Highly luminescent scintillating hetero-ligand MOF nanocrystals with engineered Stokes shift for photonic applications.

Large Stokes shift fast emitters show a negligible reabsorption of their luminescence, a feature highly desirable for several applications such as fluorescence imaging, solar-light managing, and fabricating sensitive scintillating detectors for medical imaging and high-rate high-energy physics experiments. Here we obtain high efficiency luminescence with significant Stokes shift by exploiting fluorescent conjugated acene building blocks arranged in nanocrystals. Two ligands of equal molecular length and connectivity, yet complementary electronic properties, are co-assembled by zirconium oxy-hydroxy clusters, generating crystalline hetero-ligand metal-organic framework (MOF) nanocrystals. The diffusion of singlet excitons within the MOF and the matching of ligands absorption and emission properties enables an ultrafast activation of the low energy emission in the 100 ps time scale. The hybrid nanocrystals show a fluorescence quantum efficiency of ~60% and a Stokes shift as large as 750 meV (~6000 cm-1), which suppresses the emission reabsorption also in bulk devices. The fabricated prototypal nanocomposite fast scintillator shows benchmark performances which compete with those of some inorganic and organic commercial systems.

Fluorinated porous organic frameworks for improved CO2 and CH4 capture.

A porous 3D selectively fluorinated framework (F-PAF1), robust yet flexible and with a surface area of 2050 m2 g-1, was synthesised by condensation of an ad hoc prepared fluorinated tetraphenylmethane (TPM) monomer to ensure homogenously distributed C-F dipoles in the swellable architecture. Tetradentate TPM was also the comonomer for the reaction with fluorinated difunctional monomers to obtain frameworks (FMFs) with a controlled amount of regularly spaced reorientable C-F dipoles. The isosteric heat of adsorption of CO2 was increased by 53% by even moderate C-F dipole insertion, with respect to the non-fluorinated frameworks. CO2/N2 selectivity was also increased up to a value of 50 for the difluoro-containing comonomer. Moreover, methane shows optimal interaction energies of 24 kJ mol-1.

Expandable porous organic frameworks with built-in amino and hydroxyl functions for CO2 and CH4 capture.

The synthesis of porous organic 3D frameworks, wherein amine, hydroxyl and Li-alkoxide functions were built directly on the monomer-unit carbon core, realizes improved interactions with target gases. CO2 was retained by the amine group with a remarkable energy of 54 kJ mol-1, while 2D MAS NMR provided rare evidence of amine-to-gas short-distance interactions. Frameworks containing hydroxyl and Li-alkoxide functions show optimal interaction energies with CH4 of up to 25 kJ mol-1. The light network of 3-branch building units ensures the expandability of the nano-sponges.

Porous dipeptide crystals as volatile-drug vessels.

Porous crystalline dipeptides absorb, reversibly from the gas phase, a series of volatile fluorinated ethers in use as anesthetics. Their vapor pressure was considerably reduced, with favorable guest capture and release. Variable channel sizes were customized for selective sorption and pressure thresholds were observed in the narrowest pores. 1H, 13C and 19F MAS NMR coupled with ab initio conformational analysis and grand canonical Monte Carlo simulations highlight the guest loading and arrangement adopted in the congruent nanochannels, suggesting how the anesthetics can accommodate in biochemical receptors.

CO2 regulates molecular rotor dynamics in porous materials.

A crystalline hydrogen-bonded framework with permanent porosity, built by rod-like struts and engineered to bear ultra-fast molecular rotors between two triple bonds, offers the possibility of controlling the rotational rates upon CO2 adsorption. CO2 enters the pores from the gas phase and reduces the rotational rates from the extremely fast regime of 107 Hz at 216 K to 105 Hz. The CO2-rotor interaction was evident from the 2H NMR response to the dynamics of the rotors in contact with CO2 in the crystal structure.

Thromboaspiration technique as first approach for endovascular treatment of acute ischemic stroke: initial experience at nine Italian stroke centers.

