latent infection and measles meningoencephalitis in syrian hamsters.a strain designated 42-edmonston was isolated from the brain of a syrian hamster 30 days after inoculation during the neonatal period with the reference "wild" measles virus strain edmonston which produced a latent infection accompanied by production of measles antibody and insignificant pathomorphological changes. intracerebral inoculation with the 42-edmonston strain of newborn, one day-and 5-7-day-old syrian hamsters resulted in the development of acute measles encephalitis with typical clini ...197718920
attenuated variants of eastern equine encephalomyelitis virus: pathomorphological, immunofluorescence and virological studies of infection in syrian hamsters.a virulent strain of eastern equine encephalomyelitis virus produced in hamsters a lethal infection with severe lesions of nerve cells predominatly in the anterior parts of the brain. parenchyma necroses occurred in the liver and lymphoid organs. infectious virus and viral antigen were found in all the organs examined with the greatest accumulation in the brain. attenuated variants of the virus produced in most hamsters an inapparent infection. in some animals without clinical signs, focal infla ...197826199
physico-chemical characterization of hamster interferon.the glycoprotein nature of syrian hamster interferon was tested on several immobilized lectins. the specific retention of a small portion (20%) of interferon activity was observed only on concanavalin a-agarose; component i of the interferon (not retained) has an apparent molecular weight of 23,500 whereas component ii (retained) is larger, 31,500. the apparent hydrophobicity of syrian hamster interferon was probed by its chromatography on: (a) straight chain hydrocarbons of varied length; (b) a ...197941232
definition of the major histocompatibility complex equivalent in syrian hamsters. 197825199
concerning the laboratory career of mesocricetus auratus with special reference to transplantation. 197825198
analysis of the major histocompatibility complex in syrian hamsters. ii. linkage studies.the genetic control of the histocompatibility antigens that induce strong alloreactions in syrian hamsters was examined. genetic studies revealed that the alloantigens involved in skin graft rejection, graft-versus-host reactions, and mixed lymphocyte reactions are under dominant single gene control and that these genetic loci are closely linked. these data suggest that this strong histocompatibility locus (i) may represent the major histocompatibility complex equivalent in this species, and thi ...197822948
analysis of the major histocompatibility complex in syrian hamsters. i. skin graft rejection, graft-versus-host reactions, mixed lymphocyte reactions, and immune response genes in inbred strains.five inbred strains of syrian hamsters (mesocricetus auratus) were examined for the presence of disparity at a genetic region similar to the major histocompatibility complex in other species. vigorous reciprocal alloreactions developed in several strain combinations, which resulted in acute skin graft rejection, strong mixed lymphocyte reactions, and potent graft-versus-host reactions. in addition, we found evidence for an immune response gene which controls the antibody response to bovine serum ...197822947
an in vivo and in vitro analysis of the alloantigen response in syrian hamsters. 197722946
role of salivary ribonuclease in pathogenesis of patients with periodontal disease a distinct increase in secretion of salivary acidic and alkaline rnaases was found. the rnaases activity in mixed saliva correlated with the intensity of degradation of periodontal tissues during loss of alveolar layer in aged wistar rats and the spontaneous periodontal disease in cats. in experiments with golden hamsters salivary rnaase was found to penetrate through mucosa in active form. the purified salivary rnaase inhibited the protein biosynthesis in ra ...197617223
stable mutants of mammalian cells that overproduce the first three enzymes of pyrimidine nucleotide biosynthesis.upon exposure to 0.1 mm n-phosphonacetyl-l-aspartate (pala), a transition state analog inhibitor of aspartate transcarbamylase, most cells of a simian virus 40 (sv40)-transformed syrian hamster line are killed within a few days, but resistant mutants form spontaneously with frequency 2-5 x 10(-5) in a stochastic process not dependent upon the presence of the inhibitor. the resistant phenotype is stable for many months in the absence of pala. other cell lines also give resistant mutants, but with ...197612870
enzymatic synthesis of biopterin from d-erythrodihydroneopterin triphosphate by extracts of kidneys from syrian golden enzyme system was found in either crude homogenates of dialyzed extracts of liver, kidney, lung, and brain from syrian golden hamsters that catalyzed the synthesis of radioactive 6(l-erythro-1',2'-dihydroxypropyl)pterin (biopterin) from u-14c6(d-erythro-1',2',3'-trihydroxypropyl)-7,8-dihydropterin triphosphate (d-erythrolh2neopterin-ppp) preparation. the specific radioactivity of biopterin was found to be comparable to that of d-erythroh2neopterin-ppp. the enzyme system from hamster kidney wa ...197610299
tissue catecholamine levels of the golden hamster (mesocricetus auratus) acclimated to 7, 22 and 34 degrees c. 19753371
detection and localization of specific antigens in the reproductive tracts of cycling, pregnant, and ovariectomized hamsters.a systematic search was made for components specific to the female reproductive tract in golden hamsters. antisera produced in rabbits against saline homogenates of hamster uteri (collected on the night of estrus) cross-reacted extensively with extracts of 12 other tissues in agar gel double-diffusion assays. absorption of the antisera with small intestine, lung, and liver rendered the immune sera specific for uterine and oviductal antigens (within the limits of the sensitivity of the precipitin ...197548484
properties of prostatic cultures transformed by hamster prostatic tissue has been previously evaluated as a model for human prostatic carcinoma. because the original cell line was lost, syrian golden hamster prostatic tissue has been established in explant culture and infected with a 10-6-cell tissue culture infectious dose (50 percent effective) of sv40. after in vitro transformation, the cells were produced in quantity and 60 times 10-6 cells were injected into adult male syrian golden hamsters 24 hours after 400 rads of w ...197548416
