Incorporation and metabolic conversion of saturated and unsaturated fatty acids in SK-Hep1 human hepatoma cells in culture. We report here a study of the incorporation and metabolism of various long chain fatty acids in SK-Hep-1 cultured hepatoma cells. Medium supplementation with radiolabelled palmitic, stearic, linoleic, alpha-linolenic and eicosa-8,11,14-trienoic acids (1 microM, 24 H) resulted in an active uptake of each of these precursors by the cultures. Subsequent analysis of the cellular lipids indicated that they exhibit almost all the enzymic activities of polyunsaturated fatty acid metabolism that are characteristic of normal hepatic cells. With respect to the desaturation capacities of this cell line, although alpha-linolenic acid reacted more extensively than did linoleic acid and the conversion of 8,11,14-eicosatrienoic acid by the delta 5 specific enzyme was more avid than had been previously seen in normal rat or human liver: the saturated fatty acids constituted relatively poor substrates, being preferentially chain-elongated rather than (mono) desaturated at the delta 9 position. Analysis of the fatty acid profiles of total cellular lipids and of various lipid subclasses, however, revealed a relative paucity of essential fatty acids when compared with the abundance of endogenous monoenoic acids (particularly oleic). Of the total cellular fatty acids, 58% were present in the form of phospholipids; with 33% of the remaining 42% (i.e., the neutral lipids) being associated with triacylglycerol fraction. Within the total lipids, phosphatidyl-choline and phosphatidyl-ethanolamine were the major sites for the incorporation of all metabolic products derived from the incubated radiolabelled 16- and 18-carbon fatty acid precursors, whereas the phosphatidyl-inositol fraction was the predominant recipient of nascent arachidonic acid when the eicosatrienoate was the substrate. The express purpose of this investigation was to characterize the biochemical routes involved in the anabolism of various essential fatty acids in the human hepatocyte, through the use of cultured human hepatoma cells as an experimental model system. In view of the similarities between certain aspects of the polyunsaturated fatty acid metabolism of these cells and the corresponding properties of other mammalian hepatic or liver-derived tissues, the data presented here would thus constitute a significant beginning alone those lines. Moreover, considering the extreme difficulty in obtaining for such investigation relevant tissue samples from normal human sources, we regard these results- and the availability for use of this particular human hepatoma cell line-as important new developments in the effort to characterize a useful experimental model both for gaining immediate information and for designing future experiments.


Phosphoinositide kinases in rat heart sarcolemma: biochemical properties and regulation by calcium. Phosphatidylinositol (PtdIns) kinase and phosphatidylinositol 4-phosphate (PtdIns4P) kinase have been studied in a purified sarcolemmal fraction isolated from rat heart. Both enzymes were Mg(2+)-dependent and their activities were maximal at 2.5 mM Mg2+ and pH 7.5. Kinetic analysis of endogenous substrate phosphorylation by ATP showed that the apparent Km and Vmax values for PtdIns kinase were 292 +/- 17 microM and 1390 +/- 80 pmol.mg-1.min-1, respectively, while the apparent Km and Vmax values for PtdIns4P kinase were 398 +/- 25 microM and 382 +/- 24 pmol.mg-1.min-1. Under normal conditions, the activity of PtdIns4P kinase was lower than that of PtdIns kinase; however, the former activity increased several fold in the presence of PtdIns4P as an exogenous substrate. The enzymatic synthesis of intramembranal PtdIns4P and phosphatidylinositol 4,5-bisphosphate (PtdIns (4,5)P2) was maximally enhanced by 0.1% Triton X-100 and inhibited by micromolar concentrations of Ca2+. Inhibition of PtdIns and PtdIns4P kinase showed IC50 values for Ca2+ of 20 and 6 microM, respectively, and was independent of either Ca(2+)-induced activation of phospholipase C and polyphosphoinositide monophosphoesterases or low ATP concentrations. The results indicate that purified rat heart sarcolemmal membranes contain a very active phosphoinositide phosphorylation system which is regulated by micromolar levels of Ca2+. The Ca2+ effect may contribute to the feedback inhibition of the receptor-activated formation of inositol 1,4,5-trisphosphate.


The in vivo inhibition of transport enzyme activities by chloroquine in different organs of rat is reversible. The antimalarial drug chloroquine is found to inhibit Na+, K(+)-ATPase, Ca2+, Mg(2+)-ATPase, Ca(2+)-ATPase, pNPPase and acetylcholinesterase activities in different organs of rat in vivo when injected for a certain periods of time. The inhibition seems to be due to the changes in the level of phospholipid, cholesterol and the fatty acid of the lipid and the alteration of the fluidity of the microsomal membranes. However, the enzyme activities return to the normal level in about 2-3 weeks after the discontinuation of the drug suggesting that the drug effect is reversible.


2,5-Hexanedione-induced intermediate filament aggregates contain ubiquitin-protein conjugate immunoreactivity and resemble Rosenthal fibres. A number of chronic degenerative disorders including cerebellar astrocytomas and Parkinson's disease are characterized by the presence of cytosolic inclusions which contain intermediate filament (IF) aggregates and ubiquitin-protein conjugate immunoreactivity. In cerebellar astrocytomas these inclusions are known as Rosenthal fibres. 2,5-hexanedione (HD) treatment is known to induce IF aggregates in cells in culture. HD-induced aggregates have therefore been studied as a potential model for the clinical inclusions. Exposure of astrocyte cultures to 2 mM HD for 2 or 4 weeks led to the formation of aggregates of the IFs (glial fibrillary acidic protein and vimentin). The aggregates contained ubiquitin-protein conjugates, which, on electron microscopy appeared to be localized in a peripheral shell. In addition, ubiquitin mRNA levels were found to be elevated approximately threefold by HD treatment. HD-induced inclusions and Rosenthal fibres were found to share a number of features. HD administration, therefore, appears to be a suitable model for the production of pathological inclusions.


Effect of Cu(2+)-ascorbic acid on lipid peroxidation, Mg(2+)-ATPase activity and spectrin of RBC membrane and reversal by erythropoietin. The effect of erythropoietin (Ep), a glycoprotein hormone, has been studied on lipid peroxidation induced by Cu2+ and ascorbate in vitro, Mg2+ ATPase activity and spectrin of RBC membrane. Our present investigation reveals that Cu2+ and ascorbic acid increases lipid peroxidation of RBC membrane significantly. It has further been observed that under the same experimental condition spectrin, a major cytoskeleton membrane protein, and Mg(2+)-ATPase activity of RBC membrane decrease significantly. However, exogenous administration of Ep completely restores lipid peroxidation and Mg(2+)-ATPase activity and partially recovers spectrin of RBC membrane.


Desensitization of the hypothalamic-pituitary-adrenal axis following prolonged administration of corticotropin-releasing hormone or vasopressin. The responses of the hypothalamic-pituitary-adrenal axis during chronic stress are characterized by normal or slightly elevated plasma ACTH, increased hypothalamic corticotropin-releasing hormone (CRH) and vasopressin secretion, decreased pituitary CRH receptors and hypersensitivity of the ACTH and glucocorticoid responses to a novel stress. To determine the role of CRH and vasopressin in the pituitary hyperresponsiveness to a superimposed stress, pituitary CRH receptors and plasma ACTH responses were measured in rats receiving minipump infusions of CRH or a combination of CRH and vasopressin (VP), 50 ng/min of each for 50 h. Rats were killed by decapitation with or without exposure to ether vapor for 5 min or immobilization for 15 or 30 min, and blood was collected for ACTH and corticosterone determinations. The pituitary CRH receptor concentration measured by binding 125I-Tyr-oCRH, was reduced by 45 and 80% in CRH- and CRH-plus-VP-infused rats, respectively, with no changes in receptor affinity. Acute stress by ether exposure or immobilization had no effect on pituitary CRH receptors. Adrenal weight was significantly increased, and thymus weight decreased in CRH-infused animals, indicating activation of the pituitary adrenal axis. However, in contrast to the responses following chronic stress, the increases in plasma ACTH in response to an injection of 10 micrograms/kg CRH or acute stress were significantly lower in CRH- and CRH-plus-VP-infused rats. Furthermore the content and release of ACTH from quartered pituitaries were also decreased in chronically treated rats.(ABSTRACT TRUNCATED AT 250 WORDS)


Activation of GABA B receptors in the anterior pituitary inhibits prolactin and luteinizing hormone secretion. Previous work from our laboratory showed that baclofen could lower serum prolactin (PRL) levels acting at the central nervous system. The present experiments were designed to evaluate whether the gamma-aminobutyric acid B agonist was also effective in inhibiting hormone release at the pituitary level. In monolayer cultures of adenohypophyseal dispersed cells, baclofen inhibited basal PRL secretion after 1 or 2 h of incubation. This inhibition was significantly abolished by three antagonists: phaclofen, 3-aminopropyl-phosphonic acid and 4-aminobutylphosphonic acid. Furthermore, baclofen inhibited the thyrotropin-releasing hormone-induced PRL release in a concentration-dependent manner. With regard to gonadotropin secretion, baclofen was unable to modify basal luteinizing hormone (LH) secretion, but significantly inhibited the LH-releasing hormone-induced LH release. These results show that baclofen, in addition to its central neuroendocrine effects, inhibits pituitary hormone secretion, under basal and/or stimulated conditions, by direct action at the pituitary level.


