Multiple congenital malformations including generalized hypertrichosis with gum hypertrophy in a child exposed to valproic acid in utero

Fetal valproate syndrome results from in utero exposure to valproic acid. It is characterized by a distinctive facial appearence, a cluster of minor and major anomalies, and central nervous system dysfunction. We report on a child exposed prenatally to valproic acid with unusual anomalies. This patient was the first child of young parents. Mother had several generalized seizures one year before this pregnancy, and since than she took valproic acid. Pregnancy was otherwise uneventful. At birth physical examination showed generalized hypertrichosis sparing palms and soles, coarse face, gum hypertrophy, hypotonia, club feet and club hands, two annular constrictions of the right lower leg, and abnormal dermatoglyphics. Skeletal X-rays were normal. Gum hypertrophy and hypertrichosis may be part of a broader pattern of altered morphogenesis in fetus exposed to valproic acid or this patient had two conditions, fetal valproate syndrome and hypertrichosis with gum fibromatosis.

[Retinopathy of prematurity: 10-year retrospective study at the University Hospital of Strasbourg]

OBJECTIVES

This work was splitted in two parts: the first one was the study of retinopathy incidence in premature infants less than 33 weeks gestation, born between 1988 and 1997; the second one is the identification of severe retinopathy different risk factors.

PATIENTS AND METHODS

Our study was retrospective over ten years. All premature infants less than 33 weeks gestation born between January 1, 1988 and December 31 1997, admitted to the Strasbourg neonatal intensive care unit with retinopathy, were included (164 children). First we studied the incidence evolution of retinopathy over these ten years; then by a statistical study (univaried and multivaried) we looked for a significant difference for several factors between the infants with mild retinopathy and the group with severe ocular disease.

RESULTS

Retinopathy incidence decreased in ten years from 13.7 to 6.7% for the moderate forms (P < 0.001) and from 3.7 to 1.7% for severe stage (non significant). A significant difference was found for various factors after comparison between both groups. The birth weight (P = 5 x 10(-4)), the gestational age (P = 4 x 10(-6)), were weaker in the group with severe retinopathy. A maternofetal or nosocomial infection (P = 0.009; P = 0.002), hemodynamic shock (P = 10(-6)), patent ductus arteriosus (P = 10(-6)), bronchopulmonary dysplasia (P = 3 x 10(-6)), postnatal steroid treatment (P = 0.007), respiratory distress syndrome (P = 0.01), were all more frequent in the severe retinopathy sample. The number of days with oxygenotherapy (P = 10(-6)) and mechanical ventilation (P = 10(-6)) the number of blood transfusion (P = 10(-5)) were higher in this group than in the other. The logistic regression analysis showed that the hemodynamic parameters influence mostly on the risk of severe ocular disease, like an hemodynamic shock syndrome (OR = 16.94; CI = 2.12-135.77) or a patent ductus arteriosus (OR = 5.36; CI = 1.53-18.74).

CONCLUSION

A decrease of the retinopathy incidence in premature infants was observed in ten years, probably due to better care in the neonatal period. An unstable hemodynamic state would be one prominent risk factor in the genesis of severe retinopathy of prematurity.

Severe hypernatremic dehydration in an infant with Netherton syndrome

Netherthon syndrome is a rare autosomal recessive disease characterized by ichthyosis, the characteristic hair abnormality trichorrhexis invaginata and atopic manifestations. We report a female child with the severe hypernatremic dehydration form of the Netherton syndrome born as the first child of consanguineous parents. Ichthyosis was present at birth. She was admitted to the intensive care unit at the age of 4 days with important loss of weight and dehydration. Severe hypernatremia and convulsions occurred. Despite intensive care the baby died at the age of 11 days. The diagnosis of Netherton syndrome was confirmed by the finding of the pathognomonic hair shaft anomaly trichorrhexis invaginata (bamboo hair) and premature lamellar body secretion and foci of electron-dense material in the intercellular spaces of stratum corneum as relatively specific markers for Netherton syndrome. Netherton syndrome is characterized by a large variability in phenotypic expression. The major neonatal complication is the hypernatremic dehydration, which can be fatal as in this patient or complicated by neurologic signs (intracranial hemorrhage) and secondary sequellae. Molecular studies revealed a mutation in SPINK 5, encoding a serine protease inhibitor. Prenatal diagnosis was performed in the second pregnancy and showed that the fetus was equally affected.

