Hr Of Exposure Research Articles

Gemini High-resolution Optical Spectrograph (GHOST) at Gemini South: Instrument Performance and Integration, First Science, and Next Steps

The Gemini South telescope is now equipped with a new high-resolution spectrograph called the Gemini High-resolution Optical SpecTrograph (GHOST). This instrument provides high-efficiency, high-resolution spectra covering 347–1060 nm in a single exposure of either one or two targets simultaneously, along with precision radial velocity spectroscopy utilizing an internal calibration source. It can operate at a spectral element resolving power of either 76,000 or 56,000, and can reach a signal-to-noise ratio of ∼5 in a 1 hr exposure on a V ∼ 20.8 mag target in median site seeing and dark skies (per resolution element). GHOST was installed on-site in 2022 June, and we report performance after full integration to queue operations in 2023 November, in addition to scientific results enabled by the integration observing runs. These results demonstrate the ability to observe a wide variety of bright and faint targets with high efficiency and precision. With GHOST, new avenues to explore high-resolution spectroscopy have opened up to the astronomical community. These are described, along with the planned and potential upgrades to the instrument.

Allergic Potential & Molecular Mechanism of Skin Sensitization of Cinnamaldehyde Under Environmental UVB Exposure

Fragrance, a key ingredient in cosmetics, often triggers skin allergy causes rashes, itching, dryness, and cracked or scaly skin. Cinnamaldehyde (CA), derived from the bark of the cinnamon tree, used as a fragrance and is a moderate skin sensitizer. CA exhibits strong UVB absorption, its allergic potential and the molecular mechanisms underlying skin sensitization under UVB exposure remain largely unexplored. To investigate the allergic potential and molecular mechanisms of CA-induced skin sensitization under ambient UVB radiation, we employed various alternative in-silico, in-chemico and in-vitro tools. CA under ambient UVB isomerizes from trans to cis CA after 1hr of exposure. Furthermore, DPRA assay and docking with simulation studies demonstrated the enhanced allergic potential of cis-CA. Additionally, our study evaluated intracellular ROS levels and the expression of Nrf2, Catalase, and MMP-2, and 9 in KeratinoSens cells, showing significant upregulation under UVB exposure in the presence of CA. Moreover, our findings indicate that CA activates THP-1 cells co-stimulatory surface marker (CD86) via the activation of intracellular ROS, phagocytosis, and genes of the TLR4 pathway. These insights into the mechanisms uncovered by our study are crucial for managing triggers of allergic skin diseases caused by fragrance use and concurrent exposure to environmental UVB/sunlight.

Abstract 09: Leucine Rich Repeat Containing 8A Anion Channels Modulate Vascular Reactivity in ApoE Knockout Mice

Volume-regulated anion channels (VRACs) are comprised of Leucine Rich Repeat Containing 8 (LRRC8) family proteins which include LRRC8A, B, C, D and E. We have proposed that these channels may allow influx of extracellular superoxide to drive inflammation and modulate cultured vascular smooth muscle cell (VSMC) inflammation. We previously demonstrated that LRRC8A knockdown or inhibition inhibits tumor necrosis factor alpha (TNFα)-induced inflammation. Mesenteric arteries from male smooth muscle-specific LRRC8A knockout (KO) mice displayed enhanced responsiveness to both endothelium-dependent (acetylcholine, ACh), and independent (sodium nitroprusside, SNP) vasodilators compared to vessels from WT mice. KO vessels were also protected from vascular dysfunction induced by TNFα in tissue culture (48hr exposure). We hypothesized that reduced VSMC inflammation in LRRC8A KO mice would protect vascular function in ApoE knockout (ApoE -/- ). We created ApoE -/- mice lacking LRRC8A only in VSMCs and assessed vascular reactivity of isolated mesenteric arteries by wire myography in female and male WT, Heterozygous (HET) and KO tissues after 14 weeks of high fat diet. WT vessels displayed enhanced in contraction compared to LRRC8A KO or HET (male PE max contraction of KCL (%), WT 177 ± 4.6 vs. KO 152 ± 3.3 or HET 153 ± 3.0, p < 0.05, n=6-7). Relaxation responses to ACh were increased in female KO or HET compared to WT (ACh LogEC 50 , WT -7.2 ± 0.09 vs. KO -7.5 ± 0.09 or HET -7.4 ± 0.07, p < 0.05, n=5-6). SNP-mediated relaxation were increased in male KO vessels compared to WT (SNP LogEC 50 , WT -8.1 ± 0.06 vs. KO -8.3 ± 0.06, p < 0.05, n=7). These results demonstrate that loss (KO) or reduction (HET) of LRRC8A expression preserves vascular function in the face of the inflammatory response induced by hypercholesterolemia in ApoE -/- mice. These channels may represent a novel therapeutic target for preservation of vascular function and this may only require partial inhibition of current.

