Use of a common European approach for nanomaterials’ testing to support regulation: a case study on titanium and silicon dioxide representative nanomaterials

The European Union (EU) continuously takes ensuring the safe use of manufactured nanomaterials (MNMs) in consumer products into consideration. The application of a common approach for testing MNMs, including the use of optimized protocols and methods’ selection, becomes increasingly important to obtain reliable and comparable results supporting the regulatory framework. In the present study, we tested four representative MNMs, two titanium dioxides (NM100 and NM101) and two silicon dioxides (NM200 and NM203), using the EU FP7-NANoREG approach, starting from suspension and dispersion preparations, through to their characterization and final evaluation of biological effects. MNM dispersions were prepared following a refined NANOGENOTOX protocol and characterized by dynamic light scattering (DLS) in water/bovine serum albumin and in media used for in vitro testing. Potential genotoxic effects were evaluated on human bronchial BEAS-2B cells using micronucleus and Comet assays, and pro-inflammatory effects by cytokines release. Murine macrophages RAW 264.7 were used to detect potential innate immune responses using two functional endpoints (pro-inflammatory cytokines and nitric oxide [NO] production). The interaction of MNMs with RAW 264.7 cells was studied by electron microscopy. No chromosomal damage and slight DNA damage and an oxidative effect, depending on MNMs, were observed in bronchial cells. In murine macrophages, the four MNMs directly induced tumor necrosis factor α or interleukin 6 secretion, although at very low levels; lipopolysaccharide-induced NO production was significantly decreased by the titania and one silica MNM. The application of this approach for the evaluation of MNM biological effects could be useful for both regulators and industries.     

Improving molecular diagnosis in epilepsy by a dedicated high-throughput sequencing platform

We analyzed by next-generation sequencing (NGS) 67 epilepsy genes in 19 patients with different types of either isolated or syndromic epileptic disorders and in 15 controls to investigate whether a quick and cheap molecular diagnosis could be provided. The average number of nonsynonymous and splice site mutations per subject was similar in the two cohorts indicating that, even with relatively small targeted platforms, finding the disease gene is not an univocal process. Our diagnostic yield was 47% with nine cases in which we identified a very likely causative mutation. In most of them no interpretation would have been possible in absence of detailed phenotype and familial information. Seven out of 19 patients had a phenotype suggesting the involvement of a specific gene. Disease-causing mutations were found in six of these cases. Among the remaining patients, we could find a probably causative mutation only in three. None of the genes affected in the latter cases had been suspected a priori. Our protocol requires 8–10 weeks including the investigation of the parents with a cost per patient comparable to sequencing of 1–2 medium-to-large-sized genes by conventional techniques. The platform we used, although providing much less information than whole-exome or whole-genome sequencing, has the advantage that can also be run on ‘benchtop'' sequencers combining rapid turnaround times with higher manageability.     

The impact of radiological equipment on patient radiation exposure during endovascular aortic aneurysm repair

Objectives

To compare the patient radiation dose during endovascular aortic aneurysm repair (EVAR) using different types of radiological systems: a mobile fluoroscopic C-arm, mobile angiographic and fixed angiographic equipment.

Methods

Dose–area products (DAP) were obtained from a retrospective study of 147 consecutive patients, subjected to 153 EVAR procedures during a 3.5-year period. On the basis of these data, entrance surface dose (ESD) and effective dose (ED) were calculated. EVARs were performed using a fluoroscopic C-arm, mobile or fixed angiographic equipment in 79, 26 and 48 procedures, respectively.

Results

Fluoroscopy times were essentially equivalent for all the systems, ranging from 15 to 19?min. The clinical outcomes were not significantly different among the systems. Statistically significant differences among radiological equipment grouping were found for DAP (mobile C-arm: 32?±?20?Gy?cm²; mobile angiography: 362?±?164?Gy?cm²; fixed angiography: 464?±?274?Gy?cm²; P?<?10^?6), for ESD (mobile C-arm: 0.18?±?0.11?Gy; mobile angiography: 2.0?±?0.8?Gy; fixed angiography: 2.5?±?1.5?Gy; P?<?10^?6) and ED (mobile C-arm: 6.2?±?4.5?mSv; mobile angiography: 64?±?26?mSv; fixed angiography: 129?±?76?mSv; P?<?10^?6).

Conclusions

Radiation dose in EVAR is substantially less with a modern portable C-arm than with a fixed or mobile dedicated angiographic system.

Key Points

? Fluoroscopy during endovascular aortic aneurysm repair can impart a substantial radiation dose. ? Radiation doses during EVAR are higher when using mobile/fixed angiographic systems. ? Mobile C-arm fluoroscopy imparts a lower dose with an equivalent clinical outcome. ? Procedures need to be dose-optimised when using mobile/fixed angiographic systems.     

