Publications

correlation of plasma lh and prolactin levels with the fate of the corpus luteum in the vole, microtus agrestis.		1976	775075
pregnancy blocking in the vole, microtus agrestis. ii. ovarian, uterine and vaginal changes.	pregnancy blocking in m. agrestis was associated with a rapid degeneration of cl, growth of follicles, a loss of embryos and return of the uterus to its non-pregnant state, and a return to cornified vaginal smears. these results are discussed in relation to the proposal that the immediate cause of pregnancy block is a failure of prolactin secretion resulting in a failure of cl function.	1976	775074
pregnancy blocking in the vole, microtus agrestis. i. effect of the social environment.	pregnancy failed in a high proportion of newly mated microtus agrestis females when they were exposed to a strange male between 48 and 72 hr after mating with a stud male. this effect of the strange male was testosterone dependent. direct contact with the strange male was normally necessary, and even a single barrier of wire mesh between the female and strange male prevented the male from exerting his pregnancy-blocking effect. the results suggest that the stimuli mediating pregnancy blocking in ...	1976	775073
plasma and pituitary levels of lh in field voles, microtus arvalis, reared under two different photoperiods.	10 plasma lh levels were measured in voles reared under long (15 l: 9 d) or short (10 l: 14 d) light photoperiods by radioimmunoassay from a rat lh-anti ovine lh system. 20 the number of animals exhibiting a detectable lh level (i.e. greater than 1 ng per ml) and the mean plasma lh values were higher for long days than for short days in spite of a very large variability between animals. 30 the sensitivity of the hypophysis towards lh. rh increased after gonadectomy, but is not controlled by the ...	1975	772188
[how the circannual sexual cycle of the malefield vole is determined (author's transl)].	experiments were carried out on male field voles which have been captured in january. the resting sexual state of the animals at this time was determined by examination of the testis and of the genital tract during unilateral castration or by exploratory laparatomy. they were subsequently bred for 30 days in a climatic room, during which time they were fed on winter or spring grass, which has been preserved by freezing. 10 it was observed that a complete return to full sexual activity (from the ...	1975	772187
effects of trypanosoma brucei gambiense infections in microtus montanus on susceptibility to ehrlich's tumors.	trypanosoma brucei gambiense infections in the field vole microtus montanus increased susceptibility to ehrlich's tumor growth. whereas uninfected voles were totally resistant to intraperitoneal ehrlich's ascites tumor cell challenge, over 78% of the animals infected with the trypanosomes developed tumors after challenge. likewise, when ehrlich's ascites cells were injected subcutaneously to induce solid tumor formation, only 7% of uninfected controls developed tumors, whereas over 82% of trypan ...	1976	770326
chromosomes and dna of microtus. ii. confirmation of deletion of constitutive heterochromatin in m. agrestis cells in vitro.	the distribution of constitutive heterochromatin has been examined by c-banding in two somatic cell lines, grown in vitro, from a female microtus agrestis. one line retains one intact x chromosome together with the short arm of the other x chromosome, while the other cell line retains only the short arm of one x chromosome. thus, each cell line has lost substantial amounts of heterochromatin from the sex chromosomes, but this material has been deleted from the cells, and not translocated to othe ...	1977	563281
anatomy of the cecum of the dwarf hamster (phodopus sungorus).	the cecal anatomy of the dwarf hamster, phodopus sungorus, was investigated macroscopically and at the light, transmission electron microscopic and scanning electron microscopic levels. in addition, the arterial supply to the cecum and connecting mesenteries were elucidated. the cecum is divisible into an ampulla ceci and a corpus ceci. in the former, the differentiation of the ileocecal orifice and circumventing fold is described. scanning electron microscopically, the surface topography of the ...	1979	525821
anatomy of the cecum of the vole, microtus agrestis.	the anatomy of the cecum of the vole, microtus agrestis, was investigated using macroscopic dissections, "wet" and dried total specimens, and correlated light, scanning and electron microscopy. the cecum of the vole reveals a series of structural differentiations including a mural lip in the ampulla ceci and a spiral fold in the corpus ceci. the mucosa covering the cecal wall possesses short, wide-opened crypts and differs from the classical descriptions of the large intestinal mucosa. fine stru ...	1979	391099
