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1.
Chemosphere ; 339: 139717, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37541442

RESUMO

Access to clean water is the mandatory requirement for every living being to sustain life. So, membrane-based integrated approach of adsorption and separation technology has recently been preferred by scientists over other conventional techniques, for wastewater treatment. Current research focused on the synthesis of novel imidazolium (A1) based IL, which was further functionalized with hydroxyapatite (HAp; extracted from Labeo rohita scales), to create possible solutions towards environmental remediation. Cellulose acetate (CA) was used for the fabrication of three different ionic liquid membranes. All the synthesized products were characterized by FTIR, XRD and TGA. Two dyes of different nature, i.e., congo red (anionic) and crystal violet (cationic) were selected because of their highly toxic and carcinogenic effects, for batch adsorption experiments. Antibacterial activity of the synthesized membranes was also evaluated against S. aureus. Results of the study revealed that CA-HA1 1:2 acted as the best adsorbent towards the removal of crystal violet, exhibiting removal efficiency of 98% with the contact time of 24 h while in case of congo red adsorption, CA-HA1 (1:2) proved as prime adsorbent with the removal efficiency of 96% for the same preceding contact time. Considering the antibacterial character of the synthesized membranes, CA-A1 (1:1) emerged as very efficient antibacterial agent with the inhibition zone of 50 mm after 48 h. The overall behavior of monolayer and multilayer adsorption was witnessed for both dyes while kinetic studies favored the pseudo-second order reaction for all adsorbents.


Assuntos
Poluentes Ambientais , Líquidos Iônicos , Poluentes Químicos da Água , Vermelho Congo , Líquidos Iônicos/toxicidade , Cinética , Durapatita , Violeta Genciana/química , Staphylococcus aureus , Corantes/química , Antibacterianos/toxicidade , Adsorção , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio
2.
Biomed Res Int ; 2022: 3605054, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36420094

RESUMO

A simple process based on the dual roles of both magnesium oxide (MgO) and iron oxide (FeO) with boron (B) as precursors and catalysts has been developed for the synthesis of borate composites of magnesium and iron (Mg2B2O5-Fe3BO6) at 1200°C. The as-synthesized composites can be a single material with the improved and collective properties of both iron borates (Fe3BO6) and magnesium borates (Mg2B2O5). At higher temperatures, the synthesized Mg2B2O5-Fe3BO6 composite is found thermally more stable than the single borates of both magnesium and iron. Similarly, the synthesized composites are found to prevent the growth of both gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) pathogenic bacteria on all the tested concentrations. Moreover, the inhibitory effect of the synthesized composite increases with an increase in concentration and is more pronounced against S. aureus as compared to E. coli.


Assuntos
Ferro , Magnésio , Magnésio/farmacologia , Boratos/farmacologia , Staphylococcus aureus , Escherichia coli , Bactérias
3.
J Taibah Univ Med Sci ; 17(3): 415-423, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35722241

RESUMO

Objective: This study aims to assess and report the predictive value of tissue p53 protein expression and serum p53 antibodies as a screening tool for oral potentially malignant disorders (OPMDs) cases with risk of malignant transformation. Methods: A case-control study was jointly conducted at the Department of Pathology and Oral and Maxillofacial Surgery in several dental institutes in the country from April 2016 to March 2017. A total of 180 eligible subjects (60 cases of OPMDs, 60 cases of oral squamous cell carcinoma, and 60 controls) were included in the study. Tissue p53 immunoreactivity was determined by immunohistochemistry, and serum concentrations of p53 antibodies were determined by enzyme-linked immunosorbent assay. Specimens were collected for laboratory investigations after obtaining written consent from both patients and controls. Results: Among the study participants, the recorded male to female ratio was close to 2:1, and most participants fell in the age range of 41-60 years and above. Of the 60 cases of OPMDs, the observed tissue p53 immunopositivity was 73.3% (n = 44) while for the p53 antibody, the seropositivity was 96.7% (n = 58). The sensitivity for p53 immunoreactivity was 73%, and specificity was 98.3% between OPMDs and healthy individuals. Conclusion: The present study provides evidence (for OPMDs) that serum p53 antibodies and p53 immunoreactivity could be used as a sensitivity test and a specific test, respectively, and may contribute to determining the potential of OPMD for malignant transformation risk.

