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1.
Langmuir ; 40(19): 10115-10128, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38703121

RESUMEN

This study investigates the utilization of the conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) as a catalytic material for the 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-mediated oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA). PEDOT films doped with different counterions were electrodeposited on graphite foil. In particular, the mobile anion perchlorate and the polymeric ionomers polystyrenesulfonate, Nafion, and Aquivion were used. The electrocatalytic properties of PEDOT films were evaluated toward the TEMPO redox mediator in the absence and the presence of HMF as a substrate for oxidation reactions. The electrocatalytic HMF oxidation was confirmed to occur at PEDOT electrodes, and it was also found that the chemical nature of PEDOT counterions controls the electrocatalytic conversion of HMF by modulating the kinetics of the electrochemical generation of the oxoammonium cation TEMPO(+). Potentiostatic electrolysis experiments showed that both the reference graphite electrode and PEDOT substrates were able to convert HMF to FDCA with an 80% faradaic efficiency (FE) and a >90% yield (FDCA), but, compared to graphite, the complete conversion of HMF to FDCA required a ca. 30% shorter time when using PEDOT electrodes doped with perchlorate or Aquivion, thanks to their ability to sustain a higher current density in the initial phase of the electrolysis. In addition, while all PEDOT films were chemically stable under the electrochemical conditions herein described, only PEDOT films doped with Aquivion were also mechanically robust and stable against delamination. Thus, the new PEDOT/Aquivion composite may represent the best choice for the implementation of PEDOT-based electrodes in TEMPO-mediated electrocatalytic applications.

2.
Molecules ; 29(2)2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38257206

RESUMEN

Since Mallouk's earliest contribution, dye-sensitized photoelectrochemical cells (DSPECs) have emerged as a promising class of photoelectrochemical devices capable of storing solar light into chemical bonds. This review primarily focuses on metal complexes outlining stabilization strategies and applications. The ubiquity and safety of water have made its splitting an extensively studied reaction; here, we present some examples from the outset to recent advancements. Additionally, alternative oxidative pathways like HX splitting and organic reactions mediated by a redox shuttle are discussed.

3.
Chirurgia (Bucur) ; 118(4): 370-379, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37697999

RESUMEN

Background: This study evaluates the feasibility, efficacy, the complications rate, and the long-term results of laparoscopic treatment of gastroesophageal reflux disease (GERD) at a dedicated center. Materials and Methods: From 01/11/1993 to 01/12/2019, we performed 620 fundoplication surgeries by laparoscopic approach according to Rossetti technique and 160 according to Toupet technique, totally 780 procedures for gastroesophageal reflux disease. The average duration of surgery was 40 minutes (range 19 - 160) for Rossetti fundoplication, 50 (range 30 - 180), and for Toupet 60 (range 45 - 190). All patients were investigated by upper digestive tract radiography, esophagogastroscopy, 24h computerized pH-metry, manometry and scintigraphy to assess esophageal clearance and gastric emptying times. In the 180 (23 %) patients with associated hiatal hernia, direct hiatoplasty was performed in 108 cases, and hiatoalloplasty in the remaining 72. Results: There were no cases of perioperative mortality; the morbidity rate was 6.28 %. We had 16.7 % long-term failures, requiring reintervention in 46 cases (6.5 %). Thirty patients (3.84 %) had to resume occasional 40 mg PPI therapy and 48 patients (6.15 %) had to resume 40 mg PPI therapy continuously. Manometry in these patients revealed lower esophageal sphincter tone between 10- and 16-mm hg with complete and coordinated relaxations. Of the 44 patients who underwent redo surgery 26 were reoperated to repackage a tighter plastic. Six patients required reoperation for dysphagia. Twelve paraesophageal hernias were recorded in the group of patients in whom only hiatoplasty without prosthesis was performed. In all cases, a hiatoplasty with prosthesis was repackaged laparoscopically. Conclusions: We emphasize the importance of accurate morphologic and functional evaluation of the esophagus preoperatively for selection of the most appropriate intervention and postoperatively for evaluation of the causes of failures. In the presence of hiatal hernia, it is always advisable to perform hiatoplasty with the placement of a prosthesis.


