A Modular and Catalytic Methodology To Access 2,5-Furan-Based Phenylene/Thiophene Oligomers through a One-Pot Decarboxylative Cross-Coupling from 5-Bromofurfural.

A library of 2,5-furan-based phenylene/thiophene oligomers were synthesized starting from 5-bromofurfural, a derivative of biomass-derived furfural. Varied electronic groups are coupled onto the furan motif, followed by the installation of a phenylene or thiophene central linker through a one-pot Pd-catalyzed decarboxylative cross-coupling reaction. Resulting oligomers containing the furan-phenylene-furan core possess high photoluminescent quantum yields in solution (83-98%), which are crucial for optoelectronic devices. Absorbance and photoluminescence maxima are tuned by changing peripheral functional groups and the center linker coupled onto the furan backbone.

IL-22(+)CD4(+) T cells promote colorectal cancer stemness via STAT3 transcription factor activation and induction of the methyltransferase DOT1L.

Little is known about how the immune system impacts human colorectal cancer invasiveness and stemness. Here we detected interleukin-22 (IL-22) in patient colorectal cancer tissues that was produced predominantly by CD4(+) T cells. In a mouse model, migration of these cells into the colon cancer microenvironment required the chemokine receptor CCR6 and its ligand CCL20. IL-22 acted on cancer cells to promote activation of the transcription factor STAT3 and expression of the histone 3 lysine 79 (H3K79) methytransferase DOT1L. The DOT1L complex induced the core stem cell genes NANOG, SOX2, and Pou5F1, resulting in increased cancer stemness and tumorigenic potential. Furthermore, high DOT1L expression and H3K79me2 in colorectal cancer tissues was a predictor of poor patient survival. Thus, IL-22(+) cells promote colon cancer stemness via regulation of stemness genes that negatively affects patient outcome. Efforts to target this network might be a strategy in treating colorectal cancer patients.

Could Toll-like Receptor 2 Serve as Biomarker to Detect Advanced Gastric Cancer?

Gastric cancer is one of the five most common types of cancer worldwide. Due to the heterogeneous course and the involvement of many risk factors, its treatment and diagnosis is an important challenge for modern medicine. Recent studies have emphasized the i role of Toll-like receptors (TLRs) expressed on selected cells of the immune system in the pathogenesis of gastric cancer. The aim of this study was to determine the prevalence of TLR2 on T lymphocytes, B lymphocytes, monocytes, and dendritic cells in patients diagnosed with gastric cancer, with particular emphasis on the stage of the disease. Based on the obtained results, we have shown that patients with gastric cancer are characterized by a higher percentage of all tested populations of peripheral blood immune cells expressing TLR2 in relation to patients from the control group. Moreover, a detailed analysis of the collected results showed a significant link between TLR2 and the stage of the disease.

A historical perspective on porphyrin-based metal-organic frameworks and their applications.

Porphyrins are important molecules widely found in nature in the form of enzyme active sites and visible light absorption units. Recent interest in using these functional molecules as building blocks for the construction of metal-organic frameworks (MOFs) have rapidly increased due to the ease in which the locations of, and the distances between, the porphyrin units can be controlled in these porous crystalline materials. Porphyrin-based MOFs with atomically precise structures provide an ideal platform for the investigation of their structure-function relationships in the solid state without compromising accessibility to the inherent properties of the porphyrin building blocks. This review will provide a historical overview of the development and applications of porphyrin-based MOFs from early studies focused on design and structures, to recent efforts on their utilization in biomimetic catalysis, photocatalysis, electrocatalysis, sensing, and biomedical applications.

Initial Results of Antegrade Laser Fenestrations Using Image Fusion Guidance and Company Manufactured Stent Grafts in Complex Aortic Aneurysm Repair.

