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Research data strongly suggest that osteoarthritis of the hip occurs statistically more often on the right side. A possible contributing factor to this right-sided bias in frequency may be that the articular cartilage on the right hip is subjected to relatively higher muscular-based forces throughout a lifetime. As an initial attempt to study this possibility, this research examined healthy persons to determine the existence of a "dominant" hip similar to that expressed for handedness. Electromyographic (EMG) analysis was used to compare the electrical activity between the right and left hip abductor muscles during a standardized standing work task using 40 right-handed and 40 left-handed healthy subjects. Analysis of the data showed that the hip muscle on the side of the subject's handedness produced higher normalized EMG activity than did the opposite hip; however, the differences were not all statistically significant. The trend of this data set, however, warrants further research into a possible association between hip dominance, asymmetrical muscle use, and the development of hip osteoarthritis.
Arthritis Care Res 1990 Sep
PMID:An electromyographic analysis of the hip abductor muscles during a standing work task. 228 50

Rohrer's ponderal index in newborns (birth weight/heights x 100) has been used as an indicator of fetal growth status, especially to assess asymmetrical intrauterine growth retardation. Because low birth weight and intrauterine growth retardation tend to recur in sibships, we examined patterns of sibling correlation in the ponderal index in 795 live term (greater than or equal to 37 weeks) singleton sibling pairs without birth defects born between 1966 and 1986 and fathered by male US Army veterans participating in a nationwide health study. Data on birth weight, length, gestational age, and other maternal and infant health characteristics were abstracted from hospital-of-birth medical records. The correlation coefficient of ponderal index in sib pairs was 0.24 (p less than 0.001). Compared with 627 infants who had a prior sib with a ponderal index between the 10th and 90th percentiles, 92 infants who had a prior sib with ponderal index less than the 10th percentile had a lower mean ponderal index and a higher proportion with ponderal index less than the 10th percentile (13.0% vs. 8.5%). On the other hand, 76 infants who had a prior sib with ponderal index greater than the 90th percentile had a higher mean ponderal index and higher proportion with ponderal index greater than the 90th percentile (17.1% vs. 10.2%). The clustering of ponderal index in siblings persisted after controlling for factors such as race, gender, maternal age, gravidity, year of birth, gestational age, pregnancy complications, and prior maternal illnesses. The findings point to the presence of genetic and/or maternal factors affecting the growth status of term newborn infants. The significance of the ponderal index needs to be examined in future genetic and epidemiologic studies of intrauterine growth.
Am J Epidemiol 1990 Sep
PMID:The ponderal index in term newborn siblings. 238 61

The location-specific firing of hippocampal place cells can easily be brought under the control of experimenter-defined cues. Nevertheless, there is evidence that these firing fields are not determined just by immediate sensory input, but also by earlier states of the nervous system (O'Keefe and Speakman, 1987). Here, we report further on the roles of multiple visual cues and mnemonic processes in determining the firing of place cells. Rats were trained to chase food pellets in a cylinder with homogeneous gray walls and 1 white cue card. After a cell's field was recorded in this "standard" condition, probe sessions were conducted in which a second card was placed 180 degrees away from the first. This configuration created a diametrically symmetrical environment in which pairs of locations 180 degrees apart were identical with respect to views of the wall and cards. If place cells are strongly controlled by these immediately available views, firing in the 2-card configuration should be diametrically symmetrical. Alternatively, because the rat moves freely in the cylinder, information is available that pairs of visually identical places are not truly the same. If some mnemonic process stores and updates information about the rat's paths during the session, it is possible that the firing pattern will be different in 2 such places, especially because the original training was conducted in the 1-card, asymmetrical environment. Thirteen of 18 cells had a single, asymmetric firing pattern after the second card was introduced; the field was the same size and shape as in the 1-card configuration and in the same spatial relation to 1 of the 2 cards. The field position during 2-card sessions could be rotated 180 degrees by starting the rat by one card or the other. In further probe sessions in which the cue cards, entry location, and background cues were, in various combinations, rotated in relation to each other, these cells always showed a single field, similar in size and shape to that in the standard, and in the same relationship as in the standard to as many cues as possible. The remaining 5 cells showed complex changes over repeated 2-card sessions, and 3 of these showed paired fields, 180 degrees apart for at least some of the sessions. In one case, the second field disappeared with repeated exposures to 2 cards; in another, the second field persisted when only 1 card was used. We conclude that place cells are influenced both by the immediate sensory configuration and by internal neural states related to earlier experience in the environment.
J Neurosci 1990 Sep
PMID:Firing properties of hippocampal neurons in a visually symmetrical environment: contributions of multiple sensory cues and mnemonic processes. 239 74

