Cerebrospinal fluid synaptic proteins as useful biomarkers in tyrosine hydroxylase deficiency.

Tyrosine hydroxylase (TH) deficiency is an inborn error of dopamine biosynthesis and a cause of early parkinsonism. Two clinical phenotypes have been described. Type "B": early onset severe encephalopathy; type "A": later onset, less severe and better response to L-dopa. We aimed to study the expression of several key dopaminergic and gabaergic synaptic proteins in the cerebrospinal fluid (CSF) of a series of patients with TH deficiency and their possible relation with the clinical phenotype and response to L-DOPA. Dopamine transporter (DAT), D2-receptor and vesicular monoamine transporter (VMAT2) were measured in the CSF of 10 subjects with TH deficiency by Western blot analysis. In 3 patients, data of pre- and post-treatment with L-DOPA were available, and in one of them, GABA vesicular transporter was determined. Results were compared to an age-matched control population. The concentration of D2-receptors in CSF was significantly higher in patients with TH deficiency than in controls. Similarly, DAT and vesicular monoamine transporter type 2 were up-regulated. Studies performed before L-DOPA, and on L-DOPA therapy showed a paradoxical response with D2 receptor expression increase as L-Dopa doses and homovanillic concentration gradually raised in a B phenotype patient. The opposite results were found in two patients with A phenotype. However, this is a very small sample, and further studies are needed to conclude robust differences between phenotypes. Synaptic proteins are detectable in the CSF and their quantification can be useful for understanding the pathophysiology of neurotransmitter defects and potentially to adjust and personalize treatments in the future.

Treatment for dystonia in childhood.

Management of childhood dystonia differs in certain respects from that of adult dystonia: (i) childhood dystonia is more often secondary than primary; (ii) mixed motor disorders are frequent; (iii) in children, the course of dystonia may be influenced by ongoing brain maturation and by the remarkable plasticity of the young brain; (iv) drug tolerability and effectiveness can be different in children; (v) the therapeutic strategy must be discussed with both the patient and his or her parents; and (vi) the child's education must be taken into account. Based on a systematic review of the literature through June 2011 and on our personal experience, we propose a therapeutic approach to childhood dystonia. After a detailed clinical evaluation and a comprehensive work-up to rule out a treatable cause of dystonia, symptomatic treatment may include various drugs, local botulinum toxin injections, and deep brain stimulation, in addition to rehabilitation.

Dystonia. The paediatric perspective.

BACKGROUND AND AIMS: This review focuses on some paediatric dystonias such as transient dystonias, new primary paediatric-onset dystonias, dopamine biosynthesis defects and new paroxysmal disorders. It is designed to provide practical help for neurologists and neuropediatricians to make appropriate diagnoses and plan the management of these disorders. MATERIAL AND METHODS: Literature searches were performed and original papers, meta-analyses and review papers were reviewed. CONCLUSION: Paediatric onset dystonia is an increasingly interesting group of conditions that provides an expanding area of neuroscientific knowledge. Given the long life expectancy of children, appropriate treatment at the correct moment will have an important, lasting effect on the personal, social and healthcare domains.

Inborn errors of metabolism and motor disturbances in children.

Motor disturbances are very common in paediatric neurology. Often families can be reassured that these are just variants of normal development. However, abnormal movements can also be the hallmark of severe brain dysfunction of different and complex origins. This review concentrates on motor disturbances as frequent and important symptoms of inborn errors of metabolism. A structured diagnostic approach is developed taking into account age-dependent physiological developments and pathophysiological responses of gross and fine motor functions. A series of investigations are presented with the primary aim of early diagnosis of treatable conditions. The correct recognition and differentiation of movement disorders (ataxia, rigid akinetic syndrome (Fparkinsonism_), dystonia, athetosis, tremor,and others), spasticity, and neuromuscular disorders, requires profound neurological expertise. A high level of suspicion and close interaction between paediatric neurologists and specialists in inborn errors of metabolism are indispensable to effectively and timely identify patients in whom motor disturbances are the presenting and/or main symptom of an inborn error.

[Pharmacological preconditioning with sildenafil of warm ischemic kidneys]. / Precondicionamiento farmacológico con sildenafilo del riñón con isquemia normotérmica.

