bluuebunny/crossref_metadata_2025 huggingface dataset:
APJ Receptor mRNA Expression in the Rat Hypothalamic Paraventricular Nucleus: Regulation By Stress and Glucocorticoids
Authors: O'Carroll A.‐M. , Don A. L. J. , Lolait S. J.
Published: October 2003

The apelin receptor (APJ receptor, APJR) has recently come to prominence following the isolation and identification of its endogenous ligand, apelin, from bovine stomach tissue extracts. Investigation of APJR mRNA expression has revealed a hypothalamic distribution similar to that of vasopressin suggesting that the apelin–APJR system may be involved in the regulation of the hypothalamic‐adrenal‐pituitary (HPA) stress axis. To investigate whether APJR is involved in the regulation of hypothalamic function during stress, APJR mRNA expression levels were measured by in situ hybridization in the hypothalamus of rats subjected to acute and repeated restraint stress. Acute stress caused an increase in APJR mRNA expression in the hypothalamic parvocellular paraventricular nucleus (pPVN) while repeated restraint stress induced a sustained up‐regulation of pPVN APJR mRNA expression in intact rats. Removal of endogenous glucocorticoids by adrenalectomy also resulted in an increased expression of APJR mRNA in the PVN, suggesting a negative regulation of APJR mRNA expression by glucocorticoids. The role of glucocorticoids in mediating these stress‐induced changes was investigated by analysing the effects of acute and repeated restraint stress on APJR mRNA levels in adrenalectomized rats. In these rats, APJR mRNA expression levels did not change above the already elevated levels of adrenalectomized‐control rats. These data suggest that acute and repeated stress exert a stimulatory influence on APJR mRNA expression at the hypothalamic level that may be dependent on basal levels of circulating glucocorticoids, and further suggest a role for APJR in the regulation of hypothalamic function.
Genes encoding a cellulosic polymer contribute toward the ecological success of Pseudomonas fluorescens SBW25 on plant surfaces
Authors: Gal Micaela , Preston Gail M. , Massey Ruth C. , Spiers Andrew J. , Rainey Paul B.
Published: October 2003

Pseudomonas fluorescens SBW25 is a Gram‐negative bacterium that grows in close association with plants. In common with a broad range of functionally similar bacteria it plays an important role in the turnover of organic matter and certain isolates can promote plant growth. Despite its environmental significance, the causes of its ecological success are poorly understood. Here we describe the development and application of a simple promoter trapping strategy (IVET) to identify P. fluorescens SBW25 genes showing elevated levels of expression in the sugar beet rhizosphere. A total of 25 rhizosphere‐induced (rhi) fusions are reported with predicted roles in nutrient acquisition, stress responses, biosynthesis of phytohormones and antibiotics. One rhi fusion is to wss, an operon encoding an acetylated cellulose polymer. A mutant carrying a defective wss locus was competitively compromised (relative to the wild type) in the rhizosphere and in the phyllosphere, but not in bulk soil. The rhizosphere‐induced wss locus therefore contributes to the ecological performance of SBW25 in the plant environment and supports our conjecture that genes inactive in the laboratory environment, but active in the wild, are likely to be determinants of fitness in natural environments.
Population dynamics and gene transfer in genetically modified bacteria in a model microcosm
Authors: Lilley A. K. , Bailey M. J. , Barr M. , Kilshaw K. , Timms‐Wilson T. M. , Day M. J. , Norris S. J. , Jones T. H. , Godfray H. C. J.
Published: October 2003

The horizontal transfer and effects on host fitness of a neutral gene cassette inserted into three different genomic loci of a plant‐colonizing pseudomonad was assessed in a model ecosystem. The KX reporter cassette (kanamycin resistance, aph, and catechol 2, 3, dioxygenase, xylE) was introduced on the disarmed transposon mini‐Tn5 into: (I) the chromosome of a spontaneous rifampicin resistant mutant Pseudomonas fluorescens SBW25R; (II) the chromosome of SBW25R in the presence of a naturally occurring lysogenic‐phage (phage Φ101); and (III) a naturally occurring plasmid pQBR11 (330 kbp, tra+, Hgr) introduced into SBW25R. These bacteria were applied to Stellaria media (chickweed) plants as seed dressings [c. 5 × 104 colony‐forming units (cfu)/seed] and the seedlings planted in 16 microcosm chambers containing model plant and animal communities. Gene transfer to pseudomonads in the phyllosphere and rhizosphere was found only in the plasmid treatment (III). Bacteria in the phage treatment (II) initially declined in density and free phage was detected, but populations partly recovered as the plants matured. Surprisingly, bacteria in the chromosome insertion treatment (I) consistently achieved higher population densities than the unmanipulated control and other treatments. Plasmids were acquired from indigenous bacterial populations in the control and chromosome insertion treatments. Plasmid acquisition, plasmid transfer from inocula and selection for plasmid carrying inocula coincided with plant maturation.
Evidence for genetic monogamy and female‐biased dispersal in the biparental mouthbrooding cichlid Eretmodus cyanostictus from Lake Tanganyika
Authors: Taylor Martin I. , Morley Josephine Isabelle , Rico Ciro , Balshine Sigal
Published: October 2003