Pallister-Hall syndrome with stenosis of the cricoid cartilage and microphallus without hypopituitarism

The Pallister-Hall syndrome is characterised by a spectrum of anomalies including congenital hypothalamic "hamartoblastoma" hypopituitarism, imperforate anus, polydactyly and various visceral anomalies. Rare familial cases with an autosomal dominant inheritance pattern with variable expressivity have been reported. Cases of more mildly affected individuals with Pallister-Hall syndrome have been described, including cases of asymptomatic individuals. We report a case of Pallister-Hall syndrome with microphallus and without growth hormone deficiency that has been followed successfully for two years. The patient presented postaxial polydactyly of hands, dysplasic nails, imperforate anus, small penis, scrotum bifidum with very thin urethra, bifid epiglottis and a bilateral simian crease. There was vesico-ureteral-reflux, insertional hexadactyly of the left hand and two Y shaped metacarpal with six fingers at the right hand. Brain MR imaging revealed a large sellar and suprasellar mass. A perineal anorectoplasty and a vesicostomy were performed. Laryngeal dyspnea appeared when he was 13 months old. Bronchoscopy revealed anterior synechia of vocal cords with cricoidian stenosis. A tracheostomy was performed. Mental development was normal. No mutation of the zinc finger transcription factor gene, GLI 3 was detected.

[Pemphigoid gestationis and bullous lesions in the newborn]

BACKGROUND

Pemphigoid gestations is very seldom responsible for cutaneous lesions in newborns through passive transfer of the autoimmune disease from mother to infant.

CASE REPORT

We report an additional case of a newborn presenting with an extensive but transitory bullous eruption despite the absence of circulating autoantibodies.

CONCLUSION

Such examples of transplacental pemphigoid are so uncommon that the pathogenic role of IgG autoantibodies is being questioned.

Influence of the selective ORL1 receptor agonist, Ro64-6198, on rodent neurological function

Identification of synthetic agonists and antagonists at orphan receptors represents an important step for understanding their physiological function and therapeutic potential. Accordingly, we have recently described a non-peptide agonist at the opioid receptor like (ORL1) receptor (1S,3aS)-8-(2,3,3a,4,5,6-hexahydro-1H-phenalen-1-yl)-1-phenyl-1,3,8-triazaspiro[4.5]decan-4-one (Ro64-6198; Jenck et al., PNAS 94 (2000) 4938; Wichmann et al., Eur. J. Med. Chem. 35 (2000) 839). We have investigated the effects of this compound in various tests of rodent neurological function, utilising ORL1 knockout mice to examine the pharmacological specificity of Ro64-6198. In male C57BL/6J mice, effects on balance and motor co-ordination were detected following low doses (0.3-1mg/kg IP) of Ro64-6198. At higher doses (1-3mg/kg IP), effects on swim behaviour and hypothermia was observed. At 10mg/kg, each effect became more profound and a severe neurological disturbance appeared, including loss of righting reflex. These effects of Ro64-6198 (10mg/kg IP) were absent in ORL1 receptor knockout mice. In male, hooded Lister rats, Ro64-6198 (6-10mg/kg IP), produced some disturbance of neurological function, including hypoactivity, rotarod performance, grip strength and mild hypothermia. An impairment of food responding under a variable interval (VI) 20s schedule of reinforcement was noted at 3mg/kg. These results confirm Ro64-6198 to be a highly selective pharmacological tool to investigate ORL1 receptor function in vivo and, furthermore, that activation of this receptor is accompanied by a variety of effects on neurological function.