OBJECTIVES: To evaluate the preconditioning effect of sildenafil administered preoperatively in kidneys subjected to a period of warm ischemia (WI), hypothermic perfusion (HP) or cold storage (CS) and finally, autotransplant (AT). MATERIAL AND METHOD: We studied 6 groups of autotransplanted kidneys: no-WI-inmediate AT (Group A); 45 min of WI + immediate AT (Group B); 45 min of WI + 60 min of HP + autotransplant (Group C); 45 min of WI + 60 min of CS + autotransplant (Group D); 100 mg of oral sildenafil preoperatively + 45 min of WI + autotransplant (Group E); 100 mg of oral sildenafil preoperatively + 45 min of WI+60 min of HP + autotransplant (Group F). Belzer solution was used for HP; UW-Viaspan for CS. Inmediately after the autotransplant (reperfusion period), we recorded in real time for 60 min the values of Renal vascular Flow (RVF) and Renal Vascular Resistance (RVR). Nitric Oxide levels in the cava and renal graft vein were recorded every 15 min during the 60 min of the reperfusion-study period. Conventional & Electronic microscopy were completed after the process. RESULTS: We obtained significant higher values of RVF and lower values of RVR in sildenafil groups (E and F) in comparison to the other groups (A-D) (Table 1). NO levels were also significantly higher in groups E and F (Fig. 1). Groups A, B, E and F showed integrity of tubule and endothelium in comparison to groups C and D in the microscopic study. CONCLUSIONS: We showed a beneficious effect of sildenafil in inmediate post-transplant reperfusion hemodynamic and biochemical parameters of kidneys subjected to a critical period of warm-ischemia.

[Movement disorders]. / Trastornos del movimiento.

Thanks to the application of modern techniques such as next-generation sequencing in the study of apparently non-inherited encephalopathies it has become possible to describe de novo pathogenic mutations in unsuspected genes and to define the phenotypes of these mutations. Interestingly, in most cases, their clinical signs and symptoms show a spectrum in which epileptic encephalopathy, neurodevelopmental disorder and hyperkinetic abnormal movement disorders overlap. Their pathophysiology is located in synapses (synaptopathies). This article offers a brief summary of these disorders and also includes a simple note, in honour of Dr Natalio Fejerman (1934-2018), on the so-called «benign polymorphic disorder of infancy¼.

TITLE: Trastornos del movimiento.Gracias a la aplicacion de modernas tecnicas como la siguiente secuenciacion (next-generation sequencing) en el estudio de encefalopatias aparentemente no heredadas ha sido posible descubrir mutaciones patogenas de novo en genes insospechados y definir los fenotipos de estas mutaciones. Es interesante que, en la mayoria de los casos, sus cuadros clinicos muestran un espectro en el que se solapan encefalopatia epileptica, trastorno del neurodesarrollo y movimientos anormales de tipo hipercinetico. Su fisiopatologia se localiza en la sinapsis (sinaptopatias). En este articulo se hace una breve sintesis de estos trastornos y se añade una sencilla nota, en honor al Dr. Natalio Fejerman (1934-2018), sobre la base del denominado «trastorno polimorfo benigno del lactante¼.

[Inborn errors of neurotransmitters in neuropaediatrics]. / Errores congénitos de los neurotransmisores en Neuropediatría.

AIMS: The aim of this work is to describe the clinical, biochemical and genetic characteristics of neurotransmitter diseases at the paediatric age, together with possible forms of treatment. We also sought to determine the diagnostic methodology of these disorders (collection and analysis of samples). DEVELOPMENT: These diseases essentially consist of a deficit of biogenic amines and alterations in GABA metabolism (gamma-aminobutyric acid). Disorders affecting the neurotransmission of biogenic amines often present in the form of hypokinesia, trunk hypotonia with increased limb tone, oculogyric crises, ptosis, faulty temperature regulation or abnormal movements. Defects in GABA metabolism give rise to epileptic encephalopathies and unspecific mental retardation, sometimes associated to signs of cerebellar dysfunction, convulsions and alterations in neuroimaging studies. Overall incidence of these diseases is low but they are unquestionably under-diagnosed, since they cannot be detected by conventional studies in plasma and urine, and require extraction and directed analysis of cerebrospinal fluid (CSF) for their detection. Additionally, the CSF study must be carried out in specific standardised conditions. Segawa's disease, or dopa-responsive dystonia, responds extremely well to therapy, whereas the other entities respond in varying ways to the different therapeutic alternatives. CONCLUSIONS: It is important for the paediatrician to know about these entities as a group of treatable neurometabolic diseases. Moreover, their detection would allow prenatal diagnosis in the vast majority of cases.

