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PubMed1989

Gordon Memorial Lecture. The genetic-behavior interface and well-being of poultry.

Marked changes have occurred in poultry production practices and in stocks bred for the production of meat and eggs. Of behavior pattern that originally favoured domestication, positive responses to humans and adaptability to environments are now most important. Development of specific strains for production of meat or eggs resulted in correlated responses in behavioural traits. Compared with egg strains, meat strains are docile and have excessive appetites, poor immunoresponsiveness and reduced motor ability. Genotype by environment interactions for behaviour limit inferences concerning responses of stocks across environments. Innate behaviour patterns and habituation processes can prevent some stimuli from causing physiological manifestations observed in general responses to stressors. Husbandry procedures should optimise phenotypic expressions of genetic potential to enhance well-being.

Adaptation, Physiological↗
PubMed1986

Immunoblotting: an emerging technique in immunohematology.

Protein blotting is a technique of transferring and immobilizing the original protein patterns from gel matrices to a suitable solid phase. It can be employed in identifying the protein antigens in complex biological mixtures, since each protein is accessible to its corresponding antibody. This method, called immunoblotting, is also applicable to define the specificity of a given antibody. The perspective of immunoblotting has already found wide application in basic research. Some features of the immunoblotting and recent improvements of the original procedures will be discussed. To justify a wider application in clinical research I will summarize some applications with respect to immunohematology.

Antibody Specificity↗
PubMed2003

Kv3 potassium conductance is necessary and kinetically optimized for high-frequency action potential generation in hippocampal interneurons.

Kv3 channels are thought to be essential for the fast-spiking (FS) phenotype in GABAergic interneurons, but how these channels confer the ability to generate action potentials (APs) at high frequency is unknown. To address this question, we developed a fast dynamic-clamp system (approximately 50 kHz) that allowed us to add a Kv3 model conductance to CA1 oriens alveus (OA) interneurons in hippocampal slices. Selective pharmacological block of Kv3 channels by 0.3 mm 4-aminopyridine or 1 mm tetraethylammonium ions led to a marked broadening of APs during trains of short stimuli and a reduction in AP frequency during 1 sec stimuli. The addition of artificial Kv3 conductance restored the original AP pattern. Subtraction of Kv3 conductance by dynamic clamp mimicked the effects of the blockers. Application of artificial Kv3 conductance also led to FS in OA interneurons after complete K+ channel block and even induced FS in hippocampal pyramidal neurons in the absence of blockers. Adding artificial Kv3 conductance with altered deactivation kinetics revealed a nonmonotonic relationship between mean AP frequency and deactivation rate, with a maximum slightly above the original value. Insertion of artificial Kv3 conductance with either lowered activation threshold or inactivation also led to a reduction in the mean AP frequency. However, the mechanisms were distinct. Shifting the activation threshold induced adaptation, whereas adding inactivation caused frequency-dependent AP broadening. In conclusion, Kv3 channels are necessary for the FS phenotype of OA interneurons, and several of their gating properties appear to be optimized for high-frequency repetitive activity.

Action Potentials↗
PubMed1982

Monophasic and diphasic patterns of the circadian caecotrophy rhythm of rabbits.

The circadian caecotrophy rhythm was synchronized with the light-dark cycle of 12 : 12 h. During this the rabbits practised caecotrophy regularly during the light period. While most rabbits manifested 1 caecotrophy per 24 h (monophasic caecotrophy), some had an additional caecotrophy during the dark period (diphasic caecotrophy). During continuous light the circadian caecotrophy rhythm ran free monophasically, even in those rabbits which were diphasic under the preceding 12 : 12 regime. The average period length amounted to 24.7 +/- 0.3 h. Following restoration of the 12 : 12 routine animals reestablished their original caecotrophy pattern. In a further test the caecotrophy pattern remained constant during a constant 12 : 12 regime, but changed in 7 of 16 animals when the photoperiod was reduced first to 60 min and then to 2 x 60 min light every 24 h. The reduction of the lit time resulted in an increased occurrence of diphasic animals. Details of synchronization of the caecotrophy rhythm with the different light-dark schedules are given. These results accord with data obtained in nocturnal rodent species.

Age Factors↗
PubMed1996

Low dimensional attractors in discharges of sensory neurons of the rat spinal dorsal horn are maintained by supraspinal descending systems.