In this study, we investigate whether apparent social monogamy (where a species forms a pair bond but may participate in copulations outside the pair bond) corresponds with genetic monogamy (where individuals participate only in copulations within a pair bond) in a biparental mouthbrooding cichlid fish, Eretmodus cyanostictus, from Lake Tanganyika, Africa. Our findings suggest that E. cyanostictus is both socially and genetically monogamous and that monogamy may result from limited opportunities for polygyny, rather than from reproductive benefits of monogamy. Mating systems are believed to influence the relative rate of dispersal of the sexes, and our results suggest that E. cyanostictus displays female‐biased dispersal, providing some support for the ‘resource competition’ hypothesis driving sex‐biased dispersal.
Interspecific hybridization in plant‐associated fungi and oomycetes: a review
Authors: Schardl C. L. , Craven K. D.
Published: October 2003

Fungi (kingdom Mycota) and oomycetes (kingdom Stramenopila, phylum Oomycota) are crucially important in the nutrient cycles of the world. Their interactions with plants sometimes benefit and sometimes act to the detriment of humans. Many fungi establish ecologically vital mutualisms, such as in mycorrhizal fungi that enhance nutrient acquisition, and endophytes that combat insects and other herbivores. Other fungi and many oomycetes are plant pathogens that devastate natural and agricultural populations of plant species. Studies of fungal and oomycete evolution were extraordinarily difficult until the advent of molecular phylogenetics. Over the past decade, researchers applying these new tools to fungi and oomycetes have made astounding new discoveries, among which is the potential for interspecific hybridization. Consequences of hybridization among pathogens include adaptation to new niches such as new host species, and increased or decreased virulence. Hybrid mutualists may also be better adapted to new hosts and can provide greater or more diverse benefits to host plants.
A morphological cline inEucalyptus: a genetic perspective
Authors: Holman James E. , Hughes Jane M. , Fensham Rod J.
Published: October 2003

The putative hybrid zone betweenEucalyptus populneaandE. browniiis examined using morphological and molecular techniques. This species complex displays continuous morphological variation across the study area, which has been previously interpreted as the product of hybridization between allopatric species. A microsatellite analysis indicates that there was little genetic structuring across the morphological cline and only low levels of population differentiation. The nested clade analysis of the JLA+region of the chloroplast DNA (cpDNA) indicates that the geographical distribution of cpDNA haplotypes is unlikely to be the result of historical hybridization events, and that restricted seed‐mediated gene flow with isolation by distance is responsible for the phylogeographical distribution. A more plausible explanation for the origin and persistence of the morphological cline is that the process of continuous morphological diversification has been promoted by a directional selection gradient. This study addresses species status withinEucalyptusand the belief that hybridization is widespread and is an important process in the group's evolution.
Wood ingestion by passalid beetles in the presence of xylose‐fermenting gut yeasts
Authors: Suh Sung‐Oui , Marshall Christopher J. , Mchugh Joseph V. , Blackwell Meredith
Published: October 2003

During a survey of insect gut micro‐organisms, we consistently isolated Pichia stipitis‐like yeasts (Fungi: Ascomycota, Saccharomycetes) from the wood‐ingesting beetles, Odontotaenius disjunctus and Verres sternbergianus (Coleoptera: Passalidae). The yeasts were isolated from passalid beetles over a wide area, including the eastern and midwestern USA and Panama. Phylogenetic analyses of the nuclear encoded small and large subunit rRNA gene (rDNA) sequences distinguished a well‐supported clade consisting of the passalid yeasts and Pichia stipitis, P. segobiensis, Candida shehatae and C. ergatensis. Members of this clade have the ability to ferment and assimilate xylose or to hydrolyse xylan, major components of the polysaccharide, hemicellulose. Sexual reproduction was present in the passalid isolates but was rare among the gut yeasts of other beetles to which they were compared. Minor genetic and phenotypic variation among some of the passalid yeasts was detected using markers from the internal transcribed spacer region of the rDNA repeat unit, morphology, and in vitro metabolic tests. The consistent association of xylose‐fermenting yeasts of almost identical genotypes with passalid beetles across a broad geographical distribution, suggests a significant symbiotic association.
Cytonuclear disequilibrium in a hybrid zone involving deep‐sea hydrothermal vent mussels of the genus Bathymodiolus
Authors: Won Y. , Hallam S. J. , O'Mullan G. D. , Vrijenhoek R. C.
Published: October 2003

A hybrid zone involving the deep‐sea mussels, Bathymodiolus azoricus and B. puteoserpentis, was recently discovered at Broken Spur hydrothermal vent field (29°10′ N, 43°10′ W) along an intermediate segment of the Mid‐Atlantic Ridge axis. Examination of nuclear (allozymes) and cytoplasmic (mitochondrial DNA) gene markers in a new sample from Broken Spur revealed significant cytonuclear disequilibrium caused by an excess of the parental types (coupling phase) and a deficiency of recombinants (repulsion phase). An assignment test of individual multilocus genotypes also revealed an excess of parental genotypes in the admixed population. These results support the hypothesis that the Broken Spur mussel population comprises a nonequilibrium mixture of parental immigrants and hybrid individuals.
Long‐term temporal changes of genetic composition in brown trout (Salmo truttaL.) populations inhabiting an unstable environment
Authors: Østergaard Siri , Hansen Michael M. , Loeschcke Volker , Nielsen Einar E.
Published: October 2003