Placental corticotropin-releasing hormone and pituitary-adrenal function during pregnancy. The placenta secretes large amounts of the hypothalamic releasing hormone, corticotropin-releasing hormone (CRH), into both the maternal and fetal circulation during pregnancy. We characterized the relationship between maternal plasma CRH and products of the pituitary and adrenal in order to investigate the physiologic role of placental CRH in modulating maternal pituitary-adrenal function. Plasma was obtained from 8 women at biweekly intervals between 21 and 40 weeks of full-term pregnancy for CRH, adrenocorticotropin (ACTH), alpha-melanocyte-stimulating hormone (alpha MSH), cortisol, and dehydroepiandrosterone sulfate (DHEAS) measurements by radioimmunoassay. Eighteen women were also studied once at 22-34 weeks of pregnancy with plasma CRH and 24-hour urinary free cortisol measurement. Eight nonpregnant women served as control subjects. Plasma CRH was undetectable in the nonpregnant subjects and rose over the time period studied in the pregnant women. Concentrations of afternoon ACTH and cortisol also rose during pregnancy while DHEAS levels declined in the pregnant women. The alpha-MSH levels were beneath the level of detection (< 20 pg/ml) in both the pregnant and nonpregnant subjects. The overall mean afternoon ACTH concentration was higher in the pregnant than in the nonpregnant women (11.4 +/- 1.8 vs. 5.9 +/- 1.8 pg/ml; p < 0.05), although the ACTH levels in both groups remained within the normal range. The mean plasma cortisol concentrations were higher in the pregnant women, while the mean DHEAS levels were lower in the pregnant women when compared to the nonpregnant subjects.(ABSTRACT TRUNCATED AT 250 WORDS)


Bladder distention activates noradrenergic locus coeruleus neurons by an excitatory amino acid mechanism. The present study was designed to determine the neurotransmitter(s) involved in activation of noradrenergic locus coeruleus neurons by urinary bladder distention. The spontaneous discharge rate of single locus coeruleus neurons was recorded from halothane-anesthetized rats during the physiological challenge of bladder distention. Intrabladder saline infusion (0.5 ml) increased bladder pressure by 77 +/- 9.7 mmHg (n = 19) and this was associated with an increase in locus coeruleus discharge rate of 53 +/- 4.8% (n = 29). Simultaneous recordings of cortical electroencephalographic activity demonstrated that electroencephalographic activation, characterized by a decreased amplitude and tendency to shift from low frequency activity to higher frequency activity, was also associated with bladder distention. The role of corticotropin-releasing factor and excitatory amino acid inputs to the locus coeruleus in activation by bladder distention was tested in rats pretreated with a corticotropin-releasing factor antagonist, or excitatory amino acid antagonists. Intracerebroventricular administration of the corticotropin-releasing factor antagonist did not alter locus coeruleus activation by bladder distention. In contrast, both locus coeruleus activation and electroencephalographic activation associated with bladder distention were prevented by intracerebroventricular administration of kynurenic acid. The same dose of kynurenic acid also prevented locus coeruleus activation by repeated sciatic nerve stimulation, as previously reported. Local administration of kynurenic acid into the locus coeruleus greatly attenuated, but did not completely prevent the increase in locus coeruleus discharge elicited by bladder distention.(ABSTRACT TRUNCATED AT 250 WORDS)


Redistribution of secretory granule components precedes that of synaptic vesicle proteins during differentiation of a neuronal cell line in serum-free medium. Incubation of the rat sensory neuron-derived cell line ND7 in serum-free medium results in the arrest of mitosis and the appearance of numerous neuronal processes. During this differentiation event, secretory granule components such as chromogranins, neuropeptide Y and the C-flanking peptide of pro-neuropeptide Y move to the tips of the majority of the neuronal processes regardless of process length. In contrast, the synaptic vesicle component, synaptophysin, is found only at the tips of the very long processes which appear following prolonged periods of culture in serum-free medium. A similar restriction of synaptophysin to long processes is also observed following differentiation and process formation induced by other treatments such as incubation in reduced serum or treatment with cyclic AMP or phorbol myristate acetate. Hence the regulated secretory pathway associated with the chromogranins and neuropeptides appears to be segregated into the processes at an earlier stage of ND7 differentiation than the synaptophysin-associated synaptic vesicle pathway. ND7 cells therefore provide a model system for studying the processes regulating these pathways and the redistribution of their components during neuronal differentiation.


GABAA receptor subunit messenger RNAs show differential expression during cortical development in the rat brain. Developmental changes of the expression of various GABAA receptor subunits (alpha 1, alpha 3, alpha 4, beta 1-3, and gamma 2) were examined in the fetal rat cerebral cortex using in situ hybridization histochemistry. The subunits showed three main patterns of development. The alpha 1 subunit showed the first pattern, in which no expression was observed during embryonic development. The alpha 4 and beta 1 subunits showed the second pattern, in which expression was observed in both the undifferentiated neuroepithelium and the developing cortical layers. The alpha 3, beta 2, beta 3, and gamma 2 subunits showed the third pattern, in which expression was only seen in the developing cortical layers. These findings strongly suggest the following: (i) the alpha 1 subunit is involved in GABAergic transmission in the mature cerebral cortex; (ii) the alpha 4 and beta 1 subunits are involved in both the differentiation of the neuroepithelium and the development of the cortical plate, and (iii) the alpha 3, beta 2, beta 3, and gamma 2 subunits are involved in the development of the cortical plate. Subunits already expressed on embryonic day 13 (beta 1, beta 3, and gamma 2) appear especially likely to have a special role in neuronal development.


Redistribution of B-50/growth-associated protein 43 during differentiation and maturation of rat hippocampal neurons in vitro. Morphologically polarized hippocampal neurons, grown in culture for two days, contain immunoreactivity of the growth-associated protein B-50 along the plasma membrane of both dendrites and axons. In mature hippocampal neurons, both in vitro and in vivo, B-50 is located in the axon. In order to assess at which stage during neuronal differentiation B-50 is selectively located in the axon, an immuno-light and electron-microscopic study was performed on rat hippocampal neurons developing in vitro. B-50 immunofluorescence was detected in the axon, dendrites and soma of two-day-old polarized neurons. Simultaneously, microtubule-associated protein 2, a marker specific to dendritic microtubules, was predominantly found in the soma, the short dendritic processes and at the base of axonal growth cones. In hippocampal neurons cultured beyond seven days in vitro, microtubule-associated protein 2 immunofluorescence is restricted to the cell soma and dendrites. The spatial distribution of B-50, however, varies. In solitary neurons maturing without interneuronal contacts, B-50 immunofluorescence is observed in axons and in the dendrosomatic domain characterized by the presence of microtubule-associated protein 2. In contrast, in high-density cell cultures B-50 immunofluorescence is absent in the cell body and dendrites, but punctate in axons running along the dendrites. Electron microscopy was carried out on hippocampal neurons of eight to 21 days in vitro to study the process of redistribution of B-50 at the subcellular level. In neurons of eight days in vitro with prominent synapses, B-50 immunoreactivity is significantly elevated at the axonal plasma membrane compared to the plasma membrane of the dendrites and the soma. In neurons from the same culture without synapses, B-50 immunoreactivity is distributed rather densely along the plasma membrane of the soma, dendrites, and on the axonal plasma membrane. A similar B-50 distribution is observed in mature neurons cultured at low cell density without interneuronal cell contacts, for 15 days in vitro. In high-density cell cultures of 21 days in vitro, B-50 is virtually absent at the plasma membrane of the soma and dendrites, and heterogenously distributed along the plasma membrane of axon and axonal varicosities. Our results indicate that selective sorting of B-50 into axons occurs after initial morphological polarization of hippocampal neurons and is correlated with the formation of synapses and with the cessation of dendritic outgrowth.


Development of Na(+)- and K(+)-currents in the cochlear ganglion of the chick embryo. The development of Na(+)- and K(+)-currents in the primary afferent neurons of the cochlear ganglion was studied using the patch-clamp technique. Cells were dissociated between days 6 and 17 of development and membrane currents recorded within the following 24 h. Outward currents were the first to appear between days 6 and 7 of embryonic development and their magnitude increased throughout development from 200 pA on day 7 to 900 pA on days 14-16. Threshold for activation decreased by 20 mV between days 8 and 14. Outward currents were absent when Cs+ replaced K+ in the pipette and were partially blocked by external tetraethylammonium. Outward currents contained at least three components: (i) a non-inactivating outward current, similar to the delayed-rectifier, predominating in mature neurons; (ii) a slowly inactivating current (tau about 200 ms), most evident in early and intermediate stages (days 7-10); and (iii) a rapidly inactivating outward current (tau about 20 ms) similar to the A-current (IA) described in other neurons, which was distinctly expressed in mature neurons. Sodium currents were identified as fast transient inward currents, sensitive to tetrodotoxin and extracellular Na(+)-removal. They appeared later than K(+)-currents and increased in size from about 100 pA between days 9-11 to 600 pA by days 13-16. The development of membrane currents in cochlear ganglion neurons corresponded to defined stages of the innervation pattern of the chick cochlea [Whitehead and Morest (1985) Neuroscience 14, 255-276]. These currents could be functionally related to the establishment of synaptic connections between transducing cells and primary afferent neurons.


Effects of stress on opioid receptor binding in the rat central nervous system. The endogenous opioid peptides are known to play a significant role in the modulation and/or mediation of numerous environmental or experimental stressors. However, the specific opioid peptide(s) and receptor type(s) involved, under what physiologic conditions they are engaged and within which regions of the CNS is not well understood. We therefore examined the effects of both a chronic and an acute stressor-90-h water deprivation and a single 20-min foot shock on opioid receptor binding in 17 specific rat brain nuclei. [3H]DSTLE (Tyr-D-Ser-Gly-Phe-Leu-Thr) and [3H]DAGO(Tyr-D-Gly-Phe-NMe-Phe-Gly-ol) were used to label delta and mu receptors, respectively. Foot shock induced profound antinociception as measured by tail-flick latency which outlasted the stressor by several minutes. However, only the septum responded with a decrease in [3H]DAGO binding to this type of stress-induced analgesia. No other alterations in either [3H]DAGO or [3H]DSTLE binding were seen in response to foot shock. In contrast, water deprivation induced increases in [3H-DAGO] binding in the septum as well as increases in [3H]DSTLE binding in the caudate and accumbens nuclei. Moreover, the presumptive mild stress of handling in the foot shock control group was sufficient to decrease mu or delta receptor binding in seven out of 17 brain regions investigated (including the frontal cortex and olfactory tubercle where both mu and delta binding were increased) when compared to unhandled deprivation control animals. These changes in opioid receptor binding may have been the result of alterations in treatment-induced peptide release, receptor regulation, or interactions with other released neurotransmitter ligand/receptor complexes.(ABSTRACT TRUNCATED AT 250 WORDS)


Differential subcellular distribution of the alpha 6 subunit versus the alpha 1 and beta 2/3 subunits of the GABAA/benzodiazepine receptor complex in granule cells of the cerebellar cortex. The distribution of the alpha 6 subunit of the GABAA receptor has been established in rat cerebellum and compared to the distribution of the alpha 1 (cat) and the beta 2/3 (rat, cat) subunits, using immunocytochemistry. The synapses established by Golgi cell terminals on the dendrites of granule cells were immunoreactive for the alpha 6, alpha 1 and beta 2/3 subunits in virtually all glomeruli, indicating that two variants (alpha 1 and alpha 6) of the same subunit are co-localized at the same synapses. The somatic membranes of the granule cells, which receive no synapses, were immunopositive for the alpha 1 and beta 2/3 subunits, but not for the alpha 6 subunit. Thus, the alpha 1 and the beta 2/3 subunits are located at both synaptic and extrasynaptic sites, but the alpha 6 subunit is detectable only at synaptic sites.


