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At least 19 recordsLinked to original sources
PubMed1976

Comparison of unilateral dominant and non-dominant ECT on verbal and non-verbal memory.

An intraindividual, double-blind cross-over comparison of the effects of dominant (D) and non-dominant (ND) temporo-parietal unilateral electroconvulsive therapy (ECT) was performed in connection with the second and third treatment, the type of electrode placement being allocated at random. Four memory tests were used. The 30 Word-Pair Test is an audio-visual verbal recall test, the 30 Figure Test is a mainly visual recognition test with easily verbalized items. The 30 Geometrical Figure Test and the 30 Face Test are nonverbal recognition tests of visual complex and unfamiliar material. Compared with dominant ECT, non-dominant ECT has a more negative influence in the complex non-verbal visual tests, whereas dominant ECT has a more negative effect on verbal memory. In the non-verbal tests, as compared with the verbal ones, the encoding (or learning) is relatively more influenced and the retention (or storage) relatively less. An impairment either of complex apperceptive function or of memory may be responsible for the relatively lower performance in non-verbal tests after non-dominant ECT.

Adult↗
PubMed1976

R factor-mediated tetracycline resistance in Escherichia coli K12. Dominance of some tetracycline sensitive mutants and relief of dominance by deletion.

Strains of Escherichia coli K12 heterozygous for the R100-1 tetracycline resistance region were constructed. They carried the wild-type Tetr genes in the chromosome and single site Tets mutations on plasmids. Some heterozygotes could not express tetracycline resistance fully after induction. The mutant tet allele was thus partially dominant. When heterozygotes carrying the dominant tet mutant were plated on agar containing 20 mg/ml tetracycline, mutants which grew normally occurred at a frequency of 1-4 X 10(-4). Analysis of these dominance relief mutants showed that in 53/56 isolates the dominant tet allele was lost forming either Tra+ or Tra- deletion mutants of the plasmid. The mutation frequency was not affected either by the host chromosomal recA mutation or by the temperature of growth of the culture.

Chromosome Deletion↗
PubMed1975

Studies on chemically induced dominant lethality. I. The cytogenetic basis of MMS-induced dominant lethality in post-meiotic male germ cells.

Young adult male mice were injected intravenously with doses of methyl methanesulfonate(MMS) ranging from 25 to 100 mg/kg body weight. These males were serially mated to superovulated females from day 1 post injection to day 23 post injection. The morning after mating (about 4-6 h post-copulation) the females were sacrificed and ova flushed from the ampulla. The ova were cultured, in the presence of colchicine, for 26 h and metaphase preparations made of the first cleavage division. Chromosome analysis was done and the types, and extent, of chromosome aberrations correlated to previously published dominant lethal data at the same MMS doses and time intervals. The types of aberrations seen were predominantly double fragments (presumably isochromatid deletions), chromatid interchanges, and some chromatid deletions, as well as shattering effect on the male complement at the highest dose and the time of peak sensitivity to dominant lethal induction. When the frequency of cells containing a cytologically visible aberration is compared to the total dominant lethal data an excellent correlation is obtained. Furthermore, the frequency of highly damaged cells, agrees very well with estimated frequencies of preimplantation loss. These data strongly suggest that chromosome aberrations seen at the first cleavage stage are the basis of MMS-induced dominant lethality.

Animals↗
PubMed1976

Studies on chemically induced dominant lethality. II. Cytogenetic studies of MMS-induced dominant lethality in maturing dictyate mouse oocytes.

Young adult female mice were injected intravenously with either 50- or 100- mg/kg doses of methyl methanesulfonate. The females were superovulated and mated to untreated males at intervals ranging from 0.5 to 14.5 days after treatment. The fertilized ova were collected and cultured to the first cleavage mitosis, at which time the female chromosome complement was analyzed for structural chromosomal damage. Chromatid-type aberrations were observed, but at a much lower frequency than previously reported for treatment of post-meiotic male germ cells. The time after treatment at which chromosomal damage was observed and the frequency of affected cells agree, qualitatively, with existing dominant-lethal data derived from treatment of maturing oocytes. Parallel experiments in which metaphase I oocytes were analyzed indicate a lack of MMS-induced chromosomal damage in the meiotic stages. This observation is consistent with the suggestion that an intervening round of DNA synthesis is necessary for MMS-induced lesions to be translated into chromosomal damage. The low yield of chromosomal damage is consistent with the idea that maturing oocytes, unlike later spermatids and spermatozoa, are capable of performing macromolecular repair of premutational lesions.

Animals↗
PubMed1977

Frequency and significance of coronary arterial dominance in isolated aortic stenosis.