Reduction of Cr (VI) by cysteine: significance in human lymphocytes and formation of DNA damage in reactions with variable reduction rates

The induction of genotoxicity by Cr (VI) is dependent on its reductive activation inside the cell. Our recent studies have found that reduction of Cr (VI) by cysteine resulted in the formation of mutagenic Cr (III)-DNA adducts in the absence of oxidative DNA damage. In this work, we examined the formation of oxidative and Cr (III)-dependent types of DNA damage under a broader range of Cr (VI) and cysteine concentrations and investigated a potential role of this reducer in intracellular metabolism of Cr (VI). Peripheral lymphocytes from unexposed humans had 7.8-fold excess of glutathione over cysteine, whereas lymphocytes from stainless steel welders contained only 3 times higher amount of glutathione (p = 0.0009) which was entirely caused by the decrease in the concentration of glutathione. A strong correlation (r = 0.72) between the levels of both thiols was found in lymphocytes from controls. The number of DNA-protein crosslinks in lymphocytes from welders was 4.1 times higher than among controls, indicating the presence of Cr (VI)-dependent DNA damage. The average rate of Cr (VI) reduction by cysteine was approximately 5 times faster than that by glutathione. Higher reduction rate combined with the decrease in the intracellular concentration of glutathione should make cysteine a predominant Cr (VI)-reducing thiol in lymphocytes of welders. Analysis of the initial rates of Cr (VI) reduction by different concentrations of cysteine suggested the presence of one- and two-electron pathways, with one-electron mechanism dominating in the physiological range of concentrations. There was no detectable formation of DNA breaks or abasic sites under a broad range of Cr (VI) and cysteine concentrations, resulting in up to 68-fold differences in the rates of reduction and the production of as many as 3 Cr (III)-DNA adducts per 10 bp. The reactions with slow reduction rates (low concentrations of cysteine) led to the most extensive formation of Cr (III)-DNA adducts. In summary, these results further establish Cr (III)-DNA adducts as the major form of DNA damage resulting from Cr (VI) metabolism by cysteine. The role of cysteine in reduction of Cr (VI) becomes more significant under conditions of occupational exposure to Cr (VI)-containing welding fumes.

[Tetralogy of Fallot in monozygotic twins]

The causative mechanisms of congenital heart defects remain unclear and little is known about the respective implication of chance, genetics and environment, though recent findings in molecular biology may provide further insight into understanding the pathophysiologic basis of congenital heart diseases.

CASE REPORT

We report the exceptional but significant case of monozygotic twins both affected by tetralogy of Fallot, for whom prenatal diagnosis ruled out 22q11 microdeletion.

CONCLUSION

We discuss how far this observation is consistent with the latest hypothesis, which emphasizes the leading role of genetic factors. Several genes indeed, either separately or in combination, could be responsible for those defects, even if other influences may still come into play.

Characterization of [(3)H]Quisqualate binding to recombinant rat metabotropic glutamate 1a and 5a receptors and to rat and human brain sections

We have investigated the binding properties of [(3)H]quisqualate to rat metabotropic glutamate (mGlu) 1a and 5a receptors and to rat and human brain sections. Saturation isotherms gave K:(D) values of 27 +/- 4 and 81 +/- 22 nM: for mGlu1a and mGlu5a receptors, respectively. Several compounds inhibited the binding to mGlu1a and mGlu5a receptors concentration-dependently. (S:)-4-Carboxyphenylglycine, (S:)-4-carboxy-3-hydroxyphenylglycine, and (R,S)-1-aminoindan-1,5-dicarboxylic acid, which completely inhibited [(3)H]quisqualate binding to the mGlu5a receptor, were inactive in a functional assay using this receptor. The distribution and abundance of binding sites in rat and human brain sections were studied by quantitative receptor radioautography and image analysis. Using 10 nM: [(3)H]quisqualate, a high density of binding was detected in various brain regions with the following rank order of increasing levels: medulla, thalamus, olfactory bulb, cerebral cortex, spinal cord dorsal horn, olfactory tubercle, dentate gyrus molecular layer, CA1-3 oriens layer of hippocampus, striatum, and cerebellar molecular layer. The ionotropic component of this binding could be inhibited by 30 microM: kainate, revealing the distribution of mGlu1+5 receptors. The latter were almost completely inhibited by the group I agonist (S:)-3,5-dihydroxyphenylglycine. The binding profile correlated well with the cellular sites of synthesis and regional expression of the respective group I receptor proteins revealed by in situ hybridization histochemistry and immunohistochemistry, respectively.

