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1.
Chembiochem ; 25(6): e202300834, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38284327

RESUMO

Leveraging liposomes for drug and nucleic acid delivery, though promising due to reduced toxicity and ease of preparation, faces challenges in stability and efficiency. To address this, we synthesized cationic amphiphiles from amino acids (arginine, lysine, and histidine). Histidine emerged as the superior candidate, leading to the development of three histidine-rich cationic amphiphiles for liposomes. Using the hydration method, we have prepared the liposomes and determined the optimal N/P ratios for lipoplex formation via gel electrophoresis. In vitro transfection assays compared the efficacy of our lipids to Fugene, while MTT assays gauged biocompatibility across cancer cell lines (MDA-MB 231 and MCF-7). The histidine-based lipid demonstrated marked potential in enhancing drug and nucleic acid delivery. This improvement stemmed from increased zeta potential, enhancing electrostatic interactions with nucleic acids and cellular uptake. Our findings underscore histidine's crucial role over lysine and arginine for effective delivery, revealing a significant correlation between histidine abundance and optimal performance. This study paves the way for histidine-enriched lipids as promising candidates for efficient drug and nucleic acid delivery, addressing key challenges in the field.


Assuntos
Lipossomos , Ácidos Nucleicos , Lipossomos/química , Aminoácidos , Histidina/química , Lisina/química , Transfecção , Arginina/química , Lipídeos/química , Cátions/química
2.
Chemosphere ; 345: 140473, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37866496

RESUMO

Due to its complex and, often, highly contaminated nature, treating industrial wastewater poses a significant environmental problem. Many of the persistent pollutants found in industrial effluents cannot be effectively removed by conventional treatment procedures. Advanced Oxidation Processes (AOPs) have emerged as a promising solution, offering versatile and effective means of pollutant removal and mineralization. This comprehensive review explores the application of various AOP strategies in industrial wastewater treatment, focusing on their mechanisms and effectiveness. Ozonation (O3): Ozonation, leveraging ozone (O3), represents a well-established AOP for industrial waste water treatment. Ozone's formidable oxidative potential enables the breakdown of a broad spectrum of organic and inorganic contaminants. This paper provides an in-depth examination of ozone reactions, practical applications, and considerations involved in implementing ozonation. UV/Hydrogen Peroxide (UV/H2O2): The combination of ultraviolet (UV) light and hydrogen peroxide (H2O2) has gained prominence as an AOP due to its ability to generate hydroxyl radicals (ȮH), highly efficient in pollutant degradation. The review explores factors influencing the efficiency of UV/H2O2 processes, including H2O2 dosage and UV radiation intensity. Fenton and Photo-Fenton Processes: Fenton's reagent and Photo-Fenton processes employ iron ions and hydrogen peroxide to generate hydroxyl radicals for pollutant oxidation. The paper delves into the mechanisms, catalyst selection, and the role of photoactivation in enhancing degradation rates within the context of industrial wastewater treatment. Electrochemical Advanced Oxidation Processes (EAOPs): EAOPs encompass a range of techniques, such as electro-Fenton and anodic oxidation, which employ electrode reactions to produce ȮH radicals. This review explores the electrochemical principles, electrode materials, and operational parameters critical for optimizing EAOPs in industrial wastewater treatment. TiO2 Photocatalysis (UV/TiO2): Titanium dioxide (TiO2) photocatalysis, driven by UV light, is examined for its potential in industrial wastewater treatment. The review investigates TiO2 catalyst properties, reaction mechanisms, and the influence of parameters like catalyst loading and UV intensity on pollutant removal. Sonolysis (Ultrasonic Irradiation): High-frequency ultrasound-induced sonolysis represents a unique AOP, generating ȮH radicals during the formation and collapse of cavitation bubbles. This paper delves into the physics of cavitation, sonolytic reactions, and optimization strategies for industrial wastewater treatment. This review offers a critical assessment of the applicability, advantages, and limitations of these AOP strategies in addressing the diverse challenges posed by industrial wastewater. It emphasizes the importance of selecting AOPs tailored to the specific characteristics of industrial effluents and outlines potential directions for future research and practical implementation. The integrated use of these AOPs, when appropriately adapted, holds the potential to achieve sustainable and efficient treatment of industrial wastewater, contributing significantly to environmental preservation and regulatory compliance.