Myocardial infarction during aortic valve replacement has previously been reported to result from obstruction of a branch of the left main coronary artery by the perfusion cannula. Patients with a dominant left coronary arterial system may be at greater risk. To assess the frequency and significance of a dominant left coronary arterial system the coronary angiograms of 75 consecutive patients more than 34 years of age with isolated aortic stenosis were studied and compared with those of a control group of 150 patients. Among the patients with aortic stenosis, 19 (25 percent) had left dominance, 9 (12 percent) a balanced circulation and 47 (63 percent) a dominant right coronary arterial system. Among control patients, 14 (9 percent) had left dominance 18 (12 percent) a balanced system and 118 (79 percent) right dominance. The increased prevalence of left dominance in patients with aortic stenosis was significant (P less than 0.005). Among patients with aortic stenosis, the left main coronary artery was shorter (P less than 0.01) in those with left dominance (6.2 +/- 1.3 mm [mean +/- standard error]) than in those with right dominance (9.9 +/- 0.7). Sixty-nine patients with aortic stenosis underwent aortic valve replacement. Perioperative myocardial infarction occurred in 4 of 15 (26.7 percent) of those with left dominance and in 4 of 54 (7.4 percent) of those with right dominance or a balanced circulation (P less than 0.05). Perioperative myocardial infarction occurred in all three patients with left dominance and obstructive coronary artery disease. The increased prevalence of a dominant left coronary arterial system in aortic stenosis suggests that this may be part of a developmental complex. Patients with left dominance have a shorter left main coronary artery than patients with right dominance. They also have an increased risk of perioperative myocardial infarction if there is associated obstructive coronary artery disease. Preoperative information about the coronary arterial anatomy and extent of coronary artery disease may be helpful in planning the use of coronary perfusion and other myocardial preservation techniques during surgery in order to reduce the incidence of myocardial infarction.

Aortic Valve Stenosis↗
PubMed1978

Association of left dominant coronary arterial system with congenital bicuspid aortic valve.

Clinical angiographic studies have documented an association of left dominance of the coronary arteries with aortic stenosis and congenital bicuspid aortic valve. The postmortem arteriograms of 973 autopsy patients were reviewed for pattern of coronary dominance and the hearts examined for the nature of any aortic valve disease. There were 673 hearts (70 percent) with a right dominant pattern, 198 (20 percent) with equal dominance and 102 (10 percent) with left dominance. Of 34 hearts with congenital bicuspid aortic valve, 10 (29 percent) had left dominance, a difference significant at the 0.005 level. Of 44 hearts with calcific aortic stenosis, an acquired valve lesion, 9 (20 percent) had left dominance. Rheumatic aortic valve disease (47 cases) and aortic regurgitation (27 cases) had no apparent relation to the coronary arterial pattern. The results confirm the association of left coronary arterial dominance with congenital bicuspid aortic valve. It is suggested that a left dominant coronary system may arise as a consequence of disproportionately decreased blood flow in the left heart chambers, one cause of which is aortic valve stenosis, during early cardiogenesis.

Adolescent↗
PubMed2025

A Balanced Inversion Polymorphism Exhibits a Dominance Reversal at the Gene Expression Level that Depends on Developmental Context.

How genetic variance for fitness is maintained is incompletely understood. Mutation-selection balance and single-locus overdominance cannot account for the large variance observed. Recent work suggests that antagonistic balancing selection, favoring different alleles in different contexts and involving beneficial dominance reversals, might contribute to maintaining fitness variance. However, while this mechanism is plausible, evidence for dominance reversals remains scarce. Here, we study how In(3R)Payne, a balanced inversion polymorphism in Drosophila melanogaster, affects gene expression and chromatin accessibility by using RNA-seq and ATAC-seq (assay for transposase-accessible chromatin with sequencing). We find that, in embryos, the inverted (INV) arrangement tends to have dominant effects, while the standard (STD) arrangement behaves like a recessive Mendelian allele. Yet, in wing discs, this pattern is reversed: STD has mostly dominant effects, whereas INV behaves recessively. Since this shift in the dominance of the INV "allele" between developmental contexts affects the expression of suites of genes in a concerted manner, it might be mediated by a dominance modifier, for example, a transcription factor. In favor of this idea, 25% of the differentially expressed genes between INV and STD encode transcription factors. Interestingly, while only four differentially expressed genes are shared between embryos and wing discs, one of them is HP1c, a chromatin-binding protein and major transcriptional regulator, and thus a promising candidate for mediating the context-dependent change in dominance. Although the relationship between these patterns and fitness is presently unknown, our observations are consistent with a potential role of reversals (or, more generally, shifts) of dominance in maintaining inversion polymorphism.

