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evidence for cyclophosphamide-induced gene conversion and mutation in mouse germ cells.cyclophosphamide (cp) is a widely used antineoplastic drug. it tests positive in several genotoxicity assays, including those with endpoints such as chromosomal aberrations in mammalian cells, mitotic recombination in drosophila melanogaster, and dominant lethal mutations in rodents. we have explored the effects of cp on genome stability of mouse (mus domesticus) spermatogenic cells, using a recombination-based transgenic assay called muscateer. in this system, intrachromosomal gene conversion e ...19979439729
sound pressure transformation at the pinna of mus domesticus.sound pressure transformation properties at the pinna of laboratory mice. mus domesticus, were studied by measuring the sound pressure level of continuous tone at a series of frequencies at the tympanic membrane as a function of the position of a sound source under free-field stimulation conditions. sound pressure transformation functions showed some prominent spectral notches throughout the frequency range of 10-80 khz tested. when delivered from some angles within the ipsilateral frontal hemis ...19979442865
effects of voluntary activity and genetic selection on aerobic capacity in house mice (mus domesticus).an animal model was developed to study effects on components of exercise physiology of both "nature" (10 generations of genetic selection for high voluntary activity on running wheels) and "nurture" (7-8 wk of access or no access to running wheels, beginning at weaning). at the end of the experiment, mice from both wheel-access groups were significantly lighter in body mass than mice from sedentary groups. within the wheel-access group, a statistically significant, negative relationship existed ...19989451619
population genetic structure in a robertsonian race of house mice: evidence from microsatellite polymorphism.genetic evidence was assessed for inbreeding and population subdivision in a robertsonian fusion (rb) race of the western european form of house mouse, mus musculus domesticus, in central belgium. inbreeding, and the factors responsible for subdivision (genetic drift and extinction-recolonization) can theoretically influence the fixation of underdominant rb variants. the data consisted of allele frequencies of eight microsatellite loci and of the rb(4.12) and rb(5.10) chromosomes. six population ...19989474776
live-borns from xx but not xy oocytes in the chimeric mouse ovary composed of b6.y(tir) and xx cells.when the y chromosome of some mus musculus domesticus subspecies is placed onto a c57bl/6j mouse background, the xy (b6.y(tir)) progeny develop only ovaries or ovotestes during fetal life. the xy sex-reversed female is infertile mainly because of death of embryos during preimplantation development. in the present study, we constructed female mouse chimera composed of b6.y(tir) and xx balb/c cells to determine whether developmental incompetence of xy oocytes can be attributed to defects in the oo ...19989475416
evolution of transcriptional regulatory elements within the promoter of a mammalian gene.transcription of the murine d7rp2e gene is highly variable among species of the genus mus, indicating that extensive modifications in the gene's regulatory elements have occurred during evolution. since promoter regions are well known to harbor cis-acting information that controls gene transcription, we compared the sequence and function of the d7rp2e promoter in several mus species, with the goal of understanding the molecular mechanisms underlying the interspecies variations in expression. thr ...19989501498
multiple copies of the ala-d gene are located at the lv locus in mus domesticus mice.incremental differences in delta-aminolevulinate dehydratase (ala-d; the second enzyme of the heme biosynthetic pathway) activity among inbred mouse strains can be attributed to variation in the number of copies of the ala-d gene. we have cloned and characterized the lv locus from an inbred mouse strain (dba/2j) that has three times the normal ala-d activity levels. the entire 12-kb ala-d gene plus 16 kb of flanking dna are found in 28-kb tandemly repeating units. we used the derived nucleotide ...19989521876
a description of the ontogeny of mouse agonistic behavior.the development of agonistic behavior was characterized in outbred swiss cd-1 male mus domesticus. at weaning (postnatal day [pnd] 21), mice were housed either individually or as male pairs. social encounters were carried out between dyads of initially unfamiliar same-age and same-housing subjects every 3rd day, from pnd 23 to 47. the majority of both offensive and defensive elements had their onset around pnd 29. overall, their expression increased around puberty (i.e., on pnd 35), which also r ...19989528111
pregnancy block in house mice (mus domesticus) as a function of t-complex genotype: examination of the mate choice and male infanticide hypotheses.pregnancy block, whereby recently mated female mice abort their pregnancies when exposed to novel (strange) males, was studied in house mice (mus domesticus) differing in t-complex genotype; t-mutations are deleterious and +/t females avoid +/t males as mates. the results of experiment 1, in which the genotype of the female, stud male, and strange male was systematically varied, showed that pregnancy block was most frequent when the strange male was +/+. because this effect was not enhanced amon ...19989528117
lymphocyte proliferative response in brown bears: cytokine role and glucocorticoid effect.lymphocyte stimulation and proliferation play a pivotal role in the immune response to soluble as well as to cellular, bacterial, and viral antigens. in this study, peripheral blood mononuclear cells (pbmc), mainly composed of lymphocytes, were separated by ficoll-hypaque density gradient centrifugation from 50-ml jugular vein blood samples drawn from six captive and five wild-caught brown bears (ursus arctos) (eight apennine brown bears from the italian population; three of undetermined origin) ...19989542157
decreased physical performance of congenic mice with mismatch between the nuclear and the mitochondrial genome.maternal transmission of mitochondrial dna (mtdna) allows us to generate mtdna congenic strain by repeating backcrosses of female mice to male mice of an inbred strain, which carries different mtdna haplotype from that of the female progenitor. since genetic backgrounds of inbred strains commonly used (e.g., c57bl/6j [b6] and balb/c) are mainly derived from an european subspecies of mus musculus domesticus, congenic strains, in which mtdna originated from an asian subspecies m. musculus musculus ...19989546205
[natural hybridization between two subspecies of the house mouse, mus musculus domesticus and mus musculus castaneus, near lake casitas, california].the house mouse mus musculus is a polytypic species, distributed worldwide, with three main subspecies: m. m. musculus in the north-east of eurasia, m. m. castaneus in south-east asia, and m. m. domesticus in europe, the near-east, and africa. this last subspecies may also be found in australia and the americas, where it was brought by european colonization. previous studies, however, have shown the presence of specific antiviral determinants of asian origin in a mouse population at lake casitas ...19989549063
