New insight into the central benzodiazepine receptor-ligand interactions: design, synthesis, biological evaluation, and molecular modeling of 3-substituted 6-phenyl-4H-imidazo[1,5-a][1,4]benzodiazepines and related compounds

3-Substituted 6-phenyl-4H-imidazo[1,5-a][1,4]benzodiazepines and related compounds were synthesized as central benzodiazepine receptor (CBR) ligands. Most of the compounds showed high affinity for bovine and human CBR, their K(i) values spanning from the low nanomolar to the submicromolar range. In particular, imidazoester 5f was able to promote a massive flow of (36)Cl(-) in rat cerebrocortical synaptoneurosomes overlapping its efficacy profile with that of a typical full agonist. Compound 5f was then examined in mice for its pharmacological effects where it proved to be a safe anxiolytic agent devoid of the unpleasant myorelaxant and amnesic effects of the classical 1,4-benzodiazepines. Moreover, the selectivity of some selected compounds has been assessed in recombinant α(1)β(2)γ(2)L, α(2)β(1)γ(2)L, and α(5)β(2)γ(2)L human GABA(A) receptors. Finally, some compounds were submitted to molecular docking calculations along with molecular dynamics simulations in the Cromer's GABA(A) homology model.     

Non-nucleoside inhibitors of human adenosine kinase: synthesis, molecular modeling, and biological studies

Adenosine kinase (AK) catalyzes the phosphorylation of adenosine (Ado) to AMP by means of a kinetic mechanism in which the two substrates Ado and ATP bind the enzyme in a binary and/or ternary complex, with distinct protein conformations. Most of the described inhibitors have Ado-like structural motifs and are nonselective, and some of them (e.g., the tubercidine-like ligands) are characterized by a toxic profile. We have cloned and expressed human AK (hAK) and searched for novel non-substrate-like inhibitors. Our efforts to widen the structural diversity of AK inhibitors led to the identification of novel non-nucleoside, noncompetitive allosteric modulators characterized by a unique molecular scaffold. Among the pyrrolobenzoxa(thia)zepinones (4a-qq) developed, 4a was identified as a non-nucleoside prototype hAK inhibitor. 4a has proapoptotic efficacy, slight inhibition of short-term RNA synthesis, and cytostatic activity on tumor cell lines while showing low cytotoxicity and no significant adverse effects on short-term DNA synthesis in cells.     

Synthesis and antiplasmodial activity of bicyclic dioxanes as simplified dihydroplakortin analogues

Here we report the synthesis and evaluation of antiplasmodial activity of a novel series of bicyclic peroxides inspired by the marine natural compound dihydroplakortin. We developed a synthetic strategy leading to the dihydroplakortin-related peroxides in only a few steps. The in vitro antiplasmodial potency of the peroxides was similar to, or greater than, that of the reference natural compound, and structure-activity relationship studies revealed several key structural requirements for activity and potency.     

25I-NBOH: a new potent serotonin 5-HT<Subscript>2A</Subscript> receptor agonist identified in blotter paper seizures in Brazil

A new potent serotonin 5-HT_2A receptor agonist was identified in blotter papers by several state level forensic laboratories in Brazil. The 25I-NBOH is a labile molecule, which fragments into 2C-I when analyzed by routine seized material screening gas chromatography (GC) methods. GC–mass spectrometry (MS), liquid chromatography–quadrupole time-of-flight-MS, and Fourier transform infrared and nuclear magnetic resonance analyses were performed to complete molecular characterization. Individual doses range from 300 to 1000 μg. Despite its being a potent 5-HT_2A receptor agonist, 25I-NBOH is neither registered in the United Nations Office on Drugs and Crime (UNODC) nor classified as a scheduled substance in most countries. Sweden and Brazil seem to be the only countries to control 25I-NBOH. To our knowledge, this is the first scientific report dealing with identification of 25I-NBOH in actual seizures.     

