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A boxing method that uses irreversible hydrocolloid for boxing final impressions made with four different final impression materials was described. The boxing material separated from the impression in one piece with all impression materials. No separation media was required. In addition, the accuracy of the borders of all impression materials was equally well preserved.
Adult rats, previously subjected to bilateral frontal, parietal, occipital, frontocingulate or posterior cingulate ablations, were required to learn two discrete latch-box tasks (sliding a barrel-bolt to the right and elevating a hook). Those groups showing significant learning impairments had lesions to either the frontal cortex or frontocingulate cortex. The data suggest that the neocortical focus for latch-box deficits lies rostral to Level 8 on the Lashley brain diagram, while the frontocingulate focus for latch-box deficits lies within the prelimbic area.
Two experiments were carried out in order to 1) replicate a previous finding according to which the treatment on large platforms (commonly used as control for the stress induced by smaller paradoxical sleep deprivation platforms) can facilitate the acquisition and long-term retention (LTR) of a distributed shuttle-box avoidance in rats, and 2) further examine the temporal conditions in which that facilitation can be observed. The results showed that an immediate posttraining treatment lasting 6 hours induced a significant improvement of acquisition both when applied in the light (8 a.m.) and in the dark cycle (8 p.m.), while the LTR (10 and 31 days) seemed to be better preserved when the treatment was applied during the dark cycle. A shorter treatment (3 h) had no effect upon shuttle-box avoidance, regardless of whether it was applied in the dark or in the light cycle and whether it was immediate or delayed for 3 h. In summary, under certain temporal conditions, a posttraining immediate treatment on large platforms can facilitate the acquisition and/or the LTR of shuttle-box avoidance. Stress hormones and/or the enhancement of CNS arousal are suggested to be some of the mechanisms operating in this facilitatory effect.
The adenovirus E1A protein and immediately early (IE) protein of pseudorabies virus stimulate transcription from many promoters. It has been postulated that these proteins function via cellular intermediates. We analyzed the transcription of adenovirus E1B promoter mutants in response to the stimulatory effect of IE protein in comparison with E1A. Far upstream deletions and precise Sp1 and TATA box substitution mutations were examined. Only mutations affecting the TATA box element interfered with transactivation by IE protein. This result is similar to observations for E1A transactivation (L. Wu et al. Nature (London) 326, 512-515, 1987), suggesting that both E1A and IE proteins mediate transactivation of the E1B promoter through a common cellular intermediate which interacts with the TATA box.
The avian nuclear protein, enhancer factor 1 (EF1), binds specifically to the long terminal repeat (LTR) of Rous sarcoma virus (RSV) in a region that has been implicated in enhancer/promoter function. We have characterized the in vitro binding properties of this factor from chick embryo nuclear extracts by methylation interference/protection foot-printing of the wild-type LTR and also by gel electrophoretic mobility shift assays performed on a series of LTR mutants. We find that the inverted CCAAT pentanucleotide located at position -129 is essential for EF1 binding in vitro. Nucleotides flanking this element exert a smaller effect on binding. Linker-substitution and point mutations which reduce EF1 binding to this site in vitro also reduce promoter activity in transiently transfected cells. EF1 also binds with lower affinity to another inverted CCAAT box at position -65, an element which we show is also essential for transcriptional activity of the RSV LTR. We conclude, therefore, that EF1 is a CCAAT box-binding factor which is involved in the activation of RSV transcription in avian cells. Furthermore, we show that EF1 can recognize the CCAAT boxes of several other promoters in which the functional importance of this pentanucleotide has been established.
The validity of a black and white test box to measure changes in mouse exploratory behaviour relevant to assessment of anxiety was investigated by variation of the illumination within the test box, the use of different strains of mice, holding conditions and drug treatments. The suppression of exploratory activity in the white section caused by bright illumination was antagonised by anxiolytic agents from the benzodiazepine series, buspirone, 5-HT3 receptor antagonists, alcohol, nicotine, morphine and SCH23390. The anxiogenic agent FG7142 exacerbated the behavioural suppression. Black C57/BL/6, brown DBA2 and albino BKW mice were sensitive to the effects of drug treatments, whereas albino Tuck mice were less responsive. It is concluded that the characteristic change in mouse exploratory behaviour caused by anxiolytic agents is to preferentially increase exploratory behaviour in the white aversive section of the black and white test box. It is most consistently shown by (a) an increased time spent in the white section with proportional increases in (b) rearings and (c) ambulation and (d) a delay in the initial transition from the white to the black section.