Asunto(s)
Reflujo Gastroesofágico , Hernia Hiatal , Laparoscopía , Humanos , Estudios de Seguimiento , Hernia Hiatal/cirugía , Calidad de Vida , Resultado del Tratamiento , Reflujo Gastroesofágico/cirugía
4.
J Org Chem ; 87(12): 7826-7837, 2022 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-35621232

RESUMEN

Indole-decorated glycine derivatives are prepared through an environmentally benign cross-dehydrogenative coupling between N-aryl glycine analogues and indoles (yield of ≤81%). Merging heterogeneous organocatalysis and photocatalysis, C-H functionalization has been achieved by selective C-2 oxidation of N-aryl glycines to afford the electrophilic imine followed by Friedel-Crafts alkylation with indole. The sustainability of the process has been taken into account in the reaction design through the implementation of a metal-free recyclable heterogeneous photocatalyst and a green reaction medium. Scale-up of the benchmark reaction (gram scale, yield of 69%) and recycling experiments (over seven runs without a loss of efficiency) have been performed to prove the robustness of the protocol. Finally, mechanistic studies were conducted employing electron paramagnetic resonance spectroscopy to unveil the roles of the photocatalyst and oxygen in the formation of odd-electron species.


Asunto(s)
Glicina , Indoles , Aminoácidos , Catálisis , Glicina/química , Grafito , Indoles/química , Compuestos de Nitrógeno
5.
Molecules ; 26(19)2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34641499

RESUMEN

(1) Background: Metal dithiocarbamate compounds have long been the subject of research due to their ease of formation, excellent properties and potential applications. However, manganese complexes with dithiocarbamates, to our knowledge, have never been used for medical imaging applications. With the aim of developing a new class of mononuclear manganese(II)-based agents for molecular imaging applications, we performed a specific investigation into the synthesis of mononuclear bis-substituted Mn(II) complexes with dithiocarbamate ligands. (2) Methods: Synthesis in either open or inert atmosphere at different Mn(II) to diethyldithiocarbamate molar ratios were performed and the products characterized by IR, EA, ESI-MS and XRD analysis. (3) Results: We found that only under oxygen-free atmospheric conditions the Mn(II) complex MnL2, where L = diethyldithiocarbamate ligand, is obtained, which was further observed to react with dioxygen in the solid state to form the intermediate superoxo Mn(III) complex [MnL2(η2-O2)]. The existence of the superoxo complex was revealed by mass spectroscopy, and this species was interpreted as an intermediate step in the reaction that led the bis-substituted Mn(II) complex, MnL2, to transform into the tris-substituted Mn(III) complex, MnL3. A similar result was found with the ligand L' (= bis(N-ethoxyethyl)dithiocarbamate). (4) Conclusions: We found that in open atmosphere and in aqueous solution, only manganese(III) diethyldithiocarbamate complexes can be prepared. We report here a new example of a small-molecule Mn(II) complex that efficiently activates dioxygen in the solid state through the formation of an intermediate superoxide adduct.

6.
Chemistry ; 25(9): 2322-2329, 2019 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-30537238

RESUMEN

Localized drug delivery represents one of the most challenging uses of systems based on conductive polymer films. Typically, anionic drugs are incorporated within conductive polymers through electrostatic interaction with the positively charged polymer. Following this approach, the synthetic glucocorticoid dexamethasone phosphate is often delivered from neural probes to reduce the inflammation of the surrounding tissue. In light of the recent literature on the neuroprotective and anti-inflammatory properties of tauroursodeoxycholic acid (TUDCA), for the first time, this natural bile acid was incorporated within poly(3,4-ethylenedioxythiophene) (PEDOT). The new material, PEDOT-TUDCA, efficiently promoted an electrochemically controlled delivery of the drug, while preserving optimal electrochemical properties. Moreover, the low cytotoxicity observed with viability assays, makes PEDOT-TUDCA a good candidate for prolonging the time span of chronic neural recording brain implants.


