Amphibian olfactory receptor neurons express olfactory marker protein. Expression of olfactory marker protein (OMP) in olfactory receptor neurons (ORNs) in two amphibians was investigated by immunohistochemical methods. The OMP immunoreactivity was observed in the cilia, apical dendritic knobs, dendrites and somas of ORNs; the axons of ORNs also showed intense immunoreactivity for OMP throughout their course from the olfactory epithelium to the glomerular layer of the olfactory bulb. Seven days after olfactory nerve transection in salamander, the number of OMP-positive ORNs was markedly reduced in the ipsilateral epithelium. The results demonstrate that amphibian ORNs express OMP and confirm its phylogenetic conservation across diverse species.


Chronic fluoxetine treatment reduces hypothalamic vasopressin secretion in vitro. Patients with obsessive-compulsive disorder (OCD) hypersecrete the arousal producing neurohormone arginine vasopressin (AVP) into the cerebrospinal fluid and plasma. Because OCD responds preferentially to potent serotonin uptake inhibitors, we compared the effect of chronic fluoxetine treatment to that of other antidepressants (trazodone and desipramine) on AVP release from rat hypothalamic organ culture and showed that only fluoxetine significantly reduced in vitro AVP release.


Basal extracellular dopamine levels in the nucleus accumbens are decreased during cocaine withdrawal after unlimited-access self-administration. The effects of withdrawal from cocaine on extracellular dopamine (DA) levels in the nucleus accumbens (NAC) were examined by intracranial microdialysis in awake rats after periods (9.5-21.75 h) of unlimited-access, intravenous cocaine self-administration. Cocaine withdrawal was associated with significant reductions in basal DA overflow that persisted up to 12 h. Maximal inhibition of DA release (mean +/- S.E.M. 66.15 +/- 3.30 percent of basal levels) was observed between 4-6 h after cessation of cocaine intake and was positively correlated (r = 0.88) with the duration of the preceding self-administration episode. The results suggest that suppression of basal DA release in the NAC is an adaptive consequence of sustained cocaine exposure and may in part underlie the post-cocaine anhedonia observed in behavioral models of cocaine withdrawal.


Amyloid precursor protein is localized in growing neurites of neonatal rat brain. Previous studies have indicated that amyloid precursor protein (APP) might be a trophic agent in the nervous system, possibly through the regulation of cell adhesion and the protease/protease inhibitor activity. Additionally, APP is upregulated during the development of the nervous system. In order to further study the role of APP in neuritic outgrowth, we examined the patterns of distribution of APP in the immature neonatal rat brain (P1). Laser-scanning confocal imaging of double-immunolabeled sections showed that a subpopulation of the anti-GAP43-immunoreactive outgrowing neurites contained APP immunoreactivity in the neocortex and hippocampus. These fine, long neuritic processes were also positive with antibodies against phosphorylated neurofilaments and were glial fibrillary acidic protein (GFAP) negative. In addition, anti-APP strongly immunolabeled neurons in the inner cortical layers, while GAP43 strongly immunolabeled the neuropil surrounding them. These observations are consistent with a previous study where APP was localized to aberrant sprouting neurites and suggest a possible role for APP in neuritic outgrowth in plaques of patients with Alzheimer's disease (AD), which might explain the abnormal neuritic response found in AD.


Comparison of anticonvulsant effects of valproic acid entrapped in positively and negatively charged liposomes in amygdaloid-kindled rats. Intraperitoneal injection of free valproic acid (VPA) suppressed amygdaloid-kindled seizure 1 h after injection in rats, but had no effect at 24 h. VPA entrapped in positively charged liposomes showed a prolonged anticonvulsant effect lasting for 2 days, while the effect evaluated at 1 h was not different from that with free VPA. VPA entrapped in negatively charged liposomes exerted a significantly stronger effect at 1 h than did free VPA, while it had no significant effect at 24 h. These results suggest that surface charges on liposomes play an important role in modifying the anticonvulsant effect of VPA.


Effects of epidermal growth factor and basic fibroblast growth factor on generation of long-term potentiation in the dentate gyrus of fimbria-fornix-lesioned rats. The effects of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) on long-term potentiation (LTP) in the dentate gyrus in vivo were investigated in fimbria-fornix (FF)-lesioned rats. Transection of FF resulted in decreased frequency of LTP generation. Intracerebroventricular injection of EGF (50 ng) and bFGF (50 ng) significantly facilitated LTP generation in the FF-lesioned rats. These results suggest that EGF and bFGF can promote the hippocampal LTP impaired by loss of subcortical afferents.


Differences in the dopaminergic innervation of the electroreceptive and mechanoreceptive medullary lateral line nuclei of the ray, Raja radiata. An immunohistochemical study was made of the octavolateral centres in the medulla of a cartilaginous fish, using an antibody specific for dopamine. No immunopositive cell bodies were observed but dopaminergic fibres were present in parts of the region. The overlying cerebellar crest was devoid of dopamine; the dorsal (electroreceptive) nucleus was poorly innervated, but the medial (mechanoreceptive) nucleus received a rich dopaminergic innervation comprising very fine, varicose fibres.


Neuromelanin-containing neurons of the substantia nigra accumulate iron and aluminum in Parkinson's disease: a LAMMA study. The Laser Microprobe Mass Analyzer (LAMMA) is a sensitive instrument for identifying and localizing trace elements in tissue samples. Using LAMMA, we have examined melanin-containing neurons of the substantia nigra in patients with Parkinson's disease (PD) and controls. We found that iron significantly accumulates within neuromelanin granules of patients with PD compared to controls. Increased aluminum was found in the neuromelanin granules of 2 of 3 PD cases but in no controls. The accumulation of iron and aluminum, which are known to promote oxidant stress, may account for the selective degeneration of neuromelanin-containing neurons in PD.


HIV-1 envelope protein evokes intracellular calcium oscillations in rat hippocampal neurons. Treatment of single rat hippocampal neurons with 200 pM recombinant HIV-1 envelope glycoprotein, gp120, resulted in large increases in the intracellular free calcium concentration ([Ca2+]i) as measured with indo-1-based microfluorimetry. Three patterns of [Ca2+]i increases were observed: in one pattern the [Ca2+]i rose rapidly and transiently as a single peak, in a second pattern gp120 induced [Ca2+]i oscillations that subsided when the protein was removed, and in a third pattern the oscillations continued long after washout of gp120. Both single peak and oscillatory [Ca2+]i increases were completely blocked by the Ca2+ channel blocker nitrendipine (1 microM). The sustained oscillatory responses were also blocked completely and reversibly by the N-methyl-D-aspartate (NMDA) receptor antagonist CGS19755 (10 microM) and the Na+ channel blocker tetrodotoxin (1 microM). Complete block by antagonists of Ca2+, Na+, and NMDA-gated ion channels suggests that at least two cells are required to maintain the [Ca2+]i oscillations. We hypothesize that gp120 acts as an excitotoxin by increasing synaptic activity in the network of neurons established in primary culture.


The pontine parabrachial region mediates some of the descending inhibitory effects of stimulating the anterior pretectal nucleus. Electrical stimulation of the anterior pretectal nucleus (APtN) elicits antinociception by inhibiting the responses of spinal multireceptive neurones to noxious stimuli. This descending inhibition is mediated, in part, by activating cells in the ventrolateral medulla. Neuronal tract tracing has previously shown that the APtN also projects directly to the pontine parabrachial region (PPR). The PPR, investigated by Katayama et al. (Brain Res., 296 (1984) 263-283), corresponds to the cholinergic cell group Ch5 of Mesulam et al. (Neuroscience, 10 (1983) 1185-1201). In this study, the pathway from APtN to PPR was investigated using urethane anaesthetised rats. Electrical stimulation (single square wave 0.2 ms pulses, 1-10 V, 5 Hz) of the APtN potently excites 40% of the cells recorded in the PPR. In the reverse experiment, stimulation of the PPR at the same parameters excited 36% of the cells recorded in the APtN. The contribution of this pathway to the spinal inhibitory effects of APtN stimulation was then examined. Unanaesthetised animals received electrical stimulation to the APtN (35 microA r.m.s., 15 s) and the increase in tail-flick latencies was measured. Bilateral electrolytic lesions of the PPR caused a 67% reduction of the antinociceptive effect of APtN stimulation. In urethane anaesthetised rats, microinjection of tetracaine into the PPR blocked the inhibition of multireceptive dorsal horn neurones caused by APtN stimulation (20 s train of 50 microA square wave 0.1 ms pulses, 100 Hz). In conclusion, these experiments strongly sugget that the PPR may be an important part of a descending antinociceptive pathway originating in the APtN.


Primary culture of postnatal rat hypothalamic neurons in astrocyte-conditioned medium. Mature functional hypothalamic neurons of male and female rats (21-day postnatal) were successfully cultured without attachment to non-neuronal cells in serum-free astrocyte-conditioned medium (ACM). A novel cell-collecting method was designed for these vulnerable cells by allowing the dissociated cell suspension to stand in a vertically held, wide-tipped syringe so that the cells were concentrated near the lower liquid surface, from which position they could be easily dropped into the medium, leaving most of the small debris in the syringe. This method made it possible to study statistically the survival of cultured neurons. It was impossible to collect many viable cells by the commonly used dissociating technique for fetal rat brain. However, neuron-like cells with a few processes could be isolated from sliced hypothalamic tissues by means of enzymatic and mechanical treatments. The original processes disappeared within 1-2 days and some new processes were generated after 2-3 days in vitro; the cells survived for 28 days in vitro. The cells were identified as neurons by the immunostaining method for microtubule-associated protein 2 (MAP2) and neurofilament (NF). Such neurons were obtained from every site of hypothalamic tissue sampled. These phenomena were not observed in chemically-defined medium (CDM), CDM supplemented with basic fibroblast growth factor (bFGF), epidermal growth factor (EGF) or nerve growth factor (NGF).


