Reconfigurable Carbon Nanotube Multiplexed Sensing Devices

Here we report on the fabrication of reconfigurable and solution processable nanoscale biosensors with multisensing capability, based on single-walled carbon nanotubes (SWCNTs). Distinct DNA-wrapped (hence water-soluble) CNTs were immobilized from solution onto different prepatterned electrodes on the same chip, via a low-cost dielectrophoresis (DEP) methodology. The CNTs were functionalized with specific, and different, aptamer sequences that were employed as selective recognition elements for biomarkers indicative of stress and neuro-trauma conditions. Multiplexed detection of three different biomarkers was successfully performed, and real-time detection was achieved in serum down to physiologically relevant concentrations of 50 nM, 10 nM, and 500 pM for cortisol, dehydroepiandrosterone-sulfate (DHEAS), and neuropeptide Y (NPY), respectively. Additionally, the fabricated nanoscale devices were shown to be reconfigurable and reusable via a simple cleaning procedure. The general applicability of the strategy presented, and the facile device fabrication from aqueous solution, hold great potential for the development of the next generation of low power consumption portable diagnostic assays for the simultaneous monitoring of different health parameters.

Attenuated Glial Reactivity on Topographically Functionalized Poly(3,4-Ethylenedioxythiophene):P-Toluene Sulfonate (PEDOT:PTS) Neuroelectrodes Fabricated by Microimprint Lithography

Following implantation, neuroelectrode functionality is susceptible to deterioration via reactive host cell response and glial scar-induced encapsulation. Within the neuroengineering community, there is a consensus that the induction of selective adhesion and regulated cellular interaction at the tissue-electrode interface can significantly enhance device interfacing and functionality in vivo. In particular, topographical modification holds promise for the development of functionalized neural interfaces to mediate initial cell adhesion and the subsequent evolution of gliosis, minimizing the onset of a proinflammatory glial phenotype, to provide long-term stability. Herein, a low-temperature microimprint-lithography technique for the development of micro-topographically functionalized neuroelectrode interfaces in electrodeposited poly(3,4-ethylenedioxythiophene):p-toluene sulfonate (PEDOT:PTS) is described and assessed in vitro. Platinum (Pt) microelectrodes are subjected to electrodeposition of a PEDOT:PTS microcoating, which is subsequently topographically functionalized with an ordered array of micropits, inducing a significant reduction in electrode electrical impedance and an increase in charge storage capacity. Furthermore, topographically functionalized electrodes reduce the adhesion of reactive astrocytes in vitro, evident from morphological changes in cell area, focal adhesion formation, and the synthesis of proinflammatory cytokines and chemokine factors. This study contributes to the understanding of gliosis in complex primary mixed cell cultures, and describes the role of micro-topographically modified neural interfaces in the development of stable microelectrode interfaces.

Fulminant Hepatic Failure Caused by Diffuse Intrasinusoidal Metastatic Liver Disease: A Case Report

A 53-year-old woman experienced rapidly progressing liver failure four years after a quadrantectomy for a breast carcinoma. She had received adjuvant chemotherapy and radiotherapy, and second-line chemotherapy for bone metastasis one year earlier. The hepatic failure manifested with ascites, jaundice, elevation of serum bilirubin and hepatic enzyme levels and hypoalbuminemia. Imaging studies showed an enlarged liver without metastatic lesions. The patient died of hepatic decompensation within two weeks. Liver examination at autopsy revealed massive neoplastic infiltration consistent with a primary breast carcinoma. It is important to realize that this unusual pattern of liver metastasis cannot be demonstrated even with the most advanced techniques of instrumental diagnosis (CT scan, ultrasonography and magnetic resonance imaging), and should be taken into account in the differential diagnosis of rapidly progressing liver failure.

Efficacy and safety of boosted darunavir-based antiretroviral therapy in HIV-1-positive patients: results from a meta-analysis of clinical trials

Darunavir/ritonavir (DRV/r) is a second-generation protease inhibitor used in treatment-naïve and -experienced HIV-positive adult patients. To evaluate efficacy and safety in these patient settings, we performed a meta-analysis of randomized controlled trials. We considered eight studies involving 4240 antiretroviral treatment (ART)-naïve patients and 14 studies involving 2684 ART-experienced patients. Regarding efficacy in the ART-naive patients, the virological response rate was not significantly different between DRV/r and the comparator. For the ART-experienced failing patients, the virological response rate was significantly higher with DRV/r than with the comparator (RR 1.45, 95% CI: 1.01-2.08); conversely, no significant differences were found between the treatment-experienced and virologically controlled DRV/r and comparator groups. Regarding safety, the discontinuation rates due to adverse events (AEs) and DRV/r-related serious adverse events (SAEs) did not significantly differ from the rates in the comparator group (RR 0.84, 95% CI: 0.59-1.19 and RR 0.78, 95% CI: 0.57-1.05, respectively). Our meta-analysis indicated that DRV/r-based regimens were effective and tolerable for both types of patients, which was consistent with published data.