Different action of ethosuximide on low- and high-threshold calcium currents in rat sensory neurons. The effects of ethosuximide on calcium channels were studied on dorsal root ganglion neurons from one-day-old rats using the patch-clamp technique. Bath application of ethosuximide induced dose-dependent and reversible suppression of calcium currents without affecting their time-course. Substantial differences between the effects of ethosuximide on the low-threshold and high-threshold (T- and L-) currents were observed. Ethosuximide reduced the T-current with greater potency than the L-current (Kd for T-current is 7 microM vs 15 microM for L-current). This relative specificity of its action still remained if applied at concentrations up to 1 mM. These data support the hypothesis according to which the anti-epileptic action of ethosuximide is related to reduction of the low-threshold calcium currents in sensory neurons.


Glutathione: new candidate neuropeptide in the central nervous system. The physiological significance of glutathione in the mammalian central nervous system is still uncertain, although some evidence indicates that it may be an important regulatory peptide. In the present study, the distribution and characteristics of glutathione binding sites in the brain have been studied. Biotinyl-glutathione was synthesized as a probe to detect glutathione binding sites in the CNS. Specific glutathione binding sites in the brain were largely localized to the white matter, suggesting the presence of glutathione receptors on neuroglial cells. The colloidal gold technique and immunofluorescence double staining allowed the visualization of the receptor at the cellular level and thus demonstrated that there are glutathione receptors on cultured astrocytes. Glutathione applied to cultured astrocytes elicited increased levels of intracellular inositol-1,4,5-trisphosphate, suggesting that glutathione receptors were coupled to phospholipase C. The localization of glutathione receptors on astrocytes and the activation of a second messenger system by glutathione suggest that glutathione may be a neuropeptide in the central nervous system.


In vitro responses of caudal hypothalamic neurons to hypoxia and hypercapnia. Results from previous studies have suggested that the hypothalamus modulates cardiorespiratory responses to hypoxia and/or hypercapnia. Many neurons in the caudal hypothalamus are stimulated by hypercapnia and hypoxia in vivo; however, it is not known if these responses are dependent upon input from other areas. Whole-cell patch and extracellular recordings from a brain slice preparation were used in the present study to determine the direct effects of hypoxia (5% CO2/95% N2 or 10% O2/5% CO2/85% N2) and hypercapnia (7% CO2/93% O2) on caudal hypothalamic neurons in vitro. Coronal sections (400-500 microns) were obtained from young Sprague-Dawley rats and placed in a recording chamber that was perfused with nutrient media equilibrated with 95% O2/5% CO2. Extracellular recordings demonstrated that hypoxia stimulated over 80% of the neurons tested; the magnitude of the response was dependent upon the degree of hypoxia. In addition, over 80% of cells that were excited by hypoxia retained this response during synaptic blockade. Hypercapnia increased the discharge frequency of 22% of the caudal hypothalamic neurons that were studied. A second set of caudal hypothalamic neurons were studied with whole-cell patch recordings; the mean resting membrane potential of these neurons was -51.8 +/- 1.0 mV with an average input resistance of 399 +/- 49 M omega. Hypoxia produced a depolarization in 76% of these neurons; a poststimulus hyperpolarization often occurred. A depolarization and/or increase in discharge rate during hypercapnia was observed in 35% of the neurons tested. Only 10% of all neurons studied were excited by both hypoxia and hypercapnia. These findings suggest that separate subpopulations of caudal hypothalamic neurons are sensitive to hypoxia and hypercapnia. Thus, this hypothalamic area may be a site of central hypoxic and hypercapnic chemoreception.


[Orthotopic liver transplantation and hepatocellular carcinoma]. Nineteen orthotopic liver transplantations (OLT) were performed in patients with hepatocellular carcinoma, between March 1988 and December 1990, in our Department. Thirteen patients (68.4%), 10 men and 3 women, mean age 48.2 +/- 2.8 years, were clear cut neoplastic disease, six patients (31.6%), 4 men and 2 women, mean age 48.6 +/- 4.2 years, were incidental tumors. Three years survival rate was 20% in clear cut neoplastic diseases (4 patients died for neoplastic recurrence) and 66% in incidental tumors. Our results demonstrate that liver transplantation for hepatobiliary malignancy is still justified, patient selection is important in predicting outcome.


Coevolution of cytokine receptor families in the immune and nervous systems. Close relationships between the nervous system and immune systems at molecular levels have now become evident. Receptors for CDF/LIF and CNTF, i.e., factors which play important roles in the nervous system, share a close structural similarity to those for IL-6, which is a molecule acting in the immune system. Receptors for these three factors belong to a subtype of cytokine receptor family (class IB cytokine receptor). We have constructed a higher subdomain structure of the receptor for CDF/LIF based on its known primary structures. The receptor contains immunoglobulin and fibronectin-like domains, in addition to common domains of the cytokine receptor, similar to those cell surface molecules of the neural immunoglobulin gene super family. These domains appear to have similar structures to the immunoglobulin. These lines of evidence suggest that the class IB cytokine receptor was formed as a result of those fusion of the genes for a more primitive cytokine receptor IA and for the neural immunoglobulin super gene family, and that, likewise, many molecules regulating neural development and those which act in the immune system have a common evolutionary origin.


Conduction velocity of low-threshold mechanoreceptive afferent fibers in the glabrous and hairy skin of human hands measured with microneurography and spike-triggered averaging. The axonal conduction velocity (CV) of afferent fibers innervating low-threshold mechanoreceptors in the skin of the human hand was measured utilizing a spike-triggered averaging technique. Two tungsten microelectrodes were inserted into the median, or the ulnar, the superficial branch of the radial nerve, at two different points in the distal forearm. Unitary spike potentials were picked up with the proximal electrode. Unit-type SA (I and II), and FA (I and II), was determined from receptive field properties and response patterns to mechanical stimuli. Using these potentials as a trigger, the records from the distal electrode were averaged to reveal corresponding unitary potentials embedded in the background noise activities. CVs were calculated by dividing the interelectrode distance by the conduction time measured from the two neurograms. 122 mechanoreceptive afferent fibers in the glabrous and the hairy skin were recorded. The CVs of all sampled units were 36-73 m/s and the mean (SD) was 58.7 (7.4) m/s. The CVs did not differ between units in the three nerves, nor between units from the glabrous and the hairy skin. The mean CV of the FAI group was slower than the mean CV of the SA group by 4-5 m/s, but the overlap of the distributions was large.


Mechanism of the reflex inhibition of micturition contractions of the urinary bladder elicited by acupuncture-like stimulation in anesthetized rats. The effects of acupuncture-like stimulation of various segmental areas on the rhythmic micturition contractions (RMCs) of the urinary bladder were examined in anesthetized rats. The urinary bladder was cannulated via the urethra and expanded by infusing saline until the urinary bladder produced micturition contractions rhythmically as a consequence of the rhythmic burst discharges of the vesical pelvic efferent nerves. An acupuncture needle, having a diameter of either 160 or 340 microns, was inserted to a depth of about 4-5 mm into the skin and underlying muscles at various segmental areas, rostrally from the face then caudally to the hindlimb. Once being inserted, the needle was twisted left and right with the fingers about once every second for 1 min. (1) Acupuncture-like stimulation applied to the perineal area inhibited both the RMCs and the rhythmic burst discharges of vesical pelvic efferent nerves without any significant changes in the hypogastric efferent nerve activity. By contrast, stimulation applied to the face, neck, forelimb, chest, abdomen, back, and hindlimb areas was ineffective. (2) After surgically separating the perineal skin from the underlying muscles with the main cutaneous nerve branches intact, stimulation of either the perineal skin or the perineal muscles inhibited the RMCs. Stimulation of the perineal muscles produced a stronger inhibition of the RMCs than that of the perineal skin. (3) Stimulation of the perineal area increased afferent nerve activity, either recorded from the pudendal nerve branches innervating the perineal skin or underlying muscles, or recorded from the pelvic nerve branches innervating the perineal muscles. (4) The stimulation-induced inhibition of the RMCs was abolished after surgically severing both pudendal and pelvic nerve branches that innervated the perineal skin and underlying muscles. (5) The present findings indicate that the inhibition of the RMCs following acupuncture-like stimulation of the perineal area is a reflex response characterized by segmental organization. The afferent arcs of the reflex are both pelvic and pudendal nerve branches innervating the perineal skin and underlying muscles, while the efferent arcs are pelvic nerve branches innervating the urinary bladder.


Delayed appearance of G-protein coupled signal transduction system in developing cerebellar Purkinje cell dendrites. To investigate the relation between the function of Ca(2+)-activated K+ channels and phosphoinositide turnover, we have examined the physiological and pharmacological characteristics of ionotropic and metabotropic quisqualate (QA) receptors in rat cerebellar Purkinje cells during development using the slice-patch method combined with Ca2+ imaging. The typical response to QA obtained from a rat on postnatal day (PND) 21 consisted of three components: (1) a fast inactivating inward current, (2) a slow inward current, and (3) a slow outward current. The slow inward current was abolished in Ca(2+)-free medium, while the fast inactivating inward current and the slow outward current remained unaffected. The slow outward current which appeared to be activated via a metabotropic receptor was not observed in the Purkinje cell of PND 7 rat, in which dendrites were poorly developed but its amplitude increased linearly with PND. QA caused significant increases in [Ca2+]i in the fully developed dendritic region of the Purkinje cells even in Ca(2+)-free medium, suggesting a dendritic localization of the metabotropic receptors.


Dissection of bradykinin-evoked responses by buffering intracellular Ca2+ in neuroblastoma x glioma hybrid NG108-15 cells. Signal transduction pathways from bradykinin (BK) receptors were investigated in NG108-15 neuroblastoma x glioma hybrid cells by buffering the intracellular calcium (Ca2+) with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA), a Ca2+ chelator. BK increased inositol-1,4,5-trisphosphate (Ins(1, 4,5)P3) formation at the same rate in the control and in BAPTA-acetoxy methyl ester (AM)-treated NG108-15 cells. However, a transient increase of intracellular Ca2+ concentrations in response to BK was significantly suppressed in Ca(2+)-buffered hybrid cells. Accordingly the BK-induced outward current was inhibited in BAPTA-AM-treated hybrid cells, while the subsequent inward current associated with a fall in membrane conductance was apparently increased. The initial phase of acetylcholine release from NG108-15 cells in response to BK was markedly inhibited in BAPTA-AM-treated coculture dishes when detected as miniature end-plate potentials of myotubes, though the late phase of acetylcholine secretion was observed. These results indicate that BK induces two distinct responses in NG108-15 cells: Ins(1,4,5)P3-dependent intracellular Ca2+ rise-sensitive and -insensitive components.