OBJECTIVE: The aim was to describe initial outcomes of physician modified stent grafts using antegrade laser fenestrations and image fusion guidance (LEVAR) and company manufactured custom made (CM) stent grafts for the treatment of complex abdominal aortic aneurysms (CAAAs), thoraco-abdominal aortic aneurysms (TAAAs) and type I endoleaks (T1ELs). METHODS: This was a retrospective single centre study. All LEVAR and Zenith (Cook) CM stent graft procedures between 1 January 2012 and 31 December 2018 were reviewed. Endpoints included intra-operative adverse events (IOAEs), in hospital mortality, re-interventions, target vessel patency, and 12 month outcomes (overall survival, freedom from re-intervention, target vessel patency). Outcomes at 12 months were estimated using the Kaplan-Meier method. RESULTS: A hundred patients were identified and included in the study. All patients were deemed unfit for open repair. The cohort included 22 LEVAR and 78 CM stent grafts. LEVAR cases included painful aneurysms (n = 5), > 65 mm aneurysms (n = 10), anatomical constrains and/or presence of previous renal stents (n = 7) or cases declined by the manufacturer planning centre (n = 2). IOAEs were recorded in 41% of cases (n = 9) in the LEVAR group vs. 10% (n = 8, p = .002) in the CM group. The in hospital mortality rate in the LEVAR group was 9% (n = 2) vs. 4% (n = 3, p = .30) in the CM group. The median follow up duration was 22 months (7 - 38) in the LEVAR group and 28 months (11 - 78) in the CM group. The estimate of overall survival at one year was 91% in both groups. The freedom from re-intervention rate at one year was 58% in the LEVAR group vs. 87% in the CM group. The target vessel patency rates at one year were 95% in both groups. CONCLUSION: In high risk patients deemed unfit for open repair, LEVAR may provide satisfactory 12 month overall survival and target vessel patency rates, though reported IOAE, mortality, and re-interventions rates were high thus requiring close and extensive follow up.

Combination of Quadruple Antegrade and Retrograde In Situ Stent-Graft Laser Fenestration in the Management of a Complex Abdominal Aortic Aneurysm.

BACKGROUND: We report a case of juxtarenal abdominal aortic aneurysm-anatomically unsuitable for conventional endovascular repair because of narrow distal aorta-successfully treated by endovascular repair facilitated by in situ laser fenestration. METHODS AND RESULTS: An aortic stent graft was inserted to exclude a juxtarenal aneurysm: under image fusion guidance, antegrade in situ laser fenestration allowed to perfuse superior mesenteric artery and both renal arteries. After complementary insertion of an extended aortouni-iliac stent graft, retrograde in situ laser fenestration was performed to perfuse the contralateral left iliac artery, in order to overcome a narrow distal aorta. Postoperative course was uneventful. Six month's CT showed an excluded aneurysm, patency of the inserted stents and the absence of endoleak. CONCLUSIONS: In situ laser fenestration seems to be an effective solution for endovascular therapy of complex juxtarenal aneurysms. In this case of narrow distal aorta it was a suitable alternative to overcome endovascular aneurysm repair anatomical restrictions and to prevent other additional open surgical interventions.

Molecular Copper(I)-Copper(II) Photosensitizer-Catalyst Photoelectrode for Water Oxidation.

Copper(II)-based electrocatalysts for water oxidation in aqueous solution have been studied previously, but photodriving these systems still remains a challenge. In this work, a bis(diimine)copper(I)-based donor-chromophore-acceptor system is synthesized and applied as the light-harvesting component of a photoanode. This molecular assembly was integrated onto a zinc oxide nanowire surface, and upon photoexcitation, chronoamperometric studies reveal that the integrated triad can inject electrons directly into the conduction band of zinc oxide, generating oxidizing equivalents that are then transferred to a copper(II) water oxidation catalyst in aqueous solution, yielding O2 from water with a Faradaic efficiency of 76%.

Morphological Engineering of Winged Au@MoS2 Heterostructures for Electrocatalytic Hydrogen Evolution.