Background activity was recorded from sensory neurons in laminae I-V of the lumbar spinal dorsal horn of the rat prior to and during cold block spinalization at the cervical cord. To graphically and quantitatively describe the complexity of the discharge patterns, phase space portraits were plotted and the correlation dimension D2 was calculated by using the Grassberger-Procaccia algorithm adopted for point processes, i.e. for series of interspike intervals. The algorithm is validated both for the Baker transformation, which is a simple point process, and for the Lorenz model, whereby a transformation from continuous to point process variables is achieved. A method of surrogate data is provided in order to show the difference between original neuronal patterns and their surrogate stochastic data. Therefore, this method shows that neuronal discharge patterns cannot be fully described in terms of interspike interval histograms. However, in the intact cord most (73%) of the neurons displayed background activity with low (0.28-4.3) D2 values. During spinalization, D2 values significantly increased in 68% of the neurons showing previously low D2 values, irrespective of classification and laminar location of neurons, thus proving that tonic descending systems may maintain a high order in the discharge of sensory dorsal horn neurons.

Animals↗
PubMed1984

Mosaic pattern changes in human corneal endothelium with age.

The central corneal endothelium of 73 intact eyes was examined using a specular microscope. The photographs obtained were analyzed with a computerized digitizer for determination of the shape and size of the individual cells. The endothelium of cases younger than 30 years of age was composed mainly of hexagonal cells, 70% of all cells. With increasing age, however, the proportion as well as the number of hexagonal cells decreased significantly, although they continued to constitute the majority, 58%, of cells in the endothelium of cases over 70 years of age. There was a positive correlation between age and the proportion of nonhexagonal cells. It appears that the original hexagonal pattern of endothelial morphology is gradually lost with age, concurrent with a gradual increase in both mean cell size and variation in cell size.

Adolescent↗
PubMed2002

RecA and glnA sequences separate the bacteroides fragilis population into two genetic divisions associated with the antibiotic resistance genotypes cepA and cfiA.

The sequences of part of the glutamine synthetase-encoding gene (glnA) and of the RecA-encoding gene (recA) were determined and aligned for 45 Bacteroides fragilis isolates from different clinical and geographical origin. The patterns of sequence divergence of glnA and recA were very similar. The sequences of a 303-bp fraction of recA showed 45 nucleotide substitutions, 40 of which allowed the separation of B. fragilis into two major divisions, which were not found when the deduced amino acid sequences were considered. The 687-bp sequences analysed for the glnA gene showed 112 nucleotide substitutions, 96 of which separated the population into the same two divisions as those described for recA. In this case, the deduced amino acid sequences showed this subdivision as well: three of the six observed amino acid substitutions were division-specific. Within the two divisions, both genes presented a high degree of sequence conservation. Each B. fragilis division was associated with the presence of a different antibiotic resistance gene: cepA encoding a serine-beta-lactamase (division I) and cfiA encoding a metallo-beta-lactamase (division II). No particular clusters associated with geographical or clinical origin, or with the production of an enterotoxin were observed. Sequencing of the cfiA gene allowed identification of two different alleles in division II. However, no association of these different cfiA alleles with the expression of imipenem resistance was observed. In conclusion, the phylogenetic patterns observed by sequencing recA and glnA are in agreement with those obtained previously by MLEE (multilocus enzyme electrophoresis). Thus, it appears that the evolution of recA and glnA genes is similar to that of the whole chromosome of B. fragilis. Horizontal gene transfer between divisions I and II seems to be low, at best. However, the results of the present study could not clarify definitively whether divisions I and II should be considered as two different B. fragilis genospecies.

Bacterial Proteins↗
PubMed1992

Expression pattern of mouse mammary tumor virus in transgenic mice carrying exogenous proviruses of different origins.

To study the tissue specificity of mouse mammary tumor virus (MMTV) gene expression, we developed two series of transgenic mice, containing the MMTV proviral DNA of mammary (GR) and kidney (C3H-K) origin. The expression pattern in the MMTV(GR) transgenic mice is very similar to that observed in infected animals, e.g., a strong preference for viral expression in the lactating mammary glands and lower levels of expression in salivary glands, lymphoid tissues, and male reproductive organs. One line of transgenic mice carrying the C3H-K provirus has a similar expression pattern, indicating that MMTV(C3H-K), despite a striking alteration in the U3 region of its long terminal repeat, can be expressed in the same tissues as the wild-type MMTV.

Animals↗
PubMed1993

[Nuclear DNA content in breast carcinoma by fine needle aspiration biopsy].