Systemic morphine reduces GABA release in the lateral but not the medial portion of the midbrain periaqueductal gray of the rat. Neuroanatomical, electrophysiological and pharmacological studies have provided indirect evidence indicating that GABAergic neurons play a key role in opiate analgesia mediated by the midbrain periaqueductal gray (PAG) and ventromedial medulla. Although these studies suggest that systemic administration of opiates inhibits GABA release in the PAG, there have been no investigations to date that have directly examined this issue. The present study was thus designed to determine whether systemic morphine injection inhibits GABA release in the PAG of awake, freely moving rats using in vivo microdialysis and subsequent HPLC analysis. Extracellular levels of GABA, glutamate, aspartate, glycine, homocysteic acid and taurine were monitored with the microdialysis technique in either the lateral or medial portion of the ventrocaudal PAG in unanesthetized, unrestrained rats. Amino acid release was induced by infusing veratridine (75 microM, a sodium channel activator) directly through the dialysis probe. The effect of veratridine alone and the effect of veratridine in the presence of systemic morphine on the concentrations of amino acids in the PAG dialysate were determined. There were no significant differences in the basal concentrations of GABA, taurine, aspartate, glutamate, homocysteic acid and glycine between dialysates collected from the medial versus the lateral ventrocaudal PAG. Glycine, taurine and glutamate were present in the highest concentrations in dialysis samples both before and after treatment with veratridine, whereas GABA, homocysteic acid and aspartate were present in the lowest concentrations. Perfusion of veratridine into the ventrocaudal PAG resulted in significant elevation of all amino acids investigated. Except for taurine, no significant difference in veratridine-induced release between the lateral and medial PAG was observed. Tetrodotoxin (TTX) significantly blocked veratridine-induced release of GABA, aspartate, glutamate, glycine and taurine but not homocysteic acid. When rats were injected with morphine (10 mg/kg i.p.), veratridine-induced release of GABA was selectively and significantly decreased in the lateral but not the medial PAG as compared to control rats injected with saline followed by veratridine perfusion. Systemic injection of morphine or saline caused no significant change in the basal concentration of amino acids in PAG dialysate samples. These findings are consistent with the proposed mechanism of action of morphine in the lateral ventrocaudal PAG and offer the first direct evidence that systemic opiates decrease GABA release in this midbrain region.


Effects of prazosin on the blood-brain barrier during experimental autoimmune encephalomyelitis. Alterations in normal function of the blood-brain barrier (BBB) are important in the pathophysiology of multiple sclerosis and its laboratory counterpart, experimental autoimmune encephalomyelitis (EAE). As part of studies on drugs that affect vascular tone in rats with EAE, we have shown previously that the specific alpha 1-adrenoreceptor antagonist, prazosin, suppressed clinical and pathologic disease. In the present study we used quantitative morphometric analysis of capillary endothelium and the tracer horseradish peroxidase (HRP) to define effects of this drug on vascular events associated with central nervous system edema. In prazosin-treated and saline-treated EAE rats, protein extravasation in the spinal cord correlated with clinical presentation. Consistent with our previous data, the results showed that increased edema was associated with increased vesicular content of capillary endothelium. In prazosin-treated rats with no clinical signs, vesicular content was comparable to that found in normal animals. With increasing severity of disease, vesicular content increased and mitochondrial content decreased. In both prazosin- and saline-treated rats, mitochondrial content was reduced even when clinical signs were slight, and sharply declined when clinical signs increased. These results suggest that damage to mitochondria may be associated with early pathological events. In prazosin-treated animals, HRP accumulated in pericytes, suggesting that these cells were a target for the action of prazosin and may restrict the extravasation of fluid into the perivascular parenchyma. Our results underscore the presence of capillary changes associated with inflammation of the central nervous system, in addition to the well-recognized cellular inflammation that is targeted to the venular bed. The extent of capillary changes was closely associated with extent of tracer leakage in the spinal cord and support the conclusion that transcytotic vesicles are involved in transport of edema fluid during EAE, and that high mitochondrial levels are important for the normal function of BBB endothelium.


A1 neurons and excitatory amino acid receptors in rat caudal medulla mediate vagal excitation of supraoptic vasopressin cells. Extracellular recordings from the supraoptic nucleus of the rat established that vasopressinergic neurosecretory cells were excited by stimulation of cervical but not abdominal vagal afferents. This response was absent or significantly attenuated after microinjection of gamma-aminobutyric acid into a region of the caudal medulla known to contain the A1 noradrenaline cell group. Consistent with the possible involvement of the A1 group, vagal stimulation approximately doubled the frequency of proto-oncogene expression in A1 noradrenaline neurons, as indicated by the occurrence of nuclear Fos-like immunoreactivity in tyrosine hydroxylase-positive neurons of the caudal ventrolateral medulla. Finally, A1 region microinjection of either the N-methyl-D-aspartic acid (NMDA) receptor antagonist DL-2-amino-5-phosphonovaleric acid (APV), or the non-NMDA antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), significantly reduced vasopressin cell responses to vagal stimulation. These findings suggest that: (i) the A1 group is an essential component in a pathway which relays facilitatory vagal input of cardiopulmonary origin to neurosecretory vasopressin cells, and (ii) the activation of A1 neurons in this pathway involves both NMDA and non-NMDA excitatory amino acid receptors, an observation consistent with an input to A1 cells which generates 'mixed' excitatory postsynaptic potentials.


Convergence and segregation of septal and median raphe inputs onto different subsets of hippocampal inhibitory interneurons. The convergence and segregation of medial septal and median raphe afferents in the innervation of different subpopulations of GABAergic interneurons was investigated in the rat hippocampal formation. Following local injections of 5,7-dihydroxytryptamine into the median raphe nucleus destroying all serotonergic neurons, iontophoretic injections of Phaseolus vulgaris leucoagglutinin (PHAL) into the medial septum resulted in anterograde labelling of axons in the hippocampus. The labelled varicose fibres made multiple contacts with calbindin D28K-, parvalbumin-, and cholecystokinin-immunoreactive interneurons. These results disproved the possibility that PHAL-labelled afferents innervating hippocampal interneurons following septal PHAL injections would have been raphe axons passing through the injection site. In the second set of experiments a double anterograde tracing technique (PHAL from the septum and biotinylated-PHAL from the median raphe) and a triple or double immunostaining procedure was used to determine the types of interneurons (calbindin D28K-, parvalbumin-, or cholecystokinin-immunoreactive) innervated by one, or the other, or both pathways. The results showed that parvalbumin-containing neurons were innervated by septal afferents but avoided by raphe axons, whereas calbindin D28K-containing cells, and to a smaller extent cholecystokinin-containing cells served as targets for both pathways. In some cases the same individual calbindin D28K- or cholecystokinin-containing neurons received multiple contacts from afferents of both septal and raphe origin. Thus, our results indicate that different subcortical nuclei modulate largely different inhibitory circuits in the hippocampal formation. However, considering the occasional convergence of the two subcortical nuclei not only onto the same type, but even onto the same individual calbindin D28K-containing interneurons, we propose that a particular inhibitory function, most probably feed-forward inhibition in the distal dendritic region, is under the control of both pathways.


Progressive transformation of the cytoskeleton associated with normal aging and Alzheimer's disease. Transitional and end-stage forms of neurofibrillary tangles associated with normal aging and Alzheimer's disease were identified using thioflavine staining combined with tau and neurofilament protein immunofluorescence. Normal aging was marked by transitional pathology in layer II of the entorhinal cortex but no neurofibrillary tangles in prefrontal cortex, whereas, in Alzheimer's disease cases, layer II entorhinal neurons had progressed to end-stage neurofibrillary tangles and the prefrontal cortex contained a high representation of transitional forms of the neurofibrillary tangle.


Magnetic resonance imaging of neural transplants in rat brain using a superparamagnetic contrast agent. Rat fetal brain tissue was incubated in vitro with superparamagnetic ferrite particles covalently coupled to the lectin wheat germ agglutinin (WGA) and transplanted into the adult rat striatum. At 6 days and at 3 weeks post-surgery the transplants were observed on T1 weighted magnetic resonance (MR) images of the rat head as an area of relatively low signal intensity which could be clearly differentiated from the higher signal intensity produced by the host brain. Histological analysis revealed that the ferrite particles were largely restricted to the transplant in a patchy distribution. The ferrite particles were associated with cells having an apparent normal morphology. Superparamagnetic ferrite particles act as potent MR contrast agents and can be used to label transplanted cells. The labeled cells are apparently not adversely affected by the WGA-ferrite particles and can be monitored for at least three weeks in vivo using noninvasive MR imaging.


Neuroprotective effect of protein kinase C inhibitors on oxygen/glucose free-induced decreases in 2-deoxyglucose uptake and CA1 field potentials in rat hippocampal slices. Staurosporine, a protein kinase C inhibitor, was found to produce a neuroprotective effect against an ischemic insult in both gerbils and rats in vivo. We have demonstrated that rat hippocampal slices exposed to oxygen/glucose-free medium showed decreases in 2-deoxyglucose (2-DG) uptake and CA1 field potentials elicited by the stimulation of Schaffer collaterals. Therefore we examined the effect of protein kinase C inhibitors on oxygen/glucose free-induced impairments of 2-DG uptake and CA1 field potentials. Pretreatment with staurosporine, K252a and H-7 attenuated decreases in 2-DG uptake and CA1 field potentials. Treatment with phorbol ester, a protein kinase C activator, for a long period (90 min) was found to induce a down-regulation of protein kinase C activity. Therefore we examined the effect of pretreatment with phorbol ester for 90 min on oxygen/glucose free-induced decreases in 2-DG uptake and CA1 field potentials. These decrements were not attenuated by 5-min treatment with phorbol ester but were attenuated by 90-min treatment. The present results suggest that the treatment which decreases protein kinase C activity shows a neuroprotective action against oxygen/glucose free-induced deficits of metabolic and synaptic activity in hippocampal slices.


Intravenous angiotensin II induces Fos-immunoreactivity in circumventricular organs of the lamina terminalis. Conscious rats were infused intravenously with either angiotensin II (30-55 pmol/kg/min), isotonic saline or phenylephrine for 2 h, then killed. Fos was identified by immunohistochemistry in the brains. Fos expression occurred in many neurons of the subfornical organ and organum vasculosum of the lamina terminalis (OVLT) with angiotensin infusion but not with isotonic NaCl or phenylephrine. Fos immunoreactivity was induced in cells in several medullary, hypothalamic and limbic structures with infusions of angiotensin II or phenylephrine at pressor doses. The results suggest that blood-borne angiotensin II at physiological levels causes angiotensin receptive neurons in the subfornical organ and OVLT to express Fos. Activation of baroreceptor pathways may also induce Fos expression at several other sites.


Redirection of the hypoglossal nerve to facial muscles alters central connectivity in human brainstem. Functional motor control requires perfect matching of central connectivity of motoneurones with their peripheral connections. However, it is not known to what extent central circuitry is influenced by target muscles, either during development or following a lesion. Surgical interventions aimed at restoring function following peripheral nerve lesions provide an opportunity for studying this interaction in the mature human nervous system. We have followed 8 patients in whom the hypoglossal nerve was anastomosed into a lesioned facial nerve, allowing voluntary contractions of the previously paralyzed muscles. We show that, in addition to replacing the facial neurons at peripheral synapses, a new short-latency trigemino-hypoglossal reflex, of the R1 blink reflex type, can be demonstrated in patients showing recovery, implying a sprouting of trigeminal neurons towards hypoglossal motoneurones, over a distance of at least 0.5 cm. These surprising results show an unexpected influence of the periphery in remodelling central connectivity in man.