prenatal and postnatal maternal effects on body weight in cross-fostering experiment on two subspecies of mice.a cross-fostering experiment was conducted on two quite distinct subspecies of mice, domesticated laboratory mouse of cf#1 (mus musculus domesticus) and yonakuni wild mouse (yk, mus musculus molossinus yonakuni), to estimate the prenatal and postnatal maternal effects on body weight of offspring. mating was done between subspecies, two or three females being mated to a male at nine-ten weeks of age. two dams of different subspecies that littered at the same day were used as a group of foster dam ...19989606419
evolution of a mammalian promoter through changes in patterns of transcription factor binding.previously, we identified evolutionarily derived changes in the pattern of nuclear factor binding to overlapping sites (termed a, b, and c, in proximal to distal order) within the promoter region of the murine d7rp2e gene. in mus domesticus, strong binding occurs at site b, with weak binding at sites a and c; in m. pahari, strong binding is observed at sites a and c, with weak binding at site b. the m. pahari-specific occupancy pattern is associated with repression of transcription. presently, w ...19989608046
proteins in urine scent marks of male house mice extend the longevity of olfactory signals.the binding of volatile semiochemicals to lipocalin proteins in many mammalian scent marks may provide a gradual release of volatile ligands, extending the life of airborne odour signals. we tested this by using menadione to displace semiochemical ligands from major urinary proteins (mups) in urine streaks obtained from adult male house mice, mus domesticus, and assessed the responses of other males to these and to intact urine marks as they aged. dominant male mice scent-mark their territories ...19989632512
genetically determined resistance to flavivirus infection in wild mus musculus domesticus and other taxonomic groups in the genus mus.inherited resistance to flaviviruses in laboratory mice is a rare trait conferred by an autosomal dominant gene (flvr). to provide information on genetic resistance to flaviviruses in wild mice, we analysed (i) wild m. m. domesticus trapped in australia, and (ii) mice representing other species and subspecies in the genus mus. mice were screened for resistance relative to c3h/hej mice by intracerebral challenge with murray valley encephalitis virus or yellow fever virus, and breeding studies wer ...19989638142
artificial selection for increased wheel-running behavior in house mice.replicated within-family selection for increased voluntary wheel running in outbred house mice (mus domesticus; hsd:icr strain) was applied with four high-selected and four control lines (10 families/line). mice were housed individually with access to activity wheels for a period of 6 days, and selection was based on the mean number of revolutions run on days 5 and 6. prior to selection, heritabilities of mean revolutions run per day (rev/day), average running velocity (rpm), and number of minut ...19989670598
recombination between subtypes creates a mosaic lineage of line-1 that is expressed and actively retrotransposing in the mouse genome.line-1, or l1, elements are retrotransposons that have amplified to high-copy number during the evolution of mammals. l1 appears to amplify in waves, spawning large numbers of progeny such that elements with distinct sequence features dominate the dispersal process in a given window of time. this process generates discrete subfamilies of l1 within mammalian genomes, with the oldest being remnants, or fossils, of earlier waves of amplification. in mice, at least three distinct subfamilies of l1 w ...19989677292
mhc-disassortative mating preferences reversed by cross-fostering.house mice (mus musculus domesticus) avoid mating with individuals that are genetically similar at the major histocompatibility complex (mhc). mice are able recognize mhc-similar individuals through specific odour cues. however, to mate disassortatively for mhc genes, individuals must have a referent, either themselves (self-inspection) or close kin (familial imprinting), with which to compare the mhc identity of potential mates. although studies on mhc-dependent mating preferences often assume ...19989718737
temporal changes in the frequency of colicinogeny in escherichia coli from house mice.escherichia coli was isolated from feral house mice (mus domesticus) during the course of a mouse plague in the state of victoria, australia. the isolates were characterized for the production of colicins and their resistance to the co-occurring colicins. of the 447 isolates examined, 59% were found to be colicinogenic. phenotypic and pcr-based genotypic methods were used to determine the types of colicins being produced. colicin e2 was the most common, representing 27% of the colicin-producing ...19989720045
wild isolates of murine cytomegalovirus induce myocarditis and antibodies that cross-react with virus and cardiac myosin.the laboratory-adapted k181 strain of murine cytomegalovirus (mcmv) induces both acute and chronic myocarditis, associated with autoantibodies to cardiac myosin, in susceptible balb/c mice. however, the k181 mcmv strain has been maintained in the laboratory for many years and may not resemble naturally occurring strains of mcmv in its ability to induce myocarditis. accordingly, six different isolates of mcmv from wild mus domesticus were compared with k181 mcmv for their ability to induce myocar ...19989741351
neuronal and behavioral differences between mus musculus domesticus (c57bl/6jby) and mus musculus castaneus (cast/ei).previous studies have demonstrated that classical inbred strains of laboratory mice do not exhibit large genetic distances when simple sequence repeats (ssrs) are used to test for their polymorphisms whereas mice from wild origin exhibit high polymorphisms (more than 90%) for these sequence when compared with classical inbred strains of laboratory mice. the difference between mus musculus castaneus and c57bl/6j reaches 98% and f1s male and female are fertile. these two properties pave the way fo ...19989754885
scent marks as reliable signals of the competitive ability of mates.the quality of an individual's odour can allow potential mates to discriminate against individuals of low social class, poor health status or unsuitable genotype. competitive scent marking provides a further mechanism which could allow mates to discriminate between individuals of apparently high quality. the presence or absence of fresh countermarks from competitors within an owner's territory or area marked by a dominant animal provides a reliable indicator of the owner's ability to defend its ...19989784223
olfactory preferences in two strains of wild mice, mus musculus musculus and mus musculus domesticus, and their hybrids.we studied olfactory preferences of two strains of mice, mus musculus musculus and mus musculus domesticus (considered here to be subspecies), and their hybrids, to examine the possible role of odours as a behavioural, premating mechanism that could explain the characteristics of their natural hybrid zone. we used a choice test with the bedding material of animals of the opposite sex from the animal tested and from both subspecies. male and female m. m. domesticus showed no preference either for ...19989787027
chromosomal heterozygosity and fertility in house mice (mus musculus domesticus) from northern italy.following the discovery of over 40 robertsonian (rb) races of mus musculus domesticus in europe and north africa, the house mouse has been studied extensively as an ideal model to determine the chromosomal changes that may cause or accompany speciation. current models of chromosomal speciation are based on the assumption that heterozygous individuals have a particularly low fertility, although recent studies indicate otherwise. despite their importance, fertility estimates for the house mouse ar ...19989799266
