Supported Gold Nanoparticles for Alcohols Oxidation in Continuous-Flow Heterogeneous Systems

Gold nanoparticles (AuNPs) were anchored on alkynyl carbamate-functionalized support materials having the suitable features for application as catalysts in continuous-flow packed bed reactors. The functionalization step was carried out by grafting with the di-functional organosilane [3-(2-propynylcarbamate)propyl]triethoxysilane (PPTEOS) three commercial micrometer-sized oxide supports, i.e. silica, alumina, and titania. The alkynyl-carbamate moieties were capable to straightforwardly reduce the gold precursor HAuCl4 yielding the supported AuNPs systems Au/SiO2@Yne, Au/Al2O3@Yne, and Au/TiO2@Yne. A comparison among the three materials revealed that silica allowed the highest organic functionalization (12 wt%) as well as the highest gold loading (3.7 wt%). Moreover, TEM investigation showed only for Au/SiO2@Yne the presence of homogeneously distributed, spherically shaped AuNPs (av. diameter 15 nm). Au/SiO2@Yne is an efficient catalyst, both in batch and flow conditions, in the oxidation of a large variety of alcohols, using H2O2 as oxidizing agent, at a temperature of 90 \ub0C. Furthermore, under flow conditions, the catalyst worked for over 50 h without any significant decrease in the catalytic activity. The catalytic activity of the three catalysts was evaluated and compared in the oxidation of 1-phenylethanol as a model substrate. We found that the flow approach plays a strategic role in preserving the physical and chemical integrity of the solid catalysts during its use, with remarkable consequences for the reaction conversion (from 2% in batch to 80 % in flow) in the case of Au/TiO2@Yne

Donor Cell Acute Myeloid Leukemia after Hematopoietic Stem Cell Transplantation for Chronic Granulomatous Disease: A Case Report and Literature Review

The patient reported here underwent hematopoietic stem cell transplantation (HSCT) due to chronic granulomatous disease (CGD) caused by biallelic mutations of the NCF1 gene. Two years later, he developed AML, which was unexpected and was recognized via sex-mismatched chromosomes as deriving from the donor cells; the patient was male, and the donor was his sister. Donor cell leukemia (DCL) is very rare, and it had never been reported in patients with CGD after HSCT. In the subsequent ten years, the AML relapsed three times and the patient underwent chemotherapy and three further HSCTs; donors were the same sister from the first HSCT, an unrelated donor, and his mother. The patient died during the third relapse. The DCL was characterized since onset by an acquired translocation between chromosomes 9 and 11, with a molecular rearrangement between the MLL and MLLT3 genes-a quite frequent cause of AML. In all of the relapses, the malignant clone had XX sex chromosomes and this rearrangement, thus indicating that it was always the original clone derived from the transplanted sister's cells. It exhibited the ability to remain quiescent in the BM during repeated chemotherapy courses, remission periods and HSCT. The leukemic clone then acquired different additional anomalies during the ten years of follow-up, with cytogenetic results characterized both by anomalies frequent in AML and by different, non-recurrent changes. This type of cytogenetic course is uncommon in AML

Sulfonates-PMMA nanoparticles conjugates: A versatile system for multimodal application

a b s t r a c t We report herein the viability of a novel nanoparticles (NPs) conjugated system, namely the attachment, based on ionic and hydrophobic interactions, of different sulfonated organic salts to positively charged poly(methylmethacrylate) (PMMA)-based core-shell nanoparticles (EA0) having an high density of ammonium groups on their shells. In this context three different applications of the sulfonates@EA0 systems have been described. In detail, their ability as cytotoxic drugs and pro-drugs carriers was evaluated in vitro on NCI-H460 cell line and in vivo against human ovarian carcinoma IGROV-1 cells. Besides, 8-hydroxypyrene-1,3,6-trisulfonic acid, trisodium salt (HPTS) was chosen for NPs loading, and its internalization as bioimaging probe was evaluated on Hep G2 cells. Overall, the available data support the interest for these PMMA NPs@sulfonates systems as a promising formulation for theranostic applications. In vivo biological data strongly support the potential value of these core-shell NPs as delivery system for negatively charged drugs or biologically active molecules. Additionally, we have demonstrated the ability of these PMMA core-shell nanoparticles to act as efficient carriers of fluorophores. In principle, thanks to the high PMMA NPs external charge density, sequential and very easy post-loading of different sulfonates is achievable, thus allowing the preparation of nanocarriers either with bi-modal drug delivery behaviour or as theranostic systems

