bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of histological features, and description of histopathological lesions in thyroid glands from three species of free‐ranging sharks from the northwestern Atlantic, the blue shark, Prionace glauca (L.), the shortfin mako, Isurus oxyrhinchus Rafinesque, and the thresher, Alopias vulpinus (Bonnaterre)
Authors: Borucinska J D , Tafur M
Published: June 2009

Histomorphological features of piscine thyroids are widely accepted and frequently used as bioindicators of environmental pollution. This despite the fact that there is marked variation in thyroid morphology resulting from numerous pathological and physiological conditions. Our hypothesis was that there will be variations in histological features in thyroids collected from different shark species during the summer season in the northwestern Atlantic. To test our hypothesis, we examined histological features encountered in grossly normal thyroids from three species of sharks, the shortfin mako, Isurus oxyrhinchus, thresher, Alopias vulpinus and blue sharks, Prionace glauca. In addition, microscopic lesions from these thyroids were described. Ninety‐four sharks were collected in summer 2001, 2002 and 2004. Routine, haematoxylin and eosin‐stained paraffin‐embedded sections were studied by light microscopy. We found inter‐species but not intra‐species variation in histological patterns of thyroids, which were distinct enough to allow ‘blind’ assignment of a thyroid to the specific species. The most common lesions encountered were lymphofollicular hyperplasia and chronic thyroiditis. In addition, one case each of intravascular larval nematodes and a myxosporean infection was found. Our results provide the first data on species‐specific morphology of thyroids collected during summer months from sharks. The results indicate that familiarity with normal thyroid morphology is crucial before using shark thyroids in biomonitoring of environmental contamination or interpreting data from this gland in shark‐health studies.
Recovery approach to the care of people with dementia: decision making and ‘best interests’ concerns
Authors: MARTIN G.
Published: June 2009

Accessible summary

Dementia and decision making.

Relevance of the Mental Capacity Act 2005.

Recovery approach applied to people with dementia.

A model for change.

The concept of ‘recovery’ has been central to the discussion of the care of people with mental health problems in recent years, in this paper these ideas will be applied to the care of people with dementia in an attempt to focus nursing practice on the notion that it is possible to involve this group of patients in their own decision‐making processes. It is acknowledged that this is not always possible without support and advocacy by nurses and other carers who must take on board the need to arrive at solutions to problems or change that are in the person's best interests. The provisions of the Mental Capacity Act in 2005 are key to this discussion, and ways forward are recommended, which include a nursing model for change, in an effort to bring together the concepts addressed in this paper. The conclusion reached is that the recovery approach has some difficulties when applied to people with dementia but it remains an essential aspect of the care process which, together with the provisions of the Mental Capacity Act, could bring about radical improvements to the lives of this group of vulnerable people.
The nurse and the use of narrative: an approach to caring
Authors: ALOI J. A.
Published: June 2009

Accessible summary

Nurses at all levels of nursing practice can utilize the principles of narrative in the nurse–patient relationship.

The nurse can help patients discard negative story lines and rewrite the story with a preferred outcome.

This can be accomplished through the use of three main techniques: deconstruction, externalization and re‐authoring.

The use by the nurse of the principles of narrative therapy to help patients re‐author their personal narrative, and change it from a problem‐saturated story to one that is more preferred, is explored. Three main narrative techniques: deconstruction, externalization and re‐authoring are described. Examples of these techniques are provided to help nurses at all levels of nursing practice assume the role of collaborator in the re‐authoring process.
Families' experiences of interaction with the public health nurse at the child health clinic in connection with mother's post‐natal depression
Authors: TAMMENTIE T. , PAAVILAINEN E. , TARKKA M.‐T. , ÅSTEDT‐KURKI P.
Published: June 2009

Accessible summary

Mother's postnatal depression affects the functioning of the entire family.

Families felt lack of holistic cooperation at the child health clinics.

The birth of a new family member causes many changes in the way a family functions. Annually some 10% of mothers giving birth suffer from post‐natal depression. This depression affects the mother herself, the baby and the functioning of the entire family. The healthcare personnel are faced with an important task in supporting the family in the course of changes occasioned by the birth of a baby. According to earlier studies, families with small children are fairly satisfied with the service provided by the child health clinics. The purpose of the present study was to form a theory of interaction with the public health nurse in the child health clinic when the mother is suffering from post‐natal depression from the viewpoint of family. The data for the study were gathered by interviewing nine families (nine mothers and five fathers) where the mother had displayed symptoms of post‐natal depression. The data were analysed using continuous comparative analysis of grounded theory. The concepts of the theory emerged as a lack of continuing relationship, a need to be equal partners, a lack of individuality and a lack of family care. The relationships between categories were lack of discussing, lack of being confidential and lack of getting help enough. The core category emerging was lack of holistic cooperation with unique family. In spite of the emphasis placed on family centeredness in the operating principles of the work in child health clinics, its implementation in practical work cannot be taken for granted. Because of the limited resources available to the clinics, it is the experience of depressed mother in particular that they are not treated sufficiently as individuals and that they are subjected to adjudication in the clinics. The parents felt that the personality of the public health nurse was crucial to how they felt about the service they obtained from the clinic.
The role of intrusive and other recent life events on symptomatology in relapses of schizophrenia: a community nursing investigation
Authors: FALLON P.
Published: June 2009

Accessible summary

Increasing numbers of people with psychotic illnesses experienced life events, especially moderately threatening life events, in the last 4 weeks prior to relapse.