Gradient expression of neural cell adhesion molecule (NCAM) in the pontine migratory stream of fetal rats. Immunohistochemical localization of a neural cell adhesion molecule (NCAM) was examined in the subpial pontine migratory stream of the fetal rat with a monoclonal antibody specific for the rat NCAM, MAb-AF11. Although the pontine cell strand showed weaker expression of NCAM than the parenchymal areas of the brainstem, within the cell strand, NCAM-immunoreactivity was somewhat greater in the anterior part of the stream near the neurons' destination than the caudal part. The weak NCAM gradient in the pontine migratory stream may contribute to formation of the pontine cell strand and the basal pontine gray.


Burst discharges of fastigial neurons in macaque monkeys are driven by vision- and memory-guided saccades but not by spontaneous saccades. Discharges from 61 saccadic burst neurons in the fastigial oculomotor region were recorded for two trained macaque monkeys during vision-guided or memory-guided saccades or spontaneous saccades in the dark. Although these neurons exhibited vigorous, burst discharges during both vision-guided and memory-guided saccades, only weak bursts were observed during spontaneous saccades in the dark. Especially in 10 of the 61 neurons, saccadic burst discharge was almost completely absent during spontaneous saccades in the dark. These findings suggest that the cerebellum plays an important role in the control of vision-guided saccades as well as memory-guided saccades, but not of spontaneous saccades in the dark.


Ocular convergence-related neuronal responses in the lateral suprasylvian area of alert cats. Neuronal spike discharges were recorded from the lateral suprasylvian (LS) area while ocular convergence was elicited in five alert cats. Ocular convergence was elicited by presenting a visual target moving in depth. Cats were rewarded for convergence eye movement. In 9 out of 426 cells sampled in the caudal postero-medial LS area, the number of spikes was positively correlated with the peak eye velocities during ocular convergence. Significant correlation was found mostly within 400 ms preceding the moment at which the maximum velocity of ocular convergence was obtained. The result favors the hypothesis that the LS area plays an important role in the integrative control of ocular convergence.


Polyoma virus-induced murine odontogenic tumors. Neonatal mouse pups were injected subcutaneously with polyoma virus to induce odontogenic tumors. This treatment resulted in a spectrum of tumors that arose in organs dependent upon epithelial-mesenchymal interactions for their organogenesis, which included the teeth, salivary glands, thymus, and lacrimal glands. In addition, several odontogenic tumors with a histologic resemblance to ameloblastoma were identified and analyzed with respect to the presence of markers specific for various stages of ameloblast differentiation. Immunodetection analyses of the odontogenic tumors identified fibronectin and laminin, typical of basement membrane organization during early tooth organogenesis. These same tumors failed to express amelogenin, a gene whose expression is limited to differentiated ameloblasts. In contrast, a 47 kDa enamelin-like polypeptide was identified with the use of an antienamelin antibody. These data were interpreted to suggest that the polyoma virus truncated the differentiation pathway for these odontogenic tissues at an early stage of their development and retained the expression of basement membrane components and the enamelin-like polypeptides, yet excluded expression of amelogenin gene products. This observation suggests that polyoma viral transformation may dysregulate odontogenic tissue interactions and produce tumors composed of cells arrested at a specific stage in their development.


Effect of oxymetazoline nose drops on vascular permeability of the nasal mucosa in the rabbit after provocation with leukotriene B4. The effects of oxymetazoline nose drops on the vascular permeability of the nasal mucosa in a provoked inflammatory reaction was studied in anesthetized rabbits. Vascular permeability (125I-albumin) was 53% higher in the leukotriene B4-provoked nostril (LTB4) compared with the vehicle-treated contralateral nostril (p < 0.05). The amount of secretions was, however, not different from the vehicle-treated side. The LTB4-induced increase in permeability was decreased by 22% when oxymetazoline was introduced (p < 0.05), and the amount of secretions was reduced by 22% (p < 0.01). The effect of oxymetazoline on the vascular permeability of the nasal mucosa can be attributed to a vascular constriction (decrease in blood flow) and/or a change in the permeability characteristics. The LTB4-induced increase in vascular permeability was not attenuated by the monoclonal antibody IB4 directed against the neutrophil adhesion complex CD11/CD18. The latter suggests that LTB4-induced vascular permeability does not require CD18-mediated neutrophil adherence in the nasal mucosa.


[Reappearance of post-vaccination infection of measles, rubella and mumps. Should adolescents be revaccinated?]. Measles-mumps-rubella immunization has had a dramatic impact on the incidence of these diseases and their complications. However, a partial coverage, as seen in Belgium and France, only slows the spread of the wild virus, thus increasing the age at infection and the risk of complications. This is to be added to the fact that there are 5% primary vaccine failure (no antibody production) and 5% secondary vaccine failure (loss of antibodies over time). When introducing first immunization at 15 months of age it is thus very important to increase quickly the immunization coverage by immunization of all non-immune children entering school and by re-immunization of all teenagers.


[Acute kidney failure and nutrition].

[Acute kidney failure and nutrition]. Acute renal failure (ARF) is characterized by a persistently high mortality rate, mainly in prerenal, postaggressive forms. Nutritional perturbations are related to the metabolic response to stress, ie mainly an elevation of the basal caloric expenditure and a marked proteic hypercatabolism, and to specific consequences of the loss of renal function. Identification of characteristic metabolic patterns and of their mediators, leading to a nutritional support adjusted to the elevated demand rather than to the impairment of renal excretion faculties, may improve the prognosis. Benefits of such a nutritional support may be restricted to hypercatabolic forms of ARF in the intensive care unit, provided extrarenal failures are reversible.


[Congenital cysts and fistulae of the face and the neck]. The authors review the embryological, clinical and therapeutic aspects of congenital facial and cervical cysts (C) and fistulae (F), based on a personal series of 85 cases (facial: 18, latero-cervical: 29, mediocervical: 38) observed during a 5-year period. The facial forms are the result of an incomplete coalescence of the facial buds and most often present as helical F (17/18). Laterocervical C and F are due to abnormal evolution of branchial clefts; the main clinical forms are related to anomalies of the 2nd branchial cleft (24/29), usually presenting as sinus localized at the anterior border of the lower third of the sternocleidomastoid muscle (8) and amygdaloid cysts. Thyroglossal duct cysts are the most frequent of the medio-cervical C and F (35/38); they usually present as a mediocervical cyst in the thyro-hyoid space which may be revealed by an infection or a fistulization. The only appropriate treatment of congenital facial and cervical C and F is surgery providing that the resection is meticulous with complete resection of the fistula in order to avoid relapse. Complete resection also suppresses the risk of secondary malignant degeneration of amygdaloid and thyroglossal duct cysts.


[Vulvitis in young girls: value of cleansing base with concentrated colloidal oat extract]. Vulvitis is a frequent infection in young girls. Fourty prepubertal children with recurrent vulvitis were submitted, besides usual local hygiene rules, to a twice daily toilet with a cleansing base containing colloidal oat extract (Emulave fluid). It was associated with a colouring product in case of severe local inflammation during the first days of treatment. Minimal duration of the treatment was 15 days. In cases of long-term use, exceeding 3 months, no recurrence of local infection was observed. In all cases, tolerance was excellent.


[Parents' view on the care of their children at pediatric emergency department in 1991]. A survey carried out by questionnaire was performed among parents accompanying their children to the emergency department of the Lenval's children hospital in order to determine their opinion on the quality of the reception and care. The questionnaire was distributed to 2,382 parents. A total of 719 questionnaires (30.2%) were returned. A large majority of the parents (99%) expressed their satisfaction with the care and reception in the emergency department. The necessary improvements following this survey concern the duration of waiting prior to the consultation and the quality of the reception in the radiological and admittance departments; it is hoped that the radiological and admittance areas will be included within the emergency department, in the future.


[Activity of pediatric emergency departments in 1991]. The authors report the results of a prospective survey concerning the children examined in the pediatric emergency ward of the Lenval's hospital in Nice. The study was conducted over a period of 124 days, one month of each season, and included 3,611 children. There was a majority of boys (60.8%) and children older than 7 years (56.8%). The representation of foreign children was 11.2%. Most of the consultations were decided by the parents (86%); 6.2% were sent by a general practitioner and 1.1% by a pediatrician; 6.5% were conveyed through a professional public health service transport. Traumatology was the main surgical etiology and supplied the large majority of benign cases and 23% of the emergencies. Upper respiratory and bronchopulmonary tract infections and gastroenteritis represented 70% of medical etiologies. A complementary investigation, essentially a radiological examination, was carried out in 53.6% of cases. A wound suture was performed in 13% and a plaster immobilization in 9.2% of cases. The hospitalisation's rate was 22%. Emergencies represented 1.8% of cases. A surgical intervention with general anesthesia was performed in 4.4% of cases within 12 hours following the admission. A recent law (ministerial circular: 14.05, 1991) defines the organisation and working principles of the public emergency departments in France as requiring an uninterrupted activity, a continuous medical presence and an area for very short hospitalization. This should improve the quality of the pediatric emergency wards, providing that the financial means will be available.


[Your child is dead].

[Your child is dead]. To determine parents' views on how the death of their child should have been handled, a retrospective questionnaire survey was carried out among parents who had experienced the death of a child: 120 bereaved parents, all members of a charitable organisation of bereaved parents participated voluntarily in the study; 122 children's deaths were described; the largest single group was due to road traffic accidents, 16 were suicides, and eight were murders. Twice as many interviews were rated as sympathetically or reasonably handled than badly or offensively handled (68 vs 34). The interview ratings depended on the sensitivity and personal skills of the interviewers rather than on their previous contact or professional position; police were rated as more sympathetic than doctors and nurses. Of 109 respondents, 81 had seen their child's body, 44 of whom thought that sufficient time had been denied. Of the 28 parents who did not see the body, 17 subsequently stated their regret. In 82 parents, organ donation had not been discussed. Only 16 parents recorded any follow-up support from hospital staff and very few support at the time. The consistency of the responses suggests a serious need to revise the in-service training and education of the police and health professionals in their approach to informing of death; organ donation should be discussed sensitively and parents allowed time with their dead child with fewer restrictions.