Asunto(s)
Compuestos Bicíclicos Heterocíclicos con Puentes , Sistemas de Liberación de Medicamentos , Polímeros , Ácido Tauroquenodesoxicólico , Materiales Biocompatibles/química , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Conductividad Eléctrica , Técnicas Electroquímicas/métodos , Humanos , Polímeros/química , Ácido Tauroquenodesoxicólico/química
7.
Chemistry ; 24(41): 10300-10305, 2018 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-29799647

RESUMEN

PEDOT (Poly(3,4-ethylenedioxythiophene)) is one of the most promising electrode materials for biomedical applications like neural recording and stimulation, thanks to its enhanced biocompatibility and electronic properties. Drug delivery by PEDOT is typically achieved by incorporating drugs as dopants during the electrodeposition procedure and a subsequent release can be promoted by applying a cathodic trigger that reduces PEDOT while enabling the drug to diffuse. This approach has several disadvantages including, for instance, the release of contaminants mainly due to PEDOT decomposition during electrochemical release. Herein we describe a new strategy based on the formation of a chemical linkage between the drug and the conductive polymer. In particular, dexamethasone was successfully integrated into a new electropolymerized PEDOT-Dex composite, leading to a self-adjusting drug release system based on a biochemically hydrolysable bond between dexamethasone and PEDOT.

8.
J Allergy Clin Immunol ; 139(4): 1266-1274.e1, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27619824

RESUMEN

BACKGROUND: Celiac disease (CD) is an immune-mediated disorder characterized by an accumulation of immune cells in the duodenal mucosa as a consequence of both adaptive and innate immune responses to undigested gliadin peptides. Mast cells (MCs) are innate immune cells that are a major source of costimulatory signals and inflammatory mediators in the intestinal mucosa. Although MCs have previously been associated with CD, functional studies have never been performed. OBJECTIVE: We aimed at evaluating the role of MCs in the pathogenesis of CD. METHODS: Intestinal biopsy specimens of patients with CD were scored according to the Marsh classification and characterized for leukocyte infiltration and MC distribution. Moreover, MC reactivity to gliadin and its peptides was characterized by using in vitro assays. RESULTS: Infiltrating MCs were associated with the severity of mucosal damage, and their numbers were increased in patients with higher Marsh scores. MCs were found to directly respond to nonimmunodominant gliadin fragments by releasing proinflammatory mediators. Immunohistochemical characterization of infiltrating MCs and the effects of gliadin peptides on intestinal MCs indicated an increase in proinflammatory MC function in advanced stages of the disease. This was also associated with increased neutrophil accumulation, the prevalence of M1 macrophages, and the severity of tissue damage. CONCLUSION: We provide a description of the progressive stages of CD, in which MCs are the hallmark of the inflammatory process. Thus the view of CD should be revised, and the contribution of MCs in the onset and progression of CD should be reconsidered in developing new therapeutic approaches.


Asunto(s)
Enfermedad Celíaca/inmunología , Enfermedad Celíaca/patología , Mastocitos/inmunología , Animales , Degranulación de la Célula/inmunología , Progresión de la Enfermedad , Femenino , Técnica del Anticuerpo Fluorescente , Gliadina/inmunología , Humanos , Inmunohistoquímica , Mucosa Intestinal/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Fragmentos de Péptidos/inmunología
9.
Int Arch Allergy Immunol ; 169(2): 130-4, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27073906