However, life events in general or specifically intrusive life events were not found to influence the type of psychotic symptoms people experienced.

People with established psychotic illnesses still experienced life events before relapse suggesting that chronic illness is not associated with absence of mild or moderately severe life events or with diminished sensitivity to them.

This study aimed to identify the impact of life events on psychotic relapse in individuals with an established diagnosis of schizophrenia to explore their proneness to experience life events, to examine if any effect of life events was cumulative or triggering in nature and to explore if specific types of events influence subsequent symptom formation. An association between adverse life events and relapse in people with schizophrenia has been reported in several studies; however, the nature of the association remains unclear. Some studies suggest that intrusive events promote the formation of paranoid psychotic symptoms. Using well‐validated semi‐structured interview schedules the author interviewed participants during or shortly after relapse. The severity and intrusiveness of life events was rated and relationships between events and symptoms were explored. Increasing numbers of patients experienced life events especially moderately threatening life events in the last 4 weeks prior to relapse; however, no relationship was discovered between life events in general or specifically intrusive life events and the specific content of psychotic symptoms. An increased frequency of milder life events occurred in the 2 months prior to relapse, suggesting that chronic illness is not associated with absence of mild or moderately severe life events or with diminished sensitivity to them.
Aggressive behaviour in adolescent psychiatric settings: what are risk factors, possible interventions and implications for nursing practice? A literature review
Authors: HAGE S. , VAN MEIJEL B. , FLUTTERT F. , BERDEN G. F. M. G.
Published: June 2009

Accessible summary

The aim of this literature review is to identify the risk factors of aggressive behaviour in adolescents and to describe available intervention strategies.

The risk factors comprise personal and environmental risk factors. Some risk factors can be influenced by nursing intervention strategies.

The most effective intervention programmes focus on interpersonal skills training in combination with parent management training.

There is a need for specific nursing intervention programmes to deal with aggressive behaviour in adolescent psychiatric settings.

This study was aimed to identify the risk factors of aggressive behaviour in adolescents (13–18 years), and to describe available intervention strategies. The findings are evaluated on the basis of their implications for nursing practice. Aggressive behaviour in adolescent psychiatric settings is a neglected research area. The consequences of aggressive behaviour on nurses, other patients and the therapeutic environment can be profound. For the development and implementation of innovative intervention strategies aimed at preventing aggressive behaviour in adolescent psychiatric patients, knowledge of risk factors and evidence‐based interventions for aggressive behaviour are of the utmost importance. A systematic search of PubMed, Cinahl, PsychINFO and Cochrane Systematic Reviews (1991–2007) was employed. The risk factors for aggressive behaviour comprise personal and environmental risk factors. Some risk factors can be influenced by nursing intervention strategies. Available intervention programmes range from interpersonal skills training to massage therapy, parent management training, functional family therapy and multi‐systemic therapy. The most effective programmes combine interpersonal skills training with parent management training. No specific nursing intervention programmes were found for dealing with aggressive behaviour in adolescent patients. Nursing staff can assist in achieving a systematic improvement in the treatment outcomes of existing intervention programmes for the prevention of aggression. There is a need for specific nursing intervention programmes to deal with aggressive behaviour in adolescent psychiatric settings.
Endophagy of biting midges attacking cavity‐nesting birds
Authors: VOTÝPKA J. , SYNEK P. , SVOBODOVÁ M.
Published: June 2009

Feeding behaviour, host preferences and the spectrum of available hosts determine the role of vectors in pathogen transmission. Feeding preferences of blood‐feeding Diptera depend on, among others factors, the willingness of flies to attack their hosts either in the open (exophagy) or in enclosed places (endophagy). As far as ornithophilic blood‐feeding Diptera are concerned, the biting midges (Diptera: Ceratopogonidae) and blackflies (Diptera: Simuliidae) are generally considered to be strictly exophagous. We determined which blood‐sucking Diptera enter nest cavities and feed on birds by placing sticky foil traps inside artificial nest boxes. A total of 667 females of eight species of biting midges of the genus Culicoides (Latreille, 1809) were captured on traps during 2006‐2007, with Culicoides truncorum (Edwards, 1939) being the dominant species. DNA blood analyses of blood‐engorged females proved that midges actually fed on birds nesting in the boxes. Three species were identified as endophagous: Culicoides truncorum, Culicoides pictipennis (Staeger, 1839), and Culicoides minutissimus (Zetterstedt, 1855). Our study represents the first evidence that ornithophilic biting midges are endophagous. The fact that we caught no blackflies in the bird boxes supports the exophagy of blackflies. We believe that our findings are important for surveillance programmes focusing on Diptera that transmit various bird pathogens.
Assessment of gene flow across a hybrid zone in red‐tailed chipmunks (Tamias ruficaudus)
Authors: HIRD SARAH , SULLIVAN JACK
Published: June 2009