cellular proliferation and renewal in the various zones of the hamster epididymis after colchicine administration.cellular proliferation was examined in the various regions of the excurrent ducts of the reproductive system of the male golden hamster after colchicine administration. each of the two zones of the ductuli efferentes displayed only infrequent mitotic figures. similarly, the basal cell population of the epididymis as well as the epithelium of the vas deferens exhibited too few mitotic figures to allow meaningful evaluation of cellular proliferation. the following observations were reported. 1. th ...197547817
argyrophilic carcinoids in two syrian hamsters (mesocricetus auratus).argyrophilic carcinoids were found in 2 syrian hamsters (mesocricetus auratus). a solitary neoplasm was located in the glandular stomach of a 25.5-month-old animal that had ingested for 12 months laboratory chow to which arecoline and calcium hydroxide [ca(oh)2] had been added. in the other hamster, a primary carcinoid of the pancreas had metastasized to the mesenteric lymph nodes and liver; this was in a 22-month-old animal that had ingested for 16 months chow containing added snuff and ca(oh)i ...197546277
improvement of pancreatic cancer model by modified treatment with n-nitroso-bis (2-oxopropyl) amine.comparative studies were conducted in 2 groups of syrian golden hamsters treated with n-nitroso-bis (2-oxopropyl)amine (bop) weekly for life (group a) or weekly for 6 weeks (group b), and sacrificed at 2-week intervals. pancreatic neoplasms developed as early as 8 weeks (group b) and 10 weeks (group a); however, in group b there were fewer, smaller lesions, well-differentiated morphologically. liver neoplasms occurred only in group a, while gallbladder and kidney tumors were seen in both groups. ...197745725
[interferon induced in the hamster by subunits of "nocardia": essay of protection against rabies (author's transl)].lipid-free cells of nocardia opaca and a cell extract (nwsm) are interferon inducers in syrian hamsters: peak interferon appears 2 h after injection as compared to 8 h in the case of interferon induced by inactivated ndv virus. the interferon induced by nocardia product is inactivated by a treatment for 30 min at 56 degrees c or 24 h at ph 2: ndv-induced interferon is more stable under these conditions. hamsters inoculated with nwsm before and after infection with rabies virus are partially prot ...197943690
interspecies interactions of arboviruses. iii. competition for virus envelope antigens in mixed getah and sindbis virus populations.interactions of getah and sindbis virus populations in mixed infections of 5 tissue systems were competitive or neutral. the type of interaction is regulated by the host cell and virus population density. on reproduction in mouse brains and spev cell cultures the mixed population exhibited antigenic markers of getah virus; in syrian hamster kidney and chick embryo cell cultures those of sindbis virus; and in chinese hamster kidney cell cultures the antigenic markers of both viruses. mixed popula ...197829465
hemolytic assay of complement and its components from syrian hamster (mesocricetus auratus) and mongolian gerbil (mariones unguiculatus).syrian hamster sera may be assayed for hemolytic complement (c) activity by standard procedures with sensitized sheep erythrocytes as used for human sera, but mongolian gerbil sera had higher complement titers when tested with sensitized guinea pig erythrocytes as target cells. the optimal conditions for in vitro testing of hamster c were ph 7.3, ionic strength 0.15, and presence of 1 micrometer of mg2+ and 0.3 micrometer ca2+. for gerbil c the optimum ph was 8, ionic strength 0.074, and the sam ...197828965
[localization of specific antigen in the organs of animals inoculated with different series of live measles vaccine].specific antigen was identified by the immunofluorescent test in the walls of the brain blood vessels, in the neurons, and in the glial cells of albino newborn mice and syrian hamsters inoculated subcutaneously with 4 different batches of live measles vaccine. the pathomorphological test of the brain tissue revealed mainly vascular disturbances. the data obtained testify to the presence of residual neurotropism in the attenuated measles virus (strain "l-16").197877691
the action of chrysaora quinquecirrha (sea nettle) toxin in inhibiting the intestinal transport of glucose in the golden hamster. 19767861
monoamines, estrogen and female sexual behavior in the golden the golden hamster drugs which inhibit monoaminergic function (including p-chlorophenylalanine (pcpa), methysergide and a-methyl-p-tyrosine (a-mpt) facilitated lordosis in ovariectomized female hamsters as a function of the duration of estradiol benzoate (eb) priming. a-mpt (200 mg/kg), methysergide (6 mg/animal) or pcpa (150 or 360 mg/kg) potentiated lordosis if 6 days of eb priming preceded drug treatment. however, if female hamsters were primed with eb for only 2 days, a-mpt and methysergi ...197825118
block of hamster fertilization by anti-ovary antibody.antibody produced in rabbits against hamster ovary blocked fertilization of golden hamster eggs in vitro by binding to the surface of the zona pellucida and rendering it impenetrable to spermatozoa. the antibody was also effective in blocking fertilization in vivo. an intraperitoneal injection of the antibody into females resulted in the complete inhibition of fertilization for approximately 12 days, i.e. three oestrous cycles. this temporary sterility was apparently due to the binding of the an ...197554424
viral expression, oncogenicity, and antigenicity of a mouse salivary gland tumor and two cell lines derived from in vitro cell line (sgt) derived from a mouse submaxillary gland adenocarcinoma (tgs) containing a and b viral particles maintained its oncogenicity only for newborn isogeneic hosts (c3h/he mice) immunosuppressed with antithymocyte serum. inoculation into adult isogeneic animals did not cause tumor but provided partial protection against a challenge with tgs cells. the loss of oncogenicity for nonimmunosuppressed isogeneic hosts was accompanied by the acqusition of oncogenicity for adult, non ...197550130
streptozotocin and renal amyloidosis in the syrian the syrian hamster, administration of the drug streptozotocin was associated with an increased incidence and severity of renal amyloidosis. some of the more severely affected animals showed a frankly nephrotic picture. although some of the diseased animals showed decreased levels of serum albumin, no other definite changes in serum proteins were noted, nor was there any evidence of glomerular immunoglobulin or immune complex deposition. none of the lesions previously found after administratio ...197659551
