Multiple cardiac rhabdomyomas in tuberous sclerosis complex: case report and review of the literature

Cardiac rhabdomyoma is a benign tumor which constitutes the most common cardiovascular feature of the tuberous sclerosis complex, a multisystem genetically determined neurocutaneous disorder. Cardiac rhabdomyomas can be detected in the prenatal ultrasound, are usually asymptomatic and spontaneously regress within the first three years of life. Less often, the tumors' size, number, and location can produce a mass effect that may lead to blood flow abnormalities or organ dysfunction (heart failure and arrhythmia). In this setting, severe morbidity, and eventually, a lethal outcome despite clinical and surgical treatment may ensue. We describe a fatal case of multiple cardiac rhabdomyomas in a newborn girl. One of the rhabdomyomas was large and unfavorably located, causing significant obstruction of the left ventricular outflow tract. The autopsy identified, in addition to cardiac rhabdomyomas, brain glioneuronal hamartomas (cortical tubers), subependymal nodules and subependymal giant cell tumors, characteristic of the tuberous sclerosis complex. The newborn's family was investigated for the presence of typical clinical symptoms of the complex and image findings showed significant phenotypical variations and a broad symptom spectrum among the family members. This interesting case underscores the variability of tuberous sclerosis complex and the importance of performing a comprehensive postmortem examination in the identification of the cause of death, especially in the setting of familial disease.

MON-424 Suprasellar Immature Cystic Teratoma: A Case Report

Background: Intracranial teratomas are rare and comprise about 0.5% of all intracranial tumors. Actually, a total of 15 cases of sellar-suprasellar teratoma have been described in the last 26 years. Teratomas occur more frequently in children and young adults than in the older population and in males as compared to females. Symptoms at diagnosis are usually neurological defects, diabetes insipidus, and hypopituitarism. Teratoma diagnosis can be suggested through neuroimaging findings. Magnetic Resonance Imaging (MRI) remains the preferred modality. Neuro-radiological findings of mixed-density mass, usually with mixed cystic and solid components inclusions of teeth, fat, and calcification can be suggestive. Tumor markers as beta-HCG and alpha-FP can be useful. Optimal treatment for mature teratoma is neurosurgical excision and in cases of immature teratomas or mixed germ cells tumors teratomas, a multi-step treatment is required with neurosurgical excision, adjuvant or neo-adjuvant radiotherapy and chemotherapy. Clinical Case: A 15-year-old woman, with a headache, secondary amenorrhea, syncope, progressive visual loss, polydipsia, and polyuria due to diabetes insipidus. A craniopharyngioma or another parasellar mass was suspected, an MRI showed an expansive suprasellar process with a cystic component with chiasm compression. A hormone panel showed corticotrophic and thyrotrophic deficiencies. Hormone replacement was started and the patient was referred for surgery. The immediate postoperative progressed well, although one month later she presented recurrence of the compressive symptoms (a headache and visual loss). She was submitted to second surgery. According to the pathology, the mass was identified as a suprasellar immature teratoma, with germ component, as well as cystic areas (ki67: 80%). In addition, tumor markers tests were requested: beta-HCG 5.47mIU/mL (<5.0), alpha-FP 3.1ng/mL (<7.0), DHL 635U/L (240-480). The patient was staged and referred to oncology unit that indicated radiotherapy, as a postoperative adjuvant therapy. At the most recent follow-up, approximately 9 months later, MRI shows a residual, stable tumor and patient presents with bitemporal hemianopsia. Conclusion: Intracranial germ cell tumors are uncommon, with only 15 cases of sellar-suprasellar teratoma described in the literature. It is important to recognize this entity in the differential diagnosis once they mimic many other lesions. Future reports on this rare location for a teratoma may help ascertain long-term outcomes. Reference: Chiloiro, S., Giampietro, A., Bianchi, A., & De Marinis, L. (2015). Clinical management of teratoma, a rare hypothalamic-pituitary neoplasia. Endocrine, 53(3), 636-642. doi:10.1007/s12020-015-0814-4