The genetic structure of brown trout (Salmo trutta) populations inhabiting rivers on the island of Bornholm in the Baltic Sea was studied on a spatial and temporal scale. Low water levels in the rivers during the summer period are assumed to have a significant impact on the persistence of local populations, possibly resulting in a metapopulation structure. Extinctions may, however, also be buffered by a remnant strategy, whereby juveniles escape to river outlets during periods of drought. We compared polymorphism at seven microsatellite DNA loci in contemporary and past samples collected from 1944 to 1997. A principal component analysis, a hierarchical gene diversity analysis and assignment tests showed that the genetic composition of populations was not temporally stable, and that temporal genetic differentiation was much stronger than spatial differentiation. Genetic variability was high and stable over time. Effective population sizes (Ne) and migration rate (m) were estimated using a maximum‐likelihood‐based implementation of the temporal method.Neestimates were low (ranging from 8.3 to 22.9) and estimates ofmwere high (between 0.23 and 0.99), in contrast to other Danish trout populations inhabiting larger and more environmentally stable rivers (Nebetween 39.2 and 289.9 andmbetween 0.01 and 0.09). Thus, the observed spatio‐temporal patterns of genetic differentiation can be explained by drift in small persisting populations, where levels of genetic variation are maintained by strong gene flow. However, observations of rivers devoid of trout suggested that population turnover also takes place. We suggest that Bornholm trout represent a metapopulation where the genetic structure primarily reflects strong drift and gene flow, combined with occasional extinction–recolonization events.
Phylogeography of Biomphalaria glabrata and B. pfeifferi, important intermediate hosts of Schistosoma mansoni in the New and Old World tropics
Authors: Dejong R. J. , Morgan J. A. T. , Wilson W. D. , Al‐Jaser M. H. , Appleton C. C. , Coulibaly G. , D’Andrea P. S. , Doenhoff M. J. , Haas W. , Idris M. A. , Magalhães L. A. , Moné H. , Mouahid G. , Mubila L. , Pointier J.‐P. , Webster J. P. , Zanotti‐Magalhães E. M. , Paraense W. L. , Mkoji G. M. , Loker E. S.
Published: October 2003

The historical phylogeography of the two most important intermediate host species of the human blood fluke Schistosoma mansoni, B. glabrata in the New World, and B. pfeifferi in the Old World, was investigated using partial 16S and ND1 sequences from the mitochondrial genome. Nuclear sequences of an actin intron and internal transcribed spacer (ITS)‐1 were also obtained, but they were uninformative for the relationships among populations. Phylogenetic analyses based on mtDNA revealed six well‐differentiated clades within B. glabrata: the Greater Antilles, Venezuela and the Lesser Antilles, and four geographically overlapping Brazilian clades. Application of a Biomphalaria‐specific mutation rate gives an estimate of the early Pleistocene for their divergence. The Brazilian clades were inferred to be the result of fragmentation, due possibly to climate oscillations, with subsequent range expansion producing the overlapping ranges. Within the Venezuela and Lesser Antilles clade, lineages from each of these areas were estimated to have separated approximately 740 000 years ago. Compared to B. glabrata, mitochondrial sequences of B. pfeifferi are about 4× lower in diversity, reflecting a much younger age for the species, with the most recent common ancestor of all haplotypes estimated to have existed 880 000 years ago. The oldest B. pfeifferi haplotypes occurred in southern Africa, suggesting it may have been a refugium during dry periods. A recent range expansion was inferred for eastern Africa less than 100 000 years ago. Several putative species and subspecies, B. arabica, B. gaudi, B. rhodesiensis and B. stanleyi, are shown to be undifferentiated from other B. pfeifferi populations.
Population structure of the pumpkin fruit flyBactrocera depressa(Tephritidae) in Korea and Japan: Pliocene allopatry or recent invasion?
Authors: Mun Jeomhee , Bohonak Andrew J. , Roderick George K.
Published: October 2003

Because of their widespread agricultural impact and rapid range expansions, true fruit flies (Tephritidae) are the subject of quarantine and control efforts worldwide. Among these flies, the pumpkin fruit flyBactrocera depressa,which infests squash and other cucurbitaceous plants in Korea, Japan and Taiwan, was recently isolated from produce shipments entering Japan and identified as a regulatory target. This species was described in 1933 from collections in Japan and discovered in 1974 in Korea, suggesting that it may have recently invaded mainland Asia. We analysed the genetic structure of Asian populations ofB. depressausing sequence variation for mitochondrial genecytochrome‐oxidaseI and three nuclear loci:elongation factor1α,tubulinβ1 andtubulinβ3, using frequency‐based approaches, nested clade analysis and assignment tests. Contrary to the hypothesis of recent invasion, high levels of genetic subdivision were found among five Korean and three Japanese populations. Nested clade analysis suggested a variety of processes operating over different time scales, including ancient isolation between Korea and Japan and more recent range expansions within each country. Contrary to a priori expectations, the results also suggested the recent introduction of a mitochondrial haplotype into Yokohama, Japan that is related closely to a widespread haplotype found throughout Korea. Assignment tests also supported these conclusions. The combination of a genealogical approach and probabilistic assignments of individuals to populations of origin was able to provide statistical support for the identification of cryptic introductions within an otherwise widespread indigenous species.
The distribution and evolutionary history ofWolbachiainfection in native and introduced populations of the invasive argentine ant (Linepithema humile)
Authors: Tsutsui Neil D. , Kauppinen Seth N. , Oyafuso Alain F. , Grosberg Richard K.
Published: October 2003