Cytotoxic Effect of Biosynthesized Manganese Oxide Nanoparticles on Human Skin Squamous Carcinoma Cell Line (HSSCC) in vitro

The current study intended to biosynthesis of manganese oxide nanoparticles (MnO -NPs) depending on prodigiosin pigment as stabilizing and reducing agent. which produced from environmental isolate of Serratia marcescens . The study of the biosynthesis of MnO NPs was characterized by different techniques, such as ( UV-VIS, XRD, AFM, FE-SEM and FTIR). The results refer, the wavelength of biosynthesis of MnO NPs by using UV-VIS was (284 nm), the average volume was (45) nm). and image FE-SEM shows that the MnO- NPs mainly consists of nanosheets assembled in flower-like shape with different diameters. The cytotoxic effects of (MnO -NPs) on Human Skin Squamous Carcinoma Cell Line (HSSCC) was significant (p≤0.05) comparative with control viability 100%. Maximum effective concentration were 4000 μg/ml for 72hr exposure time which gave the highest inhibition rate 95% comparative with viability control 100%, but the minimum concentration was 3.9 μg/ml which induced proliferation of (HSSCC)cells. So when the exposure time and the concentration was increased, the inhibition rate was increased. Keywords:Serratia marcescens, Human skin squamous carcinoma cell line, cytotoxic effect, prodigiosin, MnO –NP.

Ecotoxicological assessment of UV filters benzophenone-3 and TiO2 nanoparticles, isolated and in a mixture, in developing zebrafish (Danio rerio)

ABSTRACT The increasing use of UV filters, such as benzophenone-3 (BP-3) and titanium dioxide nanoparticles (TiO2 NPs), has raised concerns regarding their ecotoxicological effects on the aquatic environment. The aim of the present study was to examine the embryo-larval toxicity attributed to BP-3 or TiO2 NPs, either alone or in a mixture, utilizing zebrafish (Danio rerio) as a model after exposure to environmentally relevant concentrations of these compounds. Zebrafish embryos were exposed to BP-3 (10, 100, or 1000 ng/L) or TiO2 NPs (1000 ng/L) alone or in a mixture (BP-3 10, 100, or 1000 ng/L plus 1000 ng/L of TiO2 NPs) under static conditions for 144 hr. After exposure, BP-3 levels were determined by high-performance liquid chromatography (HPLC). BP-3 levels increased in the presence of TiO2 NPs, indicating that the BP-3 degradation decreased in the presence of the NPs. In addition, in the presence of zebrafish, BP-3 levels in water decreased, indicating that zebrafish embryos and larvae might absorb BP-3. Data demonstrated that, in general, environmentally relevant concentrations of BP-3 and TiO2 NPs, either alone or in a mixture, did not significantly induce changes in heart and spontaneous contractions frequencies, levels of reactive oxygen species (ROS), morphological and morphometric parameters as well as mortality rates during 144 hr exposure. However, the groups exposed to TiO2 NPs alone and in a mixture with BP-3 at 10 ng/L exhibited an earlier significant hatching rate than the controls. Altogether, the data indicates that a potential ecotoxicological impact on the aquatic environment exists.

Abstract 4605: AZD4573 in combination with CHOP increases combination benefit in preclinical peripheral T-cell lymphoma models

