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1.
Front Chem ; 12: 1325354, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38516612

RESUMO

Corrosion is a major problem that can lead to the degradation of metal structures. In this study, we developed a novel corrosion-protective coating for metal substrates based on a modified epoxy acrylate formulation reinforced with halloysite nanotubes (HNTs). Epoxy acrylate oligomers were first synthesized through the acrylation of epoxy using acrylic acid, followed by copolymerization with butyl methacrylate/vinyl acetate monomers to produce grafted epoxy acrylates (GEA). HNTs were then incorporated into the polymeric dispersion at weight loadings of 1%, 1.5%, and 2%. The corrosion resistance and waterproofing properties of the coatings were evaluated. The results showed that steel samples coated with HNTs-modified GEA showed no signs of rusting even after 16 days of immersion in a corrosive solution, whereas those coated with GEA alone showed rusting after only 9 days. These results demonstrate the effectiveness of HNTs-modified GEA coatings in protecting steel surfaces against corrosion. The coatings are also water-resistant and can be easily applied. This work provides a new approach to developing corrosion-protective coatings for metal substrates.

2.
Environ Sci Pollut Res Int ; 30(52): 112825-112835, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37840083

RESUMO

This study investigates the absorption behavior of natural dyes on silk fabric: madder roots (red dye) and amaltas (brown dye). The dyes were extracted under optimized conditions in an acidic medium. Binary mixtures of these dyes in different proportions were employed to develop various shades. This research work has explored the impact of single as well as binary mixture of chemical mordants on the dyeing behavior of natural dyes on silk. Al (Alum), iron (Fe), and tannic acid (T.A.) were used as pre- and post-mordants. Different concentrations of the dye mixtures were used to achieve different shades. The absorption behavior of the binary mixture of natural dyes was assessed using a spectra photometer Colori-spectra SF600. The study found that the highest color strength was achieved when an acidic extract with a table salt concentration of 2 g/100 mL was applied to silk fabric at 65 °C for 55 min and subjected to microwave treatment for 6 min. The study revealed excellent results for the selected binary mixtures of chemical mordants, such as (Al + Fe), (Al + T.A.), and (Fe + T.A.), in comparison by employing single mordants such as (Al, Fe, and T.A.).


Assuntos
Corantes , Seda , Têxteis , Plantas , Taninos
3.
Biomedicines ; 11(10)2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37893112

RESUMO

Piperazine is a privileged moiety that is a structural part of many clinical drugs. Piperazine-based scaffolds have attracted the attention of pharmaceutical and medicinal scientists to develop novel, efficient therapeutic agents owing to their significant and promising biological profile. In the current study, an ecofriendly ultrasonic-assisted synthetic approach was applied to achieve a novel series of 1-tosyl piperazine dithiocarbamate acetamide hybrids 4a-4j, which was evaluated for in vitro tyrosinase inhibition and thrombolytic and hemolytic cytotoxic activities. Among all the piperazine-based dithiocarbamate acetamide target molecules 4a-4j, the structural analogs 4d displayed excellent tyrosinase inhibition efficacy (IC50 = 6.88 ± 0.11 µM) which was better than the reference standard drugs kojic acid (30.34 ± 0.75 µM) and ascorbic acid (11.5 ± 1.00 µM), respectively, which was further confirmed by in silico induced-fit docking (IFD) simulation Good tyrosinase activities were exhibited by 4g (IC50 = 7.24 ± 0.15 µM), 4b (IC50 = 8.01 ± 0.11 µM) and 4c (IC50 = 8.1 ± 0.30 µM) dithiocarbamate acetamides, which were also better tyrosinase inhibitors than the reference drugs but were less active than the 4d structural hybrid. All the derivatives are less toxic, having values in the 0.29 ± 0.01% to 15.6 ± 0.5% range. The scaffold 4b demonstrated better hemolytic potential (0.29 ± 0.01%), while a remarkably high thrombolytic chemotherapeutic potential was displayed by analog 4e (67.3 ± 0.2%).

