ontogeny of homeothermy in microtus pennsylvanicus and octodon degus. 19751195
immunochemical studies of guinea pig progesterone-binding plasma antiserum specific for guinea pig progesterone-binding plasma protein (pbp) has been prepared. using a very sensitive immunoenzymatic assay, pbp could be detected not only in pregnant guinea pig plasma (970 microgram/ml of plasma at day 40--60 of pregnancy), but also in the plasma of fetuses (2.77 micrograms/ml), umbilical arteries (1.79 micrograms/ml), umbilical vein (2.90 micrograms/ml), and in amniotic fluid (0.47 microgram/ml). the protein was also found in low concentration in the plasma ...197885546
cytomegalic virus-associated insulitis in diabetic octodon degus. 1979224559
diabetic cataracts and flavonoids.oral administration of quercitrin, an inhibitor of aldose reductase, leads to a significant decrease in the accumulation of sorbitol in the lens of diabetic octodon degus. the onset of cataract is effectively delayed when quercitrin is continuously administered. thus in these diabetic animals, as in galactosemic rats, the use of an effective aldose reductase inhibitor impedes the course of cataract development. these observations support the hypothesis that in diabetes, as in galactosemia, aldos ...1977401544
hematologic and serum protein reference values of the octodon degus.blood and serum from normal degus (octodon degus) that ranged in age from 3 to 48 months were analyzed to determine reference hematologic and serum protein values. both sexes were evaluated and were similar. the hematologic and serum protein values for males were: erythrocytes, 8.69 +/- 0.19 x 10(6) /microliter; packed cell volume, 42.1% +/- 0.59%; hemoglobin, 12.0 +/- 0.15 g/dl; leukocytes, 8.50 +/- 0.39 x 10(3)/microliter; neutrophil-to-lymphocyte ration, 40:60; and total protein, 5.70 +/- 0.2 ...1978646210
trichuris bradleyi sp. n., a whipworm from octodon degus in chile. 19751195067
[the helminth fauna of chile: iii. parasites of the degú rodent, octodon degus molina 1782, with descriptions of three new species (author's transl)]. 19751212283
global control in pseudomonas fluorescens mediating antibiotic synthesis and suppression of black root rot of tobacco.pseudomonas fluorescens cha0 colonizes plant roots, produces several secondary metabolites in stationary growth phase, and suppresses a number of plant diseases, including thielaviopsis basicola-induced black root rot of tobacco. we discovered that mutations in a p. fluorescens gene named gaca (for global antibiotic and cyanide control) pleiotropically block the production of the secondary metabolites 2,4-diacetylphloroglucinol (phl), hcn, and pyoluteorin. the gaca mutants of strain cha0 have a ...19921311842
fibre digestion and digesta retention time in guinea-pigs (cavia porcellus), degus (octodon degus) and leaf-eared mice (phyllotis darwini).1. digestibilities of feed and turnover time (1/k), transit time (tt) and mean retention time (mrt: 1/k + tt) of fluid and particle markers were measured in the guinea-pig (cavia porcellus), degu (octodon degus) and leaf-eared mouse (phyllotis darwini) fed a diet containing 50% alfalfa. 2. the digestibility of fibre and the retention time of digesta were highest in the guinea-pig followed by the degu and lowest in the leaf-eared mouse. 3. the difference in the retention time of digesta, resultin ...19921361900
transcription of the bacillus subtilis sacx and sacy genes, encoding regulators of sucrose metabolism, is both inducible by sucrose and controlled by the degs-degu signalling system.the adjacent sacx and sacy genes are involved in sucrose induction of the bacillus subtilis sacb gene by an antitermination mechanism. sacb, encoding the exoenzyme levansucrase, is also subject to regulation by the degs-degu signalling system. using sacxy'-lacz and sacx'-lacz fusions, we show that the transcription of the sacx and sacy genes is both inducible by sucrose and regulated by degu. sacx and sacy appear to constitute an operon, since the deletion of the sacx leader region abolished the ...19921400159
stabilization of phosphorylated bacillus subtilis degu by degr.the production of bacillus subtilis extracellular proteases is under positive and negative regulation. the functional role of degr, one of the positive regulators, was studied in relation to the degs and degu gene products, which belong to the bacterial two-component regulatory system. studies with a translational fusion between the escherichia coli lacz and the bacillus subtilis subtilisin (apre) genes indicated that the stimulatory site of degr lay upstream of position -140, with the region up ...19921459944
promoter elements required for positive control of transcription of the escherichia coli uhpt gene.the uhpabct locus of escherichia coli encodes the transport system which allows the cell to accumulate a variety of sugar phosphates in unaltered form. the expression of uhpt, the gene encoding the transport protein, is regulated by the uhpabc gene products. the uhpa protein is required for expression; its deduced amino acid sequence shows that it belongs to a subfamily of bacterial transcription regulators including narl, degu, and fixj. members of this subfamily have an amino-terminal phosphor ...19921569008
sequence and properties of comq, a new competence regulatory gene of bacillus subtilis.the sequence and properties of the comq gene are described. comq was predicted to encode a 34,209-da protein, and the product of comq was shown to be required for the development of genetic competence. the apparent transcriptional initiation and termination sites of comq were mapped, and the location of a likely e sigma a promoter was inferred. the expression of comq was maximal early in growth and declined as the cells approached the stationary phase. this expression was not dependent on any of ...19911715859
mutational analysis of the bacillus subtilis degu regulator and its phosphorylation by the degs protein kinase.the degs-degu protein kinase-response regulator pair controls the expression of genes encoding degradative enzymes as well as other cellular functions in bacillus subtilis. both proteins were purified. the degs protein was autophosphorylated and shown to transfer its phosphate to the degu protein. phosphoryl transfer to the wild-type degu protein present in crude extracts was shown by adding 32p-labeled degs to the reaction mixture. under similar conditions, the modified proteins encoded by the ...19911901568
altered phosphorylation of bacillus subtilis degu caused by single amino acid changes in degs.the bacillus subtilis sacu locus consists of the degs and degu genes, which play a major role in controlling the production of degradative enzymes including extracellular proteases. degs has been shown to be autophosphorylated and to transfer the phosphoryl group to degu. in this study, we partially purified the degs proteins which carry amino acid changes resulting from various mutations and examined the phosphorylation reaction. the mutations used were degs42, causing a reduction in exoproteas ...19911909319
