Nickel nanoparticles induces cytotoxicity, cell morphology and oxidative stress in bluegill sunfish (BF-2) cells

The rationale of the current study was to assess the suitability of BF-2 cell line as a model to assess nanotoxicity in the caudal fin cells of bluegill sunfish in vitro. The current study investigates the potential toxicity, morphological changes and oxidative stress of nickel nanoparticles (Ni NPs) in bluegill sunfish cells (BF-2) using mitochondrial, neutral red uptake and lactate dehydrogenase assays. Results indicated a concentration dependent cytotoxic effect after 24 h in mitochondrial, lysosomal and lactate dehydrogenase activities. BF-2 cells morphology was altered when exposed to 30 μg ml−1 concentrations of Ni NPs for 24 h. Dose dependent increase of oxidative stress was evidenced in BF-2 cells when exposed to Ni NPs, showed significant escalation in peroxidation of lipids (LPO), protein carbonyl (PC), glutathione sulfo-transferase (GST) and glutathione peroxidase (GPX) as compared to their experimental controls. However, the catalase (CAT) and total glutathione content (TGSH) was found to decrease dose dependently in BF-2 cells exposed to Ni NPs. The current study demonstrated that BF-2 cells may serve as a sensitive indicator for aquatic contaminant evaluations in toxicological research.publishe

Investigation of the effect of Au2O3 dopant on elastic properties of PbO-B2O3-SeO2: Er2O3 glass ceramics by ultrasonic techniques

Various elastic coefficients of Au2O3 doped PbO-B2O3-SeO2:Er2O3 (PBSE) glass ceramics were evaluated as functions of Au2O3 content using ultrasonic velocity measurements. The elastic coefficients and micro-hardness showed a decreasing tendency with the concentration of Au2O3. Such decrease is attributed to the increasing concentration of gold metallic particles and [SeO3]2- groups that acted as modifiers and induced imperfections in these samples. Obtained results were observed to be consistent with the conclusions drawn from spectroscopic studies that include X-ray photoelectron spectroscopy (XPS), infrared (IR), photoluminescence (PL) and positron annihilation (PAL) spectroscopy studies. Overall, these studies have revealed that even though, the presence of gold metallic particles is preferable for achieving superior luminescence and electrical properties, presence of such particles caused to decrease the elastic coefficients and micro-hardness of these glass ceramics. However, when the concentration of Au2O3 is increased beyond 0.075 mol%, we have observed a slight increase of elastic coefficients and micro-hardness.Comment: 6 pages, 8 figure

Relative sensitivity of the corpus luteum of different days of pregnancy to LH-deprivation in the rat and hamster

Deprivation of endogenous LH by LH antiserum (LH A/S) in 6-day pregnant rats did not affect the luteal or serum progesterone within 24 h. LH A/S treatment on day 7 or 8 of pregnancy, however, caused a 70 and 92% reduction in luteal progesterone, respectively, within 24 h. Serum levels of progesterone showed a similar reduction. In the case of pregnant hamster, unlike the rat, there was a significant decrease in progesterone in the serum, luteal and non-luteal compartments whether the A/S was administered on day 4, 5 or 6. There was more than a 10-fold increase in the luteal cholesterol esters within 24 h whether the A/S was given on day 6, 7 or 8 of pregnancy in the rat. Rat corpora lutea of days 6 and 8 of pregnancy reacted in a like manner to LH-deprivation, showing an increased utilization of [U-14C]glucose to form 14CO2 in vitro. In the rat, LH (25 μg NIH-S19) administration in vivo either on day 6 or day 8 of pregnancy, caused within 2 h an increase in serum and non-luteal progesterone, but luteal progesterone was unchanged. On the other hand, LH administration to hamsters on day 8 of pregnancy caused an increase in progesterone levels in serum, luteal and non-luteal tissue. Incubation of corpora lutea isolated from untreated 6- and 8-day pregnant rats with LH brought about an increase in progesterone secretion into the medium in both cases. The results show that, even though LH-deprivation does not apparently affect progesterone concentration in the corpus luteum of 6-day pregnant rats, it does affect other metabolic parameters such as glucose utilization and cholesterol turnover, suggesting that the corpus luteum of early pregnancy exhibits a continuous dependency on LH for the maintainence of metabolic functions