Synthesis of (±)-3,4-dimethoxybenzyl-4-methyloctanoate as a novel internal standard for capsinoid determination by HPLC-ESI-MS/MS(QTOF)

Capsinoids exhibit health-promoting properties and are therefore compounds of interest for medical and food sciences. They are minor compounds present in relatively high concentrations in only a few number of pepper cultivars. It is desirable to quantify capsinoids to provide selected cultivars with high capsinoid contents, which can then be employed as health food product. Quantifying low concentrations of capsinoids from pepper fruit requires a precise and selective analytical technique such as HPLC coupled to electrospray ionization - mass spectrometry, with development of an internal standard essential. In this work, the synthesis method of a novel compound analogue of capsinoids, the (±)-3,4-dimethoxybenzyl-4-methyloctanoate, which could be a suitable internal standard for capsinoid determination by electrospray ionization - mass spectrometry is described.

(±)-3,4-dimethoxybenzyl-4-methyloctanoate was stable under the analysis conditions and exerted chemical and physical properties similar to those of capsinoids. This internal standard will provide an accurate capsinoid determination by electrospray ionization - mass spectrometry, thus facilitating the pepper breeding programs, screening pepper cultivars and a better understanding of capsinoid biosynthetic pathway.

Single-Molecule Patterning via DNA Nanostructure Assembly: A Reusable Platform

Here we describe a facile strategy of general applicability for controlling the immobilization of individual nanomoieties on nanopatterned surfaces with single-molecule control. We combine the ability of DNA nanostructures as programmable platforms, with a one-step Focused Ion Beam nanopatterning, to demonstrate the controlled immobilization of DNA origami functionalized with individual quantum dots (QDs) at predesigned positions on glass coverslips and silicon substrates. Remarkably, the platform developed is reusable after a simple cleaning process, and can be designed to display different geometrical arrangements.

Site-Specific One-to-One Click Coupling of Single Proteins to Individual Carbon Nanotubes: A Single-Molecule Approach

We report the site-specific coupling of single proteins to individual carbon nanotubes (CNTs) in solution and with single-molecule control. Using an orthogonal Click reaction, Green Fluorescent Protein (GFP) was engineered to contain a genetically encoded azide group and then bound to CNT ends in different configurations: in close proximity or at longer distances from the GFP's functional center. Atomic force microscopy and fluorescence analysis in solution and on surfaces at the single-protein level confirmed the importance of bioengineering optimal protein attachment sites to achieve direct protein-nanotube communication and bridging.

The Functional Response of Mesenchymal Stem Cells to Electron-Beam Patterned Elastomeric Surfaces Presenting Micrometer to Nanoscale Heterogeneous Rigidity

Cells directly probe and respond to the physicomechanical properties of their extracellular environment, a dynamic process which has been shown to play a key role in regulating both cellular adhesive processes and differential cellular function. Recent studies indicate that stem cells show lineage-specific differentiation when cultured on substrates approximating the stiffness profiles of specific tissues. Although tissues are associated with a range of Young's modulus values for bulk rigidity, at the subcellular level, tissues are comprised of heterogeneous distributions of rigidity. Lithographic processes have been widely explored in cell biology for the generation of analytical substrates to probe cellular physicomechanical responses. In this work, it is shown for the first time that that direct-write e-beam exposure can significantly alter the rigidity of elastomeric poly(dimethylsiloxane) substrates and a new class of 2D elastomeric substrates with controlled patterned rigidity ranging from the micrometer to the nanoscale is described. The mechanoresponse of human mesenchymal stem cells to e-beam patterned substrates was subsequently probed in vitro and significant modulation of focal adhesion formation and osteochondral lineage commitment was observed as a function of both feature diameter and rigidity, establishing the groundwork for a new generation of biomimetic material interfaces.

Carbon Nanotube-Quantum Dot Nanohybrids: Coupling with Single-Particle Control in Aqueous Solution

A strategy is reported for the controlled assembly of organic-inorganic heterostructures consisting of individual single-walled carbon nanotubes (SWCNTs) selectively coupled to single semiconductor quantum dots (QDs). The assembly in aqueous solution was controlled towards the formation of monofunctionalized SWCNT-QD structures. Photoluminescence studies in solution, and on surfaces at the single nanohybrid level, showed evidence of electronic coupling between the two nanostructures. The ability to covalently couple heterostructures with single particle control is crucial for the design of novel QD-based optoelectronic and light-energy conversion devices.