BACKGROUND AND PURPOSE: Aspiration thrombectomy of large vessel occlusions has made a comeback among recanalization techniques thanks to recent advances in catheter technology resulting in faster recanalization and promising clinical results when used either alone or as an adjunct to stent retriever. This multicenter retrospective study reports angiographic data, complications, and clinical outcome in patients treated with aspiration thrombectomy as the first-line option. MATERIALS AND METHODS: We analysed the clinical and procedural data of patients treated from January 2014 to March 2015. Recanalization was assessed according to the Thrombolysis in Cerebral Infarction score. Clinical outcome was evaluated at discharge and after 3 months. RESULTS: Overall, 152 patients (mean age 68 years) were treated. Sites of occlusion were 90.8% anterior circulation (including 16.4% tandem extracranial/intracranial occlusions) and 9.2% basilar artery. In 79 patients administration of intravenous tissue plasminogen activator was attempted. Recanalization of the target vessel was obtained in 115/152 cases (75.6%) whereas direct aspiration alone was successful in 83/152 cases (54.6%) with an average puncture to revascularization time of 44.67 min. Symptomatic intracranial hemorrhage occurred in 7.8% and embolization to new territories in 1.9%. 77 patients (50.6%) had a good outcome at 90-day follow-up: 55/96 in the direct aspiration alone group and 22/56 in the aspiration-stent retriever group. CONCLUSIONS: Direct aspiration thrombectomy appears a feasible technique with good revascularization results achieved in more than half the patients. In light of the self-reported data, inhomogeneous patient selection, absence of a core imaging laboratory, and a non-standardized approach, the results should be validated in a larger trial.

Manual thromboaspiration technique as a first approach for endovascular stroke treatment: A single-center experience.

BACKGROUND: For intracranial large vessel occlusion in acute ischemic stroke (AIS), a high degree of revascularization in the minimal amount of time predicts good outcomes. Recently, different studies have shown that the direct aspiration first pass technique (ADAPT technique) for AIS obtains high recanalization rates, fast interventions and low costs when it works as first attempt. This study retrospectively describes revascularization efficacy, duration of procedure, intra and post-procedural complications, early and after 90-days clinical outcome in a group of patients who underwent ADAPT as the primary endovascular approach, eventually followed by stent retriever thrombectomy, for recanalization of large vessels in the anterior circulation. MATERIALS AND METHODS: We analyzed clinical and procedural data of patients treated from April 2014 to August 2015. Recanalization was assessed according to the Thrombolysis in Cerebral Infarction score. Clinical outcome was evaluated at discharge and after 3 months (modified Rankin Scale, mRS). RESULTS: Overall, 71 patients (mean age of 69.7 years) were treated. Sites of occlusion were anterior circulation (including seven tandem extracranial-intracranial occlusions). In 39 patients i.v. rtPA was attempted. Recanalization of the target vessel was obtained in 87.3% of cases whereas direct aspiration alone was successful in 46/71cases (64.8%) with an average puncture-to-revascularization time of 43.1 minutes. Symptomatic intracranial hemorrhage occurred in 7.8% and embolization to new territories in 5.6%. In total, 38 patients (53.5%) had a good outcome at 90 days follow-up. CONCLUSIONS: In our series, the manual thromboaspiration technique has been shown as fast and safe, with good rates of vessel revascularization in 87.3% of patients and neurological outcome <3 mRS in 53.5% of patients.

Hemodynamic and Anatomic Variations Require an Adaptable Approach during Intra-Arterial Chemotherapy for Intraocular Retinoblastoma: Alternative Routes, Strategies, and Follow-Up.

BACKGROUND AND PURPOSE: Intra-arterial chemotherapy for retinoblastoma is not always a straightforward procedure, and it may require an adaptable approach. This study illustrates strategies used when the ophthalmic artery is difficult to catheterize or not visible, and it ascertains the effectiveness and safety of these strategies. MATERIALS AND METHODS: A retrospective study was performed on a series of 108 eyes affected by intraocular retinoblastoma and selected for intra-arterial chemotherapy (follow-up range, 6-82 months). We recognized 3 different patterns of drug delivery: a fixed pattern through the ophthalmic artery, a fixed pattern through branches of the external carotid artery, and a variable pattern through either the ophthalmic or the external carotid artery. RESULTS: We performed 448 sessions of intra-arterial chemotherapy, 83.70% of them through the ophthalmic artery and 16.29% via the external carotid artery. In 24.52% of eyes, the procedure was performed at least once through branches of the external carotid artery. In 73 eyes, the pattern of drug delivery was fixed through the ophthalmic artery; for 9 eyes, it was fixed through branches of the external carotid artery; and for 17 eyes, the pattern was variable. Statistical analysis did not show any significant difference in the clinical outcome of the eyes (remission versus enucleation) treated with different patterns of drug delivery. Adverse events could not be correlated with any particular pattern. CONCLUSIONS: Alternative routes of intra-arterial chemotherapy for intraocular retinoblastoma appear in the short term as effective and safe as the traditional drug infusion through the ophthalmic artery.

