bluuebunny/crossref_metadata_2025 huggingface dataset:
Temporal variation of the population structure and genetic diversity of Farfantepenaeus notialis assessed by allozyme loci
Authors: BARCIA AYMÉE ROBAINAS , LÓPEZ GEORGINA ESPINOSA , HERNÁNDEZ DAMIR , GARCÍA‐MACHADO ERIK
Published: August 2005

Population genetic studies carried out on penaeid shrimps have disclosed different patterns of population subdivision, revealing new aspects of shrimp biology as well as the effects of historical contingency molding those patterns. However, the stability of observed allele frequencies over time still remains untested. The objective of this article is to show the analysis of the temporal variation of allozymes in a shrimp species inhabiting Cuba which proves that the genetic structure of this species could significantly change in time. The study involves four populations of Farfantepenaeus notialis sampled in a period of 8 years. The significant statistics obtained from partitions observed in 1995 were not detected in 2003 (as suggested by amova and FST), whereas temporal genetic differentiation and heterozygosity became highly significant. The results strongly suggest that the effect of migrations could be the cause for the loss of F. notialis genetic structure in 2003. It is therefore imperative to call attention on the vulnerability of these populations when facing unstable environmental and habitat conditions.
Sequence polymorphism of candidate behavioural genes inDrosophila melanogasterflies from ‘Evolution canyon’
Authors: ZAMORZAEVA I. , RASHKOVETSKY E. , NEVO E. , KOROL A.
Published: August 2005

This study focuses on the molecular features of three candidate behavioural genes inDrosophila melanogasterfrom the opposite slopes of Nahal Oren Canyon, Mount Carmel, Israel. These slopes display dramatic physical and biotic contrasts. Spatial variation of microclimatic conditions leads to adaptive differentiation and partial sexual isolation of populations, as suggested by our previous studies. The chosen candidate genes presumably contributing to genetic variation in sexual behaviour ofDrosophilain the Canyon weredesaturase,period, andno‐on‐transient A. These genes are known to include polymorphic repeated sequences, insertions/deletions, or nucleotide substitutions. The idea was that their polymorphism might be one of the determinants of behavioural peculiarities of flies derived from the opposite slopes. Indeed, interslope differences in the sequence encoding the (Thr‐Gly)nrepeat (exon 5) of theperiodgene were established, suggesting evolutionary functional importance. In particular, we unraveled variation in the length and composition of this region in different NFS (north‐facing slope) and SFS (south‐facing slope) lines. The ‘European’ allele (n = 20) was a 2.6‐fold more abundant on the NFS compared to the SFS. This predominance probably gives some advantages for flies inhabiting wet and less warm conditions of the NFS. We suggest that repeat length/composition may influence the functional features of flies, i.e. habitat choice, nonrandom mating, and temperature adaptation. A series of female single‐mate‐choice tests show that females derived from NFS distinguish between males with specificperalleles (n = 17 vs.n = 20), as well as between males originated from the opposing slopes. Females from SFS were less discriminating and did not manifest significant deviation from random mating.
Estimating pollen flow using SSR markers and paternity exclusion: accounting for mistyping
Authors: SLAVOV G. T. , HOWE G. T. , GYAOUROVA A. V. , BIRKES D. S. , ADAMS W. T.
Published: August 2005

Highly informative genetic markers, such as simple sequence repeats (SSRs), can be used to directly measure pollen flow by parentage analysis. However, mistyping (i.e. false inference of genotypes caused by the occurrence of null alleles, mutations, and detection errors) can lead to substantial biases in the estimates obtained. Using computer simulations, we evaluated a direct method for estimating pollen immigration using SSR markers and a paternity exclusion approach. This method accounts for mistyping and does not rely on assumptions about the distribution of male reproductive success. If ignored, even minor rates of mistyping (1.5%) resulted in overestimating pollen immigration by up to 150%. When we required at least two mismatching loci before excluding candidate fathers from paternity, the resulting pollen immigration estimates had small biases for rates of mistyping up to 4.5%. Requiring at least three mismatches for exclusion was needed to minimize the upward biases of pollen immigration caused by rates of mistyping up to 10.5%. The minimum number of highly variable SSR loci needed to minimize cryptic gene flow and obtain reliable estimates of pollen immigration varied from five to seven for a sampling scheme applicable to most conifers (i.e. when paternal haplotypes can be unambiguously determined). Between five and nine highly variable SSR loci were needed for a more general sampling scheme that is applicable to all diploid seed plants. With moderately variable SSR markers, consistently accurate estimates of pollen immigration could be obtained only for rates of mistyping up to 4.5%. We developed the pollen flow (pfl) computer program which can be used to obtain unbiased and precise estimates of pollen immigration under a wide range of conditions, including population sizes as large as 600 parents and mistyping rates as high as 10.5%.
Hares on ice: phylogeography and historical demographics of Lepus arcticus, L. othus, and L. timidus (Mammalia: Lagomorpha)
Authors: WALTARI ERIC , COOK JOSEPH A.
Published: August 2005

