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Herein, this work reports an efficient acephate adsorption using chitosan (CS) incorporating varying amounts of magnetite. A co-precipitation methodology was employed for the functionalization of chitosan with iron nanoparticles, using Fe2+ as the sole iron source and with a low energy requirement. The adsorbents were characterized by FTIR, XRD, VSM, and nitrogen porosimetry techniques. The CSâFe3O4 1:1 NPs showed the highest acephate removal percentage (74.96 %) at pH 9 and ambient temperatures. The adsorption process exhibited high dependencies on pH, adsorbent dosage, initial concentration of adsorbate, and ionic strength. Sips and pseudo-second-order kinetics models best adjusted the experimental data, suggesting that the process occurs on a heterogeneous surface. Thermodynamic evaluation showed that the adsorption was exothermic, favorable, and predominately through chemical interactions. Finally, the CSâFe3O4 showed no significant decrease after several cycles of adsorption/desorption, avoiding centrifugation-filtration steps.
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Introduction: Currently, Chronic Obstructive Pulmonary Disease (COPD) has a high impact on morbidity and mortality worldwide. The increase of CD4+, CD8+ cells expressing NF-κB, STAT4, IFN-γ and perforin are related to smoking habit, smoking history, airflow rate, obstruction and pulmonary emphysema. Furthermore, a deficiency in CD4+CD25+Foxp3+ regulatory T cells (Tregs) may impair the normal function of the immune system and lead to respiratory immune disease. On the other hand, the anti-inflammatory cytokine IL-10, produced by Treg cells and macrophages, inhibits the synthesis of several pro-inflammatory cytokines that are expressed in COPD. Therefore, immunotherapeutic strategies, such as Photobiomodulation (PBM), aim to regulate the levels of cytokines, chemokines and transcription factors in COPD. Consequently, the objective of this study was to evaluate CD4+STAT4 and CD4+CD25+Foxp3+ cells as well as the production of CD4+IFN- γ and CD4+CD25+IL-10 in the lung after PBM therapy in a COPD mice model. Methods: We induced COPD in C57BL/6 mice through an orotracheal application of cigarette smoke extract. PMB treatment was applied for the entire 7 weeks and Bronchoalveolar lavage (BAL) and lungs were collected to study production of IFN- γ and IL-10 in the lung. After the last administration with cigarette smoke extract (end of 7 weeks), 24 h later, the animals were euthanized. One-way ANOVA followed by NewmanKeuls test were used for statistical analysis with significance levels adjusted to 5% (p < 0.05). Results: This result showed that PBM improves COPD symptomatology, reducing the number of inflammatory cells (macrophages, neutrophils and lymphocytes), the levels of IFN-γ among others, and increased IL-10. We also observed a decrease of collagen, mucus, bronchoconstriction index, alveolar enlargement, CD4+, CD8+, CD4+STAT4+, and CD4+IFN-γ+ cells. In addition, in the treated group, we found an increase in CD4+CD25+Foxp3+ and CD4+IL-10+ T cells. Conclusion: This study suggests that PBM treatment could be applied as an immunotherapeutic strategy for COPD.
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2,4-Dichlorophenoxyacetic acid (2,4-D) is an herbicide and is among the most widely distributed pollutant in the environment and wastewater. Herein is presented a complete comparison of adsorption performance between two different magnetic carbon nanomaterials: graphene oxide (GO) and its reduced form (rGO). Magnetic functionalization was performed employing a coprecipitation method, using only one source of Fe2+, requiring low energy, and potentially allowing the control of the amount of incorporated magnetite. For the first time in literature, a green reduction approach for GO with and without Fe3O4, maintaining the magnetic behavior after the reaction, and an adsorption performance comparison between both carbon nanomaterials are demonstrated. The nanoadsorbents were characterized by FTIR, XRD, Raman, VSM, XPS, and SEM analyses, which demonstrates the successful synthesis of graphene derivate, with different amounts of incorporate magnetite, resulting in distinct magnetization values. The reduction was confirmed by XPS and FTIR techniques. The type of adsorbent reveals that the amount of magnetite on nanomaterial surfaces has significant influence on adsorption capacity and removal efficiency. The procedure demonstrated that the best performance, for magnetic nanocomposites, was obtained by GOâFe3O4 1:1 and rGOâFe3O4 1:1, presenting values of removal percentage of 70.49 and 91.19%, respectively. The highest adsorption capacity was reached at pH 2.0 for GOâFe3O4 1:1 (69.98 mg g-1) and rGOâFe3O4 1:1 (89.27 mg g-1), through different interactions: π-π, cation-π, and hydrogen bonds. The adsorption phenomenon exhibited a high dependence on pH, initial concentration of adsorbate, and coexisting ions. Sips and PSO models demonstrate the best adjustment for experimental data, suggesting a heterogeneous surface and different energy sites, respectively. The thermodynamic parameters showed that the process was spontaneous and exothermic. Finally, the nanoadsorbents demonstrated a high efficiency in 2,4-D adsorption even after five adsorption/desorption cycles.
