bluuebunny/crossref_metadata_2025 huggingface dataset:
A prokaryotic dnaA sequence in Drosophila melanogasten Wolbachia infection and cytoplasmic incompatibility among laboratory strains
Authors: Bourtzis K. , Nirgianaki A. , Onyango P. , Savakis C.
Published: December 2007

Using oligonucleotide primers derived from the aligned polypeptide sequences of several prokaryotic dnaA genes, we amplified from Drosophila melano‐gaster DNA a 557 bp fragment containing a single open reading frame. The predicted peptide sequence shows a significant similarity to previously characterized protein sequences that are encoded by the dnaA genes of several prokaryotes. The dnaA sequences are also detectable by PCR in DNA from Drosophila simulans and Nasonia vitripennis flies which are infected by a symbiotic bacterium assigned to the type species Wolbachia pipientis. A tetracycline treatment that eradicates bacterial parasites from insects, abolishes the dnaA sequences from Drosophila and Nasonia DNA. In addition, dnaA‐positive Drosophila melano‐gaster contain numerous rod‐shaped bacteria in embryos, which are abolished in subsequent generations after treatment with tetracycline. Combined with phylogenetic analysis of DnaA and 16S rRNA sequences, these results show that the dnaA cognate comes from Wolbachia. A survey of Drosophila stocks using PCR amplification of dnaA and 16S rRNA sequences showed that Wolbachia is widely spread among D. melanogaster laboratory strains but absent from several established strains of the Mediterranean fruit fly Ceratitis capitata. Evidence is also presented that presence of the bacterium can cause partial cytoplasmic incompatibility between infected and non‐infected D, melanogaster strains.
Analysis of the Anopheles gambiae genome using RAPD markers
Authors: Favia G. , Dimopouios G. , Louis C.
Published: December 2007

RAPD analysis technique is used as a rapid and reliable tool for genome analysis in the malaria vector Anopheles gambiae. Using more than eighty different commercially available primers we identified more than sixty different DNA segments that were differentially amplified in different strains of An. gambiae s.s. and An. arabiensis. An estimate of the cytogenetic position of these markers is provided by their hybridization to divisional dot‐blot filters. Potentially useful RAPD markers can be cytogenetically mapped with more precision by in situ hybridization and, as they segregate as dominant markers in a Mendelian fashion, they can also be genetically mapped relative to other genes or rearrangements. Finally, we identified markers for their potential use in the identification of different mosquito strains.
Molecular analysis of ribosomal DNA from the aphid Amphorophora idaei and an associated fungal organism
Authors: Fenton B. , Birch A. N. E. , Malloch G. , Woodford J. A. T. , Gonzalez C.
Published: December 2007

The ribosomal DNA cistron from the large raspberry aphid, Amphorophora idaei (Hemiptera: Aphididae), has been mapped by restriction analysis. The results showed that the map of A. idaeiwas similar to those of the previously characterized aphids Schizaphis grami‐num and Acyrthosiphon pisum. An extra Bglti site was found in some of the ribosomal DNA intergenic spacer repeats in A. idaei. Using in‐situ hybridization to aphid mitotic chromosomes it was demonstrated that probes derived from this region mapped to the pair of X chromosomes and it was therefore aphid in origin. Polymerase chain reaction using conserved rDNA primers also detected significant amounts of a fungal genome in the DNA samples. Microscopic investigation showed that the external surface of A. idaei harboured fungal propagules, hyphae and yeast‐like organisms.
cDNA structure and characterization of a kinesin‐like protein from the silkworm Bombyx mori
Authors: Okano K. , Takada N. , Kobayashi M. , Maekawa H.
Published: December 2007

We have isolated a 1224 bp cDNA clone from a Bombyx mori embryonic cDNA library which contains sequences homologous to the kinesin‐like protein gene, ncd, which is required for distribution of chromosomes at meiosis in Drosophila melanogaster females. This clone includes both a microtubule motor and the ATP‐binding domains found in kinesin‐like proteins. The motor domain is classified in the group of the BimC and cut7, which have a role in spindle formation during mitosis of Aspergillus nidulans and Schizosaccharomyces pombe, respectively. However, the location of the domain at the carboxy terminus is not common in this family, except for ncd and KAR3.
Complete base sequence for the mitochondrial large subunit ribosomal RNA of the gypsy moth Lymantha dispar(L.)
Authors: Davis R. E. , Kelly T. J. , Masler E. P. , Thyagaraja B. S. , Rote C. A. , Imberski R. B.
Published: December 2007

A 1355 bp sequence (accession number L32141) isolated from a gypsy moth (Lymantria dispar) cDNA library showed 68–74% sequence identity to mitochondrial large subunit ribosomal RNA (mt IrRNA) sequences of Locusta migratoria, Apis mellifera, Aedes albopictus, Anopheles gambiae and two Dros‐ophila species. A comparison of the primary sequences of the mt IrRNAs from the above insects in four orders and from Esherichia coli demonstrated regions of conservation which presumably correspond to regions of functional and/or structural homology. A secondary structure for the gypsy moth mt IrRNA sequence was derived based on the proposed secondary structures of Drosophila yakubaand Aedes albopictus mt IrRNAs (Gutell & Fox, Nucleic Acid Res 16 (Suppl.), r175‐r269, 1988). This sequence was found to hybridize to about 10–15% of the clones in several (eleven) gypsy moth cDNA libraries.
An analysis of secondary spread by putative clones of Sitobion avenae within a Hampshire wheat field using the multilocus (GATA)4 probe
Authors: Barro P. J. De , Sherratt T. N. , Carvalho G. R. , Nicol D. , Iyengar A. , Maclean N.
Published: December 2007

