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1.
Small ; : e2311472, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38651243

RESUMEN

Covalent organic frameworks (COFs), which have layered stacking structures, extended π-conjugation, and periodic frameworks have become a promising class of materials for a wide range of applications. However, their synthetic pathways frequently need high temperatures, enclosed systems under high pressures, an inert atmosphere, and extended reaction time, which restrict their practicality in real-world applications. Herein, the use of gamma irradiation is presented to synthesize highly crystalline COFs at room temperature under an open-air condition within a short time. This is demonstrated that there is no significant difference in crystallinity of COFs by gamma irradiation under air, N2 or Ar atmosphere conditions. Moreover, this approach can successfully fabricate COFs in the vessel with different degrees of transparency or even in a plastic container. Importantly, this strategy is applicable not only to imine linkage of COFs but also effective to the imide linkages of COFs. Most importantly, these COFs demonstrate improved crystallinity, surface area, and thermal stability in comparison to the corresponding materials synthesized via the solvothermal method. Finally, a COF synthesized through gamma irradiation exhibits remarkable photocatalytic activity in promoting the sacrificial hydrogen evolution from water, displaying a more catalytic efficiency compared with that of its solvothermal analogue.

3.
BMC Anesthesiol ; 23(1): 19, 2023 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-36631777

RESUMEN

This article represents the response to the inquiries adopted by Dr. Raghuraman M Sethuraman, M.D., regarding our recently published study which compared the erector spinae plane block (ESPB) versus paravertebral block (PVB) regarding postoperative analgesic consumption following breast surgeries (Elewa et al, BMC Anesthesiol 22: 1-9, 2022). We would like to introduce our appreciation and gratitude to the author for his interest in our work, despite being inaccurate in some of his comments.


Asunto(s)
Neoplasias de la Mama , Bloqueo Nervioso , Humanos , Femenino , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/prevención & control , Mastectomía , Analgésicos
4.
Environ Sci Pollut Res Int ; 30(12): 32371-32382, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36460890

RESUMEN

The removal of heavy metal ions from wastewater has attracted considerable interest because of their toxicity. Adsorption is one of the most promising methods for the removal of heavy metal ions due to its simplicity and effectiveness. Recently, covalent organic frameworks (COFs) have become promising adsorbents for effective wastewater remediation. However, many building blocks have been developed, and the design of COFs with high adsorption efficiency remains a challenge. Here, a covalent organic framework (DHTP-TPB COF) decorated with hydroxyl groups was developed for the efficient removal of Pb2+ ions. The DHTP-TPB COF showed excellent performance in adsorbing Pb2+ from aqueous solution. More importantly, DHTP-TPB COF exhibited high selectivity for Pb2+ compared to other competing ions, capturing Pb2+ ions with a removal efficiency of over 96% at pH 4. The results show that the DHTP-TPB COF exhibits excellent adsorption capacity at pH 4 of up to 154.3 mg/g for Pb2+ ions; the value is comparable to many previously reported COFs. Moreover, the adsorbed Pb2+ ions could be easily eluted with a 0.1 M EDTA solution, and the DHTP-TPB COF can be reused for more than five adsorption-desorption cycles without significant loss of adsorption capacity. Moreover, the adsorption mechanism was revealed using XPS analysis, indicating the formation of strong coordination-bonding interactions between hydroxyl and Pb2+ ions. Therefore, the DHTP-TPB COF prepared herein has high potential for the treatment of Pb2+-contaminated wastewater and is promising for the adsorption of Pb2+ ions in practical applications.