Autosomal dominant Emery-Dreifuss muscular dystrophy: a new family with late diagnosis.

Emery-Dreifuss muscular dystrophy is characterized by the clinical triad of early onset contractures of elbows, Achilles tendons and spine, wasting and weakness with a predominantly humero-peroneal distribution and life-threatening cardiac conduction defects and/or cardiomyopathy. Two main types of inheritance have been described: the X-linked form is caused by mutations in the STA gene on locus Xq28 and the gene for the autosomal dominant form (LMNA gene) has been localized on chromosome 1q11-q23. Recently, mutations in this LMNA gene have been also found to be responsible for the less frequent autosomal recessive form of the disease. Although all forms share a similar clinical presentation, some differences appear to exist between them as has been described recently in a large number of patients. We present the first documented Spanish family genetically confirmed to have autosomal dominant Emery-Dreifuss muscular dystrophy. Clinical, pathological and genetic data are described. We emphasize the difficulties in diagnosis, especially in sporadic cases or young patients in whom the clinical picture is not completely established.

Selective thromboxane synthetase inhibitors and antihypertensive agents. New derivatives of 4-hydrazino-5H-pyridazino[4,5-b]indole, 4-hydrazinopyridazino[4,5-a]indole, and related compounds.

A series of new derivatives of 4-hydrazino-5H-pyridazino[4,5-b]indole (5) and 4-hydrazinopyridazino[4,5-a]indole (12) have been synthesized to investigate their activities as selective thromboxane synthetase inhibitors as well as antihypertensive agents. Several of the prepared compounds were found to be selective thromboxane synthetase inhibitors, in concordance with the Gorman model. The most potent were 8-(benzyloxy)-3,4-dihydro-4-oxo-5H-pyridazino[4,5-b]indole (3c) and 8-methoxy-4-hydrazino-5H-pyridazino[4,5-b]indole (5). This last compound did not inhibit prostacyclin formation and showed an antihypertensive activity similar to that of hydralazine. The acute toxicity in mice for 5a . HCl is about 2.2 times less than that for hydralazine.

Dihydroxynitrobenzaldehydes and hydroxymethoxynitrobenzaldehydes: synthesis and biological activity as catechol-O-methyltransferase inhibitors.

A series of nitro derivatives of dihydroxy- and hydroxymethoxybenzaldehyde was synthesized and tested as potential inhibitors of partially purified pig liver catechol-O-methyltransferase (COMT). All the dihydroxynitrobenzaldehydes prepared were potent inhibitors of COMT, but only one hydroxymethoxynitrobenzaldehyde (3-hydroxy-4-methoxy-5-nitrobenzaldehyde) showed activity as a COMT inhibitor. Although previously reported data showed that the presence of electron-withdrawing substituents at position 5 seemed to be very important for activity as COMT inhibitor, our results suggest that the requirement necessary to enhance the activity of the dihydroxyni-trobenzaldehyde derivatives toward COMT is the presence of the nitro group in a position ortho with respect to one hydroxyl group. The assayed compounds showed a reversible inhibition of COMT, which was mixed for all the dihydroxynitro derivatives but noncompetitive for 3-hydroxy-4-methoxy-5-nitrobenzaldehyde when pyrocatechol was the variable substrate and uncompetitive in all the inhibitors with respect to S-adenosyl-L-methionine.

New 5H-pyridazino[4,5-b]indole derivatives. Synthesis and studies as inhibitors of blood platelet aggregation and inotropics.

Some fused 5H-pyridazino[4,5-b]indoles (7-10), substituted in positions 1 and 4 by hydrazine and/or amino groups, have been synthesized. These new compounds present a planar topography, a dipole with an adjacent acidic proton, and a basic hydrogen-acceptor site opposite the dipole. These compounds have some resemblance to carbazeram and other pyridazino agents with cardiotonic activity. Some of the new compounds here described possess inotropic activity (Table I and II), with a complementary effect as inhibitors of platelet aggregation (Table III and IV). 1-Hydrazino-4-(3,5-dimethyl)-1-pyrazolyl-5H-pyridazino[4,5-b ]indole hydrochloride (7a.HCl) is the first compound described in the literature with activities as inhibitor of PDE-IV and as selective inhibitor of TXA2 synthetase (Table V).

Relevance of benzyloxy group in 2-indolyl methylamines in the selective MAO-B inhibition.