The role of hybridization in animal speciation is controversial and recent research has challenged the long‐standing criterion of complete reproductive isolation to attain species status. The speciation‐with‐gene‐flow model posits that the genome is semi‐permeable and hybridization may be a phase in the process of divergence. Here, we apply these concepts to a previously identified zone of mtDNA introgression between the two strongly morphologically differentiated subspecies of red‐tailed chipmunk (Tamias ruficaudus) in the US Inland Northwest. Using multilocus genotype data from the southern, older contact zone, we demonstrate that neutral gene flow is unusually low between the subspecies across the Lochsa River. This is geographically congruent with the discontinuity in bacular morphology, indicating that the cline of mitochondrial DNA (mtDNA) haplotypes is displaced. Furthermore, we elucidate the evolutionary forces responsible by testing hypotheses of lineage sorting and hybridization. We determined that introgressive hybridization is the cause of mtDNA/morphology incongruence because there are non‐zero levels of migration and gene flow. Although our estimate of the age of the hybrid zone has wide credibility intervals, the hybridization events occurred in the Late Pleistocene and the divergence occurred in the Middle Pleistocene. Finally, we assessed substructure within and adjacent to the hybrid zone and found that the hybrid zone constitutes a set of populations that are genetically differentiated from parental sets of populations; therefore, hybridization in this system is not likely an evolutionary sink, but has generated novel combinations of genotypes.
Single‐queen introductions characterize regional and local invasions by the facultatively clonal little fire ant Wasmannia auropunctata
Authors: MIKHEYEV A. S. , BRESSON S. , CONANT P.
Published: June 2009

Clonal reproduction may facilitate the spread of invasive species by reducing the minimum population size necessary for successful establishment. We used microsatellite markers to reconstruct the composition of founding populations in two regional (Central Africa and Hawaii) and 23 local (near a Gabonese oilfield) invasions of the facultatively parthenogenetic little fire ant. Central Africa had a single dominant queen clone, which appears to have initiated the regional infestation, and then produced numerous other clones by rare sexual reproduction. This interpretation of the data was also supported by the genotype of a worker from the first collection in Africa (Gabon 1913). We found only a single queen clone in Hawaii, likewise indicating a single‐clone introduction, most likely from an earlier infestation in Florida. Single‐clone introductions also gave rise to the vast majority (92%) of local infestations at our oilfield study site. These results suggest the unusual, largely clonal, reproductive strategy of the little fire ant may enhance its success as an invasive species. However, the occasional sexual production of novel genotypes after the initial introduction may provide genetic flexibility that overcomes shortcomings of pure clonality.
Climate and agricultural context shape reproductive mode variation in an aphid crop pest
Authors: GILABERT A. , SIMON J.‐C. , MIEUZET L. , HALKETT F. , STOECKEL S. , PLANTEGENEST M. , DEDRYVER C.‐A.
Published: June 2009

In aphids, reproductive mode is generally assumed to be selected for by winter climate. Sexual lineages produce frost‐resistant eggs, conferring an advantage in regions with cold winters, while asexual lineages predominate in regions with mild winters. However, habitat and resource heterogeneities are known to exert a strong influence on sex maintenance and might modulate the effect of climate on aphid reproductive strategies. We carried out a hierarchical sampling in northern France to investigate whether reproductive mode variation of the aphidRhopalosiphum padiis driven by winter climate conditions, by habitat and resource heterogeneities represented by a range of host plants or by both factors. We confirmed the coexistence inR. padipopulations of two genetic clusters associated with distinct reproductive strategies. Asexual lineages predominated, whatever the surveyed year and location. However, we detected a between‐year variation in the local contribution of both clusters, presumably associated with preceding winter severity. No evidence for host‐driven niche differentiation was found in the field on six Poaceae among sexual and asexual lineages. Two dominant multilocus genotypes (∼70% of the sample), having persisted over a 10‐year period, were equally abundant on different plant species and locations, indicating their large ecological tolerance. Our results fit theoretical predictions of the influence of winter climate on the balance between sexual and asexual lineages. They also highlight the importance of current agricultural practices which seem to favour a small number of asexual generalist genotypes and their migration across large areas of monotonous environments.
Divergence with gene flow and fine‐scale phylogeographical structure in the wedge‐billed woodcreeper,Glyphorynchus spirurus, a Neotropical rainforest bird
Authors: MILÁ B. , WAYNE R. K. , FITZE P. , SMITH T. B.
Published: June 2009

Determining the relative roles of vicariance and selection in restricting gene flow between populations is of central importance to the evolutionary process of population divergence and speciation. Here we use molecular and morphological data to contrast the effect of isolation (by mountains and geographical distance) with that of ecological factors (altitudinal gradients) in promoting differentiation in the wedge‐billed woodcreeper,Glyphorynchus spirurus, a tropical forest bird, in Ecuador. Tarsus length and beak size increased relative to body size with altitude on both sides of the Andes, and were correlated with the amount of moss on tree trunks, suggesting the role of selection in driving adaptive divergence. In contrast, molecular data revealed a considerable degree of admixture along these altitudinal gradients, suggesting that adaptive divergence in morphological traits has occurred in the presence of gene flow. As suggested by mitochondrial DNA sequence data, the Andes act as a barrier to gene flow between ancient subspecific lineages. Genome‐wide amplified fragment length polymorphism markers reflected more recent patterns of gene flow and revealed fine‐scale patterns of population differentiation that were not detectable with mitochondrial DNA, including the differentiation of isolated coastal populations west of the Andes. Our results support the predominant role of geographical isolation in driving genetic differentiation inG. spirurus, yet suggest the role of selection in driving parallel morphological divergence along ecological gradients.
Microsatellite variation and population structure of the moor frog (Rana arvalis) in Scandinavia
Authors: KNOPP THERESA , MERILÄ JUHA
Published: June 2009