Mild traumatic brain injury enhances muscarinic receptor-linked inositol phosphate production in rat hippocampus. Recent evidence suggests that muscarinic receptors play a role in the hippocampal hypersensitivity to imposed ischemia following mild traumatic brain injury (TBI). In rat hippocampal tissue, carbachol-stimulated inositol phosphate production was found to be enhanced by mild TBI, at 1 h post injury. This finding suggests that mild TBI may result in enhanced coupling between muscarinic receptors and phosphoinositide hydrolysis, which may contribute to post-traumatic hippocampal vulnerability to secondary ischemia.


Sexual dimorphisms in the soma size of neurons in the brain of whiptail lizards (Cnemidophorus species). Soma area was significantly larger in the anterior hypothalamus-preoptic area of male than female Cnemidophorus inornatus, and it was significantly larger in females than males in the ventromedial hypothalamus. These results parallel those on the volume of the brain areas in these animals, and therefore probably explain at least part of the dimorphisms seen in this sexually reproducing species. Soma size in parthenogenetic C. uniparens also parallels volume.


The progressive changes of neuronal activities of the nigral dopaminergic neurons upon withdrawal from continuous infusion of cocaine. Sensitivity of the nigral dopamine neurons to intravenous apomorphine was examined in rats pretreated with continuous cocaine or saline for two weeks. One day after withdrawal from pretreatment, a subsensitivity was observed while a supersensitivity was found on day 7, along with a significant increase in the baseline firing rates. In humans, an increased sensitivity of dopamine soma/dendritic autoreceptors may partly account for the symptomatology associated with the intermediate phase of withdrawal from cocaine binges.


Short latency excitation of upper cervical respiratory neurons by vagal stimulation in the rat. Extracellular recordings were made from 29 respiration-phased neurons in the upper cervical spinal cord (C1-C3) in nine anesthetized rats while ipsilateral and contralateral vagi were stimulated via platinum hook electrodes. Neuronal responses to vagal stimulation were recorded using peristimulus histograms. An accumulation of spikes with an average latency of 4.0 +/- 0.8 (S.D.) ms occurred in 11 cells after ipsilateral stimulation. These results indicate that there are fibers in the vagus which oligosynaptically excite respiratory neurons in the upper cervical spinal cord.


Activation of paraventricular neurosecretory cells by local osmotic stimulation of the median preoptic nucleus. Both electrical and local osmotic stimulation of the median preoptic nucleus (MnPO) predominantly produced excitation of paraventricular (PVN) neurosecretory cells in the rat. By contrast osmotic stimulation of the medial septal region was without effect, although electrical stimulation excited most cells. The results suggest that the MnPO is one of the osmosensitive sites controlling electrical activity of PVN neurosecretory cells.


Gamma-glutamyltaurine has potent and long-lasting antiepileptic action as demonstrated by intra-amygdaloid injection in amygdala-kindled rats. Intra-amygdaloid injections of gamma-glutamyltaurine, a recently identified brain dipeptide, strongly suppressed seizures in amygdala-kindled rats stimulated with intensities 10 or 50 microA above the generalized seizure triggering threshold (mean 82 microA). The suppressive effect persisted as long as 3 days. Taurine had relatively weak suppressive effects. Thus gamma-glutamyltaurine seems much more potent than taurine in the suppression of epileptic seizures when injected directly into the kindling site.


A continuing signal maintains NGF receptor expression in hypoglossal motor neurons after crush injury. Inhibition of axonal transport by vincristine applied to hypoglossal nerves 7 days after crush injury turns off the usual injured-induced expression of low affinity nerve growth factor receptor (p75NGFr). Vincristine applied proximal but not distal to the crush prevents p75NGFr induction. These results indicate that a continuing signal is axonally transported from the crush site that induces and maintains p75NGFr expression by injured motor neurons.


Visions of body and soul.

Visions of body and soul. Inspiration for the Sacred Mirrors emerged after I had a series of mystical experiences that caused me to redefine my view of consciousness and the self. I saw the body as not just a solid isolated object in a world of separate forms and existential anxiety, but more like a manifestation of primordial energy of awareness that was everywhere present.... I wanted my paintings to visually chart the spectrum of consciousness from material perception to spiritual insight, and to function, if possible, as symbolic portals to the mystical dimension.... The obvious way was to present a believable and almost hyper-real portrayal of the physical body and then seduce the viewer into the stranger mystical dimensions.


Magnetic resonance imaging of reconstructed knee ligaments. Reconstruction of knee ligaments is now a common orthopedic procedure. Patients are frequently referred for magnetic resonance imaging (MRI) after later reinjury, and the ability to recognize normal reconstructed knee ligaments is therefore becoming increasingly important. This pictorial essay demonstrates various reconstructions of the cruciate and the collateral ligaments, as well as several abnormalities of these ligaments.


Fetal cystic hygromas: further insights into their natural history. The authors report their experience with 17 cases of cystic hygroma diagnosed in utero over a period of 6 years and followed to early infancy. Attempts were made to determine which ultrasonographic features were significant in predicting the outcome of this condition. The intrauterine course of the 6 fetuses with a normal karyotype and the 11 fetuses with Turner's syndrome or another form of aneuploidy was analysed to determine whether the size of the hygroma or the presence of septation or nonimmune hydrops could be used to predict the eventual outcome of the pregnancy. An association between the presence of septation and outcome was not demonstrated, but there was a strong association between septation and aneuploidy. Septate lesions were present in 6 of the 10 fetuses with Turner's syndrome and only 2 of the 6 fetuses with a normal karyotype. In this series the most significant features indicating a favourable outcome were the size of the hygroma (no fetus in which the hygroma had a diameter greater than 6 cm survived) and the change in size from the time of diagnosis until 24 weeks' gestation. Of the three fetuses in which the hygroma did not regress by 24 weeks, two died in utero.


Ultrasonographic findings in the anterior segment of the eye obtained with a nondedicated unit. Many abnormalities of the anterior segment of the eye can be detected by ultrasonography (US), and associated anomalies of the posterior segment that are difficult to detect clinically may also be demonstrated by this modality. A total of 48 patients with ultrasonographically detectable abnormalities in the anterior segment were examined with real-time high-resolution US; 51 abnormalities were demonstrated. The most common problems were cataract (19 cases), intraocular lens implant (10), dislocated lens (9) and tumour (8). In addition, 23 abnormalities of the posterior segment of the eye were found. Six of the lesions in the posterior segment were obscured by those in the anterior segment and could be detected only by US.


Varicocele embolization through competent internal spermatic veins. Transvenous embolization has gained wide acceptance as a primary therapeutic technique in the management of varicocele. In most cases incompetence of the internal spermatic vein is the main cause of the disorder. In 18 of 165 patients treated with embolization, venography demonstrated competence of the internal spermatic vein; the varicocele was due to incompetence of some other anastomotic connection to the vein or the pampiniform plexus. The finding of valvular competence during embolization in a patient with clinical or ultrasonographic evidence of varicocele should not lead to termination of the procedure; instead, a concerted effort should be made to cross the valve to allow therapeutic embolization.


Metastatic neuroblastoma presenting as a mandibular mass. Neuroblastoma is the third most common type of cancer seen in children, after leukemia and tumours of the central nervous system. Although bony metastasis to the skull and the orbits has been well described, metastasis to the mandible is exceptional; 32 cases have been reported. Two more are presented here, along with a short review of the topic emphasizing the radiographic features and the differential diagnosis.


The computed tomographic appearance of subcutaneous nodules occurring in metastatic neuroblastoma. The authors report a case of subcutaneous nodules in a 2-month-old girl with metastatic neuroblastoma; the appearance of the nodules in computed tomography scans is described. Such nodules are sometimes overlooked by clinicians and radiologists, even though they almost always occur in disseminated disease. In patients with neuroblastoma and other neoplasms subcutaneous nodules may be an easily accessible source of samples for histopathologic examination.


Computed tomographic detection of skeletal muscle calcifications in rhabdomyolysis. The authors report a case of rhabdomyolysis with extensive calcification of the paravertebral muscles secondary to ingestion of desipramine hydrochloride, a tricyclic antidepressant. Computed tomography (CT) and isotope scanning were performed, and pathological confirmation of the condition was obtained. The extent of the calcification was probably due to the administration of supplementary calcium to correct hypocalcemia. The authors discuss the correlation between the CT and isotope scan findings.


Angiography of a bronchial carcinoid tumour. The author describes a patient in whom a bronchial carcinoid tumour was demonstrated preoperatively only by bronchial arteriography. The reported arteriographic characteristics of such a lesion include hypertrophy of the bronchial artery, a tumour blush and the apparent absence of venous drainage.


Hemorrhagic colitis caused by Escherichia coli O157:H7--unusual ultrasonographic and computed tomography findings. Hemorrhagic colitis due to Escherichia coli O157:H7 occurs sporadically but widely throughout North America. Radiographically this condition may mimic ischemic colitis, inflammatory bowel disease, acute appendicitis or appendiceal abscess. Correlation of radiologic and clinical findings is required to ensure diagnostic accuracy and avoid unnecessary surgical intervention.


Ultrasonography of foreign-body tenosynovitis. A patient presented with cellulitis of the hand 4 weeks after she was injured by sea urchin spines. Ultrasonography proved useful in identifying three small fragments of spine and suggested tenosynovitis. This method should be considered the imaging technique of choice for wounds of the hand when foreign bodies are suspected.


[Study in the anuran amphibian Xenopus laevis, some blood characteristics and nitrogen excretion based on changes in the water osmolarity]. The pH, the osmolality and the urea and ammonia concentrations in blood, as well as the net urea and ammonia excretions, were studied in the amphibian Xenopus laevis exposed for several weeks to increased osmotic pressure (OP) of the ambient water, as a result of the addition of either NaCl or mannitol to the water. The pH and the ammonia concentration of the blood were independent of the variations of the ambient osmolarity. On the contrary, the blood osmolality and its urea concentration increased markedly when the ambient OP was augmented. The increase of ambient OP by NaCl addition to the medium augmented the urea net excretion and slightly decreased the ammonia excretion. When the increase of ambient OP resulted from the addition of mannitol in the water, excretions of urea and ammonia became negligible.