We have introduced four point mutations into the 5' junction (GTATGT) and TACTAAC box of a yeast intron-containing gene coding for beta-galactosidase. To analyze quantitatively mutant combinations, we deliberately avoided nucleotides adjacent to the sites of cleavage (GTATGT) and lariat formation (TACTAAC) and chose positions with expected weak effects on splicing. All four mutants do not affect, or only marginally affect, gene expression. The levels of precursor RNA and intermediates indicate, however, that splicing efficiency is affected in all cases; the first stage of splicing, 5' cleavage and lariat formation, is reduced two to 15-fold in these four mutants. The mutants were combined to generate compensatory and noncompensatory double mutant combinations. No evidence for a specific base-pairing interaction between the 5' junction and TACTAAC box could be obtained. The results suggest that all conserved positions in the 5' junction and TACTAAC box play a role in splicing efficiency.
undulated (un) homozygous mice exhibit vertebral malformations along the entire rostro-caudal axis. Pax 1, a murine paired box-containing gene, is expressed in ventral sclerotome cells and later in intervertebral disks along the entire vertebral column. We localized the Pax 1 gene on chromosome 2 between beta 2-microglobulin and the agouti locus to an area where un maps. DNA analysis of the un mutant revealed a point mutation in a highly conserved part of the paired box of Pax 1, leading to a Gly-Ser replacement. The chromosomal location and the mutation in the paired box of un mice in conjunction with Pax 1 gene expression in wild-type mice implicate a causative role of Pax 1 in generation of the vertebral column.
Behavioural effects of somatostatin after intracerebroventricular (icv) administration have been investigated in male rats. In a passive avoidance learning test, somatostatin (1 microgram), given 30 min before the learning session, increased the avoidance latency at 24 h, but not at 48 h, after the injection, when compared to a 10 micrograms treated group. However, compared to a saline treated group, somatostatin (0.01, 0.1, 1, or 10 micrograms) did not significantly influence the avoidance latency. In a shuttle box experiment somatostatin (1 microgram) facilitated the learning process. In an open-field behaviour test, immediately after the 24 h passive avoidance test, 10 micrograms of the peptide decreased the rearing activity without influencing other open field behaviours, like locomotion, grooming and defecation. In a second open-field experiment somatostatin (1 microgram), given 30 min prior to the test, similarly as in the shuttle box learning experiment, increased the locomotion of the animals. These data suggest that somatostatin influences both the passive avoidance and shuttle box behaviours. The peptide-induced motor performance of the animals may play an important role in influencing the responses observed in these behavioural tests.
"The use of the Box-Jenkins approach for forecasting the population of the United States up to the year 2080 is discussed. It is shown that the Box-Jenkins approach is equivalent to a simple trend model when making long-range predictions for the United States. An investigation of forecasting accuracy indicates that the Box-Jenkins method produces population forecasts that are at least as reliable as those done with more traditional demographic methods."
1. The two-compartment black and white box first described by Crawley and Goodwin (1980) has been used to study anti-anxiety properties of drugs but has not been validated. 2. An automated test system and validation of the protocol for the evaluation of compounds with anxiolytic or anxiogenic potential is described. 3. The box is partitioned into black and white sections with an interconnecting opening and is equipped with micro-switch photoelectric controls (light source and photoreceiver) and an interface connected to the menu-driven computer during anxiety testing. 4. Plasma corticosterone levels in naive mice maintained on a reversed L:D cycle was significantly reduced following restricted exposure to the brightly lit white section but not in the red-illuminated black section. 5. The optimal structural configuration in different test situations was found to be a square rather than a round box. 6. Under normal conditions, mice spend about 60% of the time in the dark compartment so that the exploratory activities and time spent in the white section are taken as a measure of anxiety. 7. Compounds examined included the reference anxiolytic diazepam, nicotine, naloxone, MDL 72222, ICS 205 930 and buspirone, all of which increased mouse exploratory activities in the white section. PTZ, beta-CCP, morphine and amphetamine increased exploration in the black compartment and reduced exploration in the white area. 8. Fluphenazine and imipramine had no specific effects on anxiety responding, although the cataleptogenic effect of fluphenazine was apparent. 9. Daily repeated testing was possible with a maximum of up to four trials a week using naive animals during the 5-min test session. 10. The results suggest that the rapid and automated test system for the assessment of changes in measures of anxiety is not only valid for large scale evaluation of compounds but could be used to elucidate mechanisms of drug action and the CNS pathways linked with anxiolysis and/or anxiogenesis.
The product of the sex-determining gene SRY is a member of the HMG box containing protein superfamily. The HMG box is a DNA-binding domain of about 80 amino acids shared by many proteins with diverse functions. It seems that the functions of the full length protein are restricted to the HMG box but their molecular basis remains to be determined. We have summarized here the properties of this binding domain described so far in the literature and, using a synthetic peptide mimicking the DNA binding domain (SRY80), we have confirmed the existence of DNA minor groove contacts with this domain. Using intrinsic fluorescence of the tryptophane, the interaction between SRY80 and the putative target sequence AACAAAT was also quantified. In conclusion, we also consider the possible putative action of SRY to fulfill its role in sex determination.