competitive behaviour in an island population of house mice, mus domesticus.because of the cryptic nature of small mammals inhabiting vegetation with widely scattered food resources, little is known about the behavioural mechanisms underlying their spatial dispersion. while house mice exploiting human-built environments attempt to exclude intruders aggressively from small territories that contain concentrated food resources, comparative tests show that the grassland mouse, m. spretus, establishes dominance relationships and then avoids sites used by dominant competitors ...19989819347
y chromosome variation of mice and men.dna sequences from the nonrecombining portion of the y chromosome were compared with autosomal and x-linked sequences from mice and humans to test the neutral prediction that ratios of polymorphism to divergence are the same for different genes. intraspecific variation within mus domesticus was compared with divergence between m. domesticus and mus caroli for sry, a region 5' to sry, and four x-linked genes, hprt, plp, amg, and glra2. none of these comparisons revealed significantly reduced vari ...19989866208
female sexual preferences differ in mus spicilegus and mus musculus domesticus: the role of familiarization and sexual experience.mating systems correspond to particular ecological conditions and result from proximate interactions between individuals. we compared the mating preferences of female mice of two species: the house mouse, mus musculus domesticus, and the mound-builder mouse, mus spicilegus. because of differences in their habitat, we expected to observe differences in their sexual preferences. we studied female preferences for a familiar or an unfamiliar male and the occurrence of copulation with the unfamiliar ...19989933543
energy cost of wheel running in house mice: implications for coadaptation of locomotion and energy budgets.laboratory house mice (mus domesticus) that had experienced 10 generations of artificial selection for high levels of voluntary wheel running ran about 70% more total revolutions per day than did mice from random-bred control lines. the difference resulted primarily from increased average velocities rather than from increased time spent running. within all eight lines (four selected, four control), females ran more than males. average daily running distances ranged from 4.4 km in control males t ...201010068627
ecg of the "newborn" mouse (mus domesticus) with specific reference to comparative av transmission.the objective of this study was to record the ecg of the smallest living mammal to extend the domain of data for comparative av nodal electrophysiologic purposes. these data are needed to establish the relationship between the pr interval and heart size in mammalian species of all sizes.199910090220
the cryptosporidium "mouse" genotype is conserved across geographic areas.a 298-bp region of the cryptosporidium parvum 18s rrna gene and a 390-bp region of the acetyl coenzyme a synthetase gene were sequenced for a range of cryptosporidium isolates from wild house mice (mus domesticus), a bat (myotus adversus), and cattle from different geographical areas. previous research has identified a distinct genotype, referred to as the "mouse"-derived cryptosporidium genotype, common to isolates from australian mice. comparison of a wider range of australian mouse isolates w ...199910203475
murine viruses in an island population of introduced house mice and endemic short-tailed mice in western australia.house mice (mus domesticus) were recently introduced to thevenard island, off the northwest coast of western australia. this island is also habitat for an endangered native rodent, the short-tailed mouse (leggadina lakedownensis). concerns have been raised that house mice may pose a threat to l. lakedownensis both through competition and as a source of infection. to assess the threat to l. lakedownensis posed by viral pathogens from m. domesticus, a serological survey was conducted from 1994 to ...199910231757
organisation of complex nuclear domains in somatic mouse cells.the number and associations of heterochromatin chromocenters, nucleoli, centromeres and telomeres were studied in the nucleus of different somatic cells of mus domesticus. fibroblasts of the cell line 3t3, kidney cells (primary culture), and bone marrow cells were used. the above mentioned nuclear and chromosome markers were identified by dapi/actinomycin d, indirect immunofluorescence with anti-centromere antibodies, silver impregnation for nucleolar proteins and fluorescence in situ hybridisat ...199910321023
mus and peromyscus chromosome homology established by fish with three mouse paint probes.fluorescence-labeled dna probes constructed from three whole house mouse (mus domesticus) chromosomes were hybridized to metaphase spreads from deer mouse (peromyscus maniculatus) to identify homologies between the species. mus chr 7 probe hybridized strongly to the ad-centromeric two-thirds of peromyscus chr 1q. most of mus 3 probe hybridized principally to two disjunct segments of peromyscus chr 3. mus chr 9 probe hybridized entirely to the whole peromyscus chr 7. three peromyscus linkage grou ...199910384049
use of the mhc for mate choice in wild house mice (mus domesticus).the mechanisms maintaining natural diversity at the major histocompatibility complex (mhc) are not well understood. to increase knowledge of one potential mechanism, i examined the use of mhc genes for mate choice by wild house mice in a controlled laboratory setting. three rearing groups of wild test mice were produced: non-fostered control mice, mice fostered into families of an inbred laboratory mouse strain, and mice fostered into families of a second, mhc-congenic mouse strain. mature test ...199810386390
crest staining of micronuclei from free-living rodents to detect environmental contamination in situ.in this work immunofluorescent antikinetochore (crest) staining was used to analyse bone marrow micronuclei (mn) from free-living animals belonging to four different rodent species. yellow-necked mice (apodemus flavicollis) and bank voles (clethrionomys glareolus) were trapped in the czech republic, algerian mice (mus spretus) in spain and house mice (mus musculus domesticus) in italy. animals were collected in areas displaying low or high environmental pollution in order to investigate the sens ...199910390506
induction of estrus in grouped female mice (mus domesticus) by synthetic analogues of preputial gland constituents.two major volatile constituents of the male mouse preputial gland, e,e-alpha-farnesene and e-beta-farnesene, were examined for their role in inducing estrous cycles in grouped female mice. the results indicated that the mixture of the farnesenes was as effective as the homogenate of the intact preputial gland, while the extract of the castrate preputial tissue did not show a pronounced response.199910400447
[characterization of a novel wild-type t(wmpi) haplotype of the house mouse (mus domesticus l.) from peru].data on molecular genetic analysis of the novel wild-type twmp1 haplotype found in a population of mus domesticus from peru are presented. complementation attribution of the novel haplotype as well as fertility of heterozygotes and transmission ratio distortion (trd) of the t-carrying chromosome in the progeny of the heterozygous males were studied. molecular analysis was carried out by means of blot hybridization with the four t-specific probes (tu48, tu66, tu119, and tu122). comparison of the ...199910420281
