Acetic Acid Group Research Articles

Ibudilast ameliorates experimentally induced colitis in rats via down-regulation of proinflammatory cytokines and myeloperoxidase enzyme activity

Objectives: This study was carried out to explore the possible anti-inflammatory effect of ibudilast on acetic acid-induced colitis in rats. Methods: Fifty adult Wistar rats were separated into 5 groups, including the control group, acetic acid group, acetic acid + vehicle, acetic acid + sulfasalazine (100 mg/kg/day)group, and acetic acid + ibudilast (30 mg/kg/day) group. Colitis was induced in rats by the inter-rectal installation of 2 ml of 4% (v/v) acetic acid. Sulfasalazine and ibudilast were administered orally for ten days after 2 hours of induction. Results: The treatment with ibudilast significantly reduced disease activity index (DAI), macroscopic colonic scores (MAC), and histopathological changes induced by acetic acid. Also, ibudilast markedly decreased the expression of proinflammatory markers (TNF-α and IL-1β) in colonic tissue. Moreover, ibudilast inhibited myeloperoxidase (MPO) enzyme activity that was increased by acetic acid. Conclusion: Therefore, ibudilast may have a therapeutic effect in the management of ulcerative colitis.

Inula viscosa ameliorates acetic acid induced ulcerative colitis in rats

ABSTRACT Increased pro-inflammatory cytokines and oxidative stress contribute to the pathophysiology of ulcerative colitis (UC). Inula viscosa is a plant with antioxidant and anti-inflammatory properties. We investigated the effect of an ethanolic extract of I. viscosa on an experimental UC model created using acetic acid. Rats were divided into four groups of eight: group 1, control; group 2, 3% acetic acid group; group 3, 100 mg/kg sulfasalazine + 3% acetic acid group; group 4, 400 mg/kg I. viscosa + 3% acetic acid. I. viscosa and sulfasalazine were administered by oral gavage and 3% acetic acid was administered per rectum. We found that I. viscosa treatment decreased colon malondialdehyde, tumor necrosis factor-α, interleukin-1 beta and nuclear factor kappa B levels; it increased reduced glutathione, nuclear factor erythroid 2–related factor 2, heme oxygenase-1 and kelch-like ECH-associated protein 1 levels and glutathione peroxidase enzyme activity. Group 1 colon exhibited normal histological structure. Slight inflammatory cell infiltration and edema and insignificant slight erosion in crypts were detected in colon tissues of group 4. We found that I. viscosa reduced oxidative stress and inflammation, which was protective against UC by inducing the Nrf-2/Keap-1/HO-1 pathway in the colon.

Phytochemical Screening and Antioxidant Activity of Uncaria tomentosa Extract

Background: Uncaria tomentosa is a traditional medicinal herb with antiviral, antioxidant, immunostimulating, anti-inflammatory, and anticancer effects. Objective: The present study was conducted to evaluate the antioxidant capacity in vitro and in vivo and the phytochemical analysis of Uncaria tomentosa. Materials and Methods: The plant extract was screened for phytochemical compounds and antioxidant capacity in vitro using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method and in vivo using acetic acid-induced colitis. Colitis was induced in rats by transrectal administration (5 mL/kg) of 4% (v/v) acetic acid. Forty adult albino rats were divided into four groups: control group, acetic acid group, acetic acid + sulfasalazine (100 mg/kg/day) group, and acetic acid + Uncaria tomentosa extract (250 mg/kg/day) group. After inducing colitis, sulfasalazine and Uncaria tomentosa extract were given orally for 10 days. Data were statistically analyzed, and P < 0.05 was considered statistically significant throughout the study. Results: Preliminary phytochemical study showed that Uncaria tomentosa extract contains flavonoids, phenols alkaloids, saponin, and terpenoids. In the DPPH assay, the extract exhibited considerable antioxidant capacity in a dose-dependent manner. Also, Uncaria tomentosa extract dramatically decreased oxidative stress parameters, such as myeloperoxidase enzyme activity and malondialdehyde in colonic tissue. Moreover, Uncaria tomentosa treatment attenuated macroscopic colonic scores and histopathological changes induced by acetic acid. Conclusion: The findings of this study show that Uncaria tomentosa extract could be a source of natural antioxidants and may have a therapeutic effect on ulcerative colitis.