Epidemic diffusion of KPC carbapenemase-producing Klebsiella pneumoniae in Italy: results of the first countrywide survey, 15 May to 30 June 2011.

Carbapenem-resistant Enterobacteriaceae (CRE) are emerging as a public health problem in various settings. In Italy, a rapid and remarkable increase of carbapenem-non-susceptible Klebsiella pneumoniae has been reported since 2010. Here we report on the results of a countrywide cross-sectional survey, carried out from 15 May to 30 June 2011 to investigate the diffusion of CRE in Italy and to characterise the most prevalent resistance mechanisms and their dissemination patterns. CRE were reported from most (23 of 25) participating laboratories, with an overall proportion of 3.5% and 0.3% among consecutive non-duplicate clinical isolates of Enterobacteriaceae from inpatients (n=7,154) and outpatients (n=6,595), respectively. K. pneumoniae was the most frequent species (proportion of carbapenem-non-susceptible isolates: 11.9%), while a minority of CRE of other species were detected. Carbapenemase production was detected in the majority (85%) of CRE. KPC-type enzymes were by far the most common (89.5% of carbapenemase producers), followed by VIM-1 (9.2%) and OXA-48 (1.3%). KPC-producing K. pneumoniae (KPC-KP) were detected in most centres and contributed majorly to the epidemic dissemination of CRE recently observed in our country. Dissemination of KPC-KP was mostly sustained by strains of clonal complex 258 (ST-258 producing KPC-2 or KPC-3, and ST-512 producing KPC-3), while a minority belonged to ST-101.

Reaction mechanisms in irradiated, precipitated, and mesoporous silica.

A matrix EPR spectroscopy study of the low temperature γ radiolysis of precipitated (Zeosil) and mesoporous high surface silica has afforded evidence of the formation of trapped H-atoms, H-atom centers, siloxy radicals ≡Si-O(•), anomalous silyl peroxy radicals ≡Si-OO(•) with reduced g tensor anisotropy, siloxy radical-cations (≡Si-O-Si≡)(+•), E' centers, and two species from Ge impurity. Coordination of peroxyl radicals with diamagnetic ≡Si(+) centers is proposed and tested by DFT computations in order to justify the observed g tensor. Coordination of H-atoms to ≡Si(+) centers is also proposed for the structure of the H-atom centers as an alternative model not requiring the intervention of Ge, Sn, or CO impurities. The DFT method has been employed to assess the electronic structure of siloxy radical-cations and its similarity with that of the carbon radical-cation analogues; the results have prompted a revision of the structures proposed in the literature for ST1 and ST2 centers. The comparison between the two types of silica has afforded evidence of different radiolysis mechanisms leading to a greater yield of trapped H-atoms and H-atom centers in zeosil silica, which is reckoned with the 4-fold greater concentration of silanol groups. Parallel radiolysis experiments carried out by using both types of silica with polybutadiene oligomers as adsorbate have afforded evidence of free valence and energy migration phenomena leading to irreversible linking of polybutadiene chains onto silica. Reaction mechanisms are proposed based on the detection of SiO2-bonded free radicals whose structure has been defined by EPR.

[Neuroimaging and definition of transient ischemic attack]. / Neuroimaging e definizione di attacco ischemico transitorio.