Animals↗
PubMed2026

Sex differences in social dominance emerge late in life in a gregarious bird.

Social dominance shapes group structure and the collective behaviour of gregarious animals. Senescence, the progressive physiological deterioration associated with ageing, may influence behaviour, including social dominance, while reproductive roles may lead to different onset times or rates of senescence between the sexes. However, how ageing shapes sex differences in sociality remains poorly understood, largely due to the scarcity of long-term studies comparing male and female social behaviour. To address this gap of knowledge, we monitored dominance hierarchies during foraging in an ageing, semi-natural population of adult common waxbills (Estrilda astrild). Our study lasted 5 years, which is more than most adult waxbills would live in the wild, to facilitate detecting effects of senescence. At the onset of the study, sex differences in dominance were negligible but became pronounced with ageing during breeding seasons. In contrast, sex differences remained weak during non-breeding seasons. Females showed stronger longitudinal and seasonal changes in dominance than males, whose dominance patterns remained more consistent across breeding and non-breeding periods. Nonetheless, social dominance also increased, on average, as the number of years until death decreased. Although sex differences in animal sociality are often thought of as largely fixed, our findings reveal a dynamic pattern in which sex differences in dominance emerge with ageing and are context-dependent, varying across breeding seasons. Overall, our results suggest that senescence and seasonal context shape sociality later in life.

behavioural ageing↗
PubMed1977

Handedness in relation to direction and degree of cerebral dominance for language.

In so far as ear asymmetries on dichotic listening reflect cerebral dominance for language, the present evidence indicates a progressively decreasing incidence of left hemisphere dominance in right handed, mixed handed and left handed individuals. In the absence of a family history of sinistrality there are no indications that the degree of dominance is reduced in left handers or mixed handers when compared to right handers, nor that right hemisphere dominance is less securely established than left hemisphere dominance. Among strong left handers with a family history of sinistrality, however, ear difference scores are significantly smaller, indicating reduced lateralization or bilateral representation of language in such individudals. This applies equally in left dominant and right dominant left handers.

Adolescent↗
PubMed1978

Ocular dominance in layer IV of the cat's visual cortex and the effects of monocular deprivation.

1. The relation between the physiological pattern of ocular dominance and the anatomical distribution of geniculocortical afferents serving each eye was studied in layer IV of the primary visual cortex of normal and monocularly deprived cats. 2. One eye was injected with radioactive label. After allowing sufficient time for transeuronal transport, micro-electrode recordings were made, and the geniculocoritcal afferents serving the injected eye were located autoradiographically. 3. In layer IV of normal cats, cell were clustered according to eye preference, and fewer cells were binocularly driven than in other layers. Points of transition between groups of cells dominated by one eye and those dominated by the other were marked with electrolytic lesions. A good correspondence was found between the location of cells dominated by the injected eye and the patches of radioactively labelled geniculocortical afferents. 4. Following prolonged early monocular deprivation, the patches of geniculocortical afferents in layer IV serving the deprived eye were smaller, and those serving the non-deprived eye larger, than normal. Again there was a coincidence between the patches of radioactively labelled afferents and the location of cells dominated by the injected eye. 5. The deprived eye was found to dominate a substantial fraction (22%) of cortical cells in the fourth layer. In other cortical layers, only 7% of the cells were dominated by the deprived eye. 6. These findings suggest that the thalamocortical projection is physically rearranged as a consequence of monocular deprivation, as has been demonstrated for layer IVc of the monkey's visual cortex (Hubel, Wiesel & Le Vay, 1977).

Animals↗
PubMed1978

[High tone audiometry I. Dominant sidedness of hearing (author's transl)].

Tests for determining the dominant hearing ear by use of high tone audiometry (18 to 16 KHz) on 100 male and female "normal hearing" patients aged between 5 and 71 years of age demonstrated a relationship with whole body laterality (eye dominance, preferred tongue side, vocal cord asymmetry and hand and foot dominance). Right ear dominance was found in 62 of 85 right-handed individuals, whereas left ear dominance was found in only 3 of 10 left-handed individuals. In 5 with ambidexterity high tone audiometry failed to show any significant preference. High tone audiometry clearly clarifies cerebral hemisphere dominance and this auditory dominance can be utilized therapeutically as well as prognostically.

Audiometry↗
PubMed2025

CRISPR/Cas9-compatible plasmids enabling seven dominant genetic selection methods for the human fungal pathogen Cryptococcus neoformans.