Wolbachia pipientisis a maternally transmitted bacterium that often alters the life history of its insect host to maximize transmission to subsequent generations. Here we report on the frequency and distribution ofWolbachiainfection in a widespread invasive species, the Argentine ant (Linepithema humile). We screened 1175 individual Argentine ants from 89 nests on five continents and several islands, including numerous locations in both the native (South American) and introduced ranges. We detectedWolbachiain four of 11 native populations, but only one of 21 introduced populations was infected. In the Argentine ant's native range, the distribution ofWolbachiasupergroups A and B was nonoverlapping. By coupling infection frequency data with behaviourally defined colony boundaries, we show that infected and uninfected colonies are often adjacent to one another, supporting the proposition that little female‐mediated gene flow occurs among Argentine ant colonies. We also conduct a phylogenetic analysis, and show that theWolbachiainfecting both native and introduced populations of Argentine ants belong to two lineages that appear to be specialized on infecting New World ants. One other lineage ofWolbachiahas undergone frequent, recent episodes of horizontal transmission between distantly related, introduced insect hosts.
Genetic structure, conservation genetics and evidence of speciation by range expansion in shy and white‐capped albatrosses
Authors: Abbott Cathryn L. , Double Michael C.
Published: October 2003

Six variable microsatellite loci were used to examine genetic structuring in the closely related shy albatross (Thalassarche cauta) and white‐capped albatross (T. steadi). First, levels of genetic differentiation between the species, and among three populations within each species, were analysed using amova, FST and RST. We found high levels of genetic structuring and detected many unshared alleles between the species, which provide strong evidence against any contemporary gene flow between them. Within each species, shy albatross populations were found to be genetically distinct whereas white‐capped albatross populations were undifferentiated, which implies that dispersal events are much rarer in the former than in the latter. These results formed the basis for the recommendation that the three white‐capped albatross populations (as a whole) and each shy albatross population be treated as separate units for conservation. Second, levels of genetic diversity and allelic patterns in shy and white‐capped albatrosses were assessed for whether they support earlier mtDNA results suggesting that shy albatrosses arose through range expansion of white‐capped albatrosses. All measures indicated lower genetic diversity within shy albatrosses than within white‐capped albatrosses and upheld the hypothesis that shy albatrosses were founded by white‐capped albatrosses.
Genetic population structure and mobility of two nectar‐feeding bats from Venezuelan deserts: inferences from mitochondrial DNA
Authors: Newton Lyndsay R. , Nassar Jafet M. , Fleming Theodore H.
Published: October 2003

Glossophaga longirostris and Leptonycteris curasoae are nectar‐feeding bats associated with arid zones in northern South America. Despite their close phylogenetic relationship, sympatric condition and niche similarities, morphological and ecological evidence suggest that these species differ in dispersal capabilities. Using mitochondrial DNA, we tested the hypothesis that these species exhibit different levels of population structure that are congruent with their particular movement capabilities. We sequenced a section of the control region of mtDNA for 41 G. longirostris and 42 L. curasoae from 11 zones in Venezuela. Population subdivision in G. longirostris (FST = 0.725) was considerably higher than in L. curasoae (FST = 0.167). L. curasoae individuals shared haplotypes at greater distances (812 km) than G. longirostris (592 km). Our results offer preliminary evidence for one of two possible scenarios, either greater mobility in L. curasoae or a higher degree of female philopatry in G. longirostris.
Functional effects of deleting the coiled‐coil motif in Escherichia coli elongation factor Ts
Authors: Karring Henrik , Björnsson Asgeir , Thirup Søren , Clark Brian F. C. , Knudsen Charlotte R.
Published: October 2003

Elongation factor Ts (EF‐Ts) is the guanine nucleotide‐exchange factor for elongation factor Tu (EF‐Tu) that is responsible for promoting the binding of aminoacyl‐tRNA to the mRNA‐programmed ribosome. The structure of the Escherichia coli EF‐Tu–EF‐Ts complex reveals a protruding antiparallel coiled‐coil motif in EF‐Ts, which is responsible for the dimerization of EF‐Ts in the crystal. In this study, the sequence encoding the coiled‐coil motif in EF‐Ts was deleted from the genome in Escherichia coli by gene replacement. The growth rate of the resulting mutant strain was 70–95% of that of the wild‐type strain, depending on the growth conditions used. The mutant strain sensed amino acid starvation and synthesized the nucleotides guanosine 5′‐diphosphate 3′‐diphosphate and guanosine 5′‐triphosphate 3′‐diphosphate at a lower cell density than the wild‐type strain. Deletion of the coiled‐coil motif only partially reduced the ability of EF‐Ts to stimulate the guanine nucleotide exchange in EF‐Tu. However, the concentration of guanine nucleotides (GDP and GTP) required to dissociate the mutant EF‐Tu–EF‐Ts complex was at least two orders of magnitude lower than that for the wild‐type complex. The results show that the coiled‐coil motif plays a significant role in the ability of EF‐Ts to compete with guanine nucleotides for the binding to EF‐Tu. The present results also indicate that the deletion alters the competition between EF‐Ts and kirromycin for the binding to EF‐Tu.
New concepts of cytokines in asthma: Is the Th2/Th1 paradigm out the window?
Authors: Prescott SL
Published: October 2003

Abstract:  Although asthma is clearly associated with a systemic propensity for allergic T helper type 2 (Th2) cell cytokine responses, independent local immune events appear to be responsible for the development of allergic airways inflammation. There is growing interest in how local immune networks interact with resident airway cell populations such as epithelial cells, which are now also recognized as key producers of cytokines, chemokines and growth factors. As well as their recognized role in airway remodelling, epithelial cells are now thought to have a role in initiating events. This review examines the role of cytokines produced by these and other cells in the development of asthma. It also highlights emerging concepts that the excessive and inappropriate immune responses seen in allergic disease may be related to dysfunction of various interleukin‐10 producing regulatory cell populations.
Medical staff's knowledge of pulse oximetry: A prospective survey conducted in a tertiary children's hospital
Authors: Teoh L , Epstein A , Williamson B , Morton J , Papadopoulos D , Teng A
Published: October 2003

Objectives:  To assess the knowledge of pulse oximetry of senior (SMO) and junior medical officers (JMO) in a tertiary paediatric hospital.