4.
PLoS One ; 18(8): e0289570, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37540654

RESUMO

This study used a dataset of 30 years (1990-2020) of daily observations from 24 meteorological stations in the northern highlands of Pakistan to assess trends in extreme precipitation indices. The RClimDex model was used to analyze the indices, and the Modified Mann-Kendal test and the Theil-Sen slope estimator were applied to determine trends and slopes, respectively. The results showed a significant decrease in total annual precipitation amount (PRCPTOT) with varying rates of negative trend from -4.44 mm/year to -19.63 mm/year. The total winter and monsoon precipitation amounts were also decreased during the past three decades. The intensity-based precipitation indices (RX1Day, RX5Day, R95p, R99p, and SDII) showed a significant decrease in extreme intensity events over time, while the count of consecutive dry days (CDD) and consecutive wet days (CWD) indicated a significant decrease in duration at multiple stations. The annual counts of days with precipitation more than or equal to 10 mm (R10), 20 mm (R20), and 25 mm (R25) exhibited a significant decrease in frequency of extreme precipitation events, with the decrease more pronounced in the northern parts of the study domain. The findings of this study indicate a significant decline in the intensity, frequency, and extent of precipitation extremes across the northern highlands of Pakistan over the past 30 years.


Assuntos
Mudança Climática , Estações do Ano , Paquistão
5.
Environ Monit Assess ; 195(8): 990, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37491409

RESUMO

Human interventions and rapid changes in land use adversely affect the adequate distribution of water resources. A research study was conducted to quantify the gap between demand and supply for irrigation water in Multan, Pakistan, which may lead to sustainable water management. Two remotely sensed images (Landsat 8 OLI and Landsat 5 TM) were downloaded for the years 2010 and 2020, and supervised classification method was performed for the selected land use land cover (LULC) classes and basic framework. During the evaluation, the kappa coefficient was found in the ranges of 0.83-0.85, and overall accuracy was found to be more than 80% which indicated a substantial agreement between the classified maps and the ground truth data for both years and seasons. The LULC maps showed that urbanization has increased by 49% during the last decade (2010-2020). Reduction in planting areas for wheat (9%), cotton (24%), and orchards (46%) was observed. An increase in planting areas for rice (92%) and sugarcane (63%) was observed. The changing LULC pattern may be related to variation in water demand and supply for irrigation. The irrigation water demand has decreased by 370.2 Mm3 from 2010 to 2020, due to the reduction in agricultural land and an increase in urbanization. Available irrigation water supply (canals/rainfall) was estimated as 2432 Mm3 for the year 2020 which was 26% less than that of total irrigation water demand (3281 Mm3). The findings also provide the database for sustainable water management and equitable distribution of water in the region.


Assuntos
Sistemas de Informação Geográfica , Tecnologia de Sensoriamento Remoto , Humanos , Paquistão , Monitoramento Ambiental/métodos , Urbanização , Grão Comestível , Conservação dos Recursos Naturais
6.
J Trace Elem Med Biol ; 79: 127234, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37302218

RESUMO

BACKGROUND: Colorectal tumor is a major cause of cancer morbidity and mortality both in USA and around the globe. Exposure to environmental toxicants such as toxic trace elements has been implicated in colorectal malignancy. However, data linking them to this cancer are generally lacking. METHODS: Accordingly, the current study was to investigate the distribution, correlation and chemometric evaluation of 20 elements (Ca, Na, Mg, K, Zn, Fe, Ag, Co, Pb, Sn, Ni, Cr, Sr, Mn, Li, Se, Cd, Cu, Hg and As) in the tumor tissues (n = 147) and adjacent non tumor tissues (n = 147) of same colorectal patients which were analyzed by flame atomic absorption spectrophometry employing nitric acid-perchloric acid based wet digestion method. RESULTS: On the average, Zn (p < 0.05), Ag (p < 0.001), Pb (p < 0.001), Ni (p < 0.01), Cr (p < 0.005) and Cd (p < 0.001) showed significantly higher levels in the tumor tissues compared with the non tumor tissues of patients, whereas mean levels of Ca (p < 0.01), Na (p < 0.05), Mg (p < 0.001), Fe (p < 0.001), Sn (p < 0.05) and Se (p < 0.01), were significantly elevated in the non tumor tissues than the tissues of tumor patients. Most of the elements revealed markedly disparities in their elemental levels based on food (vegetarian/nonvegetarian) habits and smoking (smoker/nonsmoker) habits of donor groups. The correlation study and multivariate statistical analyses demonstrated some significantly divergent associations and apportionment of the elements in the tumor tissues and non tumor tissues of donors. Noticeably, variations in the elemental levels were also noted for colorectal tumor types (lymphoma, carcinoids tumor and adenocarcinoma) and stages (I, II, III, & IV) in patients. CONCLUSION: Overall, the study revealed that disproportions in essential and toxic elemental concentrations in the tissues are involved in pathogenesis of the malignancy. These findings provide the data base that helps to oncologist for diagnosis and prognosis of colorectal malignant patients.