Asunto(s)
Estructuras Metalorgánicas , Metales Pesados , Contaminantes Químicos del Agua , Plomo , Adsorción , Aguas Residuales , Contaminantes Químicos del Agua/análisis , Metales Pesados/análisis , Iones
5.
Nat Commun ; 13(1): 5460, 2022 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-36115857

RESUMEN

Photocatalytic water splitting is attracting considerable interest because it enables the conversion of solar energy into hydrogen for use as a zero-emission fuel or chemical feedstock. Herein, we present a universal approach for inserting hydrophilic non-conjugated segments into the main-chain of conjugated polymers to produce a series of discontinuously conjugated polymer photocatalysts. Water can effectively be brought into the interior through these hydrophilic non-conjugated segments, resulting in effective water/polymer interfaces inside the bulk discontinuously conjugated polymers in both thin-film and solution. Discontinuously conjugated polymer with 10 mol% hexaethylene glycol-based hydrophilic segments achieves an apparent quantum yield of 17.82% under 460 nm monochromatic light irradiation in solution and a hydrogen evolution rate of 16.8 mmol m-2 h-1 in thin-film. Molecular dynamics simulations show a trend similar to that in experiments, corroborating that main-chain engineering increases the possibility of a water/polymer interaction. By introducing non-conjugated hydrophilic segments, the effective conjugation length is not altered, allowing discontinuously conjugated polymers to remain efficient photocatalysis.

6.
BMC Anesthesiol ; 22(1): 189, 2022 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-35717148

RESUMEN

BACKGROUND: Pain control following breast surgery is of utmost importance in order to reduce the chance of chronic pain development, and facilitate early rehabilitation. The erector spinae plane block (ESPB) is a recently developed regional anaesthesia procedure successfully used for different types of surgical procedures including thoracic and abdominal surgeries. METHODS: A double-blind, randomized, controlled trial was conducted on 90 patients who were scheduled for modified radical mastectomy (MRM). Patients were randomly categorized into groups I (women who underwent ESPB), II (women who underwent paravertebral block (PVB), and III (women who underwent general anaesthesia). RESULTS: The ESPB (4.9 ± 1.2 mg) and PVB (5.8 ± 1.3 mg) groups had significantly lower total morphine consumption than the control group had (16.4 ± 3.1 mg; p < 0.001). Notably, patients in the ESPB group had insignificantly lower morphine consumption than those in the PVB group had (p = 0.076). Moreover, patients in the ESPB and PVB groups had a significantly longer time to first required anaesthesia than those in the control group (7.9 ± 1.2 versus 7.5 ± 0.9 versus 2 ± 1.2 h, respectively; p < 0.001). The postoperative visual analog scale scores were lower in the ESPB and PVB groups than in the control group on the first 24 h after the procedure (p < 0.001). CONCLUSION: ESPB and PVB provide effective postoperative analgesia for women undergoing MRM. The ESPB appears to be as effective as the PVB. TRIAL REGISTRATION: The study was registered before the enrolment of the first patient at the Pan African Clinical Trial Registry ( www.pactr.org ) database. Identification number for the registry is (PACTR202008836682092).


Asunto(s)
Neoplasias de la Mama , Bloqueo Nervioso , Analgésicos , Analgésicos Opioides/uso terapéutico , Femenino , Humanos , Mastectomía/métodos , Morfina , Bloqueo Nervioso/métodos , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/prevención & control
7.
ACS Appl Mater Interfaces ; 13(47): 56554-56565, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34783531

RESUMEN

Organic semiconducting polymers exhibited promising photocatalytic behavior for hydrogen (H2) evolution, especially when prepared in the form of polymer dots (Pdots). However, the Pdot structures were formed using common nonconjugated amphiphilic polymers, which have a negative effect on charge transfer between photocatalysts and reactants and are unable to participate in the photocatalytic reaction. This study presents a new strategy for constructing binary Pdot photocatalysts by replacing the nonconjugated amphiphilic polymer typically employed in the preparation of polymer nanoparticles (Pdots) with a low-molecular-weight conjugated polyelectrolyte. The as-prepared polyelectrolyte/hydrophobic polymer-based binary Pdots truly enhance the electron transfer between the Pt cocatalyst and the polymer photocatalyst with good water dispersibility. Moreover, unlike the nonconjugated amphiphilic polymer, the photophysics and mechanism of this photocatalytic system through time-correlated single-photon counting (TCSPC) and transient absorption (TA) measurements confirmed the Förster resonance energy transfer (FRET) between the polyelectrolyte as a donor and the hydrophobic polymer as an acceptor. As a result, the designated binary Pdot photocatalysts significantly enhanced the hydrogen evolution rate (HER) of 43 900 µmol g-1 h-1 (63.5 µmol h-1, at 420 nm) for PTTPA/PFTBTA Pdots under visible-light irradiation.