The usefulness of the measurement of nuclear DNA content by fine needle aspiration biopsy was evaluated through a comparative study of fine needle aspirated and tissue samples. Nuclear DNA content was measured in patients with 28 primary and 2 metastatic lesions of breast carcinoma using fluorescent cytophotometry with Feulgen stain. The rate of correspondence on DNA ploidy pattern of aspirates and tissue samples was 86.7%. There was a significant correlation with DNA index (DI) (R = 0.85, p < 0.001) and S-phase fraction (%S) (R = 0.79, p < 0.001). The rate of correspondence of DI subgroups (3 aneuploid subgroups and diploid) was 80.8%. No tumor size affected values of DI and %S of aspirates. However, %S of papillotubular carcinoma showed small difference compared with values of tissue samples. Nuclear DNA content of fine needle aspirated samples had a significant correlation with that of tissue samples, providing the estimation of the original ploidy pattern and DI. Fine needle aspiration biopsy is an easy technique and able to be carried out repeatedly. Thus, the measurement of nuclear DNA content using aspirates is useful for broad practical purposes.

Adenocarcinoma↗
PubMed1977

The path and rate of growth of regenerating motor neurons in the cockroach.

Nerve root 5 that supplies the coxal depressor muscles from the metathoracic ganglion in the cockroach was crushed. Regeneration of the motor neurons was studied by cutting the nerve at several distances from the crush point and introducing cobalt chloride into the cut end. The operation was followed by a lag period of about 13 days after which the axons regenerated at a rate of 0.9 mm per day. After regeneration had been completed a pattern of axon distribution was established among the nerve branches that was very similar to that found in intact, normal cockroaches. This pattern was established through an apparent directed growth of certain axons from identified cells into branch 5rl, their normal pathway. However, at the same time, radom or increased branching of other unidentified motor neurons produced some errors in the distribution of axons among the nerve branches. Eventually these errors were corrected by the degeneration of neuronal processes that did not synapse with correct target muscles. These results demonstrate the requirement for a highly specific intercellular recognition process between individual, identified motor neurons and the appropriate muscles they innervate in order to reform the original innervation pattern during regneration.

Animals↗
PubMed1972

Tract specificity in the structure of down feathers of the newly-hatched chick.

Comparative study of completed down feathers from seven of the major tracts of newly-hatched Silver Campine chicks reveals tract-specific differences in the total length of the primary group of barbs and in the length of their barbule-free tips. Two classes of barbs can be distinguished on the basis of overall length in feathers of any one of the tracts: (a) those barbs that form from the first group (complement) of 9-11 barb ridges that arise in strict dorsoventral order around the circumference of the epidermal cylinder strict dorsoventral order around the circumference of the epidermal cylinder of the feather germ, and (b) those barbs that are added secondarily, later, either by the formation of a newly organized ridge between the bases of two of the original group of barb ridges, or by the splitting of one or more of the original complement of barb ridges. The primary (majority) group of ridges, only, are of use in gauging tract specificity. The statistical significance of measurements of total barb-length and the length of the barbule-free tips have been evaluated; differences between the feathers of each of the seven tracts examined can be distinguished statistically. The fact that the first feathers to form from the papillae are tract-specific shows, unquestionably, that specificity is present in the papillae from the very beginning of their organization, as might be inferred from their orderly pattern of origin in time and space within each of the various tracts.

Animals↗
PubMed1992

Purification of three cytotoxic lymphocyte granule serine proteases that induce apoptosis through distinct substrate and target cell interactions.

We recently reported the purification of a lymphocyte granule protein called "fragmentin," which was identified as a serine protease with the ability to induce oligonucleosomal DNA fragmentation and apoptosis (Shi, L., R. P. Kraut, R. Aebersold, and A. H. Greenberg. 1992. J. Exp. Med. 175:553). We have now purified two additional proteases with fragmentin activity from lymphocyte granules. The three proteases are of two types; one has the unusual ability to cleave a tripeptide thiobenzyl ester substrate after aspartic acid, similar to murine cytotoxic cell protease I/granzyme B, while two are tryptase-like, preferentially hydrolyzing after arginine, and bear some homology to human T cell granule tryptases, granzyme 3, and Hanukah factor/granzyme A. Using tripeptide chloromethyl ketones, the pattern of inhibition of DNA fragmentation corresponded to the inhibition of peptide hydrolysis. The Asp-ase fragmentin was blocked by aspartic acid-containing tripeptide chloromethyl ketones, while the tryptase fragmentins were inhibited by arginine-containing chloromethyl ketones. The two tryptase fragmentins were slow acting and were partly suppressed by blocking proteins synthesis with cycloheximide in the YAC-1 target cell. In contrast, the Asp-ase fragmentin was fast acting and produced DNA damage in the absence of protein synthesis. Using a panel of unrelated target cells of lymphoma, thymoma, and melanoma origin, distinct patterns of sensitivity to the three fragmentins were observed. Thus, these three granule proteases make up a family of fragmentins that activate DNA fragmentation and apoptosis by acting on unique substrates in different target cells.