[Taste thresholds and above-threshold responses to fructose solution in relation to diet in Callitrichidae primates]. Taste thresholds and consumption responses to above-threshold concentrations of fructose solutions were determined in eight callitrichid primate species using the "two-bottle preference test". Although taste thresholds are relatively similar across species, above-threshold responses may differ considerably between marmosets and tamarins. As fructose concentration increases, the rate of consumption increases less for most marmoset species (Cebuella and Callithrix spp.) than for Goeldi's monkey (Callimico) and tamarins (Saguinus and Leontopithecus spp.). It is proposed that distinct shapes of the curves illustrating these responses characterize species in terms of global taste system adaptations to different diets.


[Binocular coordination during reading]. Is there an effect on binocular coordination during reading of oculomotor imbalance (heterophoria, strabismus and inadequate convergence) and of functional lateral characteristics (eye preference and perceptually privileged visual laterality)? Recordings of the binocular eye-movements of ten-year-old children show that oculomotor imbalances occur most often among children whose left visual perceptual channel is privileged, and that these subjects can present optomotor dissociation and manifest lack of motor coordination. Close binocular motor coordination is far from being the norm in reading. The faster reader displays saccades of differing spatial amplitude and the slower reader an oculomotor hyperactivity, especially during fixations. The recording of binocular movements in reading appears to be an excellent means of diagnosing difficulties related to visual laterality and to problems associated with oculomotor imbalance.


[Stimulation of the prostate growth in rats by milk casomorphins]. Thymidine kinase activity of the ventral prostate from adult rats could be stimulated by administration to the animal of casomorphin or casomorphin (morphiceptin). On the other hand addition of both drugs to the culture medium of prostatic cells from immature rats enhanced the cells growth. In both cases, morphiceptin was more efficient than casomorphin. These results suggest than casomorphins have other properties than their morphinomimetic effects previously described.


[Contribution of "bobbed" phenotype to the magnification of ribosomal DNA in Drosophila melanogaster]. Phenotype and magnification of two bobbed mutations allelic to the XNO region were studied at various temperatures. Results showed that magnification increases with increased severity of bobbed phenotype in that the reversion of the bbT6 allele is the same at high and low temperature whereas the thermosensitive bbP5 allele shows increased reversion at high temperature. Temperature shift experiments carried out during the development of premagnified males show that magnification which is followed by selection stage occurs during embryogenesis.


[Molecular and cellular action of butyrate]. Butyrate has a dramatic effect on transformed cells in culture. This effect disappears as soon as butyrate is removed from the medium. The other short chain fatty acids are much less effective. Butyrate produces an arrest of cell proliferation at the early G1 phase of the cell cycle. The effect is very general and may be used for cell growth synchronization. This compound increases the expression of the c-fos oncogene and inhibits the expression of c-myc in all phases of the cell cycle. Butyrate modulates the expression of several genes. In general it induces the expression of markers of cell differentiation. Many studies have been devoted to hemoglobin synthesis which is induced in erythroleukemia cells. In general it induces the synthesis of embryonic and of fetal hemoglobin, and delays and even suppresses the switch to adult hemoglobin, which could be useful for the treatment of sickle cell anemia and beta thalassemia. This effect of butyrate seems to require specific DNA regulatory sequences. Butyrate induces the synthesis of alkaline phosphatase, placental and intestinal isozymes, especially in cells where these syntheses are ectopic. It has the same effect on peptidic hormone syntheses and also on receptors of thyroid hormone and insulin. It stimulates their synthesis in cells which are poor in receptor and inhibits the synthesis in cells which have high amounts of these receptors. The use of antibiotics and of the run on method strongly suggest that butyrate acts at the transcriptional level. Butyrate inhibits the induction of proteins, including enzymes, by steroid hormones as has been shown for the induction of tyrosine aminotransferase by glucocorticoids, of ovalbumin and transferrin by estradiol in chick oviduct. Butyrate strongly alters cell morphology, usually it produces an enlargement of the cells with formation of protrusions. In HTC cells alteration of nucleoli and of the nuclear shape are observed. All these alterations are reversible and the cells recover the normal morphology upon removal of butyrate. These alterations result at least partly from modifications of the cytoskeleton: induction of vimentin and cytokeratin, formation of microfilaments, of microtubules and of actin fibers. The external matrix is also modified, as are the cell surface glycoproteins, and gangliosides. Most of these alterations are consistent with the loss of transformation characteristics of the cell. The mechanism of action of butyrate has been studied by many authors. It has been well established that butyrate induces an hyperacetylation of histones by inhibiting histone deacetylases, which is consistent with its stimulatory effect on gene expression.4+ and would require transacting proteins. The use of butyrate in therapeutics would require the synthesis of new molecules including butyrate but more active and metabolized at a slower rate. Several such molecules have been synthesized: monobutyrate 3 (or 6) monoacetate glucose, pivalyloxymethyl-butyrate. The use of such molecules in human therapeutics has been suggested, especially in hematology (sickle cell anemia, beta thalassemia) and in cancerology.


[Demonstration of cerebral lateralisation disorder in autistic children: study of auditory reactivity by transcranial pulsed Doppler]. Transcranial Doppler Ultrasonographic recordings of the middle cerebral arteries were performed on children with autistic behavior (AUT), compared to retarded children without autistic behavior (NON-AUT) and normal children (NOR). Blood flow measurements (resistance index) were performed at rest and during auditory stimulations. Compared to NOR and NON-AUT, significant differences of the resistance index were found in AUT on the left side, thus suggesting differences in metabolic mechanisms evoked by auditory stimulations. This result confirms the hypothesis of abnormal development of cerebral lateralization in autism.


[Relation between the change of slope of heart rate and second lactic and ventilatory thresholds in muscular exercise with large load]. The time-course of heart rate, blood lactate, and ventilatory gas exchange was studied during an incremental exercise test on cycloergometer in order to ascertain whether heart rate deflection occurred at the same load as the second lactate S[La]2) and ventilatory (SV2) thresholds. Twelve moderately trained subjects, 22 to 30 years old, participated in the study. The initial power setting was 30 W for 3 min with successive increases of 30 W every min except at the end of the test where the increase was reduced to 20 and 10 W.min-1. Ventilatory flow (VE), oxygen uptake (VO2), carbon dioxide production (VCO2, ventilatory equivalents of O2 (EO2 = VE/VO2) and CO2 (ECO2 = VE/VCO2), and heart rate (HR) were determined during the last 20 s of every min. Venous blood samples were drawn at the end of each stage of effort and analyzed enzymatically for lactate concentration ([La]). The HR deflection, S[La]2, and SV2 were represented graphically by two investigators using a double blind procedure. Following the method proposed by Conconi et al. 1982, the deflection in HR was considered to begin at the point beyond which the increase in work intensity exceeded the increase in HR and the linearity of the work rate/HR relationship was lost. S[La]2 corresponded to the second breaking point of the lactate time-course curve (onset of blood lactate accumulation) and SV2 was identified at the second breaking point in the increase in VE and ventilatory equivalent for O2 uptake accompanied by a concomitant increase in ventilatory equivalent for CO2 output. We observed that the deflection point in HR was present only in 7 subjects. The work load, VO2, HR, and [La] levels at which heart rate departed from linearity did not differ significantly from those determined with S[La]2 ans SV2. The VO2 and HR values at HR deflection point were significantly correlated with those measured at S[La]2 and SV2. It is concluded that deflection in heart rate does not always occur, and when it does, it coincides with the second lactate and ventilatory gas exchange thresholds. It can thus be used for the determination of optimal intensity for individualized aerobic training.


[Detection of the deletion of interferon-alpha and beta genes in lymphoblastoid cells by PCR]. The HuIFN-alpha and beta genes were examined by the PCR method in the 11 human lymphoblastoid cell lines. The results showed that the homozygous deletion of HuIFN-alpha and beta genes was detected in 5 of 11 cell lines and in 5 of 11 cell lines, respectively. The deletions of both the HuIFN-alpha and beta genes were observed in 4 of 11 cell lines. One T cell leukemia cell line deleted only HuIFN-alpha gene, while the other T cell leukemia line deleted only HuIFN-beta gene. This suggests that the deletions of HuIFN-alpha and beta genes may be related the development of leukemia or lymphoma.


[Current data on the exploration and the evaluation of clinical pain]. Pain is a complex, multidimensional and multifactorial neuropsychological phenomenon with sensory-discriminative, affective, cognitive and behavioral components. Issues on pain assessment are related to the objective evaluation of a subjective phenomenon. Different levels of evaluation are to be considered. Some methods like visual analogue scale, numerical scale and verbal permit a global pain estimation. The aim of other methods like the McGill Pain Questionnaire is a quantitative and qualitative evaluation of the sensory and affective pain components. The measure of objective behavioral changes is an interesting approach, but at the present time there is no valid, simple and commonly used method. There is also a need for methods permitting a better exploration of a pain, and in particular a selective evaluation of organic and functional factors. The limits of psychological factors evaluation are reported.


[Targeting of tumor cells by low density lipoproteins: principle and use of ellipticin derivatives]. Cells acquire cholesterol via de novo synthesis and high affinity receptor-mediated uptake of low-density lipoprotein (LDL). Some tumor tissues display increased receptor-mediated uptake of LDL as compared with the corresponding normal tissues. This increased LDL receptor activity is unexplained: a high cholesterol demand for cell growth or a mechanism directly linked to cell transformation. LDL has therefore been proposed as a potential carrier for chemotherapeutic agents. Various methods have been used to incorporate antineoplastic lipophilic drugs into LDL. The resultant drug-LDL complexes have been shown to be cytotoxic towards tumor cells in vitro, via the LDL receptor dependent pathway. However little is now on the in vivo fate of this complex. We described the incorporation of lipophilic derivatives of ellipticine into LDL by a fusion or facilitated transfer technique between drug containing microemulsions and LDL. The drug-LDL complex expressed similar metabolic activity, in vitro and in vivo, than native LDL. Initial experiments with melanoma B16 tumor-bearing mice suggest that LDL may be a potential drug carrier in the treatment of malignant diseases. The knowledge of the molecular mechanism of the expression of the LDL receptor in tumor cells and the ability to downregulate the LDL receptor in the normal tissues, will define the application field of this targeting approach.


[Antitumor photochemotherapy: biochemical bases, therapeutic uses and perspectives]. The photodynamic therapy of tumors (PDT) is a recent and promising technique for the treatment of tumors which can be reached by the light (directly or by endoscopic illumination). Excellent results are now obtained with hematoporphyrin derivatives such as Photofrin II, provided the concerned tumors are small and well delimited. Porphyrins are transported in blood mainly by lipoproteins, and the low density lipoprotein (LDL) receptor-mediated pathway is probably one of the important factors involved in the selective accumulation of porphyrins by tumor tissues, as cancer cells generally express much more LDL receptors than normal cells. In the present paper, after a brief presentation of the biochemical basis of the light-dependent cytotoxicity of porphyrins, we shall examine the role of lipoproteins, especially LDL, in the transport and the cellular uptake of these compounds. We shall also present recent approaches for the improvement of the PDT efficiency.