Phylogeographical investigations of arctic organisms provide spatial and temporal frameworks for interpreting the role of climate change on biotic diversity in high‐latitude ecosystems. Phylogenetic analyses were conducted on 473 base pairs of the mitochondrial control region in 192 arctic hares (Lepus arcticus, Lepus othus, Lepus timidus) and two individual Lepus townsendii. The three arctic hare species are closely related. All L. othus individuals form one well‐supported clade, L. arcticus individuals form two well‐supported clades, and L. timidus individuals are scattered throughout the phylogeny. Arctic hare distribution was altered dramatically following post‐Pleistocene recession of continental ice sheets. We tested for genetic signatures of population expansion for hare populations now found in deglaciated areas. Historical demographic estimates for 12 arctic hare populations from throughout their range indicate that L. arcticus and L. othus persisted in two separate North American arctic refugia (Beringia and High Canadian Arctic) during glacial advances of the Pleistocene, while the high genetic diversity in L. timidus likely reflects multiple Eurasian refugia.
Comparative landscape genetics and the adaptive radiation of Darwin's finches: the role of peripheral isolation
Authors: PETREN K. , GRANT P. R. , GRANT B. R. , KELLER L. F.
Published: August 2005

We use genetic divergence at 16 microsatellite loci to investigate how geographical features of the Galápagos landscape structure island populations of Darwin's finches. We compare the three most genetically divergent groups of Darwin's finches comprising morphologically and ecologically similar allopatric populations: the cactus finches (Geospiza scandensandGeospiza conirostris), the sharp‐beaked ground finches (Geospiza difficilis) and the warbler finches (Certhidea olivaceaandCerthidea fusca). Evidence of reduced genetic diversity due to drift was limited to warbler finches on small, peripheral islands. Evidence of low levels of recent interisland migration was widespread throughout all three groups. The hypothesis of distance‐limited dispersal received the strongest support in cactus and sharp‐beaked ground finches as evidenced by patterns of isolation by distance, while warbler finches showed a weaker relationship. Support for the hypothesis that gene flow constrains morphological divergence was only found in one of eight comparisons within these groups. Among warbler finches, genetic divergence was relatively high while phenotypic divergence was low, implicating stabilizing selection rather than constraint due to gene flow. We conclude that the adaptive radiation of Darwin's finches has occurred in the presence of ongoing but low levels of gene flow caused by distance‐dependent interisland dispersal. Gene flow does not constrain phenotypic divergence, but may augment genetic variation and facilitate evolution due to natural selection. Both microsatellites and mtDNA agree in that subsets of peripheral populations of two older groups are genetically more similar to other species that underwent dramatic morphological change. The apparent decoupling of morphological and molecular evolution may be accounted for by a modification of Lack's two‐stage model of speciation: relative ecological stasis in allopatry followed by secondary contact, ecological interactions and asymmetric phenotypic divergence.
Control of body size ofLasius nigerant sexuals — worker interests, genes and environment
Authors: FJERDINGSTAD ELSE J.
Published: August 2005

In most animals, the survival and reproductive success of males and females is linked to their size. The ability of individuals to control environmental influences on size will therefore have consequences for their fitness. In eusocial insects, individual males and reproductive females do not have to forage for themselves or control their local environment. Instead, they are reared by nonreproductive siblings (workers) inside colonies. Workers should benefit from controlling the size of sexuals because these sexuals are usually the only means for workers to transmit their genes to future generations. Nevertheless, considerable intraspecific variation exists around mean sexual size in social hymenopterans, even in species with monomorphic sexuals. This variation could result from genetic influences on sexual size, for instance sexuals may be selected to not agree to worker interests, or be due to strong, unpredictable environmental conditions constraining the efforts of workers to control sexual size. In a study that is the first of its kind I investigated genetic and environmental components of sexual body size variation in the antLasius niger, examining sexuals from wild colonies with one or several fathers (paternity levels established through microsatellite DNA offspring analysis). Evidence was found for a genetic component of size (broad‐sense heritability of up to 42%) but strong common‐colony effects (among‐colony variation in food availability or in worker capacities to restrain sexual selfishness) also increased the size differences among colonies. Workers thus seem to only have partial‐control over sexual size, but may be doing the best of a bad job.
Growth, productivity, and competitiveness of introgressed weedy Brassica rapa hybrids selected for the presence of Bt cry1Ac and gfp transgenes
Authors: HALFHILL MATTHEW D. , SUTHERLAND JAMIE P. , MOON HONG SEOK , POPPY GUY M. , WARWICK SUZANNE I. , WEISSINGER ARTHUR K. , RUFTY THOMAS W. , RAYMER PAUL L. , STEWART C. NEAL
Published: August 2005

Concerns exist that transgenic crop × weed hybrid populations will be more vigorous and competitive with crops compared with the parental weed species. Hydroponic, glasshouse, and field experiments were performed to evaluate the effects of introgression of Bacillus thuringiensis (Bt) cry1Ac and green fluorescent protein (GFP) transgenes on hybrid productivity and competitiveness in four experimental Brassica rapa × transgenic Brassica napus hybrid generations (F1, BC1F1, BC2F1 and BC2F2). The average vegetative growth and nitrogen (N) use efficiency of transgenic hybrid generations grown under high N hydroponic conditions were lower than that of the weed parent (Brassica rapa, AA, 2n = 20), but similar to the transgenic crop parent, oilseed rape (Brassica napus, AACC, 2n = 38). No generational differences were detected under low N conditions. In two noncompetitive glasshouse experiments, both transgenic and nontransgenic BC2F2 hybrids had on average less vegetative growth and seed production than B. rapa. In two high intraspecific competition field experiments with varied herbivore pressure, BC2F2 hybrids produced less vegetative dry weight than B. rapa. The competitive ability of transgenic and nontransgenic BC2F2 hybrids against a neighbouring crop species were quantified in competition experiments that assayed wheat (Triticum aestivum) yield reductions under agronomic field conditions. The hybrids were the least competitive with wheat compared with parental Brassica competitors, although differences between transgenic and nontransgenic hybrids varied with location. Hybridization, with or without transgene introgression, resulted in less productive and competitive populations.
Interfamilial characterization of a region of the ZFX and ZFY genes facilitates sex determination in cetaceans and other mammals
Authors: MORIN PHILLIP A. , NESTLER AVIVA , RUBIO‐CISNEROS NADIA T. , ROBERTSON KELLY M. , MESNICK SARAH L.
Published: August 2005