a possible change in the rate-limiting step for cardiac norepinephrine synthesis in the cardiomyopathic syrian hamster.the development of heart failure in the cardiomyopathic hamster is associated with a decrease in norepinephrine stores and parallel increases in cardiac sympathetic tone and tyrosine hydroxylase activity. despite the increase in tyrosine hydroxylase, cardiac norepinephrine synthesis does not increase in heart failure. in this study, we have shown that an accumulation of cardiac dopamine accompanies the decline of cardiac norepinephrine. the abnormal content of norepinephrine and of dopamine in t ...197721758
sequential morphologic alterations in the bronchial epithelium of syrian golden hamsters during n-nitrosomorpholine-induced pulmonary tumorigenesis.n-nitrosomorpholine (nm)-induced pulmonary carcinogenesis was examined by light and electron microscopy in a 20-week serial sacrifice study using syrian golden hamsters. first to be observed were a proliferation of endocrine apud cells and a formation of lamellated inclusion bodies in the cytoplasm of clara cells. after continued nm treatment, apud cells underwent squamous metaplasia and clara cells invaded the pulmonary tissues adjacent to the bronchi. lung tumors consisted of cells possessing ...197720781
effect of candicidin and colestipol on the testes and prostate glands of bio 87.20 hamsters.the oral treatment of groups of aged bio 87.20 male hamsters, an inbred line of syrian hamsters that develops spontaneous cystic prostatic hypertrophy, with either the heptaene macrolide, candicidin, or the bile acid-sequestering anion exchange resin, colestipol, resulted in a significant reduction of prostate size and weight. the effect was most prominent in the high dosage (75 mg per kg per day) candicidin group and moderate in the high dosage (400 mg per kg per day) colestipol group. it was o ...197660302
tyrosine hydroxylase activity in the heart of the cardiomyopathic syrian hamster. 197717012
[correlation of in vitro testing and therapeutical results in animal transplanted tumors after cytostatic treatment].the antineoplastic activity of 5 substances was tested in vivo and in vitro on four different tumours (plasmocytoma and melanoma fortner iii of the syrian golden hamster, the walker carcinosarkoma 256 and an adenocarcinoma of the rat). the substances involved were 2,3,5-triethyleniminobenzoquinone-(1,4) (triaziquone), actinomycin d, podophyllinic ethylhydrazide (mitopodozide), bleomycin and adriamycin hydrochloride. the effect of the substances in vivo was measured on the size of the tumour, and ...197550072
glycolipid glycosyl transferases of a hamster cell line in culture. i. kinetic constants, substrate and donor nucleotide sugar specificities.the properties of enzymes catalysing the transfer of a galactose from udp-galactose to exogenous ceramide monohexoside and ceramide di-hexoside derived from the syrian hamster cell line nil 2 were studied. the products of these enzymes were characterized by chemical and enzymatic methods. kinetic analyses showed that the enzymes are susceptible to inhibition and activation by a number of substrate analogues. the kinetic and inhibition constants, glycolipid substrate specificity and nucleotide su ...19764123
transmission of creutzfeldt-jakob disease to syrian hamster. 197765576
investigations on the carcinogenic burden by air pollution in man. xiv. effects of automobile exhaust condensate on the syrian golden hamster lung.syrian golden hamsters were intratracheally instilled with 5 or 2.5 mg/animal of automobile exhaust condensate at two weekly intervals. moribund animals were fixed by intravascular perfusion. samples of lobar and segmental bronchi, as well as of peripheral lung tissue, were taken for electron microscopical examination. in addition, all organs were examined histologically. after a survival time of 30 to 60 weeks all animals developed multiple pulmonary adenomas, thus indicating a marked carcinoge ...197665878
studies on sex chromosomes of four hamster species: cricetus cricetus, cricetulus griseus, mesocricetus auratus, and phodopus this paper, we present an analysis of the sex chromosomes of four hamster species after application of different staining techniques. the mitotic x chromosomes show a striking similarity in g-banding pattern but rather great differences in their c-banding patterns. a presumably homologous euchromatic segment that exhibits two distinct g-bands appears in the x chromosome of each species. the y chromosome of cricetus cricetus is in contrast to those of the other species, because it reveals a re ...197767011
major histocompatibility complex in syrian hamsters: are sd determinants present? 197768589
pulmonary tumorigenesis in syrian golden hamsters after intratracheal instillations with automobile exhaust condensate.syrian golden hamsters were intratracheally instilled once every two weeks for life with automobile exhaust condensate (aec) at two dose levels. the condensate was prepared from the most common german passenger car driven in the europa-test cycle (simulated city driving) and contained 340 microgram/g benzo(a)pyrene (b(a)p). despite the very low total dose of b(a)p received, all animals of both dosage groups developed multiple pulmonary adenomas. electron microscopy revealed these tumors to resem ...197769482
lack of expression of type c hamster virus after neoplastic transformation of hamster embryo fibroblasts by benzo(a)pyrene.syrian hamster embryo fibroblasts transformed in vitro with benzo(a)pyrene were analyzed for the presence of type c viral components, including extra- and intracellular reverse transcriptase activity, intracellular type c hamster virus-related rna, and cellular hamster virus group-specific antigen. no evidence could be obtained for the presence of any of these components, although they were easily detectable in hamster fibroblasts producing either b-34 virus (a hamster virus pseudotype of harvey ...197771196
sv40 tumor rejection induced by vesicular stomatitis virus bearing sv40 tumor-specific transplantation antigen (sv40-tsta). ii. association of sv40-tsta activity with liposomes containing vsv glycolipids.highly purified vesicular stomatitis virus (vsv) was obtained from vsv-infected sv40-transformed and from "normal" hamster cell lines. a glycolipid extract was prepared from these vsv preparations according to the folch partition procedure. these glycolipids were rendered immunogenic to the syrian hamsters when incorporated within liposomal membranes composed of lecithin/sphingomyelin/cholesterol (1/1/2 by weight). when the glycolipids were extracted from vsv grown on cell lines (tsv5-cl2 and eh ...197771275