AIM: Transient ischemic attack (TIA) has to be considered an "alarm bell" of a more or less severe organic or systemic vasculopathy. Positive findings at neuroimaging means tissue damage. The purpose of this retrospective study was to assess the role of neuroimaging in the management of patients presenting with TIA, and to consider the relative implications. METHODS: In a consecutive series of 82 patients (53 males, 29 females, mean age: 65.9±13.1 years) admitted for TIA, it was possible to review the history and the clinical data of 66 patients, including ABCD2 score, laboratory including plasmatic D-dimer, and neuroimaging data including computed tomography (CT) and magnetic resonance imaging including diffusion-weighted with apparent diffusion coefficient measure (DWI-ADC) obtained at diagnosis and by a week later (16 by CT, and 50 by DWI-ADC). Thirty-three patients underwent DWI-ADC within 24 hours from symptoms onset. Statistical analysis has been performed by non-parametric tests (χ2 and Mann-Whitney), and logistic regression by a commercially available software. RESULTS: CT and/or DWI-ADC showed signs of acute ischemic lesions in 23/66 (35%) patients. 12 out of the 35 patients with a 24-hour DWI-ADC follow-up were positive. Statistical analysis showed that positive neuroimaging was significantly associated only with familial history of cardiovascular diseases (P<0.012) and previous TIA/stroke (P<0.046). CONCLUSION: In this patients series, at least 35% of patients with TIA had a positive neuroimaging, especially DWI-ADC. Positive neuroimaging seems an independent factor. Patients with TIA need an early assessment by neuroimaging including DWI-ADC, in order to obtain a correct classification and prognosis.

Influencia de factores socioeconómicos y culturales en la asociación entre índices de caries dental y la floruración del agua potable

El presente trabajo mide el impacto del agregado de flúor al agua potable en la reducción de caries dental en la población escolar de la localidad de Oberá. Misiones (Argentina) y evaluar la asociación entre los índices ceod y CPOD y variables cualitativas tales como el nivel socioeconómico, la higiene bucal y el acceso al agua potable florurada

Impacto de la floruración del agua potable en la prevalencia de caries y fluorosis dental en la población escolar del Municipio de Oberá Misiones Argentina

El trabajo analiza las condiciones socioeconómicas considerando que estas no provocan una situación diferencial (estadisticamente significativa) en materia de caries cuando son evaluados al paso del estrato de niveles socieconómico más alto a los más bajos, aumentan los porcentajes de niños sin experiencia odontológica, con caries que sangran y lo que es más importante se incrementan el porcentaje de escolares que presentan una higiene dental calificada como mala y de los que no tienen acceso al agua potable. Estos resultados plantean la necesidad de mejorar la cobertura de agua potable de atención odontológica en los sectores de menores ingresos e insistir en la realización de campaña de concientización que enfaticen la importancia de una buena higiene dental como medio que contribuye a prevenir las caries

Impacto de la floruración del agua potable en la prevalencia de caries y fluorosis dental en la población escolar del Municipio de Oberá Misiones Argentina

El trabajo analiza las condiciones socioeconómicas considerando que estas no provocan una situación diferencial (estadisticamente significativa) en materia de caries cuando son evaluados al paso del estrato de niveles socieconómico más alto a los más bajos, aumentan los porcentajes de niños sin experiencia odontológica, con caries que sangran y lo que es más importante se incrementan el porcentaje de escolares que presentan una higiene dental calificada como mala y de los que no tienen acceso al agua potable. Estos resultados plantean la necesidad de mejorar la cobertura de agua potable de atención odontológica en los sectores de menores ingresos e insistir en la realización de campaña de concientización que enfaticen la importancia de una buena higiene dental como medio que contribuye a prevenir las caries

Influencia de factores socioeconómicos y culturales en la asociación entre índices de caries dental y la floruración del agua potable

El presente trabajo mide el impacto del agregado de flúor al agua potable en la reducción de caries dental en la población escolar de la localidad de Oberá. Misiones (Argentina) y evaluar la asociación entre los índices ceod y CPOD y variables cualitativas tales como el nivel socioeconómico, la higiene bucal y el acceso al agua potable florurada

Endovascular treatment of a cavernous sinus dural arteriovenous fistula by transvenous embolisation through the superior ophthalmic vein via cannulation of a frontal vein.

We describe a new approach for transvenous embolisation of cavernous sinus dural arteriovenous fistulae through the superior ophthalmic vein (SOV), i.e., via percutaneous cannulation of a frontal vein. Modern neurointerventional angiographic materials make it possible to reach the SOV in this way without puncturing it in the orbit or a surgical exposure. Orbital phlebography should still be in the repertoire of interventional neuroradiology units in large centres.