Grain aphids (Sitobion avenae (F.)) were collected from forty‐four wheat ears in a Hampshire field at three times during the growing season. On each occasion, individual aphids were profiled using the multilocus (GATA)4 probe. During the full head emergence and full anthesis growth stages of wheat, each ear generally supported a genetically distinguishable aphid colony which consisted of genetically indistinguishable individuals (putative clones). This information strongly suggests that individual ears were colonized by single immigration events. By the late milky ripe stage, most ears supported two or more such clones. The total number of clones declined and the spatial separation of identical clones increased markedly over the duration of the study, which strongly suggests that secondary spread rather than increased immigration was responsible for the increased clonal diversity of ears. In addition, the profiles of individual S. avenae became more alike as the season progressed and samples became dominated by particular clones indicating either differential survival or reproduction among clones.
Sequence analysis of the D1 and D2 regions of 28S rDNA in the hornet (Vespa crabro) (Hymenoptera, Vespinae)
Authors: Schmitz J. , Moritz R. F. A.
Published: December 2007

The two variable domains D1 and D2 near the 5 end of the 28S ribosomal RNA gene (large subunit rRNA) have been sequenced for Vespa crabro. The sequence was aligned to corresponding rDNA regions of the wasp species Nasonia vitripennis, Melittobia digitata and the fruit fly Drosophila melanogaster. We analysed the nucleotide composition and sequence similarity for the different regions of the investigated sequences and present the inferred secondary structure of Vespa crabro.
Why do pupating insects lack an activity for the repair of uracil‐containing DNA? One explanation involves apoptosis
Authors: Deutsch W. A.
Published: December 2007

Although uracil‐DNA glycosylases were at one time considered to be ubiquitous in nature, this DNA repair activity is notably absent in Drosophila melanogaster and other pupating insects. On the other hand, a nuclease has been identified in Drosophila that is specific for uracil‐containing DNA, but curiously the expression of this activity is restricted to late larval stages of development. Since the nuclease activity is only detected near the time of histolysation, we began questioning the possible role uracil might play in the events associated with the eventual DNA degradation that is involved in the metamorphotic process. The results of these studies have provided us with a molecular model for pupating insects that contains all the necessary elements to program cells for their ultimate death, and in so doing, shows why uracil‐DNA glycosylases would be incompatible with our proposed pathway for apoptosis.
Identification of a mariner element from the tsetse fly, Glossina palpalis palpalis
Authors: Blanchetot A. , Gooding R. H.
Published: December 2007

In the present study, the polymerase chain reaction was used initially to demonstrate the presence of mariner sequences in seven species/subspecies of tsetse flies. ONA hybridization experiments show mariner sequences to be dispersed within the tsetse genome and that there are large variations in copy numbers among the various taxa. A genomic library was used to isolate and characterize a full‐length mariner element from G. p. palpalis. The results indicate that this element is 1257 bp in length, flanked by two 32 bp inverted repeats differing at only one position, and belongs to the mellifera subfamily. The nucleotide sequence that is translated into a reading frame of 337 amino acids requires the introduction of two frame shifts and one stop codon to maximize sequence homology with a mariner element from Drosophila erecta. Based on this evidence, we conclude that the G. p. palpalis mariner element clearly represents a non‐functional transposable element and that the protein product is not an active transposase.
Mosquito sensitivity to a scorpion neurotoxin expressed using an infectious Sindbis virus vector
Authors: Higgs S. , Olson K. E. , Klimowski L. , Powers A. M. , Carlson J. O. , Possee R. D. , Beaty B. J.
Published: December 2007

The scorpion, Androctonus australis Hector, produces an insect‐specific toxin (AaHIT) encoded by the Scotox gene. To assess the toxicity of AaHIT for mosquitoes, we have taken a novel approach to express the Scotox gene in vivo. We have engineered a double subgenomic Sindbis (dsSIN) virus that contains the Scotox gene in the viral genome and intrathoracically inoculated the virus (TE/3'2J/Scotox) into mosquitoes (Aedes aegypti, Ae. triseriatus and Culex pipiens), houseflies (Musca domestica) and ticks (Dermacentor andersoni). Mosquitoes, which normally show no pathologic effects from Sindbis (SIN) virus infections, died 1–5 days after infection with TE/3'2J/Scotox virus. Neither flies nor ticks were killed. The mosquitocidal action of AaHIT in mosquitoes makes AaHIT a potential candidate for inclusion in molecular‐based methods of mosquito control. The expression of an arthropod gene in vivo demonstrates the utility of dsSIN expression vectors for future use to examine and potentially disrupt endogenous gene functions in mosquitoes.
Microsatellite DNA and isozyme variability in a West African population of Anopheles gambiae
Authors: Lanzaro G. C. , Zheng L. , Toure Y. T. , Traore S. F. , Kafatos F. C. , Vernick K. D.
Published: December 2007

