Ionothermal synthesis of calcium-based metal–organic frameworks in a deep eutectic solvent

The ionothermal synthesis of Ca-MOFs has been performed using the 1 : 2 choline chloride : e-urea deep eutectic solvent, allowing the preparation of water sensitive materials.

MOF side chains as sources of supramolecular interactions: organic pollutant extraction from water

Supramolecular functionalization of MOFs (SUM-103): application to the extraction of pollutants from water.

CO2 Capture by Hydroxylated Azine-Based Covalent Organic Frameworks

Covalent organic frameworks (COFs) RIO-13, RIO-12, RIO-11, and RIO-11m were investigated towards their CO₂ capture properties by thermogravimetric analysis at 1 atm and 40 °C. These microporous COFs bear in common the azine backbone composed of hydroxy-benzene moieties but differ in the relative number of hydroxyl groups present in each material. Thus, their sorption capacities were studied as a function of their textural and chemical properties. Their maximum CO₂ uptake values showed a strong correlation with an increasing specific surface area, but that property alone could not fully explain the CO₂ uptake data. Hence, the specific CO₂ uptake, combined with DFT calculations, indicated that the relative number of hydroxyl groups in the COF backbone acts as an adsorption threshold, as the hydroxyl groups were indeed identified as relevant adsorption sites in all the studied COFs. Additionally, the best performing COF was thoroughly investigated, experimentally and theoretically, for its CO₂ capture properties in a variety of CO₂ concentrations and temperatures, and showed excellent isothermal recyclability up to 3 cycles.

HKUST-1 MOF in reline deep eutectic solvent: synthesis and phase transformation

The fate of HKUST-1 (Cu₃(BTC)₂, BTC = 1,3,5-benzenetricarboxylate) in the green Deep Eutectic Solvent (DES) reline (choline chloride/urea 1 : 2) was investigated, highlighting that not only reline can be used to make this MOF but also to transform it into another crystalline material. The synthesis of HKUST-1(reline) showing good textural properties and a particular rose morphology was indeed successfully achieved in this solvent. However, upon optimizing the reaction conditions such as concentration and metal/ligand ratio, it was found that another structure Cu₂(BTC)Cl also forms. It was unequivocally demonstrated that, upon heating in reline, HKUST-1 converts to the non-porous chloride-incorporating material. Hence, a novel feature of DES in MOF synthesis is uncovered: its role as a structure-directing agent, triggering the transformation between two different MOF structures.

CO2 adsorption mechanisms on MOFs: a case study of open metal sites, ultra-microporosity and flexible framework

In this review the CO₂ adsorption mechanisms of MOF-74-Mg, HKUST-1, SIFSIX-3-M, and ZIF-8 are explored, highlighting their preferential adsorption sites, CO₂–MOF complex configuration, adsorption dynamics, bonding angle, and water stability.

Improving the colonization and functions of Wharton's Jelly-derived mesenchymal stem cells by a synergetic combination of porous polyurethane scaffold with an albumin-derived hydrogel

The development of neo-tissues assisted by artificial scaffolds is continually progressing, but the reproduction of the extracellular environment surrounding cells is quite complex. While synthetic scaffolds can support cell growth, they lack biochemical cues that can prompt cell proliferation or differentiation. In this study, Wharton's Jelly-derived mesenchymal stem cells are seeded on a polyurethane (PU) scaffold combined with a hydrogel based on bovine serum albumin (BSA). BSA hydrogel is obtained through thermal treatment. While such treatment leads to partial unfolding of the protein, we show that the extent of denaturation is small enough to maintain its bioactivity, such as protein binding. Therefore, BSA provides a suitable playground for cells inside the scaffold, allowing higher spreading, proliferation and matrix secretions. Furthermore, the poor mechanical properties of the hydrogel are compensated for by the porous PU scaffold, whose architecture is well controlled. We show that even though PU by itself can allow cell adhesion and protein secretion, cell proliferation is 3.5 times higher in the PU + BSA scaffolds as compared to pure PU after 21 d, along with the non-collagenous protein secretions (389 versus 134 μmmg ^-1). Conversely, the secretion of sulphated glycosaminoglycans is 12.3-fold higher in the scaffold made solely of PU. Thereby, we propose a simple approach to generating a hybrid material composed of a combination of PU and BSA hydrogel as a promising scaffold for tissue regeneration.