Assuntos
Neoplasias Colorretais , Oligoelementos , Humanos , Paquistão , Cádmio/análise , Chumbo/análise , Análise Multivariada , Oligoelementos/análise
7.
Heliyon ; 9(3): e14144, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36915557

RESUMO

Sun drying in the open air is quite popular worldwide. However, the use of solar dryers to preserve various perishable agricultural products is a relatively new area of study, and the long-term effects of this method are not yet fully understood. The slow drying process in direct sunlight can contaminate the dried materials by soil and insects. To overcome these challenges, we devised a sun drying system that included a heating part, a drying area, a portable stand, fans, and a 50-W photovoltaic panel. An alternate energy source was used to power the drying process during cloudy days and at night. Fresh Freestone peach, Golden apple, and Anaheim chilies weighing 10 kg each with the initial moisture content of 89%, 87%, and 75% on a wet basis (w.b), respectively, were used in the experiments. The final moisture content of the samples was reduced by an average of 16%, 15%, and 11% for Freestone peaches, Golden apples, and Anaheim chilies, respectively. The quality analysis was carried out to determine sample composition, total bacteria, and color of dried products. The results indicated that the dried products met the recommended quality standards for food products in terms of composition, total bacteria, and color. This research supports the use of a hybrid mixed-mode solar dryer for drying a wide range of perishable agricultural products.

8.
Molecules ; 28(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36677762

RESUMO

Allenes with two carbon-carbon double bonds belong to a unique class of unsaturated hydrocarbons. The central carbon atom of allene is sp hybridized and forms two σ-bonds and two π-bonds with two terminal sp2 hybridized carbon atoms. The chemistry of allenes has been well documented over the last decades. They are more reactive than alkenes due to higher strain and exhibit significant axial chirality, thus playing a vital role in asymmetric synthesis. Over a variety of organic transformations, allenes specifically undergo classical metal catalyzed cycloaddition reactions to obtain chemo-, regio- and stereoselective cycloadducts. This review briefly describes different types of annulations including [2+2], [2+2+1], [3+2], [2+2+2], [4+2], [5+2], [6+2] cycloadditions using titanium, cobalt, rhodium, nickel, palladium, platinum, gold and phosphine catalyzed reactions along with a mechanistic study of some highlighted protocols. The synthetic applications of these reactions towards the synthesis of natural products such as aristeromycin, ent-[3]-ladderanol, waihoensene(-)-vindoline and (+)-4-epi-vindoline have also been described.

