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1.
Environ Monit Assess ; 195(11): 1378, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37882833

RESUMO

In the proposed research, a lanthanum-doped metal-organic framework (La-ATP) has been synthesised to remove phosphate from contaminated aqueous solutions. La-ATP was synthesised by a green energy-saving route using microwave irradiation and exhibited a phenomenal sorption capacity of 290 mg/g for the removal of phosphate. At a minimal dose of 0.1 g/L, 25 mg/L of phosphate gets reduced to 6.3 mg/L within 5 min and reaches equilibrium in 25 min. The isoelectric point of La-ATP was found to be 8.99, and it is efficient in removing phosphate over a wide range of pH 5-10. The existence of commonly occurring competing anions like sulphate, fluoride, chloride, arsenate, bicarbonate, and nitrate does not affect the uptake capacity of La-ATP towards phosphate ions. Furthermore, the robustness of La-ATP is demonstrated by its applicability to remove phosphate from real-life sewage water by reducing 10 mg/L of phosphorus from sewage water to < 0.02 mg/L. The primary mechanism governing phosphate removal was found to be ionic interaction and ligand exchange. Therefore, La-ATP can be considered a viable candidate for the treatment of eutrophic water streams because of its high sorption capacity, super-fast kinetics, and adaptability to contaminated sewage.


Assuntos
Estruturas Metalorgânicas , Fosfatos , Esgotos , Monitoramento Ambiental , Trifosfato de Adenosina
2.
Int J Chron Obstruct Pulmon Dis ; 17: 1751-1768, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35965841

RESUMO

Purpose: This qualitative study explored patients' attitudes about and perceptions of generic dry powder inhaler (DPI) substitution for the brand product and patients' views of generic product quality, efficacy, design, and usability. Methods: Forty COPD and asthma patients (36 adults, four adolescents), who were actively using a brand DPI product, participated in one of six focus groups. Participants completed a journey mapping exercise to assess attitudes and opinions about a scenario where they refill their prescription and unexpectedly receive a generic DPI instead of their brand DPI. The focus groups were audio recorded, transcribed, and analyzed thematically. Results: The hypothetical scenario of unexpectedly receiving a generic DPI elicited mixed feelings including: happiness and relief about potential cost savings, confusion, disappointment, anger, and/or frustration with the unexpected switch. Participants in most groups anticipated anxiety or hesitation in using the generic DPI due to concerns about potential differences in usability, uncertainty about correct use, and questions about efficacy. Participants across all groups said they would ask a pharmacist or healthcare provider for information or answers to their questions, and some participants said they would use online resources. When participants held the brand and generic DPI devices, most preferred the brand DPI device and found it easier, less cumbersome, or more convenient to use (due to size and weight). However, many participants reiterated that the potential reduced cost of the generic DPI would be a primary factor in their decision-making related to generic DPI substitution for their brand DPI. Conclusion: Patients experienced a mixture of positive and negative feelings when faced with an unexpected generic DPI substitution. Some patients have doubts about their ability to successfully navigate differences in generic device design, and most expressed the desire to participate in discussions and decision-making with their HCP about generic DPI sameness and substitution.


Assuntos
Inaladores de Pó Seco , Doença Pulmonar Obstrutiva Crônica , Administração por Inalação , Adolescente , Adulto , Medicamentos Genéricos/uso terapêutico , Humanos , Pós/uso terapêutico , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico
3.
Chemosphere ; 270: 129490, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33418227