[in vitro and in vivo activity of tiamulin against leptospires (author's transl)].the minimal growth inhibiting concentration of tiamulin, a derivative of the diterpen antibiotic pleuromutilin, was evaluated in vitro against 11 different serogroups of leptospira interrogans by twofold serial dilution technique, in comparison to tetracyclin, dihydrostreptomycin and tylosin. the range of the mic values of tiamulin is between 0.07 and 2.5 microgram/ml and thus comparable to the activities of the standard antibiotics tested (see table 1). the chemotherapeutic efficacy (ed50) of t ...197774926
[study of human diploid cell strains for the presence of oncornavirus determinants].the wi-38 strain of human diploid cells (hdc) and two strains, l-58 and l-63 isolated in moscow research institute of virus preparations were examined in the course of sequential passages for the presence of primate oncornaviruses and their antigens. in parallel, the tumorigenic capacity of the cells was tested by inoculating them into the cheek pouch tissue of syrian hamsters. in all cases the examined hdc cultures contained no oncornavirus particles or their antigens and in no case showed any ...197878588
a gene (bevi) on human chromosome 6 is an integration site for baboon type c dna provirus in human cells.human va-2 cells infected with baboon type c virus were cloned and fused to syrian hamster cells, and 33 primary hybrid colonies were obtained. these cells segregated human chromosomes and retained the complete hamster genome. assays for type c viral p30 antigen and reverse transcriptase were performed in conjunction with analyses of 30 gene-enzyme systems representing 22 different human chromosomes. the results comfirmed that a gene, bevi, previously assigned to human chromosome 6, dominantly c ...197880284
metal chelate affinity chromatography of hamster interferon.syrian hamster interferon, produced by benzo(a)pyrene-transformed embryo cells does not display an affinity for zn++ chelate-agarose. however, the interferon binds to cu++ chelate-agarose and can be displaced from the column by a falling ph-gradient. the chromatography of crude hamster interferon preparation on a tandem of columsn: zn++ chelate-agarose in equilibrium cu++ chelate-agarose results in a 25-fold purification of interferon.197830433
selective decontamination of the digestive tract of syrian hamsters.conventional syrian hamsters colonized with aerobic gram-negative bacteria such as pasteurella pneumotropica and various enterobacteriaceae species were successfully and permanently freed from these microorganisms by oral treatment for 4 weeks with dihydrostreptomycin and 'orabase' premixed with appropriate antibiotics. concomitant oral treatment with dimetridazol for the elimination of intestinal flagellates was unsuccessful. during treatment the animals were maintained under germ-free isolatio ...197882636
blood gas analyses of hibernating hamsters and dormice.blood gases were measured in hibernating and hypothermic animals as a biological model of clinical hypothermia. blood gas analyses from hamsters and dormice were carried out with the aid of permanent arterial catheters during normothermia and hibernation. in golden hamster ph increased from 7.30 to 7.46 during hibernation and paco2 decreased from 59.7 to 40.5 mm hg. in dormice ph increased from 7.24 to 7.44 and paco2 decreases from 38.5 to 27.4 mm hg. the actual bicarbonate concentration increas ...197611444
attempts to reproduce amyotrophic lateral sclerosis in laboratory animals by inoculation of schu virus isolated from a patient with apparent amyotrophic lateral sclerosis.a virus isolated from the csf of a patient who had amyotrophic lateral sclerosis for 7 years, and prolonged pleocytosis in the csf, was adapted to suckling mouse brain by subsequent serial blind passages. this schu virus belongs to the tick-borne encephalitis complex of the genus flavivirus (togaviridae). suckling mouse brain homogenate of the 13th passage was used for transmission experiments in various species of laboratory animals. golden hamsters infected subcutaneously fell ill after a numb ...197984063
heterogeneity of constitutive heterochromatin in somatic syrian hamster chromosomes.syrian hamster constitutive heterochromatin was analyzed for c-band distribution and for bru late-replication pattern. characteristic for this species is relatively large amounts of sex-chromosome and autosomal heterochromatin. the distribution of constitutive heterochromatin was determined. the long term of the x chromosome, the whole y, the short arms of 8 autosomal pairs, the long arm of the smallest metacentric pair, and the centromeric regions of 12 pairs stained intensely dark on c-band pr ...197988308
sensitivity of tsta and species-specific cell membrane antigens of tumor cells to glutaraldehyde vivo immunogenicity and in vitro species-specific membrane antigens in tumor cells treated or untreated with glutaraldehyde (ga) were studied. two different syngeneic syrian hamster transplantable tumor cell lines (spontaneous liver cancer and sv40-induced sarcoma) not only lost immunogenicity after ga treatment but were responsible for enhancement of test-tumor growth in immunized animals. in vitro mixed hemadsorption test used for determination of species-specific membrane antigens in syria ...197898720
studies of estrogen induced renal tumours in male syrian hamsters. i. cytochemical studies of lysosomal enzymes acid phosphatase and beta-glucuronidase.the localization and concentration of lysosomal enzymes acid phosphatase and beta-glucuronidase in kidney cells of syrian hamsters after des administration were studied. a positive cytoplasmic reaction was demonstrated for both enzymes. increased activity of these enzymes were observed in renal tumour in contrast to normal homologous cells. these results can be explained on the basis that lysosomal enzymes were synthesized in tumour cells at a higher rate or it may be due to the invasion of tumo ...197899953
[morphological studies on cellfree induced sarcomas in syrian hamster (author's transl)].morphological studies on sarcomas induced in syrian hamsters by cellfree transmission are described. the tumour tissue for the cellfree preparations stemmed from a sarcoma, containing c-particles. basically, three histological groups have been distinguished: 1. neoplasms of the peripheral nerve-sheath, 2. undifferentiated sarcomas, and 3. liposarcomas. furthermore, a rhabdomyosarcoma, an angiosarcoma and, in a heterotransfection on rat, an osteosarcoma have been established. the great majority o ...197660983