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Grafito , Herbicidas , Nanocompuestos , Contaminantes Químicos del Agua , Adsorción , Herbicidas/análisis , Grafito/química , Óxido Ferrosoférrico , Agua/química , Nanocompuestos/química , Fenómenos Magnéticos , Ácido 2,4-Diclorofenoxiacético , Cinética , Contaminantes Químicos del Agua/análisis , Concentración de Iones de HidrógenoRESUMEN
Several medicinal plants have been administered to cancer patients attributed to their anticarcinogenic and chemoprotective properties, in addition to lower toxicity compared to traditional therapies. The aim was to investigate the antioxidant properties and carotenoid composition of aqueous extracts of Mentha piperita or Artemisia vulgaris which were previously found to exert beneficial effects on human health through diet. aqueous extracts exhibited potent antioxidant activity. A diversity of carotenoids was identified in these extracts using HPLC-PDA-MS/MS. Both extracts contained predominantly all-trans-lutein as the main component within this class. In order to investigate antioxidant properties, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) techniques were used. The (3-4,5 dimethylthiazol-2, 5 diphenyl tetrazolium bromide) (MTT) and Crystal Violet assays assessed cellular cytotoxicity. Assessments of presence of reactive species were carried out following exposure of oral squamous cell carcinoma cell line (SCC-4) to various aqueous extracts of M piperita or A vulgaris utilizing dichlorofluorescein diacetate (DCFH-DA) and nitric oxide (NO) assays. Exposure to these extracts induced severe cytotoxic effects, which led to investigation of the biochemical and molecular mechanisms underlying this observed effect. Data demonstrated that both solutions induced oxidative stress and DNA damage, especially at higher concentrations using agarose gel subjected to electrophoresis. It is known that exposure to excess amounts of antioxidants results in a prooxidant effect which is beneficial in cancer therapy. Further, the extracts were found to reduce viability of SCC-4 in culture, indicating that this antitumoral activity may be of therapeutic importance and requires further study.
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Artemisia , Carcinoma de Células Escamosas , Neoplasias de la Boca , Humanos , Antioxidantes/farmacología , Antioxidantes/química , Mentha piperita/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Espectrometría de Masas en Tándem , División del ADN , Fitoquímicos , Carotenoides/farmacologíaRESUMEN
Among biotic and abiotic stresses, the most restrictive for plant distribution is salt stress, where different concentrations might exert harmful effects on seed germination. Recently, nanomaterials were used successfully to mitigate these stresses, indicating that plants may be able to develop normally in adverse conditions. The aim of this study was to examine the effects of graphene oxide (GO) on the germination of Persian clover seedlings under salt stress conditions. Following sown on substrate paper, seeds were tested after exposure to different concentrations of graphene oxide (0, 125, 250, or 500 mg L-1 GO), sodium chloride (0; -0.1; -0.2; -0.3, or -0.4 MPa NaCl) and/or GO + salt concomitantly, and then stored for 7 days in a germination chamber at 20°C in the presence of light. Seed germination and growth parameters of seedlings were determined. Graphene oxide demonstrated protective effect against salt stress as evident by no marked adverse effects on seed germination where GO blocked the salt-induced reduction in germination. The results obtained provide references for the safe application of nanomaterials and emphasize the significance of GO as a promising material for reducing the toxicity of salts in agriculture.