Efficacy of vaginal misoprostol soaked in acetic acid in the termination of missed miscarriages

Objective: To evaluate whether or not acetic acid-moistened intravaginal misoprostol is more effective than dry intravaginal misoprostol for inducing abortion at fewer than 24 weeks of gestation. Methodology: This cross-sectional study was performed at Department of Obstetrics and Gynecology, Al-Imamein Al-Kadhimain Medical City (IKMC), Baghdad from January to May 2022. Fifty outpatients with fetal death before 24 weeks were hospitalized for termination of pregnancy were included in the study. They were aged 15–42 years and had parity 0-6. The gestational age in weeks ranged from 13 to 24 weeks’ gestation. Participants were divided in 2 groups; first group on misoprostol and acetic acid and second group on misoprostol only. Results: There is significant difference mean of no. of doses and time of abortion between the 2 groups. Females who received misoprostol and acetic acid had less doses and less abortion time than those who received misoprostol only. Conclusion: Females who received misoprostol and acetic acid had less doses and less abortion time than females who received misoprostol only.

Protective effect of Melissa officinalis against acetic acid-induced ulcerative colitis in rat models: an experimental study.

Inflammation and oxidative activities within the gut play major roles in the pathogenesis of ulcerative colitis (UC). We aimed to determine the effect of Melissa officinalis, an antioxidant and anti-inflammatory agent, on the colon histological characteristics in acetic acid (AA)-induced UC in rat models. Thirty-six male rats with AA-induced colitis were divided into 5 groups: no treatment (AA); daily treatment with 300 mg/kg Melissa officinalis orally (MO) and rectally (MR); and 100 mg/kg mesalamine orally (AO) and rectally (AR). Macroscopic and histopathological evaluation of the colon, along with a biochemical laboratory evaluation, were performed 10 days after UC induction. All treatment groups demonstrated lower macroscopic grading scores compared to the AA group. After treatment with MO, 42.9% of cases demonstrated no macroscopic changes, while 14.3% demonstrated only mucosal erythema. In the MR group 28.6% of rats had no changes in their mucosal lining and 28.6% had only mucosal erythema. Following histopathological evaluation, the AO group had lower scores regarding the severity of ulcer, inflammation, destruction, crypt abscess, and disorganization compared to the MO group. (P=0.02) The MR group demonstrated lower microscopic scores compared to the MO group, and also lower macroscopic scores compared to the AR group, although not significantly (P>0.05). Both oral and topical administration of Melissa officinalis have satisfactory healing properties compared to mesalamine, with topical route having better results. Therefore, further studies are needed to establish the benefit of Melissa officinalis administration (both orally and topically) within a UC treatment protocol.

Bio-Oil Production from Multi-Waste Biomass Co-Pyrolysis Using Analytical Py–GC/MS

Background: Bioenergy attracts much attention due to the global demand for renewable and sustainable energy resources. Waste biomass feedstocks—date pits, coffee waste, and cow dung—require efficient and environmentally friendly waste-management technologies such as pyrolysis. Fast pyrolysis occurs at fast heating rates (10–100 °C/s), generates high bio-oil yields, and is the most widely used process for biofuel generation. The aim of the study is to compare the effect of pyrolysis between single, binary, and ternary feeds on thermal degradation behavior and bio-oil composition. Methods: Thermogravimetric analysis (TGA) was conducted at 30 °C/min from room temperature to 850 °C to understand the thermal degradation behavior of the biomasses. A Pyroprobe® reactor—a micro-scale pyrolyzer—was used to conduct the fast pyrolysis at 500 °C with a heating rate of 10 °C/s, and the volatile contents were quantified using a gas chromatograph–mass spectrometer (GC/MS). Results: The (TGA) showed three main stages of decomposition following dehydration, devolatilization, and char degradation for the different single and multiple feeds. According to the identified compounds, the bio-oil components are broadly identified as aldehydes, amines, aliphatic, aromatics, alcohols, furans, ketones, and acids. The three single-biomass pyrolysis products have four compounds in common, acetic acid and ketone groups (acetic acid, 2-propanone, 1-hydroxy-, benzyl methyl ketone, and 1,2-cyclopentanedione). Conclusion: The bio-oil generated from the feeds comprises great potential for volatiles, diesel, and gasoline production with carbon atoms ranging from C2–C33. Future studies should focus on understanding the effect of procedural parameters, including blending ratio, temperature, and heating rates, on bio-oil composition. Additional molecular techniques should be employed to understand biomass components’ reaction mechanisms to produce useful bio-oil products.

