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1.
Langmuir ; 39(48): 17446-17457, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37975865

RESUMEN

A zeolitic imidazole framework (ZIF-67) template-derived cobalt@nitrogen-doped carbon-sulfur composite (ZIF-Co@NCS) was synthesized using a freeze-drying method and explored for lithium-sulfur (Li-S) batteries. Material characterizations confirmed the formation of the ZIF-Co@NCS composite. To fabricate the Li-S battery in a coin-type CR-2032 cell, the as-synthesized ZIF-Co@NCS composite having a sulfur content of ∼65% was used as a cathode material and coupled with a lithium metal anode. This battery demonstrated exceptional cycling stability over 600 charge-discharge cycles with a steady capacity of 550 mAh g-1 at 0.05 C-rate. The good electrochemical performance of the cathode was ascribed to the nanofeatures associated with the freeze-dried porous carbon structure, which offered enough space for the sulfur cathode. The enhanced trapping of polysulfide facilitated by the presence of the Co-N sites in the ZIF-Co@NCS composite led to excellent cycling stability. The derived cathode composite showed a high specific capacity, outstanding rate capability, and excellent cyclic stability rendering it a promising candidate for high-performance Li-S batteries. Detailed Li+ ion charge storage examined by means of Dunn's method revealed a significant capacitive mode of charge storage both at peak currents and nonpeak currents. The post-mortem analysis of the cycled cathode using X-ray diffraction and scanning electron microscopy at different depth-of-discharge (DOD) values revealed the stepwise formation of discharge products.

2.
Nutr Cancer ; 74(5): 1894-1906, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34338101

RESUMEN

Lung cancer is a first leading cause of cancer related death worldwide. Quercetin (QUE) has chemo-preventive effect against a variety of cancers. However, the molecular mechanism of QUE mediated inhibition of cancer cell migration and epithelial to mesenchymal transition (EMT) is not clear in lung cancer. Therefore, this study investigates the effect of QUE on EMT and metastasis of lung cancer cell line (A549). The MTT assay, scratch wound healing assay, Transwell migration and invasion assay performed to assess the cell viability and migration potential of lung cancer cells after treatment with different concentration of QUE. Further, chemokines gene expression was analyzed by qPCR and EMT markers were analyzed by immunocytochemistry and Western blot. QUE inhibits cell viability in a dose-dependent (10-80 µM) manner both at 24 and 48 h treatment. The Akt/MAPK/ß-catenin and EMT marker protein expressions were decreased significantly, whereas TIMP-2 expression was increased upon QUE treatment. QUE inhibits cell migration and invasion of A-549 cells. In addition, Immunocytochemistry result showed that QUE can reduce nuclear translocalisation of ß-catenin in A549 cells. Our results suggest that QUE can inhibit the metastatic potential in lung cancer by altering the Akt/MAPK/ß-catenin signaling pathway and inhibiting the nuclear translocation of ß-catenin.


Asunto(s)
Transición Epitelial-Mesenquimal , Neoplasias Pulmonares , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Humanos , Neoplasias Pulmonares/metabolismo , Invasividad Neoplásica , Proteínas Proto-Oncogénicas c-akt , Quercetina/farmacología , beta Catenina/metabolismo
3.
Molecules ; 27(22)2022 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-36431951

RESUMEN

In this paper, the impact of dust deposition on solar photovoltaic (PV) panels was examined, using experimental and machine learning (ML) approaches for different sizes of dust pollutants. The experimental investigation was performed using five different sizes of dust pollutants with a deposition density of 33.48 g/m2 on the panel surface. It has been noted that the zero-resistance current of the PV panel is reduced by up to 49.01% due to the presence of small-size particles and 15.68% for large-size (ranging from 600 µ to 850 µ). In addition, a significant reduction of nearly 40% in sunlight penetration into the PV panel surface was observed due to the deposition of a smaller size of dust pollutants compared to the larger size. Subsequently, different ML regression models, namely support vector machine (SVMR), multiple linear (MLR) and Gaussian (GR), were considered and compared to predict the output power of solar PV panels under the varied size of dust deposition. The outcomes of the ML approach showed that the SVMR algorithms provide optimal performance with MAE, MSE and R2 values of 0.1589, 0.0328 and 0.9919, respectively; while GR had the worst performance. The predicted output power values are in good agreement with the experimental values, showing that the proposed ML approaches are suitable for predicting the output power in any harsh and dusty environment.

