Publications

severely reduced recombination in females of the south american marsupial monodelphis domestica.	the gray short-tailed opossum, monodelphis domestica, is a model species for studying the underlying mechanisms that govern recombination. we have identified a new marker, pi (protease inhibitor), in m. domestica and demonstrate its linkage to ak1 (adenylate kinase 1). the rate of recombination in females of this species is approximately one fifth the rate in males, as might be predicted from the difference in chiasma frequency between the two sexes.	1992	1582262
early differentiation of the gonads in the gray short-tailed opossum (monodelphis domestica).	the time course for gonadal development in gray short-tailed opossums was examined in this study. it was found that the gonads were not differentiated on day 1 of postnatal life (the day of birth). while testis development was seen by postnatal day 4, ovarian development did not occur until after postnatal day 16. in both sexes, primordial germ cells were not identified until after postnatal day 1. these findings are discussed with respect to gonadal differentiation in other marsupial species.	1992	1567932
evidence for high levels of androgen in peripheral plasma during postnatal development in a marsupial: the gray short-tailed opossum (monodelphis domestica).	plasma samples were assayed for androgen in gray short-tailed opossums (monodelphis domestica) on the day of birth and at selected ages through adulthood. levels of androgen in mixed-sex plasma pools of animals 4 and 8 days of age were higher than in either sex at all other ages examined. at postnatal days 16, 30, and 60 (weaning), levels of androgen were equivalent in males and females and as high as in adult males. in both sexes, androgen levels were lower at postnatal day 84 (juveniles) than ...	1992	1547307
restoration of conduction and growth of axons through injured spinal cord of neonatal opossum in culture.	the ability of neurons in the central nervous system to grow through a lesion and restore conduction has been analyzed in a developing spinal cord. the preparation consists of the entire central nervous system of the newly born opossum (monodelphis domestica), isolated and maintained in culture. cell division, cell migration, and reflexes are maintained in such preparations for up to 8 days in culture. in the present experiments, massive lesions were produced by crushing the spinal cord, which a ...	1992	1729714
unexpected oocyte growth after follicular antrum formation in four marsupial species.	during examination of maturing preovulatory marsupial oocytes we noted that oocyte diameters were invariably about 50% greater than the figures reported in earlier histological studies. as all previous investigations were limited to small follicles (at most 25% the size of the ovulating follicle), the present study was initiated to examine oocyte growth during the whole period of follicular development. oocyte and follicle diameters were measured for three australian (trichosurus vulpecula, macr ...	1992	1339855
evidence from plasma progesterone concentrations for male-induced ovulation in the brush-tailed bettong, bettongia penicillata.	female brush-tailed bettongs, bettongia penicillata, were housed with either an intact or vasectomized male or isolated from males in the peripartum period. development of the quiescent corpus luteum formed at the post partum oestrus was initiated by removing the pouch young. blood samples for analysis of plasma progesterone were collected from the females 2 days before removal of pouch young, daily for 5 or 6 days and then 2-3 times each week until 19 days after removal of pouch young. plasma p ...	1992	1625245
purification and characterization of fibroblast growth factors from the opossum, monodelphis domestica, brain.	an extract from the brain of the opossum monodelphis domestica was fractionated by heparin affinity chromatography. a major peak of mitogenic activity (heparin binding growth factor 2, hbgf-2) eluted from heparin-sepharose between 1.7 and 2.0 m nacl. antisera specific for bovine bfgf detected four polypeptides of 17.5-23 kda in opossum brain hbgf-2 preparations. opossum brain heparin binding growth factor 1 (hbgf-1), a minor peak of activity, eluted from heparin-sepharose at 1.1 nacl and contain ...	1992	1380142
antithrombin iii (at3) polymorphism in the marsupial monodelphis domestica: identification and genetics.	antithrombin iii polymorphism was observed in the gray short-tailed opossum, monodelphis domestica, by either one-dimensional polyacrylamide gel electrophoresis (page; ph 7.9), two-dimensional page (agarose, ph 5.4; 12% t, ph 7.9), or isoelectric focusing (ph 4.2-4.9) followed by immunoblotting with rabbit antiserum to human antithrombin iii. family studies demonstrated an inheritance of three codominant autosomal alleles, at3a, at3b, and at3c, and a population study revealed frequencies of 0.70 ...	1992	1296573
evidence that cortical granule formation is a periovulatory event in marsupials.	formation of cortical granules was examined in superovulated oocytes from three marsupial species, brushtail possums (trichosurus vulpecula) tammar wallabies (macropus eugeniii) and grey short-tailed opossums (monodelphis domestica) and in oocytes obtained during natural cycles in macropus eugenii. superovulation was induced by pregnant mares' serum gonadotrophin/gonadotrophin-releasing hormone (pmsg/gnrh) protocols and natural ovulation by removal of pouch young. oocytes were collected after ov ...	1992	1404089
specific chromosomal defects associated with ultraviolet radiation-induced cutaneous tumors in monodelphis domestica (marsupialia, mammalia).	cytogenetic analysis of eight ultraviolet radiation (uvr)-induced cutaneous tumors and one spontaneously transformed fibroblast cell line of monodelphis domestica showed that two of the tumor cell lines were of murine origin and that the remaining six marsupial tumor cell lines had hyperdiploid stemline numbers ranging from 21 to 31. each tumor cell line showed structural and numerical abnormalities. the single transformed fibroblast cell line also showed a hyperdiploid chromosome number with st ...	1992	1486565
the differentiation of the skin and its appendages. i. normal development of papillary ridges.	in the present study, the normal development of papillary ridges was studied in the volar pads of both fore and hindpaws of the opossum, monodelphis domesticus. at birth, the developmental state of the opossum's paws is equivalent to that of a six-week human embryo. the development of papillary ridges in the opossum occurs entirely postnatally and the hindpaw lags behind the forepaw by at least four days in most developmental parameters. papillary ridge formation is preceded by four events: skin ...	1992	1554108
identification of a transforming ras oncogene in an ultraviolet radiation-induced corneal tumor of monodelphis domestica.	chronic exposure of the gray, short-tailed oppossum, monodelphis domestica to ultraviolet radiation (uvr) induces mesenchymal tumors of the cornea. high molecular weight dna samples from 6 uvr-induced corneal tumors were assayed for their ability to transform nih 3t3 cells to tumorigenicity. nih 3t3 cells transfected with dna from 5 of the corneal tumors produced 14 tumors in nude mice. cell lines were established from these tumors. dna from 13 of 14 tumor cell lines contained repetitive opossum ...	1992	1561240