Several recent studies have found amphibian populations to be genetically highly structured over rather short geographical distances, and that the rate of genetically effective dispersal may differ between the sexes. However, apart from the common frog (Rana temporaria) little is known about the genetic structuring and sex‐biased dispersal in northern European amphibians. We investigated the patterns of genetic diversity and differentiation within and among Scandinavian populations of the moor frog (Rana arvalis) using microsatellite markers. The genetic diversity within local R. arvalis populations was not a simple linear negative function of latitude but a convex one: genetic diversity peaked in mid‐latitude populations, and declined thereafter dramatically towards the north. The average degree of genetic differentiation among populations (FST = 0.14) was lower than that observed for the common frog (FST = 0.21), though the pattern of isolation by distance was similar for both species. Contrary to common frogs, no evidence for female‐biased dispersal was found. The results reinforce the view that amphibian populations are—in general—highly structured over relatively small geographical distances, even in comparatively recently colonized areas.
Microarray analysis reveals transcriptional plasticity in the reef building coral Acropora millepora
Authors: BAY LINE K. , ULSTRUP KARIN E. , NIELSEN H. BJØRN , JARMER HANNE , GOFFARD NICOLAS , WILLIS BETTE L. , MILLER DAVID J. , VAN OPPEN MADELEINE J. H.
Published: June 2009

We investigated variation in transcript abundance in the scleractinian coral, Acropora millepora, within and between populations characteristically exposed to different turbidity regimes and hence different levels of light and suspended particulate matter. We examined phenotypic plasticity by comparing levels of gene expression between source populations and following 10 days of acclimatization to a laboratory environment. Analyses of variance revealed that 0.05% of genes were differentially expressed between source populations, 1.32% following translocation into a common laboratory and 0.07% in the interaction (source population‐dependent responses to translocation). Functional analyses identified an over‐representation of differentially expressed genes associated with metabolism and fluorescence categories (primarily downregulated), and environmental information processing (primarily upregulated) following translocation to a lower light and turbidity environment. Such metabolic downregulation may indicate nonoxidative stress, hibernation or caloric restriction associated with the changed environmental conditions. Green fluorescent protein‐related genes were the most differentially expressed and were exclusively downregulated; however, green fluorescent protein levels remained unchanged following translocation. Photophysiological responses of corals from both locations were characterized by a decline when introduced to the common laboratory environment but remained healthy (Fv/Fm > 0.6). Declines in total lipid content following translocation were the greatest for inshore corals, suggesting that turbid water corals have a strong reliance on heterotrophic feeding.
Personality differences affect brainstem autonomic responses to visceral pain
Authors: Paine P. , Worthen S. F. , Gregory L. J. , Thompson D. G. , Aziz Q.
Published: June 2009

Abstract Brainstem autonomic nuclei integrate interoceptive inputs including pain, with descending modulation, to produce homeostatic and defence outputs. Cardiac Vagal Control is especially implicated in psychophysiological processes for both health and disease and is indexed non‐invasively by heart rate variability. The study aim was to determine the nature of psychophysiological response profiles for visceral pain. Nineteen healthy subjects had electrocardiographic recordings at rest and during 10 painful oesophageal balloon distensions. Cardiac Vagal Control originating from nucleus ambiguus (CVCNA) was determined by polynomial filter application to the electrocardiogram inter‐beat interval series. Heart rate and ‘Cardiac Sympathetic Index (CSI)’ were also determined. Psychological state and trait, including neuroticism and extroversion, were assessed. Subjects who increased CVCNAto pain were more neurotic, anxious and sensory sensitive than those who decreased CVCNA.Cluster analysis identified two psychophysiological groups: Group 1 (n = 11) demonstrated lower baseline CVCNA(P = 0.0001), higher heart rate (P = 0.02) and CSI (P = 0.015), pain tolerance at lower balloon volumes (P = 0.04), but attenuated heart rate response to pain (P = 0.01). Group 2 (n = 8) had the converse profile. Neuroticism scores were higher (P = 0.0004) and extroversion lower (P = 0.01) for group 1 than group 2. Two distinct psychophysiological response profiles to visceral pain exist that are influenced by personality. These may reflect different psychobiological bases for active and passive defence repertoires. Prevalence and clinical relevance of these endophenotypes as vulnerability factors for pain and emotion disorders warrant further exploration.
Fall in density, but not number of myenteric neurons and circular muscle nerve fibres in guinea‐pig colon with ageing
Authors: Peck C. J. , Samsuria S. D. , Harrington A. M. , King S. K. , Hutson J. M. , Southwell B. R.
Published: June 2009