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Germinación , Semillas , Estrés Salino , PlantonesRESUMEN
Renal neoplasms are highlighted as one of the 10 most common types of cancer. Renal cell carcinoma (RCC) is the most common type of renal cancer, considered the seventh most common type of cancer in the Western world. The most frequently altered genes described as altered are VHL, PBRM1, SETD2, KDM5C, PTEN, BAP1, mTOR, TP53, TCEB1 (ELOC), SMARCA4, ARID1A, and PIK3CA. RCC therapies can be classified in three groups: monoclonal antibodies, tyrosine kinase inhibitors, and mTOR inhibitors. Besides, there are targeted agents to treat RCC. However, frequently patients present side effects and resistance. Even though many multidrug resistance mechanisms already have been reported to RCC, studies focused on revealing new biomarkers as well as more effective antitumor therapies with no or low side effects are very important. Some studies reported that natural products, such as honey, epigallocatechin-3-gallate (EGCG), curcumin, resveratrol, and englerin A showed antitumor activity against RCC. Moreover, nanoscience is another strategy to improve RCC treatment and reduce the side effects due to the improvement in pharmacokinetics and reduction of toxicities of chemotherapies. Taking this into account, we conducted a systemic review of recent research findings on RCC hallmarks, drug resistance, and adjuvant therapies. In conclusion, a range of studies reported that RCC is characterized by high incidence and increased mortality rates because of the development of resistance to standard therapies. Given the importance of improving RCC treatment and reducing adverse effects, nanoscience and natural products can be included in therapeutic strategies.
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The particular plant species found in southern Brazil, Vassobia breviflora (Solanaceae) has only a few apparent studies examining its biological effect. Thus, the aim of the present study was to determine the activity of the acetone extract fraction derived from V. breviflora. Four compounds were identified by ESI-qTOF-MS: eucalrobusone R, aplanoic acid B, pheophorbide A, and pheophytin A. In addition, 5 compounds were identified by HPLC-PDA-MS/MS: all-trans-lutein, 15-cis-lutein, all-trans-ß-carotene, 5,8-epoxy-ß-carotene, and cis-ß-carotene. Cell lines A549 (lung cancer), A375 (melanoma cancer) and HeLa (cervical cancer) were incubated with different concentrations of each studied extract using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), lactate dehydrogenase (LDH), and 2'-7'dichlorofluorescin diacetate (DCFH-DA) assays. The acetonic extract exhibited cytotoxic activity at a concentration of 0.03 mg/ml in the HeLa strain and 0.1 mg/ml in the others. In addition to increased production of reactive oxygen species (ROS). Antibacterial activity was assessed utilizing minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) in 9 ATCCs strains and 7 clinical isolates, as well as determination of biofilm production. Data demonstrated that MIC and MBC were approximately 256 mg/ml in most of the strains tested and antibiofilm effect at S. aureus, S. epidermidis, A. baumannii, and E. faecalis, concentrations below the MIC. Genotoxic activity on plasmid DNA did not produce significant elevated levels in breaks in the isolated genetic material.
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Acetona , Luteína , Staphylococcus aureus , Espectrometría de Masas en Tándem , beta Caroteno , BrasilRESUMEN
Due to its wide use in anticonvulsant pharmacotherapy, phenobarbital (PHEN) is an aquatic contaminant with a high prevalence in the environment. In this adsorption study, chitosan and chitosan-based magnetic adsorbents containing different amounts of incorporated magnetite (CS, CS·Fe3O4 1:1, CS·Fe3O4 1:5, and CS·Fe3O4 1:10) were used for phenobarbital removal. The magnetic adsorbents were synthesized by co-precipitation method and characterized through FTIR, XRD, MEV, and VSM analysis. In PHEN adsorption, the equilibrium and adsorption kinetic were better adjusted by the Sips and pseudo-second-order model, respectively. Among the four nanoadsorbents used, the maximum phenobarbital adsorption capacity was 94.60 mg g-1 using 25 mg of CS·Fe3O4 1:5, with a concentration of PHEN (50 mg L-1), pH 7.0 at room temperature. The parameters of pH, adsorbent dosage, ionic strength, and thermodynamic study were tested for the adsorbent with the highest performance (CS·Fe3O4 1:5). The nanoadsorbent demonstrates efficiency in the removal of the contaminant for diverse adsorption cycles. Finally, the protocol employing magnetic adsorbents dispenses the subsequent steps of filtration and centrifugation.