trunk movements during locomotion in the marsupial monodelphis domestica (didelphidae).	the small didelphid cmarsupial, monodelphis domestica, uses a lateral sequence walk during slow treadmill locomotion and gradually shifts to a trot as speed increases. at higher speeds it changes abruptly to a half-bound. cinematographic records suggest significant lateral bending but no sagittal bending of the trunk during the slow walk and a reduced amount of lateral bending during the fast walk. there is slight lteral, but no sagittal, bending during the trot. sagittal bending is obvious duri ...	1992	29865578
uva does not photoreactivate pyrimidine dimers in cultured human fibroblasts.	pyrimidine dimers were induced in duplicates of cultured human skin fibroblasts by irradiation with various doses of uvb radiation. subsequently, one set of cells was further exposed to either 5 or 10 j/cm2 of uva radiation to assess the photoreactivating activity of this spectral range in a human cell system. following irradiation, pyrimidine dimers were quantified in all cells by determining the number of endonuclease-sensitive sites (ess). no difference in the yield of ess was observed betwee ...	1993	8162334
ultrastructural characteristics of in vivo and in vitro fertilization in the grey short-tailed opossum, monodelphis domestica.	to establish the mode of fertilization in a marsupial, a morphological investigation was made of the gametes of the south american grey short-tailed opossum. monodelphis domestica, at the time of fertilization in vivo and in vitro. oestrus was induced in females by the introduction of an unfamiliar male. to obtain oocytes recently fertilized in vivo, females were killed 18-24 hours after the first mating and the region of the oviduct containing eggs excised and fixed. unfertilized mature oocytes ...	1993	8214640
linkage between complement components 6 and 7 and glutamic pyruvate transaminase in the marsupial monodelphis domestica.	the sixth and seventh components of complement were found to be polymorphic and tightly linked in the laboratory opossum (monodelphis domestica), as they are in eutherian mammals. in addition, strong evidence for linkage of the c6-c7 haplotype to the gene for glutamic pyruvate transaminase (gpt) was obtained for females but not for males. this result, combined with previous observations, established as a generality that recombination is severely reduced in females of this species by comparison w ...	1993	8259924
characterization of the k-ras gene of the marsupial monodelphis domestica.	a cdna clone isolated from a plasmid library contains the complete coding sequence for the k-ras gene of the marsupial monodelphis domestica, a south american opossum. the nucleotide sequence of the coding region of the opossum k-ras gene is very similar to the k-ras coding sequences of placental mammals. the coding region of the opossum gene is 95% identical to the human gene at the nucleotide level; the human and opossum genes are 99% identical at the level of encoded amino acids. transcribed ...	1993	8312604
topical toremifene: a new approach for cutaneous melanoma?	the distribution of topically applied toremifene (0.5-1 mg/day for 5 days) in the ultraviolet b (uvb)-induced monodelphis domestica opossum melanoma model was examined. the mean concentration of toremifene measured in the skin was 1200 nmol/g, or > 500 times that detected in any other tissues (blood, brain, liver, testicles, heart, uterus, eyes). in plasma, toremifene could be detected in only one animal of six (0.04 nmol/ml). intraperitoneal administration of 0.5 mg toremifene daily for 5 days ...	1993	8339391
characterization of a marsupial sperm protamine gene and its transcripts from the north american opossum (didelphis marsupialis).	a synthetic oligonucleotide primer, designed from marsupial protamine protein-sequence data [balhorn, r., corzett, m., matrimas, j. a., cummins, j. & faden, b. (1989) analysis of protamines isolated from two marsupials, the ring-tailed wallaby and gray short-tailed opossum, j. cell. biol. 107] was used to amplify, via the polymerase chain reaction, protamine sequences from a north american opossum (didelphis marsupialis) cdna. using the amplified sequences as probes, several protamine cdna clone ...	1993	8344286
why do spermatozoa of american marsupials form pairs? a clue from the analysis of sperm-pairing in the epididymis of the grey short-tailed opossum, monodelphis domestica.	in order to understand the evolutionary significance of sperm-pairing in american marsupials, an ultrastructural investigation was made of this process in the south american grey short-tailed opossum, monodelphis domestica. one epididymis from each animal (5) was fixed for light and electron microscopy and divided into 18 segments. the contralateral tract was divided into similar segments and assessments made of the total number of spermatozoa and the proportion of sperm-pairs. the mean total sp ...	1993	7689796
expression of fibroblast growth factors in ultraviolet radiation-induced corneal tumors and corneal tumor cell lines from monodelphis domestica.	chronic exposure of the gray, short-tailed opossum, monodelphis domestica, to ultraviolet radiation (uvr) induces highly vascularized mesenchymal tumors of the cornea. cell lines derived from these uvr-induced corneal tumors and the corneal tumors themselves were examined for the presence of mrna coding for basic and acidic fibroblast growth factors (fgf), transforming growth factors-beta and -alpha (tgf-beta and tgf-alpha), epidermal growth factor (egf), and tumor necrosis factor-alpha (tnf-alp ...	1993	7683886
the early development of major projections from caudal levels of the spinal cord to the brainstem and cerebellum in the gray short-tailed brazilian opossum, monodelphis domestica.	the brazilian short-tailed opossum, monodelphis domestica, is born 14-15 days after copulation and is available for experimentation at stages of development corresponding to those which occur in utero in placental mammals. in the present study, we took advantage of the opossum's embryology to study the development of projections from caudal levels of the spinal cord to the brainstem and cerebellum using axonal tracing methods. in all cases, a 2-3 day survival time was used for axonal transport. ...	1993	7693371
gestation and placentation in two new world opossums: didelphis virginiana and monodelphis domestica.	estrus, gestation, and placentation were studied in the virginia opossum (didelphis virginiana) and the gray short-tailed oppossum (monodelphis domestica), representatives of the prototypic, new world marsupial family didelphidae. didelphis is a large (3,000 g), pouched opossum that exhibits a 28-day estrous cycle, spontaneous estrus and ovulation, and a high ovulation rate (60 ova per cycle). monodelphis is a small (100 g), pouchless opossum with male-induced estrus and ovulation and a moderate ...	1993	8371092
cranial osteogenesis in monodelphis domestica (didelphidae) and macropus eugenii (macropodidae).	the pattern of onset and general rate of cranial ossification are compared in two marsupials, monodelphis domestica (didelphidae) and macropus eugenii (macropodidae). in both species a similar suite of bones is present at birth, specifically those surrounding the oral cavity and the exoccipital, and in both postnatal events follow a similar course. the facial skeleton matures more rapidly than the neurocranium, which is characterized by an extended period of ossification. most dermal bones begin ...	1993	8445660