mutational analysis of nitrate regulatory gene narl in escherichia coli k-12.the narl gene product, narl, is the nitrate-responsive regulator of anaerobic respiratory gene expression. we used genetic analysis of narl mutants to better understand the mechanism of narl-mediated gene regulation. we selected and analyzed seven nitrate-independent narl mutants. each of three independent, strongly constitutive mutants had changes of val-88 to ala. the other four mutants were weakly constitutive. the narl505(v88a) allele was largely dominant to narl+, while narx+ had a negative ...19912066339
isolation and phosphorylation of the bacillus subtilis degs and degu gene products.the bacillus subtilis sacu locus consists of two genes, degs and degu, which positively regulate the synthesis of several extracellular enzymes including the neutral and alkaline proteases. both the degs and degu proteins have been purified from overproducing escherichia coli strains harboring degs or degu gene-carrying plasmids, and the following results were obtained. degs was autophosphorylated in the presence of [gamma-32p]atp, and transferred the phosphoryl group to degu. the transfer react ...19902123196
further studies on the understanding of octodon degus natural resistance to morphine: a comparative study with the wistar rat.1. octodon degus shows higher levels of tolerance to morphine when compared with the wistar rat. 2. in the formalin algesiometric test, this caviomorph is more resistant to pain (p less than 0.01) and to the analgesic effect of morphine (p less than 0.001). 3. cd50 and ld50 were significantly higher in octodon degus as compared with wistar rat. 4. morphine caused in rat severe hypotension, while doses eight times higher in o. degus had a transient effect. 5. 3h-naloxone binding in adrenal glands ...19892565188
drug tolerance and detoxicating enzymes in octodon degus and wistar rats. a comparative study.octodon degus shows greater tolerance to pentobarbital as compared with the wistar rat. mixed function oxidase activities in liver microsomes were higher in octodon degus than in the wistar rat. the reactions assayed were: aminopyrine n-demethylation, aniline and naphthalene hydroxylation and p-nitroanisole o-demethylation. these higher activities seem to be due mainly to the greater cytochrome p-450 content of liver microsomes of octodon degus. glutathione s-transferase activity towards 1-chlor ...19852858344
comparative water economy of sympatric rodents in a chilean semi-arid habitat.1. water requirements, water balance components and dependence on exogenous water were estimated in four species of sympatric rodents inhabiting a chilean semi-arid region. 2. a significant increase in free water drinking was observed in all rodents when the diet composition was changed from 14 to 20% protein. 3. under water balance conditions the cricetid species (phyllotis darwini, oryzomys longicaudatus and akodon olivaceus) showed 1.66 to 1.88 times the weight-specific daily water gain of oc ...19882907435
epidemiology of chagas' disease in northern chile: isozyme profiles of trypanosoma cruzi from domestic and sylvatic transmission cycles and their association with cardiopathy.trypanosoma cruzi was isolated from 98 patients, 59 triatoma infestans, 51 triatoma spinolai, and 1 octodon degus from northern chile. with few exceptions, stocks originating from domestic hosts were classified, based on their isozyme profile, as principal zymodeme (z)2, while sylvatic stocks from t. spinolai and the rodent o. degus showed z1 profiles. these results indicate the existence of separate domestic and sylvatic transmission cycles. clinical data and t. cruzi isozyme profiles from 107 ...19873116867
progesterone-binding proteins in plasma of guinea-pigs and other hystricomorph rodents.progesterone-binding plasma proteins (pbpp, progesterone-binding globulin, pbg, and corticosteroid binding globulin, cbg) have been measured in plasma of guinea-pigs, casiragua, cuis, degu and plains viscacha. during pregnancy pbpp increased to reach peak values between days 20-25 and days 50-term in guinea-pigs, immediately before parturition in casiragua, and in mid-gestation in cuis, degu and viscacha. the pattern of pbpp concentration during pregnancy was similar to that of plasma progestero ...19816170753
isozyme heterogeneity and numerical taxonomy of trypanosoma cruzi stocks from chile.fifty-three stocks of trypanosoma cruzi were isolated in chile, 13 from patients, 32 from the domestic triatomine vector triatoma infestans, and 8 from the silvatic and peridomestic vector t. spinolai. the majority of isolates from triatomine bugs were made by the direct culture of infected faeces. the 53 stocks and a single clone were characterized by a combination of starch-gel and cellulose acetate enzyme electrophoresis. three groups of t. cruzi stocks were apparent from either simple visual ...19846237475
angiotensin iii-induced dipsogenic and pressor responses in rodents.subcutaneous injections of [des-asp1]-angiotensin i [( des-asp1]-ai), angiotensin ii (aii), and angiotensin iii (aiii) induced drinking in the laboratory rat and the south american rodent octodon degus, but not in the gerbil. in a second experiment, pretreatment with captopril, an angiotensin converting enzyme inhibitor, prevented the endogenous conversion of subcutaneously injected [des-asp1]-ai to aiii and prevented drinking in rats and degus. the pharmacological artifact of hypovolemia caused ...19846380522
a comparative study in twelve mammalian species of volume densities, volumes, and numerical densities of selected testis components, emphasizing those related to the sertoli cell.morphometric studies were performed on 12 mammalian species (degu, dog, guinea pig, hamster, human, monkey, mouse, opossum, rabbit, rat, stallion, and woodchuck) to determine volume density percentage (vv%), volume (v), and numerical density (nv) of seminiferous tubule components, especially those related to the sertoli cell, and to make species comparisons. for most species, measurements were taken both from stages where elongate spermatids were deeply embedded within the sertoli cell and from ...19902111966
growth stage signal transduction and the requirements for srfa induction in development of competence.srfa is an operon needed for the development of genetic competence in bacillus subtilis. this operon is normally expressed at a low level during growth, and its transcription increases sharply just before the transition to stationary phase. the genetic requirements for the full expression of srfa were previously examined in several laboratories and shown to include spo0a, spo0h, spo0k, comq, and coma. in the present study these results were confirmed with an isogenic set of strains. we have also ...19911938922
the primary role of coma in establishment of the competent state in bacillus subtilis is to activate expression of srfa.the establishment of genetic competence in bacillus subtilis requires the genes of the competence regulon which function in the binding, processing, and transport of dna. their expression is governed by multiple regulatory pathways that are composed of the coma, comp, sin, abrb, spo0h, spo0k, spo0a, degu, and srfa gene products. among these, srfa is thought to occupy an intermediate position in one of the pathways that controls late competence gene expression. the full expression of srfa require ...19911938921