4.
Int J Biol Macromol ; 176: 233-243, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33549668

RESUMO

A cost-effective and sustainable Calligonum polygonoides biomass based activated carbon (AC) was synthesized. The prepared AC was utilized in the fabrication of carbon-alginate beads for the adsorption of methylene blue (MB) textile dye from aqueous solution. The surface morphology, surface functional groups, elemental analysis and thermal behavior of the prepared beads were investigated using different analytical techniques. Batch adsorption experiments were performed to investigate the adsorption capacity of the beads. Effect of different parameters such as initial pH of MB solution, dose of adsorbent, contact time, initial concentration of MB and temperature were evaluated. The kinetic studies identified pseudo-second order model. Langmuir and Freundlich isotherm models were applied and fitted to the experimental equilibrium data. The beads showed a maximum adsorption capacity of 769 mg/g in basic pH at 30 °C while using 400 mg·L-1 of MB solution. The adsorption process was found to be endothermic and spontaneous as confirmed by the thermodynamic data. The fabricated beads were subjected to recycling which exhibited same adsorption efficiency after six regeneration cycles. The results showed that the AC-alginate beads impregnated with SDS have high adsorption capability and would be used for the efficient removal of cationic dyes from wastewater.


Assuntos
Alginatos/química , Carvão Vegetal/química , Azul de Metileno/química , Tensoativos/química , Poluentes Químicos da Água/química , Purificação da Água , Concentração de Íons de Hidrogênio , Cinética
5.
J Pak Med Assoc ; 71(10): 2364-2368, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34974572

RESUMO

OBJECTIVE: To detect antibodies against p53 in serum of patients of oral squamous cell carcinoma and oral potentially malignant disorders compared to healthy individuals. METHODS: The descriptive cross-sectional study was conducted at the departments of Oral and Maxillofacial Surgery, Peshawar Dental College, Peshawar, Khyber College of Dentistry, Peshawar, and the Pakistan Institute of Medical Sciences, Islamabad, Pakistan, from April, 2016 to March, 2017, and comprised serum of oral squamous cell carcinoma patients in group A, oral potentially malignant disorder patients in group B and healthy individuals in group C. Serum concentrations of anti-p53 antibodies were determined by enzyme-linked immunosorbent assay. Data was analysed using SPSS 20. RESULTS: Of the180 subjects, there were 60(33.3%) in each of the three groups. Circulating serum p53 antibodies were detected in 59(98.3%) cases in group A, 58(96.6%) in group B and in 20(33.3%) individuals in group C (p=0.001). CONCLUSIONS: The expression of circulating p53 antibodies in serum samples of squamous cell carcinoma and oral potentially malignant disorders patients indicates the potential to be a probable candidate for being taken as a diagnostic or prognostic biomarker.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Biomarcadores Tumorais , Carcinoma de Células Escamosas/diagnóstico , Estudos Transversais , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Proteína Supressora de Tumor p53
6.
Appl Radiat Isot ; 166: 109404, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32956924

RESUMO

The shortcomings in Boron neutron capture therapy (BNCT) and Hyperthermia for killing the tumor cell desired for the synthesis of a new kind of material suitable to be first used in BNCT and later on enable the conditions for Hyperthermia to destroy the tumor cell. The desire led to the synthesis of large band gap semiconductor nano-size Boron-10 enriched crystals of hexagonal boron nitride (10BNNCs). The contents of 10BNNCs are analyzed with the help of x-ray photoelectron spectroscopy (XPS) and counter checked with Raman and XRD. The 10B-contents in 10BNNCs produce 7Li and 4He nuclei. A Part of the 7Li and 4He particles released in the cell is allowed to kill the tumor (via BNCT) whereas the rest produce electron-hole pairs in the semiconductor layer of 10BNNCs suggested to work in Hyperthermia with an externally applied field.


Assuntos
Compostos de Boro/síntese química , Terapia por Captura de Nêutron de Boro/métodos , Nanopartículas/química , Animais , Boro/química , Boro/uso terapêutico , Compostos de Boro/química , Compostos de Boro/uso terapêutico , Humanos , Hipertermia Induzida/métodos , Isótopos/química , Isótopos/uso terapêutico , Microscopia Eletrônica de Transmissão , Nanopartículas/uso terapêutico , Nanopartículas/ultraestrutura , Nanotecnologia , Neoplasias/radioterapia , Neoplasias/terapia , Espectroscopia Fotoeletrônica , Pontos Quânticos/química , Pontos Quânticos/uso terapêutico , Pontos Quânticos/ultraestrutura , Análise Espectral Raman , Difração de Raios X
7.
Phytother Res ; 33(10): 2661-2684, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31453659