Molybdenum disulfide (MoS2) has been recognized as a promising cost-effective catalyst for water-splitting hydrogen production. However, the desired performance of MoS2 is often limited by insufficient edge-terminated active sites, poor electrical conductivity, and inefficient contact to the supporting substrate. To address these limitations, we developed a unique nanoarchitecture (namely, winged Au@MoS2 heterostructures enabled by our discovery of the "seeding effect" of Au nanoparticles for the chemical vapor deposition synthesis of vertically aligned few-layer MoS2 wings). The winged Au@MoS2 heterostructures provide an abundance of edge-terminated active sites and are found to exhibit dramatically improved electrocatalytic activity for the hydrogen evolution reaction. Theoretical simulations conducted for this unique heterostructure reveal that the hydrogen evolution is dominated by the proton adsorption step, which can be significantly promoted by introducing sufficient edge active sites. Our study introduces a new morphological engineering strategy to make the pristine MoS2 layered structures highly competitive earth-abundant catalysts for efficient hydrogen production.

From Transition Metals to Lanthanides to Actinides: Metal-Mediated Tuning of Electronic Properties of Isostructural Metal-Organic Frameworks.

Isostructural metal-organic frameworks (MOFs) have been prepared from a variety of metal-oxide clusters, including transition metals, lanthanides, and actinides. Experimental and calculated shifts in O-H stretching frequencies for hydroxyl groups associated with the metal-oxide nodes reveal varying electronic properties for these units, thereby offering opportunities to tune support effects for other materials deposited onto these nodes.

Parallel Grafts Used in Combination with Physician-Modified Fenestrated Stent Grafts for Complex Aortic Aneurysms in High-risk Patients with Hostile Anatomies.

BACKGROUND: The objective of the study was to evaluate the feasibility and early outcomes of complex aortic aneurysm repair in high-risk patients with hostile anatomies using both parallel stents and physician-modified stent graft (PMSG) techniques to address the renovisceral arteries. METHODS: Consecutive patients with complex suprarenal (SRA) and thoracoabdominal aortic aneurysms (TAAAs) undergoing endovascular repair using combined parallel stents technique and PMSG between September 2013 and November 2015 were evaluated. All patients required prompt aneurysm treatment. Fenestrations to preserve branch vessels were created in thoracic stent grafts. Depending on the anatomy, chimney or snorkel stents were deployed in renal or visceral arteries as complementary technique to overcome severe angulations or preexisting suprarenal stent. Preoperative, intraoperative, and postoperative data were recorded by means of a prospectively maintained database. RESULTS: Six high-risk patients with TAAA (type I: n = 2, type III: n = 1) and SRA (n = 3) underwent endovascular repair using both parallel stents technique and PMSG. Indications were painful aneurysms (n = 1) and >70-mm rapidly enlarging aneurysms (n = 5). Ten thoracic components were used, of which 6 were modified intraoperatively. Twenty-one renovisceral arteries were revascularized, using dedicated fenestrations (n = 10, 47.7%), chimney (n = 7, 33.3%), and snorkel stents (n = 4, 19%). The mean operative time was 326 ± 82 min including the device modification time. The mean time for graft modification was 90 ± 15 min. In 1 patient, a rescue chimney stent intended to the superior mesenteric artery was deployed because of failed cannulation through the dedicated fenestration. Technical success rate was 83.3%. One patient died during the early postoperative course from severe stroke. Among surviving patients, 3 required early reinterventions for iliac occluder-related type II endoleak (n = 1), type Ia endoleak (n = 1), and gastroduodenal artery embolization (n = 1). The mean follow-up was 14.2 ± 4.8 months. One early gutter-related type I endoleak resolved during follow-up. No other complications occurred, and all target vessels remained patent. CONCLUSIONS: PMSG combined with parallel stent provided acceptable short-term results in specific presentation of SRA and TAAA with hostile anatomies in selected high-risk patients with contraindication for standard fenestrated/branched grafts. More reliable outcomes require larger population and follow-up.

Excimer Formation and Symmetry-Breaking Charge Transfer in Cofacial Perylene Dimers.