Microsatellites are defined as tracts of tandemly repeated short DNA sequences. Polymorphisms in this class of DNA are currently being used to generate a genetic map of the mosquito Anopheles gambiae. In the present study we explore the potential of microsatellites as a tool for studying the genetic structure of natural populations of this malaria vector. Genetic polymorphism at twenty enzyme coding gene loci and eleven microsatellite DNA loci was surveyed in a population of An. gambiae from Mali, West Africa. All of the microsatellite loci surveyed were polymorphic, as compared to 40% of the isozyme loci. The mean heterozygosity for the isozyme loci was only 0.097 (±0.0035), but for the microsatellite loci it was 0.732 (±0.060). The pattern of variability was very different between isozymes and microsatellites. Typically, at an isozyme locus a single allele occurred at a frequency ≥0.75, whereas at microsatellite loci the most common allele had a frequency <0.50. We conclude that micro‐satellites provide a rich source of genetic polymorphisms for the study of the population genetics of An. gambiae and are in many ways superior to isozymes for this purpose. We discuss the potential for utilizing genetically mapped microsatellite loci to explore the effect of chromosomal inversions on the distribution of genetic polymorphisms in An. gambiae.
Organization and expression of the hemolin gene, a member of the immunoglobulin superfamily in an insect, Manduca sexta
Authors: Wang Y. , Willott E. , Kanost M. R.
Published: December 2007

Hemolin is a protein from the immunoglobulin (Ig) superfamily found so far in the haemolymph of two lepidopteran insect species, Hyalophora cecropia and Manduca sexta. Injection of bacteria into these insects induces the expression of hemolin. We have isolated the hemolin gene from M. sexta and determined its DNA sequence and transcription start site. The hemolin gene is 3127 bp long and contains six exons. The only correspondence between exons and the four Ig domains of hemolin is in domain 4, which is encoded by exon 6. Southern blot analysis indicates that there is one copy of the hemolin gene in the M. sexta genome. Analysis of the 5'‐flanking sequence of the hemolin gene resulted in identification of potential regulatory sequences. Hemolin mRNA accumulated in haemocytes, as well as fat body, in response to injection of larvae with bacteria. Hemolin was detected by immunocytochemistry in only one of the five morphological haemocyte types in M. sexta, the granular cells.
CYP6B3: a second furanocoumarin‐inducible cytochrome P450 expressed in Papilio polyxenes
Authors: Hung Chien‐Fu , Harrison T. L. , Berenbaum M. R. , Schuler M. A.
Published: December 2007

Cytochrome P450 monooxygenases in the larvae of Papilio polyxenes (black swallowtail) (Lepidoptera: Papilionidae) are capable of detoxifying linear and angular furanocoumarins found in their host plants. The CYP6B1 locus, which is transcriptionally induced in these larvae in response to xanthotoxin, encodes a P450 that principally metabolizes linear furanocoumarins such as xanthotoxin and bergapten. We have now cloned CYP6B3 cDNA derived from a second locus that is evolutionarily related to the CYP6B1 locus. Reverse transcription‐PCR Southern analyses have demonstrated that CYP6B3 transcripts are expressed in response to a wider range of linear and angular furanocoumarins but at lower abundance than CYP6B1 transcripts. Whereas CYP6B1 transcripts are expressed at a low detectable level in uninduced control larvae and at high levels in xanthotoxin‐induced larvae, CYP6B3 transcripts are nearly undetectable in control larvae and are highly induced by xanthotoxin and bergapten (linear furanocoumarins) as well as by angelicin and sphondin (angular furanocoumarins). The fact that these two CYP6B loci are differentially regulated by these four furanocoumarins indicates that P. polyxenes has adapted to the presence of the wide range of furanocoumarins in its host plants by diversifying its P450 isozyme structures and its furanocoumarin‐responsive regulatory cascades.
Toward a physical map of Aedes aegypti
Authors: Brown S. E. , Menninger J. , Difillipantonio M. , Beaty B. J. , Ward D. C. , Knudson D. L.
Published: December 2007

Labelled recombinant cosmids were used as in situ hybridization probes to Aedes aegypti metaphase chromosomes. The cosmid probes yielded paired signals, one on each arm of sister chromatids, and they were ordered along the three chromosomes. In total, thirty‐seven different probes were mapped to the three chromosomes of Ae. aegypti (2n = 6): twenty‐eight to chromosome 1, six to chromosome 2, and six to chromosome 3. These results represent an initial stage in the generation of a physical map of the Ae. aegypti genome.
Amplification of complete insect mitochondrial genome in two easy pieces
Authors: Roehrdanz R. L.
Published: December 2007

The entire insect mitochondrial genome has been amplified in just two PCR reactions. ‘Universal’ insect primers and techniques to optimize amplification of long PCR products were used to obtain segments of the mitochondrial genomes of Helicoverpa zea and Heliothis virescens (Lepidoptera) ranging in size from 3.7 kb to 14 kb or about 25% to over 85% of a typical 16 kb mtDNA. Overlapping pairs of fragments contain the complete mtDNA sequence.
Replication and expression of a recombinant Sindbis virus in mosquitoes
Authors: Rayms‐Keller A. , Powers A. M. , Higgs S. , Olson K. E. , Kamrud K. I. , Carlson J. O. , Beaty B. J.
Published: December 2007