AN IN VITRO STUDY TO EVALUATE AND PREVENT THE PRECIPITATION FORMED BY THE INTERACTION OF SODIUM HYPOCHLORITE AND CHLORHEXIDINE

Background:As endodontic irrigants, a combination of sodium hypochlorite and chlorhexidine has been advocated to enhance their antimicrobial properties, also known to produce a carcinogenic precipitate, parachloroaniline, making its elimination necessary. Aim: To evaluate maximum thickness and composition of the precipitate on root canal wall and its elimination by using various intermediate irrigants. Materials and Methods: Working length was determined for the decoronated teeth. Biomechanical preparation was done till F2 Protaper le. The canals were irrigated between each instrumentation with 1 ml 2.5% NaOCl. Irrigation was done with 17% EDTA (5 ml) followed by 2.5% NaOCl (5ml) and nal ush with 2.5% CHX (5 ml). Intermediate ushes of 5 ml of saline, distilled water, absolute alcohol, sonic irrigation device and distilled water combination, oxum and acetic acid in between NaOCl and CHX. After drying the teeth were split into two halves for stereomicroscopic observation and grading was done for precipitate. Statistical analysis: The data obtained were subjected to Chi square and ANOVA test. Results: Maximum precipitation was observed in coronal portion of each group. Absolute alcohol group showed no precipitation, acetic acid group showed orange brown discoloration without forming of any precipitate. Conclusion: Formation of parachloroanilinecan be prevented by using absolute alcohol and minimized using different intermediate irrigants.

Promotion of Catalytic Oxygen Reduction Reactions: The Utility of Proton Management Substituents on Cobalt Porphyrins.

Three ABAB-type cobalt meso-tetraarylporphyrins with fluorine (F-CoPor), acetic acid (AC-CoPor), and cyanoacetic acid (CN-CoPor) groups at the para-positions of phenyl rings at the 10,20-positions are synthesized and evaluated as catalysts for oxygen reduction reactions (ORRs). In density functional theory calculations, the frontier molecular orbitals of these complexes were found to be stabilized relative to model complexes with electron-withdrawing atoms or moieties on the meso-aryl rings. Electrochemical measurements suggest that electrodes with CN-CoPor (CN-CoPor/C) exhibit the most positive ORR potential values and the highest limiting current density in both acidic and alkali electrolytes, while the F-CoPor/C electrocatalyst exhibits extremely low ORR performance. The electron transfer numbers for the electrocatalysts are more than 3.0, indicating that a mixture of 2- and 4-electron transfer pathways occurs. The results demonstrate that coupling the hydrogen bonding properties and electron-withdrawing abilities through rational design of the substituent at the meso-position is an efficient way to modify the ORR performance.

"Theranekron: A Novel Anti-inflammatory Candidate for Acetic Acid-Induced Colonic Inflammation in Rats".

Inflammatory bowel disease (IBD) is characterized with chronic inflammation of gastrointestinal track. In the pathogenesis of IBD, inflammation is the main mechanism. Induction of inflammation triggers the oxidative stress that subsequently leading to apoptosis. Considering the all pathological mechanisms, many therapeutic agents have been used for IBD but because of serious side effects there is still a need for new therapeutic drugs. In this study, we aim to evaluate the possible protective effects of Theranekron (TH) on acetic acid (AA)- induced colonic damage and to describe the probable effect mechanisms of TH. Fourty female adult Wistar albino rats were divided into 5 groups. Following 24h fasting, colitis was induced by rectal instillation of AA. In TH group, a single dose of subcutaneous 0.2 ml TH was used. In treatment groups, 0.2 ml TH single dose or 100mg/kg sulfasalazine (SS) for 7 days were used after colitis induction. Normal salin was used for all applications in control group. Histopathologically hemorrhage, edema and inflammatory reactions were seen in AA group. TH and SS decreased the severity of lesions. Nuclear factor kappa B, Serum amyloid A, C-reactive protein, Growth-related oncogene, and Osteopontin expressions were markedly increased in AA group and TH markedly reduced these expressions. In Western analysis, decreased NF-kB and caspase-3 levels were observed with TH. Oxidative markers did not changed significantly. TH has a prominent anti-inflammatory effect on AA-induced colonic inflammation via NF-kB signaling whereas antiapoptic effects seem to be independent from this pathway.