8.
Chem Commun (Camb) ; 57(90): 11968-11971, 2021 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-34704990

RESUMEN

We report the synthesis of two carbazole-thiophene-based conjugated microporous polymers (Cz-3Th and Cz-4Th CMPs) with different degrees of planarity for photocatalytic hydrogen evolution from water. Depending upon the building linker's planarity, we found that the porous structure, hydrogen-evolution rate, and photocatalytic stability of the resultant CMPs varied.

9.
Ophthalmic Res ; 46(2): 98-102, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21282966

RESUMEN

AIMS: To investigate the levels of endothelin-1 (ET-1) and nitric oxide (NO) in the aqueous humor and plasma of human eyes with different types of glaucoma: primary open-angle glaucoma (POAG) and chronic closed-angle glaucoma (CCAG). METHODS: Patients were classified into 3 groups: group I comprised 35 patients with POAG, group II comprised 25 patients with CCAG, and 30 patients with senile cataract (group III) were used as a control group. Aqueous humor and corresponding plasma were analyzed for ET-1 and NO concentrations by enzyme-linked immunosorbent assay. A Bonferroni correction for multiple comparisons was performed. RESULTS: There was no significant difference in plasma levels of either ET-1 or NO metabolites between the groups studied. ET-1 and NO were significantly elevated in the aqueous humor of patients with CCAG and POAG compared to the corresponding value in patients with cataract (p < 0.001). ET-1 and NO concentrations in the aqueous humor were more marked in CCAG than in POAG. NO levels were correlated with ET-1 in the aqueous humor of patients with glaucoma (p < 0.001). CONCLUSIONS: Increased concentrations of ET-1 and NO in aqueous humor may be useful with POAG and CCAG. In addition, ET-1 and NO may have useful metabolite levels in the aqueous humor of POAG and CCAG patients as a result of glaucoma damage and may not be a cause of it.


Asunto(s)
Humor Acuoso/metabolismo , Endotelina-1/sangre , Glaucoma de Ángulo Cerrado/sangre , Glaucoma de Ángulo Abierto/sangre , Óxido Nítrico/sangre , Anciano , Enfermedad Crónica , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Presión Intraocular , Masculino , Persona de Mediana Edad , Radioinmunoensayo
10.
Cell ; 125(6): 1193-205, 2006 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-16777607

RESUMEN

Transcription regulatory networks consist of physical and functional interactions between transcription factors (TFs) and their target genes. The systematic mapping of TF-target gene interactions has been pioneered in unicellular systems, using "TF-centered" methods (e.g., chromatin immunoprecipitation). However, metazoan systems are less amenable to such methods. Here, we used "gene-centered" high-throughput yeast one-hybrid (Y1H) assays to identify 283 interactions between 72 C. elegans digestive tract gene promoters and 117 proteins. The resulting protein-DNA interaction (PDI) network is highly connected and enriched for TFs that are expressed in the digestive tract. We provide functional annotations for approximately 10% of all worm TFs, many of which were previously uncharacterized, and find ten novel putative TFs, illustrating the power of a gene-centered approach. We provide additional in vivo evidence for multiple PDIs and illustrate how the PDI network provides insights into metazoan differential gene expression at a systems level.


Asunto(s)
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , ADN de Helmintos/metabolismo , Proteínas de Unión al ADN/metabolismo , Animales , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Biología Computacional , Proteínas de Unión al ADN/genética , Sistema Digestivo/metabolismo , Regiones Promotoras Genéticas , Elementos Reguladores de la Transcripción , Saccharomyces cerevisiae/genética , Factores de Transcripción/metabolismo , Transcripción Genética , Técnicas del Sistema de Dos Híbridos
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