RESUMO

Several reviews have been published on Artemisia's derived natural products, but it is the first attempt to review the chemistry and pharmacology of more than 80 alkaloids and allied nitrogen compounds obtained from various Artemisia species (covering the literature up to June 2018). The pharmacological potential and unique skeleton types of certain Artemisia's alkaloids provoke the importance of analyzing Artemisia species for bioactive alkaloids and allied nitrogen compounds. Among the various types of bioactive Artemisia's alkaloids, the main classes were the derivatives of rupestine (pyridine-sesquiterpene), lycoctonine (diterpene), pyrrolizidine, purines, polyamine, peptides, indole, piperidine, pyrrolidine, alkamides, and flavoalkaloids. The rupestine derivatives are Artemisia's characteristic alkaloids, whereas the rest are common alkaloids found in the family Asteraceae and chemotaxonomically links the genus Artemisia with the tribes Anthemideae. The most important biological activities of Artemisia's alkaloids are including hepatoprotective, local anesthetic, ß-galactosidase, and antiparasitic activities; treatment of angina pectoris, opening blocked arteries, as a sleep-inducing agents and inhibition of HIV viral protease, CYP450, melanin biosynthesis, human carbonic anhydrase, [3H]-AEA metabolism, kinases, and DNA polymerase ß1 . Some of the important nitrogen metabolites of Artemisia include pellitorine, zeatin, tryptophan, rupestine, and aconitine analogs, which need to be optimized and commercialized further.


Assuntos
Alcaloides/farmacologia , Artemisia/química , Alcaloides/análise , Humanos , Compostos de Nitrogênio/farmacologia , Extratos Vegetais/farmacologia
8.
J Biomater Sci Polym Ed ; 30(9): 785-796, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31018777

RESUMO

Cellulose-based nanocomposites have gained much attention due to their remarkable biological properties such as biodegradability, biocompatibility, and low toxicity. In this research work, 1-h-3-methylimidazolium hydrogen sulfate ionic liquid was employed as an efficient solvent for preparation of cellulosic Ag-nanocomposites (CRC/AgNPs composite) from Neem plant. Ionic liquid plays a dual role in obtaining cellulose-rich compound (CRC; removing lignin and hemicellulose components) and plant's extract (phenolic compounds such as flavonoids, tannins, etc.) that reduces the AgNO3 into AgNPs for preparation of CRC/AgNPs composite. The prepared CRC/AgNPs composite was characterized using XRD, FTIR and SEM techniques. The XRD and FTIR spectral analysis showed the characteristic peaks assigned to cellulosic constituent and AgNPs. SEM analysis revealed the particles in the range from 26 to 56 nm. The CRC/AgNPs composite was evaluated for its antibacterial and mechanical properties. The antibacterial activity against S. aureus and E. coli for CRC/AgNPs composite was observed in comparison to CRC. Cell viability and morphology were performed on MC3T3-E1 cells which showed no as such toxicity for the prepared CRC/AgNPs composite. Moreover, the addition of CRC/AgNPs composite as a filler increased the compression strength of polymeric materials.


Assuntos
Celulose/química , Celulose/farmacologia , Líquidos Iônicos/química , Nanopartículas Metálicas/química , Nanocompostos/química , Nanotecnologia , Prata/química , Células 3T3 , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Força Compressiva , Imidazóis/química , Camundongos , Testes de Sensibilidade Microbiana
9.
Chemosphere ; 195: 21-28, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29248749

RESUMO

Over the past decades, Ionic liquids (ILs) have gained considerable attention from the scientific community in reason of their versatility and performance in many fields. However, they nowadays remain mainly for laboratory scale use. The main barrier hampering their use in a larger scale is their questionable ecological toxicity. This study investigated the effect of hydrophobic and hydrophilic cyclic cation-based ILs against four pathogenic bacteria that infect humans. For that, cations, either of aromatic character (imidazolium or pyridinium) or of non-aromatic nature, (pyrrolidinium or piperidinium), were selected with different alkyl chain lengths and combined with both hydrophilic and hydrophobic anionic moieties. The results clearly demonstrated that introducing of hydrophobic anion namely bis((trifluoromethyl)sulfonyl)amide, [NTF2] and the elongation of the cations substitutions dramatically affect ILs toxicity behaviour. The established toxicity data [50% effective concentration (EC50)] along with similar endpoint collected from previous work against Aeromonas hydrophila were combined to developed quantitative structure-activity relationship (QSAR) model for toxicity prediction. The model was developed and validated in the light of Organization for Economic Co-operation and Development (OECD) guidelines strategy, producing good correlation coefficient R2 of 0.904 and small mean square error (MSE) of 0.095. The reliability of the QSAR model was further determined using k-fold cross validation.