Reductive metabolism of Cr(VI) by cysteine leads to the formation of binary and ternary Cr--DNA adducts in the absence of oxidative DNA damage

Carcinogenic chromium(VI) compounds require reduction for the induction of genotoxicity. In this work, we examined a spectrum of DNA damage produced in Cr(VI)-cysteine reactions at neutral pH. Cr(VI) reduction followed single-component kinetics and led to a significant oxidation of 2',7'-dichlorofluoroscein (DCFH). The presence of residual Fe and/or Cu resulted in an increased level of oxidation of DCFH, and the removal of adventitious metals required rigorous purification of cysteine. DNA breakage and abasic sites were not detected, suggesting that DNA is much less susceptible to oxidation than DCFH. Cr(VI) reduction led to the extensive formation of Cr-DNA adducts and Cys-Cr-DNA and interstrand DNA-DNA cross-links. Cr-DNA binding resulted in unwinding of supercoiled DNA and a greater stability of the DNA duplex to denaturation. Ionically bound Cr comprised 40-60% of the total DNA-bound Cr, while the remaining Cr-DNA complexes represented stable Cr-DNA adducts that exhibited significant resistance to dissociation by EDTA. The yield of Cr-DNA adducts was strongly influenced by the nature of the buffer that was used. Phosphate buffer completely blocked Cr-DNA binding, whereas adduct formation in organic buffers was largely dependent on the extent of buffer ionization. The level of formation of Cr-DNA adducts was several times higher at pH 6 which resulted from lower levels of buffer ionization and diminished competition from hydroxyl ions. Yield of a number of Cr-DNA and Cys-DNA adducts increased linearly as a function of Cr(VI) concentration, whereas formation of interstrand DNA cross-links exhibited exponential dose dependence. Approximately 60-90 min was required to convert a Cr-DNA monoadduct into a DNA-DNA cross-link. Prolonged incubations at alkaline conditions led to a selective cleavage of cross-linked DNA. The alkali sensitivity of Cr-adducted DNA suggests that results of alkaline elution analysis of DNA damage in cells require a more cautious interpretation. Overall, a spectrum of DNA damage derived from Cr(VI)-cysteine reactions was similar to that found in exposed cells.

[Phrenic nerve paralysis of obstetrical origin: favorable course using continuous positive airway pressure]

INTRODUCTION

Isolated diaphragmatic paralysis due to obstetrical factors is rare and therapeutic management modalities are not quite clear.

CASE REPORT

A neonate born by breech delivery presented with respiratory distress due to isolated paralysis of the right hemidiaphragm. The clinical course was progressive, his condition worsening with oxygen supplementation. Continuous positive airway pressure (CPAP) delivered via a nasal cannula was started in the one-month-old child, inducing gradual improvement towards recovery at the age of two months and a half.

CONCLUSION

Non-invasive nasal CPAP should be proposed for the treatment of phrenic nerve obstetrical palsy before introducing more invasive ventilation techniques. Surgical plication should be delayed until the child reaches the age of at least three months.

[Buprenorphine and pregnancy. Analysis of 24 cases]

BACKGROUND

Maintenance therapy of drug-addict mothers with medical and psychosocial support may reduce complications (prematurity, growth retardation, fetal distress and fetal death). Methadone has been widely used during pregnancy with beneficial effects. Buprenorphine (BUP) is used more and more and shows the same beneficial effects.

PATIENTS AND METHOD

Twenty-four pregnant women received BUP and their infants were enrolled in the study. Thirteen retrospective (GI) and 11 prospective (GII) cases were studied. In the GII, the women were treated and followed up in an interdisciplinary manner.