genetic variation and correlations between genotype and locomotor physiology in outbred laboratory house mice (mus domesticus).laboratory strains of house mice (mus domesticus) are increasingly used as model organisms in evolutionary physiology, so information on levels of genetic variation is important. for example, are levels of genetic variation comparable to those found in populations of wild house mice? we studied allozymes to estimate genetic variation in outbred hsd:icr mice, which have been used in several studies with evolutionary emphasis. the physiological significance of allozyme variation remains obscure. s ...199910425735
perception and recognition discriminated in the mouse auditory cortex by c-fos labeling.the functions of the fields of the mammalian auditory cortex in sound perception and recognition are unknown. we used fos (a protein of the inducible immediate-early gene c-fos) as a cellular marker of activated brain areas to show in the mouse (mus domesticus) that sound is processed differentially in auditory cortical fields according to its actual significance in a behavioral context. recognition, compared with perception of exactly the same sound, produced significantly less but well focused ...199910439460
artificial selection for increased wheel-running activity in house mice results in decreased body mass at maturity.to test the hypothesis that body size and activity levels are negatively genetically correlated, we conducted an artificial selection experiment for increased voluntary wheel-running activity in house mice (mus domesticus). here, we compare body masses of mice from control and selected lines after 14 generations of selection. in both groups, beginning at weaning and then for 8 weeks, we housed half of the individuals with access to running wheels that were free to rotate and the other half with ...199910460738
isolation and microinjection of somatic cell-derived mitochondria and germline heteroplasmy in transmitochondrial mice.at present, there are no means for creation of relevant animal models of human mitochondrial dna (mtdna)-based diseases in a directed fashion. as an initial step towards this end, we have developed a microinjection technique for transfer of isolated, viable mitochondria between two mouse species. previously, we reported detection, by nested pcr with species-specific primer sets, of mus spretus mtdna in mus musculus domesticus blastocyts following zygote microinjection and culture. we now report ...199910481311
whole body cholesterol, fat, and fatty acid concentrations of mice (mus domesticus) used as a food source.the concentrations of dry matter, cholesterol, saturated fat, monounsaturated fat, and 29 fatty acids were measured in four size categories of whole mice (mus domesticus) that are commonly fed to zoo animals. dry matter increased with age/size of mice, whereas cholesterol decreased with age/size. significant differences in fatty acid content were found among mice categories with capric, lauric, and myristic acids. mice categories had similar levels of palmitic, palmitoleic, heptadecenoic, steari ...199910484136
reduced nucleotide variability at an androgen-binding protein locus (abpa) in house mice: evidence for positive natural selection.previous work has shown that the gene for the alpha subunit of androgen-binding protein, abpa, may be involved in premating isolation between different subspecies of the house mouse, mus musculus. we investigated patterns of dna sequence variation at abpa within and between species of mice to test several predictions of a model of neutral molecular evolution. intraspecific variation among 10 mus musculus domesticus alleles was compared with divergence between m. m. domesticus and m. caroli for a ...199910486974
experimental trypanosomiasis of natural hybrids between house mouse subspecies.this study characterises the extent of the susceptibility to parasites (first demonstrated with helminths) of hybrids between mus musculus domesticus and mus musculus musculus. experimental infections with trypanosoma musculi of m. m. domesticus, m. m. musculus and their natural hybrids have been performed to compare their level of resistance/susceptibility. it appears that contrary to the results with helminths, hybrid mice present the same level of resistance/susceptibility to the trypanosome ...199910501611
contact zones between chromosomal races of mus musculus domesticus. 1. temporal analysis of a hybrid zone between the cd chromosomal race (2n=22) and populations with the standard karyotype.a temporal analysis of a hybrid zone between chromosomal races of mus musculus domesticus was performed to evaluate its dynamics over a 20-year period. the transect chosen was one previously analysed by spirito et al. (1980) across the hycbrid zone between the chromosomal race cd 2n=22 (central italy) and the surrounding populations with standard karyotype (2n=40). the results show that 20 years of hybridization have not had any significant effect on the position of this hybrid zone, nor on the ...199910504430
evolutionary rate of a gene affected by chromosomal position.genes evolve at different rates depending on the strength of selective pressure to maintain their function. chromosomal position can also have an influence [1] [2]. the pseudoautosomal region (par) of mammalian sex chromosomes is a small region of sequence identity that is the site of an obligatory pairing and recombination event between the x and y chromosomes during male meiosis [3] [4] [5] [6]. during female meiosis, x chromosomes can pair and recombine along their entire length. recombinatio ...199910508587
panel of microsatellite markers for whole-genome scans and radiation hybrid mapping and a mouse family tree.to facilitate whole-genome scan experiments, we selected a panel of 128 microsatellite markers on the basis of spacing and polymorphism in the strains dba/2, balb/c, akr, c57bl/6, c57bl/10, a/j, c3h, 129/j, sjl/j, jf1, and pwb. many of the primer pairs were redesigned for better performance. the last four strains were not characterized previously using these markers. jf1 and pwb are particularly interesting for intersubspecific crosses offering high polymorphism. we provide allele size data for ...199910508847
water and sodium requirements of field populations of house mice (mus domesticus) and short-tailed mice (leggadina lakedownensis) on thevenard island, in the arid pilbara region of western australia.the coexistence of the lakeland downs short-tailed mouse leggadina lakedownensis and house mouse mus domesticus on thevenard island, in the arid north of western australia, prompted a study to compare their seasonal water and sodium metabolism using tritiated water and sodium-22 as tracers. fractional water influx rates for m. domesticus (40.3 +/- 1.6% total body-water day-1) were significantly higher than those for l. lakedownensis (25.3 +/- 1.2% total body-water day-1). water effluxes were hig ...199910549142
the competing countermarks hypothesis: reliable assessment of competitive ability by potential mates.scent marking on top of (overmarking), or in the vicinity of, a scent mark already present is commonly termed countermarking. scent marks and countermarks provide a continuous record of competitive challenges between conspecifics, thus providing a reliable advertisement of an individual's ability to dominate or defend an area to other competitors and potential mates. to test the hypothesis that females should prefer males that countermark competing scent marks in their territory over those whose ...199910564605