4.
Biochem Biophys Res Commun ; 547: 44-51, 2021 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-33592378

RESUMEN

Troponin C type 1 (TNNC1) is commonly overexpressed in ovarian cancer. However, the biological implications of TNNC1 overexpression on ovarian cancer malignization and its related mechanism remain unknown. To elucidate these implications, we knocked out the TNNC1 gene in TNNC1-overexpressing SKOV-3-13 ovarian cancer cells using CRISPR/Cas-9 technology and observed the changes in metastatic phenotypes and related molecular pathways. TNNC1-knockout (KO) cells showed significantly reduced proliferation and colony formation when compared with TNNC1 wild-type cells (P < 0.01). In TNNC1-KO cells, wound healing, migration, and invasive phenotypes decreased. Upon observation of upstream regulators of epithelial-mesenchymal transition (EMT), levels of phosphorylated AKT (Ser-473 and Thr-308) and GSK-3ß (inactive form) were found to be decreased in TNNC1-KO cells. Accordingly, SNAIL and SLUG expression decreased and were almost completely localized in the cytoplasm following TNNC1 silencing. Regarding downstream EMT markers, N-cadherin and vimentin expression decreased, but E-cadherin expression increased. Related matrix metalloproteinase and chemokine expression generally decreased. TNNC1 deficiency also suppressed F-actin polymerization. In conclusion, TNNC1 overexpression contributes to the metastatic behavior of ovarian cancer by perturbation of EMT and actin microfilaments. Our results provide a better understanding of the detailed molecular mechanism of ovarian cancer metastasis associated with TNNC1 overexpression.


Asunto(s)
Actinas/metabolismo , Neoplasias Ováricas/prevención & control , Troponina I/metabolismo , Antígenos CD/metabolismo , Sistemas CRISPR-Cas , Cadherinas/metabolismo , Línea Celular Tumoral , Proliferación Celular , Transición Epitelial-Mesenquimal , Femenino , Técnicas de Silenciamiento del Gen/métodos , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Humanos , Metástasis de la Neoplasia , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Troponina I/genética , Vimentina/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Phys Chem Chem Phys ; 21(16): 8246-8256, 2019 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-30924480

RESUMEN

This study presents the influence of the Au content on the catalytic activity of Pd100-xAux catalysts for ethanol electrooxidation in alkaline media. Potentiostatic electrochemical synthesis of the catalysts is adopted to reduce the resistance at the catalyst support interface and ensure minimal precursor wastage. Characterization of the Pd100-xAux bimetallic catalysts has been done using field-emission scanning electron microscopy (FESEM), energy dispersive X-ray analysis (EDAX), EDAX elemental mapping, high-resolution transmission electron microscopy (HR-TEM) and selected area electron diffraction (SAED) studies. Cyclic voltammetry and chronoamperometry studies imply superior electrocatalytic activity of the Pd100-xAux compositions with at least 50% Au to Pd. The Pd70Au30 bimetallic demonstrates the lowest onset potential of 0.475 V vs. RHE and highest mass activity with excellent stability. The combined effects of increased hydroxyl coverage on the Au and a d-band center shift, due to the induced compressive strain, are correlated with the excellent catalytic activity of the Pd70Au30 bimetallic catalyst. This claim is verified by evaluating the catalytic activity and the d-band centers of the Pd100-xAux catalysts obtained from their valence band spectra. On the basis of experimental UPS data, the authors report a downward shift of the d-band center for the Pd70Au30 bimetallic, which ensures 'optimal chemisorption', leading to enhanced oxidation.