RESULTS

Complications in GII were less frequent than in GI: 9 vs 30% of prematurity, 9 vs 46% of fetal growth retardation and 0 vs 23% of acute fetal distress. However, the frequency of withdrawal syndrome was the same in both groups, 63 vs 69%, though improvements came more rapidly in GII.

CONCLUSION

This study shows that the use of BUP during pregnancy, combined with medical and psychosocial support, may reduce addiction complications. This support has to be maintained after the birth.

Characterization of (2S,2'R,3'R)-2-(2',3'-[3H]-dicarboxycyclopropyl)glycine binding in rat brain

[(2S,2'R,3'R)-2-(2',3'-[3H]Dicarboxycyclopropyl)glycine ([3H]DCG IV) binding was characterized in vitro in rat brain cortex homogenates and rat brain sections. In cortex homogenates, the binding was saturable and the saturation isotherm indicated the presence of a single binding site with a K(D) value of 180 +/- 33 nM and a Bmax of 780 +/- 70 fmol/mg of protein. The nonspecific binding, measured using 100 microM LY354740, was <30%. NMDA, AMPA, kainate, L(-)-threo-3-hydroxyaspartic acid, and (S)-3,5-dihydroxyphenylglycine were all inactive in [3H]DCG IV binding up to 1 mM. However, several compounds inhibited [3H]DCG IV binding in a concentration-dependent manner with the following rank order of potency: LY341495 = LY354740 > DCG IV = (2S,1'S,2'S)-2-(2-carboxycyclopropyl)glycine > (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid > (2S,1'S,2'S)-2-methyl-2-(2-carboxycyclopropyl)glycine > L-glutamate = ibotenate > quisqualate > (RS)-alpha-methyl-4-phosphonophenylglycine = L(+)-2-amino-3-phosphonopropionic acid > (S)-alpha-methyl-4-carboxyphenylglycine > (2S)-alpha-ethylglutamic acid > L(+)-2-amino-4-phosphonobutyric acid. N-Acetyl-L-aspartyl-L-glutamic acid inhibited the binding in a biphasic manner with an IC50 of 0.2 microM for the high-affinity component. The binding was also affected by GTPgammaS, reducing agents, and CdCl2. In parasagittal sections of rat brain, a high density of specific binding was observed in the accessory olfactory bulb, cortical regions (layers 1, 3, and 4 > 2, 5, and 6), caudate putamen, molecular layers of the hippocampus and dentate gyrus, subiculum, presubiculum, retrosplenial cortex, anteroventral thalamic nuclei, and cerebellar granular layer, reflecting its preferential (perhaps not exclusive) affinity for pre- and postsynaptic metabotropic glutamate mGlu2 receptors. Thus, the pharmacology, tissue distribution, and sensitivity to GTPgammaS show that [3H]DCG IV binding is probably to group II metabotropic glutamate receptors in rat brain.

Impaired glycolysis and protein catabolism induced by acid in L6 rat muscle cells

BACKGROUND

In skeletal muscle, metabolic acidosis stimulates protein degradation and oxidation of branched-chain amino acids. This could occur to compensate for impairment of glucose utilization induced by acid.

METHODS

To test this hypothesis, glycolysis and protein degradation (release of [14C]-phenylalanine) were measured in L6 skeletal muscle cells cultured in Eagle's minimum essential medium at pH 7.1 or 7.5 for up to 3 days.

RESULTS

No marked changes in total DNA or in cell viability were detected, nor was there any significant effect on intracellular pH or the water content of the cells (which is thought to be a key regulator of protein turnover, especially in liver). In spite of this, acid stimulated protein degradation, induced net protein loss from the cultures, inhibited glucose uptake and glycolysis (lactate output) and was associated with increased [1-14C]-leucine oxidation. Effects on protein degradation and glycolysis were gradual, reaching a maximum after 20-30 h. To investigate whether glycolytic flux itself can influence protein degradation, increased glycolysis was simulated by adding glucose (20 mmol L-1) or pyruvate (1 mmol L-1) to the medium. At pH 7.1, neither addition had any effect on protein degradation.