Preparation of a novel heterogeneous palladium nanocatalyst based on carboxyl modified magnetic nanoparticles and its applications in Suzuki-Miyaura coupling reactions

In this paper, an active, recyclable and stable magnetic palladium nanocatalyst (Fe3O4@SiO2-DTPA-Pd) was reported which could catalyze Suzuki coupling reaction. The Pd was stably hold by the three nitrogen atoms at the inside and four acetic acid groups at the outside of the chelating ligand ethylenediaminepentaacetic acid (DTPA) on the surface of core-shell magnetic Fe3O4@SiO2 microspheres. The prepared Fe3O4@SiO2-DTPA-Pd was systematically characterized. Results showed its size was 10–20 nm with 0.535 mmol/g Pd2+/Pd0. It could monodisperse in liquid, was thermally stable and good magnetic response from the high saturation magnetization value at 35.9 emu/g. Its activity was evaluated through Suzuki coupling reactions between 14 types of aryl halides and phenylboronic acid under optimized reaction conditions. It exhibited excellent activities and good applicability to substituted iodobenzene and bromobenzene. The yield of 4-bromobenzonitrile was up to 97.93%. Furthermore, the Fe3O4@SiO2-DTPA-Pd catalyst was stable, reusable and conveniently recovered by applying an external magnetic field. After 20 consecutive reaction cycles, the yield was still above 85%, which showed a superior heterogeneous advantage over other catalysts reported in the literature and had the huge potential in actual application of industry.

Preliminary Studies of Antimicrobial Activity of New Synthesized Hybrids of 2-Thiohydantoin and 2-Quinolone Derivatives Activated with Blue Light.

Thiohydantoin and quinolone derivatives have attracted researchers’ attention because of a broad spectrum of their medical applications. The aim of our research was to synthesize and analyze the antimicrobial properties of novel 2-thiohydantoin and 2-quinolone derivatives. For this purpose, two series of hybrid compounds were synthesized. Both series consisted of 2-thiohydantoin core and 2-quinolone derivative ring, however one of them was enriched with an acetic acid group at N3 atom in 2-thiohydantoin core. Antibacterial properties of these compounds were examined against bacteria: Staphylococcus aureus, Bacillus subtilis, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae. The antimicrobial assay was carried out using a serial dilution method to obtain the MIC. The influence of blue light irradiation on the tested compounds was investigated. The relative yield of singlet oxygen (1O2*, 1Δg) generation upon excitation with 420 nm was determined by a comparative method, employing perinaphthenone (PN) as a standard. Antimicrobial properties were also investigated after blue light irradiation of the suspensions of the hybrids and bacteria placed in microtitrate plates. Preliminary results confirmed that some of the hybrid compounds showed bacteriostatic activity to the reference Gram-positive bacterial strains and a few of them were bacteriostatic towards Gram-negative bacteria, as well. Blue light activation enhanced bacteriostatic effect of the tested compounds.

Rupatadine ameliorated ulcerative colitis in rats via modulation of platelet-activatiweng factor/interleukin-6/vascular endothelial growth factor signalling pathway.

This study aimed to analyse the potential effect of rupatadine (RUP) on ulcerative colitis (UC) induced by acetic acid (AA). Forty male adult Wistar rats were divided into five groups: Control group: received vehicles for 14 days; AA model group: received AA at the 13th day; Sulfasalazine (SLZ) + AA group: received SLZ (250mg/kg) for 14 days and AA at the 13th day; RUP-3 + AA group: received RUP (3mg/kg/day) for 14 days and AA at the 13th day; and RUP-6 + AA group: received RUP (6mg/kg/day) for 14 days and AA at the 13th day. Evidence of UC was assessed both macroscopically and microscopically. Oxidative stress markers (total antioxidant capacity and malondialdehyde), antioxidant enzyme (superoxide dismutase), histamine and platelet-activating factor (PAF) were determined. Immunohistochemical estimations of vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6) were done. The AA group showed evidence of UC that was associated with a significant increase in oxidative stress, histamine and PAF levels with significant elevation in colonic VEGF and IL-6 immuno-expressions. RUP, in a dose-dependent manner, significantly ameliorated UC. RUP protects against UC by reducing oxidative stress and by regulating the PAF/IL-6/VEGF pathway.