salt stress is an environmental signal affecting degradative enzyme synthesis in bacillus subtilis.growth under conditions of salt stress has important effects on the synthesis of degradative enzymes in bacillus subtilis. salt stress strongly stimulates the expression of sacb, encoding levansucrase (about ninefold), and downregulates the expression of apre, encoding alkaline protease (about sixfold). it is suggested that the degs-degu two-component system is involved in sensing salt stress. moreover, it has been shown that the level of sacb expression strongly depends on the growth conditions ...19957730271
expression of the atp-dependent deoxyribonuclease of bacillus subtilis is under competence-mediated control.transcription of the atp-dependent deoxynuclease operon (addab), as monitored by means of an addab-lacz transcriptional fusion, has a low, constitutive level and is initiated from a sigma a type promoter. transcription of addab is independent of dna-damaging agents known to induce the sos response in bacillus subtilis. however, addab transcription increased significantly during competence development. this competence-specific induction was dependent on the gene products of srfa, degu and comk, b ...19957746142
cloning and sequencing the degs-degu operon from an alkalophilic bacillus brevis.the sacu region from an alkalophilic bacillus brevis was cloned and sequenced. the two open reading frames of the degs-degu operon encode polypeptides that gave calculated molecular masses of 43.8 kda and 27.0 kda, respectively. sequence comparisons at the amino acid level to the b. subtilis degs-degu genes showed 74% and 84% similarity, respectively. on a multicopy vector the b. brevis degs-degu genes were found to cause hypersecretion of several extracellular enzymes in a b. subtilis rec- stra ...19947765823
molecular biology of islet amyloid polypeptide.we investigated the relationship between non-insulin-dependent diabetes mellitus (niddm) and islet amyloid polypeptide (iapp) gene by restriction fragment length polymorphism (rflp) and polymerase chain reaction (pcr)-direct sequencing analysis. endonuclease bglii and/or pvuii rflp analysis revealed no positive correlation of iapp gene with niddm. in pcr-direct sequencing of 25 niddm patients, no nucleotide sequence differences were found. these data do not support the view that iapp plays an im ...19921371737
the pineal gland of the trumpet-tailed rat (octodon degus).the structure and ultrastructure of the pineal gland of the degu or trumpet-tailed rat (octodon degus), a rodent inhabiting tropical-equatorial areas, was examined under light and electron microscopy. on the basis of its form, size, and location, the pineal gland of the degu is classified as a proximal or "a" type. the connective tissue appeared poorly developed and the gland contained non-fenestrated capillaries. a single population of typical pinealocytes was found. in addition, a small number ...19921287193
effect of degs-degu mutations on the expression of sigd, encoding an alternative sigma factor, and autolysin operon of bacillus subtilis.primer extension analysis of transcripts of the bacillus subtilis autolysin (cwlb) operon indicated that sigd-dependent transcripts from the pd promoter are missing in the degu32(hy) and degs200 (hy) mutants. the degu32(hy) mutation caused a 99% reduction in the expression of a sigd-lacz translational fusion gene constructed in the b. subtilis chromosome. the phosphorylated form of the degu protein seems to be a regulator for expression of the sigd gene.19947914190
preparation of rhinovirus antisera in the south american hystricomorph rodent, octodon degus (38507).rhinovirus antisera have been prepared for rhinoviruses (rv) 7,9,26,32,67 and 87 in guinea pigs and in degus. titers achieved were either similar in the 2 animals (rv7) somewhat higher in the degu (rv9 and rv32) or clearly higher in the degu (rv26, rv67 and rv87). specificity of the antisera was similar in both animals. in special instances where it is difficult to prepare high-titered rhinovirus antisera in the guinea pig, the degu offers an attractive alternative source.1975165524
physiological and genetic characterization of the osmotic stress response in bacillus subtilis.bacillus subtilis cultures submitted to an osmotic upshock (1.5 m nacl) lysed unless stationary phase had been reached. several physiological variations were observed, such as delayed growth (adaptation), a filamentous bacterial appearance, reca-dependent osmoresistance (sos), and cross-induction by a previous stress (heat shock). osmoresistance and sporulation seem to share pathways of regulation such as inhibition in the presence of glucose and glutamine and derepression in a catabolite-resist ...19948019936
multiple copies of the prob gene enhance degs-dependent extracellular protease production in bacillus subtilis.bacillus subtilis secretes extracellular proteases whose production is positively regulated by a two-component regulatory system, degs-degu, and other regulatory factors including degr. to identify an additional regulatory gene(s) for exoprotease production, we performed a shotgun cloning in the cell carrying multiple copies of degr and found a transformant producing large amounts of the exoproteases. the plasmid in this transformant, plc1, showed a synergistic effect with multiple copies of deg ...19948083159
the distribution of angiotensin ii binding sites in rodent brain.the distribution of specific angiotensin ii (aii) binding capacity of several brain regions, pituitary, and adrenals was determined in 6 rodent species namely rats, mice, hamsters, kangaroo rats, gerbils and degus. rats and mice had similar distributions with the highest levels of binding observed in the area postrema, septum and superior colliculi. low levels were seen in the cortex, cerebellum, striatum and hippocampus. other areas had intermediate levels. the distribution of aii binding in ge ...19816258713
new differences between the wistar rat and octodon degus, a putative laboratory animal resistant to morphine.1. the effects of cns depressants (methadone and alcohol) and natural neurotransmitters (na and ach) are studied in o. degus. 2. o. degus shows resistance to methadone in the formalin algesiometric test and eeg. 3. ethanol elimination profile suggest the presence of an atypical alcohol dehydrogenase in o. degus 4. o. degus is extremely resistant to the pressor effects of noradrenaline 5. the isolated atrium of this rodent is 40 times more sensitive to the negative chronotropic effect of methadon ...19892572391
stabilization of the phosphorylated form of bacillus subtilis degu caused by degu9 mutation.a bacillus subtilis response regulator, degu9, carrying an amino acid alteration caused by the degu9(hy) mutation was partially purified and phosphorylation and dephosphorylation of the protein was studied. the extent of phosphorylation was not as high as the level attained with wild-type degu, but the degu9-phosphate once formed was more stable that the wild-type degu-phosphate. an in vivo study with a degu9 mutant showed that degs was necessary for the overproduction of exoproteases. these res ...19948125252