Amino Acid Sequence↗
PubMed1990

Calcium waves in mammalian heart: quantification of origin, magnitude, waveform, and velocity.

A dual, digital, indo-1 fluorescence imaging system was used to obtain high-speed ratiometric images of [Ca2+]i waves in single voltage-clamped mammalian cardiac cells. The spatiotemporal origin of [Ca2+]i waves in depolarized cells was detected as the spontaneous appearance, over 100-300 ms, of domelike regions of elevated [Ca2+]i, approximately 20 microns in diameter and 300 nM at the center. Images of [Ca2+]i taken at 67-ms intervals during propagation of [Ca2+]i waves revealed that the [Ca2+]i wave front was 1) constant in shape, 2) spatially steep, typically rising from 500 to 1200 nM in about 10 microns, and 3) propagating at constant velocity, typically 100 microns/s at 22 degrees C. The observed spatial and temporal patterns of origin and propagation of [Ca2+]i waves are consistent with the hypothesis that [Ca2+]i waves arise from propagating Ca2(+)-induced release of Ca2+ mediated by diffusion of cytosolic Ca2+. The [Ca2+]i waves are smaller in peak magnitude and can occupy a larger fraction of the cell than thought previously on the basis of indirect observations.

Animals↗
PubMed2002

Cloning and functional characterization of a beta-pinene synthase from Artemisia annua that shows a circadian pattern of expression.

Artemisia annua plants produce a broad range of volatile compounds, including monoterpenes, which contribute to the characteristic fragrance of this medicinal species. A cDNA clone, QH6, contained an open reading frame encoding a 582-amino acid protein that showed high sequence identity to plant monoterpene synthases. The prokaryotically expressed QH6 fusion protein converted geranyl diphosphate to (-)-beta-pinene and (-)-alpha-pinene in a 94:6 ratio. QH6 was predominantly expressed in juvenile leaves 2 weeks postsprouting. QH6 transcript levels were transiently reduced following mechanical wounding or fungal elicitor treatment, suggesting that this gene is not directly involved in defense reaction induced by either of these treatments. Under a photoperiod of 12 h/12 h (light/dark), the abundance of QH6 transcripts fluctuated in a diurnal pattern that ebbed around 3 h before daybreak (9th h in the dark phase) and peaked after 9 h in light (9th h in the light phase). The contents of (-)-beta-pinene in juvenile leaves and in emitted volatiles also varied in a diurnal rhythm, correlating strongly with mRNA accumulation. When A. annua was entrained by constant light or constant dark conditions, QH6 transcript accumulation continued to fluctuate with circadian rhythms. Under constant light, advanced cycles of fluctuation of QH6 transcript levels were observed, and under constant dark, the cycle was delayed. However, the original diurnal pattern could be regained when the plants were returned to the normal light/dark (12 h/12 h) photoperiod. This is the first report that monoterpene biosynthesis is transcriptionally regulated in a circadian pattern.

Amino Acid Sequence↗
PubMed2006

Insulin signaling and limb-patterning: candidate pathways for the origin and evolutionary diversification of beetle 'horns'.

Beetle 'horns' are rigid outgrowths of the insect cuticle used as weapons in contests for access to mates. Relative to their body size, beetle horns can be enormous. They protrude from any of five different regions of the head or thorax; they are curved, straight, branched or bladed; and their development is often coupled with the nutrient environment (male dimorphism) or with sex (sexual dimorphism). Here, we show that this extraordinary diversity of horns can be distilled down to four trajectories of morphological change--horn location, shape, allometry and dimorphism--and we illustrate how the developmental mechanisms regulating horn growth could generate each of these types of horn evolution. Specifically, we review two developmental pathways known to regulate growth of morphological structures in Drosophila and other insects: a limb-patterning pathway that specifies the location and shape of a structure, and the insulin pathway, which modulates trait growth in response to larval nutrition. We summarize preliminary evidence indicating that these pathways are associated with the development of beetle horns, and we show how subtle changes in the relative activities of these two pathways would be sufficient to generate most of the extant diversity of horn forms. Our objective is to intuitively connect genotype with phenotype, and to advocate an informed 'candidate gene' approach to studies of the developmental basis of evolution. We end by using this insight from development to offer a solution to the long-standing mystery of the scarabs: the observation by Darwin, Lameere, Arrow and others that this one family of beetles appeared to have a 'special tendency' towards the evolution of horns.

