Gap Opening in Double-Sided Highly Hydrogenated Free-Standing Graphene.

Conversion of free-standing graphene into pure graphane─where each C atom is sp3 bound to a hydrogen atom─has not been achieved so far, in spite of numerous experimental attempts. Here, we obtain an unprecedented level of hydrogenation (≈90% of sp3 bonds) by exposing fully free-standing nanoporous samples─constituted by a single to a few veils of smoothly rippled graphene─to atomic hydrogen in ultrahigh vacuum. Such a controlled hydrogenation of high-quality and high-specific-area samples converts the original conductive graphene into a wide gap semiconductor, with the valence band maximum (VBM) ∼ 3.5 eV below the Fermi level, as monitored by photoemission spectromicroscopy and confirmed by theoretical predictions. In fact, the calculated band structure unequivocally identifies the achievement of a stable, double-sided fully hydrogenated configuration, with gap opening and no trace of π states, in excellent agreement with the experimental results.

Atorvastatin treatment and carotid plaque morphology in first-ever atherosclerotic transient ischemic attack/stroke: a case-control study.

BACKGROUND: A relationship between echolucency of carotid plaques and the consequent risk of ipsilateral ischemic stroke has been observed. An aggressive lipid-lowering therapy may increase the echogenicity of carotid plaque in patients with elevated low-density lipoprotein cholesterol levels. The aim of this study is to prospectively evaluate the long-term effect of high-dose atorvastatin on carotid plaque morphology in patients with first-ever transient ischemic attack or stroke. METHODS: All patients with symptomatic first ischemic atherosclerotic cerebrovascular event occurred within the previous 10 days were enrolled. Carotid Doppler ultrasound of the neck vessels with 7-11 MHz probe for the definition of the atherosclerotic carotid framework was performed. The analysis of the gray-scale median (GSM) of each plate was carried out with image processing software. RESULTS: A total of 240 symptomatic plaques were included and divided into 3 groups: 80 in group A (atorvastatin 80 mg), 80 in group B (atorvastatin 40 mg), and 80 to group C (no atorvastatin). GSM score increases significantly more extensive in group A than in group B (+48.65 vs. +39.46, P < .02) and group C (+48.65 vs. 19.3, P = .0002). An inverse association between reduction of low-density lipoprotein and the increase in the GSM score (r = -.456, P = .007) has been observed. Moreover, the reduction of high-sensitive C-reactive protein correlates inversely with the increase of the GSM (r = -.398, P = .021). CONCLUSIONS: Dose-dependent effect of atorvastatin on symptomatic carotid plaque morphology may suggest a specific role of this drug in the atherosclerotic stroke prevention.

Depression, anxiety and alexithymia symptoms are major determinants of health related quality of life (HRQoL) in cirrhotic patients.

HRQoL is impaired in cirrhosis. Establishing the relevance of depression, anxiety, alexithymia and cirrhosis stage on the patients' HRQoL. Sixty cirrhotics underwent a neuropsychological assessment, including ZUNG-SDS, STAI Y1-Y2 and TAS-20. Minimal hepatic encephalopathy (MHE) was detected by PHES, HRQoL by Short-Form-36 (SF-36). Depression was detected in 34 patients (57 %, 95%CI = 44-70 %), state-anxiety in 16 (27 %, 95%CI = 15-38 %), trait-anxiety in 17 (28 %, 95%CI = 17-40 %), alexithymia in 14 (31 % 95%CI = 16-46 %) and MHE in 22 (37 %, 95%CI = 24-49 %). Neuropsychological symptoms were unrelated to cirrhosis stage, hepatocellular carcinoma or MHE. A significant correlation was observed among psychological test scores and summary components of SF-36. At multiple linear regression analysis including Child-Pugh and MELD scores, previous-HE and the psychological test scores as possible covariates, alexithymia and depression as well as to the Child-Pugh score were significantly related to the SF-36 mental component; while trait-anxiety was the only variable significantly and independently related to the SF-36 physical component. Depression, state and trait-anxiety and alexithymia symptoms are frequent in cirrhotics and are among the major determinants of the altered HRQoL.

Hypothalamic dysfunctions as a late consequence of surgical opening of the lamina terminalis. A controversial hypothesis.

BACKGROUND: Opening of the lamina terminalis is often used in surgery of the optico-chiasmatic region. Consequently, alteration of cerebral-spinal fluid (CSF) dynamics can occur after this manoeuvre, thus potentially translating into clinical complications. Herein, we describe 2 cases in which clinically relevant hypothalamic dysfunctions developed after few days opening of the lamina terminalis both patients showed mild to moderate preoperative hydrocephalus which improved postoperatively. CASES DESCRIPTION: In a patient with ruptured aneurysm of the basilar bifurcation, opening of the lamina terminalis was performed prior to acute-stage clipping. On postoperative day 7th, the patient developed significant subdural hygroma, mild disturbances of consciousness and increase of ADH concentration. These clinical features resolved only following subdural hygroma drainage and ventricular-peritoneal shunting. One previously operated patient in whom the lamina terminalis had been opened to remove a sizeable parasellar tumour showed a similar post-operative course. In this patient, sole subdural hygroma drainage was not an effective treatment, and the patient died subsequently for complications related to long-standing, though mild, hypothalamic dysfunction. CONCLUSIONS: Our experience may suggest that hypothalamic dysfunctions should be reminded as a possible, although rare, complication following the opening of the lamina terminalis. This clinical condition, if not properly managed, may contribute to trigger severe life-threatening complications.

Deuterium Adsorption on Free-Standing Graphene.

