| trichostrongylina (nematoda) parasitic in phyllotis sp. (rodentia: sigmodontinae) from argentina, with description of three new species. | the trichostrongylina parasitic in the leaf-eared mouse phyllotis sp. (sigmodontinae) from the province of catamarca, argentina are studied. three new species of stilestrongylus freitas, lent and almeida, 1937 (heligmosomoidea: heligmonellidae: nippostrongylinae) are described. stilestrongylus andalgala n. sp. is distinguished from the most closely related species s. moreli diaw, 1976 parasitic in auliscomys boliviensis from bolivia, by the absence of a common trunk of right rays 2 and 3, by lef ... | 2007 | 17129752 |
| two new species of nippostrongylinae (nematoda: trichostrongylina: heligmonellidae) from the grey leaf-eared mouse graomys griseoflavus (sigmodontinae) in argentina. | two new species of nippostrongylinae, hassalstrongylus puntanus n. sp., and stilestrongylus franciscanus n. sp. are described from the intestine of the grey leaf-eared mouse graomys griseoflavus (waterhouse, 1837) (sigmodontinae) from the province of san luis, argentina. hassalstrongylus puntanus n. sp. is distinguished from the most closely related species h. dollfusi (díaz-ungría, 1963), a parasite of mus musculus from venezuela by longer rays 2, shorter rays 4, proximal half of the dorsal ray ... | 2003 | 12669346 |
| phylogenetic relationships among robertsonian karyomorphs of graomys griseoflavus (rodentia, muridae) by mitochondrial cytochrome b dna sequencing. | graomys griseoflavus (waterhouse 1837) is a phyllotine murid rodent with a robertsonian autosomal polymorphism, having been described 2n = 42, 41, 38, 37, 36, 35 and 34 karyomorphs, and proposed a chromosomal divergence pathway accounted by four sequential robertsonian fusions. sequences of a fragment (422 bp long) of the cytochrome b (cyt b) mitochondrial gene and its 5' flanking region (trna glu) were obtained for 19 graomys griseoflavus from different karyomorphs to infer phylogenetic relatio ... | 2002 | 12369098 |
| thermal freedom of graomys griseoflavus in a seasonal environment. | 1. thermal freedom, defined as the physiological potential to make full spatiotemporal use of the seasonal thermal macroclimate, was assessed in graomys griseoflavus, a cricetid rodent inhabiting the chaco province in argentina. 2. the extent of the physiological thermal range (58 degrees c) was larger than the seasonal thermal range (30-50 degrees c), favoring graomys resistance to low winter temperatures. the upper physiological thermal limit was almost coincident with the highest extreme of s ... | 1987 | 2886267 |
| molecular analysis of chromosomal polymorphism in the south american cricetid, graomys griseoflavus. | graomys griseoflavus is a south american phyllotine rodent widespread in argentina that shows a high frequency of robertsonian fusions (rfs). dna restriction with ecori produced a 250-bp repeated family (eg250) specific for the genus. southern hybridization and sequencing analysis indicate that the eg250 family is heterogeneous, comprising at least two subfamilies. in situ hybridized eg250 probe showed a centromere location in almost all chromosomes. in all karyomorphs c-banding was negative, bu ... | 1995 | 7551551 |
| autosomal rearrangements in graomys griseoflavus (rodentia): a model of non-random robertsonian divergence. | the south american rodent graomys griseoflavus exhibits a remarkable chromosome polymorphism as a consequence of four robertsonian fusions. focusing on the genetic analysis of the taxon, genome organization of all karyomorphs was studied at chromosome and molecular organization level. cytogenetic (g, nor and re banding) and molecular (satellite and mitochondrial dnas) events accompanying chromosome divergence allowed tracing a phylogenetic relationship among all karyomorphs. available data led t ... | 2003 | 15061797 |