the spooa and degu genes of bacillus subtilis show genetic homology.the transformation efficiency of competent bacillus subtilis degu32(hy) strains was found to depend on the marker that was selected. prototrophic transformants were obtained at frequencies similar to those in the wild type control, but spo- transformants were rare also when a spooa::erm insertion that produces a selectable marker (ermr) was used. the ermr transformants obtained within the degu32(hy) background were spo+ and had lost the characteristics of the degu(hy) parental recipient strain i ...19938386124
cloning of complementary dnas encoding islet amyloid polypeptide, insulin, and glucagon precursors from a new world rodent, the degu, octodon degus.the degu, octodon degus, is a south american hystricomorph rodent that is of interest because it develops spontaneous diabetes mellitus and has been found to have islet amyloidosis. to help clarify these problems we have cloned cdnas encoding islet amyloid polypeptide (iapp), insulin, and glucagon precursors from this species. the predicted amino acid sequence of degu iapp is very similar to that of nonamyloid-forming guinea pig iapp. in contrast, degu insulin and the c-terminal region of degu g ...19902293024
effects of elevated temperature on the epididymis and testis: experimental studies.the effects of temperature on the male tract have been examined in the rat, rabbit and hamster, as well as other species that include a naturally cryptorchid rodent, the degu, and an insectivore, the musk shrew. in principle, a small increase in the temperature of the testis does not destroy the germinal epithelium; however, it reduces testis weight and sperm production and brings a greater incidence of morphologically abnormal spermatids and spermatozoa. this demonstrates that the testis can be ...19912042501
comparison of the body temperature rhythms of diurnal and nocturnal rodents.the daily rhythm of body temperature of six rodent species, three of them nocturnal (rattus norvegicus, mesocricetus auratus, and meriones unguiculatus) and three diurnal (octodon degus, spermophilus tridecemlineatus, and s. richardsoni), was studied by telemetry under a 14l:10d light-dark cycle. significant interspecies differences were found in the mean level (range: 36.0-37.4 degrees c), amplitude (range: 2.1 degrees-4.3 degrees c), robustness (range: 115-185 qp), and acrophase (range: 8.5-16 ...19968708632
drug metabolism in octodon degus: low inductive effect of phenobarbital.1. differential effects of phenobarbital pre-treatment on liver microsomal drug metabolizing enzymes were registered in octodon degus. 2. glucuronidation reaction for morphine was decreased but that for p-nitrophenol was significantly increased. 3. oxidative reactions such as naphthalene hydroxylation, morphine and aminopyrine n-demethylation were modestly increased. 4. in phenobarbital treated octodon degus, testosterone metabolic pathways were decreased, not inducible or absent. 5. spectral st ...19901980879
degs-degu and comp-coma modulator-effector pairs control expression of the bacillus subtilis pleiotropic regulatory gene degq.production of a class of both secreted and intracellular degradative enzymes in bacillus subtilis is regulated at the transcriptional level by a signal transduction pathway which includes the degs-degu two-component system and at least two additional regulatory genes, degq and degr, encoding polypeptides of 46 and 60 amino acids, respectively. expression of degq was shown to be controlled by degs-degu. this expression is decreased in the presence of glucose and increased under any of the followi ...19911901055
plasmid-amplified coms enhances genetic competence and suppresses sinr in bacillus subtilis.the establishment of genetic competence in bacillus subtilis is controlled by a vast signal transduction network involving the products of genes that function in several postexponential-phase processes. two of these proteins, sinr and degu, serve as molecular switches that influence a cell's decision to undergo either sporulation or genetic competence development. in order to determine the roles of sinr and degu in competence control, multicopy suppression experiments with plasmid-amplified coms ...19968752331
signal transduction pathway controlling synthesis of a class of degradative enzymes in bacillus subtilis: expression of the regulatory genes and analysis of mutations in degs and degu.the rates of synthesis of a class of both secreted and intracellular degradative enzymes in bacillus subtilis are controlled by a signal transduction pathway defined by at least four regulatory genes: degs, degu, degq (formerly sacq), and degr (formerly prtr). the degs-degu proteins show amino acid similarities with two-component procaryotic modulator-effector pairs such as ntrb-ntrc, chea-chey, and envz-ompr. by analogy with these systems, it is possible that degs is a protein kinase which coul ...19901688843
regulatory inputs for the synthesis of comk, the competence transcription factor of bacillus subtilis.competence in bacillus subtilis is expressed post-exponentially in response to signals which are interpreted by a complex network of regulatory proteins. this network culminates in the transcriptional activation of a set of late-competence proteins that mediate dna binding and uptake during transformation. comk, a protein that binds to competence promoters and appears to activate their transcription, is itself synthesized in response to the signal-transduction network. comk is known to be requir ...19968878039
bacillus subtilis can modulate its capacity and specificity for protein secretion through temporally controlled expression of the sips gene for signal peptidase i.bacillus subtilis contains three chromosomally encoded type i signal peptidases (sips, sipt and sipu), which remove signal peptides from secretory precursor proteins. in the present study the biological function of sips and the regulation of its synthesis were analysed. unlike the type i signal peptidase of escherichia coli, sips was essential neither for protein secretion nor viability of the cell. however, in the absence of sips the rate of processing of several preproteins was reduced, and fo ...19968951809
the degs/degu and comp/coma two-component systems are part of a network controlling degradative enzyme synthesis and competence in bacillus subtilis. 19947855425
the phosphorylation state of the degu response regulator acts as a molecular switch allowing either degradative enzyme synthesis or expression of genetic competence in bacillus subtilis.two classes of mutations were identified in the degs and degu regulatory genes of bacillus subtilis, leading either to deficiency of degradative enzyme synthesis (degs or degu mutations) or to a pleiotropic phenotype which includes overproduction of degradative enzymes and the loss of genetic competence (degs(hy) or degu(hy) mutations). we have shown previously that the degs protein kinase and the degu response regulator form a signal transduction system in b. subtilis. we now demonstrate that t ...19921321152
[first observations on the variations of parasitic helminth populations from the chilean rodent octodon degus (author's transl)]. 1976962983