Cytosolic Ca2+ spikes evoked by the thiol reagent thimerosal in both intact and internally perfused single pancreatic acinar cells. Cytosolic calcium signals evoked by the sulphydryl-group-oxidising agent, thimerosal, have been investigated in acutely isolated pancreatic acinar cells. Two techniques were employed for the assessment of the cytosolic free-calcium concentration ([Ca2+]i): measurement of calcium-dependent chloride and non-specific cation currents (whole-cell patch-clamp recording) and microfluorimetry (fura-2). Thimerosal (0.5-100 microM) evoked repetitive spikes in both chloride and cation currents as seen by patch-clamp recording, and in [Ca2+]i as seen by microfluorimetry, with a latency of 1-3 min. The response increased in magnitude over time and was not reversed on removal of thimerosal. The thimerosal-induced spikes were reversibly blocked by 2 mM dithiothreitol and by 20 mM caffeine. Inclusion of heparin (200 micrograms/ml) in the pipette solution blocked the thimerosal-induced spikes. The calcium spikes continued after the removal of extracellular calcium; however, low concentrations of thimerosal (0.5-5 microM) were unable to initiate a current response in the absence of external calcium. High concentrations of thimerosal (50-100 microM) could initiate spikes without extracellular calcium. Thimerosal, at concentrations that failed to produce an independent effect, potentiated the acetylcholine-evoked oscillations in [Ca2+]i. We conclude that thimerosal is able to mobilise calcium from an intracellular store; the blockade by heparin may indicate that thimerosal exerts an action on the inositol trisphosphate pathway. The dependence on extracellular calcium for initiation, but not for continuation of the thimerosal-induced calcium spikes suggests that thimerosal may have the additional effect of inhibiting the plasma membrane calcium ATPase.


Inhibitory serotonergic effects on rostral ventrolateral medullary neurons. In rats anaesthetised with urethane, iontophoretic application of 5-hydroxytryptamine (5-HT) and the 5-HT1A agonists buspirone, flesinoxan and 8-hydroxy-2-(di-n-propylamino)-tetralin inhibited ongoing or amino-acid-evoked activity of neurons in the rostral ventrolateral medulla (RVLM) including barosensitive cells with spinally projecting axons. More than 90% of cells tested were inhibited by these agonists. In 5/9 cells the inhibition was reduced after intravenous spiperone (0.6 mg/kg). These results suggest that the sympatho-inhibitory effects produced by microinjection of 5-HT1A agonists into the RVLM are due to a direct inhibitory action on neurons that send excitatory projections to the spinal sympathetic outflow.


An early outward transient K+ current that depends on a preceding Na+ current and is enhanced by insulin. A whole-cell early transient outward current occurs in rat myoballs if and only if there is an immediately preceding current of large amplitude through the voltage-gated, tetrodotoxin-inhibitable Na+ channel. This early outward transient is a K+ current, designated IK(Na+). Under the conditions in which IK(Na+) appears, simultaneous measurement of voltage and current, under voltage clamp, demonstrates that there is transient voltage escape to depolarized levels, peaking at about the time of peak inward Na+ current and resembling an action potential. IK(Na+) was never seen in the absence of this breach of the voltage clamp, suggesting that IK(Na+) might be an artefact due to transient depolarization from the clamp. However, when the voltage escape was mimicked by voltage commands under conditions in which the Na+ channel was not activated, there was no IK(Na). Insulin increased or produced IK(Na+) even though insulin had no effect on INa or on the delayed rectifier K+ current or on the escape from voltage clamp. It is concluded that there is a population of rat myoballs in which there is an early outward K+ current that requires an immediately preceding current through the voltage-gated, tetrodotoxin-inhibitable Na+ channel and is enhanced by insulin.


Intracellular protons inhibit inward rectifier K+ channel of guinea-pig ventricular cell membrane. The effect of intracellular protons (Hi+) on the inward rectifier K+ channel of the guinea-pig ventricular cell membrane was examined, using the patch-clamp technique. The inward single-channel current was recorded in "inside-out" and "outside-out" patch configurations, while the pH of the solution perfusing the intra- and extracellular side, respectively, was varied. Low intracellular pH (pHi), but not low extracellular pH, inhibited the channel. Low pHi reduced the unit amplitude, which was about 20% smaller at pHi 6.0 than that at pHi 7.4 at every voltage tested. The slope conductance decreased from 41.7 pS at pHi 7.4 to 35.1 pS at pHi 6.0. Low pHi also reduced the channel activity without apparent voltage dependence. The concentration/response curve indicated the half-maximum inhibition at pHi 6.11 and a Hill coefficient of 2.52. Lowering the pHi from 7.4 to 6.0 did not affect the distributions of the open times and the closed times below 50 ms, while the time constant of the histogram constructed from closings longer than 50 ms was approximately doubled. These results indicate that the inward rectifier K+ channel in ventricular myocytes is inhibited by H+ from the intracellular side. This might contribute to the depolarization of the resting membrane potential induced by intracellular acidosis during myocardial ischaemia.


[Effect of opioid receptor blockade with naloxone on vasopressin secretion in patients with transplanted kidney]. The present study aimed to assess the influence of opioid receptors on vasopressin (AVP) secretion in 12 kidney transplant patients (KTP) with stable graft function, and in 15 healthy subjects (control). Significantly lower basal plasma AVP levels were found in KTP than in controls. After blockade of opioid receptors by naloxone a significant increase of plasma AVP levels were observed in both examined groups. This increase was significantly higher in KTP than in healthy subjects. From data presented in this study participation of opioid receptors in the regulation of AVP secretion is highly likely both in KTP and controls. This participation seems to be significantly greater in KTP than in healthy subjects.


Kinetic modeling of ouabain tissue distribution based on slow and saturable binding to Na,K-ATPase. The significance of the binding to Na,K-ATPase in the tissue distribution of ouabain was previously documented (Harashima et al., Pharm. Res. 9:474-479, 1992). The purpose of this study was to obtain a kinetic model of ouabain tissue distribution. In most tissues, the ouabain concentration continued to rise after the termination of infusion (5 min), with the peak tissue concentration at approximately 20 min. This delay could not be explained by the rapid equilibrium model (RE model), nor could the kinetics of ouabain be explained by an RE model modified for saturable binding. Since ouabain binding to Na,K-ATPase is slow, the association and dissociation processes were incorporated into a model that can accurately fit the observed time courses of ouabain. The obtained binding parameters corresponded well with the observed values in the in vitro binding experiments, except for muscle. These results quantitatively support the role of the slow and saturable binding of ouabain to Na,K-ATPase in its tissue distribution.


Dynamic SPECT imaging after injection of the benzodiazepine receptor ligand [123I]iomazenil in healthy human subjects. Previous work suggests that iomazenil (formerly known as Ro 16-0154) is a useful ligand for static imaging of the benzodiazepine (BZ) receptor with single photon emission computed tomography (SPECT). The present study evaluated the feasibility of dynamic SPECT imaging of cerebral radioactivity following intravenous [123I]iomazenil injection in healthy human subjects, in preparation for future receptor quantitation studies. Maximal brain uptake was reached approximately 25-30 minutes after i.v. administration of the radioligand and represented approximately 12% of the injected dose. The regional distribution of radioactive densities was consistent with the known distribution of BZ receptors in human brain, with highest uptake localized over the occipital area. Washout of cortical radioactivity was regionally variable but relatively slow, with a half-life of approximately 4 hours after the time of peak radioactivity. In summary, [123I]iomazenil is a promising SPECT radioligand for the BZ receptor, with high brain uptake, relatively slow washout of radioactivity, and appropriate regional distribution.


[Sphenoidal hyperostosis. Problems of differential diagnosis: report of a case]. A case of sphenoid hyperostosis is described in a patient whose clinical history and radiological work up suggested fibrous dysplasia. A year later, the biopsy and MRI showed evidence of a meningioma en plaque. Problems in the differential diagnosis are discussed among entities which present sphenoid hyperostosis: osteoma, Paget's disease, sphenoid meningioma and fibrous dysplasia.


[Static and dynamic scintigraphy of the liver using labeled erythrocytes in the diagnosis of hepatic hemangioma]. In order to find hemodynamic differences between hemangioma (n = 10) and other tumours of the liver (n = 15) dynamic angioscintigraphy and late vascular scintigraphy of the liver were performed. Late vascular scintigraphy has revealed focal cumulation of the labelled erythrocytes in 7 hemangiomas of the diameter of 35 mm, 3 hemangiomas below this size have not been diagnosed with this technique. Beside hemangiomas, a focus of erythrocytes cumulation was found also in the hepatocellular adenoma. Arterial blood supply to hemangioma was significantly higher, than that in the malignant tumours of the liver (54.6% vs 31.7%). Other parameters of the early phase of angioscintigraphy have no diagnostic value in the differentiating the hepatic tumours. Vascular scintigraphy of the liver proved to be a valuable technique in the diagnosis of large hemangiomas only.


[Occult bronchial carcinoid tumor producing ACTH simulating Cushing's syndrome]. Cushing's Syndrome raises sometimes important diagnostic and therapeutic problems. A case of Cushing's Syndrome is discussed, induced by ectopic secretion of ACTH by a Benign Bronchial Carcinoid Tumor, which due to its clinical features (asymptomatic and invisible to conventional radiology and associated with typical signs of Chronic Hypercortisolism) and biochemical findings (ACTH only slightly raised and suppression with high doses dexamethasone), simulated an hypophyseal origin, the pulmonary tumor being showed only after 3 years of the diagnosis of Cushing's Syndrome.


[How can the anatomic mediastinal extension of the tumor be estimated? Endoscopic evaluation]. Tracheobronchial endoscopy is more particularly designed for the exploration of endotracheal and bronchial lesions. However, involvements of the mediastinum can be suggested or demonstrated on the basis of generally indirect signs. The most classical example is the paralysis of the left vocal chord, which expresses a para- or subaortic mediastinal extension. Tracheobronchial endoscopy has an interesting but not determining role in the appreciation of the mediastinal extension of non-small-cell bronchial cancers. It most often allows guiding complementary radiological examinations, and sometimes provides histological evidence of mediastinal extension. In some cases, esophageal endoscopy can demonstrate mediastinal extension, if a tracheoesophageal tumor is discovered.


[Bronchial cancer: how can the anatomic mediastinal extension of the tumor be estimated?]. Determining the precise extension of a bronchial carcinoma is essential to decide the treatment and appreciate the outcome. Computed tomography (CT) remains the reference method for the evaluation of mediastinal invasion by tumor. It seems reasonable to purpose CT for every operable tumor after radio bronchoscopic examination (except for peripheral T1 tumor without contact with the pleura). The place of MRI is not yet definitely established. But one can expect it to be better defined in the years to come because of technical improvement. However MRI could be performed in place of CT or complementary to CT in some cases: tumor of pulmonary apices, tumor in contact with diaphragm cardiac cavities or large mediastinal vessels, suspicion of vertebral invasion. MRI is also indicated first in cases of contra indication to iodine injection. There is no more indication to angiographic examinations for the staging of bronchogenic carcinoma. Other imaging methods have to be evaluated in this field: i.e. esophagoscopy, endovascular, ultrasound or angioscopy.