Abstract  In guinea‐pig ileum, ageing has been associated with a decrease in enteric neurons. This study examined guinea‐pig colon and measured changes in gut dimensions, neuron size, density and ganglionic area. Changes in motor nerve fibres in the circular muscle were also measured. Myenteric neurons in whole‐mount preparations of mid‐colon from 2‐week, 6‐month, and 2‐year‐old guinea‐pigs were labelled immunohistochemically with the neuronal marker human neuronal protein HuC/HuD, and numbers of neurons mm−2, neuronal size, ganglionic area mm−2, gut length, circumference and muscle thickness were measured. Corrected numbers of neurons mm−2 and ganglionic area mm−2 accounting for growth of the colon were calculated. Additionally, nerve fibres in circular muscle cross‐sections were labelled with antibodies against nitric oxide synthase (NOS) and substance P (SP) and the density of nerve fibres in circular muscle was measured. The numbers of neurons mm−2 decreased by 56% (from 2 weeks to 2 years) with no change in neuron size. Total neuron numbers decreased by 19% (P = 0.14) when adjusted for changes in length and circumference with age. The percentage area of NOS‐ and SP‐immunoreactive (IR) nerve fibres in the circular muscle decreased (P < 0.001), but the total area of NOS and SP‐IR nerve fibres increased (P < 0.01) due to an age‐related increase in muscle thickness. The density of myenteric neurons in guinea‐pig mid‐colon halved from 2 weeks to 2 years, but when the increase in colon dimensions was considered, the number of neurons decreased by only 19%. The percentage area of motor nerve fibres in the circular muscle decreased with no change in total volume of nerve fibres.
Ant cues affect the oviposition behaviour of fruit flies (Diptera: Tephritidae) in Africa
Authors: VAN MELE PAUL , VAYSSIERES JEAN‐FRANÇOIS , ADANDONON APPOLINAIRE , SINZOGAN ANTONIO
Published: June 2009

Abstract. Although most studies on fruit fly oviposition behaviour focus on horizontal interactions with competitors and cues from host plants, vertical interactions with predators are poorly documented. The present study provides direct evidence indicating that the oviposition behaviour of the two main mango fruit fly species, Ceratitis cosyra (Walker) and Bactrocera invadens Drew‐Tsurata & White, is affected by secretions of the dominant arboreal ant Oecophylla longinoda (Latreille). When offered ant‐exposed and unexposed mangoes in the absence of the ants, both fly species are reluctant to land on ant‐exposed fruits and, when having landed, often take off quickly and fail to oviposit. The number of puparia collected from unexposed mangoes is approximately eight‐fold higher than from ant‐exposed ones. The results obtained from laboratory experiments and field observations confirm that adult fruit flies are more affected through repellence by ant cues than by direct predation. The use of cues by fruit flies in predator avoidance has implications for evolutionary ecology, behavioural ecology and chemical ecology.
Short‐term Administration of Ethanol in Mice Deviates Antigen Presentation Activity Towards B Cells
Authors: Andrade M. C. , Albernaz M. J. S. , Araújo M. S. S. , Santos B. P. , Teixeira‐Carvalho A. , Faria A. M. C. , Martins‐Filho O. A.
Published: June 2009

Alcohol has a variety of short‐ and long‐term effects on cell‐mediated and humoral immune response. Herein, we have characterized the impact of high‐dose EtOH administration on phenotypic and functional features of murine APC subsets, including dendritic cell (DC), macrophages and B cells. Impaired cytokine synthesis and Leishmania‐phagocytosis was observed in peritoneal macrophages following EtOH administration. Moreover, EtOH exposure led to decreased levels of splenic myeloid DC and increased percentage of macrophages with no changes in splenic lymphoid DC and B cells. Adverse effects of short‐term EtOH administration also resulted in impaired OVA‐endocytosis by DC and macrophages. In contrast, EtOH consumption upregulates OVA‐internalization by B cells. These changes on APC hierarchy may play a role shifting the fate of the immune response after EtOH ingestion. In addition to an overall downregulation of Toll‐like receptor‐TLR‐4 expression by splenic APC, a downregulation of TLR‐2 expression in macrophages was observed. Moreover, EtOH exposure altered the expression of co‐signalling molecules on splenic APC, downregulating CD40 on macrophages and upregulating CD80 on B cells, with no impact on DC subsets. The net result of changes in TLR‐mediated and co‐stimulatory signals may determine the altered immunological status induced by acute consumption of alcohol. A direct impact of high‐dose EtOH administration in the activation status of splenic CD4+ T cells was observed. Together, our results demonstrated that short‐term high‐dose EtOH administration has differential impact on APC populations, downregulating splenic macrophages and DC activity but up‐regulating B lymphocyte function as APC, and ultimately yielding a micro‐environment that led to increased activation of CD4+ T cells.
The Elevated Interferon Gamma Production is an Important Immunological Marker in HAM/TSP Pathogenesis
Authors: Montanheiro P. A. , Penalva de Oliveira A. C. , Smid J. , Fukumori L. M. I. , Olah I. , Duarte A. J. da S. , Casseb J.
Published: June 2009

