Lethal Dose Research Articles

Effect of Cherenkov light on cell survival in x-ray irradiation of LINAC based on Monte Carlo simulation and cell survival measurements

Cherenkov radiation is emitted during x-ray irradiation in a linear accelerator (LINAC). Cherenkov light contains many short wavelength components, including ultraviolet (UV) light, which is well-known for its bactericidal effects. A similar phenomenon is probable for human cancer cells. To assess the effect of Cherenkov light on cell death in x-ray irradiation, we employed simulations and UV cell survival data. We measured the survival rates of HeLa cells exposed to 254 nm (UVC) and 310 nm (UVB) light to determine the 50% lethal dose (LD50) required to kill 50% of the cells. For other wavelengths, we utilized literature values to establish the relationship between wavelength and LD50. Due to the broad range of the Cherenkov light spectrum, we need LD50 as a function of wavelength to estimate cell survival solely from Cherenkov light. A Monte Carlo simulation was used to calculate the fluence distribution of Cherenkov light in a 300 mm3phantom comprised of soft tissue, both with and without absorption of visible light. The latter scenario is considered to be most influenced by Cherenkov light. By combining the fluence distribution and the wavelength-LD50 relationship, we determined the distribution of the survival rate. Our findings indicate that, in the absence of absorption, a radiation dose of approximately 90 Gy or greater is necessary for Cherenkov light to have any effect. As a result, the impact of Cherenkov light on cell survival can be considered negligible for typical dose of 2 Gy.

Non-food bioactive products as pesticide candidates: Preparation and agrochemical activities of novel nonivamide ether derivatives containing the isoxazole fragment

To explore non-food natural products as pesticide candidates for agricultural application, a series of nonivamide ether derivatives (3a–3q) containing the isoxazole fragment were constructed from an alkaloid nonivamide isolated from Capsicum annuum L. Against Mythimna separata Walker, the final corrected mortality rate (FCMR) of 3b at 1.0 mg/mL was 62.9 %, which was 2.0 times of that of nonivamide. Against Aphis citricola Van der Goot, the median lethal dose (LD50) value of 3d was 0.049 μg/nymph, which was 12.4 times of that of nonivamide. Against Plutella xylostella Linnaeus, the median lethal concentration (LC50) value of compound 3b was 0.793 mg/mL, which was 9.2-fold of that of nonivamide. Furthermore, the enzymes activity changes of carboxylesterase (CarE), glutathione S-transferase (GST), and mixed function oxidase (MFO) over time in P. xylostella treated with 3b were evaluated. We hope that this study will establish a robust groundwork for structural modification of nonivamide derivatives and their potential utilization as plant-based insecticides.

Assessing the dual toxicity of HfO2 nanoparticles and quinalphos on Pila virens

Pila virens (P. virens) is an edible freshwater snail, widely distributed in Asia and Africa. P. virens is used as one of the most promising model organisms for monitoring environmental contamination in aquatic ecosystems. The physiological responses to the contaminants such as pesticides and nanomaterials are inadequate, especially in relation to the effects of co-exposure. In this work, we have investigated on the noxious effects of co-exposure between an organophosphorus pesticide, quinalphos and hafnium oxide nanoparticles (HfO2NPs) on the antioxidant responses of P. virens. Phase pure forms of HfO2NPs (monoclinic, P21/c) were obtained by sol-gel method. The crystallinity, structure and surface morphology were analysed with various spectroscopic methods like powder X-ray, Fourier-transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), High Resolution Scanning Electron Microscope (HR-SEM) and Transmission Electron Microscope (TEM). P. virens after exposure for 96 h to the different concentrations of quinalphos (0.25–2.25 mg/mL) and HfO2NPs (10–50 mg/mL), the median lethal concentration (LC50) was determined to be 1.159 mg/mL and 11.47 mg/mL, respectively and show a significant fatal effect against the snail. The P. virens were exposed to sub-lethal concentrations of LC25 (0.57 mg/mL quinalphos and 5.73 mg/mL HfO2NPs) individually and in combination as a binary toxicity (quinalphos + HfO2NPs), (0.57 mg/mL + 5.73 mg/mL) for 24 and 48 h. Further, the antioxidant responses were assessed which included catalase (CAT), glutathione sulfo-transferase (GST), and malonaldehyde (MDA) activity in the group exposed to quinalphos and HfO2NPs exhibited to show an enhancement in their activity in comparison to controls after 24 and 48 h and revealed that 48 h exposure has significant impact. These results provide a valuable insight towards increased awareness of the physiological defences of P. virens after co-exposure to quinalphos and HfO2NPs in aquatic ecosystem.