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Quitosano , Contaminantes Químicos del Agua , Purificación del Agua , Quitosano/química , Óxido Ferrosoférrico/química , Concentración de Iones de Hidrógeno , Termodinámica , Adsorción , Agua/química , Cinética , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , FenobarbitalRESUMEN
Vassobia breviflora (Sendtn.) Hunz is a plant of the Solanaceae family from South America and there are no apparent studies reported on the biological activity of the hexane extract. The aim of this investigation was to conduct phytochemical analyses using ESI-TOF-MS, while antioxidant activities were evaluated by the following methods 1,1-diphenyl-2-picrylhydrazyl (DPPH) 2,2"-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) radical capture (ABTS), ferric reducing antioxidant power (FRAP), total antioxidant capacity (TAC), and total oxidant status (TOS). Antimicrobial activities were performed by determining the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and antibiofilm formed. Cytotoxicity was measured by MTT and dsDNA PicoGreen tests, beyond the production of reactive oxygen species (ROS) determined by Dichlorodihydrofluorescein diacetate (DCFH-DA). The hexane extract showed the presence of 5 (choline, pantothenic acid, calystegine B, lanciphodylactone I, and 15"-cis-zeaxanthin) compounds detected. V. breviflora extract demonstrated reliable results utilizing different antioxidant methods. In antibacterial activity, V. breviflora extract exhibited inhibitory, bactericidal, and antibiofilm action in biofilm-forming bacteria. The hexane extract exhibited cytotoxicity against melanoma, lung cancer, glioblastoma, leukemia, uterine colon, and hepatocarcinoma tumor cells. In addition, all tested strains resulted in increased production of ROS. This plant extract may be considered in future as an alternative for development of new therapeutic options aimed at the treatment of diverse pathologies.
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Antioxidantes , Solanaceae , Antioxidantes/farmacología , Antioxidantes/química , Especies Reactivas de Oxígeno , Hexanos , Antibacterianos/farmacología , Extractos Vegetales/farmacología , Extractos Vegetales/química , Fitoquímicos/farmacologíaRESUMEN
Herein, tetracycline adsorption employing magnetic chitosan (CS·Fe3O4) as the adsorbent is reported. The magnetic adsorbent was synthesized by the co-precipitation method and characterized through FTIR, XRD, SEM, and VSM analyses. The experimental data showed that the highest maximum adsorption capacity was reached at pH 7.0 (211.21 mg g-1). The efficiency of the magnetic adsorbent in tetracycline removal was dependent on the pH, initial concentration of adsorbate, and the adsorbent dosage. Additionally, the ionic strength showed a significant effect on the process. The equilibrium and kinetics studies demonstrate that Sips and Elovich models showed the best adjustment for experimental data, suggesting that the adsorption occurs in a heterogeneous surface and predominantly by chemical mechanisms. The experimental results suggest that tetracycline adsorption is mainly governed by the hydrogen bonds and cation-π interactions due to its pH dependence as well as the enhancement in the removal efficiency with the magnetite incorporation on the chitosan surface, respectively. Thermodynamic parameters indicate a spontaneous and exothermic process. Finally, magnetic chitosan proves to be efficient in TC removal even after several adsorption/desorption cycles.
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Delayed fluorescence (DF) by triplet-triplet annihilation (TTA) is observed in solutions of a benzoperylene-imidoester mesogen that shows a hexagonal columnar mesophase at room temperature in the neat state. A similar benzoperylene-imide with a slightly smaller HOMO-LUMO gap, that also is hexagonal columnar liquid crystalline at room temperature, does not show DF in solution, and mixtures of the two mesogens show no DF in solution either, because of collisional quenching of the excited triplet states on the imidoester by the imide. In contrast, DF by TTA from the imide but not from the imidoester is observed in condensed films of such mixtures, even though neat films of either single material are not displaying DF. In contrast to the DF from the monomeric imidoester in solution, DF of the imide occurs from dimeric aggregates in the blend films, assisted by the imidoester. Thus, the close contact of intimately stacked molecules of the two different species in the columnar mesophase leads to a unique mesophase-assisted aggregate DF. This constitutes the first observation of DF by TTA from the columnar liquid crystalline state. If the imide is dispersed in films of polybromostyrene, which provides an external heavy-atom effect facilitating triplet formation, DF is also observed. Organic light-emitting diodes (OLEDs) devices incorporating these liquid crystal molecules demonstrated high external quantum efficiency (EQE). On the basis of the literature and to the best of our knowledge, the EQE reported is the highest among nondoped solution-processed OLED devices using a columnar liquid crystal molecule as the emitting layer.