1. Previous studies with indolyl derivatives as monoamine oxidase (MAO) inhibitors have shown the relevance of the indole structure for recognition by the active site of this enzyme. We now report a new series of molecules with structural features which determine the selectivity of MAO inhibition. 2. A benzyloxy group attached at position 5 of the indole ring is critical for this selective behaviour. Amongst all of these benzyloxy-indolyl methylamines, N-(2-propynyl)-2-(5-benzyloxyindol)methylamine FA-73 was the most potent MAO-B 'suicide' inhibitor studied. 3. The Ki values for MAO-A and MAO-B were 800+/-60 and 0.75+/-0.15 nM, respectively. These data represent a selectivity value of 1066 for MAO-B, being 48 times more selective than L-deprenyl (Ki values of 376+/-0.032 and 16.8+/-0.1 nM for MAO A and MAO-B, respectively). The IC50 values for dopamine uptake in striatal synaptosomal fractions from rats were 150+/-8 microM for FA-73 and 68 +/- 10 microM for L-deprenyl whereas in human caudate tissue the IC50 values were 0.36+/-0.015 microM for FA-73 and 0.10+/-0.007 microM for L-deprenyl. Moreover, mouse brain MAO-B activity was 90% ex vivo inhibited by both compounds 1 h after 4 mg kg(-1) administration, MAO-A activity was not affected. 4. These novel molecules should provide a better understanding of the active site of monoamine oxidase and could be the starting point for the design of further selective, non-amphetamine-like MAO-B inhibitors with therapeutic potential for the treatment of neurological disorders.

The kinetics of monoamine oxidase inhibition by three 2-indolylmethylamine derivatives.

The inhibition of bovine brain mitochondrial MAO-A and MAO-B by three acetylenic and non-acetylenic derivatives of 2-indolylmethylamine, chosen among more than 100 new compounds, were studied. The non-acetylenic derivative N-methyl-2(5-hydroxy-1-methylindolyl)methylamine (1) was a weak non-selective inhibitor which was shown to act in a reversible and competitive manner towards the deamination of tyramine. The two acetylenic derivatives N-methyl-N-(2-propynyl)-2-(5-benzyloxy-1-methylindolyl)methylamine (2) and N-methyl-N-(2-propynyl)-2-(5-hydroxy-1-methylindolyl)methylamine (3) were potent MAO inhibitors, one of them non-selective (compound 2) and the other MAO-A selective inhibitor (compound 3). Both of them were irreversible and competitive inhibitors, compound 2 towards the deamination of tyramine and compound 3 towards the deamination of serotonin and beta-phenylethylamine. A mechanism for the inhibition of the enzyme by both irreversible inhibitors is proposed and the inhibition parameters are determined.

Inhibition of catechol-O-methyltransferase by 1-vinyl derivatives of nitrocatechols and nitroguaiacols. Kinetics of the irreversible inhibition by 3-(3-hydroxy-4-methoxy-5-nitro benzylidene)-2,4-pentanedione.

It is well known that activated alkene derivatives react with thiol groups according to a Michael's addition reaction. On the basis of the presence of at least one thiol group essential for the activity of catechol-O-methyltransferase (COMT), several 1-vinyl derivatives of nitrocatechol and nitroguaiacol were synthesized and tested as potential irreversible active site-directed inhibitors of COMT. All the synthesized products were potent inhibitors of partially purified pig liver COMT. However, the inhibition was reversible in most cases, with the exception of 3-(3-hydroxy-4-methoxy-5-nitrobenzylidene)-2,4-pentanedione (compound 2) which inhibited COMT in an irreversible manner. When the inhibition of COMT was measured as a function of the length of time of pre-incubation with 2, biphasic kinetics were observed, suggesting the modification of at least two thiol groups which are essential for COMT activity. The analysis of the two parts of the inhibition curve as a function of the inhibitor concentration showed that compound 2 modified the more reactive group in a non-specific manner, while it behaved as an active site-directed inhibitor on the second slow-reacting thiol group. Importantly, a saturating concentration of S-adenosyl-L-methionine (AdoMet) in the pre-incubation mixture gave pseudo-first order kinetics, suggesting total protection of one thiol group. Magnesium ions had no effect on the protection of COMT by AdoMet. In the presence of 3,5-dinitrocatechol (DNC) slight protection of COMT was observed; when the inactivation of both groups was analysed independently, protection of the specifically modified group was detected, while the reaction with the other group was faster in the presence of DNC. When both AdoMet and DNC were present, inactivation of COMT by 2 was not observed, suggesting that both reacting groups are located at or near the active site.