The use of multiple chromophores as photosensitizers for catalysts involved in energy-demanding redox reactions is often complicated by electronic interactions between the chromophores. These interchromophore interactions can lead to processes, such as excimer formation and symmetry-breaking charge separation (SB-CS), that compete with efficient electron transfer to or from the catalyst. Here, two dimers of perylene bound either directly or through a xylyl spacer to a xanthene backbone were synthesized to probe the effects of interchromophore electronic coupling on excimer formation and SB-CS using ultrafast transient absorption spectroscopy. Two time constants for excimer formation in the 1-25 ps range were observed in each dimer due to the presence of rotational isomers having different degrees of interchromophore coupling. In highly polar acetonitrile, SB-CS competes with excimer formation in the more weakly coupled isomers followed by charge recombination with τCR = 72-85 ps to yield the excimer. The results of this study of perylene molecular dimers can inform the design of chromophore-catalyst systems for solar fuel production that utilize multiple perylene chromophores.

Emergency Endovascular Interventions for Ruptured Descending Thoracic Aortic Aneurysm.

BACKGROUND: Ruptured descending thoracic aortic aneurysm (rDAA) is a rare but devastating condition. Open aortic surgery which uses cardiopulmonary bypass is associated with a high mortality. Thoracic endovascular aortic repair (TEVAR) is a less-invasive approach for which it remains unclear whether outcomes are superior or equivalent to open aortic surgery. In this study, we report our early and midterm outcomes with TEVAR for rDAA. METHODS: This is an observational, retrospective, single-center study which included patients with rDAA and treated by TEVAR. The main objective was the 30-day in-hospital mortality. Secondary end points were 30-day in-hospital morbidity, 2-year mortality, and technical problems encountered during procedures. RESULTS: Twenty-five patients were included: 14 men and 11 women with a median age of 76 years (69-82 years). Thirty-day in-hospital mortality rate was 36% (95% confidence interval [CI], 20.6-57.9; n = 9), and the 2-year mortality rate was 44% (95% CI, 27.94-66.72; n = 11). Fifteen patients (60%) presented at least 1 major complication, and 8 of those patients had a second surgery because of it. There were 9 technical problems encountered that required additional open procedures to successfully deploy the aortic stent graft: lack of vascular access in 2 cases (8%), short proximal neck in 3 cases (12%), and short distal neck in 4 cases (16%). CONCLUSIONS: Mortality and morbidity remain high in patients treated for rDAA by TEVAR. Nonetheless, TEVAR remains an interesting alternative to open aortic surgery especially for older patients with a poor general health and functional status.

Effect of Perylene Photosensitizer Attachment to [Pd(triphosphine)L]2+ on CO2 Electrocatalysis.

Two new covalently linked chromophore-CO2 reduction catalyst systems were prepared using a perylene chromophore and a bis[(dicyclohexylphosphino)ethyl]phenylphosphinopalladium(II) catalyst. The primary goal of this study is to probe the influence of photosensitizer attachment on the electrocatalytic performance. The position either para or meta to the phosphorus on the phenyl group of the palladium complex was linked via a 2,5-xylyl group to the 3 position of perylene. The electrocatalytic CO2 reduction activity of the palladium complex is maintained in the meta-linked system, but is lost in the para-linked system, possibly because of unfavorable interactions of the perylene chromophore with the glassy carbon electrode used. Following selective photoexcitation of the perylene, an enhanced perylene excited-state decay rate was observed in the palladium complexes compared to perylene attached to the free ligands. This decrease is accompanied by formation of the perylene cation radical, showing that electron transfer from perylene to the palladium catalyst occurs. Electron transfer and charge recombination were both found to be faster in the para-linked system than in the meta-linked one, which is attributed to stronger electronic coupling in the former. These results illustrate the need to carefully tune the electronic coupling between a photosensitizer chromophore and the catalyst to promote photodriven electron transfer yet inhibit adverse electronic effects of the chromophore on electrocatalysis.

Direct C-F bond formation using photoredox catalysis.

We have developed the first example of a photoredox catalytic method for the formation of carbon-fluorine (C-F) bonds. The mechanism has been studied using transient absorption spectroscopy and involves a key single-electron transfer from the (3)MLCT (triplet metal-to-ligand charge transfer) state of Ru(bpy)3(2+) to Selectfluor. Not only does this represent a new reaction for photoredox catalysis, but the mild reaction conditions and use of visible light also make it a practical improvement over previously developed UV-mediated decarboxylative fluorinations.