Magnetic cooling for microkelvin nanoelectronics on a cryofree platform

We present a parallel network of 16 demagnetization refrigerators mounted on a cryofree dilution refrigerator aimed to cool nanoelectronic devices to sub-millikelvin temperatures. To measure the refrigerator temperature, the thermal motion of electrons in a Ag wire-thermalized by a spot-weld to one of the Cu nuclear refrigerators-is inductively picked-up by a superconducting gradiometer and amplified by a SQUID mounted at 4 K. The noise thermometer as well as other thermometers are used to characterize the performance of the system, finding magnetic field independent heat-leaks of a few nW/mol, cold times of several days below 1 mK, and a lowest temperature of 150 μK of one of the nuclear stages in a final field of 80 mT, close to the intrinsic SQUID noise of about 100 μK. A simple thermal model of the system capturing the nuclear refrigerator, heat leaks, and thermal and Korringa links describes the main features very well, including rather high refrigerator efficiencies typically above 80%.

DNA-Mediated Patterning of Single Quantum Dot Nanoarrays: A Reusable Platform for Single-Molecule Control

We present a facile strategy of general applicability for the assembly of individual nanoscale moieties in array configurations with single-molecule control. Combining the programming ability of DNA as a scaffolding material with a one-step lithographic process, we demonstrate the patterning of single quantum dots (QDs) at predefined locations on silicon and transparent glass surfaces: as proof of concept, clusters of either one, two, or three QDs were assembled in highly uniform arrays with a 60 nm interdot spacing within each cluster. Notably, the platform developed is reusable after a simple cleaning process and can be designed to exhibit different geometrical arrangements.

Epilessia parziale e risonanza magnetica

Sono stati esaminati con apparecchio a risonanza magnetica a media intensità di campo (0,5 T) 33 pazienti con epilessia parziale complessa. Tutti i pazienti presentavano un buon controllo delle crisi con terapia medica. I risultati ottenuti possono essere suddivisi in quattro gruppi: a) 13 pazienti con reperti RM negativi; b) 14 pazienti con reperti RM positivi per lesioni strutturali; c) 4 pazienti con reperti RM di segni indiretti di sofferenza parenchimale del lobo temporale e d) 2 pazienti con reperti RM di sclerosi mesiale del lobo temporale. Tali risultati sono in accordo con quelli riportati in letteratura; solo le percentuali di positività per sclerosi mesiale del lobo temporale sono discordanti. Ciò potrebbe dipendere da una diversa selezione dei pazienti (pazienti con crisi controllate o resistenti alla terapia medica) e dalla severità della sclerosi mesiale. L'interpretazione etiopatogenetica della sclerosi mesiale e le sue correlazioni cliniche sono ancora controverse e necessitano di ulteriori studi longitudinali.

La risonanza magnetica del feto

La RM fetale si candida come metodica di approfondimento nella diagnostica per immagini prenatale, dopo il classico approccio ecografico entrato ormai nel depistage di massa delle anomalie fetali. Il ricorso alla RM fetale ha una storia breve ma l'interesse dei vari autori a questa metodica è risultato crescente nell'ultimo decennio.

In questo lavoro viene presentata una breve revisione critica dei dati della letteratura con alcune annotazioni sulle diverse soluzioni tecniche proposte. Viene soprattutto discusso il problema legato ai movimenti fetali che tendono a degradare l'immagine RM dando particolare risalto alle manovre eco-guidate di curarizzazione fetale. Vengono quindi riportati i risultati su una casistica di 27 pazienti gravide in epoca gestazionale compresa tra il secondo ed il terzo trimestre, 22 delle quali sottoposte a curarizzazione fetale. In particolare sono presentati i diversi risultati RM in relazione al diverso dosaggio e al diverso agente curaro-simile impiegato e alcuni dettagli tecnici sull'esecuzione della RM fetale. In questa prima parte del nostro lavoro viene infine discussa l'anatomia normale del cervello fetale all'RM.

La risonanza magnetica del feto

Vengono riportati i quadri patologici osservati in 27 RM fetali prenatali e catalogati in sezioni.

Nella sezione riguardante l'anencefalia e la microcefalia sono discussi rispettivamente un caso di anencefalia classica, una microcefalia vera di Evrard, una microcefalia semplice associata a malformazioni in altri apparati ed una rara osservazione di iniencefalia. Nella sezione delle oloprosencefalie sono riportate due oloprosencefalie alobari e due oloprosencefalie semilobari. Nella sezione della agenesia del corpo calloso, sono illustrati 5 casi di agenesia totale, 2 casi isolati, e 3 associati ad altre anomalie del sistema nervoso. Una cisti in tensione del setto pellucido è stata arbitrariamente inserita in quest'ultima sezione.

Fra i complessi di Dandy-Walker sono enumerate una malformazione classica di Dandy-Walker, 2 Dandy-Walker variant ed una megacisterna magna.