the unique stability of the marsupial sperm acrosomal membranes examined by unprotected freeze-thawing and treatment with the detergent triton x-100.	in this study of the unique stability of the marsupial acrosome, experiments were carried out on the acrosomes of spermatozoa of the tammar wallaby (macropus eugenii), common brushtail possum (trichosurus vulpecula) and grey short-tailed opossum (monodelphis domestica). light microscopy showed that 4% of opossum and 15% of possum and wallaby spermatozoa lost their acrosomes after freeze-thawing. electron microscopy revealed that freeze-thawing also induced changes in the acrosomal matrix of some ...	1993	8234885
selected features of marsupial genetics.	as a consequence of the ancient separation of the marsupial and eutherian lineages, comparative genetical studies of these two mammalian taxa can be particularly informative. the potential for marsupial genetical research has been enhanced by the development of laboratory colonies of three 'model' species--macropus eugenii, monodelphis domestica and sminthopsis crassicaudata. in this paper two selected aspects of marsupial genetics are reviewed, one involving cytogenetics and the other linkage. ...	1993	8119591
the development of the long descending propriospinal projections in the opossum, monodelphis domestica.	the origin of the long descending propriospinal (ldp) projections have been studied in adult and developing opossums, monodelphis domestica. this species has been chosen because of the considerable immaturity of the hindlimbs at birth, the postnatal appearance of their motility and the late development of coordination between them and the forelimbs. neuroanatomical tracing has indicated that some ldp projections form postnatally. the ones present at birth arise from the regions of the cord where ...	1993	7683578
gonadal sex differentiation in embryos and neonates of the marsupial, monodelphis domestica: arrest of testis development in postterm embryos.	growth and histological differentiation were studied in 8 litters of embryos and 4 litters of neonate grey short-tailed opossums, monodelphis domestica. the embryonic litters included 2 that had passed their expected birth date, and whose weights exceeded the usual birthweights; we refer to these litters as 'postmature'. there was an abrupt increase in the growth rate of xy gonads after birth, but this was not seen in xx gonads. although there was evidence of testicular differentiation in xy gon ...	1993	8376201
development of connections by axons growing through injured spinal cord of neonatal opossum in culture.	the ability of neurites to grow through a lesion and form synaptic connections has been analyzed in a developing mammalian spinal cord in vitro. after isolation of the entire central nervous system (cns) of the newly born south american opossum (monodelphis domestica) the spinal cord was crushed. outgrowth through and beyond the lesion was observed in living preparations for 2-5 days by staining axons with carbocyanine dyes. the structure of the acute crush and the growing neurites was examined ...	1993	8478604
a high-resolution banding pattern idiogram of monodelphis domestica chromosomes (marsupialia, mammalia).		1993	8485993
the sensory innervation of the periodontium of the third premolar in monodelphis domestica.	location and structure of sensory nerve endings in the periodontium of the third premolar in monodelphis domestica have been investigated by means of light and electron microscopy. the periodontal cleft of the tooth is apically enlarged. the number of nerve endings increases towards apex. three types of sensory nerve endings have been observed: free nerve endings, ruffini nerve endings and lamellated corpuscles. free nerve endings could only be identified by electron microscopy. ruffini nerve en ...	1993	8434506
the sensory innervation of the gingiva and mucosa in monodelphis domestica: an ultrastructural study.	the location and structure of sensory nerve endings was examined in the mucosa and in the gingiva propria adjacent to the third premolar of monodelphis domestica by light and electron microscopy. the mucous membrane of the gingiva propria is covered with a stratified keratinized squamous epithelium. the mucous membrane of the adjacent inner aspect of the lip and of the vestibulum oris were covered with a nonkeratinized squamous epithelium. free nerve endings, merkel nerve endings and lamellated ...	1993	8434505
differential omp expression in opossum accessory olfactory bulb.	using immunohistochemical techniques, olfactory marker protein (omp) was localized to the main (mob) and accessory (aob) olfactory bulbs of 30- and 45-day-old, and adult brazilian opossums, monodelphis domestica. entire olfactory nerve and glomerular layers of the adult opossum mob were darkly stained. in the adult aob the rostral half of these two layers was stained more intensely than the caudal half, and both parts were less darkly stained than the mob. this differential aob staining was not ...	1993	8298073
cell lines derived from ultraviolet radiation-induced benign melanocytic nevi in monodelphis domestica exhibit cytogenetic aneuploidy.	the gray short-tailed opossum, monodelphis domestica, develops dermal melanocytic nevi (mn) after long-term chronic exposure to uvb (midwavelength ultraviolet radiation) alone. we developed cell lines from six uvb-induced dermal benign melanocytic lesion biopsies. one of the mn was determined histologically to be a benign melanoma (bm), whereas the remainder were benign melanocytic hyperplasias (mh). the cell lines were not tumorigenic when injected subcutaneously into athymic nude mice. protein ...	1993	8275453
different rates of axonal degeneration in the crossed and uncrossed retinofugal pathways of monodelphis domestica.	the uncrossed retinofugal fibres in the marsupial monodelphis domestica form a separate bundle as they pass through the optic chiasm. the uncrossed fibres segregate from the crossed fibres a short distance before they reach the chiasm, gathering as an essentially exclusive bundle in the ventral part of the optic nerve. this bundle then passes laterally through the optic chiasm and into the optic tract. the distinctive position of the uncrossed fibres has allowed us to recognise that, surprisingl ...	1993	8270955
sex differences and the role of aromatization in the control of sexually dimorphic behavior and morphology in gray short-tailed opossums (monodelphis domestica).	sex differences in the activating effects of an aromatizable (testosterone, t) and a nonaromatizable (dihydrotestosterone, dht) androgen on sexually dimorphic scent marking and aggressive behavior were examined in gonadectomized gray short-tailed opossums. when compared with males, females showed less chest, head, flank, and hip marking and more fighting behavior in tests with stimulus females and threat behavior in tests with stimulus males following receipt of subcutaneous t, dht, or blank (b) ...	1993	8225259
neural aromatase activity in a marsupial, the gray short-tailed opossum (monodelphis domestica): ontogeny during postnatal development and androgen regulation in adulthood.	neural aromatase activity (aa) was measured in gray short-tailed opossums (monodelphis domestica) on the day of birth and at selected ages through adulthood. in adulthood, regulation by testicular androgens was examined. in mixed-sex samples of whole brain, aa was present at birth and increased until postnatal day (pd) 16. in hypothalamus-preoptic area (hpoa), significantly higher levels of aa were seen in animals on pd 16 than on pd 30 and pd 30 animals had higher levels of aa than all older ag ...	1993	8403383