A recombinant Sindbis virus, TE/3'2J/ANTI‐S, containing LaCrosse virus small segment cDNA in antisense orientation, was inoculated into Aedes triseriatus mosquitoes. Virus replication and LAC‐ANTI‐S RNA expression were analysed temporally and spatially. TE/3'2J/ANTI‐S virus titre peaked at 5.0 log10 TCID50 in heads 6–9 days post infection (p.i.) and decreased to 3.4 log10 TCID50 by 37 days p.i. Salivary glands contained 4.4 log10 TCID50 of virus 6 days p.i.; titres were lower in other organs. LAC‐ANTI‐S RNA levels paralleled virus titre. SIN E1 antigen was detected in many mosquito organ systems, but in specific cells and tissues of some organs. TE/3'2J/ANTI‐S virus exhibited different cellular tropisms in salivary glands of Aedes and Culex mosquitoes.
Drosophila melanogaster mitochondrial DNA: completion of the nucleotide sequence and evolutionary comparisons
Authors: Lewis O. L. , Farr C. L. , Kaguni L. S.
Published: December 2007

The nucleotide sequence of the regions flanking the A + T region of Drosophila melanogaster mitochondrial DNA (mtDNA) has been determined. Included are the genes encoding the transfer RNAs for valine, isoleucine, glutamine and methionine, the small ribosomal RNA and the 5'‐coding sequences of the large ribosomal RNA and NADH dehydrogenase subunit II. This completes the nucleotide sequence of the D. melanogaster mitochondrial genome. The circular mtDNA of D. melanogaster varies in size among different populations largely due to length differences in the control region (Fauron & Wolstenholme, 1976; Fauron & Wolstenholme, 1980a, b); the mtDNA region we have sequenced, combined with those sequenced by others, yields a composite genome that is 19,517 bp in length as compared to 16,019 bp for the mtDNA of D. yakuba. D. melanogaster mtDNA exhibits an extreme bias in base composition; it comprises 82.2% deoxyadenylate and thymidylate residues as compared to 78.6% in D. yakuba mtDNA. All genes encoded in the mtDNA of both species are in identical locations and orientations. Nucleotide substitution analysis reveals that tRNA and rRNA genes evolve at less than half the rate of protein coding genes.
Analysis of mosquito genome structure using graphical genotyping
Authors: Severson D. W. , Kassner V. A.
Published: December 2007

Restriction fragment length polymorphism (RFLP) markers provide effective tools for establishing the genotype at many loci for individual mosquitoes. RFLP genotypes can be organized to provide information concerning parental origin or the allelic configuration of various chromosome segments. Whole genome genotypic information for individuals can be represented in a simple graphic format, termed graphical genotyping. In this study, RFLP markers were used to demonstrate the utility of using graphical genotyping to easily and quickly evaluate the entire genome of the mosquito Aedes aegypti. Two substrains selected for susceptibility and refractoriness, from a strain highly susceptible to the filarial worm parasite Brugia malayi, were compared. Graphical genotyping provided a mechanism to rapidly evaluate genome structure both within and between the two substrains with a simple visual analysis. This information was used in related studies to identify a new locus influencing B. malayi susceptibility in A. aegypti. Graphical genotyping also provided perspectives on some features of genome structure in A. aegypti. It suggested the presence and location of a genetic lethal on chromosome 3 and possible inversion polymorphisms associated with each of the three A. aegypti chromosomes.
Comparison of preservation techniques for DNA extraction from hymenopterous insects
Authors: Dillon N. , Austin A. D. , Bartowsky E.
Published: December 2007

Two species of parasitic wasp, Venturia canescens and Leptomastix dactylopii, were killed and preserved by various methods used for Hymenoptera and in mass‐collecting devices. Total genomic DNA was subsequently extracted and a 524 bp fragment of the mitochondrial 16s ribosomal RNA gene amplified by PCR. Results for these techniques were compared with that for fresh material and museum specimens. Material from ‐80°C, 100% ethanol, air‐drying in a desiccator, and critical‐point dried from alcohol all yielded good results after short and long‐term storage, as did specimens from ethylene glycol but not formalin (the latter two being commonly used in pitfall and flight intercept traps). Specimens killed in ethyl acetate vapour and air‐dried yielded very degraded DNA which did not successfully PCR. The use of this killing agent is a likely reason for previous reports of inconsistent results obtained from museum specimens, and the now widespread use of critical‐point drying of wasps and other insects from alcohol is advocated as a potential source of DNA from rare taxa.
Aedes aegypti midgut early trypsin is post‐transcriptionally regulated by blood feeding
Authors: Noriega F. G. , Pennington J. E. , Barillas‐Mury C. , Wang X. Y. , Wells M. A.
Published: December 2007

Early trypsin is a female‐specific protease present in the Aedes aegypti midgut during the first hours after ingestion of a blood meal. Early trypsin gene expression was studied by Northern blot analysis. The early trypsin mRNA, absent in larvae, pupae and newly emerged females, reaches detectable levels at 24 h post‐emergence and attains a maximum level at an adult age of 4–7 days. After the first week there is a decrease in the steady‐state level of the transcript, but it remains readily detectable for up to a month after emergence. Despite the high levels of early trypsin mRNA present in the midgut of the unfed female, translation of the early trypsin mRNA occurs only after a blood or a protein meal. Early trypsin mRNA levels rapidly decrease during the first 24 h after feeding, but the steady‐state level of the transcript rises again at the end of the blood digestion cycle (60 h), as the mosquito prepares for a second blood meal.
Isolation and characterization of three serine protease genes in the mosquito Anopheles gambiae
Authors: Sldén‐Kiamos I. , Skavdis G. , Rubio J. , Papagiannakis G. , Louis C.
Published: December 2007