interspecies interactions of arboviruses. i. competition phenomenon in mixed populations of japanese encephalitis and west nile viruses.two phenomena, competition and independent reproduction, were observed on co-cultivation of japanese encephalitis (je) and west nile (wn) viruses in permissive systems. competition occurred in populations propagated in mouse brains and led to elimination of je virus. only clones of wn virus were isolated from these populations at the 1st-3rd passage level. no competition was observed in mixed infection of primary syrian hamster kidney (shk) cell culturess the population had the combined immunolo ...197661719
[vascularization of malignant melanoma in golden hamster]. 197994247
further characterization of csap, an antigen associated with gastrointestinal and ovarian tumors.colon-specific antigen-p, or csap, was originally extracted from gw-39 tumors, which are human colonic carcinomas serially transplanted in golden hamsters, and antibodies to csap have been produced in the same animal hosts. by means of immunodiffusion and a hemagglutination-inhibition assay, csap has been found to be restricted to adult and fetal small intestine, neoplastic gastric and colonic tissues, inflamed colon, and cystic mucinous tumors of the ovary. csap was shown to be distinct from bl ...197881713
projections to the visual cortex in the golden hamster.retrograde transport of horseradish peroxidase (hrp) was used to determine the origins of afferent connexions to the visual cortex (areas 17, 18a and 18b) in the hamster. the distribution of neurons projecting to the visual cortex from other cortical areas, from the thalamus and from the brainstem was studied using a computer technique for three-dimensional reconstruction. there is a topographically organized projection from the dorsal lateral geniculate nucleus to area 17, but probably to no ot ...1979102666
endogenous androgen concentrations in the dorsal and ventral prostate glands of golden hamsters with benign prostatic tumours [proceedings]. 197883346
[antigenic characteristics of oncovirus persisting in continuous syrian hamster cell culture].the antigenic properties of an oncornavirus persisting in a continuous syrian hamster cell culture (x-100) were studied. by the mutual immunodiffusion test it was shown that virions and virion-producing cells contained a protein antigenically identical to the main structural protein of oncornaviruses type c of syrian hamsters. the materials tested contained no "gs-1" antigens (species-specific antigenic determinants of the main structural protein of mammalian oncornaviruses type c) of murine, fe ...197664023
identification of 7,12-dimethylbenz[a]anthracene metabolites that lead to mutagenesis in mammalian cells.the mutagenicity of 7,12-dimethylbenz[a]-anthracene (dmba) and 11 of its enzymatically derived metabolites was tested with chinese hamster v79 cells for identification of mutagenic metabolites. the metabolites consisted of 7-hydroxymethyl-12-methylbenz[a]anthracene, 7-methyl-12-hydroxymethylbenz[a]anthracene, 7,12-dihydroxymethylbenz[a]anthracene, three trans-3,4-diols, two trans-5,6-diols, and three trans-8,9-diols, all of which derived from dmba or from the hydroxymethyl derivatives. mutations ...1979106395
[cattle vaccination against q fever in the rural district of bratislava].cattle attendants on two farms in the outer bratislava district showed symptoms of q-fever. the blood of the cows in these farms was found to contain antibodies to coxiella burnetti and the causative agent of the disease was detected in milk samples of aborting cows by biological assays on hamsters (mesocricetus auratus). the naturally invaded dairy cows with antibodies in the blood and heifers without antibodies were vaccinated with different doses of inactivated suspension of c. burnetii in st ...1978106503
ultrastructural alterations in experimental lingual leukoplakia and carcinoma.epidermoid carcinomas, preceded by dysplastic leukoplakic lesions, were produced on the right lateral borders of the tongues of syrian hamsters by the application, three times per week, of dmba in acetone after the area had been scratched with a root canal broach. animals were killed at 12 to 13 weeks and 15 to 16 weeks. electron microscopic studies of both the dysplastic leukoplakic lesions and the well-differentiated epidermoid carcinomas revealed clumping of tonofilaments and widening of inte ...1979107501
[oncornavirus d associated antigen in cultured human and animal cells].a large number of long-term continuous (ltc) and primarily trypsinized (pt) human and animal cell cultures were examined for the presence of a new oncornavirus d-associated antigen. all the pt cultures were found to be free from this antigen as also human diploid cells and ltc cells of man, rabbit, mouse, dog, swine and bat. ltc cells of monkey, bull, and syrian hamster, however, were found to contain oncornavirus d-associated antigen identical to that previously found in hela, hep-2 and j-96 ce ...1978107657
chemotherapeutically acitve nitro compounds. 4. 5-nitroimidazoles (part iii).more than 100 1-methyl-5-nitroimidazoles substituted in the 2-position via an oxymethyl group were synthesized and their structure-activity relationship toward various protozoa was investigated. among the derivatives substituted with an aromatic radical there are most of the compounds which are highly effective against trichomonads; 9 preparations are superior to tinidazole and 29 are superior to metronidazole in mice infected with trichomonas fetus, and 9 compounds exhibit a better effect than ...1978107955
dna repair in syrian hamster embryo cells treated with 7,12-dimethylbenz[a]anthracene and its weakly carcinogenic 5-fluoro analog.the postreplication repair capacity of syrian hamster embryo cells in culture was determined after treatment with the potent carcinogen 7,12-dimethylbenz[a]anthracene (dmba) and its weakly carcinogenic analog 5-f-dmba. the size and amount of daughter dna sedimenting as high-molecular-weight dna were found to be less in the dmba treated cells than in the 5-f-dmba-treated cells. this difference probably depends upon the types of adducts entering dna replication.1979108012
comparative metabolism and dna binding of 7,12-dimethylbenz[a]anthracene and its weakly carcinogenic 5-fluoro analog.cultured syrian hamster embryo cells readily convert both the carcinogenic polycyclic aromatic hydrocarbon, 7,12-dimethylbenz[a]anthracene (dmba), and its weakly carcinogenic analogue, 5-fluoro-7,12-dimethylbenz[a]anthracene (5f-dmba), to water soluble metabolites. dmba, however, binds to the hamster cell dna at least 2.8-3.0 times more extensively than 5f-dmba. likewise, 5f-dmba is converted to water soluble metabolites by liver microsomal preparations at a rate equal to dmba, but the latter co ...1979108013