RESUMEN

BACKGROUND: Immunoglobulin (Ig) A deficiency is a primary immunodeficiency in which autoimmunity is frequently observed. Thirty to fifty percent of patients with spontaneous chronic urticaria have autoantibodies that are able to cross-link FcεRI on mast cells and basophils. METHODS: We investigated whether spontaneous chronic urticaria in patients with IgA deficiency meets the criteria for autoimmunity. Four patients were screened for positivity to a skin prick test and an autologous serum skin test and for the presence of other autoimmune diseases. Patient sera were tested for the ability to activate basophils and mast cells in vitro by measuring surface CD63 expression and ß-hexosaminidase release, respectively. RESULTS: The autologous serum test was positive in all patients, and patient sera were found to induce CD63 upregulation on basophils and degranulation of an LAD2 mast cell line. Moreover, all patients were affected by other autoimmune disorders. CONCLUSION: For the first time, these data point out chronic autoimmune urticaria in subjects with an IgA deficiency and confirm that different autoimmune disorders are common among patients with an IgA deficiency. Patients with chronic autoimmune spontaneous urticaria should be screened for IgA deficiency, especially if they are affected by other autoimmune disorders. Thus, spontaneous urticaria could mirror more complex systemic diseases, such as immune deficiency.


Asunto(s)
Autoanticuerpos/inmunología , Enfermedades Autoinmunes/complicaciones , Enfermedades Autoinmunes/inmunología , Deficiencia de IgA/complicaciones , Deficiencia de IgA/inmunología , Urticaria/complicaciones , Urticaria/inmunología , Adolescente , Adulto , Enfermedades Autoinmunes/metabolismo , Basófilos/inmunología , Basófilos/metabolismo , Degranulación de la Célula/inmunología , Femenino , Humanos , Deficiencia de IgA/metabolismo , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Masculino , Mastocitos/inmunología , Mastocitos/metabolismo , Persona de Mediana Edad , Receptores de IgE/metabolismo , Urticaria/metabolismo , Adulto Joven
10.
Inorg Chem ; 55(11): 5245-53, 2016 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-27212146

RESUMEN

A tetracoordinated redox couple, made by [Cu(2-mesityl-4,7-dimethyl-1,10-phenanthroline)2][PF6], 1, and its Cu(II) form [Cu(2-mesityl-4,7-dimethyl-1,10-phenanthroline)2][PF6]2, 2, has been synthesized, and its electrochemical and photochemical features have been investigated and compared with those of a previously published Cu(2+)/Cu(+) redox shuttle, namely, [Cu(2,9-dimethyl-1,10-phenanthroline)2][PF6], 3, and its pentacoordinated oxidized form [Cu(2,9-dimethyl-1,10-phenanthroline)2Cl][PF6], 4. The detrimental effect of the fifth Cl(-) ancillary ligand on the charge transfer kinetics of the redox shuttles has been exhaustively demonstrated. Appropriately balanced Cu-based electrolytes have been then formulated and tested in dye solar cells in combination with a π-extended benzothiadiazole dye. The bis-phenanthroline Cu-complexes, 1 and 2, have been found to provide an overall 4.4% solar energy conversion efficiency, which is more than twice that of the literature benchmark couple, 3 and 4, employing a Cl-coordinated oxidized species and even comparable with the performances of a I(-)/I3(-) electrolyte of analogous concentration. A fast counter-electrode reaction, due to the excellent electrochemical reversibility of 2, and a high electron collection efficiency, allowed through the efficient dye regeneration kinetics exerted by 1, represents two major characteristics of these copper-based electron mediators and may constitute a pivotal step toward the development of a next generation of copper-based efficient iodine-free redox shuttles.

11.
Phys Chem Chem Phys ; 18(19): 13718, 2016 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-27137633

RESUMEN

Correction for 'On the stability of manganese tris(ß-diketonate) complexes as redox mediators in DSSCs' by Stefano Carli et al., Phys. Chem. Chem. Phys., 2016, 18, 5949-5956.