Three genes encoding serine proteases (SpGA, Sp6T and Sp8T) were isolated from the malaria mosquito An, gambiae. The proteins that are conceptually translated from these genes contain all amino acids that have been described for this class of proteolytic enzymes, namely the His, Asp and Ser residues at the active site, and the six cysteine residues that form the three disulphide bridges in invertebrate serine proteases. The genes are expressed at low levels and the transcripts were detected only by PCR. Analysis of the nucleotide sequences of the three genes and their pattern of expression indicate that none of the genes code for digestive enzymes, but rather that the proteins have features of the tethered type of serine proteases.
Precise limitation of concerted evolution to ORFs in mosquito Hsp82 genes
Authors: Benedict M. Q. , Levine B. J. , Ke Z. X. , Cockburn A. F. , Seawright J. A.
Published: December 2007

Two Hsp82 genes were isolated from the malaria vector Anopheles albimanus in a single lambda phage clone. The two genes are in a head‐to‐head arrangement separated by approx. 0.9 kbp. Northern hybridizations and 5' RACE demonstrate that both genes are transcribed, have moderate levels of constitutive transcription, and are also heat‐inducible with maximum transcript accumulation occurring after 40°C heat shocks. Both genes have typical heat‐shock promoters and conserved intron boundaries in the untranslated leaders. The open reading frames are 99.6% identical differing in only nine silent nucleotide positions in the 2166 bp ORFs. However, precisely outside the ORFs, the flanking DNA of the two genes shows no evidence of common derivation. The high degree of identity between the two ORFs appears to be a result of gene conversion occurring by a process similar to that previously suspected in the A. albimanus Hsp70 genes and several D. melanogaster genes arranged as palindromes. This process probably involves a stem‐loop intermediate and is restricted in extent by flanking sequence divergence. These Hsp82 genes clearly demonstrate the extreme precision with which gene conversion can lead to proteincoding‐region homogeneity yet allow flanking DNA divergence.
Phylogeny of fourteen Culex mosquito species, including the Culex pipiens complex, inferred from the internal transcribed spacers of ribosomal DNA
Authors: Miller B. R. , Crabtree M. B. , Savage H. M.
Published: December 2007

Ribosomal DNA sequence divergence in the internal transcribed spacer regions (ITS‐1 and ITS‐2) was examined for fourteen species and four subgenera (sixty‐two clones) in the mosquito genus Culex (Diptera: Culicidae). A neighbour‐joining tree produced with Kimura 2‐parameter distances showed that each of the four subgenera was monophyletic at confidence probabilities of 70–99%. Culex (Lutzia) formed the sister group of Cx. (Culex). Two major clades, a Cx. pipiens complex‐Cx. torrentium assemblage and a Cx. restuans‐Cx, salinarius‐cx. erythrothorax assemblage, formed monophyletic groups. Cx. torrentium was closely related to members of the Cx, pipiens complex. Phylogenetic analysis of ITS‐1 and ITS‐2 sequences from members of the Cx. pipiens complex separated populations from northern latitudes and southern latitudes, but did not support the traditional taxa as monophyletic units.
Mosquito dopa decarboxylase cDNA characterization and blood‐meal‐induced ovarian expression
Authors: Ferdlg M. T. , Li J. , Severson D. W. , Christensen B. M.
Published: December 2007

Dopa decarboxylase (DDC) functions in insect cate‐cholamine biochemistry to produce materials essential for cross‐linking reactions that result in tanning and/or melanitation, including tanning of the mosquito egg chorion and encapsulation of parasites. We have cloned Ddc from the mosquito, Aedes aegypti, and studied its expression in response to blood‐feeding, which initiates events necessary for egg maturation in mosquitoes. The Ae. aegypti Ddc cDNA was isolated via heterologous screening using a clone from Drosophila melanogaster. A resulting 1.87 kilobase (kb) clone was sequenced to reveal an open reading frame of 1464 bp, as well as 5′‐ and 3′‐untranslated segments. The inferred amino acid sequence of this clone shares 81% identity with the published Drosophila Ddc cDNA, including complete identity with twenty‐four contiguous amino acids encompassing the pyridoxal‐5‐phosphate cofactor binding domain. Analysis of an F2 intercross population derived from a parental cross between two Ae. aegypti strains (Hamburg and Moyo‐In‐Dry) allowed us to map Ddc to a locus on linkage group 2. Expression studies demonstrated the presence of a 2.1 kb message, the majority of which occurs in the ovaries where Ddc‐specific mRNA is up‐regulated in response to Ingestion of a blood meal. The potential for egg‐tanning in anautogenous mosquitoes as a model for understanding specific genetic events in the regulation of catecholamine metabolism is addressed.
The insect cytochrome oxidase I gene: evolutionary patterns and conserved primers for phylogenetic studies
Authors: Lunt D. H. , Zhang D.‐X. , Szymura J. M. , Hewltt O. M.
Published: December 2007