In situ forming heterointerface in g-C3N4/BiOBr photocatalyst for enhancing the photocatalytic activity

Removing wastewater with organic pollutants or medicine using semiconductor photocatalysts has attracted increasing attention in recent decades. However, low visible light utilization, high charge carrier recombination and insufficient surface active sites are still the limitation of photocatalysts. Herein, an in situ-forming BiOBr nanosheets on the surface of g-C3N4 were successfully synthesized via water bath in ambient temperature. The carboxyl group of acetic acid plays a vital role in growing for BiOBr nanosheets. The particular construction of g-C3N4/BiOBr composites increases the active sites and improve separation efficiency of photogenerated carriers, which strengthen photocatalytic degradation for pollutants. Meanwhile, electrons were transmitted quickly in the layered graphite carbon of g-C3N4 which owns excellent electrical conductivity. As a result, this work provides a novel approach to in-situ construction of semiconductor heterojunctions and demonstrates the prepared g-C3N4/BiOBr photocatalysts behave great potential in the removal of pollutants.

Endogenous Insulin: Study on Pain Threshold through Opioid Mechanism in Swiss Albino Mice

<p style="text-align: justify;"><strong>Background:</strong> There is no definitive conclusion on relationship between insulin and pain threshold through opioid mechanism in experimental animal model. The present study investigated the role of endogenous insulin in the modulation of pain using opioid drugs through opioid mechanism and their relationship in experimental animal model. <strong>Methods:</strong> Eight animal groups were used, each group consisting of six mice (Swiss albino). Group 1-treated saline ip; Group 2- administered pentazocine ip; Group 3- treated naloxone in low dose (0.005 mg/kg, ip) 15 min prior to pentazocine treatment; Group 4- administered naloxone in high dose (5 mg/kg, ip)15 min prior to pentazocine treatment. Another four groups of animals (Group 5, 6, 7 and 8) treated saline, pentazocine, low dose and high dose naloxone both administered 15 min prior to pentazocine treatment respectively. Group 1,2,3 and 4 subjected to acetic acid challenge and Group 5,6, 7 and 8 subjected to formalin test. Blood samples were collected and serum insulin was estimated by ELISA and blood glucose was measured by using Ames glucometer. <strong>Results:</strong> Pentazocine significantly increased both serum insulin and antinociceptive response to nociceptive stimuli to acetic acid as well as formalin challenge without significantly affecting plasma glucose in both pain models as compared to saline control. <strong>Conclusion: </strong>The study concluded that possible association between endogenous insulin and pain threshold which is independent of the glycemic status in both the chemically induced nociceptive tests. The relationship between endogenous insulin and pain threshold involves an interaction with opioid system possibly by binding with kappa receptor. <strong>Key words: </strong>Endogenous insulin, Plasma glucose, Pentazocine, Pain thresholds, Mice.

Synthesis, characterization and biological evaluation of some 2-arylbenzoxazole acetic acid derivatives as potential anticancer agents

A series of 2-arylbenzoxazole compounds possessing a cytotoxic activity as potential anticancer agents has been synthesised. Oxidative coupling of benzaldehyde with o -aminophenol utilizing lead tetraacetate approach has been used to realize the synthesis of compounds 1 - 11 . The cytotoxicity of 1 - 11 have been screened against breast cancer cell line MCF-7 and human colon cancer cell line HCT-116 utilizing doxorubicin as reference drug. Among these compounds, 2-(3-benzyloxyphenyl)benzoxazole-5-acetic acid 5 and 2-(4-methoxyphenyl)benzoxazol-5-acetic acid 10 , are found to be promising cytotoxic compounds against MCF-7 cell line. In addition, this study shows that the presence of acetic acid group at position 5 of benzoxazole nucleus enhances the activity. Moreover, it is noticed that the presence of oxygen atom directly linked to the phenyl substituent improves activity. The results offer a new benzoxazole based template to design and develop novel antineoplastic agents.