12.
Phys Chem Chem Phys ; 18(8): 5949-56, 2016 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-26751983

RESUMEN

The photoelectrochemical properties and stability of dye sensitized solar cells containing Mn(ß-diketonato)3 complexes, [Mn(III)(acac)3] () (acac = acetylacetonate), [Mn(III)(CF2)3] () (CF2 = 4,4-difluoro-1-phenylbutanate-1,3-dione), [Mn(III)(DBM)3] () (DBM = dibenzoylmethanate), [Mn(II)(CF2)3]TBA (TBA = tetrabutylammonium) () and [Mn(II)(DBM)3]TBA (), have been evaluated. At room temperature, the complexes undergo ligand exchange with 4-tert-butyl-pyridine, an additive commonly used in the solar device to reduce charge recombination at the photoanode. An increased device stability was achieved by using the Z907 dye and passivating the photoanode with short chain siloxanes. It was also found that the Mn(ii)/(iii) couple is involved in the dye regeneration process, instead of Mn(iii)/(iv) (E1/2 > 1 V vs. SCE) previously indicated in the literature.

13.
Phys Chem Chem Phys ; 17(44): 29661-70, 2015 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-26477966

RESUMEN

Different approaches have been explored to increase the water oxidation activity of nanostructured hematite (α-Fe2O3) photoanodes, including doping with various elements, surface functionalization with both oxygen evolving catalysts (OEC) and functional overlayers and, more recently, the introduction of ultrathin oxide underlayers as tunneling back contacts. Inspired by this latter strategy, we present here a photoanode design with a nanometric spin-coated iron oxide underlayer coupled with a mesoporous hematite film deposited by electrophoresis. The electrodes equipped with the thin underlayer exhibit a four-fold improvement in photoactivity over the simple hematite porous film, reaching a stable photocurrent density of ca. 1 mA cm(-2) at 0.65 V versus the saturated calomel electrode (SCE) at pH 13.3 (NaOH 0.1 M) under air mass (AM) 1.5G illumination. A further improvement to 1.5 mA cm(-2) is observed after decoration of the hematite surface with a Fe(iii)-OEC. These results demonstrate that by combining different iron oxide morphologies, it is possible to improve the selectivity of the interfaces towards both electron collection at the back contact and hole transfer to the electrolyte, obtaining an efficient all-iron based photoelectrode entirely realized with simple wet solution scalable procedures.


Asunto(s)
Electrodos , Compuestos Férricos/química , Fotoquímica , Electrones , Microscopía Electrónica de Rastreo , Porosidad
14.
Chemphyschem ; 15(6): 1164-74, 2014 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-24643917

RESUMEN

Hematite photoelectrodes prepared via a hydrothermal route are functionalized with a water oxidation catalyst consisting of amorphous Fe(III) oxide, obtained by successive ionic layer adsorption and reaction. The performances of the catalyst-modified photoanodes are considerably higher than those of the parent electrodes, resulting in a nearly doubled photoanodic current in all the basic aqueous electrolytes explored in this study. The combination of electrochemical impedance spectroscopy and laser flash photolysis indicates that the presence of the catalyst results in enhanced hole trapping in surface reactive states exposed to the electrolyte, allowing for a more successful competition between charge transfer and recombination.