RESUMO

A novel MOF based adsorbent was prepared by functionalization of MIL 88A with mercapto ethanol to yield MIL88A-SH and evaluated for the removal of Hg(II) in water and Hg(0) in air. The prepared MOFs were characterized by field emission scanning electron microscope (FESEM), Transmission electron microscopy (TEM), Brunauer- Emmett-Teller (BET), Fourier transform infrared spectroscopy (FTIR), and zeta X-ray photoelectron microscopy (XPS). The reaction rate was found to be very fast and within 15 min 95.5% Hg(II) was removed. The kinetics data followed pseudo second order model with rate constant values at 1.19 and 2.38 g/µg/min for MIl88A and MIL88A-SH respectively. A very high adsorption capacity in the order 1111.1 mg/g of Hg(II) was found using MIL88A-SH as adsorbent. The uptake was found to be constant in a wide range of pH from 5 to 9. Furthermore, in the presence other interfering metal ions, viz., Cu(II), As(V), Cd(II), Cr(VI), Pb(II), Zn(II), MIL88A-SH demonstrated an excellent adsorption for Hg(II). Around 45.6 mg/g of Hg(0) was found to be adsorbed by MIL88A-SH. XPS, FTIR and XRD studies suggested insitu oxidation Hg(0) to Hg(II) and complexation of Hg(II) with thiol groups during adsorption. Applicability on removal of Hg(II) at ppb levels from drinking water, fast kinetics, wide pH range, a very high sorption capacity, Hg(0) removal, selectivity and recyclability makes MIL88A-SH an efficient adsorbent to tackle mercury contamination.


Assuntos
Mercúrio , Estruturas Metalorgânicas , Poluentes Químicos da Água , Purificação da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Int J Biol Macromol ; 151: 713-722, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32088223

RESUMO

Biological macromolecule namely cellulose nanofiber was synthesized from agrowaste sugarcane bagasse. Further, hierarchical nano Fe(0) - FeS was anchored on cellulose nanofibers to obtain CNF-Fe(0)@FeS and it was characterized by various spectral techniques. Formation of FeS2 was confirmed by high resolution TEM and XPS techniques. Anchoring on cellulose nano fibers prevented agglomeration of nanocomposite and furthermore, coating of FeS2 helped in the preservation of Fe(0). Thus the prepared nano composite was very effective in the removal of cationic Methylene blue (MB) dye and anionic Congo red (CR) dye with a maximum adsorption capacity of 200.0 and 111.1 mg/g respectively. Both MB and CR dye followed Pseudo second kinetic with regression coefficients >0.98. Especially for MB dye, it was observed that kinetics of adsorption/degradation was very fast and within 3 min, peak at 370 nm disappeared and 70% reduction in intensity was observed at 660 nm. Further FTIR and XPS revealed evidence for the degradation of adsorbed dye molecules. Considering its high adsorption capacity, degradation potential and ease of preparation using agrowaste makes CNF-Fe(0)@FeS a promising sorbent for the treatment industrial dye effluents.


Assuntos
Celulose/química , Compostos Férricos/química , Compostos Ferrosos/química , Nanofibras/química , Adsorção , Corantes , Cinética , Azul de Metileno , Nanocompostos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
5.
Sci Rep ; 9(1): 12639, 2019 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477772

RESUMO

Green environment friendly and novel nano MgS decorated cellulose nanofibres (MgS@CNF) were prepared, characterized and evaluated towards the removal of heavy metal namely, cadmium from aqueous solutions. Cellulose nanofibres acted as a template for effective dispersion of MgS nanoparticles and also aid in the complexation of cadmium ions. In depth X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and Fourier transform infra red spectroscopy (FTIR) studies revealed that doped MgS on mild acidification yields insitu production of H2S which effectively complexes cadmium ion to form cadmium sulfide. The reaction followed pseudo first order kinetics with regression coefficient in the order of 0.98. A very high Langmuir adsorption capacity in the order of 333.33 mg/g was obtained for MgS@CNF. Finally, MgS@CNF was applied towards the removal of cadmium from organic and TDS rich tannery waste water. MgS@CNF was effective in bringing down the concentration from ppm to ppb levels.