[How can the extension of lung cancer to the osteo-muscular wall of the diaphragm, the pleura and the apex be assessed radiologically?]. The merits of evaluating the parietal extension of lung cancers is emphasized by the new TNM classification. CT and MRI have added to the conventional radiological techniques. The authors successively analyze the contribution of these techniques to the assessment of extension of lung cancers to the wall, including the costal and phrenic compartments, to the pleura and to the apex. Lung radiographs show obvious lesions, such as extensive costal lysis and major pleural extensions. Computed tomography has better sensitivity and specificity than lung radiographs to establish pleuroparietal involvement; it is best performed in the inclined plane of the ribs and in the high-resolution mode. The presence of costal lysis means parietal involvement, while the integrity of the pleura can be established if the lesion remains at a distance from the wall. The persistence of an extrapleural fatty rim between the tumor and the wall allows ruling out parietal extension. MRI provides accurate details in case of doubtful CT findings for the extension to the costovertebral groove, to the intervertebral foramina, to the peridural space and to the diaphragm. Its major asset is to assess the vertebral, vascular and nervous extension of cancers of the apex pulmonis.


[What is the role of thoracoscopy in the preoperative staging of non-small cell bronchial cancer?]. It is of paramount importance to clearly separate the non small cell bronchogenic cancers involving the chest wall or the diaphragm (T3) and those metastasizing to the pleura (T4). In both events, surgery is either technically demanding or contraindicated. What is the contribution of thoracoscopy to diagnosis? Very few authors have used thoracoscopy in a restricted number of cases and with varying results to confirm tumoral extent to the chest wall. We are of opinion that this approach is only warranted in patients at major operative risk, in order to prevent an unprofitable thoracotomy. Concomitant pleural effusion as indication for thoracoscopy should be discussed with respect to the following data: 1) Among all bronchogenic cancers, 10% present with a concomitant pleural effusion detected on chest radiograms, 60% of which are metastatic. The significance of effusions disclosed by CT scan has not yet been established. 2) Pleural involvement inconsistently produces an effusion; the prevalence compiled from thoracotomies is varying according to the authors. 3) The sensitivity of thoracoscopy for the positive diagnosis of malignant effusions is about 95%. The concomitant pleural effusion is predictive of poor prognosis, but does not preclude operability. Cytology of thoracentesis specimens and pleural needle biopsy are the consistent first steps towards diagnosis; thoracoscopy should be restricted to the failures of these techniques.


[How can intrathoracic lymphatic involvement be assessed: does tomography have a role? What is the contribution of computed tomography and MRI?]. The authors report their analysis of the literature on the evaluation of intrathoracic extension of non-small-cell bronchial cancers to lymph nodes, using tomography, computed tomography and magnetic resonance imaging. The criteria used to assess the metastatic character of a lymph node, the characteristics of the populations studied and the methods of comparison with the clinicopathological "truth" account for the variations of the results published. Tomographs are useless today. The performances of CT and MRI are equivalent, and it is not necessary to associate both techniques. Although its performances are mediocre, CT allows mapping the mediastinal lymph nodes, which is useful to continue the assessment of extension and to make decisions.


[How can intrathoracic lymphatic involvement be assessed using mediastinoscopy in primary bronchial cancer?]. In order to achieve mediastinal lymph node staging in bronchial cancer, axial mediastinoscopy (combined with left anterior mediastinoscopy for cancers of the left upper lobe) is by far the most efficient and the most reliable technique. Since mediastinoscopy has been part of the investigations that can be made before thoracotomy, the number of exploratory thoracotomies has considerably decreased in all teams, thus reducing at the same time intraoperative mortality. Thoracic CT, which arrived in the diagnostic weaponry for lung cancer a long time after mediastinoscopy, has a major asset in that it allows selecting the patients for whom mediastinoscopy seems to be useful, on the basis of criteria related to the size of mediastinal lymph nodes (10 mm generally being the threshold chosen to perform mediastinoscopy or not). For almost all authors, systematic mediastinoscopy is no longer useful. Similarly, a positive mediastinoscopy must not lead to systematically refuse patients, as the invasion or absence of invasion of a mediastinal lymph node is neither necessary nor sufficient to discuss a surgical indication. While some still automatically refuse all patients with positive mediastinoscopy, most authors still remain very interventionistic for N2 patients selected on very accurate criteria that are analyzed above. Surgery can then be performed at once or, for some authors, after a "neo-adjunctive" therapy, the long-term efficacy of which has unfortunately not been rigorously demonstrated as yet.


[Evaluation of intrathoracic lymphatic involvement: the role of mediastinoscopy]. Mediastinoscopy is a technique that allows palpating, inspecting and puncturing the lymph nodes of the upper mediastinum. When this examination is performed as a routine in patients with a supposedly operable lung cancer, the positiveness rate is 25-30% and most subjects become inoperable because of the extent of invasion. The specificity of mediastinoscopy is of 100%, and it ensures that no potentially operable patient shall be refused for curative surgery. Anterior mediastinoscopy and extensive cervical mediastinoscopy are complementary techniques, which allow exploring the anterior mediastinum in patients with a cancer of the left upper lobe. In experienced hands, these techniques are safe and cause little or no morbidity.


[Evaluation of mediastinal lymphatic involvement]. The analysis of extension to mediastinal lymph nodes during the initial assessment of primary bronchial cancers relies on computed tomography, MRI and mediastinoscopy. Two reports of the consensus conference analysed the respective sensitivity and specificity of these three techniques. The impact of these examinations on the survival of the patients undergoing them is difficult to measure. The successive introduction of these techniques into daily practice has not been analysed in terms of impact on survival. Randomized studies in homogeneous groups of patients of the influence of examinations such as mediastinoscopy on survival are lacking today. While computed tomography has become essential, mainly because it is easy to use and allows re-reading, mediastinoscopy remains an examination for which the indications are controversial according to the schools.


[How can metastatic extension be assessed in the brain?]. MRI is the technique of choice to detect cerebral metastases. Double-dose delayed CT is the optimal CT examination to be performed in case of limited access to MRI. If the examination shows the presence of multiple metastases, MRI is not necessary. If CT shows an apparently single lesion, an MRI examination is essential, considering the number of lesions detected by MRI and not seen with CT.


[How can metastatic bone involvement be assessed?]. The first intention imaging modality for detecting bone metastases of non small cell (NSC) bronchogenic carcinoma is bone scintigraphy using technetium-99m pyrophosphate or diphosphonates. This test has a high sensitivity but equivocal images may lead to complementary tests including magnetic resonance imaging (MRI) or bone biopsy. Based on bone metastases prevalence, scintigraphy is recommended for patients entering a therapeutic trial, having bone pain, having a non characteristic bone abnormality on radiography or CT, having a non epidermoid histology or having associated pathologies increasing the risk of surgery. The utility of bone scan is questionable for patients having a Stage I or II epidermoid cancer, having already evidence of bone metastases or for whom the result of the bone scan will not change the therapeutic management. After a negative bone scan, there will be probably an indication for MRI at search of small infra-scintigraphic osteo-medullary metastases.


[Evaluation of metastatic liver and adrenal involvement in the pre-therapeutic staging of non-small cell bronchial cancer]. The evaluation of infra-diaphragmatic extension to the liver and the adrenal of non oat-cells bronchogenic carcinoma, is indicated to select the patients which may be operated. Thin slices (5 mm) on the adrenals have to be performed on the initial thoracic computed tomography, as ultrasonography (US) and MRI are less accurate. The exploration of the liver by US used as first imaging modality, may induce some false negative results, with useless surgery, and may be replaced by a CT of adrenal and liver. MRI doesn't seem actually without adapted contrast agents, significatively more efficient than CT, to detect metastases of the liver or adrenals.


[Lung metastasis].

[Lung metastasis]. Pulmonary metastasis of non small cell lung carcinomas are commonly nodular. The isolated nodular form must be diagnosed from double location carcinomas. The lymphangitic carcinomatosis semiology is best demonstrated with HR-CT-Technic. Endobronchic, alveolar and multi-micro angiopathy with emboli are less common.


[The role of tumor markers in the pre-therapeutic staging of non-small cell bronchial cancer]. A biological cancer marker is a molecule, synthetized from a neoplastic tissue, which is present in the tumor and can be detected in measurable amounts in circulating blood. The natural history, prognosis, heterogeneity of each tumor and the histology of bronchial cancers clearly show the difficulty to establish the role of markers in the management of these tumors, especially for the initial assessment of extension. The analysis of the literature shows that studies on this subject are rare. The use of an isolate marker is not sufficient for a positive diagnosis of non-small-cell bronchial cancer. The use of several markers produces better results. However, no model is accurate enough to formally influence the diagnosis of operability. No isolate or associated marker allows differentiating between small-cell and non-small-cell bronchial cancers. The most interesting two markers finally seem to be ACE and CA 125. All other markers must not be used as a routine during the assessment of non-small-cell bronchial cancers. However, these markers are still important for therapeutic follow-up. Even though they are not predictive of chemosensitivity, and even though their decrease is not regarded as an objective criterion of response, their variations are linked with the response to chemotherapy, and their persistent normalization after surgery is compatible with apparent complete remission. The ACE and CA 125 assays can therefore be used as a reference, in case of initial positive findings, for the subsequent follow-up of the patient.


[Do clinical and non-specific biological data influence staging?]. Recent improvements in imaging technics have led many physicians to propose an extensive work-up in non small cell lung carcinoma (NSCLC) without clear impact on the therapeutic decisions. In fact, it appears that patients with operable disease (stage I, II NSCLC) do not clearly benefit of such complete assessment in absence of symptoms. In the same way, patients with established metastatic disease (stage IV NSCLC) do not require an extensive work-up except when the evidence of a metastatic lesion has a clear specific impact. On the other hand, in case of locally advanced disease (stage III NSCLC), the decision of an aggressive therapeutic approach including surgery, radiotherapy and chemotherapy justify a complete assessment in order to control the lack of distant metastases.