Sequence polymorphism of homologues ZFX and ZFY, in a 604‐base pair exon region, was examined in 10 known males and 10 known females across seven cetacean families and used to design a simple, highly sensitive and widely applicable fluorescent 5′ exonuclease assay for gender determination in cetaceans. Multiplex amplification, cloning, and sequencing of these previously uncharacterized regions revealed (i) eight fixed differences between ZFX and ZFY, (ii) 29 variable sites between ZFX and ZFY and (iii) very low interspecific nucleotide diversity for both ZFX and ZFY across all families examined. We developed a 5′ exonuclease assay that produces a small (105 bp) polymerase chain reaction (PCR) product from both the X and the Y chromosome orthologs, and used double‐labelled fluorescent probes to distinguish between the two genes in a real‐time PCR assay that is highly reproducible and sensitive. We demonstrated sex specificity for 33 cetacean species in nine families. Given the availability of conserved primers and sequence information for many mammalian species, this approach to designing sexing assays for a wide range of species is both practical and efficient.
Gene expression patterns accompanying a dietary shift in Drosophila melanogaster
Authors: CARSTEN L. D. , WATTS T. , MARKOW T. A.
Published: August 2005

The ability of many organisms to switch to new hosts can be critical to their survival in the wild. However, the genetic mechanisms underlying such shifts are poorly understood. In this study, we used complementary DNA (cDNA) microarrays to ask if changes in gene expression are observed in response to a dietary shift in Drosophila melanogaster, a dietary generalist. We found significant and repeatable differential expression in a number of genes related to metabolic function and stress, suggesting that a functional genomics approach will be useful in seeking loci involved in the ability of flies to utilize different resources.
Migratory charr schools exhibit population and kin associations beyond juvenile stages
Authors: FRASER DYLAN J. , DUCHESNE PIERRE , BERNATCHEZ LOUIS
Published: August 2005

Few studies have critically investigated the genetic composition of wild fish schools. Yet, such investigations may have profound implications for the understanding of social organization and population differentiation in both fundamental and applied research. Using 20 microsatellite loci, we investigated the composition of 53 schools (totaln = 211) of adult and subadult migratory brook charr (Salvelinus fontinalis) sampled from the known feeding areas of two populations inhabiting Mistassini Lake (Québec, Canada). We specifically tested whether (i) school members originated from the same population, (ii) individuals from the same population within schools were kin (half‐ or full‐siblings), and (iii) kin schooling relationships differed between sexes. Randomization tests revealed a tendency for most schools to be population specific, although some schools were population mixtures. Significantly more kin were found within schools than expected at random for both populations (≈ 21–34% of the total number of school members). This result, combined with the observed size range of individuals, indicated that stable associations between kin may occur beyond juvenile stages for up to 4 years. Nevertheless, a high proportion of school members were non‐kin (≈ 66–79%). No differences were detected between sexes in the propensity to school with kin. We discuss the hypothesis that the stable kin groups, rather than arising from kin selection, may instead be a by‐product of familiarity based on individual selection for the maintenance of local adaptations related to migration (natal and feeding area philopatry). Our results are noteworthy because they suggest that there is some degree of permanence in the composition of wild fish schools. Additionally, they support the hypothesis that schools can be hierarchically structured (from population members down to family groups) and are thus nonrandom genetic entities.
Marine landscapes and population genetic structure of herring (Clupea harengus L.) in the Baltic Sea
Authors: JØRGENSEN HANNE B. H. , HANSEN MICHAEL M. , BEKKEVOLD DORTE , RUZZANTE DANIEL E. , LOESCHCKE VOLKER
Published: August 2005

Numerically small but statistically significant genetic differentiation has been found in many marine fish species despite very large census population sizes and absence of obvious barriers to migrating individuals. Analyses of morphological traits have previously identified local spawning groups of herring (Clupea harengus L.) in the environmentally heterogeneous Baltic Sea, whereas allozyme markers have not revealed differentiation. We analysed variation at nine microsatellite loci in 24 samples of spring‐spawning herring collected at 11 spawning locations throughout the Baltic Sea. Significant temporal differentiation was observed at two locations, which we ascribe to sympatrically spawning but genetically divergent ‘spawning waves’. Significant differentiation was also present on a geographical scale, though pairwise FST values were generally low, not exceeding 0.027. Partial Mantel tests showed no isolation by geographical distance, but significant associations were observed between genetic differentiation and environmental parameters (salinity and surface temperature) (0.001 < P≤ 0.099), though these outcomes were driven mainly by populations in the southwestern Baltic Sea, which also exhibits the steepest environmental gradients. Application of a novel method for detecting barriers to gene flow by combining geographical coordinates and genetic differentiation allowed us to identify two zones of lowered gene flow. These zones were concordant with the separation of the Baltic Sea into major basins, with environmental gradients and with differences in migration behaviour. We suggest that similar use of landscape genetics approaches may increase the understanding of the biological significance of genetic differentiation in other marine fishes.
Phylogeography of pollinator‐specific sexually deceptiveChiloglottistaxa (Orchidaceae): evidence for sympatric divergence?
Authors: MANT J. , BOWER C. C. , WESTON P. H. , PEAKALL R.
Published: August 2005