Assuntos
Poluentes Ambientais , Ozônio , Poluentes Químicos da Água , Purificação da Água , Águas Residuárias , Peróxido de Hidrogênio/química , Raios Ultravioleta , Oxirredução , Purificação da Água/métodos , Ozônio/química , Poluentes Químicos da Água/análise
3.
Sci Total Environ ; 875: 162573, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36871711

RESUMO

Driven by the UN-SDGs of achieving food security and agricultural sustainability, it remains more challenging in degraded ecosystems to simultaneously improve the crop performance without creating unintended favour for excessive fertilization and associated environmental consequences. We assessed the N-use pattern of 105 wheat-growers in sodicity affected Ghaghar Basin of Haryana, India, and then experimented upon to optimize and identify indicators of efficient N use in contrasting wheat cultivars for sustainable production. The survey results revealed that majority of farmers (88%) have increased their reliance on N nutrition (∼18 % extra N), and even extended their duration of N scheduling (12-15 days) for better plant adaptation and yield insurance in sodicity stressed wheat; albeit to a greater extent in moderately sodic soils applying 192 kg N ha-1 in 62 days. The participatory trials validated the farmers' perception of using more than the recommended N in sodic lands. This could realize the transformative improvements in plant physiological [higher photosynthetic rate (Pn; 5 %) and transpiration rate (E; 9 %)] and yield [more tillers (ET; 3 %), grains spike-1 (GS; 6 %) and healthier grains (TGW; 3 %)] traits culminating in ∼20 % higher yield at 200 kg N ha-1 (N200). However, further incremental N application had no apparent yield advantage or monetary benefits. At N200, every additional kilogram of N captured by the crop beyond the recommended N improved grain yields by 36.1 kg ha-1 in KRL 210 and 33.7 kg ha-1 in HD 2967. Further, the varietal differences for N requirements, with 173 kg ha-1 in KRL 210 and 188 kg ha-1 in HD 2967, warrants the need of applying balanced fertilizer dose and advocate revision of existing N recommendations to cope up the sodicity induced agricultural vulnerability. Principal Component Analysis (PCA) and correlation matrix showed N uptake efficiency (NUpE) and total N uptake (TNUP) as the highly weighted variables illustrating strong positive association with grain yield, and potentially deciding the fate of proper N utilization in sodicity stressed wheat. Key insights suggested that combining participatory research with farmers' knowledge and local perspective could be decisive in better integration of technologies, and serving to adapt the real-time soil sodicity stress and sustaining wheat yields with economized farm profits.


Assuntos
Ecossistema , Triticum , Fazendas , Agricultura/métodos , Solo , Cloreto de Sódio , Grão Comestível
4.
Chem Asian J ; 17(20): e202200837, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-35993447

RESUMO

Apart from being the unit of proteins, amino acids have diverse roles. Here we have shown that amino acids guide the differential transportation of a dye molecule to the cellular organelles depending upon the property of their intrinsic functionality. We have conjugated the nitrobenzofurazan (NBD) moiety with two amino acids (lysine and histidine derivatives) with a linker. Both derivates are water-soluble and biocompatible in nature. Surprisingly, we found that lysine-conjugated NBD (NBD-Lys) stains lipid droplets whereas histidine-conjugated NBD (NBD-His) stains lysosomes. We also measured the spectral properties of these two NBD conjugates. The results depict that both conjugates are extremely stable both in air and under inert atmosphere, and the fluorescence of the derivatives remains almost unaltered at different pH. Further by altering the functionality of the side chain, we established the contribution of each functional group towards this differential organelle targeting.