9.
Membranes (Basel) ; 12(12)2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36557137

RESUMO

Sweat is a natural body excretion produced by skin glands, and the body cools itself by releasing salty sweat. Wetness in the underarms and feet for long durations causes itchiness and an unpleasant smell. Skin-friendly reusable sweat pads could be used to absorb sweat. Transportation of moisture and functionality is the current challenge that many researchers are working on. This study aims to develop a functional and breathable sweat pad with antimicrobial and quick drying performance. Three layered functional sweat pads (FSP) are prepared in which the inner layer is made of an optimized needle-punched coolmax/polypropylene nonwoven blend. This layer is then dipped in antimicrobial ZnO solution (2, 4, and 6 wt.%), and super absorbent polymer (SAP) is embedded, and this is called a functional nonwoven (FNW1) sheet. Electrospun nanofiber-based nanomembranes of polyamide-6 are optimized for bead-free fibers. They are used as a middle layer to enhance the pad's functionality, and the third layer is again made of needle-punched optimized coolmax/polypropylene nonwoven sheets. A simple nonwoven-based sweat pad (SSP) is also prepared for comparison purposes. Nonwoven sheets are optimized based on better comfort properties, including air/water vapor permeability and moisture management (MMT). Nonwoven webs having a higher proportion of coolmax show better air permeability and moisture transfer from the inner to the outer layer. Antimicrobial activity of the functional nonwoven layer showed 8 mm of bacterial growth, but SSP and FSP showed only 6 mm of growth against Staphylococcus aureus. FSP showed superior comfort and antibacterial properties. This study could be a footstone toward highly functional sweat pads with remarkable comfort properties.

10.
PLoS One ; 17(12): e0278027, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36520942

RESUMO

Novel azomethines derived from acefylline tethered triazole hybrids (7a-k) have been synthesized and evaluated against human liver cancer cell line (Hep G2) using MTT assay. The synthesized series of azomethines exhibited promising efficacy against liver cancer cell line. Screening of the synthesized series identified compound 7d with the least cell viability value (11.71 ± 0.39%) as the most potent anticancer agent in contrast to the reference drug acefylline (cell viability = 80 ± 3.87%). In this study, the potentials of the novel agents (7a-k) to inhibit liver cancer proteins were assessed. Subsequently, the structure-activity relationship of the potential drug candidates was assessed via ADME/T molecular screening. The cytotoxic potential of these derivatives was also investigated by hemolysis and thrombolysis. Their hemolytic and thrombolytic studies showed that all of these drugs had very low cytotoxicity and moderate clot lysis activity. Compound 7g (0.26% hemolysis) and 7k (52.1% clot lysis) were the least toxic and moderate thrombolytic agents respectively.


Assuntos
Antineoplásicos , Neoplasias Hepáticas , Humanos , Ensaios de Seleção de Medicamentos Antitumorais , Linhagem Celular Tumoral , Hemólise , Reposicionamento de Medicamentos , Estrutura Molecular , Proliferação de Células , Triazóis/farmacologia , Antineoplásicos/farmacologia , Relação Estrutura-Atividade , Relação Dose-Resposta a Droga
11.
Molecules ; 27(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36500331

RESUMO

The emerging concepts of sustainable textiles and controlled production strategy demands ideally zero emissions of contaminants into the aquatic environment. However, the currently in-practiced conventional processes in textiles dispose of a number of contaminants especially super toxic synthetic dyes as effluents. In recent years, nanomaterials have become attractive choice for eco-friendly removal of organic dyestuff. Accordingly, this article reports synthesis and characterization of biocomposite wherein copolymer of polyaniline (PANI) and Polypyrrole (PPY) was grafted onto hydroxyethyl cellulose (HEC). Further, adsorption properties of as-prepared composite were evaluated using textile dyes Rhodamine B (RhB) and methyl Orange (MO)- as model adsorbate. The characterization of novel biocomposite (HEC/PANI-PPy) was carried out using Fourier Transform Infrared (FT-IR), Brunauer-Emmett-Teller analyzer (BET), Scanning Electron Microscope (SEM), and powder X-ray diffraction (XRD). The operational parameters such as dye initial concentration, adsorbent amount, pH and contact time were also studied to evaluate the efficiency level of the prepared biocomposite. Interestingly, the composite-mediated adsorption of RhB and MO followed pseudo-second order and the Langmuir isotherm. It is found that the adsorption capacity HEC/PANI-PPy is 30.06 and 29.3 for RhB and MO respectively. Thus, HEC/PANI-PPy is an inexpensive and highly efficient adsorbent that could be employed for could be employed for the separation and removal of toxic organic dyes from polluted textile effluents.