CONCLUSION

Although acid-induced protein wasting is associated with impaired glycolysis, no obligatory coupling exists between glycolytic flux and protein degradation.

Binding characteristics of a potent AMPA receptor antagonist [3H]Ro 48-8587 in rat brain

A new AMPA receptor antagonist, Ro 48-8587, was characterized pharmacologically in vitro. It is highly potent and selective for AMPA receptors as shown by its effects on [3H]AMPA, [3H] kainate, and [3H] MK-801 binding to rat brain membranes and on AMPA- or NMDA-induced depolarization in rat cortical wedges. [3H]Ro 48-8587 bound with a high affinity (KD = 3 nM) to a single population of binding sites with a Bmax of 1 pmol/mg of protein in rat whole brain membranes. [3H]Ro 48-8587 binding to rat whole brain membranes was inhibited by several compounds with the following rank order of potency: Ro 48-8587 > 6-nitro-7-sulphamoylbenzo[f] quinoxaline-2,3-dione (NBQX) > YM 90K > 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) > quisqualate > AMPA > glutamate > kainate > NMDA. The distribution and abundance of specific binding sites (approximately 95% of total) in sections of rat CNS, revealed by quantitative receptor radioautography and image analysis, indicated a very discrete localization. Highest binding values were observed in cortical layers (binding in layers 1 and 2 > binding in layers 3-6), hippocampal formation, striatum, dorsal septum, reticular thalamic nucleus, cerebellar molecular layer, and spinal cord dorsal horn. At 1 nM, the values for specific binding were highest in the cortical layers 1 and 2 and lowest in the brainstem (approximately 2.6 and 0.4 pmol/mg of protein, respectively). Ro 48-8587 is a potent and selective AMPA receptor antagonist with improved binding characteristics (higher affinity, selectivity, and specific binding) compared with those previously reported.

High-versus low-dose erythropoietin in extremely low birth weight infants. The European Multicenter rhEPO Study Group

OBJECTIVE

To investigate whether a weekly 1500 IU/kg dose of recombinant human erythropoietin (rhEPO) is more effective than a dose of 750 IU/kg/week in preventing anemia and reducing the transfusion need in infants with birth weights less than 1000 gm.

STUDY DESIGN

In a randomized, double-blind, multicenter trial, 184 infants with birth weights between 500 and 999 gm were treated with either rhEPO 750 (low-dose group) or 1500 IU/kg/week (high-dose group) from day 3 of life until 37 weeks' corrected age.

RESULTS

Thirty-two percent of the infants in each group did not receive any transfusion during the treatment period. The total volume of erythrocytes received was similar in each group. The success rate, defined as no transfusion needed and hematocrit value 0.30 L/L or greater, was 27.6% in the low-dose and 29.5% in the high-dose group (p = 0.96).

CONCLUSION

Doubling the rhEPO dose of 750 IU/kg/week is not indicated in infants with birth weights less than 1000 gm.

In vitro binding properties in rat brain of [3H]Ro 25-6981, a potent and selective antagonist of NMDA receptors containing NR2B subunits