Human T‐lymphotropic virus type 1 (HTLV‐1) is the agent of the HTLV‐1‐associated myelopathy/tropical spastic paraparesis (HAM/TSP), which may occur in >5% of patients during their lifetime. HTLV‐1‐infection causes disturbances in the immune system, and the viral load may also play an important role in the pathogenesis of HAM/TSP. Some cytokines are involved in the pathogenesis of this disorder. We have determined IL‐2, IL‐4, IL‐10, IL‐12 p70, IFN‐γ and TNF‐α production among HTLV‐1‐infected subjects from our HTLV‐out Clinic in Institute of Infectious ‘Emílio Ribas’ in Sao Paulo city, Brazil. PBMC obtained from healthy controls (n = 32), asymptomatic HTLV‐1 carriers (n = 68) and HAM/TSP patients (n = 44) were grown in the absence and in the presence of phytohaemagglutinin (PHA), and the supernatants’ fluids were measured for cytokines production. IL‐2 levels were increased in the asymptomatic HTLV‐1 carriers, and IFN‐γ was increased in both groups of patients (asymptomatic HTLV‐1 carriers and more significantly among HAM/TSP patients). IL‐4, IL‐10, TNF‐α and IL‐12 p70 levels were not significantly increased on both groups of patients, as compared with controls. The major finding of this study is that IFN‐γ was an important cytokine for the HAM/TSP pathogenesis. Therefore, immune modulation of IFN‐γ may be critical to treat of HAM/TSP patients.
The Role of Natural Killer Cells in Resistance to the Intracellular Bacterium Listeria monocytogenes in Rats
Authors: Shegarfi H. , Sydnes K. , Løvik M. , Inngjerdingen M. , Rolstad B. , Naper C.
Published: June 2009

We have investigated the influence of early innate immune resistance mechanisms on infection with the intracellular bacterium Listeria monocytogenes in rats. Rats were injected i.v. with various amounts of Listeria and the number of bacterial colonies in the spleen was determined at different time points after infection. A bacterial dose as low as 2 × 104 cells gave reproducible infection within the spleen. Athymic nude rats lacking normal T cells but with a robust NK cell repertoire for MHC antigens were more resistant to bacterial replication within the spleen than were normal littermate rats and eliminated the infection within 3 days. In vivo depletion of NK cells, or NK subpopulations expressing Ly49 receptors, increased the bacterial load in the spleen, indicating that these cells were important in the initial control of Listeria infection. An increased frequency of Ly49 expressing NK cells in Listeria‐infected rats further supported this notion. As several rat strains, unlike mice, display a large repertoire of MHC‐recognizing activating Ly49 receptors, these observations raise the interesting possibility that NK cells may recognize alterations in the MHC‐I molecules on Listeria‐infected cells leading to their elimination before the adaptive immune system comes into play.
A plant thiolase involved in benzoic acid biosynthesis and volatile benzenoid production
Authors: Moerkercke Alex Van , Schauvinhold Ines , Pichersky Eran , Haring Michel A. , Schuurink Robert C.
Published: June 2009

The exact biosynthetic pathways leading to benzoic acid (BA) formation in plants are not known, but labeling experiments indicate the contribution of both β‐oxidative and non‐β‐oxidative pathways. In Petunia hybrida BA is a key precursor for the production of volatile benzenoids by its flowers. Using functional genomics, we identified a 3‐ketoacyl‐CoA thiolase, PhKAT1, which is involved in the benzenoid biosynthetic pathway and the production of BA. PhKAT1 is localised in the peroxisomes, where it is important for the formation of benzoyl‐CoA‐related compounds. Silencing of PhKAT1 resulted in a major reduction in BA and benzenoid formation, leaving the production of other phenylpropanoid‐related volatiles unaffected. During the night, when volatile benzenoid production is highest, it is largely the β‐oxidative pathway that contributes to the formation of BA and benzenoids. Our studies add the benzenoid biosynthetic pathway to the list of pathways in which 3‐ketoacyl‐CoA thiolases are involved in plants.
Characterization of HLA‐G expression in renal cell carcinoma
Authors: Li B.‐L. , Lin A. , Zhang X.‐J. , Zhang X. , Zhang J.‐G. , Wang Q. , Zhou W.‐J. , Chen H.‐X. , Wang T.‐J. , Yan W.‐H.
Published: June 2009