fertility of y(tir).b6 sex-reversal females with xx orthotopic ovarian transplants.when the y chromosome of mus musculus domesticus (y(tir)) was introduced onto the c57bl/6j (b6) mouse background, testis development was impaired and half of the xy progeny (y(tir).b6) developed a female phenotype. y(tir).b6 fetal ovaries showed massive death of medullary oocytes and, after birth, produced abnormal levels of steroid hormones, exhibited irregular estrous cycles, and failed to become fertile. in this study we examined whether alterations during perinatal development observed in y( ...199910569985
sex reversal caused by mus musculus domesticus y chromosomes linked to variant expression of the testis-determining gene sry.when the y chromosomes from certain populations of mus musculus domesticus are introduced into the mouse strain c57bl/6 (b6), testis determination can fail, resulting in gonads developing either as ovotestes (with both ovarian and testicular components) or as ovaries. not all y(dom) chromosomes cause sex reversal. y(dom) chromosomes are divided into three classes based upon their ability to induce testes in b6. the molecular basis underlying the three y(dom) classes is an enigma. the simplest ex ...199910588871
unravelling the chemical basis of competitive scent marking in house mice.major urinary proteins (mups) in the urine of male house mice, mus domesticus, bind the male signalling volatiles 2- sec -butyl-4,5-dihydrothiazole (thiazole) and 3,4-dehydro- exo -brevicomin (brevicomin) and slowly release these volatiles from urinary scent marks. to examine the role of urinary proteins and volatiles, either attached or unattached to the proteins, in competitive scent marking, we fractionated urine from isolated male balb/c laboratory mice, mus musculus, by size-exclusion chrom ...199910600138
behaviour of house mice artificially selected for high levels of voluntary wheel running.we have developed a novel model to study the correlated evolution of behavioural and morphophysiological traits in response to selection for increased locomotor activity. we used selective breeding to increase levels of voluntary wheel running in four replicate lines of laboratory house mice, mus domesticus, with four random-bred lines maintained as controls. the experiment presented here tested for correlated behavioural responses in the wheel-cage complex, with wheels either free to rotate or ...199910600154
an axonemal dynein at the hybrid sterility 6 locus: implications for t haplotype-specific male sterility and the evolution of species barriers.poor sperm motility characterized by a distinct aberration in flagellar waveform known as "curlicue" is a hallmark of t haplotype (t) homozygous male sterility. previous studies have localized "curlicue" and a flagellar developmental defect, "whipless", to the hybrid sterility 6 locus (hst6), between the markers pim1 and crya1. more recent heterospecific breeding experiments between mus spretus (spretus) and mus musculus domesticus (domesticus) have mapped the primary source(s) of both "curlicue ...200010602986
the origin of a robertsonian chromosomal translocation in house mice inferred from linked microsatellite markers.the western european house mouse, mus domesticus, includes many distinct robertsonian (rb) chromosomal races. two competing hypotheses may explain the distribution of rb translocations found in different populations: they may have arisen independently multiple times, or they may have arisen once and been spread through long-distance dispersal. we investigated the origin of the rb 5.15 translocation using six microsatellite loci linked to the centromeres of chromosomes 5 and 15 in 84 individuals ...199910605117
water and sodium balances and metabolic physiology of house mice (mus domesticus) and short-tailed mice (leggadina lakedownensis) under laboratory conditions.a laboratory study investigated the metabolic physiology, and response to variable periods of water and sodium supply, of two arid-zone rodents, the house mouse (mus domesticus) and the lakeland downs short-tailed mouse (leggadina lakedownensis) under controlled conditions. fractional water fluxes for m. domesticus (24 +/- 0.8%) were significantly higher than those of l. lakedownensis (17 +/- 0.7%) when provided with food ad libitum. in addition, the amount of water produced by m. domesticus and ...199910633560
breast cancer incidence highest in the range of one species of house mouse, mus domesticus.incidence of human breast cancer (hbc) varies geographically, but to date no environmental factor has explained this variation. previously, we reported a 44% reduction in the incidence of breast cancer in women fully immunosuppressed following organ transplantation (stewart et al (1995) lancet 346: 796-798). in mice infected with the mouse mammary tumour virus (mmtv), immunosuppression also reduces the incidence of mammary tumours. dna with 95% identity to mmtv is detected in 40% of human breast ...200010646903
spontaneous mutation in the db gene results in obesity and diabetes in cd-1 outbred mice.five allelic mutants of the diabetes (db) gene have been previously described in mice and rats causing obesity, infertility, and varying degrees of diabetes. we have identified a new, spontaneous mutation resulting in obesity and diabetes in a colony of cd-1 outbred mice, mus musculus domesticus. genetic complementation studies indicated that the new mutation was an allele of the diabetes locus. sequence analysis of cdna fragments showed a deletion of one g residue located in exon 12 of the lept ...200010666131
both nuclear and cytoplasmic components are defective in oocytes of the b6.y(tir) sex-reversed female mouse.in the mammalian gonadal primordium, activation of the sry gene on the y chromosome initiates a cascade of genetic events leading to testicular organization whereas its absence results in ovarian differentiation. an exception occurs when the y chromosome of mus musculus domesticus from tirano, italy (y(tir)), is placed on the c57bl/6j (b6) genetic background. the b6.y(tir) progeny develop only ovaries or ovotestes despite sry transcription in fetal life. consequently, the xy offspring with bilat ...200010694422
male-male competition magnifies inbreeding depression in wild house mice.the detrimental effects of inbreeding on vertebrates are well documented for early stages of the life cycle in the laboratory. however, the consequences of inbreeding on long-term survival and reproductive success (darwinian fitness) are uncertain for vertebrates in the wild. here, we report direct experimental evidence for vertebrates that competition increases the harmful effects of inbreeding on offspring survival and reproduction. we compared the fitness of inbred (from full-sib matings) and ...200010716731
gene flow of unique sequences between mus musculus domesticus and mus spretus.allelic diversity has been examined from a variety of mus musculus subspecies and mus spretus strains by sequencing at a 453-bp unique sequence locus. one m. m. domesticus classic inbred strain, c57bl/ksj, contained a sequence identical to that in the m. spretus wild-derived inbred strain seg, and other wild m. spretus isolates. such a result should have been precluded by the expected divergence between the species unless there has been interspecies gene flow. examination of c57bl/ksj for m. spr ...200010723728
line-1 (l1) lineages in the mouse.recently, a rapidly amplifying family of mouse line-1 (l1) has been identified and named t(f). the evolutionary context surrounding the derivation of the t(f) family was examined through phylogenetic analysis of sequences in the 3' portion of the repeat. the mus musculus domesticus t(f) family was found to be the terminal subfamily of the previously identified l1md4 lineage. the l1md4 lineage joins the other prototypical mouse line-1 lineage (the l1mda2 lineage) approximately 1 mya at about the ...200010742052