[Do pathologic-anatomic data influence the staging of non-small cell bronchial cancer?]. The histopathology criteria which could be taken into account in devising the best strategy in tumor extension search in non small cell lung carcinoma (NSCLC), were examined. First, the differential diagnosis between primary and metastatic carcinoma is impossible on histological basis in squamous carcinomas, and in mucinous adenocarcinoma which share several features with tumors from digestive tract including mucus secretion, morphological pattern and ultrastructural signs. The recognition of cells which are unique in the lung (Clara cells, pneumonocytes II) guarantees the pulmonary origin of a non mucinous adenocarcinoma. In other cases such as large cell carcinomas, the diagnosis of metastasis can be achieved in some instances in using a large panel of immunohistochemical markers. Secondly, the expression of neuroendocrine markers in NSCLC could lead to an extension search procedure identical to that of SCLC, if it can be confirmed that they share their poor prognosis and chemosensibility. Finally, there is no statistical evidence of a difference in the extrathoracic extension between well and poorly differentiated forms of squamous carcinoma and adenocarcinoma. Only one exception should be made for the recently described basaloid carcinoma of the lung which extension and prognosis are more severe than in other NSCLC.


Unusual structure of plasmid DNA formed in transformants of Escherichia coli. An unusual structural component of plasmid pUC18 was observed in transformants of Escherichia coli strains. This molecule migrated faster than superhelical topoisomers in agarose gel electrophoresis and was difficult to stain with ethidium bromide. This unusual topology appeared independently of gyrase mutation, and the recA genotype may relate to accumulation of the plasmids conforming to the unusual topology.


Catecholamines during cardiopulmonary resuscitation for cardiac arrest. Serum catecholamines were measured during continued prolonged cardiopulmonary resuscitation and after 10 mg increments of intravenous epinephrine. This was part of an ongoing trial of 10 mg epinephrine versus placebo. Eight patients were in the placebo arm and seven in the epinephrine arm and the rhythms were two ventricular fibrillation, nine asystole and four electromechanical dissociation. Data were analysed by time from onset of the cardiac arrest and samples were analysed for levels of DHPG (dihydroxyphenylglycol) nor-epinephrine, epinephrine, DOPA (dihydroxyphenylalanine) and DOPAC (dihydroxyphenyl acetic acid). There was a significant (P < 0.001) difference between arterial and venous samples of epinephrine but not the other catecholamines. High levels of catecholamines were maintained in all time phases except for nor-epinephrine where significant (P < 0.0003) reduction occurred progressively after 20 min. Non-steady state kinetics were suggested between epinephrine and nor-epinephrine and DHPG and nor-epinephrine for the first 20 min. Very large increases in epinephrine were achieved with administered 10 mg epinephrine and this resulted in high DHPG levels supporting the experimental belief that exogenously administered epinephrine induces myocardial release of nor-epinephrine. This data supports the known effects of CPR on catecholamine release. It provides data on the other neurotransmitter hormones and supports the relationships shown in other animal and human data. It is suggested that supplementation with epinephrine during CPR may be unnecessary and the levels reached may be deleterious. Nor-adrenaline supplementation may be necessary after prolonged CPR.


Sequential change of heterogeneous cerebral blood blow patterns after diffuse brain ischemia. In order to provide an insight into the basic nature of ischemic brain injury, we sequentially studied cerebral blood flow with [99mTc]hexamethylpropyleneamine oxime single photon emission computed tomography (CBF imaging) in a patient with diffuse brain ischemia due to prolonged cardiac arrest. On the 10th postarrest day, concentrated blood flow over superior-medial portion of the occipital lobe was demonstrated. On the 18th postarrest day, the same region became high density on a CT scan, while the concentrated flow on the CBF imaging had diminished. Thus, an abnormal cerebral blood flow (CBF) pattern preceded the density change on CT scan. On the 23rd postarrest day, remarkably concentrated flow over the brainstem was demonstrated. This might have illustrated the reduced metabolic demand of the damaged tissue over the cerebral and cerebellar hemispheres with relative preservation of brainstem perfusion. In patients with diffuse brain ischemia, a CBF imaging may be a useful tool for clarifying pathological process and prognosis.


Reactive oxygen metabolites in inflammation. The functions of professional phagocytes depending on oxygen are briefly discussed. After appropriate stimulation, membrane-bound enzyme systems are activated--phospholipase C, protein-kinase C and NADPH-oxidase complex--and superoxide anion is produced. This process is called respiratory burst and is essential for killing of microorganisms but it may cause tissue damage and inflammation. The influence of superoxide anion on metabolism is reviewed. More attention is paid to modulating effects of superoxide anion in connection with the development inflammatory process.


Effect of insulin on permeability of lysosome membrane in primary monolayer hepatocyte culture of newborn rats under anoxia conditions. The influence of insulin was studied in the monolayer hepatocyte cultures of newborn rats during anoxia. Insulin (1 x 10(-4) U ml-1) caused a significant increase of acid phosphatase activity in the lysosome-rich subcellular fraction after 20 min exposure of the cells to anoxia and also in experiments in which hepatocytes were incubated with insulin for 1 h in normoxia followed by exposure to anoxia for 20 min. The data obtained suggest that insulin had a stabilizing effect on lysosomal membranes when exposure to insulin was prolonged. On the other hand, insulin caused a more-than 2-fold increase in cAMP content in hepatocytes in a 2 min exposition when compared to control cultures. When exposition of the cells to insulin lasted for more than 2 min, lowering of cAMP content was observed. The data seem to indicate that the stabilizing effect of insulin on lysosomal membrane was secondary to the increase in the cAMP level. From the above evidence and that accumulated by others we conclude that there may exist an indirect connection between the cAMP level, insulin stabilizing action, and the state of lysosomal membranes.


Azithromycin pharmacokinetics and penetration to lymph. The study of pharmacokinetics of azithromycin and penetration to peripheral human lymph was carried out in 14 healthy male volunteers taking 1 g orally after overnight fasting. Samples were analyzed by microbiological assay. The mean peak concentrations were 0.82 +/- 0.23 mg/l after 1.7 +/- 0.5 h in serum and 0.22 +/- 0.07 mg/l after 3.1 h in lymph. Nine of the 14 subjects showed a second and lower serum peak indicating the existence of enterohepatic circulation. The total areas under the serum concentrations curves (AUCs) till infinity were 7.9 +/- 3.1 mg. h/l compared to 4.4 +/- 1.2 mg.h/l in lymph. The mean lymph AUC was 68.1 +/- 20.7% of the serum AUC indicating a penetration ratio of 0.68. However, the actual amounts penetrating the tissues were much higher than this ratio suggests. Thus, after 6 h 81% of the drug was within the tissue compartment and after 120 h, 63% of the azithromycin was still present in the tissue compartment. The urinary recovery of azithromycin was 14.7 +/- 7.7% during the first 48 h. The serum curves and lymph curves displayed a distinctly slower phase of elimination after 12 h. The mean serum half-life was 5.4 +/- 3.4 h during the first 12 h (after the peak), whereas the value was 44.2 +/- 10.1 h during the interval 12-120 h. The corresponding half-life values for the peripheral lymph were 5.4 +/- 2.2 h and 50.8 +/- 11.6 h. Azithromycin possesses key pharmacokinetic properties that are prerequisites for a convenient once-daily dosage schedule which may improve patient compliance.


Changes in calcanean bone mineral occurring spontaneously and during hormone replacement therapy in early post-menopausal women. The spontaneous calcanean bone loss occurring in healthy early post-menopausal women and the effect of two hormone replacement therapies (HRT's) were investigated in a longitudinal study. There was no difference between the right and left calcanean BMC or BMD (p > 0.15). The spontaneous bone loss was similar at all the skeletal sites measured, with a mean spontaneous loss in calcanean BMD of 1.6% over one year. Both HRT's significantly (p < 0.01) prevented the bone loss from all skeletal sites irrespective of the weight-bearing or content of trabecular bone, and (for the weight-bearing bones) there was even a gain in calcanean BMC and BMD and spinal BMD (p < 0.01). Bone mineral of the calcaneus and the spine correlated equally to body weight (r approximately 0.4, p < 0.001), whereas bone mineral in the forearm was not correlated to body weight. The correlations between the changes in bone mineral at the sites measured were all significant (r approximately 0.2-0.4).


Azithromycin in upper respiratory tract infections: a clinical trial in children with otitis media. Azithromycin is a newly developed azalide antibiotic which is very active against microbes causing respiratory tract infections; tissue concentrations remain elevated for a long time after discontinuation of treatment. A clinical study was conducted to compare azithromycin (10 mg/kg administered as a single daily dose for 3 days) with amoxycillin/clavulanic acid (50 mg/kg/day given b.i.d. for 10 days) in 30 children with otitis media. Sensitivity testing demonstrated good azithromycin activity against beta-haemolytic streptococci, Moraxella catarrhalis, Haemophilus influenzae and Staphylococcus aureus. By day 12, clinical cure was recorded in 14/15 children treated with azithromycin and this was maintained at day 30. In the day 12 and 13/15 children by day 30. It was concluded that a 3-day azithromycin regimen produces a satisfactory clinical response and the eradication of key pathogens, and was acceptable for children.


Azithromycin in lower respiratory tract infections. Azithromycin is a new azalide antimicrobial agent which has a broad spectrum of activity against common lower respiratory tract pathogens including pneumococci, staphylococci, Legionella species, Mycoplasma and Chlamydia species. In particular, it is more active against Haemophilus influenzae than other macrolides. In comparison to other new macrolides, azithromycin achieves higher tissue and intracellular concentrations and these concentrations are sustained for several days after dosing due to a long elimination half-life. The efficacy of azithromycin against lower respiratory tract infections has been proven in several clinical studies. Once-daily dosing with azithromycin, over a 3- or 5- day period was as effective as a 10-day course of other commonly used antibiotics such as amoxycillin/clavulanic acid, erythromycin or cefaclor in lower respiratory tract infections. Azithromycin short-course therapy may offer an advantage in terms of patient compliance and the duration of treatment.


A European head injury evaluation chart. In 1988, 40 experts (physicians, psychologists, social workers, lawyers, family association representatives...) coming from the E.E.C., the United States, Canada and Sweden met in Brussels to derive the guidelines for a minimal assessment of head injured people. This workshop led to a research contract between E.B.I.S. (European Brain Injury Society) and the E.E.C. Directorate for Science regarding a European evaluation document. The aims of the document are both clinical and scientific. Hence the document has to be simple, specific and feasible. The document has two parts: initial state and repeated follow-up. It ends with final comments and action plan. The first statistical data of the validation study concern mainly the link between initial severity of injury and final handicap, cognitive and behavioural troubles, familial and professional aspects of handicap.