Divergence in sexually deceptive orchids is thought to occur through shifts in the attraction of specific pollinators, a process that is mediated by changes in the floral odours that lure sexually excited male insects. We investigated the origin of reproductive isolation in a sexually deceptive species complex ofChiloglottisR.Br. (Orchidaceae: Diurideae). Two geographically separated montane regions in eastern Australia were sampled, each containing sympatric pairs of orchid taxa presently found under the name,Chiloglottis pluricallata. Behavioural tests confirmed at least three distinct orchid taxa that specifically attract different pollinators. An artificial crossing experiment among two taxa from one region demonstrated their interfertility, and confirmed isolation to be a function of pollinator attraction. A phylogeographic analysis using amplified fragment length polymorphisms (AFLPs) indicated that samples from each geographical region are most closely related, a pattern consistent within situor sympatric divergence. However, an extensive population genetic study on two taxa from one region failed to entirely reject the possibility of intertaxon gene flow. Although clear genetic differentiation of the taxa is evident in two out of three sites where both grow in direct sympatry, overall, the two taxa are not strongly distinguished by AFLP markers. The reconstruction of a simple bifurcating pattern of divergence may be confounded by a combination of contemporary population‐level processes operating within each taxon, the retention of ancestral polymorphism or intertaxon gene flow.
Genetic variation and population structure in remnant populations of black rhinoceros, Diceros bicornis, in Africa
Authors: HARLEY ERIC H. , BAUMGARTEN INGRID , CUNNINGHAM JESSICA , O'RYAN COLLEEN
Published: August 2005

Black rhinoceros (Diceros bicornis) are one of the most endangered mammal species in Africa, with a population decline of more than 96% by the end of the last century. Habitat destruction and encroachment has resulted in fragmentation of the remaining populations. To assist in conservation management, baseline information is provided here on relative genetic diversity and population differentiation among the four remaining recognized subspecies. Using microsatellite data from nine loci and 121 black rhinoceros individuals, and comparing the results with those of other African species affected in similar ways, Diceros bicornis michaeli retained the most genetic diversity (heterozygosity 0.675) compared with Diceros bicornis minor (0.459) and Diceros bicornis bicornis (0.505), suggesting that the duration of the known bottlenecks in these populations has only had a limited impact on diversity. Comparable and moderate degrees of population differentiation were found between D. b. minor, D. b. bicornis and D. b. michaeli. Results from the single sample available of the most endangered subspecies, Diceros bicornis longipes, showed the least diversity of all individuals examined. This information should assist conservation management decisions, especially those affecting population viability assessments and selection of individuals for translocations, and will also facilitate subspecies identification for ex situ individuals of uncertain origin.
Age‐specific mating strategies and reproductive senescence
Authors: RICHARD M. , LECOMTE J. , DE FRAIPONT M. , CLOBERT J.
Published: August 2005

While males gain obvious direct advantages from multiple mating, the reproductive capacity of females is more constrained. The reason why polyandry evolved in females is therefore open to many conjectures. One hypothesis postulates that females gain indirect benefits by increasing the probability of siring young from high quality males. To explore this hypothesis, we used the natural variation of the reproductive value that males and females undergo through age. The age‐related variation of phenotypic performance might then induce variations in mating strategies in males and females. Using the common lizard (Lacerta vivipara) as our model system, we showed that reproductive immaturity and senescence created variability in both male and female reproductive success (including survival of offspring). Consistent with theory, males at their best‐performing phenotype adopted a polygynous strategy. These males were of an intermediate age and they produced offspring of higher viability than younger and older males. In contrast, females at their best performing phenotype, also of an intermediate age, were less polyandrous than other less‐ performing females. Middle‐aged females tended to mate with males of an intermediate age and produced litters with higher viability independently from their reproductive strategy. Males of an intermediate age enhanced their fitness by additional matings with young or old females. Young and old females increased their fitness by being more polyandrous. Polyandry therefore appears as means to seek for good males. A positive correlation between males and their partners’ fitness disagree with the idea that polyandry is the result of a sexual conflict in this species.
Mitochondrial DNA phylogeography of the Mesoamerican spiny‐tailed lizards (Ctenosaura quinquecarinatacomplex): historical biogeography, species status and conservation
Authors: HASBÚN CARLOS ROBERTO , GÓMEZ AFRICA , KÖHLER GUNTHER , LUNT DAVID H.
Published: August 2005