A classification of residential neighbourhoods (ACORN) in relation to dental health and dental health behaviours. Five-year-old children in two district health authorities in the North Western Region of England were examined during 1989-90. Questionnaires were issued to parents to determine whether dental health and related behaviours were associated with socio-economic status. Parents of 1858 children in Salford (response rate = 78 per cent) and 1691 in Trafford (response rate = 81 per cent) returned the questionnaires. Their replies were analysed by dividing the children into a hierarchy according to a classification of residential neighbourhood (ACORN). Significantly fewer in the highest of three Divisions in both districts had suffered from toothache and had undergone a general anaesthetic to have teeth extracted. They were also more likely to have had their teeth brushed with toothpaste by their first birthday and to have visited the dentist by their second. Because ACORN had detected these differences in dental health related behaviour it was possible to identify localities towards which dental health promotion activities can be directed.


Loss of the first permanent molar and caries experience of adjacent teeth. The caries experience of the occlusal and distal surfaces of the second premolars and the occlusal and mesial surfaces of the second permanent molars was examined in four groups of subjects aged 19-20 years. Group 1 comprised subjects with first permanent molars present, Group 2 subjects with early loss of the first permanent molar (before the age of 11-12 years), Group 3 subjects with late loss of the first permanent molar (after 11-12 years but before 15-16 years) and Group 4 included a combination of Group 2 and Group 3. Loss of the first permanent molar was associated with increased caries or restorations in the occlusal surfaces of adjacent teeth, but reduced caries or restorations in the proximal surfaces of adjacent teeth. Early loss of the first molar was associated with significantly greater caries or restoration experience in proximal surfaces than late loss, but no difference was detected for occlusal surfaces.


The prevalence of developmental defects of enamel in 15-16-year-old children residing in three districts (natural fluoride, adjusted fluoride, low fluoride) in the north east of England. Developmental defects of enamel were assessed in 15-year-old children born and continuously resident in three communities in the north east of England. In naturally fluoridated Hartlepool (F = 1.0-1.3 ppm), artificially fluoridated Newcastle (F = 1.0 ppm) and non-fluoridated Middlesbrough (F < 0.2 ppm) 361, 356 and 376 children respectively were examined. Conventional clinical recording and a photographic technique where colour slides are assessed at random were used and compared. Scoring in both assessments was done by using a modified version of both the Murray and Shaw index and the developmental defects of enamel index. In the clinical assessment more white lines and diffuse opacities were found in the fluoridated areas than in the non-fluoridated area. More opacities were recorded using the photographic assessment than with the clinical assessment, but a similar trend of an increased prevalence of white lines and diffuse opacities was observed using the photographic method. Overall, there was only a small increase in the prevalence of milder forms of enamel defects in fluoridated compared with non-fluoridated areas.


A programme of preventive dentistry in field conditions carried out in Glasgow, Scotland. A caries-preventive regime comprising fluoride supplementation in age-related doses, three monthly acid-phosphate-fluoride applications, fissure sealing of deciduous and first permanent molars and chair-side dental health education, had been proved cost-effective in a single health centre setting. It was therefore expanded to a community-wide project in the Greater Glasgow area. This study describes the coverage achieved by the scheme, the demographic details of the children involved, and measured the dental health benefits accrued by the participants. The children received an annual dental examination and, to assess the effects of the programme, the records of 310 subjects who had attended three annual examinations were used. The deft and defs reductions ranged from 60 to 6.5 per cent and 58.8 to 9.6 per cent respectively, and equivalent DMFT and DMFS reductions ranged from 11.1 to 0 per cent, and 33.3 to 16.7 per cent respectively. Previously, deft reductions of 63.7 to 86.2 per cent, and defs reductions of 77.6 to 92.6 per cent had been reported (Stephen et al., 1983). In contrast, the corresponding deft and defs reductions achieved in this project were only up to 16.7 and 9.6 per cent respectively. The programme was most beneficial for children who had reached the age of three years after two year's participation in the scheme. The dental health benefits accrued by those receiving the preventive programme appear to be inversely proportional to its size. Therefore it represents an important example of the reduction of a preventive agents' effectiveness when used under field conditions, as opposed to those of controlled clinical trials.


A comparison between commercial kits and conventional methods for enumeration of salivary mutans streptococci and lactobacilli. Mutans streptococci (ms) and lactobacilli levels were determined by conventional and commercial dip-slide methods in three groups of young subjects, aged 5-6 years (93 subjects), 12-13 years (78 subjects) and 18-20 years (81 subjects). Using the same paraffin-stimulated saliva samples, ms and lactobacilli were estimated by conventional viable counts on modified mitis-salivarius agar (MSB) and Rogosa agar plates, and by inoculation of Dentocult SM and Dentocult LB dip-slides (Orion Diagnostica, Finland). The salivary ms and lactobacilli counts obtained from conventional agar plates were significantly correlated (P < 0.0001) with the dip-slide estimates of these organisms (Kendal Tau = 0.56, 0.71 respectively). Subjects in Group 2 showed the highest proportion (77 per cent) of individuals with salivary ms levels above 2.5 x 10(5) cfu/ml saliva; 99 per cent of that group had detectable levels of lactobacilli. Significantly different median salivary ms and lactobacilli levels were demonstrated between all groups except for lactobacilli levels between Groups 2 and 3. These dip-slide tests provided suitable and simple methods for screening salivary lactobacilli and ms levels which may have a useful role in the assessment of caries risk.


A multivariate model to predict caries increment in Montreal children aged 5 years. A study was carried out in Montreal (Canada) to predict caries development over the period of one year in primary teeth of kindergarten children (mean age 5 years 8 months +/- 4 months) living in a non-fluoridated area. The 302 children were examined at school on two occasions, one year apart. At the first examination selected predictors were collected: caries experience, salivary S. mutans and lactobacilli, buffer capacity, debris index, parents' education, fluoride consumption and family structure (one or two parents). Regression analysis was performed to select the significant factors. A total of 143 children developed new caries over the study period; the mean increment for the whole group was 2.1 dmfs. Sensitivity (Sn) and specificity (Sp) were calculated for each predictor and for the final model. The best model comprised only two factors, caries experience and lactobacillus. This could identify 81.8 per cent of children who would develop new caries during the next 12 months (Sn) and 77.4 per cent of those who would not (Sp). Among the single predictors caries experience alone reached 78.3 per cent for sensitivity and 77.4 per cent for specificity. None of the other predictors, except parents' education, was very good at predicting caries increment over one year.


Factors affecting dental attendance among school leavers and young workers in Greater Manchester. The aim of this study was to investigate those factors which could influence adolescents in their dental attendance habits. Discussion groups were formed with school pupils in their final school year and with Youth Training Scheme trainees who had been working for six months or more. Fourteen discussions, involving 97 adolescents, were carried out and recorded on tape. Analysis of these tapes permitted comparison of the responses of the school leavers and the trainees which revealed some recurring themes. No major differences were found between the adolescents in their views on dental attendance before and after leaving school. Many respondents said that they had been able to decide for themselves about going to the dentist since they were 12, 13 or 14 years old, well before school leaving time. A low perception of need and a high level of confidence in self-care were widely reported and these tended to reduce the likelihood of attendance. The desire to maintain or produce a good dental appearance was frequently given as the main motive for attending the dentist.


Dental attendance patterns among mothers and their children in an area of social deprivation. Dental attendance behaviour was recorded for 358 children aged 5-6 and 10-11 years and their mothers living in a socially deprived area of south Manchester. Information obtained by questionnaire was verified by the local dentists concerned. Forty-four per cent of mothers and 61 per cent of children had attended a dentist in the previous 12 months. The mothers' attendance was a good predictor of children's attendance, although a substantial proportion of mothers who did not attend the dentist themselves did ensure the attendance of their children.


Factors determining satisfaction with dental care. The objective of the present study was to study satisfaction with previous dental care in a Swedish population aged 45-69 years. The relationship between a number of factors and satisfaction with care was studied, and differences between people attending private and public dental clinics were examined. The data were collected by an anonymous questionnaire. A multivariate analysis showed that reported satisfaction with previous dental care depended primarily on three factors; treatment by the dentist of choice, chewing ability and contentment with their own dental conditions.


Assessment of bone formation by biochemical markers in metabolic bone disease: separation between osteoblastic activity at the cell and tissue level. In this study , serum levels of classical serum markers of bone formation [carboxyterminal propeptide of procollagen type I (S-PICP), bone Gla protein (S-BGP)], and total alkaline phosphatase (S-AP)) were related to the calcium kinetic index of whole skeletal mineralization rate (m) by regression analysis in a variety of metabolic bone diseases. For each disease, the regression coefficient (r) as well as the fraction: standard error of estimate/mean dependent variable (SEE/Y) were determined. In a group of 19 normals, only the regression of S-PICP on m reached significance (r = 0.53, P < 0.02, SEE/Y = 0.44), whereas regressions of S-AP and S-BGP on m were nonsignificant. In a pooled material of high- and low-turnover bone diseases without mineralization defects or spinal fracture [myxedema, thyrotoxicosis, and primary hyperparathyroidism (n = 48)], a highly significant positive regression of S-PICP on m was demonstrable (r = 0.50, SEE/Y = 0.63, P < 0.001). The regression coefficients obtained for S-BGP and S-AP were 0.74 (P < 0.001, SEE/Y = 0.41) and 0.42 (P < 0.01, SEE/Y = 0.55), respectively. When analyzing individual diseases in this group, significant differences among the three markers were detectable. In a group of 52 osteoporotics, S-PICP correlated significantly to m (r = 0.49, P < 0.001, SEE/Y = 0.50). Corresponding r-values for S-BGP and S-AP were 0.21 (NS) and 0.48 (P < 0.001, SEE/Y = 0.61), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)


Serum intact parathyroid hormone levels in elderly Chinese females with hip fracture. Serum intact parathyroid hormone (PTH), 25 hydroxyvitamin D(25OHD), 1,25 dihydroxyvitamin D (1,25(OH)2D), albumin, and ionized calcium were measured in 61 Chinese female patients with hip fracture and 61 control subjects. Hip fracture patients had low albumin, ionized calcium, and 250HD levels. Serum PTH and 1,25(OH)2D values were not different between the two groups. We conclude that although 250HD level in hip fracture patients is low, there is no evidence of secondary hyperparathyroidism, suggesting that the low 250HD levels may be a secondary phenomenon in response to the fracture.