6.
Nutr Cancer ; 66(1): 38-46, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24320139

RESUMEN

Prostate cancer becomes an ideal target for chemoprevention because of its high incidence and extended natural history. The consumption of quercetin (plant flavonoid) in diet is associated with decreased risk of disease and many cancers but then this was not elucidated in prostate malignancy. Hence, a study in which the male Sprague-Dawley rats were induced prostate cancer by hormone (testosterone) and carcinogen (MNU) and simultaneously supplemented with quercetin (200 mg/Kg body weight) thrice a week, was conducted. After the treatment period, rats were killed; ventral and dorsolateral lobes of the prostate were dissected. Histology and oxidative stress markers LPO, H2O2, and antioxidant GSH level were measured in both lobes. The lipid peroxidation, H2O2, in (MNU+T) treated rats were increased and GSH level was decreased, whereas simultaneous quercetin-treated rats reverted back to normal level in both ventral and dorsolateral regions. The different patterns of PIN were observed with associated hyperplasia and dysplasia; changes in these regions and the occurrence of this lesion were reduced in simultaneous quercetin-treated rats. The study concluded that dietary quercetin prevented MNU + T-induced prostate carcinogenesis on both ventral and dorsolateral lobes of Sprague-Dawley rats.


Asunto(s)
Anticarcinógenos/farmacología , Neoplasias de la Próstata/prevención & control , Quercetina/farmacología , Testosterona/efectos adversos , Animales , Carcinógenos/toxicidad , Glutatión/metabolismo , Peróxido de Hidrógeno/metabolismo , Peroxidación de Lípido , Masculino , Próstata/efectos de los fármacos , Próstata/patología , Neoplasias de la Próstata/inducido químicamente , Ratas , Ratas Sprague-Dawley
7.
Cell Biochem Funct ; 32(5): 476-84, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24888707

RESUMEN

The insulin-like growth factor I (IGF-I) signalling pathway contributes a major role on various cancer cell proliferation, survival and cell cycle. The present study was aimed to investigate the effect of nimbolide on IGF signalling and cell cycle arrest in MCF-7 and MDA-MB-231 breast cancer cell lines. The protein expression of IGF signalling molecules and cell cycle protein levels was assessed by western blot analysis. In order to study the interaction of nimbolide on IGF-1 signalling pathway, IGF-I and phosphoinositide 3-kinase (PI3K) inhibitor (LY294002) were used to treat MCF-7 and MDA-MB-231 cells. Further, the cell cycle arrest was analysed by flow cytometry. The protein expression of IGF signalling molecules was significantly decreased in nimbolide-treated breast cancer cells. PI3K inhibitor and IGF-I with nimbolide treatment notably inhibited phosphorylated Akt. The cell cycle arrest was observed at the G0/G1 phase, and accumulation of apoptotic cells was observed in nimbolide-treated breast cancer cell lines. Nimbolide also increased the protein expression of p21 and decreased the cyclins in both the cell lines. Nimbolide decreases the proliferation of breast cancer cells by modulating the IGF signalling molecules, which could be very useful for the breast cancer treatment.


Asunto(s)
Factor I del Crecimiento Similar a la Insulina/farmacología , Limoninas/farmacología , Transducción de Señal/efectos de los fármacos , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Cromonas/farmacología , Regulación hacia Abajo/efectos de los fármacos , Femenino , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Humanos , Proteínas Sustrato del Receptor de Insulina/metabolismo , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Células MCF-7 , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Morfolinas/farmacología , Fosfohidrolasa PTEN/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Receptor IGF Tipo 1/metabolismo , beta Catenina/metabolismo
8.
Cell Biochem Funct ; 32(3): 217-28, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23963693