Methods:  A 16‐item multiple choice questionnaire was administered to SMO and JMO without prior notice or instruction in the area. The questions were completed voluntarily and anonymously, then proctored and collated by the principal investigator.

Results:  The mean test scores for SMO and JMO were 70 ± 15% and 65 ± 13%, respectively (P = 0.06). A significant negative correlation was found between the test scores and the years of paediatric experience with the SMO.

Conclusions:  The results of the survey showed there is an insufficiency of knowledge and understanding among medical staff concerning the principles, clinical applications and limitations of pulse oximetry. More emphasis needs to be placed on teaching these principles to ensure quality care for patients.
Early adolescent smoking and a web of personal and social disadvantage
Authors: Conwell LS , O'Callaghan MJ , Andersen MJ , Bor W , Najman JM , Williams GM
Published: October 2003

Objective:  To examine concurrent physical, educational, behavioural, social and family factors associated with cigarette smoking in adolescents at 14 years.

Methodology:  This study reports cross‐sectional data on 14‐year‐old adolescents and their mothers, drawn from a prospective cohort study commencing at the time of the first antenatal visit. At 14 years, 5247 adolescents completed questionnaires on current cigarette smoking. Adolescents and mothers completed health, psychological, school and social questionnaires relating to the youth. A total of 3864 adolescents were assessed physically, and undertook the Wide Range Achievement Test (WRAT) and Ravens Progressive Matrices Test.

Results:  Cigarette smoking at 14 years was associated with externalizing and internalizing behaviour problems, school suspension, contact with children's services and alcohol/illicit drug use. Apart from internalizing behaviour problems, these problems were more prevalent in boys. Poor school performance on maternal/adolescent reports was associated with increased smoking quantity for both genders, though WRAT scores were only decreased in male smokers. The Ravens Progressive Matrices Test scores were lower for boys with greater smoking quantity. The trend was less marked in girls. Body mass index and exercise frequency were not associated with cigarette smoking at 14 years, though girls who smoked had a higher reported prevalence of asthma. Parental smoking, marital conflict, maternal depression, lower income, and mothers aged in their teens and with a lower level of education at the time of this pregnancy were also positively associated with adolescent tobacco use.

Conclusion:  Findings of this study indicate that cigarette smoking, at this critical time of smoking initiation, is associated with a broad spectrum of personal and social disadvantage that needs to be considered in intervention strategies.
Serious lead poisoning in childhood: Still a problem after a century
Authors: Reith DM , O'Regan P , Bailey C , Acworth J
Published: October 2003

Objective:  To describe a series of patients with clinically significant lead poisoning.

Methodology:  A case series of nine patients with lead poisoning who required inpatient management, identified through a Clinical Toxicology Service.

Results:  Nine children presented with clinically significant lead poisoning. The median serum lead was 2.5 µmol/L (range 1.38−4.83). Eight of the children were exposed to lead‐based paint, with seven due to dust from sanded lead paint during house renovations. Serial blood determinations suggested re‐exposure in four of the patients, and in one of these patients the re‐exposure was from a different source of lead. Eight of the patients required chelation therapy.

Conclusions:  Serious lead poisoning continues to occur and there appears to be complacency regarding the hazard posed by lead paint in old houses.
Hepatic mesenchymal hamartoma
Authors: Yen J‐B , Kong M‐S , Lin J‐N
Published: October 2003

Abstract:  Hepatic mesenchymal hamartoma (HMH) is a rare liver tumour in childhood. It is believed to be a benign tumour with a good prognosis if the tumour is excised. Only a few cases with local relapse or metastasis have been reported. We reviewed 134 patients with space‐occupying liver lesions, from January 1990 to December 1999, and four patients with HMH were found. Abdominal mass and/or distension were the common initial presentations. Three of our four cases were diagnosed in the first year of life. The liver function tests and tumour markers were non‐specific. Case 1 underwent tumour enucleation and another three cases underwent tumour excision. One patient died. No tumour recurrence was noted in the surviving patients.
Current status of dialytic therapy in Korea
Authors: KIM Suk Young , JIN Dong Chan , BANG Byung Kee
Published: October 2003

SUMMARY:  The status of dialytic therapy in Korea at the end of 2001 was reported by the end‐stage renal disease (ESRD) registry committee of Korean Society of Nephrology, where data were collected through an internet on‐line registry program. The number of dialysis centres was 335 and the number of haemodialysis machines was 5529. The total number of patients with dialysis was 23 057 (haemodialysis 17 568, peritoneal dialysis 5489). Prevalence and incidence of dialysis patients were 477.5 and 96.4 patients per million population. The most common primary cause of end‐stage renal diseases was diabetic nephropathy (41.5%), hypertensive nephrosclerosis (15.4%), and chronic glomerulonephritis (13.6%). Eighty‐six percent of haemodialysis patients were on dialysis therapy three times a week, the mean urea reduction ratio was 66.7 ± 8.68% and mean Kt/V was 1.250 ± 0.292 in male patients; 1.526 ± 0.361 in female patients. The technical survival of haemodialysis in 5 years was 30.2% and peritoneal dialysis was 13.8%. The common complication of haemodialysis patients was hypertension (43.3%), gastrointestinal disease other than peptic ulcer (8.0%), congestive heart failure (7.6%), and of peritoneal dialysis patients were also hypertension (28.8%), congestive heart failure (5.0%), and peritonitis (4.8%). The most common causes of death were cardiac diseases (26.9%), vascular diseases, including cerebrovascular accidents (22.7%), and infection (17.8%).
Comparison of hematologic or biochemical parameters among elderly hospital patients, institution‐dwelling residents, and health check‐up examinees
Authors: Yamamoto Ryuichi , Asai Kanichi , Miura Satoru , Kimata Takaya , Ando Fujiko , Iguchi Akihisa
Published: October 2003