Through the examination of past and present distributions of plants and animals, historical biogeographers have provided many insights on the dynamics of the massive organismal exchange between North and South America. However, relatively few phylogeographic studies have been attempted in the land bridge of Mesoamerica despite its importance to better understand the evolutionary forces influencing this biodiversity ‘hotspot’. Here we use mitochondrial DNA sequence data from fresh samples and formalin‐fixed museum specimens to investigate the genetic and biogeographic diversity of the threatened Mesoamerican spiny‐tailed lizards of theCtenosaura quinquecarinatacomplex. Species boundaries and their phylogeographic patterns are examined to better understand their disjunct distribution. Three monophyletic, allopatric lineages are established using mtDNA phylogenetic and nested clade analyses in (i) northern: México, (ii) central: Guatemala, El Salvador and Honduras, and (iii) southern: Nicaragua and Costa Rica. The average sequence divergence observed between lineages varied between 2.0% and 3.7% indicating that they do not represent a very recent split and the patterns of divergence support the recently established nomenclature ofC. quinquecarinata,Ctenosaura flavidorsalisandCtenosaura oaxacana. Considering the geological history of Mesoamerica and the observed phylogeographic patterns of these lizards, major evolutionary episodes of their radiation in Mesoamerica are postulated and are indicative of the regions’ geological complexity. The implications of these findings for the historical biogeography, taxonomy and conservation of these lizards are discussed.
Multilocus estimation of pairwise relatedness with dominant markers
Authors: RITLAND KERMIT
Published: August 2005

Estimators for pairwise relatedness designed for dominant markers are derived, based on a genetic model that accounts for the full structure of pairwise relatedness between two individuals at a diploid locus with dominance. They jointly estimate ‘relatedness’ and ‘fraternity’, in which case the estimators are inherently multilocus, as at least two loci of differing gene frequency are required. Extensions to cases of zero fraternity and isolation by distance (inbreeding) are also examined. Properties of estimators are examined by simulation and compared to the estimator of Hardy. The most statistical power for pairwise relatedness occurs when roughly half of individuals are the recessive phenotype. Estimation procedures are implemented in the computer program mark.
Use of doramectin for treatment of sarcoptic mange in five Angora rabbits
Authors: VOYVODA HUSEYIN , ULUTAS BULENT , EREN HASAN , KARAGENC TULIN , BAYRAMLI GOKSEL
Published: August 2005

Abstract  The efficacy of administering doramectin after moxidectin treatment, which has previously proved only partially effective, was evaluated in five Angora rabbits naturally infested with Sarcoptes scabiei mange. Evaluations included physical examination for clinical signs of sarcoptic mange and collection of skin scrapings for determination of mites. The rabbits first received two subcutaneous injections, 10 days apart, of moxidectin 1% injectable solution at a dosage of 0.2 mg kg−1 of bodyweight. Although moxidectin treatment resulted in clinical improvement within 10 days post initial injection, on days 10 and 35 post initial treatment live mites were present in skin scrapings. Administration of doramectin 1% injectable solution using the same route and dosage and at similar intervals to moxidectin led to complete disappearance of signs of scabies and parasitological cure in all rabbits.
Bilateral ear canal neoplasia in three dogs
Authors: ZUR GILA
Published: August 2005

Abstract Bilateral ear canal infections are common in dogs. Ear canal neoplasia is usually associated with unilateral problems, and is uncommon in dogs. To the best of the author's knowledge, bilateral aural neoplasia has not been reported in dogs, and only four case reports were found in the human literature. This report presents three dogs that had bilateral tumours in their ear canals. They were presented with bilateral otitis externa. All three dogs exhibited tissue proliferation of both ear canals that did not respond to glucocorticoids. Treatment consisted of total ear canal ablation, and tissues were submitted for histopathological evaluation. Case # 1 (a 10‐year‐old, male cocker spaniel) was diagnosed as ceruminious gland carcinoma. Cases # 2 and 3 were diagnosed as squamous cell carcinoma. Case # 1 was diagnosed 4 years earlier as having keratinization disorder, which was causing its chronic ear problems. Case # 2 (a 5‐year‐old, female French bulldog) was diagnosed 4 years earlier as having atopic dermatitis, which did not respond to hyposensitization, and only partially responded to glucocorticoids therapy. Case # 3 (a 9‐year‐old, male German shepherd) was diagnosed by the referring veterinarian as having unilateral ear canal proliferation 2 months prior to presentation. However, otoscopic examination showed bilateral proliferation that obstructed both canals. In summary, bilateral ear canal neoplasia should be considered in cases of nonresponsive, proliferative aural pathology.
Zinc‐responsive dermatosis in goats suggestive of hereditary malabsorption: two field cases
Authors: KRAMETTER‐FROETSCHER REINHILD , HAUSER SIMONE , BAUMGARTNER WALTER
Published: August 2005

Abstract Two cases of zinc deficiency in dairy goats from different flocks and not associated with a zinc‐deficient diet are described. Hard, dry, hyperkeratotic skin, hair loss and pruritus especially prominent on the back, legs, udder, face and ears were the most common clinical signs. Skin biopsy findings revealed a mixture of orthokeratotic and parakeratotic hyperkeratosis. On initial examination, serum zinc concentrations were low in both goats (461 µg L−1and 521 µg L−1, respectively). Although mild skin lesions persisted during the early stages of zinc supplementation, skin lesions completely resolved after prolonged oral zinc supplementation. Withdrawal of zinc supplementation resulted in re‐appearance of lesions in both animals. Case 2 gave birth to two kids, one of which showed mild skin lesions at 8 months of age together with a low serum zinc concentration (434 µg L−1), suggestive of hereditary zinc malabsorption. The other kid remained free of skin lesions and had a serum zinc concentration (530 µg L−1) within the normal range. On the basis of historical and clinical findings, the cases presented here more closely resemble Syndrome 1 hereditary zinc deficiency as seen in Nordic dog breeds rather than other zinc deficiency conditions seen in other species. It is suggested that zinc deficiency in these goats was due to hereditary malabsorption of dietary zinc. This is the first descriptive study of this condition in goats. Life‐long zinc supplementation may be necessary in such patients.
Treatment of canine Old World visceral leishmaniasis: a systematic review
Authors: NOLI CHIARA , AUXILIA SILVIA T.
Published: August 2005