RESUMEN

Prostate cancer is responsible for major deaths globally after lung cancer. Nimbolide is an important constituent of neem, and it acts as a potent inhibitor for many cancer cells. The present study was designed to evaluate the effects of nimbolide on apoptosis and insulin-like growth factor (IGF) signalling molecules in androgen-independent prostate cancer (PC-3) cells line. Nimbolide (0.5-2 µM) treatment resulted in 50% inhibition at a dose of 2 µM in the PC-3 cell line. The mRNA expression of Fas ligand, Fas-associated death domain receptor (FADDR), Bcl-2-associated X protein (Bax), Bcl-2-associated death promoter (Bad), phosphatidylinositide 3-kinases (PI3K), Akt, IGF1, IGF1 receptor (IGF1R) and IGF binding protein 3 were quantified by reverse transcription polymerase chain reaction and protein expression of Bax, cytochrome c, X-linked inhibitor of apoptosis protein (XIAP), B-Cell Lymphoma 2 (Bcl-2), caspases -8, -9, -10 and -3, poly(ADP-ribose) polymerase (PARP), cleaved PARP, IGF1R, PI3K, Akt, p-Akt was determined by western blot analysis, in nimbolide-treated PC-3 cell line. Nimbolide-induced apoptosis by activating DNA fragmentation in PC-3 cells. Nimbolide treatment increased the mRNA of Fas ligand, FADDR, Bax, Bad and IGF binding protein 3, decreased PI3K, Akt, IGF1 and IGF1R, increased protein expression of caspases 8, 3, 10, 9, Bax and cytochrome c and decreased the expression of XIAP, Bcl2, cleaved PARP, p-Akt and IGF1R. The results suggest that nimbolide acts as a potent anti-cancer agent by inducing apoptosis and inhibiting cell proliferation via PI3K/Akt pathway in PC-3 cells.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Limoninas/farmacología , Proteína Oncogénica v-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Neoplasias de la Próstata/metabolismo , Somatomedinas/metabolismo , Línea Celular Tumoral/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Fragmentación del ADN/efectos de los fármacos , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Neoplasias de la Próstata/patología , Receptor IGF Tipo 1/metabolismo , Transducción de Señal/efectos de los fármacos
9.
Pestic Biochem Physiol ; 109: 18-33, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24581381

RESUMEN

Quinalphos (QP) is speculated to cause endocrine disruption through the generation of reactive oxygen species (ROS) by oxidative stress (OS). Exposure of QP decreased testosterone level considerably which resulted in reduced viable sperms in mice. The QP induced toxicity is initiated by the formation of free radicals as it is evidenced from the increased Lipid peroxidation (LPO) and diminution of antioxidant enzymes in testicular tissue. Increased serum cholesterol and reduced testicular cholesterol indicated the inhibition of cholesterol transport and biosynthesis in testicular tissues. Lack of cholesterol in testicular tissue impaired the steroidogenesis by down-regulating the expression of StAR protein, Cytochrome P450, 3ß-HSD and 17ß-HSD leading to reduced testosterone level. Treatment of Commelina benganlensis (CBE) and Cissus quadrangularis (CQE) significantly recovered the alterations in antioxidant profiles as well as increased LPO, thereby recovering the decreased mRNA expression levels of intermediate enzymes. However, CQE effectively protected the OS and prevented the inhibition of steroidogenesis thereby preventing male infertility.


Asunto(s)
Cissus , Commelina , Insecticidas/toxicidad , Compuestos Organotiofosforados/toxicidad , Extractos Vegetales/farmacología , 17-Hidroxiesteroide Deshidrogenasas/genética , 17-Hidroxiesteroide Deshidrogenasas/metabolismo , 3-Hidroxiesteroide Deshidrogenasas/genética , 3-Hidroxiesteroide Deshidrogenasas/metabolismo , Animales , Catalasa/metabolismo , Supervivencia Celular/efectos de los fármacos , Colesterol/sangre , Colesterol/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Glutatión Peroxidasa/metabolismo , L-Lactato Deshidrogenasa/metabolismo , Hormona Luteinizante/sangre , Masculino , Ratones , Fosfoproteínas/genética , Recuento de Espermatozoides , Espermatozoides/efectos de los fármacos , Superóxido Dismutasa/metabolismo , Testículo/efectos de los fármacos , Testículo/metabolismo , Testosterona/metabolismo
10.
J Colloid Interface Sci ; 669: 992-1005, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38759598