The relationship between ultrasound and densitometric measurements of bone mass at the calcaneus in women. Broadband ultrasound attenuation (BUA) of the calcaneus predicts axial density in women and is decreased in women who sustain hip fractures. To determine the relationship between ultrasonic and densitometric assessments of bone mass at the same site, BUA and velocity of sound (VOS) were correlated with bone density as measured by dual energy x-ray absorptiometry (DXA) at the calcaneus in 64 Caucasian women aged 35-83 years. BUA, VOS, and bone density in these women decreased annually as a function of age by 1.0%, 0.3%, and 0.9%, respectively. Holding age, years since menopause, height and weight constant, BUA correlated with VOS (r = 0.74, P < 0.001), and calcaneal density correlated with BUA (r = 0.73, P < 0.001) and with VOS (r = 0.66, P < 0.01). The results indicate that both BUA and VOS measurements reflect density at the calcaneus, but suggest that they measure properties of bone other than density and different from each other. The assessment of these additional properties may be useful in the prediction of fracture risk.


Caffeine has the capacity to stimulate calcium release in organ culture of neonatal mouse calvaria. In view of the possible association between ingestion of caffeine (a constituent of coffee, tea, and several beverages) and osteoporosis, we have studied the effect of caffeine on bone resorption in vitro. Caffeine caused a dose-dependent increase of the spontaneous release of 45Ca from neonatal mouse calvarial bones. The effect of caffeine was less pronounced than that of parathyroid hormone (PTH), but of the same magnitude as that of theophylline, a structurally related methylxanthine. The enhancement of 45Ca release induced by caffeine and PTH was observed in 5 days culture. In 2 days culture, however, only PTH stimulated mineral mobilization. The delayed stimulatory effect of caffeine in long-term cultures was abolished by indomethacin and flurbiprofen. In indomethacin-treated bones, however, caffeine potentiated the stimulatory effect on 45Ca release induced by choleratoxin and forskolin. In contrast, caffeine did not potentiate 45Ca release stimulated by PTH. These data show that caffeine can stimulate calcium release from bone in vitro and that this effect is due to potentiation of a stimulatory action of a bone resorptive agonist acting via the adenylate cyclase-cyclic AMP system.


Modulation of matrix vesicle enzyme activity and phosphatidylserine content by ceramic implant materials during endosteal bone healing. This study examined effects of bone bonding and nonbonding implants on parameters associated with matrix vesicle-mediated primary bone formation, matrix vesicle alkaline phosphatase and phospholipase A2 specific activities, and phosphatidylserine content. Tibia marrow ablation followed by implantation of KG-Cera, Mina 13 (bonding), KGy-213, or M 8/1 (nonbonding) was used as the experimental model. Postsurgery, matrix vesicle-enriched microsomes (MVEM) were isolated from implanted and contralateral limbs. MVEM alkaline phosphatase and phospholipase A2 were stimulated adjacent to bonding implants with similar, though reduced, effects contralaterally. Alkaline phosphatase exhibited slight stimulation in nonbonding tissue; phospholipase A2 was inhibited or unchanged in treated and contralateral limbs. Phosphatidylserine content of MVEM was differentially affected by the implant materials. Thus, MVEM are modulated by implant materials locally and systemically. The data demonstrate that the model is a biologically relevant diagnostic for assessing the tissue/implant interface, primary calcification is affected by implant materials, and implant-specific effects are detected in the contralateral unimplanted limb.


Affinity of bone sialoprotein and several other bone and dentin acidic proteins to collagen fibrils. Bone and dentin contain several kinds of mineral-binding proteins and cell-attachment proteins. The authors examined the affinity of these proteins to type I collagen, a major matrix protein of the tissue. Bone sialoprotein (BSP), bone Gla protein (BGP), bone small proteoglycan II (PG II), osteonectin (ON), and dentin phosphophoryn (DPP) were labeled with fluorescein isothiocyanate and incubated with reconstituted type I collagen fibril. DPP, BGP, BSP, and PG II were absorbed significantly to the collagen fibril at physiological ionic strength with dissociation constants of 10(-6)-10(-7) M. BSP and PG II enhanced the fibrillogenesis of collagen. These acidic proteins can affect the surface properties of collagen fibril, and BSP, having the cell-attachment sequence Arg-Gly-Asp, possibly mediates interaction between collagen fibril and cells.


FT-IR microscopic mappings of early mineralization in chick limb bud mesenchymal cell cultures. Chick limb bud mesenchymal cells differentiate into chondrocytes and form a cartilaginous matrix in culture. In this study, the mineral formed in different areas within cultures supplemented with 4 mM inorganic phosphate, or 2.5, 5.0, and 10 mM beta-glycerophosphate (beta GP), was characterized by Fourier-transform infrared (FT-IR) microscopy. The relative mineral-to-matrix ratios, and distribution of crystal sizes at specific locations throughout the matrix were measured from day 14 to day 30. The only mineral phase detected was a poorly crystalline apatite. Cultures receiving 4 mM inorganic phosphate had smaller crystals which were less randomly distributed around the cartilage nodules than those in the beta GP-treated cultures. beta GP-induced mineral consisted of larger, more perfect apatite crystals. In cultures receiving 5 or 10 mM beta GP, the relative mineral-to-matrix ratios (calculated from the integrated intensities of the phosphate and amide I bands, respectively) were higher than in the cultures with 4 mM inorganic phosphate or in the in vivo calcified chick cartilage.


Toxicity and pharmacokinetics of intravitreally injected ciprofloxacin in rabbit eyes. To assess the toxicity of intraocular injection of ciprofloxacin, 22 New Zealand white rabbits received midvitreal injections of 100, 200, 400, 800 or 3200 micrograms of ciprofloxacin in 0.1 mL of distilled water (39 eyes) or 0.1 mL of distilled water only (5 eyes). The ocular pharmacokinetics of intravitreally injected ciprofloxacin was determined by aqueous humour and vitreous sampling 1, 2, 4, 8, 12, 18 or 24 hours after midvitreal injection of 100 micrograms of the drug in one eye each of 25 New Zealand white rabbits. The samples were analysed by means of a disc diffusion bioassay. No ocular damage was noted on ophthalmoscopy at any of the concentrations tested. Histologic study showed mild, transient vacuolation of the nerve-fibre layer in all eyes, including the control eyes, 2 hours after injection; at 24 hours no vacuolation was evident except at concentrations of 800 and 3200 micrograms, at which plexiform layer damage was evident. Peak aqueous and vitreous levels of ciprofloxacin were obtained at 1 hour (0.59 and 27.26 micrograms/mL respectively); the vitreous level fell to below 1.0 micrograms/mL 12 hours after injection. We conclude that intravitreally injected ciprofloxacin may be a safe and useful antibiotic in the treatment of aminoglycoside-resistant bacterial endophthalmitis.


Ethmoidectomy decompression for the treatment of Graves' optic neuropathy. When orbital decompression becomes necessary in Graves' optic neuropathy, medial wall decompression is a necessary component of the decompression procedure. The ethmoidectomy approach allows more direct visualization of the posterior ethmoids and sphenoids to effect maximum decompression. This is particularly important in cases in which computed tomography shows the medial rectus muscle to be enlarged posteriorly in the orbit. The procedure provides excellent visualization of the medial rectus. As with any medial wall decompression procedure, postoperative restriction of horizontal motility is a frequent complication, often necessitating more than one subsequent operation. The authors describe their experience with the procedure in 25 patients with Graves' optic neuropathy.


Automated detection and quantification of venous beading using Fourier analysis. Venous beading associated with diabetic retinopathy is currently assessed by means of subjective comparison to standard photographs from the modified Airlie House classification scheme. We describe a computerized grading scheme for venous beading. The algorithm, based on Fourier analysis of vessel width measurements, generates a venous beading index (VBI) for digitized colour fundus photographs. Colour photographs of local vessel segments about 1200 microns in length were evaluated by experienced graders. A comparison between the VBI and subjective grading showed good agreement. The mean VBI values across the four levels of clinical grading were significantly different (p = 0.000). Multiple comparison testing indicated that the VBI was able to significantly differentiate between all four categories except the "questionable" (grade 1) category (p < 0.05). We also found that progression of venous beading can be followed with the VBI. The results indicate that further development of automated grading of venous beading is warranted.


Collagen shields: efficacy, safety and comfort in the treatment of human traumatic corneal abrasion and effect on vision in healthy eyes. To study the efficacy, safety and comfort of porcine collagen shields in the treatment of traumatic corneal abrasion, patients with corneal abrasions that had occurred within 24 hours before examination were treated with either a collagen shield (18 patients) or tight patching (12 patients). There was no significant difference in the rate of healing or the proportion of corneas healed between the two groups. The collagen shield was significantly more comfortable than the patch (p < 0.05). After 1 hour of wear the collagen shield allowed useful vision (mean 20/100) in nine healthy volunteer subjects. Collagen shields may be of benefit in carefully selected cases of traumatic corneal abrasion.


Role of tear secretory IgA in hard contact lens-related changes in the tarsal conjunctiva. The role of tear secretory IgA in contact lens-related conjunctival changes was investigated in 40 subjects (80 eyes) who wore polymethyl methacrylate (PMMA) contact lenses and 10 subjects (20 eyes) who did not wear contact lenses. The eyes in the contact lens group had significantly higher tear IgA levels than the control eyes (p < 0.05). We were not able to demonstrate a relation between increased IgA levels and the presence of symptoms or duration of contact lens wear. Increased IgA levels were correlated to papilla formation in the contact lens group. A rise in tear IgA levels seems to be the first abnormal change related to papilla formation in patients who wear PMMA contact lenses.


Cyclosporine in the treatment of nonmicrobial inflammatory ophthalmic disease. Eighteen patients with severe, progressive nonmicrobial inflammatory ophthalmic disease (including five with intermediate uveitis, four with sympathetic ophthalmia and three with serpiginous choroiditis) that had not responded to conventional therapy were treated with cyclosporine. Three of the four patients with sympathetic ophthalmia responded quickly and maximally, and the fourth showed partial improvement. One patient, with several corneal graft failures in the right eye, started cyclosporine therapy after undergoing left corneal transplantation; at the last follow-up visit the graft had been clear for almost 3 years. The response was inconsistent in patients with other types of eye disease. In general, the drug was well tolerated; however, two patients stopped treatment because of unpleasant side effects. No serious or irreversible complications developed. The results suggest that cyclosporine therapy is useful in the treatment of sympathetic ophthalmia and in high-risk corneal transplantation.