Previous studies showed that human leukocyte antigen (HLA)‐G is specifically upregulated in renal cell carcinoma (RCC). However, a larger cohort of RCC patients are necessary to obtain more information. In this study, 109 RCC primary lesions (clear cell, n = 95; chromophobe, n = 4; papillary, n = 4; collecting duct, n = 6) and corresponding adjacent tumor‐negative renal tissues (n = 34) were analyzed for the HLA‐G expression by immunohistochemistry (IHC). Meanwhile, plasma soluble HLA‐G (sHLA‐G) from 16 RCC patients and 144 sex‐ and age‐matched normal individuals was detected by enzyme‐linked immunosorbent assay. Correlations between lesion HLA‐G expression and various clinical parameters were evaluated. Receiver‐operating characteristic (ROC) curve analysis was used to determine the feasibility of HLA‐G protein staining and sHLA‐G as a diagnosis marker for RCC. IHC data showed that HLA‐G was observed in 49.5% of clear cell, 50% of either chromophobe or collecting duct RCC lesions but undetectable in papillary RCC and tumor‐negative renal tissues. This finding was consistent with the western blot results. sHLA‐G was pronouncedly increased in RCC patients when compared with normal controls (median: 39.5 vs 19.2 U/ml, P = 0.002). However, no correlation was observed between HLA‐G expression and various clinical parameters. We found that the area under ROC curve for HLA‐G expression and sHLA‐G was 0.739 [95% confidence interval (95% CI): 0.659–0.816, P = 0.000] and 0.733 (95% CI: 0.619–0.847, P = 0.002), respectively. Our findings indicated that, except the papillary RCC, other types of RCC could express HLA‐G. Furthermore, both lesion HLA‐G expression and plasma sHLA‐G level might be a useful preoperative biomarker for diagnosis.
Role of phosphoglucosamine mutase on virulence properties of Streptococcus mutans
Authors: Liu X. D. , Duan J. , Guo L. H.
Published: June 2009

Introduction:  Streptococcus mutans has been strongly implicated as the principal etiological agent in dental caries. As a gram‐positive bacterium, S. mutans has a thick and compact cell wall to maintain the cell shape and protect the cells against mechanical or osmotic damage. Previous studies have proved that peptidoglycan is the main component of the cell wall involved in the autolysis or biofilm formation processes.

Methods:  In this study, we investigated the gene SMU.1426c in the amino‐sugar metabolism pathway of S. mutans UA159, which encodes phosphoglucosamine mutase (GlmM). The glmM gene that functions in the biosynthesis of peptidoglycan has been well investigated in Escherichia coli. Here a glmM mutant strain of S. mutans UA159 was constructed and several virulence properties were investigated.

Results:  The mutant devoid of the glmM gene displayed long chains, reduced growth rate and increased autolysis. Biofilm formation by the mutant was found to be attenuated.

Conclusion:  These results proved that peptidoglycan biosynthesis plays an important part in a series of bacterial morphologies. The glmM gene may have a constructive role in the virulence properties of S. mutans.
Bacteriophages induced from lysogenic root canal isolates of Enterococcus faecalis
Authors: Stevens R. H. , Porras O. D. , Delisle A. L.
Published: June 2009

Introduction:  Bacterial viruses play crucial roles in the pathogenesis of many systemic diseases. They are known to inhabit the oral cavity, both as free virions and as prophages in lysogenic bacterial strains; however, there has been no report of bacteriophages in endodontic infections. In this study, we sought to detect, isolate, and describe temperate bacteriophages harbored by Enterococcus faecalis strains isolated from endodontic infections.

Methods:  Ten E. faecalis strains were isolated from root canals of teeth undergoing retreatment following unsuccessful endodontic therapy. Mitomycin C was used to induce any prophages present in the bacterial isolates. The induced phages were purified and examined using electron microscopy. The DNA extracted from one of the phage isolates was subjected to restriction endonuclease digestion and agarose electrophoresis analysis.

Results:  Lysogeny was demonstrated in 4 of the 10 E. faecalis strains. Three of the lysogenic strains yielded phages exhibiting a Siphoviridae morphology, with long, non‐contractile tails 130 nm in length, and spherical/icosahedral heads 41 nm in diameter. The virus induced from the fourth lysogenic E. faecalis strain had a contractile tail characteristic of Myoviridae. Restriction endonuclease analysis of NsiI and NdeI DNA fragments from one of the Siphoviridae phage isolates (phage φEf11) indicated a genome size of approximately 41 kbp.

Conclusion:  This is the first report of lysogenic bacteria and their inducible viruses in infected root canals.
Does the frequency of Prevotella intermedia increase during pregnancy?
Authors: Gürsoy M. , Haraldsson G. , Hyvönen M. , Sorsa T. , Pajukanta R. , Könönen E.
Published: June 2009

Introduction:  The former Bacteroides intermedius, currently including Prevotella intermedia and Prevotella nigrescens, has been associated with hormone‐induced pregnancy gingivitis. The aim of the present longitudinal study was to determine whether only P. intermedia or P. nigrescens, or both species, are involved in the demonstrated microbial shift during pregnancy.

Methods:  Subgingival plaque and saliva samples, collected from 30 healthy pregnant women and 24 healthy non‐pregnant women as their controls, were examined for the presence of pigmented gram‐negative anaerobes. Altogether 2628 isolates were preliminarily identified as P. intermedia sensu lato, based on phenotypic testing. Their further identification was performed by using a 16S ribosomal DNA‐based polymerase chain reaction (PCR).

Results:  A mean of 8.3 P. intermedia sensu lato isolates from each subject/sampling was examined. During the second trimester, the mean number of P. intermedia sensu lato in plaque increased along with increasing signs of pregnancy gingivitis, and then both decreased. After delivery, gingival inflammation still decreased while the number of P. intermedia sensu lato transiently increased both in plaque and saliva. In the present study, the vast majority of isolates (95.3%) proved to be P. nigrescens and 2.5% were P. intermedia. The remaining 2.2% of the isolates could not be identified with PCR as P. intermedia or P. nigrescens. The corresponding percentages in the control population were 94.2%, 5.5%, and 0.3%.

