, H2O2induced gastric oxidative stress, as indicated by depletion of reduced glutathione (GSH), inhibition of glutathione peroxidase (GPx) activity and elevation of malonedialdehyde (MDA) levels. These effects were accompanied by decreased gastric tissue levels of prostaglandin (PG) E2and nitric oxide (NO), as well as increased levels of tumour necrosis factor (TNF)‐α. Administration of MT (12.5, 25 or 50 mg/kg) 30 min before H2O2significantly attenuated the development of gastric lesions in a dose‐dependent manner. The protective effects of MT were accompanied by significant inhibition of the H2O2‐induced reduction in gastric content of GSH and GPx activity and elevation in MDA levels. Furthermore, MT antagonized H2O2‐induced reduction of gastric PGE2and NO levels and elevation of TNF‐α.

In conclusion, MT protects rat gastric mucosa against H2O2‐induced damage. The observed protective effects of MT can be attributed, at least in part, to its anti‐oxidant properties, preservation of PGE2and NO levels, as well as inhibition of TNF‐α induction in gastric tissues.
Crack length and stable crack extension measurements from images acquired by means of a conventional flatbed scanner
Authors: KORIN I. , LARRAINZAR C. , IPIÑA J. PEREZ
Published: October 2008

The crack length measurements of both the original crack length and the stable crack extension are requested by several fracture toughness test methods, wherein which high accuracy measurement instruments are demanded. Low magnification optical microscopes as well as travelling‐stage microscopes are used to achieve the accuracy requirements, although many times these time‐consuming techniques present some experimental difficulties, especially when a great number of specimens have to be measured. A methodology to measure crack length from high‐resolution images acquired by means of a desktop flatbed‐scanner is presented in this paper. The acquired images are analysed by means of software that allows obtaining the crack length. Several aspects were studied to demonstrate the suitability of the method: the optical resolution, the depth of field and the effects of possible optical aberrations. Finally, an uncertainty balance was performed to demonstrate that the methodology is able to reach the necessary accuracy required by the fracture toughness test methods.
The effects of 45 degree head up tilt on the lumbar puncture success rate in children undergoing spinal anesthesia
Authors: APILIOGULLARI SEZA , DUMAN ATES , GOK FUNDA , OGUN CEMILE OZTIN , AKILLIOGLU ISHAK
Published: October 2008

Background:  There are few studies for procedural techniques of lumbar puncture (LP) for spinal anesthesia in children. There are no controlled studies on the effect of patient positioning. We designed this prospective, randomized study to compare the success rates of LP of the lateral decubitus and lateral decubitus position with a 45 degree head up tilt in children undergoing spinal anesthesia.

Methods:  Study was conducted in 180 children aged between one month to twelve years. The LP was performed under general anesthesia using sevoflurane with a 26‐gauge, atraumatic needle either in the standard lateral decubitus, knee‐chest position (group I, n = 90) or lateral decubitus, knee‐chest position with a 45 degree head up tilt (group II, n = 90). The free flow of clear cerebrospinal fluid (CSF) at first attempt was considered to evidence a successful LP.

Results:  The two groups were similar in age and weight. Total LP success rate was higher in group II than in group I (P < 0.05). When the significance between the groups was evaluated according to age, the increase in LP success rate was significant in children aged <12 months of age but not significant in children older than 12 months of age.

Conclusions:  Because of higher success rate, lateral decubitus, knee‐chest position with 45 degree head up tilt may be the preferred position for spinal anesthesia in infants.