Insect mitochondrial cytochrome oxidase I (COI) genes are used as a model to examine the within‐gene heterogeneity of evolutionary rate and Its implications for evolutionary analyses. The complete sequence (1537 bp) of the meadow grasshopper (Chorthippus parallelus) COI gene has been determined, and compared with eight other Insect COI genes at both the DNA and amino acid sequence levels. This reveals that different regions evolve at different rates, and the patterns of sequence variability seems associated with functional constraints on the protein. The COOH‐terminal was found to be significantly more variable than Internal loops (I), external loops (E), transmembrane helices (M) or the NH2 terminal. The central region of COI (M5‐M8) has lower levels of sequence variability, which Is related to several Important functional domains In this region. Highly conserved primers which amplify regions of different variabilities have been designed to cover the entire insect COI gene. These primers have been shown to amplify COI in a wide range of species, representing all the major insect groups; some even In an arachnid. Implications of the observed evolutionary pattern for phylogenetic analysis are discussed, with particular regard to the choice of regions of suitable variability for specific phylogenetic projects.
The structure, sequence and developmental pattern of expression of the white gene in the blowfly Lucilia cuprina
Authors: Garcia R. L. , Perkins H. D. , Howells A. J.
Published: December 2007

We have sequenced the complete coding region of the white gene of Lucilia cuprina. Strong sequence identity exists between this gene and its homologue from Drosophila melanogaster at both nucleotide and derived amino acid levels (68% and 78% respectively). The exon/intron structure of the two genes is also largely conserved, although the Lucilia gene contains one extra Won. Expression of the gene peaks during mid‐pupal stage, with secondary peaks in late larval and early adult stages. Comparisons between this and other white genes will contribute to a better understanding of ATP‐binding transmembrane transport proteins. The white gene should also serve as a useful marker gene in the development of a gene transformation system for the sheep blowfly.
Intravenous filters, panacea or placebo?
Authors: JOHNS TIMOTHY
Published: December 2007

Proponents of intravenous filters claim that they remove bacterial contaminants, particulate matter, air emboli and reduce the incidence of phlebitis.

From unstructured observation by the author at a large general hospital not using filters it was concluded that the incidence of complications was no greater than at a hospital having a policy for using these filters. Despite the introduction of a filter that claims to retain endotoxin for up to 96 h, filters are still misused, over used or unused in different departments of the same hospital.

This paper examines the literature that supports and criticizes the advantages and disadvantages of using such filters. The research is reviewed to ascertain whether the widespread use of filters is justified and whether they effectively reduce or prevent the complications of intravenous therapy. The paper reviews the causes and incidence of complications of intravenous therapy and alternative methods used for reducing these complications. The evidence shows conflicting results and argues that complications are inevitable despite the use of filters or careful medical action.

The manufacturer's claims are supported by a plethora of literature but discrepancies are evident and the author remains unconvinced of their widespread use in today's fragile economic climate when the cost of treating the adverse effects of intravenous therapy is considered.
Preoperative hair removal: a case report with implications for nursing
Authors: SMALL SANDRA P.
Published: December 2007

Preoperative hair removal has been a practice since the beginning of this century. Research in the 1970s and 1980s provide support for the contention that the procedure is unnecessary for wound asepsis and may increase the rate of surgical site infections (Seropian & Reynolds, 1971; Hamilton et al., 1977; Cruse & Foord, 1980; Court‐Brown, 1981; Alexander et al., 1983; Winfield, 1986; Fairclough et al., 1987). However, some hospitals have continued routine preoperative hair removal long after dissemination of recommendations against it. This begs the question, ‘Why is it that so often research findings are not applied in practice’.

In Stroud v. General Hospital Corp. and Pollett (1993), a man died of sepsis resulting from cuts he gave himself after he was asked by a nurse, in complete violation of the hospital's preoperative skin preparation protocol, to clip hair from his abdomen. The court held the hospital liable for the nurse's negligent breach of its protocol. The case clearly supports findings in the literature that preoperative hair removal is potentially dangerous. It reinforces the importance of strict adherence to hospital protocols which have been put in place to protect patients' safety.
Self‐care: the application of a ward philosophy
Authors: FURLONG SARAH
Published: December 2007

The purposes of this study were twofold. The first was to determine the rationale behind the adoption of a self‐care approach to nursing. The second, to determine how a self‐care philosophy is applied in practice.

The study was carried out from a phenomenological perspective, as it facilitated an understanding of nursing practice from the practitioners' perspective.

The adoption of a self‐care philosophy and approach to caring, appears to have evolved through patients need. This finding has implications for all practitioners.
Can elderly residents with memory problems be prepared for relocation?
Authors: DICKINSON DAVID
Published: December 2007

Relocation of elderly clients between residential establishments can be unsettling, although good preparation can help reduce negative effects and contribute to successful transfer. However, it is less clear whether preparation is feasible for residents with cognitive deficits and clarification of this issue was the objective of the study.

Results indicated that with the exception of those with severe cognitive deterioration, residents generally retained awareness of impending relocation and reported feelings appropriate to the situation.

Implications for the types of preparation are discussed.
Patient‐controlled analgesia: a review of the literature
Authors: WILLIAMS CAROLINE
Published: December 2007

Patient‐controlled analgesia is rapidly becoming accepted as an important method of providing pain relief.