Le anomalie di Chiari riscontrate sono state 2 e si riferiscono entrambe ad una condizione a tipo Chiari I, associata ad idrocefalo in un caso, ad agenesia del corpo calloso nell'altro. In un ultima sezione vengono presentati 2 casi di moderata idrocefalia e due casi di cospicua idrocefalia. Vengono infine presentate alcune brevi considerazioni conclusive sulla validità della metodica.

Responsive Biomaterials: Advances in Materials Based on Shape-Memory Polymers

Shape-memory polymers (SMPs) are morphologically responsive materials with potential for a variety of biomedical applications, particularly as devices for minimally invasive surgery and the delivery of therapeutics and cells for tissue engineering. A brief introduction to SMPs is followed by a discussion of the current progress toward the development of SMP-based biomaterials for clinically relevant biomedical applications.

Solution-Processable Carbon Nanoelectrodes for Single-Molecule Investigations

Here we present a solution-based assembly method for producing molecular transport junctions employing metallic single-walled carbon nanotubes as nanoelectrodes. The molecular junction conductance of a series of oligophenyls was successfully measured, highlighting the potential of an all-carbon based approach for the fabrication of solution-processable single-molecule junctions for molecular electronics.

Directed Assembly of Single Wall Carbon Nanotube Field Effect Transistors

The outstanding electronic properties of single wall carbon nanotubes (SWCNTs) have made them prime candidates for future nanoelectronics technologies. One of the main obstacles to the implementation of advanced SWCNT electronics to date is the inability to arrange them in a manner suitable for complex circuits. Directed assembly of SWCNT segments onto lithographically patterned and chemically functionalized substrates is a promising way to organize SWCNTs in topologies that are amenable to integration for advanced applications, but the placement and orientational control required have not yet been demonstrated. We have developed a technique for assembling length sorted and chirality monodisperse DNA-wrapped SWCNT segments on hydrophilic lines patterned on a passivated oxidized silicon substrate. Placement of individual SWCNT segments at predetermined locations was achieved with nanometer accuracy. Three terminal electronic devices, consisting of a single SWCNT segment placed either beneath or on top of metallic source/drain electrodes were fabricated. Devices made with semiconducting nanotubes behaved as typical p-type field effect transistors (FETs), whereas devices made with metallic nanotubes had a finite resistance with little or no gate modulation. This scalable, high resolution approach represents an important step forward toward the potential implementation of complex SWCNT devices and circuits.

Advances in Functional Assemblies for Regenerative Medicine

The ability to synthesise bioresponsive systems and selectively active biochemistries using polymer-based materials with supramolecular features has led to a surge in research interest directed towards their development as next generation biomaterials for drug delivery, medical device design and tissue engineering.

Targets for Ibrutinib Beyond B Cell Malignancies

Ibrutinib (Imbruvica^™) is an irreversible, potent inhibitor of Bruton's tyrosine kinase (BTK). Over the last few years, ibrutinib has developed from a promising drug candidate to being approved by FDA for the treatment of three B cell malignancies, a truly remarkable feat. Few, if any medicines are monospecific and ibrutinib is no exception; already during ibrutinib's initial characterization, it was found that it could bind also to other kinases. In this review, we discuss the implications of such interactions, which go beyond the selective effect on BTK in B cell malignancies. In certain cases, the outcome of ibrutinib treatment likely results from the combined inhibition of BTK and other kinases, causing additive or synergistic, effects. Conversely, there are also examples when the clinical outcome seems unrelated to inhibition of BTK. Thus, more specifically, adverse effects such as enhanced bleeding or arrhythmias could potentially be explained by different interactions. We also predict that during long‐term treatment bone homoeostasis might be affected due to the inhibition of osteoclasts. Moreover, the binding of ibrutinib to molecular targets other than BTK or effects on cells other than B cell‐derived malignancies could be beneficial and result in new indications for clinical applications.

Directed Assembly of End-Functionalized Single Wall Carbon Nanotube Segments

A key impediment to the implementation of a nanoelectronics technology based on single wall carbon nanotubes (SWCNTs) is the inability to arrange them in a manner suitable for integration into complex circuits. As a step toward addressing this problem, we explore the binding of fixed-length, end-functionalized SWCNT segments to lithographically defined nanoscale anchors, such that individual SWCNTs can be placed with control over position and orientation. Both monovalent and bivalent bindings are explored using covalent and noncovalent binding chemistries. Placement efficiency is assessed in terms of overall yield of SWCNT binding, as well as binding specificity and the degree of nonspecific binding. Placement yields as high as 93% and 79% are achieved, respectively, for covalent binding and for binding through DNA hybridization. Orientational control of the SWCNT segments is achieved with 95% and 51% efficiency for monovalent and bivalent bindings, respectively. This represents a new approach that could pave the way toward complex SWCNT devices and circuits.