Abstract Canine visceral leishmaniasis is a systemic disease caused byLeishmania infantum. The aim of this systematic review was to identify and evaluate the evidence of efficacy of interventions for treatment or prevention of canine visceral leishmaniasis, and to propose recommendations for or against their use. Forty‐seven articles describing clinical trials published between 1980 and 2004 fulfilled selection criteria. The evaluation of clinical trials provided good evidence for recommending the use of meglumine antimoniate at a minimum dosage of 100 mg kg−1daily for at least 3–4 weeks, combined with allopurinol in order to obtain a good clinical efficacy and a reduced relapse rate. The evaluation of the articles also provided fair evidence for recommending the use of pentamidine (4 mg kg−1twice weekly) and aminosidine (5 mg kg−1twice daily) for 3–4 weeks. There was insufficient evidence for recommending the use of allopurinol alone, amphotericin B, buparvaquone, ketoconazole, enrofloxacin, and the combinations of metronidazole with spiramicyn or metronidazole with enrofloxacin. Fair evidence against the use of aminosidine at high dosages (20–80 mg kg−1per day) was proposed due to its side effects. Evaluation of articles on repellent measures against sand fly vectors of leishmaniasis provided good evidence for recommending deltamethrin collars and fair evidence for recommending spot‐on permethrin.
Prevalence of the group 1 Dermatophagoides allergens Der p 1 and Der f 1 in homes with no dogs, healthy dogs and Dermatophagoides‐sensitized atopic dogs in Liverpool
Authors: RAFFAN ELEANOR , LAWRENCE HELEN , HENDERSON THOMAS , NELSON SARAH , ISHERWOOD DIANA , McARDLE CLAIRE , NUTTALL TIM
Published: August 2005

Abstract  Dermatophagoides farinae is a frequent allergen in canine atopic dermatitis despite its reported scarcity in the UK, and the aim of this study was to determine whether dogs were uniquely exposed to this species. Der f 1 and Der p 1 in dust collected from living room carpets, bedroom carpets and dog beds of 13 houses with no dogs, 13 with healthy dogs, and 16 with Dermatophagoides‐sensitized atopic dogs were quantified by ELISA. Der p 1 levels (µg g−1 house dust) were significantly higher than Der f 1 in living rooms (Der p 1 median = 1.9, 95% CI = 2.05–6.32, n = 42; Der f 1 median = 0.07, 95% CI = 0.01–0.06, n = 42), bedrooms (Der p 1 median = 4.35, SD = 5.52; Der f 1 median = 0.01, 95% CI = 0.001–0.1, n = 42) and dog beds (Der p 1 median = 1.04, 95% CI = 1.4–8.1, n = 29; Der f 1 median = 0.008, 95% CI = 0.01–0.04, n = 29) (P < 0.0001). Living rooms in houses without dogs had significantly greater Der p 1 levels (median = 7.0, 95% CI = 3.53–15.8, n = 13) than houses with healthy (median = 1.19, 95% CI = 0.44–3.49, n = 13) or atopic dogs (median = 0.78, 95% CI = 0.63–2.42, n = 16) (P = 0.0004). Environmental flea control in living rooms and washing dog beds was associated with significantly reduced Der p 1 levels. This confirms that D. pteronyssinus is common but D. farinae is rare in the sampling area. Apparent sensitization to D. farinae is probably due to cross‐reaction. A combination of environmental measures could reduce allergen exposure.
Clinical, histopathological and immunological characteristics of exfoliative cutaneous lupus erythematosus in 25 German short‐haired pointers
Authors: BRYDEN SHARON L. , WHITE STEPHEN D. , DUNSTON STANLEY M. , BURROWS AMANDA K. , OLIVRY THIERRY
Published: August 2005

Abstract  Clinical, histopathological and immunological features of exfoliative cutaneous lupus erythematosus, an uncommon generalized exfoliative dermatitis occurring exclusively in German short‐haired pointers, were characterized in 25 dogs. The disease affects young adult dogs and its familial incidence strongly suggests a hereditary origin. Lesions were characterized by scaling and alopecia affecting 100 (25/25) and 76% (19/25) of dogs, respectively. Follicular casts were present in 28% (7/25) of dogs. The muzzle, pinnae and dorsum were typically affected. Generalized skin lesions were described in 52% (13/25) of dogs. Systemic signs of pain and lameness affected several dogs. Anaemia and thrombocytopenia were detected in several dogs with a more severe clinical phenotype. The most common histopathological features were hyperkeratosis and a lymphocytic interface dermatitis. Direct immunostaining revealed IgG deposition in the epidermal and follicular basement membrane of 100 (19/19) and 41% (7/17) of dogs, respectively. Circulating antifollicular and antisebaceous gland IgG antibodies were demonstrated by indirect immunostaining in 57% (4/7) of dogs. This disease usually responds poorly to immunosuppressive therapy and it has a guarded prognosis. Where outcome was recorded, 85% (10/12) of dogs were euthanased due to either a failure to respond to, or complications associated with, immunomodulatory therapy. Two affected dogs are in remission and maintained on immunomodulatory dosages of prednisolone. This study demonstrates the existence of a cellular and humoral immune response directed against the epidermal basement membrane of dogs with exfoliative cutaneous lupus erythematosus. Additional studies are required to further characterize the immunological pathogenesis of this disease.
A mutated HLA‐A*0101 allele in the colorectal cell line HCA‐7
Authors: Bicknell D.C. , Bodmer W.F.
Published: August 2005