Cryptococcus neoformans is the most common cause of human fungal meningitis and an important model system for studying fundamental eukaryotic biology. Genetic manipulation of this organism relies on three dominant drug resistance markers (nourseothricin acetyltransferase [NAT], neomycin phosphotransferase II [NEO], and hygromycin B phosphotransferase [HYG]) and the recyclable dominant prototrophic marker amdS. With ongoing technological advances that are expanding our ability to explore cryptococcal gene function, contemporary studies often require multiple genetic manipulations in the same strain. Additional dominant selection methods would maximize the utility of these tools by facilitating their combinatorial use. Here, we identify blasticidin S resistance via the blasticidin S deaminase (BSD) or blasticidin S resistance (BSR) markers as a novel dominant selection method for C. neoformans. We further validate phleomycin resistance via the bleomycin resistance gene (BLE) marker as an additional selection method, confirming a study that first established this marker 25 years ago (J. Hua, J. D. Meyer, and J. K. Lodge, Clin Diagn Lab Immunol 7:125-128, 2000, https://doi.org/10.1128/cdli.7.1.125-128.2000). To enable highly efficient CRISPR/Cas9-mediated genome modification, we incorporated these markers, as well as the newly established dominant prototrophic marker ptxD (M. Khongthongdam, T. Phetruen, and S. Chanarat, Microbiol Spectr 13:e01618-24, 2025, https://doi.org/10.1128/spectrum.01618-24), into a vector series that enables the construction of fused marker-sgRNA products via PCR. Altogether, this work expands the number of dominant genetic selection methods for C. neoformans to seven, including five drug selection regimes and two prototrophic methods. The vector series has been deposited at Addgene. IMPORTANCE Cryptococcus neoformans is the top-ranked World Health Organization priority fungal pathogen due to its widespread distribution and inadequate treatment options. Additionally, as a basidiomycete yeast occupying an underexplored branch of the fungal kingdom, this organism is a powerful system for deciphering core eukaryotic biology that is absent in classic model fungi. Defining functions for novel cryptococcal genes is a crucial priority, and the availability of additional genetic selection methods would facilitate these efforts. In this study, we establish blasticidin S resistance as a novel genetic selection method for C. neoformans, and we validate a previous report using phleomycin resistance as such. This work expands the number of reliable dominant selection methods to seven, providing flexibility for the introduction of sequential genetic modifications into single strains.

Cryptococcus neoformans↗
PubMed1977

Dominant lethal mutations in male mice.

Dominant lethal mutations are due to chromosome aberrations as demonstrated by analysis of first cleavage. With a sample size of 40-45 mice per dose the induction of dominant lethal mutations by 10 mg/kg of methyl methanesulfonat (MMS) can be detected in spermatids in the mating interval 9-12 days posttreatment (6-11%). In the same mating interval a dose of 150 mg/kg of MMS induces 100% dominant lethal mutations. MMS and other chemical mutagens can be characterized by their different spermatogenic response. The germ cell stage specific induction of dominant lethal mutations by chemical agents is very likely due to their different pathways and therefore, to different effects on the structural and macromolecular changes during spermatogenesis. The feasibility of standardizing test protocol for the dominant lethal assay in mice, based on collaborative studies, is discussed. The reproducibility of results and the sensitivity of the induction of dominant lethal mutations in the collaborative studies demonstrate the usefullness of the method for mutagenicity screening.

Animals↗
PubMed1977

Anterior shift of the dominant EEG rhytham during anesthesia in the Java monkey: correlation with anesthetic potency.

EEG amplitude dominance in awake man is posterior. During EEG monitoring in patients, the authors observed the abrupt appearance of anterior amplitude dominance during induction of anesthesia with halothane, enflurane, or thiopental. This EEG change is coincident with loss of eyelid reflex and loss of ability to respond to command. This EEG change was studied with several anesthetics in five Java monkeys to determine alveolar anesthetic concentration at which it occurred and to observe the effects of various stimuli on it. EEG recordings were obtained after equilibration at each level with increasing concentrations of halothane, enflurane or isoflurane in oxygen and each agent again in 30 per cent N2O, in separate experiments in the same animals. EEG amplitude dominance became anterior in each animal with each anesthetic and combination at concentrations less than MAC, which was also determined in the same experiments. At lower concentrations, stimulation at equilibrated anesthetic concentrations resulted in abrupt EEG return to posterior amplitude dominance. The end-tidal anesthetic concentration at which persistence of anterior EEG dominance was seen after stimulation was approximately 0.4 MAC for each anesthetic and combination tested. This is interpreted as support for physical solution-lipid solubility theories of anesthetic action. In addition, an EEG change common to various anesthetics may increase the clinical usefulness of EEG monitoring. It is speculated that this EEG change may signal loss of awareness. If so, observance of sustained anterior EEG amplitude dominance may provide assurance of obliteration of awareness during anesthesia.

Anesthetics↗