Abstract Peripheral T-cell Lymphoma (pTCL) makes up about 10% of non-Hodgkin's lymphoma in the United States. Patients with relapsed/refractory pTCL have limited treatment options and poor prognosis. Current standard of care for pTCL revolves around the chemotherapy regimens CHOP/E. Here we examine the efficacy of CDK9 inhibition for the treatment of pTCL. CDK9 regulates transcription through phosphorylation of RNA polymerase II. AZD4573 is a highly potent and selective CDK9 inhibitor; acute inhibition with AZD4573 downregulates short-lived proteins such as MCL-1, BFL-1, and c-MYC, which are often overexpressed in hematologic tumors. It has been shown that the expression pattern of the anti-apoptotic BCL-2 family members in pTCL cell line models closely resembled the expression patterns in pTCL patient samples (Koch et al. 2019). Expression of BCL-2 family members is highly heterogeneous in pTCL, with MCL-1 being the most universally expressed. Using MCL-1 inhibitor AZD5991, we showed statistically significant benefit in survival when combined with CHOP in MCL-1 dependent preclinical pTCL PDX models (Koch et al. 2019). In addition, we have previously reported the importance of the anti-apoptotic protein BFL-1 in cell survival in NHL, including a subset of pTCL (Boiko et al 2021). AZD4573 treatment showed a range of activity across the panel of 18 human pTCL cell lines, in a 6-hour caspase-3/7 activation assay. 14 of the cell lines were sensitive, with EC50 values less than 100 nM, and 13 reached a max caspase activation of over 40%. pTCL subtypes that responded to AZD4573 treatment included ALCL, NK-TCL, and PTCL-NOS and CTCL. Acute AZD4573 treatment resulted in decreased pSer2-RNAP2 and reduced protein levels of c-MYC and MCL-1. To determine what was driving the apoptotic phenotype, we used ribonucleoprotein (RNP) mediated CRISPR knock out (KO) of MYC and MCL1 genes. While pTCL cell lines were dependent on c-MYC and MCL-1 for viability after KO, only MCL-1 KO impaired AZD4573 treatment, suggesting that efficacy is mediated through MCL-1 in ALCL pTCL cell lines assessed. To determine if combining AZD4573 with CHOP improved efficacy, we tested 5 pTCL cell lines in a 6x6 combination dosing matrix and measured viability after 24-72 hours using RealTime-Glo after 24hr exposure to CHOP with AZD4573 added for the last 6hrs. Adding AZD4573 to CHOP in vitro increased the efficacy in pTCL ALCL cell lines with MCL-1 dependency, but not in CTCL cell line with BCL-xL dependency and resistance to AZD4573. CHOP treatment in vitro resulted in a decrease in c-MYC levels but not MCL-1, suggesting that combination benefit may be driven through c-MYC. This data suggests that treatment with AZD4573 as a monotherapy or in combination with CHOP regimen would be an effective therapeutic strategy in pTCL. Citation Format: Danielle Sinead Potter, India Ott, Jamal Saeh, Richard Olsson, Stephen Fawell, Lisa Drew, Justine Roderick. AZD4573 in combination with CHOP increases combination benefit in preclinical peripheral T-cell lymphoma models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4605.

Novel high throughput screen reports that benzo(a)pyrene overrides mouse trophoblast stem cell multipotency, inducing SAPK activity, HAND1 and differentiated trophoblast giant cells

IntroductionCultured mouse trophoblast stem cells (mTSC) maintain proliferation/normal stemness (NS) under FGF4, which when removed, causes normal differentiation (ND). Hypoxic, or hyperosmotic stress forces trophoblast giant cells (TGC) differentiate. Hypoxic, hyperosmotic, and genotoxic benzo(a)pyrene (BaP), which is found in tobacco smoke, force down-regulation of inhibitor of differentiation (Id)2, enabling TGC differentiation. Hypoxic and hyperosmotic stress induce TGC by SAPK-dependent HAND1 increase. Here we test whether BaP forces mTSC-to-TGC while inducing SAPK and HAND1. MethodsHand1 and SAPK activity were assayed by immunoblot, mTSC-to-TGC growth and differentiation were assayed at Tfinal after 72hr exposure of BaP, NS, ND, Retinoic acid (RA), or sorbitol. Nuclear-stained cells were micrographed automatically by a live imager, and assayed by ImageJ/FIJI, Biotek Gen 5, AIVIA proprietary artificial intelligence (AI) software or open source, CellPose artificial intelligence/AI software. ResultsBaP (0.05-1μM) activated SAPK and HAND1 without diminishing growth. TSC-to-TGC differentiation was assayed with increasingly accuracy for 2–4 N cycling nuclei and >4 N differentiating TGC nuclei, using ImageJ/FIJI, Gen 5, AIVIA, or CellPose AI software. The AIVIA and Cellpose AI software matches human accuracy. The lowest BaP effects on SAPK activation/HAND1 increase are >10-fold more sensitive than similar effects for mESC. RA induces 44–47% 1st lineage TGC differentiation, but the same RA dose induces only 1% 1st lineage mESC differentiation. DiscussionFirst, these pilot data suggest that mTSC can be used in high throughput screens (HTS) to predict toxicant exposures that force TGC differentiation. Second, mTSC differentiated more cells than mESC for similar stress exposures, Third, open source AI can replace human micrograph quantitation and enable a miscarriage-predicting HTS.

A novel model of sensorineural hearing loss induced by repeated exposure to moderate noise in mice: the preventive effect of resveratrol.