Double post-embedding immunolabeling of both tyrosine hydroxylase and glutamate decarboxylase on 1-micron semi-thin sections allowed the visualization of numerous endings that use gamma-aminobutyrate as a transmitter apposed to dopaminergic cell bodies in the periventricular-arcuate hypothalamic complex. Up to fifteen glutamate decarboxylase-positive contacts per tyrosine hydroxylase-positive cell profile could be observed. In some favourable planes of section glutamate decarboxylase-positive endings were also seen in close apposition to proximal dopaminergic dendrites. About 250 tyrosine hydroxylase-positive cell profiles, whose diameter approached the maximum diameter of the dopaminergic cells, were surveyed. An average of 7.4 glutamate decarboxylase-positive contacts were counted on these profiles. From these figures it was estimated that a dopaminergic cell body was contacted on average by 75-175 terminals that use gamma-aminobutyrate as a transmitter. At the electron-microscopic level, the nature of these contacts was investigated by a method combining radioautographic detection of cell bodies having taken up tritiated dopamine and pre-embedding immunostaining of glutamate decarboxylase containing endings. Glutamate decarboxylase-positive axon terminals were seen apposed to somatic and dendritic elements. On some favorable planes of section, they were found to be engaged in morphologically defined synaptic complexes of the symmetrical or asymmetrical type. A number of the postsynaptic perikarya were labelled by tritiated dopamine and, in agreement with the light microscopic observations, they were frequently seen in contact with more than one immunopositive ending. The present findings provide a morphological substratum for a direct gamma-aminobutyrate control of the tuberoinfundibular dopaminergic neurons. Such a control could account more particularly for the central, stimulatory effects of gamma-aminobutyrate on prolactin secretion.
Neuroscience 1985 Sep
PMID:Glutamate decarboxylase-immunoreactive boutons in synaptic contacts with hypothalamic dopaminergic cells: a light and electron microscopy study combining immunocytochemistry and radioautography. 242 13

The synaptic organization of terminals originating either from the spinal cord (spinothalamic) or from the dorsal column nuclei (lemniscal) was investigated in the ventrobasal complex of the rat thalamus. Wheatgerm agglutinin conjugated to horseradish peroxidase was used as an anterogradely transported axonal tracer, using benzidine dihydrochloride as a chromogen for the identification by electron microscopy of spinal and lemniscal projections to the ventrobasal thalamus. A double anterograde tract tracing strategy, based labeling by wheatgerm agglutinin conjugated to horseradish peroxidase of spinal terminals and simultaneous visualization of lemniscal terminals identified by Wallerian degeneration induced by lesion of the neurons of origin in the dorsal column nuclei, was used to compare the postsynaptic elements contacted by the two pathways and to look for a possible convergence of the two pathways onto single thalamic neurons. Spinal and lemniscal terminals are large (2-2.5 microns mean average diameter) terminals containing several mitochondria and numerous rounded vesicles. A quantitative analysis of the mean average diameters of the terminals revealed that one could not differentiate between synapses formed by the two pathways on a morphological basis. Terminals of the two pathways make asymmetrical contacts (Gray type I) with dendrites of varying diameter, dendritic protrusions, and cell somata. A quantitative analysis of the least diameter of the postsynaptic elements demonstrates projections of the two systems to different, partially overlapping regions of thalamic neurons. Lemniscal terminals originating from the dorsal column nuclei frequently contact cell somata; axosomatic spinothalamic contacts are uncommon. In addition, lemniscal projections tend to contact more proximal dendrites than do spinal projections, and this differential synaptic organization is statistically significant. From a functional point of view, this differential synaptic organization might indicate that lemniscal inputs have greater influence than spinal inputs in affecting the activity of thalamic neurons. Labeled spinothalamic terminals contact the same dendritic profile as do degenerating lemniscal terminals in about 10% of single sections. Because the present study did not include a complete reconstruction of ventrobasal complex neurons of the thalamus or even regions of dendritic arbors, the degree of convergence is likely to be significantly underestimated. These findings indicate that the anatomical basis exists for an interaction between nociceptive and non-nociceptive somesthetic systems at the level of single ventrobasal neurons of the thalamus of the rat.
Neuroscience 1987 Sep
PMID:The differential synaptic organization of the spinal and lemniscal projections to the ventrobasal complex of the rat thalamus. Evidence for convergence of the two systems upon single thalamic neurons. 244