developmental profile of galanin binding sites in the mammalian brain.	galanin (gal) is a 29-amino acid peptide widely distributed in the mammalian nervous system. recently, gal expression has been shown to increase during periods of neuronal degeneration (e.g., alzheimer's disease) and neuronal injury. our laboratory has previously reported that gal immunoreactivity (gal-ir) is robustly expressed during a time of cns plasticity, development. the striking gal-ir seen during times of cns morphogenesis and neurogenesis led us to the hypothesis that gal may play a rol ...	1993	19912942
lectin histochemical study of early postnatal vascularization of the developing pars distalis adenohypophysis of the gray short-tailed opossum (monodelphis domestica, marsupialia).	individuals from 18 litters between 0.5 day and 13 days post partum, and two adult specimens of monodelphis domestica (marsupialia), were studied by tem and lectin histochemistry. positive reactions for po-lectins in the developing pituitary were found in the vascular and/or perivascular elements; secretory cells did not react. positive vascular reactions varied with both the type of lectin and the age of the developing animal. in the adults, the reactions were reversed: there were no vascular, ...	1993	8363038
gonadal development in the opossum, monodelphis domestica: the rete ovarii does not contribute to the steroidogenic tissues.	the gonads of 273 animals, ranging in age from newborn to adult, were examined in serial histological sections. primordial germ cells were located in the hindgut, dorsal mesentery and gonadal primordia of neonates but were alkaline phosphatase negative. the testis differentiated between d 13 of gestation and birth, about half a day later. testis cords, composed of pre-sertoli cells and containing germ cells, were distributed peripherally in the gonad. ovarian differentiation began on d 6, when a ...	1993	8270475
effects of postnatal exposure to alcohol on reproductive physiology and sexually dimorphic behavior in a marsupial, the gray short-tailed opossum (monodelphis domestica).	the effects of postnatal exposure to alcohol on reproductive physiology and sexually dimorphic behavior and anatomy in adult male and female gray short-tailed opossums were examined. female responsiveness to male pheromones and fertility in both sexes were essentially normal in postnatally alcohol-treated animals. however, aspects of sexually dimorphic behavior were masculinized and defeminized in females and demasculinized in males following gonadectomy in adulthood and treatment with male (tes ...	1993	8214429
differential down-regulation of estrogen receptor-like immunoreactivity by estradiol in the female brazilian opossum brain.	the effects of estrus and prolonged estradiol benzoate (eb) treatment on estrogen receptor-like immunoreactivity (er-li) were studied in the female brazilian opossum (monodelphis domestica) brain. in general, both estrus animals and eb treated animals had reduced er-li in specific brain regions when compared to ovariectomized controls. these results support a down-regulatory role for estrogen in relation to its receptor in the brain, and indicate that er-li is differentially regulated in the mon ...	1993	8374740
novel articular cartilage structure in the south american opossum, monodelphis domestica.	articular cartilage provides smooth surfaces for low-friction, unrestricted movement of opposing skeletal elements. the surface topography of articular cartilage has been the subject of numerous studies and, with few exceptions, is considered to be smooth (at least at the light microscopic level). some studies have reported 'humps' on the articular surface which have been related to underlying chondrocytes residing very close to the surface. here we report on a highly nodular form of articular c ...	1993	8226287
nuzzling in the gray short-tailed opossum. ii: familiarity and individual recognition.	nuzzling is a chemosensory exploratory behavior that enables south american gray short-tailed opossums to dissolved dry conspecific odor deposits in naso-oral secretions and incorporate them into their vomeronasal organs. this report documents that male opossums nuzzle novel (unfamiliar conspecific) male odors significantly longer than familiar (own of familiar conspecific) male odors or clean substrates. such findings suggest that an important ethological function of nuzzling behavior involves ...	1993	8511214
nuzzling in the gray short-tailed opossum. i: delivery of odors to vomeronasal organ.	nuzzling in the gray short-tailed opossum (monodelphis domestica) is exhibited in response to conspecific odor deposits and is involved in chemosensory recognition. nuzzling consists of bouts of repeated forward rubbing motions (with intermittent tapping) with the ventral aspect of the snout over the odor source, while moistening it with naso-oral secretions. the role of nuzzling in odorant d delivery to the vomeronasal organ (vno) was investigated. five opossums were allowed to nuzzle conspecif ...	1993	8511213
ultraviolet radiation-induced corneal tumours in the south american opossum, monodelphis domestica.	chronic exposure of the south american opossum, monodelphis domestica, to ultraviolet radiation (uvr) induced 154 primary tumours of the cornea in 152 eyes. tumours developed gradually; frank neoplasia was preceded by non-neoplastic proliferation of corneal stromal fibroblasts (keratocytes) and extensive neovascularization. histologically, the majority of tumours (134 of 154) appeared to be fibrosarcomas arising from keratocytes, but about 12 per cent of the tumours (18 of 154) had a highly vasc ...	1993	8366202
in vitro fertilization and embryo culture in the grey short-tailed opossum, monodelphis domestica.	in vitro fertilization and early embryo culture was undertaken in the south american marsupial, the grey short-tailed opossum, monodelphis domestica. adult females were induced into oestrus by a system of pairing with an unfamiliar male and mature oocytes were recovered from the ovary 15-18 h after mating and placed in pre-warmed modified mem medium at 33 degrees c (basal body temperature) or 37 degrees c. spermatozoa recovered from the cauda epididymides of adult males were preincubated in medi ...	1993	8345471
cochlear place-frequency map in the marsupial monodelphis domestica.	in order to determine the place-frequency map of the cochlea in the marsupial monodelphis domestica, iontophoretic hrp-injections were made at several locations in the ventral cochlear nucleus. prior to iontophoresis the auditory neurons at these locations were characterized electrophysiologically. the resulting distribution of retrogradely labeled cochlear spiral ganglion cells was analysed by means of a three dimensional reconstruction of the cochlea. the map was established for frequencies be ...	1993	8340271
congestive heart failure in a marsupial (monodelphis domestica).		1994	7898039
respiratory rhythm in the isolated central nervous system of newborn opossum.	1. respiratory activity was recorded from spinal ventral roots in the isolated intact central nervous system (cns) of newborn opossum, monodelphis domestica. these signals occurred in synchrony with movements of the ribs and the electromyogram (emg) recorded from the intercostal muscles during inspiration. rhythmical activity could be recorded for more than 6 h in acute preparations. 2. the rhythm-generating region was shown to be located in the lower brain stem by perfusing different cns region ...	1994	7852902
a new hindiii rflp of nras in the laboratory opossum, monodelphis domestica.		1994	7695130