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Emerging pollutants are a group of substances involved in environmental contamination resulting mostly from incomplete drug metabolism, associated with inadequate disposal and ineffective effluent treatment techniques. Methotrexate (MTX), for instance, is excreted at high concentrations in unchanged form through the urine. Although the MTX is still effective in cancer and autoimmune disease treatment, this drug shows the ability of bioaccumulation and toxicity to the organism. Thus, the present work aimed to evaluate the adsorption of the MTX drug onto magnetic nanocomposites containing different amounts of incorporated magnetite (1:1, 1:5, and 1:10 wt%), combining the theoretical-experimental study as well as the in vitro cytotoxicity. Moreover, equilibrium studies (Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, Hill, Redlich-Peterson, and Sips), kinetic (PFO, PSO, and IPD), and thermodynamic (ΔG°, ΔH°, and ΔS°) were used to describe the experimental data, and ab initio simulations were employed in the theoretical study. Magnetic nanocomposites were synthesized by the co-precipitation method using only FeCl2 as the iron precursor. Adsorbents were characterized by FTIR, XRD, Raman, SEM-EDS, BET, and VSM analysis. Meanwhile, cytotoxic effects on L929 and A375 cell lines were evaluated through MTT, NR, and LDH assays. The adsorption of the MTX was carried out in a typical batch system, exploring the different experimental conditions. The theoretical study suggests the occurrence of chemisorption between CS·Fe3O4-MTX. The maximum adsorption capacity of MTX was 285.92 mg g-1, using 0.125 g L-1 of CS·Fe3O4 1:1, with an initial concentration of the MTX (50 mg L-1), pH 4.0 at 293 ± 1.00 K. The best adjustment of equilibrium and kinetic data were the Sips (low values for statistical errors) and PSO (qe = 96.73 mg g-1) models, respectively. Thermodynamic study shows that the adsorption occurred spontaneously (ΔG° < 0), with exothermic (ΔH° = - 4698.89 kJ mol-1) and random at the solid-solution interface (ΔS° = 1,476,022.00 kJ mol-1 k-1) behavior. Finally, the in vitro study shows that magnetic nanomaterials exhibit higher cytotoxicity in melanoma cells. Therefore, the magnetic nanocomposite reveals to be not only an excellent tool for water remediation studies but also a promising platform for drug delivery.
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Quitosano , Contaminantes Químicos del Agua , Adsorción , Óxido Ferrosoférrico , Concentración de Iones de Hidrógeno , Hierro/análisis , Cinética , Metotrexato/análisis , Temperatura , Termodinámica , Agua , Contaminantes Químicos del Agua/análisisRESUMEN
The pollution of wastewater with dyes has become a serious environmental problem around the world. In this context, the work aims to synthesize and characterize a supported nanocatalyst (NZ-180) from rice husk (RH) and alum sludge (AS) incorporating silver (AgNPs@NZ-180) and titanium nanoparticles (TiNPs@NZ-180) for Rhodamine B (RhB) dye degradation, under UV and visible irradiation. Central rotatable composite design (CRCD) was used to determine ideal conditions, using nanocatalyst and dye concentration such as input variables and degradation percentage like response variable. Samples were characterized by XRD, SEM-EDS, N2 porosimetry, DLS, and zeta potential analyses. TiNPs@NZ-180 showed the best photocatalytic activity (62.62 and 50.82% under UV and visible irradiation, respectively). Specific surface area has increased from 35.90 to 418.90 m2 g-1 for NZ-180 and TiNPs@NZ-180, respectively. Photocatalytic performance of TiNPs@NZ-180 has reduced to 8 and 10% after 5 cycles under UV and visible light irradiation. Ideal conditions found by CRCD were 2.75 g L-1 and 20 mg L-1 for nanocatalyst and RhB concentrations, respectively. Therefore, (agro)industrial waste present such an alternative material for application in the removal of wastewater with dyes, which helps in the reduction of the impact of chemicals/pollutants on human and animal health.