Comparison of pleural and esophageal pressure in supine and prone positions in a porcine model of acute respiratory distress syndrome

Patients with moderate to severe acute respiratory distress syndrome (ARDS) benefit from prone positioning. Although the accuracy of esophageal pressure (Pes) to estimate regional pleural pressure (Ppl) has previously been assessed in the supine position, such data are not available in the prone position in ARDS. In six anesthetized, paralyzed, and mechanically ventilated female pigs, we measured Pes and Ppl into dorsal and ventral parts of the right pleural cavity. Airway pressure (Paw) and flow were measured at the airway opening. Severe ARDS [arterial partial pressure of oxygen ([Formula: see text])/fraction of inspired oxygen ([Formula: see text]) < 100 mmHg at positive end-expiratory pressure (PEEP) of 5 cmH₂O] was induced by surfactant depletion. In supine and prone positions assigned in a random order, PEEP was set to 20, 15, 10, and 5 cmH₂O and static end-expiratory chest wall pressures were measured from Pes (PEEPtot,es) and dorsal (PEEPtot,PplD) and ventral (PEEPtot,PplV) Ppl. The magnitude of the difference between PEEPtot,es and PEEPtot,PplD was similar in each position [-3.6 cmH₂O in supine vs. -3.8 cmH₂O in prone at PEEP 20 cmH₂O (PEEP 20)]. The difference between PEEPtot,es and PEEPtot,PplV became narrower in the prone position (-8.3 cmH₂O supine vs. -3.0 cmH₂O prone at PEEP 20). PEEPtot,PplV was overestimated by Pes in the prone position at higher pressures. The median (1st-3rd quartiles) dorsal-to-ventral Ppl gradient was 4.4 (2.4-6.8) cmH₂O in the supine position and -1.5 (-3.5 to +1.1) cmH₂O in the prone position (P < 0.0001) and marginally influenced by PEEP (P = 0.058). Prone position narrowed end-expiratory dorsal-to-ventral Ppl vertical gradient, likely because of a more even distribution of mechanical forces over the chest wall.NEW & NOTEWORTHY In a porcine model of acute respiratory distress syndrome, we found that static end-expiratory esophageal pressure did not change significantly in prone position compared with supine position at any positive end-expiratory pressure (PEEP) tested between 5 and 20 cmH₂O. Prone position was associated with an increased ventral pleural pressure and reduced end-expiratory dorsal-to-ventral pleural pressure (Ppl) vertical gradient, likely due to a more even distribution of mechanical forces over the chest wall.

PFG-NMR as a Tool for Determining Self-Diffusivities of Various Probe Molecules through H-ZSM-5 Zeolites

The understanding of major zeolite applications is partially based on diffusion of molecules inside or outside microporous networks. However, it is still a challenge to measure such phenomena. The diffusion ordered nuclear magnetic resonance spectroscopy (DOSY) technique has been reported to measure a probe molecule's diffusion inside porous solids. Pulsed-field gradient (PFG)-NMR has been used herein to measure the self-diffusivity of different probe molecules, such as neopentane, benzene, toluene and 1-dodecene with increasing dynamic diameter, respectively, on a series of H-ZSM-5 zeolites. The latter materials exhibit different crystal sizes, Si/Al ratios and the presence (or absence) of crystalline defects. In addition, shaped zeolite bodies representing industrial catalysts were compared with the afore-mentioned samples.

CO2 Adsorption Capacities in Zeolites and Layered Double Hydroxide Materials

The development of technologies that allow us to reduce CO₂ emissions is mandatory in today's society. In this regard, we present herein a comparative study of CO₂ adsorption over three types of materials: zeolites, layered double hydroxides (LDH), and zeolites coated LDH composites. The influence of the zeolite Si/Al ratio on zeolites sorption capacity along with the presence of mesopores was investigated. By comparing these results with the well-known performance of LDHs, we aim to provide insights on the factors that may influence the CO₂ capture capacity over zeolites, thus providing useful tools for tuning their properties upon post-treatments.

Biomass-mediated ZSM-5 zeolite synthesis: when self-assembly allows to cross the Si/Al lower limit

A family of Al-rich ZSM-5 zeolites with Si/Al = 8 ± 0.5 was prepared according to a biomass-mediated supramolecular approach. A combination of advanced characterisation techniques and periodic density functional theory (DFT) calculations unraveled the purity and stability of un-expected Al-enriched ZSM-5 structures, hence allowing to cross the frontier of Si/Al lower limit. In addition, these Al-rich ZSM-5 zeolites demonstrated high catalytic activity in n-hexane cracking and methanol conversion into hydrocarbons, being in line with the presence of numerous Brønsted acid sites.