the ultrastructure of the trophoblastic layer of the degu (octodon degus) placenta: a re-evaluation of the 'channel problem'.previous studies on immersion-fixed specimens of the haemomonochorial labyrinthine chorioallantoic placenta of the degu have made visible channels or pores which completely crossed the trophoblastic layer; for the first time hints for an open connection between maternal blood spaces and fetal interstitium were demonstrated in a placenta. this important finding was re-evaluated by means of transmission electron microscopy paying particular attention to the influence of the mode of fixation and of ...19979089785
gas chromatographic/mass spectrometric evidence for the identification of a heptitol and an octitol in human and octodon degu eye lenses.gas chromatographic analysis of alditols obtained from post-mortem human and south american rodent octodon degu eye lenses indicated the presence of two high molecular weight, late eluting components which could not be identified. thus, the samples were subjected to gas chromatographic/mass spectrometric analysis under both electron impact and chemical ionization conditions. the data obtained from these analyses indicate that both human and octodon degu lenses contain a heptitol and an octitol, ...19836651856
enhanced metabolism of morphine in octodon degus compared to wistar rats.comparative studies of the actions of morphine in different mammals have shown that octodon degus presents an unusual tolerance to this compound. morphine glucuronidation and n-demethylation in microsomal fractions of octodon degus were 10.9 and 50.0 nmol of product formed/min/g of wet liver, respectively. in wistar rat these activities were 10.5 and 12.5, respectively. microsomal protein and cytochrome p-450 contents were two and four times higher in octodon degus than in the wistar rat, respec ...19846510676
a new bacillus subtilis gene, med, encodes a positive regulator of comk.bacillus subtilis degr, a positive regulator of the production of degradative enzymes, is negatively regulated by the competence transcription factor comk which is overproduced in meca null mutants. we used transposon tn10 to search for a mutation that reduced the repression level of degr caused by a meca mutation. a new gene exerting positive regulation on comk was obtained and designated med (suppressor of meca effect on degr). sequence determination, northern analysis, and primer extension an ...19979335269
comk acts as an autoregulatory control switch in the signal transduction route to competence in bacillus subtilis.the comk gene is a regulatory transcription unit which is essential for the development of genetic competence in bacillus subtilis. the transcription of comk is under strict nutritional and growth phase-dependent control and has been shown to depend on the gene products of coma and srfa. in this report, we show that expression of comk is dependent on its own gene product as well as on the gene products of all other tested regulatory genes known to be involved in competence development (abrb, com ...19948083168
angiotensin's contribution to dipsogenic additivity in several rodent species.significant positive correlations were obtained between plasma angiotensin levels and drinking following the administration of polyethylene glycol (peg) in rats, gerbils, and hamsters and following isoproterenol (isop) in rats and gerbils, but not in a south american rodent, octodon degus (degus). hamsters revealed elevations in plasma angiotensin following isop but no drinking, whereas degus failed to show changes in plasma angiotensin to either treatment, although drinking occurred following p ...19873606809
water intake of djungarian and syrian hamsters treated with various dipsogenic stimuli.djungarian and syrian hamsters were found to exhibit robust water intake following water deprivation, and in response to hyperosmotic and hypovolumetric challenges to body fluids following injections of hypertonic nacl and polyethylene glycol, respectively. water intake was not stimulated following peripheral injections of isoproterenol, serotonin, or angiotensins ii or iii. both hypovolema and isoproterenol activated the renin-angiotensin system. this profile of drinking responses in hamsters i ...19883237800
cataract prevention in diabetic octodon degus with pfizer's sorbinil.the octodon degus has been reported to have higher aldose reductase activity in the lens compared to the gerbil and rat. when made diabetic the degus develop cataracts within 4 weeks. we have been able to completely prevent cataract formation in diabetic degus using pfizer's sorbinil for up to 6 months. this is further evidence of the role of aldose reductase in the formation of cataracts in diabetes.19892523284
functional organization of the auditory cortex in a native chilean rodent (octodon degus).the tonotopic organization of primary auditory cortex (ai) and surrounding secondary regions has been studied in the octodon degus using standard microelectrode mapping techniques. the results confirm and extend previous observations made in other species. the tonotopic organization of the largest field (ai) apparently covered the hearing range of o. degus. low tonal frequencies were represented rostroventrally and high frequencies caudally, with isofrequency contours orientated dorsoventrally i ...19979711324
in bacillus subtilis degu-p is a positive regulator of the osmotic response.the osmosensitivity presented by spo0a and degu null mutant strains of bacillus subtilis pointed to their protein products as essential regulators for the osmotic response. this was further investigated by analyzing their transcription activity. the results showed that both spo0a-lacz and degsu-lacz were induced by the hypertonic medium. the actual phosphorylation state of these proteins was also analyzed by the bias of two reporter gene promoters activity (abrb-lacz and degq-lacz). the absence ...19989806973
on the organization of the retino-tecto-thalamo-telencephalic pathways in a chilean rodent; the octodon degus.after performing eye enucleations or restricted lesions in the superior colliculus or the pulvinar nucleus, the degeneration patterns provoked by these procedures were analyzed by means of the nissl and the fink-heimer methods in 30 specimens of octodon degus. the pulvinar or lateroposterior nucleus can be subdivided into 3 regions (rostrolateral, rostromedial and caudal), on the basis of cytoarchitecture, tectofugal afferent and efferent connections to the cerebral cortex. in addition, this nuc ...19827059825
elucidation of regulatory elements that control damage induction and competence induction of the bacillus subtilis sos system.a novel consensus sequence (gaac-n4-gttc) has been identified within the promoter regions of dna damage-inducible (din) genes from bacillus subtilis. this sequence has been proposed to function as an operator site that is required for regulation of the sos system of b. subtilis. to test this hypothesis, a deletion analysis of the dina and reca promoter regions was utilized. a single consensus sequence is sufficient and necessary for damage-inducible regulation of the dina and reca promoters. del ...19937690748