Assuntos
Anti-Infecciosos/química , Bactérias/efeitos dos fármacos , Líquidos Iônicos/farmacologia , Relação Quantitativa Estrutura-Atividade , Ânions , Cátions/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Líquidos Iônicos/química , Reprodutibilidade dos Testes
10.
Carbohydr Polym ; 181: 208-214, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29253965

RESUMO

In the present research work, dicationic ionic liquids, containing 1,4-bis(3-methylimidazolium-1-yl) butane ([C4(Mim)2]) cation with counter anions [(2HSO4)(H2SO4)0], [(2HSO4)(H2SO4)2] and [(2HSO4)(H2SO4)4] were synthesised. ILs structures were confirmed using 1H NMR spectroscopy. Thermal stability, Hammett acidity, density and viscosity of ILs were determined. Various types of lignocellulosic biomass such as rubber wood, palm oil frond, bamboo and rice husk were converted into levulinic acid (LA). Among the synthesized ionic liquids, [C4(Mim)2][(2HSO4)(H2SO4)4] showed higher % yield of LA up to 47.52 from bamboo biomass at 110°C for 60min, which is the better yield at low temperature and short time compared to previous reports. Surface morphology, surface functional groups and thermal stability of bamboo before and after conversion into LA were studied using SEM, FTIR and TGA analysis, respectively. This one-pot production of LA from agro-waste will open new opportunity for the conversion of sustainable biomass resources into valuable chemicals.


Assuntos
Ácidos/farmacologia , Biomassa , Líquidos Iônicos/farmacologia , Ácidos Levulínicos/metabolismo , Lignina/metabolismo , Bambusa/química , Catálise , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo , Viscosidade
11.
Environ Technol ; 39(12): 1522-1532, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28524800

RESUMO

Coating fertilizer particles with thin films is a possibility to control fertilizer release rates. It is observed that novel urea cross-linked starch-lignin composite thin films, prepared by solution casting, swell on coming into contact with water due to the increase in volume by water uptake by diffusion. The effect of lignin content, varied from 0% to 20% in steps of 5% at three different temperatures (25°C, 35°C and 45°C), on swelling of the film was investigated. By gravimetric analysis, the equilibrium water uptake and diffusion coefficient decrease with lignin content, indicating that the addition of lignin increases the hydrophobicity of the films. When temperature increases, the diffusion coefficient and the amount of water absorbed tend to increase. Assuming that swelling of the thin film is by water uptake by diffusion, the diffusion coefficient is estimated. The estimated diffusion coefficient decreases from 4.3 to 2.1 × 10-7 cm2/s at 25°C, from 5.3 to 2.9 × 10-7 cm2/s at 35°C and from 6.2 to 3.8 × 10-7 cm2/s at 45°C depending on the lignin content. Activation energy for the increase in diffusion coefficient with temperature is observed to be 16.55 kJ/mol. An empirical model of water uptake as a function of percentage of lignin and temperature was also developed based on Fick's law.


Assuntos
Lignina/química , Ureia/química , Difusão , Permeabilidade , Amido , Água , Purificação da Água
12.
Ultrason Sonochem ; 37: 310-319, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28427638

RESUMO

5-Hydroxymethylfurfural (HMF) has been identified as a promising biomass-derived platform chemical. In this study, one pot production of HMF was studied in ionic liquid (IL) under probe sonication technique. Compared with the conventional heating technique, the use of probe ultrasonic irradiation reduced the reaction time from hours to minutes. Glucose, cellulose and local bamboo, treated with ultrasonic, produced HMF in the yields of 43%, 31% and 13% respectively, within less than 10min. The influence of various parameters such as acoustic power, reaction time, catalysts and glucose loading were studied. About 40% HMF yield at glucose conversion above 90% could be obtained with 2% of catalyst in 3min. Negligible amount of soluble by-product was detected, and humin formation could be controlled by adjusting the different process parameters. Upon extraction of HMF, the mixture of ionic liquid and catalyst could be reused and exhibited no significant reduction of HMF yield over five successive runs. The purity of regenerated [C4C1im]Cl and HMF was confirmed by NMR spectroscopy, indicating neither changes in the chemical structure nor presence of any major contaminants during the conversion under ultrasonic treatment. 13C NMR suggests that [C4C1im]Cl/CrCl3 catalyses mutarotation of α-glucopyranose to ß-glucopyranose leading to isomerization and finally conversion to HMF. The experimental results demonstrate that the use of probe sonication technique for conversion to HMF provides a positive process benefit.