A description of the technique is provided and its subsequent development traced.

Following this, the review of the literature organizes the information into the following categories:

clinical application,

efficacy,

economic factors,

patient and staff acceptance,

patient education,

potential complication.

Areas for future investigation are suggested.
Feminist approaches to change and nursing development
Authors: BILEY ANNA , WHALE ZOE
Published: December 2007

In Britain, nursing development units (NDUs) have provided a focus for change and innovation in nursing since the early 1980s. This paper explores the approaches to change in these areas of practice.

A review of both the management of change and feminist literature has been conducted. By identifying the similarities between the management of change in NDUs and feminism, it is suggested that feminist philosophies as demonstrated in NDUs may provide the key to successful and sustained, patient‐focused changes in practice.
Credit where credit's due – work‐based learning in professional practice
Authors: HARGREAVES JANET
Published: December 2007

Professional education is constantly changing.

It is important to value practice as an integral part of professional education.

Work‐based learning offers a vehicle for the linking of theoretical and clinical academic development.

The tripartite agreement between employer, student and university can be beneficial to all parties.
What do elderly people do in hospital?
Authors: BIRCHALL RUTH , WATERS KAREN R.
Published: December 2007

Current health‐care reforms have sharpened the focus on efficiency of bed usage; one useful method of exploring this concept is to determine how patients spend their time in hospital.

This small study explored how 23 elderly patients spent their time on two elderly care wards.

A time‐sampling, patient‐focused, structured observation method was employed to observe the patients. The most commonly observed activity was eating and drinking.

The findings, in keeping with previous work, suggest that therapeutic activities occupy a minimal proportion of the patient's day.

Reasons for inactivity are explored and recommendations made for further research.
Creating consensus about nursing outcomes. I. An exploration of focus group methodology
Authors: MILLAR BRIAN , MAGGS CHRISTOPHER , WARNER VICKI , WHALE ZOE
Published: December 2007

The aim of this study is to explore a method for achieving consensus about nursing outcomes between patients, nurses and health professionals.

Focus group work as a research tool is described and reviewed.

Problems of recruiting and facilitating such groups are highlighted.

The relationship between focus groups and consensus is discussed.

It is concluded that focus group work is not without problems, yet means of incorporating patient views into health services need to be developed.
Using vignettes to collect data for nursing research studies: how valid are the findings?
Authors: GOULD DINAH
Published: December 2007

Vignettes are simulations of real events which can be used in research studies to elicit subjects' knowledge, attitudes or opinions according to how they state they would behave in the hypothetical situation depicted.

Advantages associated with the use of vignettes as research tools include: the ability to collect information simultaneously from large numbers of subjects, to manipulate a number of variables at once in a manner that would not be possible in observation studies, absence of observer effect and avoidance of the ethical dilemmas commonly encountered during observation.

Difficulties include problems establishing reliability and validity, especially external validity.

This paper considers the advantages and disadvantages associated with the use of vignettes as data collection tools, concluding with a check‐list to help critique vignettes studies.
Self‐medication in acute surgical wards
Authors: JONES L. , ARTHURS G. J. , STURMANB E. , BELLIS L.
Published: December 2007

Self‐medication of oral drugs is not current practice on surgical wards.

We have introduced a system for suitable patients in which they give to themselves all their oral medication while in hospital. This was introduced in stages to gain the confidence of staff.

Many patients wish to self‐medicate; this system allows better use of the drugs that they bring into hospital from home; more appropriate timing when in hospital and speeds up discharge procedures, as the patient is already familiar with, and has a supply of, their drugs to take home.
The decision to prolong life: ethical perspectives of a clinical dilemma
Authors: TRNOBRANSKI PHILIPPA H.
Published: December 2007

As a result of rapid developments in medical technology, health‐care workers are increasingly faced with decisions regarding the prolongation of life and the withdrawal of treatment. Such decisions are often extremely complex and present a moral dilemma: they are further complicated by prevailing politico‐economic, social and cultural influences.

This article contrasts deontological and utilitarian philosophical perspectives, and discusses ethical principles which impinge on the decision making process.

A knowledge and understanding of these philosophies and principles are essential to assist clinical practitioners in the examination of moral issues surrounding life and death.
Audit or research – what is the difference?
Authors: CLOSS S. J. , CHEATER F. M.
Published: December 2007

Audit and research are activities which have some characteristics in common and others which are rather different.

This paper presents working definitions of each process and then examines their attributes and interrelationships in some detail.

Areas covered include their purposes, what types of process they are, their theoretical bases, the methods used in each, sampling, the use of findings, confidentiality and the time frame of each.

If nurses are to use or undertake research and/or audit appropriately in their practice, it is important that the similarities and differences between the two are clear.
Paediatric nursing and children's autonomy
Authors: LOWES LESLEY
Published: December 2007

The topic of children's rights is a wide‐ranging and complex subject, and in recognition of this fact this paper specifically addresses the concept of the right of children to make decisions about their own health‐care.

This paper explores the many factors which may influence a child's right to autonomy, including family relationships and the broader external influences exerted by health‐care workers.

The discussion highlights the dilemmas which may be faced by nurses when their values and beliefs, or hierarchical position within the health‐care structure, inhibit their ability to promote children's autonomy.
An evaluation of the King's Fund Centre Nursing Development Unit Network 1989–91
Authors: PEARSON ALAN
Published: December 2007

This article reports on a study carried out in 1991 of the King's Fund team and the Nursing Development Unit network.