complete repopulation of mouse mitochondrial dna-less cells with rat mitochondrial dna restores mitochondrial translation but not mitochondrial respiratory function.by the fusion of mtdna-less (rho(0)) cells of mus musculus domesticus with platelets from different species, mtdna repopulated cybrids were obtained for finding the mtdna species that could induce mitochondrial abnormalities. expression of mitochondrial dysfunction might be expected in these cybrids due to incompatibility between nuclear and mitochondrial genomes from different species. the results showed that mouse rho(0) cells could receive mtdna from a different mouse species, m. spretus, or ...200010790404
a new family of genes and pseudogenes potentially expressing testis- and brain-specific leucine zipper proteins in man and mouse.we have characterized a new mouse gene highly transcribed in the testis, and a derived intronless gene expressed in the embryo. the latter gene is present in mus musculus domesticus and in mus musculus castaneus but is absent in mus spretus. the sequencing of different clones from a testis cdna library reveals a complex transcriptional regulation for the intron-containing gene. the use of several promoters, alternative splicing and trans-splicing, and of two different polyadenylation sites accou ...200010831844
body temperatures of house mice artificially selected for high voluntary wheel-running behavior: repeatability and effect of genetic selection.we studied rectal body temperatures of house mice (mus domesticus) that had been artificially selected for high voluntary wheel running.1. at generation 17, mice from the four replicate selected lines ran, on average, 2.5-times as many revolutions/day as did mice from the four random-bred control lines.2. during the day, repeatability of individual differences in body temperature measured 4 days apart was low; at night, repeatability was statistically significant across three time scales (1 day, ...200010838179
effect of somatostatin on electrogenic ion transport in the duodenum and colon of the mouse, mus domesticus.in this study, we have used the mouse intestine and the ussing short circuit technique to compare the effects and mechanism of action of somatostatin (sst, 0.1 microm) on camp- and ca(2+)-mediated ion secretion in the duodenum and colon of the swiss-webster mouse. the camp-dependent secretagogues, prostaglandin e(2) (1 microm) and dibutyryl-camp (150 microm) increased short circuit current (i(sc)) in both regions, but only the colonic response was inhibited by sst. this inhibition was independen ...200010840221
mitochondrial dna and chromosomal studies of wild mice (mus) from turkey and iran.complete d-loop sequences of 20 mus from three localities in turkey and seven in iran were characterized. these countries are thought to be close to the place of origin of the subspecies mus musculus domesticus. five new m. m. domesticus haplotypes were added to the nine already known for the region. four of these 14 haplotypes were very similar to the consensus d-loop sequence for western europe defined by nachman et al. (1994), which may represent the ancestral condition for m. m. domesticus. ...200010849070
conspecific and heterospecific behavioural discrimination of individual odours by mound-building mice.we have tested the ability of male mound-building mice, mus spicilegus, to discriminate on the basis of their social odours a) two males of their own species; and b) two males of the house mouse, mus musculus domesticus. an habituation-dishabituation procedure was used. an experimental animal was presented with the scent from the same stimulus animal for four trials; on the fifth trial, scent from a second stimulus animal was presented. male mus spicilegus were able to discriminate the olfactory ...199810877600
non-random distribution of the pericentromeric heterochromatin in meiotic prophase nuclei of mammalian spermatocytes.the central or peripheral distribution of condensed chromatin (cc) was studied in pachytene spermatocyte nuclei in mus domesticus, 2n = 40; pudu puda, 2n = 70; ctenomys opimus, 2n = 26 and octodon degus, 2n = 58. species were chosen according to the morphological characteristics of their chromosomal complements and in particular, the terminal or medial chromosomal localisation of the pericentromeric constitutive heterochromatin. counts were made by defining the areas corresponding to peripheral ...199910897793
functional constraints of nuclear-mitochondrial dna interactions in xenomitochondrial rodent cell lines.the co-evolution of nuclear and mitochondrial genomes in vertebrates led to more than 100 specific interactions that are crucial for an optimized atp generation. these interactions have been examined by introducing rat mtdna into mouse cells devoid of mitochondrial dna (mtdna). when mtdna-less cells derived from the common mouse (mus musculus domesticus) were fused to cytoplasts prepared from mus musculus, mus spretus, or rat (rattus norvegicus), a comparable number of respiring clones could be ...200010908562
defective mesonephric cell migration is associated with abnormal testis cord development in c57bl/6j xy(mus domesticus) mice.during the critical period of mouse sex determination, mesenchymal cells migrate from the mesonephros into the adjacent developing testis. this process is thought to initiate cord development and is dependent on sry. the presence of sry, however, does not always guarantee normal testis development. for example, transfer of certain mus domesticus-derived y chromosomes, i.e., m. domesticus sry alleles, onto the c57bl/6j (b6) inbred mouse strain results in abnormal testis development. we tested the ...200010964462
nesting behavior of house mice (mus domesticus) selected for increased wheel-running activity.nest building was measured in "active" (housed with access to running wheels) and "sedentary" (without wheel access) mice (mus domesticus) from four replicate lines selected for 10 generations for high voluntary wheel-running behavior, and from four randombred control lines. based on previous studies of mice bidirectionally selected for thermoregulatory nest building, it was hypothesized that nest building would show a negative correlated response to selection on wheel-running. such a response c ...200010979598
learning to cope with two different food distributions: the performance of house mice (mus musculus domesticus).search abilities of mice (mus musculus domesticus) were evaluated using an arena closed by a ceiling in which 9 food sources (which mice could reach standing on their hind legs) could be arranged according to 2 configurations: a 3 x 3 square matrix and 3 clusters each containing 3 food sources. testing conditions prevented olfactory and visual cues from being left after visits to food sources, and mice were able to choose alternative routes between food sources. results showed that mice were mor ...200010994843
detection of quantitative trait loci for body weight at 10 weeks from philippine wild mice.a genome-wide scan for quantitative trait loci (qtls) controlling body weight at 10 weeks after birth was carried out in a population of 387 intersubspecific backcross mice derived from a cross between c57bl/6j inbred mice (mus musculus domesticus) and wild mice (m. m. castaneus) captured in the philippines, in order to discover novel qtls from the wild mice that have about 60% lower body weight than c57bl/6j. by interval mapping, we detected four qtls: a highly significant qtl on chromosome (ch ...200011003694