99Tcm-dextran was evaluated as a lymphoscintigraphic agent in 10 normal volunteers and 24 patients with breast cancer. 99Tcm-dextran (0.5-1 mCi) in a volume of 0.1-0.2 ml was injected into the posterior rectus sheath in the subcostal site on one side. Scintigrams were obtained at 2-2.5 h after injection and the injection was repeated on the other side. The final image was taken at 4.5-5 h after the first injection. The normal distribution of lymph nodes and anatomical variations in scintigraphic images were first determined in normal subjects. In the patient group, eight scintigrams were evaluated as pathological and the rest as normal. In the 25 women whose lymphoscintigrams were normal the mean number of parasternal nodes visualized was six (range: 3-11). Bilateral symmetrical or asymmetrical chain was observed in 20 subjects (80%) and unilateral chain in five subjects (20%). There was cross-drainage in five subjects (20%). Supraclavicular lymph nodes were visualized in 11 subjects (44%). Varying abnormal images were obtained in eight patients. Our results are in good agreement with those reported in the literature, using radiocolloids. It is concluded that 99Tcm-dextran is a promising agent and may well replace radiocolloids because of the simplicity of the labelling procedure, stability of the label, easy availability and low cost.
Nucl Med Commun 1988 Sep
PMID:Parasternal lymphoscintigraphy using 99Tcm-dextran. 246 Aug 9

The mucosa that lines the airways is covered with a fluid film forming a hypophase between mucus and cell surface. To study the function of this epithelium aims at describing the mechanisms by which fluid is normally produced. Another goal to be pursued consists in looking for the origin of pathological situations, such as cystic fibrosis, in which the functioning of epithelial cell is altered. The elucidation of transport mechanisms present in the apical and in the basolateral membrane results in a conceptual model that illustrates the asymmetrical functioning of epithelial cells. Recent discoveries enlarge our understanding of membrane transport processes; in particular, a concerted, reciprocal regulation of the activity of both membranes was shown to be exerted via the intracellular composition. The tracheal epithelium absorbs Na+ and secretes Cl-. These two transports are active and electrogenic; their sum corresponds approximately to the short-circuit current measured in vitro. Na+ absorption is sensitive to amiloride from the luminal side and also to ouabain added to the serosal compartment. The process is a primary active transport, analogous to that found in amphibian epithelia or in mammalian colon. Cl- secretion is abolished by furosemide (or bumetanide), by ouabain or by Na+ suppression in the serosal incubation solution. The mechanism is a secondary active transport: Cl- influx across the basolateral membrane is coupled to Na+ (probably through Na+, K+, Cl- symport); energy is dissipated by the Na+-K+-ATPase localised in the basolateral membrane. Thus, Na+ is recirculated across that membrane by the pump activity, which maintains a favorable gradient for influx via the symport. Cl- efflux takes place by diffusion through the luminal membrane. This model applies to other epithelia in which Na+-coupled Cl- secretion was shown to take place. It is confirmed by isotopic fluxes measurements and by electrophysiologic properties of the apical and the basolateral membrane. Various agents are known to influence ion transports. In particular Cl- secretion is stimulated by substances that increase the intracellular concentration of cyclic AMP. At the membrane level, the number of active Cl- channels in the apical membrane is primarily controlled, then the basolateral membrane K+ permeability. Yet, species differences are worth to note: the trachea of the cow is barely sensitive to agents that exert a marked action on dog trachea. The tracheal epithelium is used as an experimental model for studying cystic fibrosis, a disease in which the apical membrane is almost devoid of functional Cl- channels, so that Cl- permeability is quite low.(ABSTRACT TRUNCATED AT 400 WORDS)
Arch Int Physiol Biochim 1988 Sep
PMID:[Physiology of the tracheal epithelium]. 246 15