A novel role of pirfenidone in attenuation acetic acid induced ulcerative colitis by modulation of TGF-β1 / JNK1 pathway

Colon diseases are a major health burden, particularly ulcerative colitis, in both men and women worldwide. Environmental and genetic factors in various colonic pathologies influence the onset and outcome of diseases. As the evidence from recent research is considered, the importance of inflammation in the onset, progression, and outcome is gaining more traction. The goal of this study was to see if pirfenidone could treat ulcerative colitis (UC) and if so, what mechanisms were involved. By intracolonic instillation [2 ml, 3 percent v/v acetic acid (AA)], ulcerative colitis was induced. Pirfenidone was administered to rats in different experimental groups (125 or 250 and 500 mg/kg, orally) for two weeks. Compared to normal group, the AA group showed an increase in colon weight, length, body weight, clinical evaluation, and macroscopic scoring of UC, serum lactate dehydrogenase, C-reactive protein, malondialdehyde, while decreasing serum total antioxidant capacity. Significant increases in colon Jun N terminal kinase1 (JNK1), transforming growth factor-beta (TGF-β1), interleukin 1 beta (IL1β), and Caspase-3 content. Furthermore, immunohistochemical staining revealed increased nuclear factor kappa B (NF-κB) expression along with histopathological changes. Pirfenidone inhibited inflammatory biomarkers release and restored oxidants/antioxidants hemostasis. In a dose-dependent manner, pirfenidone treatment showed a significantly decrease in all of these parameters. In addition, pirfenidone has significantly preserved the histopathological architecture of tissues. Current data demonstrate that Pirfenidone protects against AA-induced UC by modulating the TGF-β1/JNK1 and Caspase-3 pathways. Pirfenidone's antioxidant, anti-inflammatory, and anti-apoptotic properties are thought to be responsible for its therapeutic benefit.

Flavocoxid halts both intestinal and extraintestinal alterations in acetic acid-induced colitis in rats.

Ulcerative colitis (UC) is an idiopathic chronic inflammatory disorder mainly affecting the colon and rectum. The present investigation was undertaken to evaluate the potential protective effect of flavocoxid, a dual COX and LOX inhibitor, in colitis model in rats. UC was induced by instillation of 2 ml of 4% acetic acid (AA) into the colon using a pediatric catheter in rats, and flavocoxid (10 and 20 mg·kg-1) was given once daily for 7 days before induction of colitis. Rats were sacrificed; sera were collected; colons and livers were isolated and then analyzed by biochemical, macroscopic, and histopathological examination. Pretreatment with flavocoxid (10 and 20 mg·kg-1) significantly reduced serum levels of alanine transaminase (ALT) (43.7 ± 7 and 76.2 ± 7.3 vs. 288.7 ± 31.4 in AA group) and aspartate transaminase (AST) (179.5 ± 22.2 and 200.5 ± 14 vs. 392.7 ± 35.6 in AA group) (p>0.05). Also, it decreased malondialdehyde (MDA) and nitric oxide (NOx) levels in both colonic and hepatic tissues. Moreover, flavocoxid effectively elevated colonic and hepatic reduced glutathione (GSH) level and superoxide dismutase (SOD) activity when compared to AA group (p>0.05). Additionally, flavocoxid significantly decreased levels of tumor necrosis factor-α (TNF-α) (878.2 ± 13.4 and 560.1 ± 2.9 vs. 1378.1 ± 31 in AA group) in colonic tissues and (701 ± 6.9 and 442.5 ± 8.2 vs. 1501 ± 9.4 in AA group) in hepatic tissues, nuclear factor kappa B (NF-κBp65) (493.8 ± 6.8 and 368.7 ± 3.1 vs. 659.2 ± 9.4 in AA group) in colonic tissues and (358 ± 5.1 and 163.5 ± 7.8 vs. 732.5 ± 4.5 in AA group) in hepatic tissues, myeloperoxidase (MPO) (15.7 ± 0.3 and 13 ± 0.2 vs. 20.9 ± 0.5 in AA group) in colonic tissues and (20.4 ± 0.3 and 16.3 ± 0.3 vs. 23.9 ± 1.2 in AA group) in hepatic tissues, and inducible nitric oxide synthase (iNOS) (12.5 ± 0.3 and 10 ± 0.2 vs. 16 ± 0.1 in AA group) in colonic tissues and (14.1 ± 0.04 and 11.5 ± 0.08 vs. 17.8 ± 0.1 in AA group) in hepatic tissues (p>0.05). Furthermore, it down-regulated Bax and caspase-3 expression in colonic and hepatic tissues upon comparison with AA group. Collectively, flavocoxid conferred a protective impact against acetic acid-induced colitis in rats via attenuating oxidative stress, inflammation, and apoptosis.