RESUMEN

Composite polymer electrolytes (CPEs) are a promising alternative to flammable conventional liquid electrolytes for high-safety lithium-ion batteries. Establishing low-cost filler that enhances the amorphous nature of polymer in the CPEs and exhibits efficient Lewis acid-base interaction between fillers and anions of lithium salt, leading to improved dissociation of salts for enhanced conduction, is indispensable. In this work, for the first time, we construct a solid composite polymer electrolyte of poly(vinylidene fluoride hexafluoropropylene) embedded LaFeO3 (LFO) particles prepared by solution casting and electrospinning methods and study their performances. The 5 wt% LFO filler embedded CPE made by means of solution casting and electrospinning methods exhibited the highest ionic conductivity of 5.9 × 10-4 and 1.49 × 10-3 S cm-1 at room temperature and electrochemical stability window up to 4.6 and 4.45 V, respectively. Further, as-assembled solid-state lithium-ion batteries using electrospun CPE showed an initial discharge capacity of 166 mAh/g at 0.1C-rate and solution-casted CPE showed excellent cycling stability with 98.6 % capacity retention at 0.3C-rate even at 50th cycle. Such excellent performance originated from the introduction of the LFO particles as filler into the polymer matrix to enhance the ionic conductivity, mechanical strength and lithium metal compatibility of the resulting CPEs.

11.
RSC Adv ; 14(34): 24898-24909, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39119280

RESUMEN

Mono-/dimeric-substituted pyridinium and pyrazolium bromides were prepared under conventional and solvent-free silica-supported domestic microwave conditions. The atom economy, environmental product mass intensity and product mass intensity for solvent-free reactions showed significant importance for the synthesis of target molecules. 4-Nitrobenzyl-substituted pyridinium bromide showed potent anticancer properties compared with mono-/dimeric-substituted pyridinium and pyrazolium bromides against a lung cancer cell line (A-549). Molecular simulation studies were carried out for mono-/dimeric-substituted pyridinium and pyrazolium bromide against protein human CDK1/cyclinB1/CKS2 using the AutoDock program.

12.
ACS Omega ; 9(6): 6709-6718, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38371774

RESUMEN

Alternative energy sources, such as biodiesel, play a vital role in environmental protection. Waste cooking oil (WCO) biodiesel has promising applications in compression ignition engines. A major problem regarding biodiesel implementation is the deterioration and materials incompatibility of existing fuel system components with biodiesel. Variations in the composition of fuel prompted by the inclusion of biodiesel cause a variety of issues in diesel engine fuel systems where the elastomer is generally utilized as the fuel hose material and sealings. In this experimental work, the effects of the diesel and WCO biodiesel blends (B8, B16, B24, and B100) on Buna-N, ethylene propylene rubber (EPR), and polystyrene (PS) were examined by the immersion test, which was conducted for 160 h at various immersion temperatures of 30, 60, and 80 °C, respectively. The study also showed that the use of elastomer materials like Buna-N, EPR, and PS in diesel engines fueled up to 20% WCO biodiesel blends is advantageous; the overall compatibility improves by 100% compared to that obtained using neat diesel. The outcome revealed remarkable behavior changes, including a minor increase in volume and a slight loss in tensile strength and hardness compared to that observed using neat diesel fuel. The expansion of rubber materials increases over 60 °C, although the rate of this process decreases above 80 °C. It has been found that the expansion of rubber materials is unaffected by the acid concentration of the WCO biodiesel blends but significantly affected by the moisture content.