Impact of intraoperative adverse events during branched and fenestrated aortic stent grafting on postoperative outcome.

OBJECTIVE: Fenestrated and branched endovascular devices are increasingly used for complex aortic diseases, and despite the challenging nature of these procedures, early experiences from pioneering centers have been encouraging. The objectives of this retrospective study were to report our experience of intraoperative adverse events (IOAEs) during fenestrated and branched stent grafting and to analyze the impact on clinical outcomes. METHODS: Consecutive patients treated with fenestrated and branched stent grafting in a tertiary vascular center between February 2006 and October 2013 were evaluated. A prospectively maintained computerized database was scrutinized and updated retrospectively. Intraoperative angiograms were reviewed to identify IOAEs, and adverse events were categorized into three types: target vessel cannulation, positioning of graft components, and intraoperative access. Clinical consequences of IOAEs were analyzed to ascertain whether they were responsible for death or moderate to severe postoperative complications. RESULTS: During the study period, 113 consecutive elective patients underwent fenestrated or branched stent grafting. Indications for treatment were asymptomatic complex abdominal aortic aneurysms (CAAAs, n = 89) and thoracoabdominal aortic aneurysms (TAAAs, n = 24). Stent grafts included fenestrated (n = 79) and branched (n = 17) Cook stent grafts (Cook Medical, Bloomington, Ind), Ventana (Endologix, Irvine, Calif) stent grafts (n = 9), and fenestrated Anaconda (Vascutek Terumo, Scotland, UK) stent grafts (n = 8). In-hospital mortality rates for the CAAA and TAAA groups were 6.7% (6 of 89) and 12.5% (3 of 24), respectively. Twenty-eight moderate to severe complications occurred in 21 patients (18.6%). Spinal cord ischemia was recorded in six patients, three of which resolved completely. A total of 37 IOAEs were recorded in 34 (30.1%) patients (22 CAAAs and 12 TAAAs). Of 37 IOAEs, 15 (40.5%) resulted in no clinical consequence in 15 patients; 17 (45.9%) were responsible for moderate to severe complications in 16 patients, and five (13.5%) led to death in four patients. The composite end point death/nonfatal moderate to severe complication occurred more frequently in patients with IOAEs compared with patients without IOAEs (20 of 34 vs 12 of 79; P < .0001). CONCLUSIONS: In this contemporary series, IOAEs were relatively frequent during branched or fenestrated stenting procedures and were often responsible for significant complications.

Impaired viscosity of gastric secretion and its mucin content as potential contributing factors to the development of chronic constipation.

BACKGROUND: The alimentary tract mucosa continuously releases mucus-rich secretion. Mucin, the major component of mucus, determines its viscosity and provides lubrication for the luminal content of indigestible food particles. AIMS: To measure mucin secretion rate and its viscosity in patients with chronic constipation (CC) and in asymptomatic volunteers. METHODS: Nineteen patients with symptoms of CC and 19 controls were included in the study. Mucin secretion and viscosity were assessed in aspirated gastric juice in basal conditions and after stimulation with pentagastrin (1 h each). Mucin content was tested by PAS methodology. Viscosity was measured using cone/plate digital viscometer. RESULTS: Mucin secretion rates in basal and stimulated conditions in controls were 65 and 42 % higher than in patients with CC (P < 0.05 and P < 0.001, respectively). Basal viscosity in controls was 48 % higher than in CC (P < 0.05) at the lowest and 55 % higher (P < 0.05) at the middle velocities. Viscosity in pentagastrin-stimulated conditions in controls was 71 % higher than in CC (P < 0.01) at the lowest and 35 % higher (P < 0.05) at the middle velocities. CONCLUSIONS: (1) The significantly lower rate of soluble mucin secretion in patients with CC than in normal volunteers may reflect impairment in mucin-related lubrication. (2) Significantly lower viscosity of gastric secretion in patients with CC may result from the lower rate of mucin secretion and may also diminish lubrication within the alimentary tract. (3) This may potentially set the stage for the development of symptoms related to chronic constipation and open a new therapeutic avenue for this patient population.