The purpose of this investigation was to study the effects of a distinct type of phospholipase C on sarcolemmal Na+-Ca2+ exchange. With this phospholipase C (Staphylococcus aureus), treatment of cardiac sarcolemmal vesicles resulted in a specific hydrolysis of membrane phosphatidylinositol. This hydrolysis of phosphatidylinositol also released two proteins (110 and 36 kDa) from the sarcolemmal membrane. Phospholipase C pretreatment of the sarcolemma resulted in an unexpected stimulation of Na+-Ca2+ exchange. The Vmax of Na+-Ca2+ exchange was increased but the Km for Ca2+ was not altered. This stimulation was specific to the Na+-Ca2+ exchange pathway. ATP-dependent Ca2+ uptake was depressed after phospholipase C treatment, but passive membrane permeability to Ca2+ was unaffected. Sarcolemmal Na+,K+-ATPase activity was not altered, whereas passive Ca2+ binding was modestly decreased after phospholipase C pretreatment. The stimulation of Na+-Ca2+ exchange after phosphatidylinositol hydrolysis was greater in inside-out vesicles than in a total population of vesicles of mixed orientation. This finding suggests that the cardiac sarcolemmal Na+-Ca2+ exchanger is functionally asymmetrical. The results also suggest that membrane phosphatidylinositol is inhibitory to the Na+-Ca2+ exchanger or, alternatively, this phospholipid may anchor an endogenous inhibitory protein in the sarcolemmal membrane. The observation that a transsarcolemmal Ca2+ flux pathway may be stimulated solely by phosphatidylinositol hydrolysis independently of phosphoinositide metabolic products like inositol triphosphate is novel.
J Biol Chem 1989 Sep 15
PMID:Role of phosphatidylinositol in cardiac sarcolemmal membrane sodium-calcium exchange. 254 59

Recently a subset of chronic demyelinating inflammatory polyneuropathies with asymmetrical involvement limited to upper limbs, at least at the onset, resembling a multifocal mononeuropathy has been described. Electrodiagnostic testing disclosed multifocal CB outside the common entrapment sites has been described. We report a 55 years old man with a 4 years history of paresis, numbness, fasciculations, myokymia, cramps and mild amyotrophy. Electrophysiological evaluation showed proximal multifocal conduction block and abundant spontaneous activity as fasciculations, myokymia and scarce denervation activity. The importance of taking into account this entity in the differential diagnosis of patients with suspected mononeuritis multiplex or motoneuron disease is emphasized. The nosologic place of this entity is also discussed.
Med Clin (Barc) 1989 Sep 09
PMID:[Multifocal polyneuropathy with persistent conduction blockage. A new subset of chronic inflammatory polyneuropathies]. 255 98

Corticotropin-releasing factor (CRF) and dopamine (DA) are important integrators of the endocrine and autonomic response to stress. CRF neurons in the anterior portions of the periventricular nucleus (PV) and parvocellular paraventricular nucleus (pvPVN) occur close to A14 DA neurons in these same locations. Since CRF has been shown to act as an excitatory neurotransmitter, possible CRF interactions with the DA system were investigated using double-label immunocytochemistry. Coronal vibratome sections through the PV and pvPVN were obtained from colchicine-treated and nontreated juvenile female cynomolgus macaques. They were sequentially immunostained for tyrosine hydroxylase (TH) (to identify DA neurons) with PAP and DAB, and for CRF using 15 nm colloidal gold. By light microscopy, areas of coincidence of TH- and CRF-immunoreactive cell bodies in the PV and pvPVN were obvious, but double-stained elements were not observed. By electron microscopy, asymmetrical synapses frequently occurred between CRF axons and TH dendrites or somata. Symmetrical axosomatic synapses sometimes appeared adjacent to these CRF/TH synapses, while symmetrical axoaxonic synapses were rare. We conclude that CRF neuronal efferents synaptically activate A14 DA neurons in the primate PV and pvPVN. Parallel CRF/DA symmetrical synapses also suggest coexistence of a companion transmitter within some of these same CRF neurons. Our own previous work and recent independent studies indicate that this transmitter is probably GABA. Thus the CRF neuronal system, which is known to alter secretion of several pituitary hormones, may also act through hypothalamic periventricular DA neurons to mediate other responses to stress.
Neuroendocrinology 1989 Sep
PMID:Corticotropin-releasing factor neurons innervate dopamine neurons in the periventricular hypothalamus of juvenile macaques. Synaptic evidence for a possible companion neurotransmitter. 257 55


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