effects of voluntary activity and genetic selection on muscle metabolic capacities in house mice mus domesticus.selective breeding is an important tool in behavioral genetics and evolutionary physiology, but it has rarely been applied to the study of exercise physiology. we are using artificial selection for increased wheel-running behavior to study the correlated evolution of locomotor activity and physiological determinants of exercise capacity in house mice. we studied enzyme activities and their response to voluntary wheel running in mixed hindlimb muscles of mice from generation 14, at which time ind ...200011007602
mhc-mediated fetal odourtypes expressed by pregnant females influence male associative behaviour.mice can recognize one another by individually characteristic phenotypic body odours (odourtypes) that reflect their genetic constitution at the highly polymorphic major histocompatibility complex (mhc) of genes on chromosome 17. we have shown previously that mhc-determined odours are produced by fetuses: house mice, mus domesticus, can be trained to discriminate between genetically identical pregnant females carrying 9-18-day-old fetuses of differing mhc type. theoretically, it should be possib ...200011007637
intestinal nutrient uptake measurements and tissue damage: validating the everted sleeves method.the reliability of methods for nutrient uptake measurements across the intestinal epithelium relies on the integrity of the mucosal epithelium and the enterocytes. we tested effects of tissue handling during the "everted sleeves method" on the length of intestinal villi, the surface magnification, the circumference of the gut, and the thickness of the muscle layer in sunbirds (nectarinia osea), chicken (gallus gallus), and mice (mus domesticus). the sunbird has thin and delicate intestinal villi ...200011009399
contact zone between chromosomal races of mus musculus domesticus. 2. fertility and segregation in laboratory-reared and wild mice heterozygous for multiple robertsonian rearrangements.litter size, anaphase i nondisjunction and x-y dissociation at metaphase i were studied in homozygous and heterozygous house mice from a central italian chromosomal hybrid zone between the cd (2n=22) race and the standard race (2n=40). we also observed the segregation of the two chromosomal forms (robertsonian and non-robertsonian) in male and female multiple heterozygotes from the karyotype of their offspring and chromosomal arm counts of metaphase ii. litter size was significantly reduced in t ...200011012717
selective and continuous elimination of mitochondria microinjected into mouse eggs from spermatids, but not from liver cells, occurs throughout embryogenesis.exclusion of paternal mitochondria in fertilized mammalian eggs is very stringent and ensures strictly maternal mtdna inheritance. in this study, to examine whether elimination was specific to sperm mitochondria, we microinjected spermatid or liver mitochondria into mouse embryos. congenic b6-mt(spr) strain mice, which are different from c57bl/6j (b6) strain mice (mus musculus domesticus) only in possessing m. spretus mtdna, were used as mitochondrial donors. b6-mt(spr) mice and a quantitative p ...200011063701
a comparative study of parental care between two rodent species: implications for the mating system of the mound-building mouse mus spicilegus.paternal care is uncommon in mammals where males are more often involved in sexual competition than in providing care for their own offspring. however some species present some form of paternal care and, most of the time, this phenomenon is associated with a monogamous mating system. mice of the genus mus, such as the house mouse mus musculus domesticus, are commonly considered to be polygamous-polygynous species. in mus spicilegus, the mound-building mouse, previous results on female sexual pre ...200011074310
ultrasonic vocalization by female mice in the presence of a conspecific carrying food cues.in female mice, mus domesticus, reunion with a same-sex conspecific is associated with intense ultrasonic vocalization. we examined whether the palatability of a familiar food eaten by a demonstrator mouse and the motivational state of the conspecific observer could modulate the number of ultrasonic calls uttered during female-female interaction in nmri mice. a pilot study indicated that these calls were uttered almost exclusively by the observer member of the pair. observers were either food de ...200011082239
spontaneous occurrence of a robertsonian fusion involving chromosome 19 by single whole-arm reciprocal translocation (wart) in wild-derived house mice.chromosomal races of the house mouse (mus musculus domesticus) bear robertsonian (rb) fusions, which consist of centric translocations between two non-homologous acrocentric chromosomes. the high level of diversity of these fusions in house mice is generated by de-novo formation of rb fusions and subsequent whole-arm reciprocal exchanges (warts). this paper describes the spontaneous occurrence of a new rb fusion, rb(4.19), in progeny of wild-derived house mice segregating for rb(4.12). the chrom ...200011117355
structural complexity of territories: preference, use of space and defence in commensal house mice, mus domesticus.previous studies suggest the physical structure of a habitat has profound effects on intraspecific competition and spacing behaviour among small mammals. we compared habitat preferences and the exploratory behaviour and aggressive territorial defence of male house mice in three types of enclosure differing only in their degree of structural complexity. each enclosure contained a nestbox placed in one corner, a central food hopper and 10 house bricks. the bricks were either placed around the oute ...200011124874
genome organization and phylogenetic distribution of a novel family of ancient murine endogenous proviruses with evidence for transposition-mediated proliferation.a new family of murine endogenous proviruses (vl6.0) is described here. the intact provirus is near 6 kb in length and shows a genomic organization of 5' ltr, gag, pol, env, and 3' ltr. the primer binding site (pbs) is that of a trna(gly). the lack of functional open reading frames and occurrence of significant gaps in most, if not all, members of this group show it to be ancient. our estimate of copy number per haploid genome is 30+. members of this group have been isolated from mus musculus do ...200011131339
attractivity and social preferences in mice (mus musculus domesticus): the role of prepubertal sexual segregation and of precocious weaning.mice (mus musculus domesticus) were raised (postnatal day 15 to 25) in single- or mixed-sex litters and precociously (day 15) or regularly (day 25) weaned. when they were faced as adults with a basic social choice--between two stimulus mice raised in litters of different sex composition but both of the same sex as the chooser--mice raised in mixed-sex litters were preferred. in the sociosexual choice-between a male and a female, both from the single- or the mixed-sex group--the opposite-sex pref ...200011149536
prey targeting by the infrared-imaging snake python molurus: effects of experimental and congenital visual deprivation.boid and crotaline snakes possess two distinct types of organ evolved to image radiant electromagnetic energy: the lateral eye, which responds to visible light, and the pit organ, which responds to infrared radiation. while infrared imaging may allow accurate predatory targeting in complete absence of visual information, both infrared and visual information are probably normally involved in prey targeting. we examined the roles of vision and infrared imaging in python molurus predatory performan ...200111164522