Isatin derivatives as a new class of aldose reductase inhibitors with antioxidant activity

In this work, isatin was employed as the scaffold to design aldose reductase inhibitors with antioxidant activity. Most of the isatin derivatives were proved to be excellent in the inhibition of aldose reductase (ALR2) with IC50 values at submicromolar level, and (E)-2-(5-(4-methoxystyryl)-2,3-dioxoindolin-1-yl) acetic acid (9g) was identified as the most effective with an IC50 value of 0.015 μM. Moreover, compounds 9a–h with styryl side chains at the C5 position of isatin showed potent antioxidant activity. Particularly, the phenolic compound 9h demonstrated similar antioxidant activity with the well-known antioxidant Trolox. Structure-activity relationship and molecular docking studies showed that the acetic acid group at N1 and C5 p-hydroxystyryl side chain were the key structures to increase the aldose reductase inhibitory activity and antioxidant activity.

Chain-like 2-amino-4-thiazoleacetic acid tethered AuNPs as colorimetric and spectrophotometric probe for organophosphate pesticide in water and fruit samples

This investigation describes the detection of quinalphos (QP), one of the organophosphate pesticides using 2-amino-4-thiazoleacetic acid anchored AuNPs (ATA-AuNPs) via naked eye and spectrophotometry. The ATA-AuNPs were synthesized by a bottom-up approach and confirmed by UV–vis, XRD, zeta potential and HR-TEM analyses. The ATA-AuNPs exhibited absorption maximum at 521 nm and the HR-TEM images revealed the formation of chain-like morphology of ATA-AuNPs with an average size of 6.4 nm. The zeta potential value of −38.5 mV suggested that the –NH2 groups of ATA adsorbed on AuNPs surface and the acetic acid group was free from binding, which prevented the aggregation of AuNPs by electrostatic repulsion. The ATA-AuNPs solution color was changed to violet from wine-red upon the addition of 3.5 µM QP whereas the absorption at 521 nm was diminished with the appearance of a new peak around 650 nm. The ATA-AuNPs started to aggregate after the addition of 7.5 µM of QP and the size of ATA-AuNPs was increased to 10.7 nm due to aggregation. Since the free acid group of ATA was involved in hydrogen bonding with the sulphur atom of QP the ATA-AuNPs were aggregated. It is obvious from the solution color change that naked eye detection of 2.5 µM QP can be possible. The ATA-AuNPs showed excellent anti-interference ability towards QP even with 2850-fold higher concentration of major interferents. A good linearity was observed in the detection of 0.5 to 3.5 µM QP (R2 = 0.9971) with the lowest LOD of 14.37 µg L−1 (S/N = 3). The practicability of the developed colorimetric and spectrophotometric methods was examined by determining the QP levels in QP treated field water samples and fruit samples.

Damp heat resilient thermoplastic polyolefin encapsulant for photovoltaic module encapsulation

Thermoplastic polyolefin (TPO) is a non-crosslinking material used in photovoltaic module encapsulation. TPO thermal degradation and its weather stabilities are still not known. In this work, TPO laminates were prepared and subjected to extended damp-heat weather test. TPO encapsulant properties were studied and compared with the most commonly used encapsulant, Ethylene-Vinyl Acetate (EVA). Four times lower rate of transmittance loss and increment rate in the yellowness index values have been found for TPO compared to EVA laminate. Damp-heat induced degradation mechanism, and its components were studied using Raman and Fourier-transform-infrared (FTIR) spectroscopy. Raman spectra revealed that the carbonyl group loss rate at the edge is one order of magnitude higher than the center. FTIR has shown a higher rate of acetic acid and hydroxyl group formation in EVA as compared to the TPO. FTIR also demonstrated that TPO has a lower water absorption because of its nonpolar nature, whereas EVA shows more water absorption due to its polar nature. The rate of change in thermal properties of TPO and EVA encapsulants were studied through the heat-cool-heat cycle. A higher rate of increment in the degree of crystallinity is found for EVA as compared to the TPO encapsulant during the extended damp-heat acceleration test. This study helps to understand the TPO and EVA encapsulants degradation behavior, degradation components, and mechanism to the encapsulant researchers and PV module manufacturers when a PV module experiences the hot-humid conditions. This TPO may result in the industry adopting the different PV modules for fabricating.