Assuntos
Corantes Fluorescentes , Lisina , Corantes Fluorescentes/química , Água , Histidina , Aminoácidos , Coloração e Rotulagem , Organelas
5.
J Phys Chem A ; 124(28): 5896-5906, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32559102

RESUMO

Conformational isomers of an O-H···N hydrogen-bonded binary complex between para-fluorophenol (pFP) and a nonrigid primary amine base, cyclopropylamine (CPA), have been probed by means of laser-induced fluorescence (LIF) spectroscopy in a supersonic jet expansion. Two closely spaced electronic origin bands have been identified in the measured LIF excitation spectrum, and their assignments have been corroborated by making comparisons with the spectra of the parent pFP-NH3 complex recorded under the same expansion condition. The observation is consistent with the presence of endo and exo isomeric variants of the complex predicted by electronic structure theory methods, and the endo isomer is stabilized by ∼2 kcal/mol additionally owing to the formation of a C-H···O and a C-H···π type of weak hydrogen bonds between the two moieties. In the fluorescence excitation (FE) spectrum, the low-frequency bands for different intermolecular modes gain substantial intensity, and this spectral feature is in contrast to that of the pFP-NH3 complex. The Franck-Condon intensity of the bands has been simulated invoking Duschinsky rotation scheme, taking into consideration the ground- and excited-state geometries.

6.
Org Lett ; 22(11): 4294-4299, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32452685

RESUMO

Herein, we illustrate that molecular oxygen (O2) is capable of promoting oxidative radical acylarylation of olefins with aliphatic aldehydes to afford acylated oxindoles in good yield (up to 97%). The key aspect of the process is the utilization of aldehyde auto-oxidation in developing aerobic radical olefin acylarylation. Kinetic studies confirm a lag phase for the reaction. Synthetic utility of the method is apparent via the preparation of biologically potent spirocyclic oxindoles and tetrahydrofuranoindolines.

7.
Field Crops Res ; 220: 67-77, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29725161

RESUMO

Rice is the staple food and provides livelihood for smallholder farmers in the coastal delta regions of South and Southeast Asia. However, its productivity is often low because of several abiotic stresses including high soil salinity and waterlogging during the wet (monsoon) season and high soil and water salinity during the dry season. Development and dissemination of suitable rice varieties tolerant of these multiple stresses encountered in coastal zones are of prime importance for increasing and stabilizing rice productivity, however adoption of new varieties has been slow in this region. Here we implemented participatory varietal selection (PVS) processes to identify and understand smallholder farmers' criteria for selection and adoption of new rice varieties in coastal zones. New breeding lines together with released rice varieties were evaluated in on-station and on-farm trials (researcher-managed) during the wet and dry seasons of 2008-2014 in the Indian Sundarbans region. Significant correlations between preferences of male and female farmers in most trials indicated that both groups have similar criteria for selection of rice varieties. However, farmers' preference criteria were different from researchers' criteria. Grain yield was important, but not the sole reason for variety selection by farmers. Several other factors also governed preferences and were strikingly different when compared across wet and dry seasons. For the wet season, farmers preferred tall (140-170 cm), long duration (160-170 d), lodging resistant and high yielding rice varieties because these traits are required in lowlands where water stagnates in the field for about four months (July to October). For the dry season, farmers' preferences were for high yielding, salt tolerant, early maturing (115-130 d) varieties with long slender grains and good quality for better market value. Pest and disease resistance was important in both seasons but did not rank high. When farmers ranked the two most preferred varieties, the ranking order was sometimes variable between locations and years, but when the top four varieties that consistently ranked high were considered, the variability was low. This indicates that at least 3-4 of the best-performing entries should be considered in succeeding multi-location and multi-year trials, thereby increasing the chances that the most stable varieties are selected. These findings will help improve breeding programs by providing information on critical traits. Selected varieties through PVS are also more likely to be adopted by farmers and will ensure higher and more stable productivity in the salt- and flood-affected coastal deltas of South and Southeast Asia.

