Molecular Dynamics Simulations of p97 Including Covalent, Allosteric and ATP-Competitive Inhibitors

Binary (nucleotide-protein dimer and hexamer complexes) and ternary (nucleotide-protein-inhibitor complexes) p97 complexes were subjected to molecular dynamics simulations in an attempt to further our understanding of the p97 protein oligomer domain stability and, more importantly, of the recently reported diverse molecular mechanisms of inhibition including allosteric, ATP-competitive and covalent inhibitors. Analysis of stable states following equilibration phases indicated a higher intrinsic stability of the homohexamer as opposed to the dimer, and of N-D1 domains as opposed to the D2 domain. The molecular dynamics of the proposed allosteric binding model reproduced important molecular interactions identified experimentally with high frequency throughout the trajectory. Observed conformational changes occurring in the D2 nucleotide binding site provided a novel bind-rearrange-react hypothesis of stepwise molecular events involved in the specific covalent inhibitor mode of action

New Aryl Hydrocarbon Receptor Homology Model Targeted To Improve Docking Reliability

The aryl hydrocarbon receptor (AhR) is a ligand-dependent, basic helix–loop–helix Per-ARNT-Sim (PAS) containing transcription factor that can bind and be activated by structurally diverse chemicals, including the toxic environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). As no experimentally determined structures of the AhR ligand binding domain (LBD) are available and previous homology models were only derived from <i>apo</i> template structures, we developed a new model based on <i>holo</i> X-ray structures of the hypoxia-inducible factor 2α (HIF-2α) PAS B domain, targeted to improve the accuracy of the binding site for molecular docking applications. We experimentally confirmed the ability of two HIF-2α crystallographic ligands to bind to the mAhR with relatively high affinity and demonstrated that they are AhR agonists, thus justifying the use of the <i>holo</i> HIF-2α structures as templates. A specific modeling/docking approach was proposed to predict the binding modes of AhR ligands in the modeled LBD. It was validated by comparison of the calculated and the experimental binding affinities of active THS ligands and TCDD for the mAhR and by functional activity analysis using several mAhR mutants generated on the basis of the modeling results. Finally the ability of the proposed approach to reproduce the different affinities of TCDD for AhRs of different species was confirmed, and a first test of its reliability in virtual screening is carried out by analyzing the correlation between the calculated and experimental binding affinities of a set of 14 PCDDs

Synthesis and conformational analysis of galactose-derived bicyclic scaffolds

Two novel galactose-derived bicyclic acetamides were synthesized. The conformational behavior of these cyclic acetamides in aqueous solution was fully investigated. The NMR spectroscopic data suggests that the pyran ring interconverts between two (C-4(1), S-1(3)) or three (C-4(1), S-1(3) and C-1(4)) conformations and molecular modelling studies allowed the structures' geometries to be defined. Three different force fields were used (Amber*, MM3* and OPLSAA) and fitting procedures were employed to reproduce the experimental (3)J(H-H) coupling constants and NOE contacts. Evaluation of the results established which of these three well-known force fields were the most reliable in reproducing the experimental observations and should therefore be used for analogous design studies. ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006

Wearable Heart Rate Monitoring Device Communicating in 5G ISM Band for IoHT

Advances in wearable device technology pave the way for wireless health monitoring for medical and non-medical applications. In this work, we present a wearable heart rate monitoring platform communicating in the sub-6GHz 5G ISM band. The proposed device is composed of an Aluminium Nitride (AlN) piezoelectric sensor, a patch antenna, and a custom printed circuit board (PCB) for data acquisition and transmission. The experimental results show that the presented system can acquire heart rate together with diastolic and systolic duration, which are related to heart relaxation and contraction, respectively, from the posterior tibial artery. The overall system dimension is 20 mm by 40 mm, and the total weight is 20 g, making this device suitable for daily utilization. Furthermore, the system allows the simultaneous monitoring of multiple subjects, or a single patient from multiple body locations by using only one reader. The promising results demonstrate that the proposed system is applicable to the Internet of Healthcare Things (IoHT), and particularly Integrated Clinical Environment (ICE) applications

Discovery of 2‑(Cyclohexylmethylamino)pyrimidines as a New Class of Reversible Valosine Containing Protein Inhibitors

Valosine-containing protein (VCP), also known as p97 or cdc48 in yeast, is a highly abundant protein belonging to the AAA ATPase family involved in a number of essential cellular functions, including ubiquitin–proteasome mediated protein degradation, Golgi reassembly, transcription activation, and cell cycle control. Altered expression of VCP has been detected in many cancer types sometimes associated with poor prognosis. Furthermore, VCP mutations are causative of some neurodegenerative disorders. In this paper we report the discovery, synthesis, and structure–activity relationships of substituted 2-aminopyrimidines, representing a new class of reversible VCP inhibitors. This class of compounds, identified in a HTS campaign against recombinant VCP, has been progressively expanded and manipulated to increase biochemical potency and gain cellular activity