| spermatocyte apoptosis, which involves both intrinsic and extrinsic pathways, explains the sterility of graomys griseoflavus x graomys centralis male hybrids. | spermatogenic impairment and the apoptotic pathways involved in establishing sterility of male hybrids obtained from crossing graomys griseoflavus females with graomys centralis males were studied. testes from g. centralis, g. griseoflavus and hybrids were compared at different ages. terminal transferase-mediated dutp nick-end labelling assay (tunel), fas, bax and cytochrome c labelling were used for apoptosis evaluation, and calbindin d(28k) staining as an anti-apoptotic molecule. in 1-month-ol ... | 2010 | 20047733 |
| association of cellular and molecular alterations in leydig cells with apoptotic changes in germ cells from testes of graomys griseoflavus×graomys centralis male hybrids. | spermatogenesis is disrupted in graomys griseoflavus×graomys centralis male hybrids. this study was aimed to determine whether morphological alterations in leydig cells from hybrids accompany the arrest of spermatogenesis and cell death of germ cells and whether apoptotic pathways are also involved in the response of these interstitial cells. we used three groups of 1-, 2- and 3-month-old male animals: (1) g. centralis, (2) g. griseoflavus and (3) hybrids obtained by crossing g. griseoflavus fem ... | 2014 | 24894511 |
| management of protected areas and its effect on an ecosystem function: removal of prosopis flexuosa seeds by mammals in argentinian drylands. | the ecological function of animal seed dispersal depends on species interactions and can be affected by drivers such as the management interventions applied to protected areas. this study was conducted in two protected areas in the monte desert: a fenced reserve with grazing exclusion and absence of large native mammals (the man and biosphere ñacuñán reserve; fr) and an unfenced reserve with low densities of large native and domestic animals (ischigualasto park; ufr). the study focuses on prosop ... | 2016 | 27655222 |
| patterns of evolution in graomys griseoflavus (rodentia, cricetidae). i. protein polymorphism in populations with different chromosome numbers. | protein polymorphism has been studied by means of starch gel electrophoresis of tissue extracts in three population samples of graomys griseoflavus collected at different sites in central-west argentina. individuals from two of the samples had chromosomal number 2n = 42 and those from the other sample, 2n = 38, 37 or 36. a total of 28 loci were analyzed. high levels of variability were observed in three samples (p ranging between 0.46 and 0.66; h (epsilon) from 0.160 to 0.188). genetic distance ... | 1994 | 7928387 |
| distribution of telomeric sequences (ttaggg)n in rearranged chromosomes of phyllotine rodents (cricetidae, sigmodontinae). | phyllotines are sigmodontine rodents endemic to south america with broad genetic variability, robertsonian polymorphisms being the most frequent. moreover, this taxon includes a species with multiple sex chromosomes, which is infrequent in mammals. however, molecular cytogenetic techniques have never been applied to phyllotines to elucidate their karyotypic evolution. we studied the chromosomes of 4 phyllotine species using fish with a pantelomeric probe (ttaggg)n. graomys griseoflavus, eligmodo ... | 2015 | 27035350 |
| first record of mastophorus muris (gmelin, 1790) (nematoda: spiruroidea) from a wild host in south america. | mastophorus muris (gmelin, 1790) (nematoda: spiruroidea) is reported parasitizing the grey leaf-eared mouse graomys griseoflavus (waterhouse, 1837) (rodentia: sigmodontinae) from the province of la pampa, argentina. the distinct position of mastophorus (spirocercidae: mastophorinae) and protospirura (spiruridae), sometimes still confused, is again confirmed. the pattern of pseudolabial teeth (a large central tooth with smaller teeth on each side), which seems to be rather stable in all known des ... | 2003 | 14710636 |
| american tripanosomiasis: a study on the prevalence of trypanosoma cruzi and trypanosoma cruzi-like organisms in wild rodents in san luis province, argentina. | chagas disease is caused by trypanosoma cruzi. wild and perianthropic mammals maintain the infection/transmission cycle, both in their natural habitat and in the peridomestic area. the aim of this paper was to present the results from a study on wild rodents in the central and northern regions of san luis province, argentina, in order to evaluate the prevalence of this infection. | 2010 | 20563490 |