Abstract:  The colorectal cell line HCA‐7 expresses surface human leucocyte antigen‐A*0201 (HLA‐A*0201), but lacks expression of HLA‐A*0101 whilst the normal B‐cell line (EVA‐1224), derived from the same individual, expresses both surface HLA‐A1 and HLA‐A2. Amplification refractory mutation system‐polymerase chain reaction analysis, using sequence‐specific primers, suggested that HCA‐7 has a mutation in a 7 base pair (bp) cytosine repeat sequence located at the beginning of Exon 4 (bp 621–627). Cloning and sequencing revealed HCA‐7 to have eight cytosine residues in this repeat sequence. In contrast, EVA‐1224 contained only 7 cytosines. Analysis of the mRNA for HLA‐A*010 using reverse trancriptase‐polymerase chain reaction (RT‐PCR), with an allele‐specific 5′ primer in exon 2 (bp 253–271) and a series of 3′ primers in exons 3, 4 and 7 and in the 3′untranslated region, revealed that HCA‐7 contained a shortened message terminating in the region of the exon 3/4 boundary. The insertion of an extra cytosine in this region, which is only two bases from the exon 3/4 splice site, is presumed to lead to a splicing defect between exons 3 and 4 resulting in the lack of expression of a functional HLA‐A*0101 product. HCA‐7 is mismatch repair (MMR) defective due to lack of expression of hMLH1 resulting from hypermethylation of the promoter region. The consequential increase in errors in single‐nucleotide repeat stretches of DNA can account for the HLA‐A*0101 mutation. This has probably then been selected for in the tumour to enable escape from immune attack against an HLA‐A*0101‐restricted tumour‐specific determinant that has also arisen as a result of the tumour being MMR defective.
Identification of a new HLA‐B variant, HLA‐B*5615
Authors: Frison S. , Longhi E. , De Arias A.E. , Andreini E. , Scalamogna M. , Poli F.
Published: August 2005

Abstract:  A new HLA‐B allele, B*5615, has been identified in a Caucasian individual by sequence‐based typing. This allele shows a sequence identical to that of HLA‐B*5601 except for two nucleotide substitutions that cause a change from TTA to TAC at codon 116 and an amino acidic change from Leucine to Tyrosine in the mature protein.
Development and characterization of human constitutive proteasome and immunoproteasome subunit‐specific monoclonal antibodies
Authors: Bandoh N. , Ogino T. , Cho H.S. , Hur S.Y. , Shen J. , Wang X. , Kato S. , Miyokawa N. , Harabuchi Y. , Ferrone S.
Published: August 2005

Abstract:  Delta (Y), MB1 (X), and Z are the three catalytic β‐subunits located in the inner rings of the constitutive proteasome, an intracellular multicatalytic complex responsible for the generation of peptides presented by human leukocyte antigen (HLA) class I antigens to T cells. When cells are incubated with interferon‐γ, delta (Y), MB1 (X), and Z are replaced by LMP2, LMP7, and LMP10, respectively, leading to the expression of immunoproteasome which generates peptides with increased affinity for HLA class I antigens. The characterization of the expression of constitutive proteasome and immunoproteasome subunits in cells, normal tissues, and malignant lesions has been hampered by the lack or limited availability of constitutive proteasome and immunoproteasome subunit‐specific monoclonal antibodies (mAbs), which are suitable for immunohistochemical staining. To overcome this limitation, we generated human delta (Y), MB1 (X), Z, LMP2, LMP7, and LMP10‐specific mAb‐secreting hybridomas from BALB/c mice immunized with peptides and recombinant fusion proteins. The mAbs SY‐5, SJJ‐3, NB‐1, SY‐1, HB‐2, and TO‐7 were shown to be specific for delta (Y), MB1 (X), Z, LMP2, LMP7, and LMP10, respectively, as they react specifically with the corresponding molecules when tested with a human B lymphoid LG2 cell lysate in Western blotting and with the peptide derived from each molecule in enzyme‐linked immunosorbent assay. The reactivity of the six mAbs with the corresponding intracellular antigens resulted in intracellular staining when the mAbs were tested with microwave‐treated and saponin‐permeabilized cells in indirect immunofluorescence and with formalin‐fixed, paraffin‐embedded tissue sections in immunohistochemical reactions. These results suggest that the constitutive proteasome and immunoproteasome subunit‐specific mAbs we have developed are useful probes to characterize the expression of proteasome subunits in normal tissues and in pathological lesions.
Associations of major histocompatibility complex class I chain‐related molecule polymorphisms with Behcet's disease in Caucasian patients
Authors: Hughes E.H. , Collins R.W.M. , Kondeatis E. , Wallace G.R. , Graham E.M. , Vaughan R.W. , Stanford M.R.
Published: August 2005