8.
J Hazard Mater ; 180(1-3): 204-11, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20451322

RESUMO

Degradation of leather industry wastewater by sole aerobic treatment incorporating Thiobacillus ferrooxidans, Fenton's reagents, and combined treatment was investigated in this study. The sole treatment by Fenton's oxidation involving the introduction of 6g FeSO(4) and 266 g H(2)O(2) in a liter of wastewater at pH of 3.5 and 30 degrees C for 30 min at batch conditions reduced COD, BOD(5), sulfide, total chromium and color up to 69%, 72%, 88%, 5%, 100% and T. ferrooxidans alone showed maximum reduction to an extent of 77, 80, 85, 52, 89, respectively, in 21 d treatment at pH 2.5, FeSO(4) 16 g/L and temperature of 30 degrees C. The combined treatment at batch conditions involving 30 min chemical treatment by Fenton's oxidation followed by 72 h biochemical treatment by T. ferrooxidans at batch conditions gave rise up to 93%, 98%, 72%, 62% and 100% removal efficiencies of COD, BOD, sulfide, chromium and color at pH of 2.5 and 30 degrees C. Decrease in photo absorption of the Fenton's reagent treated samples, as compared to the banks, at 280, 350 and 470 nm wave lengths was observed. This may be the key factor for stimulating the biodegradation by T. ferrooxidans.


Assuntos
Peróxido de Hidrogênio/química , Resíduos Industriais , Ferro/química , Curtume , Poluentes da Água/metabolismo , Aerobiose , Concentração de Íons de Hidrogênio , Oxirredução , Thiobacillus/crescimento & desenvolvimento , Thiobacillus/metabolismo
9.
Eur Urol ; 42(6): 590-3, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12477655

RESUMO

INTRODUCTION: Many studies confirm the fact that radiographic anatomy of inferior calyx has a significant role in the clearance of a stone lodged in it [Br. J. Urol. 50 (1978) 449; Invest. Urol. 18 (2) (1980) 167; BJU Int. 83 (Suppl) (1999) 24; J. Urol. 132 (1984) 1085]. Acutely angled and narrow infundibular neck of a inferior calyx has a poorer stone clearance in comparison to that with a less acute angled and wider infundibular neck [Br. J. Urol. 50 (1978) 449; Invest. Urol. 18 (2) (1980) 167; Br. J. Urol. 82 (1998) 12; BJU Int. 83 (Suppl) (1999) 24]. Incidence of bilateral stones in clinical practice is significantly less than unilateral stones. This study was taken up to define the significance of radiographic anatomy of the inferior calyx as a risk factor predisposing to stone formation in a patient and compared the anatomy of inferior calyx of the stone forming and contralateral kidney. The fact that inspite of the similar known etiological factors (intrinsic and extrinsic) of stone formation, why stone forms unilaterally? MATERIAL AND METHODS: 100 consecutive cases of non-obstructed unilateral inferior calyceal calculus with non-metabolically active stones were studied. The infundibuloureteropelvic angle (IUPA) and infundibular width of the stone forming and non-stone forming contralateral side were compared. RESULTS: IUPA of stone forming side was more acute than the non-stone forming side, in 74% of the cases, more obtuse in 18% of the cases, and same in 8% of the cases. The difference in the IUPA of the stone forming and that of non-stone forming contralateral side was statistically significant (p<0.0002). The infundibular width of the stone forming side ranged from 1 to 16 mm and that of non-stone forming side from 2 to 11 mm. There was no statistically significant difference between the infundibular width of both the sides. Exactly, how and more importantly under what influences the macromolecules in the urine transforms into a calculus in the pelvicalyceal system is still not known till date but from our observations we conclude that IUPA is a significant risk factor which predisposes to calculus formation in inferior calyx. CONCLUSION: IUPA is a significant risk factor, which predisposes to urolithiasis in inferior calyx.


Assuntos
Cálculos Renais/etiologia , Cálices Renais , Pelve Renal/anatomia & histologia , Ureter/anatomia & histologia , Humanos , Fatores de Risco
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