15.
Artículo en Inglés | MEDLINE | ID: mdl-38652052

RESUMEN

Supercapacitors offer notable properties as energy storage devices, providing high power density and fast charging and discharging while maintaining a long cycling lifetime. Although poly(3,4-ethylenedioxythiophene) doped with poly(4-styrenesulfonate) (PEDOT/PSS) has become a gold standard among organic electronics materials, researchers are still investigating ways to further improve its capacitive characteristics. In this work, we introduced Nafion as an alternative polymeric counterion to PSS to form highly capacitive PEDOT/Nafion; its advantageous supercapacitive properties were further improved by treatment with either dimethyl sulfoxide or ethylene glycol. Accordingly, electrochemical characterization of PEDOT/Nafion films revealed their high areal capacitance (22 mF cm-2 at 10 mV/s) and low charge transfer resistance (∼380 Ω), together with excellent volumetric capacitance (74 F cm-3), Coulombic efficiency (99%), and an energy density of 23.1 ± 1.5 mWh cm-3 at a power density of 0.5 W cm-3, resulting from a more effective ion diffusion inside the conductive film, as confirmed by the results of spectroscopic studies. A proof-of-concept symmetric supercapacitor based on PEDOT/Nafion was characterized with a specific capacitance of approximately 15.7 F g-1 and impressive long-term stability (Coulombic efficiency ∼99% and capacitance ∼98.7% after 1000 charging/discharging cycles), overperforming the device based on PEDOT/PSS.

16.
J Bodyw Mov Ther ; 37: 156-163, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38432799

RESUMEN

BACKGROUND: The management of acute postoperative pain after rotator cuff surgery can be challenging. To our knowledge, there are no data available in the literature correlating satisfactory pain control with improvement in terms of function. The purposes of the present study were to evaluate: 1) pain pattern after arthroscopic rotator cuff repair in patients operated with two different techniques (transosseous vs transosseous equivalent); 2) safety/efficacy of three different pharmacological pain control strategies; 3) possible relationship between a correct shoulder pain management protocol in the early post-operative period and patients' functional improvement. METHODS: 114 patients underwent rotator cuff tear repair, either with a Transosseus or a Transosseus equivalent technique. 62 (54%) were male and 52 (46%) were female. The average age was 59 ± 9 years. They were randomly assigned into three different pain management protocols: Paracetamol as needed (max 3 tablets/day) for 1 week (Protocol A), Paracetamol + Codein 1 tablet three times per day for 7 days (Protocol B), or Paracetamol + Ibuprofen 1 tablet two times per day for 7 days (Protocol C). Immediate passive mobilization of the operated shoulder was allowed. VAS and Passive Flexion values were recorded at 7 (T1), 15 (T2) and 30 (T3) days post-surgery. DASH values were recorded at 90 days post-surgery. All patients were asked to register any kind of signs/symptoms that may appear during drug assumption according to each pain management protocols. RESULTS: All the pain management protocols administered were well tolerated by all the study population, and no adverse signs/symptoms were highlighted during drug assumption. Pain pattern: in both surgical techniques, patients within Protocol A were associated with worst results in terms of mean VAS at each time point examined when compared to Protocol B and C (p < 0,05). In patients within Protocol A, no statistically significant differences were found at each point time examined comparing the two surgical techniques, with the exception of T2, where the TO was associated with an higher VAS value than TOE (p < 0.05). No differences were highlighted in Protocol B and C when comparing the values between two surgical techniques. ROM: in both surgical techniques, patients within Protocol A were associated with worst results in terms of mean PROM at each time point examined when compared to Protocol B and C (p < 0,05). In the TO group, patients within Protocol B had better PROM values at T1 (p < 0,05) and T2 (p < 0,05) compared to Protocol C, but no differences were highlighted at T3. In the TOE group, no statistically significant differences were found between patients within Protocol B and C at each time point examined. DASH: In the TO group, no statistically significant differences were found regarding the DASH values comparing Protocol B vs Protocol C, but they were highlighted comparing the values between Protocol A and Protocol B (p < 0,05), and between Protocol A and Protocol C (p < 0,05). Similar results were recorded in the TOE group. CONCLUSION: Post-operative pain is influenced by the surgical technique used being transosseous more painful in the first 15 days after surgery. Oral anti-inflammatory drugs are a feasible strategy to appropriately control post-operative pain. An association between Paracetamol and either Codein or Ibuprofen can lead to better outcomes in terms of VAS reduction and early recovery of passive ROM.