Sensorineural hearing loss (SNHL) induced by noise has increased in recent years due to personal headphone use and noisy urban environments. The study shows a novel model of gradually progressive SNHL induced by repeated exposure to moderate noise (8-kHz octave band noise, 90-dB sound pressure level) for 1 hr exposure per day in BALB/cCr mice. The results showed that the repeated exposure led to gradually progressive SNHL, which was dependent on the number of exposures, and resulted in permanent hearing loss after 5 exposures. Repeated exposure to noise causes a loss of synapses between the inner hair cells and the peripheral terminals of the auditory nerve fibers. Additionally, there is a reduction in the expression levels of c-fos and Arc, both of which are indicators of cochlear nerve responses to noise exposure. Oral administration of resveratrol (RSV, 50 mg/kg/day) during the noise exposure period significantly prevented the noise exposure-induced synapse loss and SNHL. Furthermore, the study found that RSV treatment prevented the noise-induced increase in the gene expression levels of the proinflammatory cytokine interleukin-1β in the cochlea. These results demonstrated the potential usefulness of RSV in preventing noise-induced SNHL in the animal model established as gradually progressive SNHL.

Differential transcriptome response of blood brain barrier spheroids to neuroinvasive Neisseria and Borrelia.

The blood-brain barrier (BBB), a highly regulated interface between the blood and the brain, prevents blood-borne substances and pathogens from entering the CNS. Nevertheless, pathogens like Neisseria meningitidis and Borrelia bavariensis can breach the BBB and infect the brain parenchyma. The self-assembling BBB-spheroids can simulate the cross talk occurring between the cells of the barrier and neuroinvasive pathogens. BBB spheroids were generated by co-culturing human brain microvascular endothelial cells (hBMECs), pericytes and astrocytes. The BBB attributes of spheroids were confirmed by mapping the localization of cells, observing permeability of angiopep2 and non-permeability of dextran. Fluorescent Neisseria, Borrelia or E. coli (non-neuroinvasive) were incubated with spheroids to observe the adherence, invasion and spheroid integrity. Transcriptome analysis with NGS was employed to investigate the response of BBB cells to infections. hBMECs were localized throughout the spheroids, whereas pericytes and astrocytes were concentrated around the core. Within 1 hr of exposure, Neisseria and Borrelia adhered to spheroids, and their microcolonization increased from 5 to 24 hrs. Integrity of spheroids was compromised by both Neisseria and Borrelia, but not by E. coli infection. Transcriptome analysis revealed a significant change in the expression of 781 genes (467 up and 314 down regulated) in spheroids infected with Neisseria, while Borrelia altered the expression of 621 genes (225 up and 396 down regulated). The differentially expressed genes could be clustered into various biological pathways like cell adhesion, extracellular matrix related, metallothionines, members of TGF beta, WNT signaling, and immune response. Among the differentially expressed genes, 455 (48%) genes were inversely expressed during Neisseria and Borrelia infection. The self-assembling spheroids were used to perceive the BBB response to neuroinvasive pathogens - Neisseria and Borrelia. Compromised integrity of spheroids during Neisseria and Borrelia infection as opposed to its intactness and non-adherence of E. coli (non-neuroinvasive) denotes the pathogen dependent fate of BBB. Genes categorized into various biological functions indicated weakened barrier properties of BBB and heightened innate immune response. Inverse expression of 48% genes commonly identified during Neisseria and Borrelia infection exemplifies unique response of BBB to varying neuropathogens.

Dwarf Galaxies Show Little ISM Evolution from z ∼ 1 to z ∼ 0: A Spectroscopic Study of Metallicity, Star Formation, and Electron Density

We present gas-phase metallicity measurements for 583 emission line galaxies at 0.3 < z < 0.85, including 388 dwarf galaxies with , and explore the dependence of the metallicity on the stellar mass and star formation (SF) properties of the galaxies. Metallicities are determined through the measurement of emission lines in very deep (∼7 hr exposure) Keck/DEIMOS spectra taken primarily from the HALO7D survey. We measure metallicity with three strong-line calibrations (O3Hβ, R23, and O3O2) for the overall sample, as well as with the faint [Ne iii]λ3869 and [O iii]λ4363 emission lines for 112 and 17 galaxies where robust detections were possible. We construct mass–metallicity relations (MZR) for each calibration method, finding MZRs consistent with other strong-line results at comparable redshift, as well as with z ∼ 0 galaxies. We quantify the intrinsic scatter in the MZR as a function of mass, finding it increases with lower stellar mass. We also measure a weak but significant correlation between increased MZR scatter and higher specific star formation rate (SFR). We find a weak influence of SFR in the fundamental metallicity relation as well, with an SFR coefficient of α = 0.21. Finally, we use the flux ratios of the [O ii]λ λ 3727,3729 doublet to calculate gas electron density in ∼1000 galaxies with as a function of redshift. We measure low electron densities (n e ∼ 25 cm−3) for z < 1 galaxies, again consistent with z ≈ 0 conditions, but measure higher densities (n e ∼ 100 cm−3) at z > 1. These results all suggest that there is little evolution in star-forming interstellar medium conditions from z ∼ 1 to z = 0, confirmed with a more complete sample of low-mass galaxies than has previously been available in this redshift range.