Therapeutically targeting SELF-reinforcing leukemic niches in acute myeloid leukemia: A worthy endeavor?

A tight relationship between the acute myeloid leukemia (AML) population and the bone marrow (BM) microenvironment has been convincingly established. The AML clone contains leukemic stem cells (LSCs) that compete with normal hematopoietic stem cells (HSCs) for niche occupancy and remodel the niche; whereas, the BM microenvironment might promote AML development and progression not only through hypoxia and homing/adhesion molecules, but also through genetic defects. Although it is still unknown whether the niche influences treatment results or contains any potential target for treatment, this dynamic AML-niche interaction might be a promising therapeutic objective to significantly improve the AML cure rate. Am. J. Hematol. 91:507-517, 2016. (c) 2016 Wiley Periodicals, Inc

Indoor and outdoor volatile organic compounds monitoring in a multi-storey car park

A VOC monitoring was carried out inside and outside a multi-storey car park in order to characterize the emission profile of vehicular traffic source in an indoor environment. BTEX, and in particular toluene, were the most abundant compounds in all monitored sites, with different compositions between indoor parking areas and outdoor sites. The motor vehicle exhaust and gasoline vapor emission in these enclosed parking garages were characterized by diffusion or degradation phenomena different from those that occur in urban areas as the BTEX compositions, their ratios and their reactivity with OH and with NO3 radicals demonstrate. In detail, xylenes/BTEX and ethylbenzene/BTEX ratios in indoor environments were twice than those in outdoor ones, while toluene/BTEX ratio resulted half than that obtained in outdoor sites. In this work, BTEX concentrations depend both on number of vehicles, on vehicular characteristics (age, emission control technology, fuel quality etc.) and on factors related to the characteristics of parking facilities (volume of the monitored areas, indoor or open facilities, ventilation systems, size and maintenance). However, it was found that the external contribution (intrusion of pollutants from outdoor and from the other floors) and the influence of mixing air (removal of pollutants by ventilation and air exchange) on BTEX concentrations were not significant if inside the multi-storey car park there was a strong source (due to the number of vehicles) such happened in the first and second floors and along the ramp that connected them

Percutaneous coronary sinus catheterization with the ProPlege catheter under transesophageal echocardiography and pressure guidance

Objectives Percutaneous catheterization of the coronary sinus (CS) to enable the administration of retrograde cardioplegia may play an important role in minimally invasive cardiac surgery. A new specially designed device (ProPlege; Edwards Lifesciences, Irvine, CA) is described that can be placed under transesophageal echocardiography (TEE) and pressure guidance with a high rate of success and low rate of complications. Design Case series. Setting A university-affiliated private hospital. Participants Patients undergoing minimally invasive cardiac surgery. Interventions The ProPlege device was placed under TEE and pressure guidance only. Measurements and Main Results Records of 70 patients managed with ProPlege were reviewed and analyzed. Successful placement was attained in 69 patients (98.6%) as confirmed by the ventricularization of the CS pressure curve and TEE images. Direct imaging of the ProPlege tip was possible in 34 patients (49.2%). The capacity to generate a CS pressure>30 mmHg during retrograde cardioplegia administration at a flow>150 mL/min was obtained in 64 patients; ProPlege displacement occurred in 5 cases (7.2%). Successful retrograde cardioplegia was delivered in 91.4% of cases. No CS perforation or other injuries to the right heart were noted at intraoperative TEE or direct surgical inspection. Conclusions Percutaneous CS catheterization with ProPlege was performed with a high rate of success for positioning and low complication rate using TEE and pressure guidance only. Further studies are needed to more accurately determine complication rates and to establish the possible complementary role of fluoroscopy