the influence of fibre in the diet on growth rates and the digestibility of nutrients in the greater cane rat (thryonomys swinderianus).the greater cane rat thryonomys swinderianus is a coprophagous rodent in which fermentation occurs in the large caecum. the extent to which a 45% increase in the fibre component of the diet influenced growth rates of cane rats and the digestibility of nutrients and energy was investigated in two feeding trials. higher fibre levels in the diet reduced the digestibility of dry matter, protein and fat, while animals digested fibre components (neutral-detergent fibre, acid detergent fibre, hemicellu ...199910425732
a degu-containing sp beta prophage complements superactivator mutations affecting the bacillus subtilis degsu operon.the bacillus subtilis degsu two-gene operon encodes a two-component regulatory system which positively controls expression of a variety of genes encoding degradative enzymes. point superactivator mutations in either degs or degu increase the production of these enzymes. a specialized transducing sp beta phage which partially complements several of these mutations was isolated from a phage library of the b. subtilis chromosome. this phage was shown to contain the degu (wild-type) gene. this unexp ...19921475517
a novel member of the subtilisin-like protease family from bacillus subtilis.aprx is a 1326 bp gene of bacillus subtilis strain 168 that encodes a serine protease, probably intracellular, characterized by significant similarity with subtilisins, thermitases and pyrolysins. transcription analysis, performed by rt-pcr and primer extension, allowed the localization of the active promoter and showed that aprx is expressed in stationary phase. the pattern of expression of aprx and its dependence on various transition state regulatory genes (degu, degq, hpr, abrb, sinr), monit ...199910589719
the regulation of competence transcription factor synthesis constitutes a critical control point in the regulation of competence in bacillus subtilis.comk, which encodes the competence transcription factor, is itself transcriptionally activated at the transition from exponential growth to stationary phase in bacillus subtilis. meca, a negative regulator of competence, also inhibits comk transcription when overexpressed, and a meca null mutation results in comk overexpression. although null mutations in meca, as well as in another gene, mecb, are known to bypass the requirements for nearly all of the competence regulatory genes, the comk requi ...19948083167
gas chromatographic analysis of lens monosaccharides.gas-liquid chromatography was employed to determine free monosaccharides in human, rat, and south american rodent octodon degu lenses. in addition to d-glucose, d-fructose, sorbitol and myo-inositol, which were previously known to be components of lens tissue, glycerol, erythritol, threitol, ribitol, xylitol, and mannitol were also detected in the lenses of these three species. the concentrations in lenses of these three species were in the following ranges: glycerol 1.2 to 40 mumol/gm wet tissu ...19846690636
regulation of hrp genes and type iii protein secretion in erwinia amylovora by hrpx/hrpy, a novel two-component system, and hrps.two novel regulatory components, hrpx and hrpy, of the hrp system of erwinia amylovora were identified. the hrpxy operon is expressed in rich media, but its transcription is increased threefold by low ph, nutrient, and temperature levels--conditions that mimic the plant apoplast. hrpxy is autoregulated and directs the expression of hrpl; hrpl, in turn, activates transcription of other loci in the hrp gene cluster (z.-m. wei and s. v. beer, j. bacteriol. 177:6201-6210, 1995). the deduced amino -a ...200011059492
transcription of bacillus subtilis degr is sigma d dependent and suppressed by multicopy prob through sigma d.production of bacillus subtilis exoproteases is positively regulated by the degs-degu two-component regulatory system and other regulatory factors including degr and prob. it was shown that the expression of degr was virtually abolished in a sigd mutant and that the transcriptional initiation site in vivo is preceded by a sequence very similar to the consensus sequence of sigma d-recognized promoters. alteration of the -10 sequence of the putative promoter greatly reduced the expression of degr. ...19968550420
suppression of early competence mutations in bacillus subtilis by mec mutations.although competence normally develops only in glucose-minimal salts media, meca and mecb mutations permit the expression of competence and of late competence genes in complex media as well (d. dubnau and m. roggiani, j. bacteriol. 172:4048-4055, 1990). the expression of late competence genes is dependent on the products of the regulatory genes coma, comb, comp, sin, abrb, spo0h, and spo0a. we show here that this list must be extended to include degu, csh-293, and spo0k. meca and -b mutations byp ...19902113920
rodent models of congenital and hereditary cataract in man.because the organogenesis and physiology of the lens are essentially similar in various mammals, an understanding of the etiology and pathogenesis of the formation of cataract in an animal model will enhance our knowledge of cataractogenesis in man. in this review, we summarize the background, etiology, and pathogenesis of cataracts that occur in rodents. the main advantages of using rodent mutants include the well-researched genetics of the animals and the comparative ease of breeding of large ...19911958636
involvement of stringent factor rela in expression of the alkaline protease gene apre in bacillus subtilis.expression of bacillus subtilis apre, encoding an extracellular alkaline protease, is positively regulated by phosphorylated degu, the regulator of a two-component regulatory system, degs-degu. we found that the expression of an apre'-'lacz fusion was greatly reduced in a disruption mutant with a mutation of rela, which encodes the stringent factor rela. the level of degu in the rela mutant was similar to that in the wild-type cell. a rela degu double mutation did not result in a further decreas ...200111443101
expression of the subtilisin carlsberg-encoding gene in bacillus licheniformis and bacillus subtilis.the cloning and sequence of the 5' untranslated region (5'-utr) of the bacillus licheniformis (bl) 6816 subtilisin carlsberg gene (subc) are reported here. the 5' and 3' ends of subc transcripts were characterized, and the promoter identified. expression was studied using a fused lacz reporter gene integrated into the chromosome of heterologous host bacillus subtilis (bs). beta gal activities of mutants deleted within the promoter region identified a region which is required for stimulation by t ...19957828931
bacillus subtilis degu acts as a positive regulator for comk expression.bacillus subtilis comk plays a critical role in competence development. we report that b. subtilis degr, a positive regulator for exoenzyme production, is negatively regulated by overproduced comk caused by a meca null mutation. to identify a positive regulator for comk expression in the meca background, mutations that allowed the degr gene to be expressed were screened in tn10 transposon insertion mutants. as a result, we identified degu insertion mutations as those having such a property. the ...19968955341