AZD4573 in Combination with CHOP Increases Combination Benefit in Preclinical Peripheral T-Cell Lymphomas Models

Peripheral T-cell Lymphoma (pTCL) make up about 10% of non-Hodgkin's lymphoma in the United States. Patients with relapsed/refractory pTCL have limited treatment options and poor outcomes to standard of care therapy. Current standard of care for pTCL revolves around the chemotherapy regimens CHOP/E and for CD30-postive pTCLs, brentuximab vedotin is approved. CDK9 regulates transcription elongation through phosphorylation of RNA polymerase II. AZD4573 is a highly potent and selective CDK9 inhibitor, acute inhibition with AZD4573 downregulates short-lived proteins such as MCL-1, BFL-1, and c-MYC, which are frequently overexpressed in haematologic tumours. It has been previously shown that the expression pattern of the anti-apoptotic BCL-2 family members in pTCL cell line models closely resembled the expression patterns in pTCL patient samples (Koch et al. 2019). Expression and dependencies of the anti-apoptotic BCL-2 family members is highly heterogeneous in pTCL; however MCL-1 is the most universally expressed BCL-2 family member. Using the MCL-1 inhibitor AZD5991, we have shown statistically significant benefit in survival when combined with CHOP in 2 MCL-1 dependent preclinical pTCL PDX models (Koch et al. 2019). In addition to MCL-1, we have previously reported the importance of the anti-apoptotic protein BFL-1 in mediating cell survival in NHL, including a subset of pTCL (Boiko et al 2021). Consistent with these findings, AZD4573 treatment exhibited a range of activity across the panel of 18 human TCL cell lines, in a 6-hour caspase-3/7 activation assay. 14 of the cell lines were sensitive, having EC 50 values &amp;lt; 100 nM, and 13 reached a max caspase-3/7 activation of greater than 40%. pTCL cell lines that responded to AZD4573 treatment including ALCL, NK-TCL, and PTCL-NOS and CTCL subtypes. Acute AZD4573 treatment of pTCL cell lines resulted in decreased p-SerRNApoll II and reduced levels of c-MYC and MCL-1 protein levels. To determine if MCL-1 or c-MYC was driving the apoptotic phenotype, we used ribonucleoprotein (RNP) mediated CRISPR knock out (KO) of MYC and MCL1 genes. While pTCL cell lines were dependent on c-MYC and MCL-1 after long term KO, only MCL-1 KO impaired AZD4573 treatment, suggesting that AZD4573 efficacy is mediated through MCL-1, in ALCL pTCL cell lines tested. To determine if combining AZD4573 with CHOP improved efficacy, we tested 5 pTCL cell lines in a 6x6 combination dosing matrix and assessed for viability after 24-72 hours using RealTime-Glo after 18hr exposure to CHOP and AZD4573 added for the last 6hrs. Adding AZD4573 treatment to CHOP schedule in vitro increased the combination benefit in pTCL ALCL cell lines that show MCL-1 dependency, but not in CTCL cell line which show a BCL-xL dependency and resistance to AZD4573. CHOP treatment in vitro resulted in a decrease in c-MYC levels at 24-48 hours, but not MCL-1 suggesting that combination benefit may be driven through decreased c-MYC levels, as KO of c-MYC resulted is loss of cell viability in these models. These data suggested that treatment with AD4573 either as a monotherapy or in combination with CHOP, would be an effective therapeutic strategy in pTCL. AZD4573 monotherapy is currently being evaluated in a phase 2 study (NCT05140382) to assess the efficacy, safety, and PK in patients with relapsed/refractory pTCL.

Live Microalgae-Based Diets as Enrichment to Improve the Nutritional Profile of the Calanoid Copepod Acartia tonsa (Dana, 1849) Nauplii