Assuntos
Corantes , Poluentes Químicos da Água , Corantes/química , Polímeros/química , Pirróis/química , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química , Adsorção , Celulose , Cinética
12.
Int J Biol Macromol ; 183: 2174-2183, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34102237

RESUMO

Guar gum (plant-based polysaccharide) is a promising candidate with immense potential. It is used as emulsifier, thickener, stabilizer, and as binding agent in many industries. In the present project, it was planned to synthesize guar gum based polyurethanes by varying the amount of guar gum. Guar gum (GG) was used along with hydroxyl-terminated polybutadiene (HTPB) as soft segment, which was then reacted with isophorone diisocyanate (IPDI) to form PU pre-polymers. In last step, these -NCO terminated pre-polymers were extended with 1,4 butane diol as chain extender. The prepared polyurethane samples were then characterized by using FTIR, solid-state 1HNMR and X-ray diffraction (XRD). Thermal behavior of the samples was studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Results indicated that the incorporation of guar gum in PU backbone improved its thermal behavior and crystallinity.


Assuntos
Galactanos/química , Mananas/química , Gomas Vegetais/química , Poliuretanos/química , Butadienos/química , Butileno Glicóis/química , Cristalização , Elastômeros/química , Isocianatos/química , Estrutura Molecular , Relação Estrutura-Atividade , Temperatura
13.
Sci Rep ; 11(1): 9960, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976253

RESUMO

The current investigation was designed to remove halosulfuron methyl from aqueous media by means of neem seed powder (NSP) in batch modes. Characterizations of NSP were carried out by using EDX, SEM, FTIR, point of zero charge and surface analysis. Optimum operation conditions were scrutinized by studying the influence of different factors like solution pH, dose of NSP, contact time, initial halosulfuron methyl concentration and temperature. Result indicates the dependency of the removal of halosulfuron methyl on solution pH and maximal removal (54%) was achieved in acidic medium (i.e. pH 3.0). To identify the chemical surface of NSP, point of zero charge of NSP was determined and was found to be 6.5 which imply that the surface of NSP is positively charged below pH 6.6 and favored the anionic sorption. Kinetics of halosulfuron methyl were demonstrated well by pseudo second order due to highest R2 (0.99) owing to the nearness between experimental and calculated sorption capacities. Isotherm results imply that Langmuir was found to the principal model to explain the removal of halosulfuron methyl and maximum monolayer sorption capacity was determined to be 200 mg g-1. Thermodynamic parameters like ΔH°, ΔG° and ΔS° were calculated from van't Hoff plot and were found negative which suggest that removal of halosulfuron methyl is exothermic and spontaneous at low temperature. These outcomes insinuate that neem seed power may be a valuable, inexpensive and ecofriendly biosorbent for the removal of pesticides.

14.
Pak J Pharm Sci ; 33(2(Supplementary)): 855-860, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32863262

RESUMO

The drug resistance phenomenon in microbes is resulting in the ineffectiveness of available drugs to treat the infections. Thus, there is a continued need to discover new molecules to combat the drug resistance phenomenon. Norfloxacin is a fluoroquinolone antibiotic that is used for the treatment of urinary tract infections. In this research work, norfloxacin is structurally modified by hybridizing with a range of substituted acetohydrazidic moieties through a multistep reaction. The first step involves the coupling of norfloxacin 1 with methyl chloroacetate followed by the treatment with hydrazine hydrate to result in corresponding acetohydrazide 3. A range of substituted benzaldehydes were reacted with the acetohydrazide to form the targeted series of norfloxacin derivatives 4a-i. The final compounds were screened for antimicrobial activity. Among the tested compounds, 4c, 4d, 4e and 4f displayed better antifungal activity against F.avenaceum, while compound 4c and 4e were active against F. bubigeum.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Hidrazinas/síntese química , Hidrazinas/farmacologia , Norfloxacino/síntese química , Norfloxacino/farmacologia , Antifúngicos/síntese química , Antifúngicos/farmacologia , Benzaldeídos/química , Fungos/efeitos dos fármacos , Hidrazinas/química , Relação Estrutura-Atividade
15.
Curr Org Synth ; 17(6): 457-463, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32392115