malignant melanoma in ultraviolet irradiated laboratory opossums: initiation in suckling young, metastasis in adults, and xenograft behavior in nude mice.	litters of suckling young of the laboratory opossum (monodelphis domestica) were irradiated with uv light from sunlamps with a spectral emission peak at 302 nm (uvb) to induce melanocytic nevi. total doses of 0.87-5.0 kj/m2 were divided equally among up to 14 exposures during the 19 days from birth. of 358 sucklings exposed, 217 survived to weaning, and 22 (10%) possessed a nevus when shaved and examined at or after weaning. affected animals were then exposed 3 times/week to 125 j/m2 of uvb for ...	1994	7954432
development of craniofacial musculature in monodelphis domestica (marsupialia, didelphidae).	development of craniofacial muscles of monodelphis domestica (marsupialia, didelphidae) is described. in a period of 4-6 days all craniofacial muscles in m. domestica progress from myoblast condensation, to striated myofibers that are aligned in the direction of adult muscles and possess multiple, lateral nuclei. this process begins 1 to 2 days before birth and continues during the first few days after birth. compared to other aspects of cranial development, muscle development in m. domestica is ...	1994	7799438
[the topography of the pancreas of monodelphis domestica (marsupialia)].	shape and position of the pancreas of monodelphis domestica are described in situ after fixation of the animals with bouin's fluid. the right lobe of the pancreas is the smallest of the three organ parts. the body of the pancreas is placed in a transverse position in the cranial area of the peritoneal cavity. ventral access to it is relatively difficult due to the position of the greater parts of the body dorsal to the stomach. in contrast, the left lobe reaches far caudad. typical for monodelph ...	1994	7956809
microtubule configurations in oocytes, zygotes, and early embryos of a marsupial, monodelphis domestica.	the marsupials represent a separate evolutionary lineage from eutherians from which they diverged over 100 million years ago. in order to explore the origin and mode of centrosome inheritance amongst this group of mammals, this study investigates the microtubule organization during fertilization, parthenogenesis, and polyspermy in the didelphid, monodelphis domestica. microtubules and dna were visualized in maturing ovarian oocytes, parthenogenetically activated oocytes, monospermic and polysper ...	1994	8026625
developmental distribution of gfap and vimentin in the brazilian opossum brain.	cells of glial origin are involved in the morphogenesis of the mammalian central nervous system (cns). characterization of glial-associated proteins during neurogenesis and differentiation may aid in understanding the complexity of cns development. we have utilized immunoblotting and immunohistochemistry to characterize the developmental profiles of glial fibrillary acidic protein (gfap) and vimentin (vim) in the brain of the brazilian opossum, monodelphis domestica. typical of marsupials, cns m ...	1994	8077462
cellular aspects of the development of diarthrodial joints and articular cartilage.	there have been many reports on the histological development of mammalian diarthrodial or synovial joints. while these are useful for comparative purposes, they tell us little of the cellular basis of joint morphogenesis which must underlie a number of morphogenetic defects. the process of joint morphogenesis is complex and can be subdivided into a number of facets and this report will focus on 2 of them. first, the process of joint cavitation in the chick metatarsophalangeal joint, where we pro ...	1994	7928634
spontaneous pituitary adenomas in the brazilian gray short-tailed opossum (monodelphis domestica).		1994	8053134
characterization of cdna encoding basic fibroblast growth factor of the marsupial monodelphis domestica.	we have isolated and characterized a 1,593-bp cdna containing the coding region of the basic fibroblast growth factor (bfgf) gene of a marsupial, the opossum monodelphis domestica. the encoded protein is 156 amino acids long. the bfgf gene of m. domestica is 82-87% identical to the bfgf genes of placental mammals at the nucleotide level and 92-93% identical to these genes at the level of the amino acids encoded. regions of the bfgf molecule important in heparin binding, high-affinity receptor bi ...	1994	8024698
development of spinal cord in the isolated cns of a neonatal mammal (the opossum monodelphis domestica) maintained in longterm culture.	the cns of the newly born opossum removed in its entirety survives and maintains its electrical excitability in suitable culture media for up to ten days at 25 degrees c. the structure of the developing neonatal spinal cord has been studied in the intact animal and in the cultured cns. the differentiation and survival of individual cells and subcellular structures were followed at the light and electron microscopic level. the expression of cell markers in neuronal and glial cells was studied imm ...	1994	8006676
the development of serotonergic projections to the olfactory bulb of monodelphis domestica (the grey, short-tailed opossum).	the offspring of monodelphis domestica (grey, short-tailed opossum) are born in a very immature state after a short (14-day) gestation period. as a result, they provide a useful mammalian model for examining quite early stages of brain maturation. the present study demonstrates that the onset and development of serotonergic (5-ht) projections to the monodelphis olfactory bulb can be traced entirely after birth. 5-ht was visualized in tissue sections from postnatal day 5 (p5), p10, p20, p30, and ...	1994	8174233
blood collection and surgical procedures for the laboratory opossum (monodelphis domestica).	procedures have been developed for collecting blood samples from the laboratory opossum (monodelphis domestica) and for conducting survival surgery on adults. blood samples up to 1 ml were collected routinely by cardiac puncture of animals anesthetized by inhalation of methoxyflurane or halothane with minimal risk; however, halothane required more careful monitoring. surgical procedures such as partial hepatectomy unilateral hysterectomy, and tail wound repair were safely accomplished on animals ...	1994	8007664
susceptibility to ultraviolet-induced corneal sarcomas is highly heritable in a laboratory opossum model.	the laboratory opossum, monodelphis domestica, develops hyperplasia and neoplasia of the corneal stroma after repeated exposure to low doses of ultraviolet radiation (uvr) (non-erythemic in skin). we exposed adult animals from genetically diverse families within our colony to determine whether there are any heritable components to the risk of this form of eye cancer. from about 5 months of age, animals were exposed 3 times a week to a dose of about 125 j/m2 of uvb (spectral peak = 302 nm). thirt ...	1994	8262667
placentation in the dasyurid marsupial, sminthopsis crassicaudata, the fat-tailed dunnart, and notes on placentation of the didelphid, monodelphis domestica.	a light microscope study of the choriovitelline (yolk sac) placenta of the dasyurid marsupial, sminthopsis crassicaudata, and some comparative observations on that of the didelphid, monodelphis domestica, were performed. in the former species, the placenta was composed of an invasive bilaminar, avascular, yolk sac and a non-invasive trilaminar, vascular yolk sac. the bilaminar yolk sac placenta had trophoblast giant cells that eroded the maternal epithelium, but there was no evidence of invasion ...	1994	8182576