Preclinical Evaluation of CHF3381 as a Novel Antiepileptic Agent

CHF3381 [n-(2-indanyl)-glycinamide hydrochloride] has been selected on the basis of a screening program as the compound displaying the highest anticonvulsant activity in the maximal electroshock seizure (MES) test and the best therapeutic index with reference to the rotarod test in mice and rats. In this study, the antiepileptic activity and the behavioural toxicity of CHF3381 were characterised in multiple model systems. CHF3381 effectively prevented MES-induced convulsions when administered i.p. (ED50, 24 mg/kg and 7.5 mg/kg) or p.o. (ED50, 21 mg/kg and 21 mg/kg) in both mice and rats, respectively. The time course of oral anti-MES activity in the rat was related to the brain concentration profile of unchanged CHF3381. Interestingly, the brain drug levels were about 4-5 times higher than in plasma. CHF3381 was very effective in mice against picrotoxin-, and i.c.v. N-methyl-D-aspartate (NMDA)-induced hind limb tonic extension (ED50 Approximately/=10 mg/kg), but was a weaker antagonist of 4-amynopyridine- and bicuculline-induced tonic seizures (ED50 approximately/=100 mg/kg), and ineffective against pentylentetrazole- and picrotoxin-induced clonic seizures. CHF3381 antagonised the behavioural effects and lethality of i.p. administered NMDA (ED50 = 57 mg/kg p.o.), indicating that the compound may act as a functional NMDA antagonist. In keeping with this idea, CHF3381 weakly displaced [(3)H]-TCP from binding to NMDA receptor channels (Ki, 8.8 microM). In the rat amygdala kindling model, CHF3381 was more efficient against kindling development than against kindled seizures (minimally active dose = 80 vs. 120 mg/kg i.p). Furthermore, it significantly increased the seizure threshold in kindled rats at relatively low doses (40 mg/kg i.p.). In contrast with MK-801-induced hyperactivity, CHF3381 moderately reduced the spontaneous locomotor activity in mice at anticonvulsant doses. Toxic effects on motor performance (rotarod test) were found at high doses only (TD50 approximately/= 300 mg/kg p.o., congruent with 100 mg/kg i.p. in both mice and rats). Furthermore, CHF3381 did not impair passive avoidance and Morris water maze responding in the therapeutic range of doses. Finally, the development of tolerance after repeated doses was negligible. These data indicate that CHF3381 exerts anticonvulsant and antiepileptogenic effects in various seizure models and possesses good therapeutic window, with scarce propensity to cause neurological side-effects.

Comparative efficacy of a DA2/alpha2 agonist and a beta-blocker in reducing adrenergic drive and cardiac fibrosis in an experimental model of left ventricular dysfunction after coronary artery occlusion

Attenuation of neuroendocrine activation may be beneficial in congestive heart failure. Sympathetic nervous system overactivity can be reduced by receptors blockade or by reducing norepinephrine (NE) spillover. This study evaluated and compared the effects of a DA2-dopaminergic receptor/alpha2-adrenoceptor agonist (CHF-1024) and a beta1-adrenoreceptor antagonist in terms of hemodynamics, ventricular remodeling, beta-adrenergic drive, and cardiac fibrosis after myocardial infarction (MI) in rats. MI was induced by left coronary artery ligation in 213 rats, whereas 12 were left unoperated on. After 2 months, the operated-on animals were treated for 1 more month with CHF-1024 at either 0.33 mg/kg/day (low dose) or 1 mg/kg/day (high dose) or with metoprolol (10 mg/kg/day), delivered through implanted osmotic minipumps. Plasma concentration and urinary excretion of NE were measured before the rats were killed. Hemodynamic variables were measured and morphometric analysis was done on the diastole-arrested hearts to quantify left ventricular remodeling and interstitial collagen density. Metoprolol treatment tended to normalize LV end-diastolic pressure (LVEDP). CHF-1024 at either dose, and metoprolol, significantly reduced collagen deposition in LV of infarcted animals (from 8.8 +/- 0.5% LV area in vehicle-treated rats to 6.6 +/- 0.2% or 6.4 +/- 0.2% after the low or high dose of CHF-1024, respectively; p < 0.05). Similarly, CHF-1024 at either dose reduced the plasma concentration of NE (from 224 +/- 53 pg/ml to 60 +/- 7 pg/ml or 87 +/- 13 pg/ml; p < 0.05) and urinary excretion of NE in rats with MI, whereas beta-blockade did not affect these variables. In conclusion, CHF-1024 infused for 1 month to rats with LV dysfunction reduced heart rate, NE spillover, and collagen deposition, without unwanted effects, only appearing at the higher dose. Effective beta-blockade with metoprotol reduced LVEDP with no effects on heart function. Neither DA2/alpha2 stimulation nor beta-blockade altered LV remodeling after coronary artery ligation.