The in vitro binding of a new subtype-selective NMDA receptor antagonist, [3H]Ro 25-6981, to rat brain membranes and sections was characterized. The compound bound to a single site on the membranes with a K(D) of 3 nM and a Bmax of 1.6 pmol/mg of protein. Specific binding, defined with a new NR2B-specific antagonist, Ro 04-5595 [1-(4-chlorophenyl)-2-methyl-6-methoxy-7-hydroxy-1,2,3,4-tetrahydroisoqu inoline], at 10 microM, was fully inhibited by several compounds with the following rank order of affinities--Ro 25-6981 > CP-101,606 > Ro 04-5595 = ifenprodil >> eliprodil > haloperidol > spermine > spermidine > MgCl2 > CaCl2--and partially inhibited by competitive glutamate recognition site antagonists. A high density of binding sites was detected, radioautographically, in several layers of the cerebral cortex, in the hippocampus, dentate gyrus, tuberculum olfactorium, caudate putamen, medium densities in the globus pallidus, thalamus, spinal cord dorsal horn, and motoneurons, whereas the cerebellum, pons, and medulla were, with a few exceptions, e.g., locus coeruleus, poorly labeled. Overall, the distribution of [3H]Ro 25-6981 binding sites correlated well with that of NR2B (but not NR2A) transcripts, revealed by in situ hybridization histochemistry. The high affinity of [3H]Ro 25-6981 for NR2B-containing receptors renders this compound the ligand of choice to study the regulation of NR2B-containing receptor expression.

In vitro binding characteristics of a new selective group II metabotropic glutamate receptor radioligand, [3H]LY354740, in rat brain

The in vitro binding of [3H]LY354740, the first high affinity group II-selective metabotropic glutamate (mGlu) receptor radioligand, was characterized in rat cortical, hippocampal, and thalamic membranes as well as in rat brain sections. [3H]LY354740 binding was saturable in all regions investigated. Nonspecific binding (in the presence of 10 microM DCG-IV) was approximately 8% of the total. Ionotropic glutamate receptor agonists, N-methyl-D-aspartate, (R,S)-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid/kainate, a Na+-dependent glutamate uptake blocker as well as a group I-selective mGlu receptor agonist (all up to 1 mM) did not inhibit [3H]LY354740 binding to cortical membranes. However, several known metabotropic receptor ligands inhibited the binding with the following rank order of potency: LY354740 = LY341495 > (2S,2'R, 3'R)-2-(2',3'-dicarboxycyclopropyl)glycine = (2S,1'S, 2'S)-2-(2-carboxycyclopropyl)glycine > glutamate = (1S, 3R)-1-aminocyclopentane-1,3-dicarboxylic acid > (2S,1'S, 2'S)-2-methyl-2-(2-carboxycyclopropyl)-glycine > quisqualate > ibotenate > L-2-amino-3-phosphonopropionic acid = (S)-alpha-methyl-4-carboxyphenylglycine > L-(+)-2-amino-4-phosphonobutyric acid. N-Acetyl-aspartyl-glutamate, (2S)-alpha-ethylglutamic acid, and (R, S)-alpha-methyl-4-phosphonophenylglycine inhibited [3H]LY354740 binding in a biphasic manner. Guanosine-5'-O-(3-thiotriphosphate concentration-dependently and almost completely inhibited the binding. Finally, in parasagittal sections of rat brain, a high density of specific binding was observed in the accessory olfactory bulb, cortical regions (layers 1-3 > 4-6), caudate putamen, molecular layers of the hippocampus and dentate gyrus, presubiculum, retrosplenial cortex, anteroventral thalamic nuclei, and cerebellar granular layer, reflecting its preferential (perhaps not exclusive) affinity for presynaptic and postsynaptic mGlu2 receptors. Thus, the pharmacology, tissue distribution, and sensitivity to guanosine-5'-O-(3-thiotriphosphate show that [3H]LY354740 binding probably occurs to group II mGlu receptors in rat brain.

Antenatal diagnosis of brain damage in the survivor after the second trimester death of a monochorionic monoamniotic co-twin: case report and literature review

At 28 weeks of amenorrhea, 1 fetus of a monoamniotic twin pregnancy died. Ultrasound and Doppler investigations of the surviving twin were normal. Three weeks later, endovaginal ultrasound and magnetic resonance imaging revealed massive bilateral cerebral ischemic necrosis in the surviving twin. In utero fetal blood sampling carried out before the termination did not reveal either anemia or thrombopenia. Current data suggest that cerebral or renal ischemic complications could set in immediately after the death of the first twin as a result of a period of acute hypotension. At least 2 weeks are necessary for them to be identifiable by ultrasound. It seems that they cannot be prevented by prompt delivery of the second twin.