Asunto(s)
Lesiones del Manguito de los Rotadores , Hombro , Humanos , Femenino , Masculino , Persona de Mediana Edad , Anciano , Manejo del Dolor , Lesiones del Manguito de los Rotadores/cirugía , Acetaminofén , Ibuprofeno , Dolor de Hombro/terapia , Dolor Postoperatorio/tratamiento farmacológico , Comprimidos
17.
ACS Appl Mater Interfaces ; 16(12): 14864-14882, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38483816

RESUMEN

This research introduces a novel series of perfluorinated Zn(II) porphyrins with positive oxidation potentials designed as sensitizers for photoelectrosynthetic cells, with a focus on promoting the oxidation of benzyl alcohol (BzOH) mediated by the 2,2,6,6-tetramethyl-1-piperidine N-oxyl (TEMPO) organocatalyst. Three dyes, CLICK-3, CLICK-4, and BETA-4, are meticulously designed to explore the impact of substituents and their positions on the perfluorinated porphyrin ring in terms of redox potentials and energy level alignment when coupled with SnO2/TiO2-based photoanodes and TEMPO mediator. A comprehensive analysis utilizing spectroscopy, electrochemistry, photophysics, and computational techniques of the dyes in solution and sensitized thin films unveils an enhanced charge-separation character in the 4D-π-1A type BETA-4. Incorporating four dimethylamino donor groups at the periphery of the porphyrin ring and a BTD-accepting linker at the ß-pyrrolic position equips the structure with a more efficient donor-acceptor system. This enhancement ensures improved light-harvesting capacity, resulting in a doubled incident photon-to-current conversion efficiency (IPCE% ≃30%) in the presence of LiI compared to meso-substituted dyes CLICK-3 and CLICK-4. Sensitizing SnO2/TiO2 thin films with BETA-4 successfully promotes the photooxidation of benzyl alcohol (BzOH) in the presence of the rapid TEMPO radical catalyst, yielding photocurrents of approximately 125 µA/cm2 in an optimized TBPy/LiClO4/ACN electrolyte. Notably, when lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) replaces TBPy as the base for TEMPO-catalyzed BzOH oxidation, a remarkable photocurrent of around 800 µA/cm2 is achieved, marking one of the highest values reported for this photoelectrochemical reaction to date. This study underscores that the proper functionalization of perfluorinated zinc porphyrins positions these dyes as ideal candidates for sensitizing SnO2/TiO2 in the photodriven oxidation of BzOH. It also highlights the crucial role of carefully tuning electrolyte composition based on the electronic properties of molecular sensitizers.

18.
Phys Chem Chem Phys ; 15(31): 13083-92, 2013 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-23820552

RESUMEN

Indium tin oxide (ITO) surfaces of triple junction photovoltaic cells were functionalized with oxygen evolving catalysts (OECs) based on amorphous hydrous earth-abundant metal oxides (metal = Fe, Ni, Co), obtained by straightforward Successive Ionic Layer Adsorption and Reaction (SILAR) in an aqueous environment. Functionalization with Fe(iii) oxides gave the best results, leading to photoanodes capable of efficiently splitting water, with photocurrent densities up to 6 ± 1 mA cm(-2) at 0 V vs. the reversible hydrogen electrode (RHE) under AM 1.5 G simulated sunlight illumination. The resulting Solar To Hydrogen (STH) conversion efficiencies, measured in two electrodes configuration, were in the range 3.7-5%, depending on the counter electrode that was employed. Investigations on the stability showed that these photoanodes were able to sustain 120 minutes of continuous illumination with a < 10% photocurrent loss at 0 V vs. RHE. Pristine photoanodic response of the cells could be fully restored by an additional SILAR cycle, evidencing that the observed loss is due to the detachment of the more weakly surface bound catalyst.