the development of sensorimotor reflexes in the brazilian opossum monodelphis domestica.	the development of a number of sensorimotor reflexes was studied in the brazilian opossum monodelphis domestica. at birth, an opossum's forelimbs execute rhythmic, alternate movements which resemble swimming, whereas the hindlimbs are little more than embryonic buds that do not move independent of the trunk. it is possible, therefore, to witness the entire development of hindlimb motility, the advent of coordination between forelimbs and hindlimbs, and the development of ambulation. the followin ...	1994	8038987
timetable of in vivo embryonic development in the grey short-tailed opossum (monodelphis domestica).	the timing of development was examined in 496 embryos from female monodelphis domestica collected at known time intervals after video recorded mating. ovulation occurred approximately 20 hr (day 1) after mating, and fertilization was observed by 24 hr. transport through the oviducts was rapid, and pronuclear stage embryos were recovered from the uterus as early as 24 hr after mating. second cleavage had occurred by 55 hr after mating. three-celled embryos were among those collected on day 3 afte ...	1994	7893485
hearing in primitive mammals: monodelphis domestica and marmosa elegans.	although opossums of the family didelphidae usually serve as a parsimonious starting point for tracing the otological and neurological evolution of modern mammals, audiological data for didelphid opossums is available only for the north american opossum (didelphis virginiana) which because of its large size, may be one of the least representative genera of the family. the present report extends the audiological data to two other species of didelphid opossums, monodelphis domestica, and marmosa e ...	1994	7928716
x-chromosome replication patterns in adult, newborn and prenatal opossums.	somatic cells from the opossums monodelphis domestica and didelphis virginiana were labelled with 5-bromodeoxyuridine (brdu), treated with colchicine, stained with acridine orange and examined using fluorescence microscopy. brdu-incorporated metaphase spreads from females of m. domestica at developmental stages from late bilaminar blastocysts to adults showed replication asynchrony of the two (acrocentric) x chromosomes. the long arm of one x chromosome was the latest replicating region in the e ...	1994	7878226
[prospects for obtaining a mapping panel for somatic cell marsupial-rodent hybrids for the short-tailed opossum monodelphis domestica].	a possibility of obtaining a panel of marsupial-rodent somatic cell hybrid clones has been explored, with a view to mapping the genome of the opossum (monodelphis domestica). fusion of opossum cells (splenocytes, bone marrow cells, and fibroblasts) with fibroblasts of chinese hamster or vole (hgprt- and tk- mutants, respectively) produced 146 hybrid clones. the majority of marsupial-mammalian somatic cell hybrids were characterized by pronounced fragmentation and segregation of marsupial chromos ...	1994	7883155
early development of the optic chiasm in the gray short-tailed opossum, monodelphis domestica.	we have studied the early development of the uncrossed retinofugal projection in the gray short-tailed opossum. axons that form the adult uncrossed retinofugal projection arise from the temporal crescent of the retina and reach the optic chiasm on postnatal day 7. the sites at which the uncrossed fibres segregate from the crossed fibres and the pattern of this segregation are very different from those seen in eutherian mammals. in the opossum, the uncrossed fibres segregate from the crossed fibr ...	1994	7860795
gnrh neurons and other cell populations migrating from the olfactory neuroepithelium.	cell migration from the olfactory neuroepithelium to the brain has been widely studied during vertebrate development. immunocytochemical analysis has revealed that many of the migrating cells contain gnrh (gonadotropin-releasing hormone). the gnrh positive cells migrate from the medial olfactory placode, steam along the nasal septum, cross the basal forebrain and reach the hypothalamic and septal areas from where they control the release of hypophyseal gonadotropic peptides. a peculiar feature o ...	1994	7864581
hprt activity in embryos of a south american opossum monodelphis domestica.	marsupial females show preferential paternal x-inactivation. however, the time at which x-inactivation occurs in early development has not yet been determined. a double microassay which measures the activities of x-linked hypoxanthine phosphoribosyl transferase (hprt) and the autosomally-coded adenine phosphoribosyl transferase (aprt) from the same sample was performed on a collection of embryos from a south american opossum monodelphis domestica. the embryos ranged in age from the 2-cell stage ...	1994	7878225
projection of visuotopically organized afferents to the dorsal thalamus in the opossum, monodelphis domestica.	retrogradely transported dyes, fluorogold and fast blue were injected into both sides of the dorsal thalamus in the monodelphis opossum. projection of the presumed primary visual cortical area, superior colliculus and parabigeminal nucleus to the dorsal lateral geniculate nucleus and the lateral posterior--lateral intermedius nuclear complex were described. they show close similarities to the homologous projections in the north american opossum, insectivores and some rodents. in comparison with ...	1994	7887182
recent advances in cutaneous melanoma oncogenesis research.	the oncogenic transformation of epidermal melanocytes produces primary cutaneous melanoma. in this article, previously published cytogenetic, biochemical, molecular biology, and cell biology studies of cutaneous melanoma oncogenesis are reviewed. a variety of laboratory animal models have been developed for studies of the induction of melanoma, including mice, the laboratory opossum monodelphis domestica, sinclair swine, and xiphophorus fish. some of the advantages and disadvantages of these ani ...	1994	7919546
cloning of a marsupial dna photolyase gene and the lack of related nucleotide sequences in placental mammals.	photoreactivating enzyme, dna photolyase, reduces lethal, mutagenic and carcinogenic effects of ultraviolet light (uv) by catalyzing near uv or visible light-dependent repair of cyclobutane pyrimidine dimers (cpds) in dna. the enzyme activity has been detected in a wide variety of organisms ranging from bacteria to nonplacental mammals. however, the evidence for photoreactivation in placental mammals, including humans, is controversial. as a first step to identify the presence and activity of th ...	1994	7937136
immunocytochemical localization of vacuolar h-atpase in the opossum (monodelphis domestica) kidney: comparison with the rat.	with two different antibodies (a monoclonal antibody to the c terminus of the 31-kd subunit of h-atpase and a polyclonal rabbit antiserum to whole bovine h-atpase) the vacuolar-type h-atpase pump in the different nephron segments of the gray short-tailed (monodelphis domestica) opossum kidney has been immunocytochemically localized. there was moderate staining of the brush border and subvillar invaginations in the proximal convoluted tubules (pct) of the opossum kidney only with the rabbit antis ...	1994	8025229