comprehensive dna microarray analysis of bacillus subtilis two-component regulatory has recently been shown through dna microarray analysis of bacillus subtilis two-component regulatory systems (degs-degu, comp-coma, and phor-phop) that overproduction of a response regulator of the two-component systems in the background of a deficiency of its cognate sensor kinase affects the regulation of genes, including its target ones. the genome-wide effect on gene expression caused by the overproduction was revealed by dna microarray analysis. in the present work, we newly analyzed 24 ...200111717295
stress related changes of cell surface hydrophilicity in bacillus subtilis.the changes of cell surface hydrophilicity in bacillus subtilis were analyzed in response to oxygen-limitation, heat shock, salt stress, ph-shock, phosphate- and carbon-limitation. although cell surface hydrophilicity varied during growth phases, an increase of surface hydrophilicity was observed under several of these stress conditions. an observed drop in intracellular gtp and/or atp may be an element of the signal transduction pathway leading to an increase in surface hydrophilicity in respon ...200212073823
effects of the sinr and degu32 (hy) mutations on the regulation of the apre gene in bacillus subtilis.the apre gene of bacillus subtilis codes for the serine alkaline protease known as subtilisin. its expression is regulated by a complex network of activators and repressors that includes the products of hpr, degu and sinr. in order to understand the effect of these gene products on subtilisin expression, strains carrying combinations of the degu32(hy), hpr2 and sinr null mutations, were constructed. we found that in all the genetic backgrounds tested, the sinr null mutation decreased apre expres ...19979065689
mecb of bacillus subtilis, a member of the clpc atpase family, is a pleiotropic regulator controlling competence gene expression and growth at high temperature.the bacillus subtilis degs-degu histidine kinase-response regulator pair controls the expression of genes encoding degradative enzymes such as levansucrase (sacb) and of genes involved in genetic competence. the meca and mecb mutations were previously isolated as allowing competence gene expression in complex media. we have shown that the mec mutations also lead to overexpression of sacb, bypassing the degs-degu requirement. this expression was shown to be entirely dependent upon comk, a positiv ...19948016066
the induction of fos-like proteins in the suprachiasmatic nuclei and intergeniculate leaflet by light pulses in degus (octodon degus) and nocturnal rodents, exposure to light results in an increase in fos expression in two regions that receive direct retinal input: the suprachiasmatic nuclei (scn) of the hypothalamus and the intergeniculate leaflet (igl) of the thalamus. the induction of fos within the scn of nocturnal rodents is phase dependent, with light presented during the subjective night increasing fos expression and light presented during the subjective day having little effect. by contrast, fos expression increases in ...19979376639
functional analysis of the secretory precursor processing machinery of bacillus subtilis: identification of a eubacterial homolog of archaeal and eukaryotic signal peptidases.approximately 47% of the genes of the gram-positive bacterium bacillus subtilis belong to paralogous gene families. the present studies were aimed at the functional analysis of the sip gene family of b. subtilis, consisting of five chromosomal genes, denoted sips, sipt, sipu, sipv, and sipw. all five sip genes specify type i signal peptidases (spases), which are actively involved in the processing of secretory preproteins. interestingly, strains lacking as many as four of these spases could be o ...19989694797
species differences in the localization of neuropeptide ff receptors in rodent and lagomorph brain and spinal cord.quantitative in vitro receptor autoradiography of [125i][d-tyr1,(nme)phe3]npff was used to study the regional distribution of neuropeptide ff receptors in rodent and lagomorph brain. in rat, mouse, rabbit, and afghan pika [125i][d-tyr1,(nme)phe3]npff binding sites were enriched in the superficial layers of dorsal horn of the spinal cord and in parabrachial nucleus, central gray matter, hypothalamus, and reunions thalamic nucleus. in other neuroanatomical regions, important species differences in ...19968735965
the bacillus subtilis transition state regulator abrb binds to the -35 promoter region of comk.genetic competence is a differentiation process initiated by bacillus subtilis as a result of nutritional deprivation, and is controlled by a complex signal transduction cascade. the promoter of comk, encoding the competence transcription factor, is regulated by at least four different transcription factors: rok, cody, degu and comk itself. genetic data have shown that comk expression is influenced by the transition state regulator abrb as well. in this paper we show that abrb binds specifically ...200312586407
arterial vascularization of the abdominal and pelvic regions in the degu, octodon degus (rodentia, octodontidae).the abdominal and the pelvic arterial supply of the degu, octodon degus, were described in 19 specimens (10 males and 9 females) from a laboratory strain. animals were injected through the left ventricle of the heart with coloured latex solution and subsequently dissected under a surgical microscope. the arrangement and variations of the visceral and muscular arteries were described. comparative analysis among rodents revealed that, even though there was a wide range of interspecific variation i ...19968712380
lupus-erythematosus-like eruption induced by trichophyton mentagrophytes infection.several factors are known to trigger acute manifestations of lupus erythematosus (drugs, ultraviolet radiation, bacterial or viral infections, pregnancy), but fungal infections have never been reported to induce lupus-like lesions. we describe 2 children with tinea capitis caused by trichophyton mentagrophytes(tm), who developed transient skin and serological manifestations of systemic lupus erythematosus.200312771470
retinal projection to the dorsal raphe nucleus in the chilean degus (octodon degus).a substantial projection from the retina to the dorsal raphe nucleus (drn) has been demonstrated in the chilean degus, a diurnal/crepuscular hystricomorph rodent. following intraocular injection of cholera toxin subunit b (ctb), immunocytochemically labeled ctb-positive axons and terminals were observed in all major retinorecipient nuclei as well as in the drn and periaqueductal gray (pag) of the mesencephalon. two streams of optic axons to the drn were observed: one descending from the optic tr ...200111259770
binding of response regulator degu to the apre promoter is inhibited by rapg, which is counteracted by extracellular phrg in bacillus subtilis.we screened the putative rap-phr (response regulator aspartyl-phosphate phosphatase-phosphatase regulator) systems identified in the bacillus subtilis genome for a rap gene that affects apre (alkaline protease gene) expression by using a multicopy plasmid. we found that rapg was involved in the regulation of apre, which belongs to the regulon of degu, the response regulator of the degs-degu two-component system. disruption of rapg and phrg resulted in enhancement and reduction of apre-lacz expre ...200312950930