A suitable way to modify the electronic properties of graphene-while maintaining the exceptional properties associated with its two-dimensional (2D) nature-is its functionalisation. In particular, the incorporation of hydrogen isotopes in graphene is expected to modify its electronic properties leading to an energy gap opening, thereby rendering graphene promising for a widespread of applications. Hence, deuterium (D) adsorption on free-standing graphene was obtained by high-energy electron ionisation of D2 and ion irradiation of a nanoporous graphene (NPG) sample. This method allows one to reach nearly 50 at.% D upload in graphene, higher than that obtained by other deposition methods so far, towards low-defect and free-standing D-graphane. That evidence was deduced by X-ray photoelectron spectroscopy of the C 1s core level, showing clear evidence of the D-C sp3 bond, and Raman spectroscopy, pointing to remarkably clean and low-defect production of graphane. Moreover, ultraviolet photoelectron spectroscopy showed the opening of an energy gap in the valence band. Therefore, high-energy electron ionisation and ion irradiation is an outstanding method for obtaining low defect D-NPG with a high D upload, which is very promising for the fabrication of semiconducting graphane on large scale.

Ultrasonographic evaluation of cerebral arterial and venous haemodynamics in multiple sclerosis: a case-control study.

OBJECTIVE: Although recent studies excluded an association between Chronic Cerebrospinal Venous Insufficiency and Multiple Sclerosis (MS), controversial results account for some cerebrovascular haemodynamic impairment suggesting a dysfunction of cerebral autoregulation mechanisms. The aim of this cross-sectional, case-control study is to evaluate cerebral arterial inflow and venous outflow by means of a non-invasive ultrasound procedure in Relapsing Remitting (RR), Primary Progressive (PP) Multiple Sclerosis and age and sex-matched controls subjects. MATERIAL AND METHODS: All subjects underwent a complete extra-intracranial arterial and venous ultrasound assessment with a color-coded duplex sonography scanner and a transcranial doppler equipment, in both supine and sitting position by means of a tilting chair. Basal arterial and venous morphology and flow velocities, postural changes in mean flow velocities (MFV) of middle cerebral arteries (MCA), differences between cerebral venous outflow (CVF) in clinostatism and in the seated position (ΔCVF) and non-invasive cerebral perfusion pressure (CPP) were evaluated. RESULTS: 85 RR-MS, 83 PP-MS and 82 healthy controls were included. ΔCVF was negative in 45/85 (52.9%) RR-MS, 63/83 (75.9%) PP-MS (p = 0.01) and 11/82 (13.4%) controls (p<0.001), while MFVs on both MCAs in sitting position were significantly reduced in RR-MS and PP-MS patients than in control, particularly in EDSS ≥ 5 subgroup (respectively, 42/50, 84% vs. 66/131, 50.3%, p<0.01 and 48.3 ± 2 cm/s vs. 54.6 ± 3 cm/s, p = 0.01). No significant differences in CPP were observed within and between groups. CONCLUSIONS: The quantitative evaluation of cerebral blood flow (CBF) and CVF and their postural dependency may be related to a dysfunction of autonomic nervous system that seems to characterize more disabled MS patients. It's not clear whether the altered postural control of arterial inflow and venous outflow is a specific MS condition or simply an "epiphenomenon" of neurodegenerative events.

Esophageal cancer presenting as a brain metastasis: A case report.

Carcinoma of unknown primary origin (CUP) is defined as the histological diagnosis of metastasis without the detection of a primary tumor. The incidence of CUP in all patients with a malignant disease has been reported to be between 3 and 15%. Esophageal cancer is the third most common type of cancer of the digestive tract and the seventh most common cause of cancer-related mortality worldwide. The overall incidence of the disease is highest in males >50 years old. Brain metastases have been reported in only 1.7-3.6% of all patients with different types of esophageal cancer. Brain metastasis as the presenting form of esophageal carcinoma is highly uncommon. The present study reports the case of a patient with an unknown primary tumor who presented with a cerebral metastasis, without extra-neurological symptoms. The CUP was subsequently diagnosed as an esophageal carcinoma.

Posttraumatic glioma: report of a case.

For a long time, head injury has been considered as a possible causative factor for later development of brain tumors. However, the actual role of previous head trauma in the pathogenesis of intracranial tumors is still a matter of debate, also due to the possible medico-legal implications. Some authors have suggested several criteria for establishing a possible causal relationship between the aforementioned factors. We report a case of a left posterior paraventricular high-grade glioma which developed 20 years after a posttraumatic hematoma occurring in the same area. This case is reported in detail and the relevant literature is reviewed.

Is "mini-invasive" technique for iliac crest harvesting an alternative to cervical cage implant? An overview of a large personal experience.

BACKGROUND: Autograft bone provides an excellent substrate for multilevel arthrodesis after anterior discectomy and is inexpensive. However, the use of tricortical bone could increase the discomfort for the patient. METHODS: We reviewed cases of cervical disc diseases operated on by a single neurosurgeon (AS), within the period June 2000-December 2011. A total of 221 patients were considered for the present study; 109 female, 112 male, averaging 49 years of age. Only patients who could be followed up for at least one year were included in the present study. The grafts obtained with the technique described are bi- (and not tri-) cortical, and always of sufficient size in order to fit two spaces if necessary. RESULTS: The technique is not associated with long-term significant donor site pain except for a striking minority of patients, it shortens the hospital stay, it offers comparable results to the published surgical series in which cage and/or modern implants are used. CONCLUSIONS: Autograft bone can be reasonably considered as one of the possible alternatives to be used in the surgical management of cervical disk disease.