13.
ACS Omega ; 8(44): 41243-41257, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37969999

RESUMEN

The main aim of the study was to reduce carbon emissions in the atmosphere using a novel Andropogon narudus (AN) biofuel using higher air temperatures and reducing the consumption of conventional fossil fuel (diesel). The use of a heat exchange chamber within the air intake manifold is a popular method to reduce hydrocarbon (HC) and carbon monoxide (CO) emissions during cold starts. A premixed charged compression ignition engine in the dual-fuel mode was used in this study with raw diesel, raw AN oil, AN70+D30, AN80+D20, AN80+D20 (35 °C), AN80+D20 (40 °C), and AN80+D20 (45 °C). A chamber was designed and analyzed to measure the exit temperature and density change and to determine the reduction in volumetric efficiency of the engine, using Ansys Fluent software. A sustainability assessment study was performed to understand the feasibility of the fuel and the design using the Pugh Matrix. The fuel AN80+D20 with an air temperature of 45 °C was found to be superior to all other fuels in terms of brake thermal efficiency, reaching at 32.1%. D100 used the least amount of energy, whereas AN80+D20 used the most. Engine HC emission was at the lowest (45.01 ppm) for AN80+D20 fuel at 45 °C air input and reached the highest (50 ppm) for AN100 fuel. With an air temperature of 45 °C, CO emission was at its lowest for AN80+D20 gasoline (0.018%) and was at its highest for AN100 (0.072%). Nitrogen oxide emissions were the highest for AN80+D20 fuel with an air temperature of 45 °C, with an air concentration of 1254 ppm, whereas they were the lowest for AN100 (900 ppm). CO2 values were reduced, with D100 showing the lowest levels and AN100 showing the highest. The smoke emission was minimum for AN80+D20 fuel at 45 °C, with a smoke number of 15 compared to 33 for D100 fuel. As per the Pugh Matrix assessment, AN80+D20 with 35 °C air temperature had higher scores compared to all of the other fuel mixtures.

14.
ACS Omega ; 8(38): 34281-34298, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37779972

RESUMEN

Depending on the heat content and compression ignition (CI) engine combustion, biodiesel is a viable substitute fuel. Biodiesel is an oxygenated, safe, sulfur-free, biodegradable, and renewable fuel. It may be utilized in CI engines in any combination with diesel fuel without requiring the engine to be significantly modified. Many research studies have been made with several biodiesels as diesel substitutes, including Pongamia pinnata, Jatropha curcas, Mangifera indica, and Madhuca longifolia. The topic of the current review is the potential of renewable fuels to outperform diesel fuel in terms of performance, combustion, and emission characteristics. In the present study, CI engines are fueled with biodiesels made from Man. indica, Mad. longifolia, and pongamia seed oil. Adopting low heat rejection (LHR) mode CI engines and adding an antioxidant agent in addition to the biodiesel blends may resolve the issue of these biodiesels' poorer performance and increased NO emission. Both these additions may provide positive approaches in both performance and emission.

15.
ACS Omega ; 8(42): 39067-39079, 2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37901555

RESUMEN

The present work covers the preparation of biodiesel from jatropha oil through the transesterification process followed by its characterization, and furthermore, performance and emission analyses were done in terms of blending biodiesel with fossil diesel and CuO nanoparticles. Jatropha biodiesel blends (B10, B20, and B30) were chosen for this preliminary investigation based on the observation that B20 outperformed other blends. Next stage B20 with copper oxide (CuO) nanoparticle concentrations of 25, 50, 75, and 50 ppm are used to examine the performance and emission characteristics of a constant speed single cylinder, 4-stroke, 3.5 kW compression ignition (CI) engine. Finally, The response surface methodology (RSM) was utilized to determine the optimal nanoparticle concentration for B20. The results revealed that the blend of B20 with 80 ppm nanoparticles had the highest desirability (0.9732), and the developed RSM model was able to predict engine responses with a mean absolute percentage error (MAPE) of 3.113%. A confirmation test with an error in prediction of less than 5% verified the model's adequacy. When comparing optimized B20CuO80 to diesel, brake specific energy consumption (BSEC) increased by 8.49% and brake thermal efficiency (BTE) was lowered by 3.34%. Hydrocarbon (HC), carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxide (NOx), and smoke emissions were reduced by 3.66% and 2.88%, 4.78%, 22.9%, and 20.54%, respectively, at 80% load. As a result, the B20 blend with nanoparticle concentrations of 80 ppm may be used in current diesel engines without engine modification.