Most emerging species in marine aquaculture and the aquarium industry have a sensitive and small-mouthed larval stage, and their culture is very challenging due to a lack of appropriate early feeding protocols. The use of copepods has been widely recognized as a good alternative to traditional fish live feeds (rotifers and Artemia spp.), especially for new species targeted for the multibillion-dollar marine aquarium trade. However, most copepod culture trials are focused on biomass production, while their nutritional requirements and enrichment protocols remain scarcely known. The main objective of this study was to determine the dietary contribution of three microalgae-based diets, provided as a mono R (Rhodomonas salina) or binary I–R (Isochrysis galbana + R. salina) and T–R (Tetraselmis suecica + R. salina), on the biochemical composition (proximate and fatty acids (FAs)) and survival of the calanoid copepod Acartia tonsa (nauplii) versus the conventional rotifer Brachionus plicatilis throughout 96 hr exposure. Both live preys were characterized by the highest protein and total n-3 long-chain polyunsaturated FAs (LC-PUFAs) content when fed with the binary diet I–R compared to other treatments, although the nutritional value of A. tonsa nauplii was always much higher compared to B. plicatilis. In general, there was a wide difference in proximate and FAs composition between the two preys, denoting A. tonsa as better live feed in terms of capacity to retain n-3 LC-PUFAs, especially eicosapentanoic acid (20 : 5n-3) and docosahexanoic acid (22 : 6n-3). The present study highlights the nutritional profile of enriched A. tonsa nauplii and contributes to the production of high-quality live feeds, which may be able to reach the nutritional needs of new marine fish species during their larval development, as well as contributing to the improvement of A. tonsa culture.

Toxicological Profile of Pomegranate (Punica Granatum) Peel Extract and Histopathological Assessment in Zebrafish (Danio rerio): An In-Vivo Study

Background: Fruit – by - product includes peels, seeds, leaves, residual pulp, stems and discarded pieces from a variety of sources. Pomegranate (Punica granatum) peel is a good source of bioactive compounds, antioxidants, nutraceuticals, and functional properties and there is a healthy trend towards by-product utilization and value addition. However, its toxicity and its adverse effects were not intensively studied. Objective: This study aimed to examine the In-vivo toxicity of Pomegranate Peel Powder (PPP) extract and histopathological assessment using zebrafish (Danio rerio). Methods: Decoction (Aqueous) by Soxhlet method was used for extraction from Pomegranate Peel Powder (PPP). Dense extract was used to study toxicity level and it was assessed using Dose Dependent Toxicity Assessment (DDTA) with Zebrafish. The mature Zebrafish were divided into eight groups (A, B, C, D, E, F, G, and control) based on their average body weight, with eight fishes in each tank. Fish groups (8 fishes/concentration) were treated to different doses and concentrations of Pomegranate Peel Powder (PPP). Fish mortality was monitored and recorded after 24, 48, 72, and 96 hours. After acute toxicity analysis, H &amp; E staining was performed to analyse the zebrafish brain. At least 3 fish from each group were taken and analysed for histopathological scoring. Result: At 24 hr and 96 hr exposure periods, the lethal dosage, to kill 50% of test fishes, was 800 mg/L. Fish treated with 200 mg/L dosage had a score grade of 1 and showed no toxic pathological changes when compared to 400 and 800 mg/L doses because they considerably had decreased pathological scores of neuronal damages, which was equivalent to the control group. Zebrafish treated with 12.5 – 200 mg/L showed no toxic effect in the brain of fish, which was comparable with the control. Conclusion: The current study showed that the No-Observed Adverse Effect Level (NOAEL) is evaluated to be 200 mg/L dosage. Thus, PPP has less toxicity, and its use is suggested with potential applications against diseases.

An investigation into the use of riverine mesocosms to analyse the effect of flow velocity and recipient textiles on forensic fibre persistence studies

Textile fibre evidence can provide important activity level information in criminal cases. To date, very few studies have investigated fibre persistence on fabrics exposed to aquatic conditions, even though items of evidence and victim’s bodies can regularly be found in aquatic environments. This lack of research on whether fibres (and other trace evidence) persist on evidence submerged in water, has shown to impact practice as it is reported that crime scene examiners do not attempt to recover this evidence, due to the belief that it would not be present. The dynamic nature of aquatic environments mean that the studies are difficult to conduct in situ and variables, such as water flow rate are not possible to control and thought to be difficult to monitor. To address these challenges, artificial streams (also known as mesocosms) were employed in this study to investigate the persistence rate of polyester fibres on different fabric types (Woollen/nylon mix carpet, 100% polyester fleece, and 95% polyester/5% elastane sports vest) for a four week exposure time (1, 8, 24, 48, 120, 168, 264, 336, 504 and 672 hrs). The effect of water flow rate on the persistence of fibres was investigated by conducting the experiment with two flow velocities; 'high' (∼2.75 L/s) or 'low' (∼0.7 L/s). Significant differences between textile type were seen at 504 hrs under low flow conditions and 8, 24, 168 and 264 hrs under high flow conditions. When comparing flow velocities, a significant difference was seen at 1 hr exposure for the fleece textile only, indicating that the two flow rates used in this study do not significantly affect fibre persistence. Initial loss rates were highest for the first hour of submergence for the carpet, fleece and sports vest. Fibre persistence rates were highest on the carpet, followed by fleece and then sports vest. Persistence rates remained mostly constant after 24 hrs for all textiles but with redistribution of fibres between textiles being seen after this exposure time. The use of artificial flumes in this study provided a balance between realistic experimentation and a controlled study; key experimental variables could be continously and safely monitored. This study provides the first fibre persistence data in river type environments and proposes a new method for testing persistence in aquatic environments. This approach is not limited to fibres evidence and could be employed for other evidence such as glass, pollen, fingerprints and DNA.