induction of tumors in syrian hamsters by a human renal papovavirus, rf strain.injection of rf virus (rfv), a papovavirus isolated from human urine, into newborn syrian hamsters induced subcutaneous sarcomas in 50% of the recipients with 18- to 48-week latent periods. transplantation of 2 x 10(6) primary rfv-induced tumor cells into weaning hamsters caused tumors in 100% of the recipients within 1-2 weeks. continuous tissue culture cell lines were established from two primary tumors; one of these was transplantable. an in vitro-transformed continuous cell line (rf-194) obt ...197663561
alcohol and hamster buccal pouch carcinogenesis.alcohol was shown to enhance the carcinogenic effect of dmba applied to hamster buccal pouch. dmba animals given alcohol developed dysplastic leukoplakic lesions and epidermoid carcinomas 2 weeks ahead of water-drinking control animals. the tumors also grew to larger size, were more invasive, and were more anaplastic histologically. forty young adult syrian hamsters were divided into four groups (alcohol-dmba, dmba control, untreated control, and alcohol control) and were killed after 10, 12, an ...1978104217
low-level x-radiation-induced vascular alterations in normal and dmba-treated, tumor-bearing cheek pouch epithelium of syrian hamsters. 1978104352
life history and histopathology of ultraviolet light-induced skin tumors.the life history and histopathology of uv light-induced skin tumors were studied in nmr rats, outbred female swiss mice, and syrian golden hamsters. high intensity uv light of medium wavelengths produced hyperplasia and papillomas, as well as a dysplastic, intermediary solar keratosis-like stage, with distinct cellular atypia leading to several types of squamous cell carcinomas. high doses of uv irradiation of short duration caused scars, which developed into fibromas and fibrosarcomas composed ...1978112477
encephalitozoonosis in laboratory animals--a serological survey.serum samples of rabbits, guinea pigs, syrian golden hamsters and mice from various breeding stations and laboratory colonies were examined for the presence of antibodies to encephalitozoon cuniculi by the indirect fluorescent antibody test (ifat). of more than 500 rabbits, only those from commercial farms and laboratory colonies were found positive. the number of positive animals fluctuated in different colonies from 0% to 95%. 140 guinea pigs were examined. two colonies were antibody-free, fou ...1979109381
behavioral activities of opioid peptides and morphine sulfate in golden hamsters and rats.the behavioral effects of beta-endorphin, [d-ala2, d-leu5]-enkephalin and morphine were investigated in golden hamsters and in rats. in golden hamsters, beta-endorphin and [d-ala2, d-leu5]-enkephalin induced loss of righting reflex, whereas morphine caused no such effect. both opiate peptides and morphine caused the inhibition of tail-flick response and catalepsy in rats. beta-endorphin was the most potent, followed by [d-ala2, d-leu5]-enkephalin and then by morphine. the catalepsy induced in ra ...1979115044
vascularization of premalignant lesions in carcinogen-treated hamster cheek pouch.of 27 lesions induced in syrian golden hamsters by 12 applications of 0.5% 7,12-dimethylbenz[a]anthracene in liquid paraffin, 14 showed a static phase of at least 28 days' duration in their life history. ten static lesions resumed growth, and this was accompanied by clinically obvious vascularization in 8 cases, 7 of which culminated in carcinomas by the end of the study. because the wall of the normal hamster cheek pouch possesses small nodules whose histologic structure closely resembles that ...1979117196
selective growth of some rodent epithelial cells in a medium containing citrulline.we have defined a medium (called sun's modified waymouth medium) that selectively cultures some rodent epithelial cells that are capable of using citrulline in place of arginine. a growth-response study of the ability of 47 different mammalian cell cultures (of mouse, rat, syrian hamster, chinese hamster, guinea pig, rabbit, monkey, and human origin) to use arginine or its biosynthetic precursors, ornithine, citrulline, or argininosuccinate, showed that all epithelial cells and some fibroblasts ...1979109834
effects of low-level x-radiation on 7,12-dimethylbenz[a]anthracene-induced lingual tumors in syrian golden hamsters.the effects of repeated low-dose-rate, high-dose-rate x-radiation of the head and neck on lingual tumor induction by 7,12-dimethylbenz[a]anthracene (dmba) in syrian golden hamsters were studied. animals received either topical application as 0.5% dmba in acetone on the lateral middle third of the tongue three times a week for 15 consecutive weeks, 20-r x-radiation exposures of the head and neck once a week for 15 consecutive weeks, or concurrent radiation and dmba treatments for 15 consecutive w ...1979109694
[correlation between differentiation and malignancy in human malignant melanocytes "in vivo" and "in vitro" (author's transl)].the relationships between differentiation and malignant transformation were studied in human malignant melanomas in vivo and in vitro. melanocyte differentiation was assessed by ultrastructural morphological characteristis (the appearance of the melanosomes and related structures) localization of dopa-oxidase and assay of 5-s-cysteinyldopa, a specific metabolite. the transformed characteristic of the cells in vitro was evaluated by their ability to give rise to established cell lines, karyologic ...1979114247
the effect of dinitrochlorobenzene (dncb) on dimethylbenzathracene (dmba) carcinogenesis on hamster buccal pouch.dncb is an antigen that stimulates the cell-mediated response in a sensitized host. the purpose of this study was to define the effect dncb would have on a standard model system for oral carcinogenesis, theorizing that tumorgenesis would be delayed or inhibited. fifty-six syrian hamsters were divided into four groups. in group a (dncb/dmba), the right buccal pouch of twenty animals was treated with 2% dncb in orabase, twice a week, and 0.5% dmba, three times a week, for 10 weeks. in group b, twe ...1978101932
effect of sex and season on the production and deposition of lipid and glycid reserves in the intermittently starving golden golden hamster adapted to intermittent starvation (with access to food for 3 days a week only), the glycogen and lipid content of the liver, total body fat and rq values measured in vivo were investigated. these parameters were studied in dependence on the duration of the adaptation period (6 weeks versus 20 weeks), season of the year (winter versus summer) and sex. the liver glycogen content in intermittently starved males and females increases after 6 weeks of adaptation during winter. in s ...1975124886