16.
ACS Omega ; 8(10): 9187-9197, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36936311

RESUMEN

The ongoing depletion of the world's fossil fuel sources and environmental damage has compelled the quest for alternative energy. Excellent characteristics of biodiesel include its renewable nature, safety, absence of sulfur, environmental advantages, and biodegradability, which can eradicate the above problems. In this study, algal oil was characterized to obtain the fatty acid profile, and the free fatty acid value of algal oil suggested a two-step process of esterification and transesterification for efficient biodiesel production. The performance and emission results of biodiesel and its blends (B10, B20, and B30) were investigated in a constant speed, single-cylinder, 4-stroke, 3.5 kW compression ignition engine at different loads for arriving at an appropriate fuel blend ratio. The response surface methodology technique is used to predict the ideal composition of microalgae-diesel using the experimental data with due weightage for the optimization criterion. The predicted blend ratio of B25 was tested on the engine and authenticated. The findings recorded an improvement in brake thermal efficiency to 31.42% and reduction in brake specific energy consumption to 9.82 MJ/kW h, unburned hydrocarbon to 85 ppm, carbon monoxide to 0.164% v/v, carbon dioxide to 4.115% v/v, nitrogen oxides to 691 ppm, and smoke opacity to 16.93%.

17.
ACS Omega ; 8(19): 16545-16560, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37214702

RESUMEN

Under the roof of solid industrialization and accelerated intensification of multiple ranges of mobilization, a huge rise in precious fuel consumption and pollution was observed. Based on the recent hardships of fossil fuels, experts are undoubtedly eager in carrying out their research in renewable environment-friendly fuels. There have been many reviews of works considering the parameters and standards of biodiesel, which is only from various vegetable and seed oils. But very little review work was carried out on only plant-based biofuel. Plant-based fuel has a lower viscosity and higher volatility properties. The target of this review was to make a bridge to overcome these research gaps. This review extensively studies the biological background, production outcome, properties, and reliability of plant-based biofuel and also deeply investigates the feasibility of usage in a diesel engine. From deep investigation it was identified that most of the low viscous fuel had higher brake thermal efficiency (BTE) (2% to 4%) and NOx emission (5% to 10%) than high viscous biodiesel. The formation of hydrocarbon (HC), CO, and smoke emission was similar to high viscous biodiesel. Overall, the low viscous fuel effectively improves the engine behaviors.

18.
ACS Omega ; 8(40): 36686-36699, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37841135

RESUMEN

The rapid depletion of crude oil and environmental degradation necessitate the search for alternative fuel sources for internal combustion engines. Biodiesel is a promising alternative fuel for compression ignition (CI) engines due to its heat content and combustion properties. Biodiesel blends are used in various vehicles and equipment, such as cars, trucks, buses, off-road vehicles, and oil furnaces. Biodiesel can reduce emissions from CI engines by up to 75% and improve engine durability due to its high lubricity. However, biodiesel has some drawbacks, including a performance reduction and increased nitrogen oxide emissions. Therefore, this study aims to investigate using environmentally available biodiesel in a low-heat rejection engine and an antioxidant additive to enhance the performance and reduce nitrogen oxide emissions. India currently has several biodiesel sources, including mango seed oil, mahua oil, and pongamia oil, which can be effectively utilized in CI engines by adding l-ascorbic acid. The experimental work involves a single-cylinder 4-stroke water-cooled direct injection CI engine with a power output of 5.2 kW. The engine's cylinder head, piston head, and valves are coated with lanthanum oxide using the plasma spray coating technique, with a thickness of 0.5 mm. The coated and uncoated engines are tested with different proportions of mahua oil, mango seed oil, and pongamia oil. The results show that the engine's performance is significantly improved compared to the baseline engine at all loads. Additionally, these biodiesels exhibit a notable reduction in nitrogen oxide emissions when combined with l-ascorbic acid.