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Residuos Industriales , Plata , Animales , Catálisis , Colorantes , Humanos , Luz , Titanio , Aguas ResidualesRESUMEN
It is largely known that photobiomodulation (PBM) has beneficial effects on allergic pulmonary inflammation. Our previous study showed an anti-inflammatory effect of the PBM in an acute experimental model of asthma, and we see that this mechanism is partly dependent on IL-10. However, it remains unclear whether the activation of regulatory T cells is mediated by PBM in a chronic experimental model of asthma. In this sense, the objective of this study was to verify the anti-inflammatory role of the PBM in the pulmonary inflammatory response in a chronic experimental asthma model. The protocol used for asthma induction was the administration of OVA subcutaneously (days 0 and 14) and intranasally (3 times/week, for 5 weeks). On day 50, the animals were sacrificed for the evaluation of the different parameters. The PBM used was the diode, with a wavelength of 660 nm, a power of 100 mW, and 5 J for 50 s/point, in three different application points. Our results showed that PBM decreases macrophages, neutrophils, and lymphocytes in the bronchoalveolar lavage fluid (BALF). Moreover, PBM decreased the release of cytokines by the lung, mucus, and collagen in the airways and pulmonary mechanics. When we analyzed the percentage of Treg cells in the group irradiated with laser, we verified an increase in these cells, as well as the release of IL-10 in the BALF. Therefore, we conclude that the use of PBM therapy in chronic airway inflammation attenuated the inflammatory process, as well as the pulmonary functional and structural parameters, probably due to an increase in Treg cells.
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Asma , Interleucina-10 , Terapia por Luz de Baja Intensidad , Animales , Antiinflamatorios/farmacología , Asma/tratamiento farmacológico , Asma/radioterapia , Linfocitos T CD4-Positivos , Modelos Animales de Enfermedad , Factores de Transcripción Forkhead , Inflamación , Interleucina-10/metabolismo , Pulmón , Ratones , Ratones Endogámicos BALB C , OvalbúminaRESUMEN
Background Anemia is a clinical condition frequently seen in patients with inflammatory bowel disease, which is responsible for a significant loss of quality of life. Objective To assess the efficacy and safety of using oral liposomal iron to treat iron deficiency anemia in inflammatory bowel disease patients, as well as assess the impact of this treatment on psychometric scores. Methods Patients with inactive/mildly active inflammatory bowel disease were screened for anemia in this interventional pilot study conducted from November 2016 to March 2018. Patients with mild anemia were treated with oral liposomal iron for 8 weeks. Main outcome measure The primary endpoint of the study was the response to liposomal oral iron therapy. Treatment response was defined as patients who achieved a hemoglobin increase of ≥ 1 g/dL and/or hemoglobin normalization by the 8th week of treatment. Results Out of 200 screened patients, 40 (20%) had anemia. Of the 21 patients who completed treatment, 13 (62%) responded to oral liposomal iron replacement therapy (mean increases of hemoglobin from 11.4 to 12.6 g/dL). The transferrin saturation index increased by an average of 10.2 (p = 0.006) and the quality of life by 26.3 (p < 0.0001). There was also a mean reduction of 9.2 in the perception of fatigue (p < 0.0001). Conclusion Treatment with oral liposomal iron is effective in improving mild iron deficiency anemia and quality of life, as well as in decreasing fatigue in patients with inactive or mildly active inflammatory bowel disease.