How to approach the pediatric flatfoot

The most difficult aspect regarding treatment of the pediatric flatfoot is understanding who needs surgery,when it is necessary, and what procedure to be done.A thorough history, clinical examination, and imaging should be performed to guide the surgeon through an often complex treatment path. Surgical technique can be divided in three categories: Soft tissue, bony,and arthroereisis. This paper will describe the jointpreserving techniques and their application to treat the pediatric flatfoot deformity.     

Resistive Switching Phenomenon Observed in Self-Assembled Films of Flame-Formed Carbon-TiO2 Nanoparticles

Nanostructured films of carbon and TiO₂ nanoparticles have been produced by means of a simple two-step procedure based on flame synthesis and thermophoretic deposition. At first, a granular carbon film is produced on silicon substrates by the self-assembling of thermophoretically sampled carbon nanoparticles (CNPs) with diameters of the order of 15 nm. Then, the composite film is obtained by the subsequent thermophoretic deposition of smaller TiO₂ nanoparticles (diameters of the order of 2.5 nm), which deposit on the surface and intercalate between the carbon grains by diffusion within the pores. A bipolar resistive switching behavior is observed in the composite film of CNP-TiO₂. A pinched hysteresis loop is measured with SET and RESET between low resistance and high resistance states occurring for the electric field of 1.35 × 10⁴ V/cm and 1.5 × 10⁴ V/cm, respectively. CNP-TiO₂ film produced by flame synthesis is initially in the low resistive state and it does not require an electroforming step. The resistance switching phenomenon is attributed to the formation/rupture of conductive filaments through space charge mechanism in the TiO₂ nanoparticles, which facilitate/hinder the electrical conduction between carbon grains. Our findings demonstrate that films made of flame-formed CNP-TiO₂ nanoparticles are promising candidates for resistive switching components.     

Surgical resection of liver metastases from breast cancer

The aim of this review is to define the relevance of surgical resection for liver metastasis of breast cancer. We report the rationale for hepatic surgery of liver metastasis, the survival prognosis factors for these patients, and the influence of liver resection on overall survival. The aim of this surgery is not only the local control, but also general control of the disease by preventing the selection of resistant tumor cell clones. Adjuvant therapies remain necessary for general control of the disease. While preoperative detection of small intra hepatic lesions remains difficult, MRI and preoperative ultrasound may help.     

Risk factors for unprovoked epileptic seizures in multiple sclerosis: a systematic review and meta-analysis

The role of different factors in influencing the risk of seizures during multiple sclerosis (MS) is not known. To perform a systematic review and meta-analysis of risk factors for epilepsy during MS. Pubmed, Google scholar, and Scopus databases were searched. Articles published in English (1986–2016) were included. Nine studies were included (3 retrospective cohort and 6 case–control) enrolling 2845 MS patients (217 with epilepsy; 7.6%). MS patients with epilepsy had a younger age at onset compared to MS patients without seizures (difference in means = ?5.42 years, 95% CI ?7.19 to ?3.66, p < 0.001). Mean EDSS value at inclusion tended to be higher in patients with epilepsy, without reaching statistical significance (difference in means = 0.45, 95% CI ?0.01 to 0.91, p = 0.054). No differences were observed in sex distribution (OR = 0.94, 95% CI 0.51–1.72, p = 0.83) and clinical form (OR = 1.03, 95% CI 0.33–3.21, p = 0.96). Two studies evaluated presence and number of cortical lesions as a risk factor for epilepsy in MS using different MRI techniques: in one study, cortical lesions were more frequently observed in patients with epilepsy (OR = 7.06, 95% CI 2.39–20.8; p < 0.001). In the other, cortico-juxtacortical lesions were more frequently observed in patients with epilepsy (OR = 2.6, 95% CI 1.0–6.5; p = 0.047). Studies about risk factors for epilepsy during MS are heterogeneous. Compared to MS patients without seizures, patients with epilepsy have an earlier MS onset and a higher EDSS score after similar disease duration. Clinical form of MS and sex do not predict the appearance of seizures.