Animals↗
PubMed2002

Does "whole-word shape" play a role in visual word recognition?

To analyze the impact of outline shape on visual word recognition, the visual pattern of the stimuli can be distorted by size alternation. Contrary to the predictions of models that rely on outline shape (Allen, Wallace, & Weber, 1995), the effect of size alternation was greater for low-frequency words than for high-frequency words in a lexical decision task (Experiment 1). In Experiment 2, the effect of case type (lowercase vs. UPPERCASE) occurred for low-frequency words, but not for high-frequency words. The effect of neighborhood size was remarkably similar in the two experiments. The results can be readily explained in the framework of a resonance model (Grossberg & Stone, 1986), in which a mismatch between the original sensory pattern and the abstract orthographic code slows down the formation of a stable percept.

Attention↗
PubMed2002

[Vascular dementias].

Cerebrovascular disorders are the second most frequent cause of dementia in late life next to Alzheimer's disease. A recent community-based autopsy study has demonstrated that relevant cerebrovascular changes are much more prevalent in individuals aged 70+ years than previously assumed. Furthermore, the combination between cerebrovascular lesions and Alzheimer-type pathology is the most common neuropathological finding in elderly patients with dementia. There is still some uncertainty about which types of cerebrovascular changes are most likely to cause cognitive impairment including dementia and which pathogenetic mechanisms are involved. Without doubt, however, the vascular dementias are a heterogeneous group of diseases in terms of etiology, histopathology, and clinical appearance. According to the vessel calibres and perfusion territories that are preferentially affected a distinction is commonly made between the frequent subcortical small-vessel disease and the rare cortical large-vessel disease. With these morphological subtypes three major clinical variants are associated: dementia due to subcortical lacunes and white matter changes including Binswanger's disease, multi-infarct-dementia, and dementia due to singular strategic infarcts. In most cases of dementia of cerebrovascular origin the pattern of intellectual impairment is frontal or subcortical, in contrast to the typical cortical presentation of Alzheimer's disease. Deterioration of executive function and attention as well as changes in personality, rather than memory loss, are the predominant symptoms. Therefore the current diagnostic criteria for dementia are poorly suited for the detection of vascular dementias. None of the criteria that have been specifically proposed for the diagnosis of vascular dementias provide clear guidelines for evaluating the causal relationship between cerebrovascular lesions and psychopathological findings. Further research will reveal whether clinical diagnosis can be improved by taking into account the heterogeneity of cerebrovascular diseases. A large proportion of dementias of cerebrovascular origin may be preventable by treating the risk-factors for stroke. Once significant cognitive impairment has occurred, however, there is no established pharmacological treatment for the vascular dementias to date. Only recently results of placebo-controlled clinical trials have become available showing that cholinergic treatment strategies are effective in vascular dementia and in dementia due to combined vascular and neurodegenerative pathologies.

Brain↗
PubMed1981

Clinical investigation of the menstrual cycle. III. Clinical, endometrial, and endocrine aspects of luteal defect.

This study was intended to correlate different clinical and biologic parameters to better define luteal insufficiency (LI) and to contribute to a better understanding of its origin. Endometrial patterns were used as the basis for classification of clinical cases. Of 328 outpatients with menstrual disorders and/or infertility, 88 were considered to have LI. Their cycles were compared with 79 normal cycles. Two different principal endometrial patterns of LI are described: pure LI, when the endometrium is more than 2 days out of phase; and LI with persistent estrogenic influence, when the histologic estrogenic stigmata are excessive during the luteal phase. Basal body temperature charts demonstrated menstrual cycle disturbances: either ovulation delay or a slow increase in temperature (longer than 2 days). Plasma steroid concentrations also demonstrated a perturbation of the entire menstrual cycle: progesterone levels were statistically significantly lower in LI than in normal cycles and this defect was worse when the estrogenic influence was persistent; the preovulatory estradiol peak was disturbed in all circumstances, as was the concentration of endometrial steroid receptors. These simultaneous abnormalities strongly suggest a central origin of LI.

Adult↗