6.
Int J Biol Macromol ; 128: 556-565, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30708010

RESUMO

Cellulose nanofibers were extracted from sugarcane bagasse. Zerovalent­iron (ZVI)/Zirconium(IV) (Zr)/ZVI-Zr doped cellulose nanofibers were prepared, characterized and evaluated for fluoride removal. The prepared nanofibers could effectively remove fluoride within a wide pH range of 3.0 to 8.0. The equilibrium reached within 3 h and the adsorption capacities followed the order ZrZVICNF > ZrCNF > ZVICNF. The Langmuir adsorption capacity of ZrZVICNF was 35.70 mg/g, much higher than various commercial adsorbents. Nitrate, chloride, sulphate, phosphate, has insignificant effect on fluoride adsorption and higher concentrations of bicarbonate and silicate ions affected fluoride sorption. Furthermore insignificant amount of Zr(IV) ions were leached during adsorption owing to its efficient complexation with hydroxyl groups of cellulose and the adsorbent could be successfully regenerated. Spectroscopic analysis revealed that fluoride ion complexed with both Zr(IV) and Fe(II)/Fe(III) ions. Thus high fluoride uptake capacity, faster kinetics, applicability at wide pH range, makes ZrZVICNF as attractive sorbent for defluoridation.


Assuntos
Agricultura , Celulose/química , Fluoretos/isolamento & purificação , Ferro/química , Nanofibras/química , Resíduos , Zircônio/química , Adsorção , Fluoretos/química , Concentração de Íons de Hidrogênio , Cinética , Purificação da Água
7.
Front Immunol ; 10: 1027, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31139184

RESUMO

Management of pain in the treatment of rheumatoid arthritis (RA) is a priority that is not fully addressed by the conventional therapies. In the present study, we evaluated the efficacy of cannabinoid receptor 2 (CB2) agonist JWH-015 using RA synovial fibroblasts (RASFs) obtained from patients diagnosed with RA and in a rat adjuvant-induced arthritis (AIA) model of RA. Pretreatment of human RASFs with JWH-015 (10-20 µM) markedly inhibited the ability of pro-inflammatory cytokine interleukin-1ß (IL-1ß) to induce production of IL-6 and IL-8 and cellular expression of inflammatory cyclooxygenase-2 (COX-2). JWH-015 was effective in reducing IL-1ß-induced phosphorylation of TAK1 (Thr184/187) and JNK/SAPK in human RASFs. While the knockdown of CB2 in RASFs using siRNA method reduced IL-1ß-induced inflammation, JWH-015 was still effective in eliciting its anti-inflammatory effects despite the absence of CB2, suggesting the role of non-canonical or an off-target receptor. Computational studies using molecular docking and molecular dynamics simulations showed that JWH-105 favorably binds to glucocorticoid receptor (GR) with the binding pose and interactions similar to its well-known ligand dexamethasone. Furthermore, knockdown of GR using siRNA abrogated JWH-015's ability to reduce IL-1ß-induced IL-6 and IL-8 production. In vivo, administration of JWH-015 (5 mg/kg, daily i.p. for 7 days at the onset of arthritis) significantly ameliorated AIA in rats. Pain assessment studies using von Frey method showed a marked antinociception in AIA rats treated with JWH-015. In addition, JWH-015 treatment inhibited bone destruction as evident from micro-CT scanning and bone analysis on the harvested joints and modulated serum RANKL and OPG levels. Overall, our findings suggest that CB2 agonist JWH-015 elicits anti-inflammatory effects partly through GR. This compound could further be tested as an adjunct therapy for the management of pain and tissue destruction as a non-opioid for RA.


Assuntos
Artrite Experimental/tratamento farmacológico , Fibroblastos/imunologia , Indóis/farmacologia , Interleucina-1beta/imunologia , Receptor CB2 de Canabinoide/agonistas , Receptores de Esteroides/imunologia , Membrana Sinovial/imunologia , Animais , Artrite Experimental/induzido quimicamente , Artrite Experimental/imunologia , Artrite Experimental/patologia , Feminino , Fibroblastos/patologia , Humanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/imunologia , Inflamação/patologia , Ratos , Ratos Endogâmicos Lew , Receptor CB2 de Canabinoide/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Membrana Sinovial/patologia
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