Asunto(s)
Suministros de Energía Eléctrica , Oxígeno/química , Energía Solar , Agua/química , Catálisis , Oxidación-Reducción
19.
Surg Endosc ; 27(7): 2613-8, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23397503

RESUMEN

BACKGROUND: Several techniques are described in the literature about laparoscopic treatment of the right colon. Among them, laparoscopic-assisted colectomy (LAC) with creation of an extracorporeal ileocolonic anastomosis remains the favourite approach in most centers. So far, total laparoscopic colectomy (TLC) with intracorporeal anastomosis is not widely performed, because it requires adequate skills and competence in the use of mechanical linear staplers and laparoscopic manual sutures. The purpose of this study was to determine prospectively if TLC offers some advantages in short-term outcomes over LAC. METHODS: A prospective comparative study was designed for 80 consecutive patients who were alternatively treated with TLC and LAC for right colon neoplasms. The following data were collected: operative time, intra- and postoperative complication rate, time to bowel movement, hospitalization time, length of minilaparotomy, number of harvested lymph nodes, and specimen length. RESULTS: Operative time in TLC resulted significantly longer than in LAC (230 vs. 203 min), complication rate was similar in both groups, with no case of anastomotic dehiscence, two anastomotic bleedings in TLC vs. three in LAC and one case of postoperative ileus for each group. One case of death occurred in LAC patient developing a postoperative severe cardiopulmonary syndrome. Time to first flatus was in favour of TLC (2.2 vs. 2.6 days), whereas hospitalization was comparable. As regards to the oncological parameters of radicality, the specimen length was superior in TLC group, but the number of lymph nodes excised was equivalent. The length of the minilaparotomy was clearly shorter in TLC group (5.5 vs. 7.2 cm). CONCLUSIONS: No evidence of relevant differences in terms of functional and safety outcomes between the two laparoscopic procedures. TLC determines less abdominal manipulation and shorter incision length, but clear advantages must be still demonstrated. Larger series are necessary to test the superiority of totally laparoscopic procedures for right colectomy.


Asunto(s)
Colectomía/métodos , Neoplasias del Colon/cirugía , Laparoscopía , Evaluación del Resultado de la Atención al Paciente , Adulto , Anciano , Anciano de 80 o más Años , Anastomosis Quirúrgica/efectos adversos , Colectomía/efectos adversos , Femenino , Flatulencia , Hemorragia Gastrointestinal/etiología , Hematoma/etiología , Humanos , Ileus/etiología , Masculino , Persona de Mediana Edad , Tempo Operativo , Estudios Prospectivos , Recuperación de la Función
20.
J Laparoendosc Adv Surg Tech A ; 33(1): 44-51, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35675688

RESUMEN

Background: Laparoscopic sleeve gastrectomy (LSG) is associated with the long-term development of gastroesophageal reflux disease (GERD). Recent studies on LSG with fundoplication showed a lower rate of postoperative GERD than LSG alone; however, there is a lack of objective instrumental data in the literature. This study aimed to evaluate whether and how fundoplication associated with Sleeve Gastrectomy affects the esophagogastric physiology. Materials and Methods: This prospective observational study included 20 patients with morbid obesity, GERD, and lower esophageal sphincter (LES) hypotonia. All the patients underwent LSG with Rossetti fundoplication. High-resolution manometry was performed pre- and postoperatively. All the patients completed the 6 months follow-up. Results: The fundoplication increased LES tone in all patients. The increase in the LES tone was statistically significant (330% increase). The integrated relaxation pressure and the distal contractile integral both increased accordingly, indicating an increased esophageal effort to pass through the modified esophagogastric junction. Conclusion: Rossetti fundoplication associated with LSG increased LES tone and decreased the chance of developing long-term GERD after LSG.


Asunto(s)
Reflujo Gastroesofágico , Laparoscopía , Obesidad Mórbida , Humanos , Esfínter Esofágico Inferior/cirugía , Fundoplicación , Reflujo Gastroesofágico/cirugía , Gastrectomía , Manometría , Obesidad Mórbida/cirugía , Resultado del Tratamiento
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