CYTOTOXIC ACTIVITY OF BASIL SEEDS( Ocimum baslicum L) EXTRACTS ON SOME BREAST CANCER CELL LINES ( IN VITRO)

In this study, four types of basil seed extracts were used, being cold aqueous extract, hot aqueous extract, petroleum ether extract, and methanolic extract.Nine concentrations (10000, 5000, 2500, 1250, 625, 312.56, 156.25, 78.125, 39.0, 0.0) µg/ml were used to study the extracts cytotoxicity against two breast cancer cell lines MCF7 and AMJ13 beside REF cell line as normal cells. The methanol extract showed the highest inhibition rate of 64.4% on MCF7 cell line at concentration of 1250 µg/ml and 42.4% on AMJ13 cell line at a concentration of 39.0 µg/ml with significant difference as compared to control sample during the 72hr exposure period. While the petroleum ether extract showed a lower inhibition rate of 16.02% at a concentration of 78.1 µg/ml on MCF7 cell line and 35.3 % at a concentration of 312.5 µg /ml on AMJ13 cells during a 72hr exposure period, compared with the two aqueous extracts which showed a slight effect compared to the control. The cold aqueous extract showed the slight effect of 24.4% at a concentration of 5000 µg/ml on AMJ13 cell line and no toxicity was shown on MCF7 cells. All extracts showed no effect on REF normal cells. In all effective concentrations the basil seed extracts caused a damage to the DNA that cannot be repaired, and thus the cells are heading to programmed death. This effect on the genetic material was studied using the comet assay and mitotic index.

Effects of acute exposure to chlorfenapyr on hepatic enzyme activities and serum lipid profile of African catfish, Clarias gariepinus (Burchell 1822)

The effects of acute exposure to chlorfenapyr on hepatic enzymes and lipid profile of Clarias gariepinus juveniles were investigated following standard protocols. Test organisms were exposed to chlorfenapyr concentrations of 5, 7, 9, 11 and 15 mgL-1 for 96 hr exposure period. After exposure, peripheral blood was collected through the caudal vein into plain sterilised tubes and allowed stand for 1 h for clot to form. The clotted blood was then centrifuged at 3000 rpm for 10 min and the serum obtained was used for all the biochemical assay. Cross-sections of the gills were examined for histological aberrations. Results showed significant increase in enzymatic activities of Aspartate amino transferases (AST), Alanine amino transferases (ALT) and Alkaline phosphatase (ALP) (p&lt; 0.05) when compared with control. Lipid profile results showed significant (p&lt;0.05) increase in Total cholesterol (TC) and Low- density lipoprotein-cholesterol (LDL-cholesterol) in all treated groups when compared with the control. Significant (p&lt;0.05) reduction in high density lipoprotein- cholesterol (HDL-cholesterol) and triacylglycerides in all treated groups compared to the control was also recorded. Such alterations in biochemical parameters did not show any relationship with gills histology as the cross-section of the gills provided no evidence of aberrations. The results suggest that exposure to acute concentrations of chlorfenapyr can alter liver enzyme activities and serum lipid profile initiating a jump in the energy requirement of the exposed organism.

A single exposure to sub-lethal concentrations of a glyphosate-based herbicide or fluoxetine-based agent on growth performance in Nile tilapia

ABSTRACT The aim of the present study was to determine e whether a single acute 96 hr exposure of a glyphosate-based herbicide (GBH) to Nile tilapia fingerlings affected growth performance during the first 90 days of culture. This association was considered as GBH increases serotoninergic activity that affect fish anorexically. Although these findings were based upon chronic investigations, this study was designed to examine whether a single, acute, but excessive concentration GBH might impair growth performance in fish. In parallel, fish were also exposed to fluoxetine (FLU), a drug that selectively inhibits the reuptake of serotonin in brain synapses, leading to increased serotoninergic activity. Data demonstrated a decreased growth performance in fingerlings exposed to GBH or FLU compared to unexposed fingerlings. In fact, FLU-exposed fingerlings exhibited lower average weight and length, diminished weight gain, which resulted in lower final biomass. GBH-exposed fish, despite displaying a lower mean body weight, exhibited a biomass similar to biomass on controls. These body weight differences were noted after 30–60- and 90-day growth period in clean water. In an aquaculture context, these observed changes may be considered harmful to the production or economic performance of large-scale farming as currently practiced in tilapia farming.