The relationship between the learning ability of normal rats and the facility to induce long-term potentiation (LTP) in the same animals was investigated. Behavioral performance was measured in a shuttle box avoidance paradigm, using a buzzer as conditioned stimulus. Three days later animals were sacrificed; frequency threshold necessary to induce LTP was determined in transverse hippocampal slices taken from these animals and maintained in vitro. A linear regression analysis on the behavioral and electrophysiological data showed a negative correlation (Spearman rank correlation coefficient rs = -0.705; P less than 0.001) between percent of conditioned responses in the shuttle box and threshold frequency necessary to induce LTP in gyrus dentatus in response to tetanic stimulation of the perforant path. It is concluded that learning ability of normal rats in a shuttle box avoidance paradigm is correlated with hippocampal synaptic plasticity.
Genes clockwise of oriC, the Escherichia coli replication origin (oriC-mioC-asnC), show anticlockwise transcription. The intergenic region between mioC and asnC contains both a terminator and a consensus DnaA-protein-binding site (dnaA box). We analysed termination in this region using galK expression to monitor for transcription. About 50% of the asnC transcripts were not terminated, and about 25% terminated at the asnC terminator. We found that the DnaA protein/dnaA box complex acts as a terminator of transcription for about 25% of the transcripts. Its efficiency could be increased by raising the level of DnaA protein, or it could be inactivated by deletion in the dnaA box or by thermal denaturation of the DnaA protein.
The functional interaction between the human epsilon globin promoter and an erythroid-specific transcription enhancer, 5' HS-2, has been analyzed by transient expression assay. While stepwise deletion of DNA sequences between -852 and -122 had only small effects, removal of the CACC box at position -111 greatly decreased epsilon-globin promoter activity, as well as its response to the enhancer function of 5' HS-2 in erythroid cells. Our data demonstrated that the three ubiquitous promoter elements, the CACC, CCAAT, and TATA boxes, of the epsilon-globin-encoding gene together form a minimal promoter that would interact efficiently with 5' HS-2, and that at least the CACC box is an essential functional component of this enhancer-promoter interaction.
There are two SOS box-like sequences located at the regions -161 to -142 and -69 to -50 with regard to the initiation codon of phr. Ihara et al. (1987) constructed a phr'-'lacZ fusion plasmid in which these sequences and the amino terminal end of the phr gene was fused to lacZ and therefore lacZ was under the regulatory control of phr promoter-operator. The authors found that in cells carrying this plasmid beta-galactosidase was inducible by UV and UV-mimetic agents and concluded that phr was controlled by the LexA repressor. We wished to confirm these results by theoretical analysis of the SOS-like sequences by the method developed by Berg (1987) as well as by measuring the binding of LexA protein to the putative SOS boxes by a novel gel retardation assay. Both theoretical analysis and experimental results indicate that the putative SOS boxes immediately 5' to phr have no specific affinity for LexA protein.
A fast and reliable method for bovine sexing has been developed through amplification of the bovine high motility group (HMG) box of the sex-determining region of the Y chromosome gene (SRY). Oligonucleotide primers were designed according to the conserved bovine SRY HMG box sequence motif. In agarose gel electrophoresis, a normal bull showed 1 SRY band, and a normal cow showed no SRY band. After optimization, the PCR procedure for sex determination was applied to 14 embryo biopsies. The biopsied embryos were transferred into 14 recipient cows on the same day (day 7 of the estrus cycle) that the embryos were collected and sex of the calf was confirmed after parturition. Nine calves were born and anatomical sex corresponded to those sex determined by PCR in all cases (100% accuracy). Thus, this study showed for the first time that the present method can be applied in bovine breeding programs to facilitate manipulation of the sex ratio of offspring and also allows a quick diagnosis for the XY-bovine offspring by amplification of the HMG box of the bovine SRY gene.
This study investigated sex differences in spatial memory using a human analogue of the Radial Arm Maze: a revision on the Nine Box Maze originally developed by called the 17-Box Maze Test herein. The task encourages allocentric spatial processing, dissociates object from spatial memory, and incorporates a within-participants design to provide measures of location and object, working and reference memory. Healthy adult males and females (26 per group) were administered the 17-Box Maze Test, as well as mental rotation and a verbal IQ test. Females made significantly fewer errors on this task than males. However, post hoc analysis revealed that the significant sex difference was specific to object, rather than location, memory measures. These were medium to large effect sizes. The findings raise the issue of task- and component-specific sexual dimorphism in cognitive mapping.