A novel encapsulation method for lemongrass essential oil in nanoemulsion and SiO2 nanoparticles against the storage mite Aleuroglyphus ovatus (Acari: Acaridae)

Lemongrass essential oil (LEO), which is extracted from Cymbopogon citratus, has emerged as a promising alternative to traditional synthetic pesticides. In the present study, we fabricated pure LEO and its nanomaterials (nanoemulsion [NE] and SiO2 nanoparticles [NPs]) and investigated their acaricidal effects on Aleuroglyphus ovatus (Acari: Acaridae), a common storage pest mite. A loading capacity (LC) of 57.45% was obtained, showing successful encapsulation of LEO in SiNPs. The contact mortality, fumigant mortality, ovicidal activity, repellent activity, and toxic effects of LEO on A. ovatus were investigated. The median lethal concentration (LC50) values of contact mortality of LEO, LEO-NE, and LEO-SiNPs against adult mites were 0.067, 0.053, and 0.019 mg/cm2, respectively, after 24 h of exposure. Similarly, the corresponding LC50 values of fumigant activity were 0.044, 0.096, and 0.067 mg/cm3, respectively. All products had greater contact and fumigant effects on nymphs and larvae than they did on adults. After 5 days of exposure to the products, LEO-NE and LEO-SiNPs had greater inhibitory effects on hatching than did pure LEO. LEO-SiNPs exhibited a rapid and significant repellent effect at 3 h (82.22%) and were effective even after 24 h (35.56%), indicating their persistent and long-term acaricide activity. A study of toxicity symptom revealed two different manifestations of toxicity in mites after exposure to these products (knock-down type and immobilized type). Taken together, these findings suggest that LEO and its nanomaterials exhibit significant acaricidal activity against A. ovatus.

Control efficacy and joint toxicity of broflanilide mixed with commercial insecticides to an underground pest, the black cutworm in highland barley.

The highland barley, Hordeum vulgare L., is a staple food crop with superior nutritional functions in Xizang, China. It is often damaged by the black cutworm, Agrotis ipsilon (Hufnagel), which is an underground pest and difficult to effectively manage. To introduce a novel insecticide with unique mode of action, broflanilide (BFL) and its binary mixtures with chlorantraniliprole (CAP), fluxametamide, β-cypermethrin or imidacloprid were screened out as seed treatment to control black cutworm in highland barley in the present study. In the laboratory bioassays, BFL had outstanding insecticidal activity to black cutworm with a median lethal dose (LD50) of 0.07 mg kg-1. The mixture of BFL × CAP at the concentration ratio of 7:40 exhibited the highest synergistic effect with a co-toxicity coefficient of 280.48. In the greenhouse pot experiments, BFL and BFL × CAP seed treatments at 8 g a.i. kg-1 seed could effectively control black cutworm, with a low percentage of injured seedlings <20% and high control efficacies of 93.33-100% during a period of 3-12 days after seed emergence. Moreover, BFL and BFL × CAP seed treatments could promote the seed germination and seedling growth of highland barley at the tested temperatures of 15, 20 and 25 °C. Our results indicated that BFL and BFL × CAP were effective and promising insecticides as seed treatment to control black cutworm in highland barley. © 2024 Society of Chemical Industry.