spatial behavior in the brazilian short-tailed opossum (monodelphis domestica): comparison with the norway rat (rattus norvegicus) in the morris water maze and radial arm maze.	the spatial behavior displayed in a swimming pool and radial arm maze by the brazilian gray, short-tailed opossum (monodelphis domestica) was compared with that of the laboratory rat (rattus norvegicus). the performance of the opossums was clearly different from that of the rats in both tasks. the opossums failed to learn to find a hidden platform in the swimming pool (place task), but they did learn to swim to a visible platform. the opossums did learn working and reference memory components of ...	1994	8026166
igg transport across the gut of the suckling opossum (monodelphis domestica).	we investigated igg transport across the gut of suckling opossums to see whether it is likely to be fc gamma r-mediated. enterocytes isolated from the proximal and distal regions of the small intestine of suckling aged 12-52 days, and reacted with indicator srbc at ph 6.0 or 7.2, bound opossum igg in rosette assays. considerable overall variation was observed in the numbers of enterocytes forming rosettes. no binding was seen with rabbit igg at these ages, or with opossum and rabbit igg when ent ...	1994	8050619
genetic analysis of ultraviolet radiation-induced skin hyperplasia and neoplasia in a laboratory marsupial model (monodelphis domestica).	monodelphis domestica, the laboratory opossum, develops hyperplasia and neoplasia of shaved skin after repeated exposure to ultraviolet radiation (uvr). we exposed monodelphis from genetically diverse families within our colony to determine whether there are any heritable components to the risk of two distinct skin lesion phenotypes-melanocytic nevus (mn) and advanced hyperkeratosis (hk). from about 5 months of age, animals were shaved and exposed three times a week to a dose of about 125 j/m2 o ...	1994	8141607
the critical period for repair of cns of neonatal opossum (monodelphis domestica) in culture: correlation with development of glial cells, myelin and growth-inhibitory molecules.	a comparison was made of neurite growth across spinal cord lesions in the isolated central nervous system (cns) of newborn opossums (monodelphis domestica) at various stages of development. the aim was to define the critical period at which growth after injury ceases to occur, with emphasis on growth-inhibitory proteins, myelin and glial cells. in postnatal opossums 3-6 days old (p3-6), repair was observed 5 days after lesions were made in culture at the cervical level (c7) by crushing with forc ...	1995	8542069
ontogeny of arginine vasopressin-like immunoreactivity in the brazilian opossum brain.	the neuropeptide arginine vasopressin is involved in many centrally mediated functions and brain development. in this study, we have examined the ontogeny of arginine vasopressin-like immunoreactivity (avp-ir) in the brazilian opossum (monodelphis domestica) brain to further understand the involvement of avp in the forming central nervous system. monodelphis is a small pouchless marsupial and its pups are born in an extremely immature state before neurogenesis is completed. in the adult brain, c ...	1995	8575082
humoral immune response in a marsupial monodelphis domestica: anti-isotypic and anti-idiotypic responses detected by species-specific monoclonal anti-immunoglobulin reagents.	we examined the humoral immune response of the laboratory opossum (monodelphis domestica) as a model marsupial species. to evaluate antibody responses, igm and igg preparations were purified from the sera of naïve monodelphis. these two immunoglobulin (ig) preparations were used to generate specific murine monoclonal antibodies for use in elisa-based serology. individual monodelphis were then immunized with a multideterminant protein antigen, a murine monoclonal antibody (mab) igg preparation de ...	1995	8595822
does early monocular enucleation in a marsupial affect the surviving uncrossed retinofugal pathway?	monocular enucleations have been done during early stages (postnatal days 3 to 9) of visual system development of monodelphis domestica, in order to determine whether in this marsupial, as in several eutherian mammals, there are any interactions between the pathways from the two eyes in establishing the uncrossed retinofugal projection. we have examined the distribution and the number of retrogradely labelled ganglion cells that project to the same side of the brain from the surviving eyes short ...	1995	7649832
oligodendrocyte/myelin-immunoreactivity in the developing olfactory system.	immunocytochemistry was used to characterize oligodendrocyte maturation in the developing mammalian olfactory system. postnatal day 10-16, 20, 30 and adult rats were examined, as well as postnatal day 20, 30, 40 and adult monodelphis domestica (the grey, short-tailed opossum). in rats, oligodendrocyte/myelin-immunoreactivity first appears in the accessory olfactory bulb by day 11, with labeling rapidly increasing throughout the entire bulb over the next five days. an adult pattern of immunoreact ...	1995	7675203
uv-induced melanoma. a karyotype with a single translocation is stable after allografting and metastasis.	metastatic melanoma cell lines were derived from a lymph node of a laboratory opossum, monodelphis domestica, which had been exposed to mid-wavelength ultraviolet radiation (uvb) initially as a suckling young, and subsequently as a shaved juvenile and adult. the melanoma cell lines were dendritic and pigmented in vitro and contained a t(6;8)(p13;q13) as the only cytogenetic abnormality. the translocation was detected in 15% of primary cultures (passage 2) from the affected lymph node and in 100% ...	1995	7553587
development and migration of olfactory neurones in the nervous system of the neonatal opossum.	the neonatal opossum (monodelphis domestica) was used to assess how different populations of cells are generated in the olfactory region, and how they migrate along pathways to the central nervous system. developing nerve cells were immunocytochemically labelled using antisera directed against two specific markers of olfactory receptor neurones: olfactory marker protein (omp) and the dipeptide carnosine. in new-born opossums both carnosine and omp are already co-expressed in primary olfactory ne ...	1995	7479995
[the cellular aspects of the development of synovial joints and articular cartilage].	there have been many reports on the histological development of mammalian diarthrodial or synovial joints. while these are useful for comparative purposes, they tell us little of the cellular basis of joint morphogenesis which must underlie a number of morphogenetic defects. the process of joint morphogenesis is complex and can be subdivided into a number of facets and this report will focus on 2 of them. first, the process of joint cavitation in the chick metatarsophalangeal joint, where we pro ...	1995	7478442
ontogeny of oxytocin-like immunoreactivity in the brazilian opossum brain.	the neuropeptide oxytocin (ot) has been shown to function as a neurotransmitter and/or neuromodulator in addition to its hormonal function in the periphery in the adult central nervous system (cns). previously, we have studied the postnatal neurogenesis of the paraventricular and supraoptic nuclei and ontogeny of arginine vasopressin-like immunoreactivity in the brazilian opossum brain, monodelphis domestica. in this study, we have described the ontogeny of oxytocin-like immunoreactivity (ot-ir) ...	1995	8719325