β Blockers for Prevention of Exercise-Induced Left Ventricular Outflow Tract Obstruction in Patients With Hypertrophic Cardiomyopathy

Whether treatment with β blockers (BBs) is of benefit to patients with hypertrophic cardiomyopathy (HC) and provocable outflow obstruction (with none or with only mild heart failure symptoms) is largely unresolved. Thus, we prospectively studied 27 patients with HC (age 36 ± 15 years; 81% men) with New York Heart Association class I or II, without obstruction at rest, but with exercise-induced left ventricular outflow tract (LVOT) gradient of ≥30 mm Hg. Patients underwent exercise echocardiography at baseline and after treatment with nadolol (n = 18; 40 to 80 mg/day) or bisoprolol (n = 9; 5 to 10 mg/day), according to a prespecified protocol. Without the BBs, the postexercise LVOT gradient was 87 ± 29 mm Hg and >50 mm Hg in 25 patients (93%). After a 12 ± 4-month period of BB treatment, the postexercise LVOT gradient had decreased to 36 ± 22 mm Hg (p <0.001) and was virtually abolished (to 0 or <30 mm Hg) in 14 patients (52%), substantially blunted (≥20 mm Hg reduction) in 9 (33%), and unchanged in only 4 (15%). Severe postexercise obstruction (range 58 to 80 mm Hg) persisted in 6 patients (22% compared to 93% without BBs; p <0.001). Nonresponders (residual postexercise gradient of ≥30 mm Hg with BBs) were characterized by an increased body mass index (hazard ratio 2.03/1 kg/m(2), 95% confidence interval 1.2 to 3.4; p <0.05). In conclusion, in patients with HC with mild or no symptoms, treatment with BBs can prevent the development of LVOT obstruction triggered by physiologic exercise. These findings provide a rationale for the novel strategy of early prophylactic pharmacologic treatment with standard, well-tolerated doses of BBs in physically active patients with provocable gradients, aimed at effective prevention of the hemodynamic burden associated with dynamic obstruction.     

Increased erythrocyte glutathione peroxidase activity and serum tumor necrosis factor-alpha in HIV-infected patients: relationship to on-going prothrombotic state

A condition of oxidative stress, due to perturbation of oxidant/antioxidant balance, has been suggested to play a role not only in the pathogenesis of human immunodeficiency virus (HIV) infection, but also in the promotion of a thrombophilic condition. Because various hemostatic dysfunctions usually considered as risk factors for thrombotic events were reported in HIV infection, this study was undertaken to investigate whether the oxidative phenomenon could promote a prothrombotic state in such condition. Erythrocyte glutathione peroxidase (GSH-Px), the major free-radical scavenger enzyme, and serum tumor necrosis factor-alpha (TNF-alpha) were evaluated in 33 consecutive HIV-infected out-patients and 35 matched HIV-negative healthy controls at a distance of any acute episode. Thrombin generation was explored by measuring the plasma levels of prothrombin fragment 1 + 2 (F1 + 2), whereas fibrin degradation products (D-dimer) and plasminogen activator inhibitor (PAI-1) activity were evaluated as indices of plasmin activity and fibrinolytic derangement. The anticoagulant pathway was investigated by measuring the plasma levels of antithrombin and protein C. Erythrocyte GSH-Px activity and serum TNF-alpha were significantly higher in HIV-infected patients when compared to controls. F1 + 2, D-dimer, and PAI-1 activity were increased in HIV-infected patients by comparison with controls. Normal antithrombin, but decreased protein C, was instead detected in HIV-infected patients. In the latter patients, serum TNF-alpha negatively correlated with both erythrocyte GSH-Px activity and plasma D-dimer. On the other hand, a positive correlation was shown between F1 + 2 and D-dimer and between D-dimer and GSH-Px activity. Furthermore, a trend toward increasing levels of GSH-Px with increasing PAI-1 activity was reported. These findings suggest a relationship between erythrocyte oxidative stress and the hypercoagulable condition during HIV infection.     

Tumor necrosis factor alpha levels in serum and cerebrospinal fluid of patients with AIDS.

We used a sensitive enzyme-linked immunosorbent assay technique to measure tumor necrosis factor alpha (TNF alpha) levels in serum and cerebrospinal fluid (CSF) samples from 30 patients infected with human immunodeficiency virus type 1 and from 10 normal controls. We found detectable levels of TNF alpha in 19 of 30 CSF and in 17 of 30 serum samples. The values of TNF alpha ranged between 20-90 pg/ml. All the patients had overt AIDS. More elevated TNF alpha levels in CSF correlate with focal damage within the central nervous system (p less than 0.01). Our results suggest that an intrathecal production of TNF alpha may occur during active inflammation in course of AIDS.     

Spasm of arm arteries due to ergotamine tartrate. A case report

Ergotamine tartrate and caffeine has been widely prescribed for the prevention and treatment of migraine headaches. Rarely the ergotamine can cause symptoms of peripheral vascular insufficiency, often concerning the lower extremities. A case report of bilateral severe ischemia to the upper limbs, caused by a chronic assumption of ergotamine tartrate is presented.