Ocular findings and visual evoked potential response in the Prader-Willi syndrome. It has recently been suggested that aberrant misrouting of retino-geniculate-cortical (RGC) projections, a finding previously noted only in albinism, may be an additional feature of the Prader-Willi syndrome. To determine the prevalence of ocular abnormalities in patients with the syndrome and to look for evidence of misrouted RGC projections by means of testing of the pattern-onset visual evoked potential (VEP) response, we examined 12 patients with Prader-Willi syndrome, 8 albino subjects and 5 healthy control subjects. Ocular findings in the first group included telecanthus (in five subjects), strabismus, nystagmus, foveal hypoplasia, visual field defects and cataract. However, the VEP asymmetry typically seen in albinism was not noted in any of the patients with Prader-Willi syndrome. Our findings do not support previous claims of abnormal optic nerve fibre decussation in Prader-Willi syndrome.


Drug-induced fatal aplastic anemia following cataract surgery. Aplastic anemia attributed to medications used in ophthalmology is rare. We report a fatal case that developed in a 73-year-old woman 7 weeks after cataract extraction performed under local anesthesia. Postoperative medications included a chloramphenicol-containing ointment, flurbiprofen sodium drops, prednisone acetate drops and orally given acetazolamide. It was felt that the aplastic anemia was related to therapy with chloramphenicol or acetazolamide or both. We recommend that the course of prophylactic antibacterial therapy after intraocular surgery be kept short, regardless of the preparation used. We urge caution in the choice and use of drugs known to be associated with aplastic anemia and recommend close monitoring of the hemogram.


Influence of low-flow infusion and magnesium on tissue necrosis during regional ischemia in the canine myocardium. Passive intracoronary perfusion of therapeutic agents has been used in the clinical setting to attenuate the effects of brief episodes of myocardial ischemia. The objective of this study was to assess the effects of low-flow coronary infusion with or without Mg2+ on tissue necrosis and cardiac hemodynamics after prolonged regional ischemia. In 33 anesthetized dogs (5 excluded during study), the left anterior descending coronary artery was occluded for 6 h. Dogs were assigned to three groups: the first group (n = 8) was subjected to 6 h coronary occlusion without low-flow perfusion (controls), the second group (n = 10) received a low-flow coronary infusion of Ringer's lactate (Mg(2+)-free), and the third group (n = 10) received a low-flow coronary infusion of Ringer's lactate plus Mg2+ sulfate (15 mM). Tissue necrosis was evaluated using tetrazolium staining and was normalized to the principal baseline predictors of infarct size including anatomic risk zone (microsphere autoradiography) and coronary collateral flow. In control hearts, infarct size comprised 51.1 +/- 4.1% of the risk zone (40.8 +/- 5.1% left ventricular cross-sectional area (LV)). In the Mg(2+)-free and Mg2+ groups, risk zone size was 17.3 +/- 2.2 and 16.8 +/- 1.8% LV (p < 0.05 vs. controls), while infarct size was 23.1 +/- 3.1 and 24.9 +/- 8.1% (p < 0.05 vs. controls), respectively. Coronary collateral flow in the endocardium was similar for all of the experimental groups; however, hearts subjected to ischemia with low-flow perfusion of Ringer's lactate demonstrated significantly higher epicardial coronary collateral flow levels compared with controls.(ABSTRACT TRUNCATED AT 250 WORDS)


Renal adrenergic receptors: localization of [125I]prazosin binding sites along the microdissected rat nephron. Norepinephrine stimulates renal tubular sodium reabsorption, probably through an alpha 1-adrenoceptor-mediated mechanism. Although the distribution of alpha 1-adrenoceptors in the kidney has been studied with autoradiography, the precise location of these receptors in isolated nephron segments is unclear. Using a microassay we determined the specific binding of [125I]iodoarylazidoprazosin ([125I]prazosin), a high specific radioactivity analog of the selective alpha 1-antagonist prazosin, to microdissected glomeruli and tubule segments. Specific binding of [125I]prazosin (3 nM) in the proximal convoluted tubule was time- and concentration-dependent, saturable, and reversible. In this segment the apparent KD by association and dissociation rate constants of [125I]prazosin binding was 0.47 nM, and the maximum receptor density was approximately 0.19 fmol/mm, or 720 fmol/mg protein. Binding specificity was verified in competition studies with excess (3 microM) unlabeled prazosin and probes for alpha 2- (yohimbine), beta- (propranolol), dopamine1- (SCH23390), and dopamine2- (S-sulpiride) receptors. [125I]Prazosin binding was inhibited significantly only by unlabeled prazosin. Mapping of prazosin binding along the nephron revealed that the highest density was in the proximal convoluted tubule, followed by the proximal straight tubule. Lesser binding was found in the thick ascending limb and in the distal convoluted tubule, whereas in the cortical and outer medullary collecting duct and in glomeruli, binding was not significantly different from zero.(ABSTRACT TRUNCATED AT 250 WORDS)


Catecholamine-induced changes in vascular capacitance and sympathetic nerve activity in dogs. The effects of three catecholamines, dopamine, epinephrine, and dobutamine, on the systemic circulation, especially on systemic vascular capacitance, were studied using cardiopulmonary bypass in dogs anesthetized with pentobarbital. Venous outflow was divided into three compartments: splanchnic, renal, and other; changes in systemic blood volume (SBV) were calculated from the changes in total venous outflow. To examine the contribution of sympathetic discharge to these vascular responses, sympathetic efferent nerve activity (SENA) from the ventral ansa subclavian nerve was recorded simultaneously. Experiments were done under three conditions: control, after baroreceptor deafferentation, and after hexamethonium injection with low and high doses of each catecholamine. During control and after baroreceptor deafferentation, dopamine- and epinephrine-induced changes in SBV were less than those after hexamethonium, and not significant except with low dose epinephrine. After hexamethonium, dopamine (200 micrograms/kg), epinephrine (10 micrograms/kg), and dobutamine (100 micrograms/kg) reduced SBV by 10.6 +/- 3.4, 13.1 +/- 1.7, and 1.9 +/- 0.3 mL/kg, respectively. Splanchnic outflow increased significantly with dopamine and epinephrine after hexamethonium. High dose dopamine and epinephrine significantly suppressed SENA to 38 +/- 9 and 15 +/- 6% of baseline, respectively. Low dose dopamine decreased arterial pressure and SENA. This suppression in SENA was attenuated but still observed after baroreceptor deafferentation. Dobutamine reduced SBV, but had no effect on SENA. These results suggest that dopamine and epinephrine primarily decrease SBV by venoconstriction in the splanchnic region, however, these effects are greatly modified by basal sympathetic discharge and changes in SENA and vascular tone.


Regional venous outflow, blood volume, and sympathetic nerve activity during hypercapnia and hypoxic hypercapnia. We examined the changes in systemic blood volume and regional venous outflow from the splanchnic, coronary, and other remaining vascular beds in response to acute hypercapnia or hypoxic hypercapnia in dogs, using cardiopulmonary bypass and a reservoir. Hypercapnia (PCO2 = 105 mmHg) (1 mmHg = 133 Pa) and hypoxic hypercapnia (PO2 = 23 mmHg, PCO2 = 99 mmHg) caused marked decreases in systemic blood volume of 14 +/- 3 and 16 +/- 3 mL/kg in spleen-intact dogs, and 3 +/- 2 and 10 +/- 2 mL/kg in splenectomized dogs, respectively. Splanchnic venous outflow increased by 12% at 3.5 min hypercapnia, whereas it decreased by 60% at 3.5 min hypoxic hypercapnia. Coronary venous outflow increased by 85 and 400% at 3.5 min hypercapnia and hypoxic hypercapnia, respectively. Sympathetic efferent nerve activity revealed a significant augmentation during hypoxic hypercapnia and a relatively smaller increase (30% of the response to hypoxic hypercapnia) during hypercapnia. Carotid and aortic chemoreceptor and baroreceptor denervation attenuated significantly the response of systemic blood volume to hypercapnia and hypoxic hypercapnia. The regional venous outflow responses to hypercapnia were not altered after chemodenervation, but those to hypoxic hypercapnia were significantly attenuated after chemodenervation. These results suggest that acute hypercapnia and hypoxic hypercapnia caused a marked decrease in vascular capacitance owing primarily to an increase in sympathetic efferent nerve activity via chemoreceptor stimulation. They also indicate that blood flow to the splanchnic vascular bed during hypercapnia increased (even though the cardiac output was constant), whereas it increased to the extrasplanchnic and coronary vascular beds during hypoxic hypercapnia.


Diabetic type of cardiomyopathy in food-restricted rats. We have demonstrated that food restriction that is associated with weight loss can produce a type of cardiac dysfunction similar to that produced by diabetes. As in diabetic atria, the food-restricted atria had a 2-fold increase in contraction force, rate of force development, and rate of force decline compared with controls. Both food-restricted and diabetic atria could tolerate anoxia better than controls. The contractile function of the whole perfused heart from the food-restricted rat was reduced, as in the case of the diabetic heart. As the left ventricular volume was increased, the left ventricular developed pressure and the rate of rise and fall in pressure were significantly reduced in both food-restricted and diabetic hearts, compared with those of age- and weight-matched controls. The positive inotropic responses of atria and whole perfused heart to increasing concentrations of extracellular calcium were similarly altered in food-restricted and diabetic hearts. The possible molecular mechanisms of these findings and some of the differences observed between food-restricted and diabetic hearts are discussed.


The influence of calcium on ANF release in the isolated rat atrium. We developed an in vitro model of the isolated, perfused rat atrium with which to examine the mechanisms linking muscular stretch to atrial natriuretic factor (ANF) secretion. It was shown that an increase in atrial pressure causing distension of the atria is associated with a rise in ANF secretion correlating with the degree of pressure load. Pressure-induced ANF secretion is enhanced by the calcium blocker nifedipine or omission of calcium from the perfusion buffer. The changes in atrial volume in response to a given pressure load are also more pronounced in the absence of calcium or following the addition of the calcium blocker. These data suggest that in nonbeating atria, stretch-induced ANF secretion does not rely on calcium influx.


Evidence for an effector role of endothelin in closure of the ductus arteriosus at birth. The ductus arteriosus is a special muscular shunt that in the fetus allows blood to bypass the unexpanded lungs. It closes rapidly after birth and this event is initiated by the physiologic rise in blood oxygen tension. Endothelin-1 has been proposed by us as a local mediator for oxygen after demonstrating that it is formed within the ductus and is a potent ductus constrictor. To confirm this possibility, we have now measured the release of endothelin-1 from the isolated ductus of near-term fetal lambs at different oxygen concentrations of the medium. In addition, using the same preparation, we have examined the effect on contractile tone of compounds interfering with the synthesis (phosphoramidon, 50 microM) and action (BQ123, 1 microM) of endothelin-1. We report that release of endothelin-1 from the ductus tends to increase with the oxygen concentration up to a value mimicking the neonatal condition. Phosphoramidon and, to a greater degree, BQ123 inhibit the contraction of the vessel to oxygen. These results implicate endothelin-1 as the effector agent for oxygen in the ductus and, by extension, assign to this peptide a critical role in the closure of the vessel at birth.