evidence for a coitally induced 'mnemonic' involved in luteal function in the vole (microtus agrestis).	the development of luteal function in the vole is dependent on a neuroendocrine reflex which is initially activated by mating. bromocriptine was used to destroy the cl initially induced by mating and fresh cl were induced by hormone treatment. the fate of such newly formed cl suggested that the luteotrophic effect of mating continued for about 10 days after mating, despite the destruction of the original mating-induced cl. the luteotrophic effect of mating therefore seems to be 'remembered'. a s ...	1979	390136
pregnancy blockage and the memory of the stud male in the vole (microtus agrestis).	when female voles were allowed contact with the stud male for only 1 h at the time of mating, 55% exhibited pregnancy failure when exposed to a strange male 48 h later. when females were made psuedopregnant by hormone treatment and vaginal stimulation (i.e. no stud male involved), 87% exhibited luteal failure when exposed to a strange male. it is suggested that the characteristics of the stud male are rapidly imprinted upon the female at the time of mating and that this imprinting is important i ...	1979	390135
babesia microti: morphology, distribution and host relationship in germany.	a short review has been given about recent studies on babesia microti in natural animal host's near munich (southern germany). an infected area has been studied in order to elucidate the outdoor relationship between the local strains and their preferred hosts, the european field vole microtus agrestis. the seasonal variation of the parasites prevalence in voles shows a rise in the early summertime (71% of the catches infected). roundish forms predominate in the erythrocytes. multiplication never ...	1979	388948
microtus oeconomus (rodentia), a useful mammal for studying the induction of sex-chromosome nondisjunction and diploid gametes in male germ cells.	preliminary data indicate that chemicals can also increase the frequency of sex-chromosome nondisjunction. positive results--which certainly need further confirmation--have been obtained for mms, p-fluorophenylalanine, vincristine, procarbazine, carbendazim, and bleomycin. nocodazole, benomyl, colcemic, 6-mercaptopurine, and halothane were all negative at the concentrations tested. for the induction of diploid spermatids positive results were only obtained for mms and parafluorophenylalanine. in ...	1979	387396
microtus agrestis and clethrionomys glareolus as experimental hosts of new world leishmania.		1979	386966
repair and survival after uv in quiescent and proliferating microtus agrestis cells: different rates of incision and different dependence on dna precursor supply.	cultured cells of microtus agrestis, the common field vole, perform unscheduled dna synthesis after uv irradiation. they respond to incubation with a dna synthesis inhibitor (1-beta-d-arabinofuranosylcytosine) following uv in ways typical of cells capable of excision repair, with reduced survival and an accumulation of breaks in pre-existing dna. microtus cells irradiated with uv in a quiescent pre-s-phase state are more sensitive to uv than are proliferating cells, in terms of survival. adding ...	1979	379024
testis development in the vole, microtus agrestis, subjected to long or short photoperiods from birth.	voles exposed to long photoperiods (16l:8d) from birth became sexually mature at 40-45 days and remained so up to the end of the experiment at 6 months of age. in short photoperiods development was inhibited up to 60 days but the majority of males became sexually mature between 4 and 6 months of age.	1979	374729
the feedback of exogenous steroids on lh release and ovulation in the intact female vole (microtus agrestis).	female voles were subjected to various regimens of subcutaneous injections of oestradiol-17beta, oestradiol benzoate and/or progesterone. ovulation occurred in only a few of the mature females and in none of the immature animals. there was no indication of any increased lh levels in blood samples taken every 2 h for 50 h after 150 microgram oestradiol-17beta.	1978	364048
[further studies on host range and life cycle of frenkelia microti from the field vole].		1978	358682
[changes in the heterochromatin structure during cell differentiation in uterus epithelium of the field vole].		1977	347764
studies on the control of the corpus luteum in the vole, microtus agrestis.	the lifespan of corpora lutea resulting from hormonally induced ovulations was prolonged by exogenous prolactin, concurrent lactation, or pregnancy. treatment of mated females with bromocriptine resulted in failure of luteal function only when the drug was given before day 6 of pregnancy. pregnancy was dependent on the presence of the ovaries in its later stages. the results suggest that prolactin is luteotrophic in early pregnancy but that a placental luteotrophin may become effective by day 6 ...	1978	344871