Toxicity and effects on anuran tadpole metamorphosis of the anthranilic diamide insecticides chlorantraniliprole and cyantraniliprole

ABSTRACT The present study examined the acute and chronic toxicity attributed to commercial formulations of the anthranilic diamide insecticides chlorantraniliprole (CHLO) and cyantraniliprole (CYAN) on the neotropical amphibian species Rhinella arenarum, Rhinella fernandezae and Scinax granulatus. The median lethal concentrations obtained after 96 hr exposure (96 hr-LC50) were generally greater than 100 mg/L, except for stage 25 S. Granulatus, which were the most sensitive animals tested with a 96 hr-LC50 value of 46.78 mg/L. In subchronic exposures of R. arenarum, the 21day-LC50 were 151.4 mg/L for CHLO and >160 mg/L for CYAN, the weight gain of the tadpoles during this period not being markedly affected in both cases. Finally, when tadpoles of R. arenarum were exposed to CHLO throughout the metamorphic process, an inverted U-shaped non-monotonic dose-response relationship was observed between exposure concentrations and both % of individuals transiting between stage 39 and 42 and the time required to accomplish this. Data obtained raise the hypothesis of an effect of CHLO on the hypothalamic-pituitary-thyroid (HPT) axis, either directly or through an interaction with the stress-hormone system, as metamorphic progression from stage 39 to S42 occurs under the strict control of thyroid hormones. These observations are important as the anthranilic diamide insecticides are not currently known as endocrine disruptors. Further investigations are needed to clarify the pathways leading to these effects and examine whether environmentally-relevant aquatic concentrations of anthranilic diamides might be impacting amphibian populations in the wild.

Effects of Chloramine T on zebrafish embryos malformations associated with cardiotoxicity and neurotoxicity

ABSTRACT Chloramine T, a sodium p-toluene sulfonchloramide, is known to possess a wide spectrum of biocidal activity and is employed as a disinfectant in fish farms to treat bacterial infections. Although Chloramine T may effectively combat pathogens, the sublethal and lethal effects and changes in acetylcholinesterase (AChE) activity remain poorly elucidated using Danio rerio (zebrafish) embryos. Zebrafish is considered a model organism for toxicant screening research and exhibits mammalian-like physiological responses when exposed to environmental pollutants. The aim of this study was to (1) determine LC50 of Chloramine T after 96 hr exposure, (2) verify disinfectant effects on developmental morphology, and (3) evaluate the disinfectant effects on AChE activity in zebrafish embryos. Chloramine T exposure was performed using 16, 32, 64, 128, or 256 mg/L concentrations. The mortality LC50 values were 143.05 ± 3.11 and 130.97 ± 7.4 mg/L at 24 and 96 hr, respectively. Data demonstrated delayed hatching, reduced heartbeats, cardiac edema, and equilibrium disruption of hatched larvae throughout embryonic development. In addition, Chloramine T inhibited AChE activity at 64 or 128 mg/L after 96 hr treatment, corroborating the sub-lethality results observed in zebrafish embryo development and demonstrating an equilibrium disruption in zebrafish larvae.

Corrosion resistance of amorphous AlPO4 coating in salty atmospheres

AbstractThe objective of the present study was to introduce a cost‐effective and environmentally friendly coating to improve the corrosion resistance of the structures located in salt water. The coating solution, based on amorphous aluminum phosphate composition, was synthesized by sol–gel process and applied to AISI 304 stainless steel by dip coating technique. X‐ray diffraction, scanning electron microscopy, and energy dispersive X‐ray spectroscopy analyses were employed to investigate the phase composition and morphology of the coating. Corrosion behavior of the uncoated and coated samples was investigated using standard salt spray test, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS) in 3.5 wt.% NaCl solution. Salt spray test results for the bare substrate revealed a corrosion rate of six‐time greater than that of the coated surface after 168 hr exposure time. Electrochemical test results declared that the amorphous AlPO4 coating decreased the corrosion current density of the AISI 304 stainless steel by 10 orders of magnitude. Furthermore, according to the corresponding EIS measurements, the coated surface exhibited a superior anti‐corrosion performance than uncoated sample. Overall, the results declared that the amorphous AlPO4 coating could be a good choice for surface protection of stainless steel against electrochemical corrosion in salty environments.