Conclusion:  In the oral cavity of relatively young women without periodontitis, P. nigrescens, unlike P. intermedia, is a frequent finding. Conceivably, pregnant women harbor increasing numbers of P. nigrescens associated with pregnancy gingivitis.
Identification of oral species of the genus Veillonella by polymerase chain reaction
Authors: Igarashi E. , Kamaguchi A. , Fujita M. , Miyakawa H. , Nakazawa F.
Published: June 2009

Introduction:  Members of the genus Veillonella cannot be reliably distinguished by their biochemical characteristics and phenotypic features. Moreover, DNA–DNA hybridization and sequence analyses of the 16S ribosomal RNA gene including random fragment length polymorphism analysis, are complex and time‐consuming procedures that are not well‐suited to identifying oral species of Veillonella: Veillonella atypica, Veillonella denticariosi, Veillonella dispar, Veillonella parvula, and Veillonella rogosae.

Methods:  In this study, five forward primers and a reverse primer were designed for polymerase chain reaction (PCR) according to the partial sequences of the rpoB genes of these oral Veillonella species.

Results:  The forward primers were species‐specific for these five Veillonella species, and could produce specific amplicons when used together with reverse primer and individual DNA templates of these species in PCR. These primer pairs were also found to discriminate between the respective species, and the Veillonella strains isolated from human oral cavities were successfully assigned to one of the five oral species of the genus Veillonella based on their specific products by PCR.

Conclusion:  A simple two‐step PCR procedure using the five sets of primer pairs developed in the present study is a rapid and reliable method for the identification of the recognized oral Veillonella species.
Prevalence and molecular diversity of Archaea in subgingival pockets of periodontitis patients
Authors: Li C. L. , Liu D. L. , Jiang Y. T. , Zhou Y. B. , Zhang M. Z. , Jiang W. , Liu B. , Liang J. P.
Published: June 2009

Introduction:  The aim of this study was to investigate the prevalence and molecular diversity of Archaea in the subgingival crevices of patients with chronic periodontitis.

Methods:  Subgingival plaque was collected from 41 patients with chronic periodontitis and 15 healthy subjects. The prevalence of Archaea in those plaque samples was tested by polymerase chain reaction with two broad‐range archaeal primer sets. Amplicons from eight Archaea‐positive plaque samples were cloned and sequenced for molecular diversity analysis using one of these two primer sets and a novel third primer set.

Results:  Archaea were detected in the subgingival plaque of patients with chronic periodontitis at a prevalence of 70.7–73.2%, but were not detected in healthy subjects. Using one primer set, all sequences of the archaeal amplicons were identified as Methanobrevibacter oralis‐like species. With another primer set, the amplicons were also found to be identical to the uncultured M. oralis‐like species except one phylotype was found to belong to the class Thermoplasmata.

Conclusion:  Archaea might be correlated with periodontal diseases. The diversity of Archaea associated with periodontitis was limited. Almost all sequenced amplicons fell into the genus Methanobrevibacter of the Euryarcheota phylum. M. oralis‐like species was the predominant but non‐exclusive archaeon in the subgingival dental plaque of patients with periodontitis.
Progressive increase of human papillomavirus carriage rates in potentially malignant and malignant oral disorders with increasing malignant potential
Authors: Szarka K. , Tar I. , Fehér E. , Gáll T. , Kis A. , Tóth E. D. , Boda R. , Márton I. , Gergely L.
Published: June 2009

Introduction:  We investigated the potential role of human papillomaviruses (HPVs) in potentially malignant oral disorders, oral leukoplakia (OL) and oral lichen planus (OLP), and in oral squamous cell cancer (OSCC) in an Eastern Hungarian population with a high incidence of OSCC.

Methods:  Excised tumor samples (65 OSCC patients) and exfoliated cells from potentially malignant lesions (from 44 and 119 patients with OL and OLP, respectively) as well as from healthy controls (72 individuals) were analysed. OLPs were classified based on clinical appearance, 61 patients had erosive–atrophic lesions (associated with higher malignancy risk, EA‐OLP) and 58 had non‐erosive non‐atrophic lesions (with lower risk of becoming malignant, non‐EA‐OLP), respectively. Exfoliated cells collected from apparently healthy mucosa accompanied each lesion sample. HPV was detected by MY/GP polymerase chain reaction (PCR) and genotyped by restriction analysis of amplimers. Copy numbers in lesions were determined using real‐time PCR. Prevalence rates, copy number distributions, and association with risk factors and diseases were analysed using chi‐square test, t‐test, and logistic regression, respectively.

Results:  We detected HPVs significantly more frequently in lesions than in controls (P ≤ 0.001 in all comparisons). HPV prevalence increased gradually with increasing severity of lesions (32.8, 40.9, and 47.7% in OLP, OL, and OSCC, respectively). Copy number distribution patterns roughly corresponded to prevalence rates, but OLP and OL were comparable. HPV prevalence differed significantly between EA‐OLP and non‐EA‐OLP groups (42.6 vs. 22.4%); EA‐OLP group showed a prevalence similar to that found in OL.

Conclusion:  HPVs may be involved in the development or progression of not only OSCC but also of potentially malignant oral lesions.