Extracellular ATP stimulates elastase secretion from human neutrophils and increases lung resistance and secretion from normal rat airways after intratracheal instillation. The effect of ATP on intracellular Ca2+ levels and elastase secretion in isolated normal human peripheral blood neutrophils was investigated as was its in vivo effect on lung resistance and mucous secretion. ATP (10(-5) M) increased [Ca2+]i from 61 +/- 3 to 165 +/- 15 nM in nonactivated neutrophils; elastase secretion was increased by 40% from nonactivated neutrophils but was unaffected in fMLP (10(-5) M) activated cells. Instillation of ATP (10(-5) and 10(-3) M) into the airways of brown Norway rats increased both lung resistance and secretion. These findings suggest that aerosolization of ATP into the cystic fibrosis-affected bronchial tree might be hazardous in terms of enhancement of parenchymal damage, which would result from neutrophil elastase release, and in terms of impaired respiratory lung function.


Inhibition of chick embryo hepatic uroporphyrinogen decarboxylase by components of xenobiotic-treated chick embryo hepatocytes in culture. II. A variety of xenobiotics, viz., 3,3',4,4'-tetrachlorobiphenyl (TCBP), sodium phenobarbital (PB), 3,5-diethoxycarbonyl-2, 4,6-trimethylpyridine (OX-DDC), and nifedipine, cause a decrease in uroporphyrinogen decarboxylase (UROG-D) activity, accompanied by uroporphyrin accumulation, in chick embryo hepatocytes in culture. In this study the activity of 17-day-old chick embryo hepatic UROG-D was determined by measuring the conversion of pentacarboxylporphyrinogen I to coproporphyrinogen I, and it was shown that a UROG-D inhibitor, previously reported to accumulate in TCBP-treated and PB-treated chick embryo hepatocytes in culture, also accumulates in OX-DDC-treated and nifedipine-treated chick embryo hepatocytes in culture. It was concluded that the accumulation of a UROG-D inhibitor provides an explanation for the UROG-D inhibition observed in this culture system with xenobiotics that cause uroporphyrin accumulation. Studies of the UROG-D inhibitory fraction isolated from the 10,000 x g, 40,000 x g, and 100,000 x g supernatant fractions of cultured chick embryo hepatocyte homogenate led to the conclusion that the UROG-D inhibitor is derived from a soluble component of the homogenate.


M2 muscarinic ([3H]N-methyl scopolamine) binding in micropunches of rat ventricular myocardium: characterization and modification by progesterone. A new technique is outlined for the characterization and quantification of M2 muscarinic binding sites (receptors) in micropunches (1 mm diam.), cut from slices (350 microns), of fresh cardiac tissue using the hydrophilic antagonist [3H]N-methyl scopolamine. The use of this water-soluble ligand allows us to label, and quantify, M2 receptors on the cell surface of intact cells contained within the micropunch. We believe that cardiac micropunches offer a simple but powerful approach to the investigation of membrane receptor regulation in tissue that largely retains the in vivo cytoarchitecture. Specific binding is reversible, stereospecific, saturable, of high affinity, and has the drug specificity typical of an M2 muscarinic receptor. In rat left ventricle, Bmax was 151.2 +/- 10.3 fmol/mg protein while KD was 1.0 +/- 0.1 nM. Nonspecific binding of the ligand was very low, varying from 2.8% (at 0.27 nM) to 7.7% (at 3.58 nM). This micropunch assay was used to determine that progesterone can compete with the muscarinic ligand for the M2 receptor in vitro (IC50 = 50 x 10(-6) M). The steroids estradiol and testosterone, as well as ouabain, were without effect. Progesterone inhibited [3H]N-methyl scopolamine binding competitively (KD reduced from 1.9 to 4.3 nM) without affecting the rate of association of the ligand. However, progesterone induced a rapid dissociation of the ligand from its receptor. We conclude that the micropunch assay described here is suitable for the continued study of sex hormone effects on cardiac function.


Impact of increased infarct transmurality on remodeling and function during healing after anterior myocardial infarction in the dog. To determine the impact of greater infarct transmurality on changes in left ventricular remodeling and function after acute anterior myocardial infarction, serial topographic and functional parameters (two-dimensional echocardiograms) and hemodynamics over 6 weeks, and postmortem topography (planimetry) at 6 weeks, were measured in chronically instrumented dogs randomized to standard coronary artery ligation (group 1) or a modified lower ligation plus collateral obliteration to decrease collateral inflow and increase transmurality (group 2). At 6 weeks, postmortem scar size and collagen were similar in the two groups, but group 2 had greater transmurality associated with more necrosis relative to area at risk, Q waves, infarct expansion, thinning, regional bulging, and cavity dilatation. Over the 6 weeks, group 2 showed more early expansion, late thinning and regional bulging in the short axis, larger diastolic and systolic volumes, and more apical aneurysmal bulging in the long-axis, reflecting more topographic deterioration. More important, group 2 showed greater regional and global left ventricular dysfunction over 6 weeks, lower ejection fraction at 2 days with further decrease over 6 weeks, and more left ventricular thrombus, ventricular arrhythmias, and deaths. In addition, transmurality correlated with the severity of remodeling and dysfunction. The findings indicate that transmurality is a major determinant of remodeling and left ventricular dysfunction during healing after anterior infarction.


85Sr uptake by the chick embryonic heart: effect of high doses of isoproterenol. The aim of the present study was to establish whether intraamnial administration of toxic doses of isoproterenol to chick embryos increases cardiac accumulation of strontium, the homologue element of calcium. It has been shown that the ability of embryonic tissues (blood, heart, and liver) to accumulate 85Sr decreases significantly during ontogeny. Administration of isoproterenol to chick embryos did not elevate the concentration of 85Sr in the heart. It seems, therefore, that isoproterenol-induced developmental changes in the chick embryonic myocardium are not necessarily due to intracellular calcium (as measured by 85Sr) overload.


Modulatory effect of steroid hormones on GnRH-induced LH secretion by cultured rat pituitary cells. The purpose of the present experiments was to examine the short- and long-term effects of estradiol-17 beta (E2), progesterone (P), and 5 alpha-dihydrotestosterone (DHT), alone and in combination, on the gonadotrophin-releasing hormone (GnRH)-induced luteinizing hormone (LH) secretion, using an ovariectomized rat pituitary cells culture model. After 72 h in steroid-free medium, pituitary cells were further cultured for 24 h in medium with or without E2 (1 nM), P (100 nM), or DHT (10 nM). Cultures were then incubated for 5 h in the absence or presence of 1 nM GnRH with or without steroids. LH was measured in the medium and cell extract by radioimmunoassay. The results show that the steroid hormones exert opposite effects on the release of LH induced by GnRH, which seems to be dependent upon the length of time the pituitary cells have been exposed to the steroids. In fact, short-term (5 h) action of E2 resulted in a partial inhibition (64% of control) of LH release in response to GnRH, while long-term (24 h) exposure enhanced (158%) GnRH-induced LH release. Similar results were obtained with DHT, although the magnitude of the effect was lower than with E2. Conversely, P caused an acute stimulatory action (118%) on the LH released in response to GnRH and a slightly inhibitory effect (90%) after chronic treatment. GnRH-stimulated LH biosynthesis was also influenced by steroid treatment. Significant increases in total (cells plus medium) LH were observed in pituitary cells treated with E2 or DHT.(ABSTRACT TRUNCATED AT 250 WORDS)


Intrafibre distribution of succinate dehydrogenase in cat tibialis anterior motor units. Using isolated ventral root filament stimulation and glycogen depletion techniques, 14 motor units from the cat tibialis anterior were studied. Based on their mechanical properties, the units were classified as either slow-fatigue resistant, fast-fatigue resistant, fast-fatigue intermediate, or fast-fatigable. Quantitative histochemical and computer assisted image analysis techniques were used to determine the activity of succinate dehydrogenase in a population of fibres in each unit. In addition, the intrafibre distribution of succinate dehydrogenase activity was measured in those same fibres by calculating the enzymatic activity of circumferential layers every 0.5 microns starting from the fibre edge to its centre. It was established that enzymatic activity and radial distance were linearly related in the fibres. A range in succinate dehydrogenase activity (mean coefficient of variation, 29%) was observed among the fibres of a unit. In contrast, the intrafibre distribution of that activity was rather consistent (mean variation, 4%) across the fibres of a unit. Further, the intrafibre distribution was similar among the fibres of units classified as the same type. However, the intrafibre distribution was disparate among the different unit types. These data suggest that the intrafibre distribution of mitochondrial enzymes may contribute to the mechanical properties of a motor unit. In this regard, a hypothesis is proposed that describes how the absolute activity of a mitochondrial enzyme, and the intrafibre distribution of that activity, may interactively contribute to the fatigue resistance of a unit.


Reversibility of renal tubular dysfunction in streptozotocin-induced diabetes in the rat. Enzymuria and specific proteinuria were examined over a period of 19 days in 4 groups of 5 rats: a control group, a nondiabetic polyuric group, a group of streptozotocin-induced diabetic rats treated with insulin as of the 10th day after the injection of the drug, and a similar group of untreated diabetic rats. Increased urinary excretion of beta-N-acetyl-D-glucosaminidase, lactate dehydrogenase, and alanine aminopeptidase was observed shortly after the induction of diabetes. It was partly or totally reversible following insulin treatment. Nondiabetic polyuria had a slight effect on the excretion of alanine aminopeptidase only. The urinary excretion of beta 2-microglobulin also rapidly increased after the onset of diabetes to a level approximately 50 times the control values. This effect was largely reversible with insulin treatment and was absent in the nondiabetic polyuric group. A small but significant 3-fold increase in albumin excretion was also noted but was not affected by insulin treatment. We conclude that streptozotocin-induced diabetes causes an early tubular dysfunction that is unrelated to polyuria and is reversible upon insulin treatment. This tubular dysfunction is best revealed by the urinary excretion of the low molecular weight protein beta 2-microglobulin. Our results suggest that it would be of interest to further examine the usefulness of sensitive markers of tubular dysfunction, especially low molecular weight proteinuria, in the detection of early stages of diabetic nephropathy.