Combination chemotherapy with oral etoposide. Chronic administration of etoposide over multiple days has proved to be an effective schedule against a variety of neoplasms. The usual duration of etoposide administration is 3 to 5 days. However, recent studies have demonstrated this agent can be administered for up to 21 consecutive days with acceptable toxicity. Studies are currently under way to determine whether more protracted etoposide administration will prove to be more efficacious in the management of selected malignancies. Previous work at our institution has confirmed the activity of protracted administration of single-agent etoposide against small cell lung cancer and non-small cell lung cancer. More recently, we have combined either cisplatin or carboplatin with etoposide given orally for 21 consecutive days in phase II trials in patients with small cell lung cancer and non-small cell lung cancer. The results of these trials are reviewed.


Chronic oral etoposide in the treatment of lung cancer. Etoposide is used commonly to treat both small cell lung cancer and non-small cell lung cancer. It is usually administered intravenously over 3 to 5 consecutive days, and usually given in combination with cisplatin. Preclinical cellular and clinical pharmacokinetic studies have demonstrated that etoposide is schedule-dependent and is optimally administered at low doses over prolonged periods of time. Recent early phase clinical trials have demonstrated that oral etoposide can be administered safely for 14 to 21 consecutive days. This schedule has demonstrated outstanding activity in patients with both recurrent and previously untreated small cell lung cancer. Activity against non-small cell lung cancer has also been reported; response rates are similar to those seen with the most active single agents used in the treatment of the disease. Chronic oral etoposide also has the advantages of outpatient convenience and tolerable side effects. This overview discusses the role of chronic oral etoposide in the management of small cell lung cancer and non-small cell lung cancer. The scientific rationale, results of early phase clinical trials, ongoing research, and future directions regarding the chronic administration of this important antineoplastic drug are also reviewed.


The activity of 10-, 14-, and 21-day schedules of single-agent etoposide in previously untreated patients with extensive small cell lung cancer. Pharmacologic studies in patients with small cell lung cancer treated with differing schedules of intravenous etoposide over 1 to 8 days have suggested that etoposide's antitumor cytotoxicity is related to duration of exposure to low plasma levels of drug. Three phase II studies have been performed in 78 patients with extensive small cell lung cancer examining the efficacy and toxicity of 50-mg doses of oral etoposide given twice daily for 14 days every 3 weeks, once daily for 21 days every 4 weeks, and twice daily for 10 days every 3 weeks. Partial response rates were observed in 76%, 52%, and 70% of patients, respectively. Median response duration appeared similar in all three schedules, but the time to achieve a response appeared longer in the 21-day, once-daily schedule. Bone marrow toxicity was generally mild, but occasionally severe nadir blood counts were observed. These studies demonstrate that prolonged administration of low-dose oral etoposide is very active in small cell lung cancer, and that a twice-daily regimen is preferable in view of the greater rapidity of response and possibly higher response rate. The optimal duration of a twice-daily, 50-mg dosage schedule remains to be determined.


Oral etoposide in small cell lung cancer. Small cell lung cancer (SCLC) accounts for 25% of all cases of lung cancer diagnosed in the United States. The sensitivity of SCLC to chemotherapy offers good prospects for prolonged remission and long-term survival. Over the last decade, however, the overall response rate and median survival in SCLC patients have remained essentially unchanged. Single-agent intravenous (IV) etoposide has proven to be among the most active drugs for the treatment of SCLC. Oral or oral plus intravenous etoposide has been used in many combination chemotherapies. Studies demonstrating the schedule dependency of etoposide suggest that optimum results would be achieved if the total were administered over a minimum of 5 days. Given in such a schedule, oral etoposide has been shown to be effective in unfit or elderly (> 70 years of age) patients with SCLC, who represent 25% to 30% of the total SCLC population. Prolonged etoposide administration has achieved efficacy comparable with that attained in 5-day schedules, but with notable toxicity. Moreover, the value of dose intensity in single-agent and combination regimens employing etoposide has recently been questioned. New therapeutic strategies are clearly needed to increase the response rate, to prolong survival, and to improve quality of life in SCLC patients.


Chronic oral etoposide: trials at Indiana University and with the Hoosier Oncology Group. Etoposide has proven to be an active agent in the treatment of a variety of neoplasms, particularly germ cell cancers and small cell lung cancer. Yet despite its widespread use, the optimal dose and schedule for etoposide remain unknown. The fact that its efficacy appears to be schedule dependent, along with the recent availability of an oral formulation, formed the basis for several trials at Indiana University and through the Hoosier Oncology Group. These trials evaluated chronic daily administration of the drug in several malignancies. In testicular cancer, etoposide was shown to have a possible role in adjuvant therapy for refractory disease or as part of combination chemotherapy. In small cell lung cancer, etoposide demonstrated activity in both previously treated and untreated patients. The drug, however, had little impact on patients with advanced non-small cell lung cancer, advanced melanoma, or advanced soft tissue sarcoma. Since etoposide appears to be most effective in refractory small cell lung cancer and germ cell tumors, we believe the drug should be explored in tumors with a known history of chemosensitivity to conventionally administered etoposide.


Abnormal erythrocyte Na, K-ATPase activity in a northeastern Thai population. We studied the cellular membrane enzyme responsible for potassium transport in different Thai populations. We measured plasma and intraerythrocytic concentrations of sodium and potassium, activities of erythrocytic membrane Na, K-activated adenosine triphosphatase (Na, K-ATPase), ouabain-insensitive ATPase, total ATPase and the activity ratio of Na, K-ATPase/total ATPase in 25 healthy blood donors at Khon Kaen University Hospital, Khon Kaen (group 1), and in 32 donors at the National Blood Center, Thai Red Cross Society, Bangkok (group 2). Group 1 subjects had significantly higher concentrations of erythrocyte sodium (p < 0.001) and lower activity of Na, K-ATPase (p < 0.001) than group 2. When data of these 2 groups were combined, erythrocyte Na+ correlated inversely with Na, K-ATPase and the activity ratio of Na, K-ATPase/total ATPase. Our study suggests that there is a defect in membrane transport enzymes for sodium/potassium in certain northeast Thai populations.


A skin-specific MMTV provirus is stably transmitted by horizontal transmission. Mouse mammary tumor virus (MMTV) is a retrovirus with a life cycle that remains to be elucidated. In establishing Mtv-4 congenic mice, an extra copy of the MMTV provirus was found specifically in the skin of both sexes of SHN mice but not in C3H/He mice. This extra copy was not, however, found in other normal tissues such as brain, lung, liver, spleen, kidney, uterus, testis, and mammary glands from SHN or C3H/He mice. In the skin of SHN mice, an 11-kb DNA fragment, which approximates in size to the entire MMTV genome, was detected in undigested high-molecular weight DNA. This unique MMTV provirus was shown to be transmitted horizontally from SHN mice to exogenous-MMTV-free C3H/He mice through nursing. The virus is thus concluded to be exogenous. Clusters of MMTV type A particles were found in sebaceous glands by electronmicroscopic examination. The present findings indicates that exogenous MMTV may be stably maintained in the skin as an unintegrated provirus during its life cycle.


Effect of omeprazole on ascorbate free radical formation. In order to study the effect of omeprazole on the K/[H+] value of ascorbic acid (K = the ascorbic acid-ascorbic free radical equilibrium constant), changes of the concentration of ascorbate free radical in guinea pig sera were examined after intraperitoneal administration of omeprazole. Furthermore, to see the in vitro effect of omeprazole on ascorbate free radical, changes were examined in ascorbate solutions after addition of omeprazole. It was found that the K/[H+] value in the serum increased significantly after administration of omeprazole and also that the drug amplified the electron spin resonance (ESR) signal intensity of ascorbate free radical in vitro. These results suggested that omeprazole acts like oxygen radicals.


Treatment results by uneven fractionated irradiation, low-dose rate telecobalt therapy as a boost, and intraoperative irradiation for malignant glioma. The prognosis of malignant glioma is extremely poor. We applied conventionally fractionated irradiation combined with 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea (ACNU), uneven fractionated irradiation with ACNU, low dose rate telecobalt therapy as a boost, and intraoperative irradiation against 110 malignant gliomas to investigate the efficacy of these methods as alternative treatments for malignant glioma. Although local tumor control by uneven fractionated irradiation was better than that by the other methods, no significant improvement was obtained in survival rates. As a result of multiple regression analysis, age and histology were major factors for survival rates, and the difference of treatment methods was not important. Both low-dose rate telecobalt therapy as a boost and intraoperative irradiation showed little advantage because of the high risk of brain necrosis associated with them.


Inconsistent expression of glycolipid sulfotransferase activity between hepatoma and serum. Glycolipid sulfotransferase activity in human and rat hepatocellular carcinoma tissues was studied, since an elevated level of the enzyme activity in serum had been demonstrated in cancer patients. The level of the enzyme activity in carcinoma tissues, however, could not be distinguished from that of normal controls. Similar observations were made for rat hepatoma. A higher level of enzyme activity was observed in the female than in the male. Inconsistent expression between hepatoma tissue and serum suggests that humoral factor(s) derived from hepatoma tissue stimulates production of the sulfotransferase, which is released into the blood-stream in the host.


Metabolism of 25-hydroxydihydrotachysterol3 in bone cells in vitro. Dihydrotachysterol3, a reduced (or hydrogenated) analog of vitamin D3 in which the A ring has been rotate through 180 degrees , is, after hepatic 25-hydroxylation, converted in vivo to a dihydroxylated metabolite, termed peak H, which is at present unidentified but with good affinity for the vitamin D receptor. Although peak H is made in relatively large amounts in vivo, it has not yet been possible to synthesize it in vitro. Mass spectrometric evidence suggests that peak H is 25-hydroxylated and the presumption that it is a metabolite of 25-hydroxydihydrotachysterol3 was confirmed by the demonstration that radiolabeled peak H was formed in vivo in the rat after injection of 25-hydroxy-[10,19-3H]dihydrotachysterol3, produced from [10,19-3H]dihydrotachysterol3 in a hepatic cell model. The metabolism of 25-hydroxy-[10,19-3H]dihydrotachysterol3 was also studied in a rat osteosarcoma cell UMR-106, a known target cell for vitamin D, using high (11 microM) and low (10 nM) substrate concentrations. Metabolic products were isolated by lipid extraction, purified by high-performance liquid chromatography, and characterized by direct-probe mass spectrometry and gas chromatography/mass spectrometry. The formation of peak H from 25-hydroxydihydrotachysterol3 could not be demonstrated in UMR-106 cells. However, 25-hydroxydihydrotachysterol3 was metabolized to at least seven side-chain modified metabolites, each of which was extensively characterized and tentatively identified. It is concluded that the vitamin D enzyme system present in UMR-106 cells is able to metabolize dihydrotachysterol3 very efficiently to a series of metabolites but is incapable of producing peak H.