New method for the resolution of the enantiomers of 5,6-dihydroxy-2-methyl-aminotetralin by selective derivatization and HPLC analysis: application to biological fluids

A new chiral derivatization procedure for the HPLC resolution of chiral catecholamines and structurally related compounds is described. The homochiral reagent, (+)-(R)-1-phenylethyl isocyanate (RPEIC), was added to separate and quantitate the enantiomers of rac-5,6-dihydroxy-2-methyl-aminotetralin, the main metabolite of rac-5, 6-diisobutyryl-2-methyl-aminotetralin, a potent dopamine agonist, by reversed-phase HPLC analysis. To avoid catecholamine degradation in the basic reaction medium and to obtain the selective and quantitative derivatization of the amino group of the compound, the reversible complex formation between diphenylborinic acid (DPBA) and the catechol group, in alkaline medium, was performed before homochiral isocyanate addition. The RPEIC derivatization was completed in 30 min and then the DPBA complex was dissociated by adding dilute acid. The structure of intermediates and urea derivatives was confirmed by mass spectometry. The use of an electrochemical detector, operating in redox mode, allowed HPLC quantitation of enantiomers at the nanogram level in plasma and urine. The derivatization procedure is also suitable for other catecholamine-related compounds.

Simultaneous determination of levodopa methyl ester, levodopa, 3-O-methyldopa and dopamine in plasma by high-performance liquid chromatography with electrochemical detection

A new procedure is described for the simultaneous determination of levodopa methyl ester (LDME) and its biotransformation products levodopa (L-DOPA), 3-O-methyldopa (3-OMD) and dopamine (DA) in stabilized plasma samples, using reversed-phase high-performance liquid chromatography. A coulometric detector equipped with a dual-electrode system operating in the redox mode was used to simultaneously quantitate all compounds. This system generated a double signal monitored by a dual-channel acquisition data system and allowed quantitation of compounds at the nanogram level. The intra- and inter-assay precision varied in the 2.4-6.9% and 3.2-9.1% ranges respectively, whereas the recoveries were close to 85% for L-DOPA and 3-OMD and 70% for DA and LDME. Samples may be stored at -80 degrees C for 15 days before analysis. The method was applied to plasma samples after oral administration of LDME to rats, but it may also be suitable for human pharmacokinetic studies.

Selective method for plasma quantitation of the stereoisomers of a new aminotetralin by high-performance liquid chromatography with electrochemical detection

A high-performance liquid chromatographic method is described for the quantitation in plasma of the four stereoisomers of a new aminotetralin, (SRR, RSS)(SRS, RSR)-5,6-dimethoxy-2-[3'-(p-hydroxyphenyl)-3'-hydroxy-2'- propyl]aminotetralin (CHF 1255, internal code). After liquid-liquid extraction of the drug, separation was obtained after chiral derivatization with R-(+)-alpha-methylbenzyl isocyanate. The selective derivatization of the amino group was obtained by controlling the pH of the reaction medium at 7.5. The reaction was quantitative after a period of 16 h. The structures of the urea derivatives were confirmed by proton nuclear magnetic resonance spectroscopy and high-performance liquid chromatography with mass spectrometric detection. The use of an electrochemical detector, operating in the oxidative mode, allows the quantitation in plasma of all four urea derivatives at the nanogram level. The method was demonstrated to be precise, reproducible and applicable to pharmacokinetics studies after administration of the two epimeric racemates.

Evidence of pulmonary tropism of bamifylline and its main active metabolite

The extent of the extraplasmatic tropism of bamifylline (Bamifix) was evaluated in the rat and in man by assaying concentrations of bamifylline and of its main active metabolite AC-119 in lung tissue and plasma. After a single oral and intravenous administration of bamifylline in the rat, the ratio between pulmonary and plasma concentrations was between 2.0 and 3.2 for bamifylline, and between 4 and 15 for AC-119 during the observation period considered. On the other hand, the same ratios, calculated after the oral and intravenous administration of theophylline, ranged between 0.20 and 0.39. In studies on man, samples of plasma and lung tissue were obtained during surgery in subjects affected by pulmonary neoplasia and previously subjected to therapy with bamifylline according to the usual dosage scheme. The ratios between tissue and plasma concentrations, at the steady-state and in conditions of equilibrium between the compartments, were 9.4 for bamifylline and 34.7 for its active metabolite. The particular tissue tropism of bamifylline, that appears to be due to its high lipophilic character, could partly explain its high therapeutic index.