Studies on luteolysis: effect of antiserum to luteinizing hormone on sterols and steroid levels in pregnant hamsters

The effect of luteinizing hormone antiserum (LH A/S) on sterol and steroid levels in luteal and non-luteal ovarian compartments, and on serum steroid levels of pregnant hamsters, was studied. Injection (ip) of 0.1 ml of LH A/S on day 7 caused termination of pregnancy and morphological regression of the corpus luteum (CL) within 18-20 h of treatment, whereas LH-free non-immune serum had no effect. Within 3 h of administration of LH A/S the luteal progesterone levels fell from a control value of 36.0 ± 2.4 to 15.6 ± 3.4 ng/mg, and estrogen from a control value of 20.8 ± 3.4 to 12.2 ± 1.5 pg/mg. By 12 h progesterone had dropped to 7.3 ± 0.3 ng/mg whereas estrogen was undetectable by radioimmunoassay. Serum progesterone fell in 3 h from 5.53 ± 0.39 to 3.15 ± 0.26 ng/ml whereas estrogen fell from 172 ± 26 to 123 ± 9 pg/ml. The progesterone content of non-luteal ovarian tissue dropped in 3 h from 1.06 ± 0.01 to 0.47 ± 0.06 ng/mg and estrogen from 115.0 ± 1.5 to 11.0 ± 0.65 pg/mg. Both progesterone and estrogen were undetectable at 24 h. In the CL, free cholesterol concentration did not change significantly after A/S treatment, while esterified cholesterol increased from 2.82 ± 0.14 to 4.14 ± 0.25 μg/mg within 6 hand 5.52 ± 0.17μg/mgby 12 h. The results suggest that LH plays a critical role in the maintenance of CL of early pregnancy in the hamster and that deprivation of LH, even for periods as short as 3 h, significantly influences steroid production. The accumulation of cholesterol esters following LH-deprivation suggests that loss of cholesteryl esterase activity could be one of the events leading to luteolysis

Femtogram Detection of Explosive Nitroaromatics: Fluoranthene-Based Fluorescent Chemosensors

Herein we report a novel fluoranthene-based fluorescent fluorophore 7,10-bis(4-bromophenyl)-8,9-bis4-(hexyloxy)phenyl]fluoranthene (S-3) and its remarkable properties in applications of explosive detection. The sensitivity towards the detection of nitroaromatics (NACs) was evaluated through fluorescence quenching in solution, vapor, and contact mode approaches. The contact mode approach using thin-layer silica chromatograp- hic plates exhibited a femtogram (1.15 fg cm(-2)) detection limit for trinitrotoluene (TNT) and picric acid (PA), whereas the solution-phase quenching showed PA detection at the 2-20 ppb level. Fluorescence lifetime measurements revealed that the quenching is static in nature and the quenching process is fully reversible. Binding energies between model binding sites of the S-3 and analyte compounds reveal that analyte molecules enter into the cavity created by substituted phenyl rings of fluoranthene and are stabilized by strong intermolecular interactions with alkyl chains. It is anticipated that the sensor S-3 could be a promising material for the construction of portable optical devices for the detection of onsite explosive nitroaromatics

Fluoranthene based fluorescent chemosensors for detection of explosive nitroaromatics

A novel fluoranthene based fluorescent chemosensor for the detection of picric acid (PA) at the parts per billion (ppb) level was evaluated. Static fluorescence quenching was the dominant process by intercalative pi-pi interaction between fluoranthene (S-1) and nitroaromatics