susceptibility of natural hybrids between house mouse subspecies to sarcocystis muris.a previous study showed that the susceptibility of hybrids between two mus musculus musculus and mus musculus domesticus did not apply to every parasite. the authors proposed that only parasites which exerted enough constraints would induce the selection of poorly compatible systems of resistance in the subspecies. this study completes the previous work. experimental infections of mice of the two subspecies and their hybrids with the tissue-dwelling protozoan sarcocystis muris show that hybrids ...200111165266
[new discoveries in experimental cancer].this 7th international symposium organized by the national academy of medicine on new directions in cancer management, was sponsored by iucc (international union against cancer) and received important financial assistance from the fritz bender foundation. in 1996 and 97, the first two symposia also dealt with cancer, specifically with tumor immunology and with the relation of human breast cancer with mmtv (murine mammary tumor virus). the aim of these introductory remarks is to emphasize recent ...200011188923
the prevalence of viral antibodies during a large population fluctuation of house mice in australia.we studied the seroprevalence of three viruses (mouse cytomegalovirus (mcmv), minute virus of mice (mvm), and mouse parvovirus (mpv)) in house mice (mus domesticus) in 1995 7. in the first year average mouse density was less than 1 mouse/ha. from november 1995 to may 1996 the population increased at an average rate of 7% per week, a doubling time of about 10 weeks. from august 1996 to may 1997 the population increased at an average rate of 10% per week, a doubling time of about 7.5 weeks. from a ...200011218223
maximum cold-induced food consumption in mice selected for high locomotor activity: implications for the evolution of endotherm energy budgets.we studied house mice (mus domesticus) that had been artificially selected for high activity to test the hypothesis that a high capacity for energy assimilation in cold-exposed endotherms could evolve as a correlated response to selection for increased locomotor activity. after 10 generations of selection for increased voluntary wheel-running, mice from four selected lines ran 75 % more wheel revolutions per day than did mice from four random-bred, control lines. the maximum cold-induced rates o ...200111222133
urine marking and social dominance in male house mice (mus musculus domesticus).house mice use urine marking for a variety of forms of social communication. urine marking varies with dominance status; socially dominant male house mice urine mark more than those that are socially subordinate. experiment i was designed to confirm this previous finding. experiment ii was designed to test whether urine marking, measured prior to testing males for aggression, could be used to predict social dominance. mice were tested for urine marking in 20 cmx40 cm rectangular cages with filte ...200111254998
clinal analysis of a chromosomal hybrid zone in the house mouse.these studies centre on the 'barcelona' karyotypic race of the western house mouse (mus musculus domesticus), first described by adolph & klein (1981). this is one of many races within m. m. domesticus characterized by metacentric chromosomes that have originated by repeated robertsonian fusions, with perhaps further modification by whole-arm reciprocal translocations. data on 111 mice from 20 sites show that the race is centred 24 km to the west of barcelona city and has a homozygous metacentri ...200111279829
gallegostrongylus australis n. sp. (nematoda: angiostrongylidae) from muridae in australia, with zoogeographical considerations.gallegostrongylus australis n. sp. (nematoda: angiostrongylidae) is described from subpleural nodules in the lungs of rattus fuscipes, r. lutreolus and mus domesticus in australia. it is distinguished from g. andersoni occurring in gerbillids in west africa by the shorter lengths of spicules and gubernaculum, and from g. ibicensis occurring in microtids and murids in spain by the greater lengths of spicules and gubernaculum and the shorter distances from vulva and from anus to the caudal extremi ...200111304950
female preference for male saliva: implications for sexual isolation of mus musculus subspecies.we studied the effects of a single genetic change on a complex mammalian behavior using animals congenic for two variants of abpa, the gene for the alpha subunit of mouse salivary androgen-binding protein (abp), in two-way preference tests. females exhibited a preference for investigating salivas of males of their own genetic type of abp but not for urines of either type of male. this preference behavior is consistent for samples of mice from geographically diverse populations of mus musculus do ...200111327170
patterns of infection by salmonella and yersinia spp. in commensal house mouse (mus musculus domesticus) populations.this study sought to examine the risk posed by house mice transmitting pathogens to livestock on typical mixed-agriculture farms in the uk.200111348436
low levels of sry transcripts cannot be the sole cause of b6-y(tir) sex reversal.sry, a single-copy gene on the y-chromosome, triggers the fetal gonad to begin testis differentiation in mammals. on the other hand, mutation or absence of sry results in ovary differentiation and the female phenotype. however, cases of xy sex reversal in the presence of wild-type sry exist in mice and man. one such example is the b6-y(tir) mouse, whose autosomes and x-chromosome are from the c57bl/6j mouse (an inbred strain of mus musculus molossinus), whereas the y-chromosome is from a mus mus ...200111353512
rodents and leptospira transmission risk in terceira island (azores).the role of rodents as leptospira renal carriers in terceira island was evaluated (1993-1995) through kidney culture and serology [microscopic aglutination test (mat)] of 94 mice and rats. fifty-nine animals were positive (n = 41 by serology + culturing; n = 11 serology; n = 7 culturing), presenting a wide distribution in man-made and natural areas. house mice had the highest bacteriological (82.9%) and serological (90.9%) rates, being strictly related to serovar arborea. black rats were involve ...200011484805
reproductive changes in fluctuating house mouse populations in southeastern australia.house mice (mus domesticus) in the victorian mallee region of southeastern australia show irregular outbreaks. changes in reproductive output that could potentially drive changes in mouse numbers were assessed from 1982 to 2000. litter size in females is positively correlated with body size. when standardized to an average size female, litter size changes seasonally from highest in spring to lowest in autumn and winter. litter size is depressed throughout breeding seasons that begin when the abu ...200111506689
c57bl/6j-t-associated sex reversal in mice is caused by reduced expression of a mus domesticus sry allele.c57bl/6j-t-associated sex reversal (b6-tas) in xy mice results in ovarian development and involves (1) hemizygosity for tas, a gene located in the region of chromosome 17 deleted in t(hp) and t(orl), (2) homozygosity for one or more b6-derived autosomal genes, and (3) the presence of the akr y chromosome. here we report results from experiments designed to investigate the y chromosome component of this sex reversal. testis development was restored in b6 t(orl)/+ xy(akr) mice carrying a mus muscu ...200111514455
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