Hydroxylation of Phenol over M-MCM-48

<p>The synthesis and characterization of M-MCM-48 (M= Si, Ti, V, Cr and Mn) materials have been carried out. These systems promote hydroxylation of phenol with 30 % H₂O₂ and the hydroxylation activity is highest for Ti-MCM-48. Water appears to be a better solvent than acetone and acetonitrile.</p>

One-step synthesis of a highly homogeneous SBA-NHC hybrid material: en route to single-site NHC-metal heterogeneous catalysts with high loadings

The one-step synthesis of a mesoporous silica of SBA type, functionalized with a 1-(2,6-diisopropylphenyl)-3-propyl-imidazolium (iPr2Ar-NHC-propyl) cation located in the pore channels, is described. This material was obtained by the direct hydrolysis and co-condensation of tetraethylorthosilicate (TEOS) and 1-(2,6-diisopropylphenyl)-3-[3-(triethoxysilyl)propyl]-imidazolium iodide in the presence of Pluronic P123 as a non-ionic structure-directing agent and aqueous HCl (37%) as an acid catalyst. Small-angle X-ray diffraction measurements, scanning and transmission electron microscopies, as well as dinitrogen sorption analyses revealed that the synthesized material is highly mesoporous with a 2D hexagonal arrangement of the porous network. (13)C and (29)Si CP-MAS NMR spectroscopy confirmed that the material contains intact iPr2Ar-NHC-propyl cations, which are covalently anchored via silicon atoms fused into the silica matrix. Moreover, comparison of the latter data with those of an analogous post-synthetic grafted SBA-NHC material allowed us to establish that, as expected, (i) it is most probably more homogeneous and (ii) it shows a more robust anchoring of the organic units. Finally, elemental mapping by energy dispersive X-ray spectroscopy in the scanning electron microscope demonstrated a very homogeneous distribution of the imidazolium units within the one-pot material, moreover with a high content. This study thus demonstrates that a relatively bulky and hydrophilic imidazolium unit can be directly co-condensed with TEOS in the presence of a structure-directing agent to provide in a single step a highly ordered and homogeneous mesoporous hybrid SBA-NHC material, possessing a significant number of cationic NHC sites.

Pregnancy is associated with a decrease in pharyngeal but not tracheal or laryngeal cross-sectional area: a pilot study using the acoustic reflection method

BACKGROUND

The risk of difficult upper airway access is increased during pregnancy, especially in labor. Changes in upper airway calibre have been poorly studied during pregnancy. The acoustic reflection method is a non-invasive technique that allows a longitudinal assessment of the cross-sectional area of the upper airway from the mouth to carina. We used this technique to evaluate upper airway calibre during normal pregnancy.

METHODS

We conducted a prospective, single centre, observational study with a clinical and upper airway acoustic reflection method evaluation of healthy women during the first, second and third trimesters of pregnancy, and up to two days and one month after delivery.

RESULTS

Fifty women participated to the study. The mean pharyngeal cross-sectional area decreased between the first and third trimesters (P < 0.001) with no significant change of the minimal and mean tracheal cross-sectional areas. The Mallampati score increased during pregnancy between the first and third trimesters (P< 0.001).

CONCLUSION

Using measurements with the acoustic reflection method, normal pregnancy is associated with a significant reduction in the cross-sectional area of the pharynx and a concomitant increase in the Mallampati score. No change was observed in the minimal and mean tracheal cross-sectional areas.

Abstract P5-21-01: pT1a, bpN0M0 breast cancer: clinicopathological characteristics and their impact on treatment decision. Central review of the prospective ODISSEE cohort

Background: The incidence of infra-centimetric breast cancer (BC) is increasing due to mass screening. The management remains controversial opposing locoregional treatment only based on low stage and potentially aggressive tumor biology (especially for triple negative and HER2 positive tumors). The objectives of the prospective multicenter ODISSEE study were i) to describe daily practice management of pT1ab BC, ii) to identify potential new biomarkers and iii) to describe long term outcome (10-year follow up).

Methods: 616 patients with unifocal pT1a, b pN0M0 BC were included after surgery from May 2009 to March 2010 in 116 centers. Paraffin blocks were available for central pathology review in 350 patients. Due to the small tumor size, tissue microarray (TMA) construction was finally achieved for 287 cases. Collection of additional tumor blocks is ongoing. Review of the cases was performed independently by two pathologists and discordant cases were reviewed under a multihead microscope. Histological characteristics (histological type, tumor size and grade, presence of in situ component, presence of lymphovascular invasion) were assessed on whole tissue sections. Immunohistochemical detection of ER, PR, HER2, Ki67, EGFR, cytokeratin 5/6, Bcl-2 was performed on TMAs.