Abstract:  HLA‐B*51 is known to be associated with Behcet's disease (BD) in many ethnic groups. The pathogenic gene, however, may lie close to the HLA‐B locus and therefore be in linkage disequilibrium with HLA‐B*51. On the basis of the proximity of MIC genes to HLA‐B, their expression pattern and their affinity for the activating NKG2D receptor on natural killer (NK) cells and γδ T cells, these molecules have been postulated as susceptibility factors in BD. DNA from 56 western European Caucasians with BD and 90 Caucasian controls were analysed by polymerase chain reaction using allele‐specific primers for MICA and MICB alleles. An increased allele frequency of MICA*009 was found in the BD patient group (25.0%) when compared with the controls (7.2%). This was associated with a corresponding decrease in MICA*008 in the BD patients (36.6%) compared with the controls (46.7%), which was not significant. MICA*009 was strongly associated with the presence of HLA‐B*51 in patients and controls. No significant difference in frequency of MICB alleles was found between patients and controls. Both

 HLA‐B*51 and MICA*009 are strongly associated with BD in a pure Caucasian BD patient group, and the two alleles are in linkage disequilibrium. No MICB allele was found to associate significantly with the disease, an unexpected finding considering the close proximity of the MICA and MICB loci. Our results suggest that while MICB does not influence the development of BD, polymorphisms in MICA may be pathogenic, perhaps through the interaction with NK and γδ T cells.
Difficult asthma in adults: recognition and approaches to management
Authors: Harrison B. D. W.
Published: August 2005

Abstract

Difficult asthma must be distinguished from severe asthma. It is then important in patients with suspected difficult asthma to ensure that the diagnosis is correct, and that if the patient has asthma that the attributed symptoms are indeed all genuinely due to the asthma and not to coexisting physical or psychogenic respiratory conditions. It is also important to be alert when there is discordance between symptoms and objective lung function in order to recognize both poor perceivers and over‐reactors. Difficult asthma can occur in patients with objectively mild, moderate or severe disease, but the consequences are most dramatic in patients with severe asthma. Asthma may be difficult for the patient, for the clinician or both because of disease factors, doctor or nurse therapist factors, and/or patient factors. Investigation requires access to the full range of respiratory, imaging and allergy tests. It also requires a multidisciplinary approach involving ear, nose and throat specialists and speech therapists, and access to psychiatric and psychological assessment and therapies. Poor compliance is associated with significantly poorer asthma and asthma‐related health outcomes. Poor compliance can be recognized in two‐thirds of such patients by their not attending scheduled appointments. Poor compliance is significantly associated with anxiety, social deprivation and adverse family circumstances, and these characteristics and adversities probably contribute to the poorly compliant behaviour. In difficult asthma it is important to identify and manage the condition causing the symptoms rather than prescribing more and more asthma therapy. Recognizing psychosocial adversity is essential. A structured approach is essential. There remains a small number of patients with genuine steroid‐resistant asthma, some with predominately neutrophilic rather than eosinophilic airway inflammation, and others for whom the secondary gain of continuing symptoms is overwhelming. There is a need for further research using agreed definitions, structured approaches and a full range of investigations in patients with difficult asthma. (Intern Med J 2005; 35: 543–547)
Glargine is superior to neutral protamine Hagedorn for improving glycated haemoglobin and fasting blood glucose levels during intensive insulin therapy
Authors: Fulcher G. R. , Gilbert R. E. , Yue D. K.
Published: August 2005

Abstract

Aim: To compare glycaemic control and symptomatic hypoglycaemia rates with glargine versus neutral protamine Hagedorn (NPH) in poorly controlled type 1 diabetes patients.

Methods: Patients (n = 125) received preprandial insulin lispro and either glargine (n = 62) or NPH (n = 63) at bedtime for 30 weeks in a multicentre, randomized, single‐blind (a blinded investigator made titration decisions) study. Basal insulin dosage was titrated to achieve fasting blood glucose (FBG) values <5.5 mmol/L.

Results:  Baseline characteristics were similar for the two groups (mean diabetes duration 17.5 ± 10.1 years) except mean glycated haemoglobin (HbA1c), which was lower in the glargine versus NPH group (9.2 ± 1.1% vs 9.7 ± 1.3%; P < 0.02). At end‐point, mean HbA1c was 8.3 versus 9.1% for the glargine versus NPH groups. Adjusted least‐squares mean (LSM) change from baseline was –1.04 versus –0.51%, a significant treatment benefit of 0.53% for HbA1c in favour of glargine (P < 0.01). Mean baseline FBG were similar for the glargine and NPH groups (11.2 vs 11.4 mmol/L). The means for end‐point FBG were 7.9 versus 9.0 mmol/L. Adjusted LSM change from baseline was –3.46 versus –2.34 mmol/L, with a significant difference of 1.12 mmol/L in favour of glargine (P < 0.05). There were similar total numbers of daytime mild, moderate or severe hypoglycaemia episodes in the two treatment arms. However, significantly fewer moderate or severe nocturnal hypoglycaemic episodes were observed in the glargine group (P = 0.04 and P = 0.02).

Conclusion:  Glargine is superior to NPH for improving HbA1c and FBG levels during intensive insulin therapy in patients with type 1 diabetes, and is associated with less severe nocturnal hypoglycaemia. (Intern Med J 2005; 35: 536–542)