[mathematical study of estrogen-progesterone antagonisms in the golden hamster].by the test of experimental deciduomata in the golden hamster we have built a curve of hormonal antagonism between estradiol benzoate, and progesterone for growthing doses. the mathematical treatment of this curve allows a comparison with the figure of an enzymatic inhibition reaction.1975126764
specific dynamic action of a high-protein diet and its significance for thermoregulation in the golden a result of the specific dynamic action of a high-protein diet the resting metabolism of golden hamsters within the zone of thermoneutrality is increased on a average by 40%. the specific dynamic action diminishes markedly, with declining environmental temperature. it is concluded from this results that part of the heat produced by the specific dynamic action of a high-protein diet leads to a rise in the lower critical temperature in the zone of thermoneutrality by 2 degrees c.1975127188
[the effect of the argon laser on the vessels, the macro- and microcirculation of the mucosa of the hamster cheek-pouch. an intravitalmicroscopic study (author's transl)].the mucosa of the cheek-pouch of five golden syrian hamsters was irradiated with the beam of an argonionlaser (diameter 0.5 mm and 200 mw). the effect on the micro- and macro-vessels and the bloodstream, especially of the microcirculation, is studied intravitalmicroscopically. in the microcirculation and also in the small and large venous and arterial vessels a restriction of bloodstream, praestasis, pendulumstream, stream reversal and some white microthrombi, -- emboli and agglutination of eryt ...1975129631
effect of different environmental temperatures on the serotonin concentration and turnover in the brain stem of a hibernator.the serotonin (5-ht) and 5-hydroxyindoleacttic acid (5-hiaa) levels and 5-ht turnover were studies in the brain stem of warm- (+30 degrees c) and cold- (+6 degrees c) acclimated golden hamsters, exposed for 3 hours to temperatures of +6 degrees c, +30 degrees c and +37 degrees c, respectively. in war-acclimated hamsters kept under conditions the 5-ht level in the brain did not change significantly during the year. the 5-hiaa level was slightly higher in the winter. the 5-ht turnover varied withi ...1976131333
chemically induced temperature-sensitive mutants of dengue virus type 2: comparison of temperature sensitivity in vitro with infectivity suckling mice, hamsters, and rhesus monkeys.a series of temperature-sensitive (ts) mutants of dengue virus type 2 (den-2, th-36 isolate) were induced by treatment with 5-azacytidine. these mutants and parental viruses were compared for the ts trait and/or attenuation in four systems: primary hamster kidney cells, suckling mice, golden syrian hamsters, and rhesus monkeys. seven clones judged to possess the ts trait in virto demonstrated a variety of patterns in vivo. on initial isolation, five of seven ts mutants exhibited reduced mouse le ...197657925
mutagenicity and metabolism of dimethylnitrosamine and benzo[alpha]pyrene in tissue homogenates from inbred syrian hamsters treated with phenobarbital, 3-methylcholanthrene or polychlorinated biphenyls.there are significant differences between mice and hamsters in polycyclic hydrocarbon and nitrosamine metabolism. homogenates of liver, lung and intestinal mucosa from 6 strains of syrian golden hamster were compared for their ability to metabolize benzo[alpha]pyrene (bp) and dimethylnitrosamine (dmn) to mutagens. females of strains mha/sslak, lsh/sllak, cb/sslak, pd4/lak lhc/lak and lak:lvg (syr) were either untreated or received phenobarbital (pb), 3-methylcholanthrene (mc) or polychlorinated ...1979118380
transplacental effect of nitrosamines in syrian hamsters. iv. metabolites of dipropyl- and dibutylnitrosamine.the present investigations showed that assumed and established metabolites of dipropylnitrosamine and dibutylnitrosamine reach the syrian hamster fetus after subcutaneous (s.c.) treatment of their mothers (at day 14 of gestation). the compounds [2-hydroxypropylpropylnitrosamine, hppn; 2-oxopropylpropylnitrosamine, oppn; methylpropylnitrosamine, mpn; n-nitrosobis(2-hydroxypropyl)amine, bhp; and 4-hydroxybutylbutylnitrosamine, hbbn] were still present in the examined tissue (maternal blood, placen ...1977145753
local and systemic effects of 1-acetoxypropylpropylnitrosamine in syrian golden hamsters.1-acetoxypropylpropylnitrosamine (1-appn) was synthesized and its biological effect examined in syrian hamsters after subcutaneous (s.c.) administration. 1-appn induced mesenchymal and epithelial neoplasms at the injection sites, as well as epithelial tumors in remote organs. local neoplasms were a.c. sarcomas, mammary adenocarcinomas and schwannomas, whereas tumors of the respiratory tract (papillary polyps, papillomas, adenomas, epidermoid carcinomas, and adenocarcinomas) were attributed to a ...1977145754
transplacental effects of nitrosamines in syrian hamsters: i. dibutylnitrosamine and nitrosohexamethyleneimine.the transplacental carcinogenic effects of dibutylnitrosamine (dbn) and nitrosohexamethyleneimine (n-6-mi) were examined in syrian hamsters. a proportion of both substances reached the fetal tissue unaltered. no macroscopic malformations were observed in the offspring; however, postnatal mortality was high. respiratory tumours were found upon histologic examination of surviving animals. single doses of 30 mg/kg body weight (b.w.) dbn and 2 doses of 10 mg/kg b.w. n-6-mi did not induce tumours in ...1976132030
influence of single administration of different diets on the energy metabolism at temperatures of 10,20 and 30 degrees c in the golden hamster.fed animals have a higher resting metabolic rate in the thermoneutral zone than fasting ones. the metabolic increase is due to the specific dynamic action of food. with a decline of environmental temperature this increase in metabolism either declines or remains unchanged; decisive is whether the heat is used for thermoregulation or not (mejsnar and janský 1971). the objective of our work was to find out to what extent a single intake of a diet with a different ratio of nutrients can influence r ...1976133367
carcinogenicity of 1-oxopropylpropylnitrosamine (n-nitroso-n-propyl-proprionamide) in syrian hamsters.the effect of 1-oxopropylpropylnitrosamine (1-oppn) was examined in syrian hamsters. the subcutaneous (s.c.) ld50 was 308 mg/kg b.w. animals treated s.c. once with a high dose of 1-oppn had subcutaneous sarcomas and vaginal papillomas. weekly s.c. injections for life led to high incidences of sarcomas at the injection site. in addition, 1-oppn had a systemic effect. neoplasms developed in the nasal cavity, larynx, trachea, lungs forestomach, and vagina. the results are discussed in connection wi ...1977146323