19.
Neurochem Res ; 37(4): 708-21, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22127757

RESUMEN

Polychlorinated biphenyls (PCBs) exposure produces neurodegeneration and induces oxidative stress. Neuroprotective role of quercetin, on PCBs induced apoptosis in hippocampus has not yet been studied. The present study is focused to see whether quercetin supplementation precludes against PCBs induced oxidative stress and hippocampal apoptosis. The results have shown that quercetin at 50 mg/kg bwt/30 days has protected oxidative stress in hippocampus of adult male rats. Quercetin, a free radical scavenger decreased the levels of oxidative stress markers in the hippocampus of simultaneous PCB+quercetin treated rats. The pro-apoptotic and anti-apoptotic molecules such as Bad, Bid, Bax and Bcl2 were altered in the hippocampus of experimental animals. PCBs increased the DNA damage and induced neurodegeneration were assessed by histological studies. PCB induced ROS may be linked to increased hippocampal neuronal apoptosis. Quercetin supplementation decreased the neuronal damage and scavenged the free radicals induced by PCBs and protects PCBs induced apoptosis and oxidative stress.


Asunto(s)
Apoptosis/fisiología , Hipocampo/metabolismo , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/fisiología , Bifenilos Policlorados/toxicidad , Quercetina/farmacología , Factores de Edad , Animales , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Hipocampo/efectos de los fármacos , Masculino , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Wistar
20.
J Environ Pathol Toxicol Oncol ; 41(2): 69-88, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35695653

RESUMEN

Cancer is a major cause of death worldwide with an increasing incidence rate and is considered a major public health problem. Distance metastasis to other tissues, high toxicity, and drug resistance of cancer cells to chemotherapy demand novel therapeutic approaches to treat cancer. Natural compounds from medicinal plants have been studied for therapeutic use in various malignancies. Nimbolide is an active principal compound from Azadirachta indica, which is an Asian traditional medicinal plant utilized historically as a remedy for a variety of diseases due to its antioxidant, anti-inflammatory, anti-cancer, and antimicrobial properties. It is a limonoid triterpene possessing potent anti-cancer effects in various types of cancers. It has been reported to induce multiple cytotoxic effects in tumor cells by modulating the cell proliferation, cell cycle, apoptosis, and metastasis by altering the various molecular signaling pathways. In the present review, we summarized all the in vitro and in vivo studies reporting the molecular targets of nimbolide for the therapeutic approaches in different types of cancer cells. We analyzed research publications up to September 2021 on the effect of nimbolide in various malignancies and the molecular mechanism of action. Nimbolide targets different signaling pathways including epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), insulin like growth factor (IGF), Wingless and INT-1 (Wnt)/ß-catenin, mitogen-activated protein kinases (MAPK)/c-Jun N-terminal kinases (JNK), phosphoinositide 3-kinase (PI3K)/AKT, tumor necrosis factor-α (TNF-α)/nuclear factor kappa B (NF-κß), and death receptor 5 (DR5) in several cancer cells. Nimbolide's widespread availability and absence of side effects, as well as understanding the molecular mechanism of nimbolide's action, will be useful to develop a therapeutic agent against cancer.


Asunto(s)
Limoninas , Apoptosis , Línea Celular Tumoral , Limoninas/farmacología , Limoninas/uso terapéutico , Fosfatidilinositol 3-Quinasas/metabolismo , Factor A de Crecimiento Endotelial Vascular/farmacología
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