RESUMO

BACKGROUND: The pyrano[2,3-c]pyrazole derivatives are important building blocks of many biologically active compounds owing to their diverse biological potential for example, anti-inflammatory, anticancer, anti-microbial and anti-oxidant properties. OBJECTIVE: Keeping in mind the wide range of applications of pyrano[2,3-c]pyrazoles, herein we intended to develop a novel synthetic methodology for dihydropyranopyrazoles. We were also interested in determining the influence of amino acids and dipeptides as a catalyst on the synthesis of pyrano[2,3-c]pyrazole derivatives. METHODS: To achieve our objectives, we used a one-pot multi-component reaction of ethyl 3-oxobutanoate, propanedinitrile, hydrazine monohydrate and several substituted benzaldehydes by using different catalysts and solvents to synthesize our desired products in the presence of various catalysts. RESULTS AND DISCUSSION: We found that optimal conditions for the preparation of pyrano[2,3-c]pyrazoles were L-cysteine (0.5 mol) in the presence of water:ethanol (9:1) at 90 °C. Various 1,4-dihydropyrano[2,3- c]pyrazoles were afforded by using several substituted benzaldehydes in 66-97% yields. CONCLUSION: We described a green and environmentally benign method to synthesize pyrano[2,3-c]pyrazoles in a one-pot four component reaction of ethyl 3-oxobutanoate, propanedinitrile, hydrazine monohydrate and different substituted benzaldehyde in the presence of L-cysteine in aqueous ethanol (9:1) at 90 oC. Excellent yields of the products, simple work-up, easily available starting materials, use of green solvents, naturally occurring catalyst, non-toxicity, non-chromatographic purification and environmentally benign reaction conditions are some main advantages of this protocol.


Assuntos
Cisteína/química , Piranos/síntese química , Pirazóis/síntese química , Benzaldeídos/química , Catálise , Química Verde/métodos , Água/química
16.
Pak J Pharm Sci ; 32(6(Supplementary)): 2829-2834, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32024621

RESUMO

Diabetes Mellitus is a chronic disease in which the infected cells do not have the ability to produce sufficient amount of insulin that resulted in the abnormality of carbohydrates metabolism and an increase in blood glucose level. Long time exposure to Diabetes Mellitus resulted in failure or dysfunction of different organs like kidneys, nerves, heart, eyes, etc. A common practice to cure diabetes is the use of α-glucosidase inhibitors which help in lowering the blood glucose level. We presented 1,2-benzothiazine 1,1-dioxide derivatives as novel and more potent α-glucosidase inhibitors via their in vitro and in silico screenings. Excellent enzyme inhibitions were observed for compounds 2, 8, 10 and 12 having IC50 values of 6.91, 14.0, 4.2, 5.9 and 29.2µ respectively which were found better than the reference acarbose (IC50=38.31µM). Molecular docking studies suggested high binding energies and good binding interactions of these compounds with the active site residues of the receptor protein. A good agreement was found between the results of both modes of evaluation. Moreover, the envisioned candidates have a good potential to treat diabetes.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Inibidores de Glicosídeo Hidrolases/farmacologia , Hidrazinas/farmacologia , Hipoglicemiantes/farmacologia , Tiazinas/farmacologia , alfa-Glucosidases/metabolismo , Acarbose/farmacologia , Humanos , Cinética , Simulação de Acoplamento Molecular/métodos , Relação Estrutura-Atividade
17.
Pak J Pharm Sci ; 32(5(Supplementary)): 2215-2222, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31894047

RESUMO

Synthesis and characterization of novel structural hybrids of ciprofloxacin linked with a variety of anilides have been described in this paper. Antitumor activity of these derivatives was assessed against liver cell line (Huh-7) using MTT assay. Among the synthesized derivatives, compound 6a inhibited the growth of tumor cells by displaying 68.36% cell viability at 100 µg/mL concentration which was then in-silico modelled to delineate the potential mechanistic insights for its antiproliferative activity. The PASS prediction indicated the TopII as potential anticancer target of compound 6a. The induced fit docking revealed that compound 6a inhibits the TopII with superior binding affinity and forms stronger contacts with active site's key residues responsible for DNA-TopII intercalation and catalytic inhibition consistent with its cytotoxic potential. Therefore, compound 6a can be considered as a potential lead for further optimization in the development of ciprofloxacin-derived anticancer drugs.