experimental acetaminophen-induced hepatic necrosis: biochemical and electron microscopic study of cysteamine an attempt to elucidate the biochemical mechanism of acetaminophen-induced hepatic necrosis, the present study in hamsters was undertaken to evaluate the possible changes in lipid peroxidation and microsomal enzyme activities. the protective action of cysteamine was likewise assessed in the light of these biochemical variables and the fine structural features of the liver were seen by electron microscopy. one group of golden syrian hamsters was administered a toxic dosage of acetaminophen (60 ...1978101718
experimental induction of melanotic tumors in syrian golden hamsters by transplacental and topical application of ethylnitrosourea.pregnant syrian golden hamsters were treated with a single intra-peritoneal injection of ethylnitrosourea (enu) solution a few hours pre-parturition. offspring either received no further treatment or from 6 weeks of age, bi-weekly application of enu solution in acetone for 20 consecutive weeks. progeny from non, transplacentally treated mothers were also treated topically. among all treated groups, 8.6% of the animals developed pigmented skin tumors, most of these animals having received the com ...1977146325
testing the trh hypothesis of pineal the syrian hamster gonadal involution may be induced by exposure of the animal to darkness, short photoperiod, or blindness for several weeks. these conditions also influence body metabolism by inducing a substantial decrease in thyroxin concentrations. the role of the pineal gland in these phenomena has been demonstrated by experiments showing that if pinealectomized hamsters are subjected to darkness, short photoperiod, or blindness, their gonads do not involute and plasma thyroxin levels r ...1978101748
[experimental periodontopathies in golden hamster. histochemical studies]. 1976135671
[studies on the effect of chronic cigarette smoke inhalation in syrian golden hamsters and the importance of vitamine a on morphological alterations after smoke exposure (author's transl)]. 1977143143
cytological and cytophotometric studies on dmba--induced changes of the conjunctival epithelium in syrian golden hamsters. 1977143145
electrocardiographic changes in cardiomyopathic syrian hamsters (strain bio 8262).under ether anesthesia electrocardiograms were derived from syrian hamsters (strain bio 8262) suffering from cardiomyopathy and muscular dystrophy. in addition, ventricular weights and body weight were determined. young hamsters -- not yet showing morphological signs of the cardiomyopathy with the exception of possible left ventricular hypertrophy -- demonstrated only a longer ventricular activation time than normal hamsters. with the onset of cardiac necrotization left axis deviation in frontal ...1977143276
transplacental effects of nitrosamines in syrian hamsters. iii. dimethyl- and dipropylnitrosamine.the aliphatic nitrosamines dimethylnitrosamine (dmn), diethylnitrosamine (den), dipropylnitrosamine (dpn), and dibutylnitrosamine (dbn) reached fetal tissue in quantitatively measurable amounts after subcutaneous administration to pregnant syrian hamsters. the compounds were present for at least 2 h in maternal blood, placenta, fetus, and amniotic fluid; dbn was still measurable after 6 h. only a weak or borderline transplacental effect was seen when incidences and latencies of neoplasms in the ...1977145751
a quantitative study of osteoclastic bone resorption during experimental periodontal disease in the golden hamster. 1977143521
antimalarial activity of floxacrine (hoe 991) i. studies on blood schizontocidal action of floxacrine against plasmodium berghei, p. vinckei and p. cynomolgi.floxacrine (hoe 991), 7-chloro-10-hydroxy-3-(4-trifluoromethylphenyl)3,4-dihydroacridine-1,9-(2h, 10h) dion, shows a high level of antimalarial action against blood-induced infection of drug-sensitive and drug-resistant lines of plasmodium berghei in mice, rats and syrian hamsters. the drug is also a potent blood schizontocide against drug-sensitive p. vinckei strains in rodents and p. cynomolgi in rhesus monkeys. the cd50/cd90 values against the drug-sensitive p. berghei strain ascertained in t ...1979120142
androgenic control of the harderian gland in the male golden the golden hamster, there are marked sex differences in the harderian gland. male glands (which are heavier than female glands) possess two cell forms (type i and type ii cells); female glands only exhibit the former. female (but not male) glands contain large amounts of porphyrin, which are readily visible as solid depositions within the lumina. the weight, histology and porphyrin content of the harderian gland was examined in intact adult male hamsters and in male hamsters castrated for 1,2 ...1977144766
[distribution characteristics of leishmania tropica major strains of differing virulence in natural and territorial complexes of the murgab eco-area (southeastern turkmenistan)].in september--october of 1973 and 1974 263 specimens of rhombomys opimus were shot in the territory of the murghab stationar. the seeding of the material (a piece of tissue) from all animals into nnn medium was done. 9 strains of l. tropica major were isolated from this material the virulence of which was studied on 2.5--3 months--old golden hamsters, cricetus auratus. differences in the virulence of the isolated strains according to their natural-territorial complexes are shown. these differenc ...1977145568
spontaneous atrial thrombosis in aged syrian hamsters. i. incidence and pathology.many of the aging syrian hamsters maintained in our division spontaneously develop atrial thrombosis accompanied by a consumption coagulopathy. the 50% mortality level is reached earlier by females (16 months) than by males (24 months). the incidence of thrombosis increases with age, beginning at 13.5 months in females and at 21.5 months in males, and the overall incidence (73%) is nearly the same for both sexes. bilateral ventricular hypertrophy was found in thrombosed hearts. the hearts of mos ...1977145665
transplacental effects of nitrosamines in syrian hamsters. ii. nitrosopiperidine.nitrosopiperidine (np) was found in syrian hamsters quantitatively in the maternal blood for more than 8 h after subcutaneous injection, whereas it disappeared from placenta, fetus and amniotic fluid within the same time period. for n6mi, only traces were seen after 2 h in the same tissues. the long-term transplacental effect of a single dose of np was weak, as demonstrated by a low respiratory tract tumor incidence (p-generation: 54%, f1- generation: 4%). some tumors occurring in the digestive ...1977145750
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