enzymic markers of thyroid c cells in some rodents.	the paper provides comparative data of the localization of histochemical reactions demonstrating the activities of alpha-glycerophosphate and succinate dehydrogenases, acid phosphatase, non-specific esterases and non-specific acetylcholinesterase in the c cells of thyroids of 26 animals belonging to 5 rodent species. the family muridae is represented by the wistar albino rat and albino mouse, the family microtidae by the bank vole clethrionomys glareolus (schreber 1780), the field vole microtus ...	1977	340363
free amino acids in brain, liver, and skeletal muscle tissue of voles infected with trypanosoma brucei gambiense.	the concentrations of several acidic and neutral amino acids of brain, liver, and skeletal muscle were determined in field voles, microtus montanus, and compared to values obtained from voles harboring a chronic infection of trypanosoma brucei gambiense. all of the amino acids examined were found at comparable levels in brain tissue from both groups of animals with the exception of tyrosine, which was reduced by approximately 45% in the infected voles. similarly, the only difference noted in liv ...	1977	338875
genetically controlled differences in behaviour between cycling and non-cycling populations of field vole (microtus agrestis).		1977	338556
the isolation and nature of campylobacters (microaerophilic vibrios) from laboratory and wild rodents.	faeces voided by eight species of laboratory or feral rodents were cultured for campylobacters by means of selective methods. campylobacters were isolated from bank voles and from rats, but not from rabbits, laboratory mice, hamsters, guinea-pigs, field mice or field voles. in routine biochemical tests isolates from bank voles resembled a type of campylobacter fetus that causes infectious infertility in cattle; isolates from rats resembled campylobacter coli associated with swine dysentery. elec ...	1977	330861
chromosomes and dna of microtus. iii. heterochromatin rearrangements in m. agrestis bone marrow clones.	newborn microtus agrestis were given single acute whole-body gamma-irradiation (350, 500, or 750r). c-banded bone marrow preparations showed cells with radiation-induced rearrangements of constitutive heterochromatin of the sex chromosomes, usually the consequence of single events, encompassing a wide spectrum of deletions and translocations. these cells persisted in bone marrow for more than a year after irradiation; however, many cells showing the same redistribution of heterochromatin constit ...	1977	328242
methods for determining the proliferation kinetics of cells by means of 5-bromodeoxyuridine.	after treatment of cells with 5-bromodeoxyuridine (budr), the percentage of completely budr-labelled interphase nuclei is greater the longer the budr treatment. the labelling effect is visible after staining with the fluorochrome 33258 hoechst and with giemsa. various formulae and a nomogram are presented by means of which the percentage of cells in s period, duration of the s period and the whole cell cycle can be determined by examination of a single preparation or by comparison of several pre ...	1977	326410
alteration of free serum amino acids in voles infected with trypanosoma brucei gambiense.	free serum amino acid pools of field voles, microtus montanus, were determined over a 24 hr period, and compared to values obtained from voles infected with trypanosoma brucei gambiense. the majority of amino acids in the control animals demonstrated a diurnal variation, peaking predominantly during the dark portion of the photoperiod. this trend was not evident in the infected animals. in addition, infected voles possessed an apparent state of hypoaminoacidemia, with levels of threonine, serine ...	1977	321737
morphological revertants of an avian sarcoma virus-transformed mammalian cell line exhibit tumorigenicity and contain pp60src.	the biological and biochemical properties of rous sarcoma virus-transformed and revertant field vole cells were investigated. revertant vole cells appear morphologically similar to normal, uninfected cells, yet, like transformed vole cells, they are fully capable of growing in agar suspension and producing tumors in athymic nude mice. these highly tumorigenic, yet morphologically normal appearing, vole cells express viral-specific antigens such as the gag gene product (pr76) but lack the env gen ...	1979	226988