Background:  The purpose of the present paper was to examine the differences in the levels of hematological or biochemical parameters among elderly hospital patients, nursing home residents, and mass health check‐up recipients.

Methods:  One hundred and 44 geriatric inpatients (aged ≥ 65 years), 237 outpatients, 146 nursing home residents, 120 aged examinees from mass health check‐ups, and 512 younger health check‐up examinees (controls) were included in the present study. They were divided into five male and five female subgroups, respectively. The levels of hemoglobin (Hb), white blood cells (WBC), serum albumin (Alb), Ca, albumin‐corrected Ca, Na, creatinine (Cr), and total cholesterol (TC) were determined and compared.

Results:  There were significantly lower levels of Hb, Alb, Ca, Na, and TC in inpatients than in other groups in both sexes. In contrast, higher levels of WBC and Cr were found in inpatients. Among women there was no difference in the level of any parameter between nursing home residents, health check‐up examinees, and controls.

Conclusion:  The data indicate that the levels of these parameters are affected to a greater extent in inpatients, and that female nursing home residents and health check‐up examinees show values similar to those of controls.
Control of venous bleeding during dissection near the head of the pancreas
Authors: Samra Jaswinder S. , Smith Ross C.
Published: October 2003

Avulsion injury to portal vein tributaries can result in worrying haemorrhage during pancreatic gastric, and colonic resection. Attempts to control these avulsion injuries can result in extension of the tear into major portal vein tributaries. Pressure on the bleeding point tends to extend the laceration towards the portal vein, which bleeds torrentially when pressure is released for suturing. A technique is described to control the bleeding from these portal vein tributaries. This technique relies on adequate visualization and control of the torn ends of the portal vein tributaries thus enabling the surgeon to precisely suture the disrupted vessel without any collateral damage. This technique has been used on a number of occasions over the last decade with excellent results.
Thromboprophylaxis practice patterns in hip fracture surgery patients: experience in Perth, Western Australia
Authors: Wan Susan , Ting Jeannette , Olsen Amanda , Croser John , Eikelboom John W.
Published: October 2003

Background:  International guidelines recommend that all patients undergoing hip fracture surgery receive specific thromboprophylaxis. The purpose of the present study was to examine current thromboprophylaxis practice patterns in patients undergoing hip fracture surgery at Royal Perth Hospital.

Methods:  A total of 129 consecutive patients admitted to Royal Perth Hospital between 4 February and 21 July 2002 for surgical repair of a fractured neck of femur, was studied. The primary outcome was the frequency, type, and duration of thromboprophylaxis use during hospitalization.

Results:  Mean patient age was 79.4 ± 13.4 years and 69.8% (90/129) were female. Seventy‐four patients (57.8%; 95% confidence interval (CI): 48.8−66.8%) received specific thromboprophylaxis during hospitalization, including 50 patients (39.1%; 95%CI: 30.6−48.1%) who received pharmacological prophylaxis only, three (2.3%; 95%CI: 0.5−6.7%) who received mechanical prophylaxis only, and 21 (16.4%; 95%CI: 10.5−24.0%) who received both mechanical and pharmacological prophylaxis. Of those receiving pharmacological prophylaxis, 35 (49.3%; 95%CI: 37.2−61.4%) received low‐molecular‐weight heparin, 26 (36.6%; 95%CI: 25.5−48.9%) received low‐dose unfractionated heparin, eight (11.3%; 95%CI: 5.0−21.0%) received warfarin, 35 (49.3%; 95%CI: 37.2−61.8%) received aspirin or clopidogrel, and 27 (38.0%; 95% CI: 26.8−50.3%) received combined anticoagulant and antiplatelet prophylaxis. The median duration of mechanical prophylaxis was 8 days (range: 6−12 days) and that of pharmacological prophylaxis was 12 days (range: 6−26 days). When the 32 patients already taking aspirin or warfarin at the time of admission were excluded, only 45 (46.9%; 95%CI: 36.6−57.3%) of the remaining 96 patients received specific thromboprophylaxis.