Assuntos
Anilidas/química , Antineoplásicos/síntese química , Ciprofloxacina/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Desenho de Fármacos , Desenvolvimento de Medicamentos , Humanos , Espectroscopia de Ressonância Magnética
18.
Chem Cent J ; 12(1): 46, 2018 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-29700704

RESUMO

Electrically conductive polyorthochloroaniline/chromium nanocomposites (POC/Cr NCs) were prepared by in situ chemical oxidative polymerization of orthochloroaniline in the presence of Cr nanoparticles (Cr NPs). The load percentage of Cr nanofiller was varied in POC matrix to investigate the effect of Cr nanoparticles on the properties of the nanocomposites. The composition, structure, and morphology of POC and its composites were examined by Scanning electron microscopy, Fourier transform infrared spectroscopy, and UV-visible spectroscopic analysis. The antibacterial potential of POC and its composites was evaluated by the disc diffusion method against Escherichia coli and Bacillus subtilis. The results showed the improved antibacterial potential with the increase in the load percentage of nanofiller. The electrical conductivity of polymer and its composites was measured and correlated with the load percentage. The results showed that electrical conductivity of the composites was enhanced with the increase in load percentage of Cr nanoparticles.

19.
PLoS One ; 13(2): e0192294, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29444132

RESUMO

This paper presents a simple bi-level multi-objective linear program (BLMOLP) with a hierarchical structure consisting of reservoir managers and several water use sectors under a multi-objective framework for the optimal allocation of limited water resources. Being the upper level decision makers (i.e., leader) in the hierarchy, the reservoir managers control the water allocation system and tend to create a balance among the competing water users thereby maximizing the total benefits to the society. On the other hand, the competing water use sectors, being the lower level decision makers (i.e., followers) in the hierarchy, aim only to maximize individual sectoral benefits. This multi-objective bi-level optimization problem can be solved using the simultaneous compromise constraint (SICCON) technique which creates a compromise between upper and lower level decision makers (DMs), and transforms the multi-objective function into a single decision-making problem. The bi-level model developed in this study has been applied to the Swat River basin in Pakistan for the optimal allocation of water resources among competing water demand sectors and different scenarios have been developed. The application of the model in this study shows that the SICCON is a simple, applicable and feasible approach to solve the BLMOLP problem. Finally, the comparisons of the model results show that the optimization model is practical and efficient when it is applied to different conditions with priorities assigned to various water users.


Assuntos
Abastecimento de Água , Tomada de Decisões , Movimentos da Água
20.
Int J Biol Macromol ; 111: 485-492, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29325747

RESUMO

Our current research work comprised of synthesis of a series of novel chitosan based water dispersible polyurethanes. The synthesis was carried out in three steps, in first step, the NCO end capped PU-prepolymer was formed through the reaction between Polyethylene glycol (PEG) (Mn = 600), Dimethylolpropionic acid (DMPA) and Isophorone diisocyanate (IPDI). In second step, the neutralization step was carried out by using Triethylamine (TEA) which resulted the formation of neutralized NCO terminated PU-prepolymer, after that the last step chain extension was performed by the addition of chitosan and followed the formation of dispersion by adding calculated amount of water. The proposed structure of CS-WDPUs was confirmed by using FTIR technique. The antimicrobial activities of the plain weave poly-cotton printed and dyed textile swatches after application of CS-WDPUs were also evaluated. The results showed that the chitosan incorporation in to PU backbone has markedly enhanced the antibacterial activity of WDPUs. These synthesized CS-WDPUs are eco-friendly antimicrobial finishes (using natural bioactive agents such as chitosan) with potential applications on polyester/cotton textiles.


Assuntos
Antibacterianos/química , Quitosana/química , Poliuretanos/química , Têxteis , Antibacterianos/síntese química , Quitosana/síntese química , Quitosana/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/patogenicidade , Etilaminas/química , Excipientes/química , Humanos , Hidroxiácidos/química , Isocianatos/química , Poliuretanos/síntese química , Poliuretanos/farmacologia , Propionatos/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade , Água/química
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