nature of rous sarcoma virus-specific rna in transformed and revertant field vole cells.	cytoplasmic and polyribosomal rnas from rous sarcoma virus-transformed and phenotypically reverted field vole cells were fractionated by rate-zonal sedimentation and hybridized with a (3)h-labeled complementary dna viral probe to determine the size classes of virus-specific rna present in these cell types. in contrast to rous sarcoma virus-infected permissive avian cells, only two of three discrete species of virus-specific rna were detected in the cytoplasm of these vole cells. these included g ...	1979	219246
peptide analysis of the transformation-specific antigen from avian sarcoma virus-transformed cells.	sera from rabbits bearing tumors induced by avian sarcoma virus (asv) were ussed to immunopecipitate virus-specific proteins from extracts of chicken, hamster, and field vole cells transformed by asv. two virus-specific proteins having molecular weights of 76,000 and 60,000 were found in all cell lines examined. the 76,000-molecular-weight protein, pr76, is the precursor to the internal core proteins of asv. the 60,000-molecular-weight (60k) transformation-specific antigen from each cell line wa ...	1978	209218
quantitation and localization of rous sarcoma virus-specific rna in transformed and revertant field vole cells.	hybridization analysis of rna from transformed clones of rous sarcoma virus (rsv)-infected field vole cells and revertant subclones indicated the presence of similar amounts of viral-specific rna in both cell types. employing both a relatively uniform and representative complementary dna probe and genomelength complementary dna, we have demonstrated that the majority of rsv proviral dna is transcribed into viral-specific rna in both transformed and revertant clones. the viral-specific rna is pre ...	1978	203719
properties of mammalian cells transformed by temperature-sensitive mutants of avian sarcoma virus.	fibroblasts from european field vole (microtus agrestis) and from normal rat kidney (nrk) have been infected by avian sarcoma virus mutants which are temperature-sensitive for the maintenance of transformation. these cells are transformed at 33 degrees c, but show normal cell characteristics in morphology, colony formation in agar, saturation density, sugar uptake and membrane proteins at 39 degrees c and 40 degrees c, the nonpermissive temperatures. ts mutant virus was rescued from most of the ...	1977	195741
pathomorphologic findings in short-tailed voles (microtus agrestis) experimentally-infected with frenkelia microti.	following oral infection of microtus agrestis with sporocysts of frenkelia microti, transient focal necrosis and cellular infiltrations in the liver, hyperplasia of lymphoid organs, and inflammatory infiltrations in the heart, pulmonary veins, skeletal muscles and brain occurred during the first asexual multiplication period of the parasite in the liver. frenkelia cysts were first observed in the brain 23 days after infection.	1979	113563
labelling of dna and differential sister chromatid staining after brdu treatment in vivo.	a method of labelling dna in vivo with 5-bromodeoxyuridine (brdu) is described. after 6 h permanent subcutaneous infusion of brdu in rodents (adult microtus agrestis, pregnant nmri-mice), cell nuclei which have undergone dna synthesis during the brdu treatment can be differentiated from the nuclei of other cycle stages by means of their altered staining behaviour after giemsa. 24 h after the brdu treatment, mitoses from both bone marrow of the adult animals and tissues from the fetuses showed a ...	1976	60205
late dna replicaion of x chromosomes in female and pseudofemale cells of microtus agrestis.	the late replication pattern of the short arms of the x chromosomes of microtus agrestis was studied in female cells and in cells with 2 x chromosomes of male origin by means of the budr-giemsa technique and of 3h-thymidine labelling. the light absorption of giemsa stained chromosome sections which were unifilarly substituted with budr (labelled), was found to be 59.2% of that of unlabelled chromosomes. in female cells, asynchrony of dna replication of both x chromosomes indicated the presence o ...	1975	53180
visualization of nucleolar organizer regions im mammalian chromosomes using silver staining.	a simple ammoniacal silver staining procedure, designated ag-as, differentially stains the chromosomal locations of ribosomal dna in certain mammalian species. this was critically demonstrated by ag-as staining of the nucleolus organizer regions in karyotypes of the same species and cell lines used for locating the ribosomal cistrons by dna/rna in situ hybridization. with ag-as, silver stained nors (ag-nors) are visualized as black spherical bodies on yellow-brown chromosome arms. ag-nors were v ...	1975	53131