[presence of linguatula serrata froelich, 1789, in dusycion culpaeus and of nymphal forms in octodon d. degus and abrocoma b. benetti]. 196013793027
rhythm chronotypes in a diurnal rodent, octodon degus.interindividual variations in entrained human circadian rhythms and their relationship to differences in ease of adjustment to phase shifts have been well described. humans classified as morning type (mt) display phase-advanced temperature minimum, onset of daily activity, and onset of sleep, whereas evening type (et) individuals demonstrate the opposite pattern with a later phase angle of entrainment for these measures. we examined 15 variables of circadian activity and temperature for diurnal ...19979321886
[the genetical effects of degus gene in bacillus subtilis ki-2-132].using the methods of recombination and gene disruption, the effects of degus gene in bacillus subtilis ki-2-132 were studied. the results showed that the gene could affect all protease-producing, competence formation, cell mobility and repression effects of glucose on protease-production. this implies that it is a pleitropic gene in bacillus subtilis ki-2-132. the disruption of the gene caused morphological changes and repressed the expression of apre in vectors.19979361457
electrophysiology of optic nerve input to suprachiasmatic nucleus neurons in rats and degus.neurons in the mammalian suprachiasmatic nucleus (scn), the principal pacemaker of the circadian system, receive direct retinal input. some scn neurons respond to retinal illumination or optic nerve stimulation with changes in firing rates. in nocturnal rodents, retinal illumination increases firing rates of a large majority and decreases firing rates of a minority of responsive neurons. in two species of diurnal rodent, these proportions are altered or even reversed. since retinal input to the ...200312505666
relation of glucocorticosteroids and testosterone to the annual cycle of free-living degus in semiarid central chile.we investigated seasonal patterns of plasma glucocorticosteroids (gcs) in both sexes and testosterone (t) in males in relation to the annual cycle in central chile of a natural population of the degu (octodon degus), a caviomorph rodent. we wanted to find out which gcs are present in degus, whether their seasonal variation suggests suppressive or synergistic interrelationships with t, and whether seasonal variation in gc levels indicates a relationship with energy mobilization and demands of rep ...199910417237
differential emotional experience induces elevated spine densities on basal dendrites of pyramidal neurons in the anterior cingulate cortex of octodon appears likely that, in analogy to the synaptic development of sensory and motor cortices, which critically depends on sensory or motor stimulation (rosenzweig and bennett, 1996), the synaptic development of limbic cortical regions are modulated by early postnatal cognitive and emotional experiences. the very first postnatal experience, which takes place in a confined and stable familial environment, is the interaction of the newborn individual with the parents and siblings (gray, 1958). the ...200111457580
suprachiasmatic nucleus and intergeniculate leaflet in the diurnal rodent octodon degus: retinal projections and immunocytochemical characterization.the neural connections and neurotransmitter content of the suprachiasmatic nucleus and intergeniculate leaflet have been characterized thoroughly in only a few mammalian species, primarily nocturnal rodents. few data are available about the neural circadian timing system in diurnal mammals, particularly those for which the formal characteristics of circadian rhythms have been investigated. this paper describes the circadian timing system in the diurnal rodent octodon degus, a species that manife ...199910426502
isolation of cryptococcus neoformans in antwerp zoo's nocturnal house.cryptococcosis was diagnosed postmortem in a striped grass mouse (lemniscomys barbarus) housed in the nocturnal department of antwerp zoo. eight of the remaining mice in the cage were captured. cryptococcus neoformans was isolated from the lung of one animal. two mice had an elevated serum cryptococcal antigen titre. on examination of the pooled faecal samples collected from 17 animal species housed in 23 cages of the nocturnal department, the pathogenic yeast was isolated from the faeces of the ...200415310332
degu-p represses expression of the motility fla-che operon in bacillus subtilis.bacillus subtilis implements several adaptive strategies to cope with nutrient limitation experienced at the end of exponential growth. the degs-degu two-component system is part of the network involved in the regulation of postexponential responses, such as competence development, the production of exoenzymes, and motility. the degu32(hy) mutation extends the half-life of the phosphorylated form of degu (degu-p); this in turn increases the production of alkaline protease, levan-sucrase, and oth ...200415342569
dna microarray analysis of bacillus subtilis degu, coma and phop regulons: an approach to comprehensive analysis of b.subtilis two-component regulatory systems.we have analyzed the regulons of the bacillus subtilis two-component regulators degu, coma and phop by using whole genome dna microarrays. for these experiments we took the strategy that the response regulator genes were cloned downstream of an isopropyl-beta-d-thiogalactopyranoside-inducible promoter on a multicopy plasmid and expressed in disruptants of the cognate sensor kinase genes, degs, comp and phor, respectively. the feasibility of this experimental design to detect target genes was dem ...200111557812
characterization of degu, a response regulator in listeria monocytogenes, involved in regulation of motility and contributes to virulence.the degu (lmo2515) gene encodes a putative response regulator in the food-borne pathogen listeria monocytogenes. it has 63% amino acid identity to the degu response regulator of bacillus subtilis. we have characterized the degu gene product in l. monocytogenes egd by generation of a deletion mutant. the deltadegu mutant was found to be non-motile in motility plate assay and no flagellin was detected. the mutant was attenuated in challenge of mice. northern blot analysis suggested that the degu g ...200415522505
gametogenesis and nucleotypic effects in the tetraploid red vizcacha rat, tympanoctomys barrerae (rodentia, octodontidae).nucleotypic effects link dna content with nuclear size and cell dimensions of reproductive cells in polyploid organisms. we studied the gametogenesis of the allotetraploid rodent tympanoctomys barrerae, aiming to determine these effects in reproductive cells. the species' cofamily members, octodon degus and spalacopus cyanus were used as control. spermatogenesis and oogenesis in t. barrerae follows the pattern of differentiation and sequence of events of the control species, but varied nucleotyp ...200415586825
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