Conclusion:  Specific thromboprophylaxis remains under‐utilized in patients undergoing surgery for hip fracture at Royal Perth Hospital. These data should prompt the implementation of effective strategies to improve thromboprophylaxis practice patterns in high‐risk orthopaedic patients.
Chemokines and the inflammatory response following cardiopulmonary bypass – a new target for therapeutic intervention? – a review
Authors: Ben‐Abraham Ron , Weinbroum Avi A. , Dekel Benjamin , Paret Gideon
Published: October 2003

This 10‐year Medline search of English‐language articles describing experimental and clinical studies on chemokines, cardiopulmonary bypass (CPB) and systemic or multiorgan failure revealed that chemokines are significantly involved in the pathogenesis of post‐CPB syndrome. The post‐CPB inflammatory response depends upon recruitment and activation of inflammatory cells. Leucocyte recruitment is a well‐orchestrated process that involves several protein families, including pro‐inflammatory cytokines, adhesion molecules and chemokines. Current anti‐inflammatory therapies mostly act on the cells that have already been recruited. A more efficient therapy might be the prevention of excessive recruitment of particular leucocyte populations by antagonizing chemokine receptors which might act upstream of the current anti‐inflammatory agents. The chemokines, which are a cytokine subfamily of chemotactic cytokines, participate in recognizing, recruiting, removing and repairing inflammation. As chemokines target specific leucocyte subsets, antagonism of a single chemokine ligand or receptor would be expected to have a circumscribed effect, thereby endowing the antagonist with a limited side‐effect profile. Chemokines should be considered as possible targets for therapeutic intervention.
Remifentanil vs alfentanil in the total intravenous anaesthesia for paediatric abdominal surgery
Authors: Ganidagli Suleyman , Cengiz Mustafa , Baysal Zeynep
Published: October 2003

Summary Backgrounds: Our aim was to investigate whether total intravenous anaesthesia (TIVA) with remifentanil and alfentanil would ensure appropriate analgesia and recovery conditions in anaesthesia for children undergoing abdominal surgery.

Methods: Sixty children, scheduled for abdominal operations were randomized to receive, in a double‐blind manner, either remifentanil (loading dose 1 μg·kg−1; maintenance infusion, 0.25 μg·kg−1 min−1) or alfentanil (loading dose 50 μg·kg−1; maintenance infusion, 1 μg·kg−1 min−1) as the analgesic component of TIVA. They were combined with propofol (loading dose, 2 mg·kg−1; step 1 maintenance infusion, 10 mg·kg−1 h−1; step 2 maintenance infusion, 8 mg·kg−1 h−1; step 3 maintenance infusion, 6 mg·kg−1 h−1) neuromuscular blockade was with mivacurium. Dose changes of the drugs, the times from cessation of anaesthesia to extubation, verbal responses, recovery of ventilation, orientation, and qualification for discharge from the postanaesthetic care unit (PACU) were recorded.

Results: Demographics, duration of surgery and anaesthesia were similar between the two groups. Times to extubation and stay in the PACU were significantly shorter in the remifentanil group compared with the alfentanil group. Quality of emergence (QE) from anaesthesia scale scores were higher in the remifentanil group compared with the alfentanil group.

Conclusions: Remifentanil provides a more rapid recovery and adequate postoperative analgesia after TIVA for paediatric abdominal surgery, compared with alfentanil.
The Air‐Bubble Method of Locking Central‐Vein Catheters with Acidified, Concentrated Sodium Chloride as a Bactericidal Agent: In Vitro Studies
Authors: Moore Harold L. , Twardowski Zbylut J.
Published: October 2003

Background:  Soft, cuffed indwelling catheters are used for hemodialysis access and intravenous infusions. The majority of these catheters are removed as a result of infection caused by contamination of the catheter hub during the connection/disconnection procedures. To prevent clot formation in the lumen, these catheters are routinely “locked” with heparin or some other anticoagulant. None of the anticoagulants commonly used as locking solutions demonstrates any significant bactericidal properties. The primary goal of this study was the development of a catheter locking method that retains anticoagulant properties at the catheter tip and bactericidal properties at the catheter hub. The second goal was to find a solution that possesses excellent bactericidal properties but is not detrimental in the event of injection into the patient's blood stream. The bactericidal properties of acidified, concentrated saline (ACS) were compared to concentrated trisodium citrate and to commonly used bactericidal agents such as povidone iodine, sodium hypochlorite, and chlorhexidine.

Methods:  In preliminary studies, the rate of diffusion of solutes was measured in glass tubes. In another set of experiments, the mixing of two solutions (anticoagulant and bactericide) separated by an air bubble (“air‐bubble method”) was observed in stationary and moving systems. The final series of studies compared the bactericidal properties of ACS to other bactericidal solutions mentioned above.

Results:  The solutions diffused swiftly in the glass tubes, and by the third day, both solutions were mixed. The air‐bubble method prevented mixing in both stationary and moving systems. The bactericidal properties of ACS were superior to all other tested solutions.

Conclusions:  The proposed method of catheter locking with anticoagulant at the catheter tip and ACS at the catheter hub separated by an air bubble is a promising technique and clinical studies are warranted.
A Protocol for Isolating Putative Helicobacter pylori from Fecal Specimens and Genotyping using vacA Alleles
Authors: Liang Shuwen , Redlinger Thomas
Published: October 2003

Background.   This study outlines steps for isolating and culturing Helicobacter pylori from freshly voided fecal specimens and genotyping isolates for vacA alleles.

Materials and methods.   A family with four H. pylori‐infected members participated in this pilot study. Criterion for participation was a positive test for H. pylori by the urea breath test. Fecal specimens from children were taken from a freshly soiled diaper, placed in cold buffer, and prepared for culture in less than 2 hours. Culturing of H. pylori utilized selective culture media and isolates were screened for negative Gram stain, positive catalase and oxidase tests, and positive H. pylori 16S ribosomal RNA polymerase chain reaction (PCR). Strain types were determined by vacA genotyping.