Thiazolium-functionalized polystyrene monolithic microreactors for continuous-flow umpolung catalysis

Thiazolium salt pre-catalysts have been immobilized on silica and monolithic polystyrene and their activity was tested under batch conditions in three model umpolung reactions, namely the benzoin conden- sation of benzaldehyde, the acyloin-type condensation of biacetyl, and the Stetter reaction of biacetyl with trans-chalcone. A prerequisite of the study has been the utilization of environmentally benign water and ethanol solvents. After having established the higher performance of polystyrene monolithic thiazo- lium carbene catalysts, their effectiveness has been tested under the flow regime by fabricating the corresponding monolithic microreactors (pressure-resistant stainless-steel columns). Importantly, it has been demonstrated by a brief substrate scope study that the polymeric matrix and the continuous flow regime synergistically contribute to preserve the activity of the carbene catalysts over time, thus permit- ting the long-term operation (up to 7 days) of the prepared monolithic reactors for the production of valuable compounds via the umpolung strategy

Efficiency in CO2-utilization strategies: The case of styrene carbonate synthesis in microdroplets conditions

The styrene oxide to styrene carbonate conversion performed in CO2 atmosphere, herein selected as a case study, was implemented in microdroplets (aerosol) reactions at the preparative scale (3.5 mmol of the starting material) and mild conditions (1 atm CO2 pressure), within a custom-made ultrasonic nebulization reactor. Upon opti- mization of the promoter stoichiometry (1 eq of 4.3 TEG/KI ratio) and methanol (MeOH) dilution (7.5 mL of 2.5 v/v MeOH/TEG), performances under mass transfer-limited conditions of this novel methodological paradigm have been compared at 25 ◦C and 50 ◦C with those implemented as: a) no-stirred, b) stirred, and c) sonicated bulk reactions. Complete selectivity and an apparent acceleration factor (AAF) of 1.9 was registered at both temperature for microdroplets reactions in respect with the sonicated counterparts, these latter performing better than the other bulk reactions. These significative efficiency improvements, candidate aerosol reactions as a preferred process intensification approach in the realm of effective CO2-utilization strategies and, in general, in the development and exploitation of gas-liquid two-phase reactions

TPPS supported on core–shell PMMA nanoparticles: the development of continuous- flow membrane-mediated electrocoagulation as a photocatalyst processing method in aqueous media

Herein, the successful utilization of core shell poly-methyl methacrylate nanoparticles (CS-PMMA NPs) as a valuable support for organocatalyst immobilization in aqueous medium is presented along with an unprecedented direct current-based electrochemical method for processing a water colloid of the result- ing nano-supported catalyst. The NP coagulation procedure relied on various electrocoagulation tech- niques and it was achieved through water electrolysis occurring in a dialysis membrane immersed in the colloid. Mass recoveries of up to 95% w/w were obtained for the NPs within 1 h of electrolysis. This was optimized at a constant current of 90 mA or a constant potential of 24 V. The disclosed NP separation procedure was effectively exploited in a continuous-flow reaction/separation/recycle sequence involving the tetraphenylporphyrin tetrasulfonate (TPPS) organo-photocatalyst immobilized on CS-PMMA NPs (NP2s). After an optimization study aimed at maximizing the chemical efficiency of the entire synthetic and purification process, the nano-supported catalyst NP2 (0.05 mol%) efficiently promoted the photo- excitation of triplet oxygen to singlet oxygen for the selective and environmentally benign sulfoxidation of a model sulfide in an aqueous medium