Results: Clinicopathological characteristics of the 287 centrally reviewed cases were similar to those of the 616 patients included in the cohort. Median age: 60.1 years (range [31–89] years). Median tumor size: 7.8 mm (range [1–10] mm) with 11% pT1a and 89% pT1b. Histological types: 72% ductal, 11% lobular and 17% other types (among which 53% of tubular). Minor in situ component was found in 36% of the cases, and invasive carcinoma with an extensive in situ component in 1.9%. Most of tumors were histological grade I and II (52% and 40% respectively), 8% were grade III. Proliferation was low as assessed by mitotic count (low 82%, intermediate 13% and high 5%) or by Ki67 index (&lt;5% in 61% of the cases). Almost all tumors were HR (hormone receptors) positive (95%) and 4% were HER2 positive (HER2+). According to the intrinsic subtypes described by Cheang et al., 84% of the cases were classified as luminal A, 11.6% as luminal B, 1.5% as HER2 (HR−/HER2+), 2.5% as basal-like and 0.4% as triple negative non basal. Ki67 index was higher in the HER2 and basal-like subgroups (p &lt; 0,05). In contrast, Bcl-2 expression was higher in the luminal subgroup (p &lt; 0,001). All the HER2, triple negative basal like and 87% of the luminal B were pT1b. 20 patients received chemotherapy, mainly based on HER2+ or triple negative status (72.7% and 36.4% respectively). Furthermore, 72.7% of HER2+ BC patients received trastuzumab.

Conclusions: The pT1a, bpN0M0 BC ODISSEE patients were mainly grade I or II, low proliferative HR+/HER2− tumors (i.e. the so-called luminal A subtype). Adjuvant treatment decision was mainly based on the presence of an aggressive phenotype such as HER2+ and triple negative tumors. A further exploration of ER/luminal pathway (FoxA1, GATA3, androgen receptor, Cox-2) and of PI3K/Akt/mTOR pathway (eIF4E, 4EBP, p70S6) is ongoing and will be presented.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-21-01.

Comparison of patient-ventilator interfaces based on their computerized effective dead space

PURPOSE

Non-invasive ventilation is largely used to treat acute and chronic respiratory failure. This ventilation encounters a non-negligible rate of failure related to the used interface/mask, but the reasons for this failure remain unclear. In order to shed light on this issue and to better understand the effects of the geometrical design of interfaces, we aimed to quantify flow, pressure and gas composition in terms of CO(2) and O(2) at the passage through different types of interface (oronasal mask, integral mask and helmet). In particular, we postulated that due to specific gas flow passing throughout the interface, the effective dead space added by the interface is not always related to the whole gas volume included in the interface.

METHODS

Numerical simulations, using computational fluid dynamics, were used to describe pressure, flow and gas composition during ventilation with the different interfaces.

RESULTS

Between the different interfaces the effective dead spaces differed only modestly (110-370 ml), whereas their internal volumes were markedly different (110-10,000 ml). Effective dead space was limited to half the tidal volume for the most voluminous interface, whereas it was close to the interface gas volume for the less voluminous interfaces. Pressure variations induced by the flow ventilation throughout the interface were negligible.

CONCLUSIONS

Effective dead space is not related to the internal gas volume included in the interface, suggesting that this internal volume should not be considered as a limiting factor for their efficacy during non-invasive ventilation. Patient's comfort and synchrony have also to be taken into account.

Abnormal respiratory cilia in non-syndromic Leber congenital amaurosis with CEP290 mutations

BACKGROUND

Leber congenital amaurosis (LCA) is the earliest and most severe inherited retinal degeneration. Isolated forms of LCA frequently result from mutation of the CEP290 gene which is expressed in various ciliated tissues.

METHODS

Seven LCA patients with CEP290 mutations were investigated to study otorhinolaryngologic phenotype and respiratory cilia. Nasal biopsies and brushing were performed to study cilia ultrastructure using transmission electron microscopy and ciliary beating using high-speed videomicroscopy, respectively. CEP290 expression in normal nasal epithelium was studied using real-time RT-PCR.

RESULTS

When electron microscopy was feasible (5/7), high levels of respiratory cilia defects were detected. The main defects concerned dynein arms, central complex and/or peripheral microtubules. All patients had a rarefaction of ciliated cells and a variable proportion of short cilia. Frequent but moderate and heterogeneous clinical and ciliary beating abnormalities were found. CEP290 was highly expressed in the neural retina and nasal epithelial cells compared with other tissues.

DISCUSSION

These data provide the first clear demonstration of respiratory cilia ultrastructural defects in LCA patients with CEP290 mutations. The frequency of these findings in LCA patients along with the high expression of CEP290 in nasal epithelium suggest that CEP290 has an important role in the proper development of both the respiratory ciliary structures and the connecting cilia of photoreceptors. The presence of respiratory symptoms in patients could represent additional clinical criteria to direct CEP290 genotyping of patients affected with the genetically heterogeneous cone-rod dystrophy subtype of LCA.

ZSM-5 nanowires assembly supported on medium surface area foam beta-SiC composite with nanoscopic surface properties

The present study reports the synthesis of supported zeolite with nanoscopic size on the SiC-based composite combining nanoscopic properties, i.e., SiC nanofibers, and macroscopic shaping, i.e., SiC foam with centimeters size. The SiC nanofibers have been obtained by the transformation of the carbon nanofibers by carburization in the presence of SiO vapour and then the zeolite was deposited on the SiC foam support. The different nature of the support results in different morphologies on zeolite crystal.