immunohistochemical demonstration of adenohypophyseal hormones during postnatal ontogenesis in the gray short-tailed opossum, monodelphis domestica (marsupialia).	antibodies against human fsh, lh, tsh, acth, gh, prl, and msh were applied to paraffin sections of newborn (< 1) and pouch-young individuals with the age of 1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 13, 14 days, respectively (d1, d2,...). in the pouch-young, the antibody reactions occurred only in the pars distalis of the adenohypophysis. the d < 1 individuals included, the reactions were strong for acth, moderate/strong for gh, and moderate for msh. reactivity for tsh was recorded first in d2 specimens, ...	1995	8835137
evolution of transthyretin in marsupials.	the evolution of the expression and the structure of the gene for transthyretin, a thyroxine-binding plasma protein formerly called prealbumin, was studied in three marsupial species: the south american polyprotodont monodelphis domestica, the australian polyprotodont sminthopsis macroura and the australian diprotodont petaurus breviceps. the transthyretin gene was found to be expressed in the choroid plexus of all three species. in liver it was expressed in p. breviceps and in m. domestica, but ...	1995	7851414
repair and recovery following spinal cord injury in a neonatal marsupial (monodelphis domestica).	1. repair and recovery following spinal cord injury (complete spinal cord crush) has been studied in vitro in neonatal opossum (monodelphis domestica), fetal rat and in vivo in neonatal opossum. 2. crush injury of the cultured spinal cord of isolated entire central nervous system (cns) of neonatal opossum (p4-10) or fetal rats (e15-e16) was followed by profuse growth of fibres and recovery of conduction of impulses through the crush. previous studies of injured immature mammalian spinal cord hav ...	1995	7586707
a critical period for axon regrowth through a lesion in the developing mammalian retina.	although the central nervous system of mature mammals is incapable of regeneration, certain elements present in the developing system must permit and promote the growth of new axons to their initial targets. we investigate whether the environment of a developing visual system is capable of supporting regeneration in the brazilian opossum monodelphis domestica, in which the retinofugal system develops postnatally. retinae were lesioned up to the 16th postnatal day and analysed for regeneration af ...	1995	8542068
perivitelline space of marsupial oocytes: extracellular matrix of the unfertilized oocyte and formation of a cortical granule envelope following the cortical reaction.	the purpose of this study was to characterize the structure of the vestments surrounding unfertilized and cortical granule-reacted oocytes from a marsupial, the grey short-tailed opossum monodelphis domestica and to determine if a cortical granule envelope (cge) forms in the perivitelline space (pvs) following the cortical reaction. unfertilized oocytes collected from mature ovarian follicles and oviducal oocytes that had undergone a cortical reaction were fixed for electron microscopy in the pr ...	1995	8588937
ontogeny of hearing in the marsupial, monodelphis domestica, as revealed by brainstem auditory evoked potentials.	auditory development was studied in the brazilian short-tailed opossum, monodelphis domestica, using the brainstem auditory evoked potential (baep). consistent responses can first be recorded 29 days after birth. the hearing range at the onset of hearing is limited to 5-20 khz with lowest thresholds of 60 db spl at 8-12 khz. during ontogeny, the hearing range expands towards lower and higher frequencies and thresholds decrease until the adult audiogram is obtained by about day 40. peak latencies ...	1995	8647737
myelin-associated neurite growth-inhibitory proteins and suppression of regeneration of immature mammalian spinal cord in culture.	neurite outgrowth across spinal cord lesions in vitro is rapid in preparations isolated from the neonatal opossum monodelphis domestica up to the age of 12 days. at this age oligodendrocytes, myelin, and astrocytes develop and regeneration ceases to occur. the role of myelin-associated neurite growth-inhibitory proteins, which increase in concentration at 10-13 days, was investigated in culture by applying the antibody in-1, which blocks their effects. in the presence of in-1, 22 out of 39 prepa ...	1995	7479918
migrating luteinizing hormone-releasing hormone (lhrh) neurons and processes are associated with a substrate that expresses s100.	luteinizing hormone-releasing hormone (lhrh) containing neurons arise in the region of the medial olfactory placode and migrate into the developing olfactory bulbs and basal forebrain along branches of the terminal and vomeronasal nerves. the neurons ultimately come to reside in olfactory and septo-preoptic areas and project extensively to several brain regions, including the preoptic area and median eminence. the present study examined the expression of a glial-associated guidance molecule, s10 ...	1995	8665661
the effects of neonatal treatment with tamoxifen on sexually dimorphic behavior and morphology in gray short-tailed opossums (monodelphis domestica).	the effects of postnatal exposure to the antiestrogen tamoxifen on sexually dimorphic behavior and morphology in adult male and female gray short-tailed opossums were examined. following gonadecomy and treatment with estradiol in adulthood, neonatally tamoxifen-treated (tx) females showed less female-typical screeching threat behavior and tx males showed less male-typical precopulatory behavior than same-sex controls. while testes failed to descend and phalluses were shorter in juvenile tx males ...	1995	7490006
lectin histochemical identification of carbohydrate moieties in opossum chemosensory systems during development, with special emphasis on vva-identified subdivisions in the accessory olfactory bulb.	lectins, sugar-binding molecules of nonimmune origin, were used in this study to describe the development of the main olfactory and vomeronasal systems in the brazilian gray short-tailed opossum, monodelphis domestica. a battery of seven lectins of the n-acetylgalactosamine/galactose-binding group was used. of the seven lectins, only two, vicia villosa agglutinin (vva) and griffonia (bandeiraea) simplicifolia lectin i-isolectin b4 (gs i-b4), were specific to the vomeronasal system. the other fiv ...	1995	7595957
ontogeny of the skin and the transition from scar-free to scarring phenotype during wound healing in the pouch young of a marsupial, monodelphis domestica.	the marsupial monodelphis domestica provides a versatile model for the study of "fetal" wound healing. the pouch young of this species have been used to perform a systematic histological study of wound healing and skin development throughout pouch life; from pouch day 0 to pouch day 30 with comparisons drawn against adults. we have demonstrated that pouch young heal without macroscopic scars if wounded before pouch day 9 and that a transition into a scarring healing phenotype occurs around the n ...	1995	7750642
neuron-specific enolase as a marker of hypothalamo-neurohypophyseal development in postnatal monodelphis domestica (marsupialia).	in the newborn monodelphis domestica, pituitary and brain are far from their definite shape and structural organization. the presumptive neurohypophysis appears as a mass of proliferating cell immunonegative for neuron-specific enolase (nse) in the newborn, while perikarya positive for nse are present in the rostroventral area of the hypothalamus. at the same time, the periventricular areas of the brain, consisting of proliferating cells, are non-reactive for nse. in the 2.5-day-old specimens of ...	1995	7603626