Assuntos
Biomassa , Celulose/química , Furaldeído/análogos & derivados , Glucose/química , Líquidos Iônicos/química , Sonicação , Catálise , Furaldeído/química
13.
Nat Prod Res ; 26(5): 484-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21809956

RESUMO

Vitex negundo Linn. (Verbenaceae) is used in traditional medical system for respiratory disorders. This study was carried out to investigate its cough-relieving potential. The antitussive effect of the butanolic extract of V. negundo (Vn) on sulphur dioxide (SO(2))-induced cough was examined in mice. Safety profile of Vn was carried out by observing acute neurotoxicity, median lethal dose (LD(50)) and behavioural signs. Vn dose-dependently (250-1000 mg kg(-1)) inhibited the cough provoked by SO(2) gas in mice and exhibited maximum protection after 60 min of administration. At 1000 mg kg(-1), Vn caused maximum cough-suppressive effects i.e. cough inhibition at 60 min was 67.4%, as compared to codeine (10 mg kg(-1)), dextromethorphan (10 mg kg(-1)) and saline having cough-inhibitory potential 75.7%, 74.7% and 0%, respectively. LD(50) value of V. negundo was found to be greater than 5000 mg kg(-1). In toxicity tests, no signs of neural impairment and acute behavioural toxicity were observed at antitussive doses and extract has been well tolerated at higher doses. These results indicate that V. negundo exhibits antitussive effect and it was found devoid of toxicity.


Assuntos
Antitussígenos/uso terapêutico , Tosse/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Vitex/química , Animais , Antitussígenos/efeitos adversos , Antitussígenos/química , Camundongos , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química
14.
Chest ; 132(5): 1472-5, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17646238

RESUMO

BACKGROUND: Biomass smoke has been associated with many diseases. The aim of this study was to evaluate the relationship between biomass smoke and chronic bronchitis in women in the rural setting of Peshawar, Pakistan. METHODS: Three villages in rural Peshawar were randomly selected as "test villages" where biomass fuel was used. The women responsible for cooking in these villages were interviewed for the prevalence of bronchitis, and data were compared to those obtained from three matching "control villages" where liquid petroleum gas was used as fuel. Crude odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using a statistical software package (EPI Info, version 6.0 [public domain software]; Centers for Disease Control and Prevention; Atlanta, GA). RESULTS: This study was carried out in 1,426 female test patients and 1,131 female control subjects. Chronic bronchitis was found in 100 women (7.01%) in the test group and 33 women (2.92%) in the control group. The OR was 2.51 (95% CI, 1.65 to 3.83). A strong association was found between bronchitis and the use of wood (OR, 2.38; 95% CI, 2.12 to 3.01), dung cake (OR, 2.01; 95% CI, 1.72 to 2.42), rice straws (OR, 3.32; 95% CI, 1.11 to 9.88), and kai grass (OR, 1.96; 95% CI, 1.75 to 2.45). Cooking in the living room and bronchitis were highly associated (OR, 2.5; 95% CI, 1.94 to 3.66). An association between the presence of a kitchen and bronchitis was established with an OR of 2.65 (95% CI, 2.10 to 3.42). In the test group, 75% of kitchens were ventilated; in the control group, 82% were ventilated. The difference between the two groups was nonsignificant (p>0.6; chi2=0.39; OR, 0.83; 95% CI, 0.5 to 1.4). CONCLUSIONS: Biomass fuel exposure is strongly associated with chronic bronchitis in women who are involved in cooking in rural Peshawar.


Assuntos
Poluição do Ar em Ambientes Fechados/efeitos adversos , Bronquite Crônica/etiologia , Culinária , Fumaça/efeitos adversos , Adulto , Biomassa , Bronquite Crônica/epidemiologia , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Feminino , Combustíveis Fósseis , Humanos , Paquistão/epidemiologia , Prevalência , Fatores de Risco , População Rural
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