A novel hybrid approach using antegrade visceral debranching from both axillary arteries for thoracoabdominal aneurysm repair.

Hybrid aortic surgery combining visceral debranching and stent grafting is an alternative to conventional open surgery and branched stent grafting for thoracoabdominal aneurysm repair. Visceral aortic branch bypasses are usually performed from the iliac arteries or the infrarenal or ascending aorta. Herein, we describe a new debranching technique to treat a painful Crawford type III thoracoabdominal aneurysm in a high-risk patient who was deemed unsuitable for open, endovascular, or traditional hybrid repair. The superior mesenteric artery and the right renal arteries were exposed via a right retroperitoneal approach and revascularized from the right axillary artery. Splenic and left renal arteries were exposed via a left retroperitoneal approach and revascularized from the left axillary artery.

Molecular copper(I)-sensitized photoanodes for alcohol oxidation under ambient conditions.

Dye-sensitized photoelectrochemical cells can enable the production of molecules currently accessible through energetically demanding syntheses. Copper(I)-based dyes represent electronically tunable charge transfer and separation systems. Herein, we report a Cu(I)-bisdiimine donor-chromophore-acceptor dye with an absorbance in the visible part of the solar spectrum composed of a phenothiazine electron donor, and dipyrido[3,2-a:2',3'-c]phenazine electron acceptor. This complex is incorporated onto a zinc oxide nanowire semiconductor surface effectively forming a photoanode that is characterized spectroscopically and electrochemically. We investigate the photo-oxidation of hydroquinone, and the photosensitization of 2,2,6,6-tetramethylpiperidine-1-oxyl and N-hydroxyphthalimide for the oxidation of furfuryl alcohol to furfuraldehyde, resulting in near quantitative conversions, with poor selectivity to the alcohol.

Effects of increasing ligand conjugation in Cu(I) photosensitizers on NiO semiconductor surfaces.

Dye-sensitized photoelectrodes may be used as heterogeneous components for fuel-forming reactions in photoelectrochemical cells. There has been increasing interest in developing Earth-abundant cheaper photosensitizers based on first-row transition metals. We describe here the synthesis, characterization, and study of the ground and excited state properties of three Cu(I) complexes bearing ligands with varying electron-accepting capacities and conjugation that may act as photosensitizers for wide bandgap semiconductors. Femtosecond transient absorption studies indicate that the nature of the final excited state is dictated by the extent of conjugation in the electron-accepting ligand, where shorter conjugation leads to the formation of a singly reduced ligand and longer conjugation leads to the formation of a ligand-centered final excited state. These complexes were surface anchored onto nanostructured NiO on conductive fluorine-doped tin oxide glass to fabricate photocathodes. It was found that even though the ligands with increasing conjugation have an effect on the formation of the final excited state in solution, all complexes exhibit similar photocurrents upon white light illumination, suggesting that charge transfer to NiO happens in advance of the formation of the final excited state.

Long live(d) CsPbBr3 superlattices: colloidal atomic layer deposition for structural stability.

Superlattice formation afforded by metal halide perovskite nanocrystals has been a phenomenon of interest due to the high structural order induced in these self-assemblies, an order that is influenced by the surface chemistry and particle morphology of the starting building block material. In this work, we report on the formation of superlattices from aluminum oxide shelled CsPbBr3 perovskite nanocrystals where the oxide shell is grown by colloidal atomic layer deposition. We demonstrate that the structural stability of these superlattices is preserved over 25 days in an inert atmosphere and that colloidal atomic layer deposition on colloidal perovskite nanocrystals yields structural protection and an enhancement in photoluminescence quantum yields and radiative lifetimes as opposed to gas phase atomic layer deposition on pre-assembled superlattices or excess capping group addition. Structural analyses found that shelling resulted in smaller nanocrystals that form uniform supercrystals. These effects are in addition to the increasingly static capping group chemistry initiated where oleic acid is installed as a capping ligand directly on aluminum oxide. Together, these factors lead to fundamental observations that may influence future superlattice assembly design.