Results.   The isolation procedure is relatively simple, although 5–7 days are required for H. pylori culturing. Isolation and purification of DNA eliminated PCR inhibitors and resulted in reliable analyses. All four family members were infected with the same H. pylori strain with a genotype of vacA s1a/m2.

Conclusion.   This research lays the foundation for developing a routine and direct noninvasive method to detect the presence of H. pylori in fecal specimens. It is especially convenient for diagnosing children and infants, as samples can be obtained from soiled diapers. Culturing H. pylori from fecal samples in certain cases is important for antibiotic resistant studies prior to treating infected patients and for strain genotyping in epidemiological studies to determine transmission.
Use of Metarhizium flavoviride for control of Zonocerus variegatus: A model, linking dispersal and secondary infection from the spray residue with mortality in caged field samples
Authors: Langewald J. , Thomas M.B. , Douro‐Kpindou O.‐K. , Lomer C.J.
Published: October 2003

A field trial was conducted using an oil formulation of the entomopathogenic fungus, Metarhizium flavoviride Gams & Rozyspal (Deuteromycotina: Hyphomycetes), to control the variegated grasshopper, Zonocerus variegatus L. (Orthoptera: Pyrgomorphidae). The influence of dispersal and secondary pick‐up from the spray residue on mortality was assessed by sampling insects from the treated plots at intervals and monitoring disease levels during subsequent incubation in the laboratory. The cumulative mortality curves showed the pathogen to be highly effective, even in samples taken 8 days after spraying. A model was developed to link the influence of mortality, incubation, secondary pick‐up of spores and insect dispersal, on the shape of these cumulative mortality curves. The model proved useful for data received from an experiment using small plot sizes, where insect dispersal is a big problem. The spray residue had an important influence on overall insect mortality. The model also indicated a difference in speed of kill between field and laboratory samples, suggesting an incubation delay in the field.
Oviposition behavior and reproductive success of the cerambycid Acanthocinus aedilis in the presence and absence of the bark beetle Tomicus piniperda
Authors: Schroeder L.M.
Published: October 2003

The influence of Tomicus piniperda (L.)(Col.:Scolytidae) attacks on Acanthocinus aedilis (L.)(Col.:Cerambycidae) (1) oviposition behavior, (2) breeding material preference and (3) reproductive success was investigated in caged pine bolts with and without egg galleries of T. piniperda. In addition, A. aedilis oviposition behavior was studied in the field. In the presence of T. piniperda attacks most A. aedilis eggs were laid through the entrance holes of the bark beetle egg galleries. In the absence of bark beetle attacks most A. aedilis eggs were laid at places where the outer bark had been damaged and the phloem was exposed. In cages, A. aedilis preferred to oviposit in bolts with bark beetle attacks. Thus, A. aedilis oviposited in all 17 of bark beetle attacked bolts but in only four of nine bolts without T. piniperda attacks. Neither the number of A. aedilis offspring nor the body size of emerging adults differed significantly between bolts attacked by bark beetles and unattacked bolts. Nor was there any significant relationship between the density of bark beetle egg galleries and the production of A. aedilis offspring.
Genetics of the ability of Phyllotreta nemorum larvae to survive in an atypical host plant, Barbarea vulgaris ssp. arcuata
Authors: Nielsen Jens Kvist
Published: October 2003

A polymorphism in host plant exploitation has been discovered in the flea beetle, Phyllotreta nemorum L. (Coleoptera: Chrysomelidae: Alticinae) where one resistant population is able to use Barbarea vulgaris R.Br. ssp. arcuata (Opiz.) Simkovics (Brassicaceae) as a host plant while a susceptible population is not. Crosses (F1, F2, and backcrosses) between the two flea beetle populations were made, and survival of the progeny on B. v. ssp. arcuata was measured. The ability of P. nemorum larvae to survive in this plant species depended on the presence of major, dominant genes (R‐genes). The two most abundant R‐genes in the resistant flea beetle population were X‐ and Y‐linked, respectively. The use of B. v. ssp. arcuata as a natural host plant by the resistant population of P. nemorum seems to be an extension of the host plant range of the species. The role of sex‐linked genes in the evolution of host range is discussed.
The effects of thermal acclimation on immature mortality in the Queensland fruit fly Bactrocera tryoni and the light brown apple moth Epiphyas postvittana at a lethal temperature
Authors: Beckett S. J. , Evans D. E.
Published: October 2003

Mortality data for non‐acclimated and acclimated 3rd instar larvae and mid‐term eggs of Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) were obtained after immersing in hot water at 46 °C. Acclimation consisted of holding the larvae and eggs at 35 °C for 20 and 11 h respectively just prior to heat‐treatment. The median lethal time (LT50) for acclimated larvae was found to be 6.9 min compared to 2.5 min for non‐acclimated larvae. LT99.999 for acclimated larvae was 20.9 min compared to 8.7 min for non‐acclimated larvae. LT50 for acclimated eggs was 5.0 min compared to 2.4 min for non‐acclimated eggs. LT99.999 for acclimated eggs was 26.0 min compared to 6.6 min for non‐acclimated eggs. For 3rd instar larvae, most acclimation effect on mortality had occurred by 8 h. A notable residual response was present 20 h after acclimation had occurred, reducing mortality at 46 °C for 4.5 min by roughly 25%. Mortality data at 46 °C were also obtained for non‐acclimated and acclimated late instar larvae of Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae). With this species, LT50 for acclimated larvae was 2.5 min compared to 1.1 min for non‐acclimated larvae. LT99.999 for acclimated larvae was 9.5 min compared to 4.6 min for non‐acclimated larvae.