IV thrombolysis plus thrombectomy versus IV thrombolysis alone for minor stroke with anterior circulation large vessel occlusion from the IRETAS and Italian SITS-ISTR cohorts

Introduction: The aim of this study was to compare the outcomes of patients treated with intravenous thrombolysis (IVT) &lt;4.5 h after symptom onset plus mechanical thrombectomy (MT) &lt;6 h with those treated with IVT alone &lt;4.5 h for minor stroke (NIHSS ≤5) with large vessel occlusion (LVO) in the anterior circulation. Patients and methods: Patients enrolled in the Italian Registry of Endovascular Treatment in Acute Stroke (IRETAS) and in the Italian centers included in the SITS-ISTR were analyzed. Results: Among the patients with complete data on 24-h ICH type, 236 received IVT plus MT and 382 received IVT alone. IVT plus MT was significantly associated with unfavorable shift on 24-h ICH types (from no ICH to PH-2) (OR, 2.130; 95% CI, 1.173-3.868; p=0.013) and higher rate of PH (OR, 4.363; 95% CI, 1.579-12.055; p=0.005), sICH per ECASS II definition (OR, 5.527; 95% CI, 1.378-22.167; p=0.016), and sICH per NINDS definition (OR, 3.805; 95% CI, 1.310-11.046; p=0.014). Among the patients with complete data on 3-month mRS score, 226 received IVT plus MT and 262 received IVT alone. No significant difference was reported between IVT plus MT and IVT alone on mRS score 0-1 (72.1% versus 69.1%), mRS score 0-2 (79.6% versus 79%), and death (6.2% versus 6.1%). Conclusions: Compared with IVT alone, IVT plus MT was associated with unfavorable shift on 24-h ICH types and higher rate of 24-h PH and sICH in patients with minor stroke and LVO in the anterior circulation. However, no difference was reported between the groups on 3-month functional outcome measures

Stroke with large vessel occlusion in the posterior circulation: IV thrombolysis plus thrombectomy versus IV thrombolysis alone

: Efficacy and safety of mechanical thrombectomy (MT) for stroke with posterior circulation large vessel occlusion (LVO) is still under debate. We aimed to compare the outcomes of stroke patients with posterior circulation LVO treated with intravenous thrombolysis (IVT) (< 4.5 h after symptom onset) plus MT < 6 h after symptom onset with those treated with IVT alone (< 4.5 h after symptom onset). Patients enrolled in the Italian Registry of Endovascular Treatment in Acute Stroke (IRETAS) and in the Italian centers included in the SITS-ISTR were analysed. We identified 409 IRETAS patients treated with IVT plus MT and 384 SITS-ISTR patients treated with IVT alone. IVT plus MT was significantly associated with higher rate of sICH (ECASS II) compared with IVT alone (3.1 vs 1.9%; OR 3.984, 95% CI 1.014-15.815), while the two treatments did not differ significantly in 3-month mRS score ≤ 3 (64.3 vs 74.1%; OR 0.829, 95% CI 0.524-1.311). In 389 patients with isolated basilar artery (BA) occlusion, IVT plus MT was significantly associated with higher rate of any ICH compared with IVT alone (9.4 vs 7.4%; OR 4.131, 95% CI 1.215-14.040), while two treatments did not differ significantly in 3-month mRS score ≤ 3 and sICH per ECASS II definition. IVT plus MT was significantly associated with higher rate mRS score ≤ 2 (69.1 vs 52.1%; OR 2.692, 95% CI 1.064-6.811) and lower rate of death (13.8 vs 27.1%; OR 0.299, 95% CI 0.095-0.942) in patients with distal-segment BA occlusion, while two treatments did not differ significantly in 3-month mRS score ≤ 3 and sICH per ECASS II definition. IVT plus MT was significantly associated with lower rate of mRS score ≤ 3 (37.1 vs 53.3%; OR 0.137, 0.009-0.987), mRS score ≤ 1 (22.9 vs 53.3%; OR 0.066, 95% CI 0.006-0.764), mRS score ≤ 2 (34.3 vs 53.3%; OR 0.102, 95% CI 0.011-0.935), and higher rate of death (51.4 vs 40%; OR 16.244, 1.395-89.209) in patients with proximal-segment BA occlusion. Compared with IVT alone, IVT plus MT was significantly associated with higher rate of sICH per ECASS II definition in patients with stroke and posterior circulation LVO, while two treatment groups did not differ significantly in 3-month mRS score ≤ 3. IVT plus MT was associated with lower rate of mRS score ≤ 3 compared with IVT alone in patients with proximal-segment BA occlusion, whereas no significant difference was found between the two treatments in primary endpoints in patients isolated BA occlusion and in the other subgroups based on site occlusion