The effect of side chain substitution at positions 2 and 3 of the heterocyclic ring of N-acetylenic analogues of tryptamine as monoamine oxidase inhibitors.

N-Acetylenic analogues of tryptamine in which the side chain is located at position 2 of the indole ring are compared with those in which the side chain is located at position 3, in terms of their actions as inhibitors of monoamine oxidases A and B. IC50 values at 0 and 30 min of pre-incubation were determined. Time-dependence and irreversible inhibition confirmed that all of them behave as mechanism-based inhibitors. The kinetic constants of each inhibition step were determined for both monoamine oxidase forms and compared between them. In all cases the first-order rate constants for the covalent adduct formation were similar to inhibitor selectivity which is derived solely from differences in affinities for non-covalent binding to the A and B enzymes. Those compounds where the acetylenic side chain was substituted at position 2 of the heterocyclic ring and selective inhibitors of monoamine oxidase A were more potent than those with the side chain in position 3.

Transient movement disorders in children.

Transient movement disorders are quite common in pediatrc practice, occurring mainly in infants. They are underdiagnosed but represent about 20% of cases of movement disorders (tics excluded) seen in a neuropaediatric department. Dystonia, tremor and myoclonus are the most common. Transient idiopathic dystonia of infancy is quite common, and the diagnosis can be suspected on clinical examination. Knowledge of these disorders avoids not only unnecessary tests and treatment, but also familial anxiety.

[Lissencephaly: agyria. A study using the Golgi technic]. / Lisencefalia: agiria. Un estudio con el metodo de Golgi.

A case of lissencephaly (agyria) is reported in which the Golgi stain was used to study the fronto-parietal cortex. The external cellular layer, the so-called true cortex, was shown to be made up of neurons from the 5th and 6th layers of the normal cortex. The neurons in the much less cellular layer were shown to be large pyramidal cells with well-developed dendritic branching and spines. The deeper cellular layer was a neuronal pool without well-defined layering. All the neural forms from the normal cortex were represented. In this layer the inner neurons showed a less advanced stage of development than did those in the outer groups. In the external cellular layer there was a disorganization of neuronal disposition as well. Otherwise typical large and medium-sized pyramidal cells from the outer third showed apical dendrites directed towards deeper structures, and the basal dendrites ran through the marginal layer. Neurons with doulbe dendritic branching and fusiform neurons were present in an abnormal rotated position. In both cases, the axons always showed a descending direction. These findings add to existing knowledge concerning the anatomy of the lissencephalic cortex, although the exact interpretation of the abnormalities found in the external cellular layer remains speculative.

Kinetic behaviour of some acetylenic indolalkylamine derivatives and their corresponding parent amines.

Different methoxy indolalkylamines based on a common structure, and differing in the side chain attached at the 2 position of the indole ring were studied as MAO A inhibitors. Some are acetylenic derivatives and consequently might behave as "suicide" MAO inhibitors (FA 42, FA 43, FA 45). The rest of compounds are the corresponding parent amines and they might behave as MAO substrates (FA 51, FA 52, FA 53, FA 54). The kinetic behaviour of the parent amines as MAO A and MAO B inhibitors and substrates was determined. In case of acetylenic derivatives, kinetic constants defining the non-covalent adduct formation and the covalent adduct formation were also calculated for the mechanism-based inhibition. These parameters will allow us to establish the correlation with structural features that predetermine one compound to be a good MAO substrate or a good MAO A and MAO B inhibitor.

Acetylenic and allenic derivatives of 2-(5-methoxy-1-methylindolyl)alkylamines as selective inhibitors of MAO-A and MAO-B.

A new series of thirty derivatives of 2-(5-methoxy-1-methylindolyl)alkylamines has been synthesized and the compounds assayed as inhibitors of MAO-A and MAO-B from bovine brain mitochondria. IC50 values for both isoenzymes were determined using tyramine as a common substrate. Structure-activity and selectivity relationships are discussed.

Inhibition of MAO by substituted tryptamine analogues.

Three different acetylenic analogues of tryptamine, in which the side chain is attached at the 2 position of the heterocyclic ring, were studied as inhibitors of MAO-A and MAO-B. IC50 values were determined after 30 min preincubation of the enzyme and inhibitor, at 37 degrees C before assay. Irreversibility and time-dependence of the inhibition were also established in each case. The kinetic parameters defining non-covalent complex formation and covalent adduct formation were calculated for the mechanism-based inhibition of both MAO-A and MAO-B by these compounds.