The study is essentially descriptive and largely qualitative in nature and cannot therefore be the basis of generalization.

Overall, it illuminates the emergence of a large number of embryonic nursing development units across the UK.

The findings suggest that the NDU network established by the King's Fund has played an important role in the initiation of a number of these units and in providing them with ongoing support.
Transcending chronic liver disease: a qualitative study
Authors: WAINWRIGHT STEVEN P.
Published: December 2007

This study explores and describes experiences of chronic liver disease from the patient's perspective. No qualitative research studies appear to have examined the experiences of these patients. In–depth focused interviews and grounded theory data collection and data analysis methods were used. A two‐stage theoretical framework (becoming ill, and not living) of the experience of transcending chronic liver disease is presented.

Sociological and psychological literature on common sense models of health and illness are briefly reviewed. Several suggestions for further research are made. The way in which this qualitative research study is leading to a quantitative and qualitative appraisal of the psychological adjustment in end‐stage chronic liver disease patients is outlined.
Chronic illness: the importance of support for families caring for a child with cystic fibrosis
Authors: COYNE IMELDA T.
Published: December 2007

The effect of chronic life‐threatening illness on the family is one of the major problems confronting the health‐care system today. Increasingly, parents have the major responsibility for the daily management of their child's condition.

There is evidence that many parents lack the pofessional help and support which could ameliorate some of their problems. It is important that nurses have an understanding of how families cope with the burden of caring for a chronically ill child.

Health professionals need clear guidelines on how to support these families in their role as primary care‐givers.

This paper examines how families of children with cystic fibrosis adapt to the illness in order to provide indicators for nursing practice and to enhance the care and support provided for these families.

Effective coping strategies include: assigning meaning to the illness, sharing the burden, denial of diagnosis and incorporating therapy in a schedule.
Evaluation of stress prevention and management workshops in the community
Authors: HOSTICK TONY , NEWELL ROB , WARD TIM
Published: December 2007

Little emphasis has been placed by clinicians on the need for routine evaluation of outcomes of community mental health nursing interventions. Although numerous descriptive studies exist, there is little systematic evaluation of the work of community mental health nurses, and this problem is particularly acute in the field of preventative work.

This paper presents the results of a small initiative to incorporate outcome evaluation into the clinical work of a community mental health team.

Ninety‐nine participants in a series of stress management workshops completed stress questionnaires before a series of 2‐day workshops and were followed up at between 3 and 6 months afterwards.

At follow‐up, participants reported greater gains in terms of stress management than did no‐treatment controls.

The study offers tentative evidence for the effectiveness of community mental health nurses in offering effective preventative interventions and also indicates that such interventions are amenable to outcome evaluation within the context of routine clinical practice.
Changes in reported dietary habit and exercise levels after an uncomplicated first myocardial infarction in middle‐aged men
Authors: NEWENS ANDREW J. , MCCOLL ELAINE , BOND SENGA
Published: December 2007

Education of patients and their partners about appropriate lifestyle changes following myocardial infarction (MI) is a key element in rehabilitation; developing relevant educational strategies requires a knowledge of patient beliefs and attitudes. This paper reports findings from a survey of diet and exercise in a group of 153 middle‐aged men who had suffered a first uncomplicated MI.

Just over half of those questioned expressed a desire to change their diet post‐MI; those who perceived their pre‐morbid diet to be ‘less healthy’ were more likely to want to change. Significant changes in food consumption (towards a more healthy diet) were observed at 3 months post‐MI. Patients were less likely to change their behaviour with respect to exercise, and few attained recommended levels of physical activity either pre‐ or post‐MI.

Patients held a number of misconceptions regarding the role of diet and exercise in predisposing to coronary heart disease, and the need for change in behaviour. Beliefs and behaviour change were only weakly associated with receipt of information and advice. The findings have important messages for the more appropriate targeting of information‐provision during the period of rehabilitation.
Nurses caring for families – issues in a multiracial society
Authors: CHEVANNES MEL
Published: December 2007

Social, racial and ethnic factors are examined as key issues which affect nurses caring for families.

A co‐ordinated approach to caring for all families means that diverse clinical or therapeutic nursing may result.

Quality caring for all families requires improved education, at pre‐ and post‐registration levels, about the relationship between race and ethnicity and families' health, and the treatment regimens undertaken by families.

Effective caring for families from different social, racial and ethnic groups is still at a rudimentary level.

Orem's (1989) self‐care nursing model is explored to show how ethnic differences and similarities among families are incorporated into caring.
Underwater seal chest drains: the patient's experience
Authors: OWEN SUZANNE , GOULD DINAH
Published: December 2007

Chest drains are routinely inserted during thoracic surgery and to conservatively manage spontaneous pneumothorax.

An extensive search of the literature revealed only a small number of highly prescriptive articles to advise the nurse on the specific care needs of this patient group.

An exploratory study undertaken with 18 patients drew attention to the persistent discomfort and pain experienced by patients throughout the entire time that the chest drain remained in situ.

Most of the patients also experienced short‐lasting but intense pain when the chest drain was removed.

Patients appeared ill‐prepared for their experiences despite opportunities to obtain verbal and written information from staff.