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Anemia Ferropénica/tratamiento farmacológico , Anemia Ferropénica/etiología , Difosfatos/uso terapéutico , Enfermedades Inflamatorias del Intestino/complicaciones , Hierro/uso terapéutico , Calidad de Vida , Adolescente , Adulto , Difosfatos/administración & dosificación , Difosfatos/efectos adversos , Portadores de Fármacos , Fatiga/tratamiento farmacológico , Fatiga/etiología , Femenino , Hemoglobinas/análisis , Humanos , Hierro/administración & dosificación , Hierro/efectos adversos , Liposomas , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Transferrina/análisis , Adulto JovenRESUMEN
Dibenzo[a,j]coronene-tetracarboxylic alkyl esters and imides with either a centrosymmetric bis-peri substitution pattern or a polar bis-ortho substitution pattern form hexagonal columnar mesophases, which in the case of the imides persist at room temperature. The bis-peri isomers are obtained via a two-fold oxidative photocyclization; the bis-ortho isomers are accessed via a glyoxylic Perkin reaction of triphenylene and naphthalene building blocks. Steric congestion between the substituents and the adjacent benzo protrusion in the bis-ortho esters and imides leads to bending of the aromatic plane, which thus avoids twisting. These isomers surprisingly show a more pronounced liquid crystalline behaviour than their non-bent bis-peri homologs, accommodating non-planarity with columnar order by slipped stacking. Whereas both types of ester and the bis-peri imide show an optical behaviour typical for perylene chromophores, the strongly bent bis-ortho imide distinguishes itself notably from them by its absorption spectrum. The electron acceptor strength of the isomeric diimides is found to differ, the hexagonal (peri) diimide having a 0.20â eV lower LUMO energy than the pentagonal (ortho) isomer.
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The photocyclization of tetraethyl 1,4-phenylenebis(phenylmaleate) in the presence of iodine and oxygen predominantly yields tetraethyl [5]helicene-5,6,9,10-tetracarboxylate, together with small amounts of tetraethyl dibenz[a,h]anthracene-5,6,12,13-tetracarboxylate and tetraethyl benzo[ghi]perylene-3,4,11,12-tetracarboxylate. The helicene tetraester is planarized to the benzoperylene tetraester by Scholl reaction with AlCl3 followed by reesterification of the partially hydrolyzed crude product. Subsequent treatment with a branched alkylamine yields a columnar liquid-crystalline benzoperylene diimide whose mesophase is stable at room temperature despite its limited and non-centrosymmetric alkyl periphery. Its absorption spectrum is markedly red-shifted compared to that of a similar benzoperylene triimide.
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The twofold glyoxylic Perkin reaction of perylene-3,9-diglyoxylic acid with thiophene-diacetic acid followed by oxidative photocylization and reaction with α-branched primary alkylamines yields columnar liquid-crystalline diimides with two sulfur atoms in the condensed arene system. A broad temperature range of the hexagonal columnar mesophase is induced by racemic doubly branched alkyl chains. The HOMO and LUMO energy levels of these thiophene-derived diimides qualify them as electron donors with respect to perylene diimides.
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Whereas perylene tetracarboxdiimides derived from amino-n-alkanes if at all only show monotropic (thermodynamically unstable) mesogenic self-assembly, the hexagonal columnar liquid crystalline state can be stabilized over a broad temperature range with doubly branched, doubly racemic alkyl residues. An improved tendency to homeotropic surface orientation is observed, and the orientation of the liquid crystalline domains is maintained upon cycling through the crystalline state at room temperature.
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UNLABELLED: Anemia is common in inflammatory bowel disease (IBD). However, epidemiological studies of nonwestern IBD populations are limited and may be confounded by demographic, socioeconomic, and disease-related influences. This study evaluated the prevalence, risk factors, and etiology of anemia in Brazilian outpatients with IBD. METHODS: In this cross-sectional study, 100 Crohn's disease (CD) patients and 100 ulcerative colitis (UC) subjects were assessed. Anemia workup included complete blood count, ferritin, transferrin saturation, serum levels of folic acid and vitamin B12, and C-reactive protein (CRP) concentration. RESULTS: The overall prevalence of anemia in IBD was 21%. There was no significant difference in the prevalence of anemia between CD subjects (24%) and UC (18%). Moderate disease activity (OR: 3.48, 95% CI, 1.95-9.64, P = 0.002) and elevated CRP levels (OR: 1.8, 95% CI, 1.04-3.11, P = 0.02) were independently associated with anemia. The most common etiologies of anemia found in both groups were iron deficiency anemia (IDA; 10% on CD and 6% on UC) followed by the anemia of chronic disease (ACD; 6% for both groups). CONCLUSIONS: In Brazilian IBD outpatients, anemia is highly concurrent condition. Disease moderate activity as well as increased CRP was strongly associated with comorbid anemia. IDA and/or ACD were the most common etiologies.