Holistic characterization analysis of tar waste content from gasification process at Surakarta landfill

Surakarta is facing serious problems related to waste management at the Putri Cempo landfill. PT. Solo Citra Metro Plasma Power with the Surakarta city government built a waste power plant installation with gasification technology. Tar waste is a gasification liquid product that is dangerous if not managed. This study aimed to determine the heavy metal content and toxicity level of gasified tar waste using the atomic absorption spectrometry (AAS) and lethal dose-50 (LD&lt;sub&gt;50&lt;/sub&gt;) acute toxicity test. The parameters of heavy metals tested are lead (Pb), copper (Cu), iron (Fe), zinc (Zn), and total chromium (Cr). In the LD&lt;sub&gt;50&lt;/sub&gt; test, the animals were divided into 5 groups, namely 1 control group and 4 groups with doses of 0.50 mL, 1 mL, 2 mL, and 4 mL. The results showed that the tar contained 17.4 mg/L of iron, 3.5 mg/L of zinc, and &amp;lt;0.01 mg/L of lead, copper, and chromium. Acute toxicity tests did not cause death in the animals but still showed toxic symptoms, so the LD&lt;sub&gt;50&lt;/sub&gt; value is declared pseudo. The content of some heavy metals in tar is within safe limits and the level of toxicity is relatively harmless.

Shikonin Inhibits Oral Cancer Progression Through Suppression of Metastasis and Angiogenesis and Induction of Autophagy and Apoptosis

Background: Shikonin, a compound extracted from Lithospermum erythrorhizon, has demonstrated therapeutic effects on cancer; however, its effects on oral cancer remain unclear. Objectives: This study aimed to explore the therapeutic value of shikonin for the treatment of oral cancer. Methods: MTT, colony formation, and Transwell assays were employed to evaluate the inhibitory effects of shikonin on the proliferation and migration abilities of human oral cancer cell lines (SCC-4 and SAS). Apoptosis and cell viability were assessed using the TdT-mediated deoxyuridine triphosphate-biotin nick end-labeling (TUNEL) assay. To investigate the potential anticancer mechanisms of shikonin, RNA sequencing, quantitative PCR, and western blotting were performed to analyze changes in the expression levels of oral cancer cell-related genes and proteins (matrix metalloproteinases-2 (MMP-2), matrix metalloproteinases-9 (MMP-9), VEGF-A, VEGF-C, Beclin-1, autophagy-related genes (ATG5), and light chain-3 (LC-3)). Additionally, animal xenograft experiments were conducted to examine the in vivo antitumor effects of shikonin. Results: The findings revealed that the external application of shikonin specifically targeted oral cancer cells without affecting normal cells and led to a dose-dependent inhibition of their growth. Even at non-lethal doses, shikonin effectively suppressed the production of metalloproteinases, thereby inhibiting cancer cell migration and wound healing. Furthermore, shikonin treatment reduced levels of tumor progression factors, such as vascular endothelial growth factor (VEGF)-A and VEGF-C, which are released during the early stages of cancer cell angiogenesis and lymphangiogenesis. Meanwhile, higher doses of shikonin induced cell autophagy and activated proteins such as ATG-5, LC-3B, and Beclin-1. At lethal doses, shikonin further decreased mitochondrial membrane potential, released calcium ions, and triggered apoptotic pathways. However, the administration of a calcium ion chelator (BAPTA-AM) inhibited shikonin-induced apoptosis. Conclusions: These results demonstrate that shikonin induces autophagy and activates apoptotic pathways in oral cancer cells. Shikonin treatment significantly inhibited oral cancer growth and induced apoptosis in a rat model. In conclusion, shikonin effectively inhibited oral cancer cell growth, metastasis, and the expression of tumor progression-related proteins. Given the ease of drug delivery to the affected area in oral cancer, shikonin holds substantial potential for future applications that may improve patient recovery and enhance cure rates.

Induction of antiherbivore defense responses in poplars using a methyl jasmonate and mesoporous silica nanoparticle complex.

Poplar in China has long been plagued by the fall webworm Hyphantria cunea. Enhancing plant immunity using chemical elicitors is an environmentally friendly approach to pest control. The phytohormone methyl jasmonate (MeJA) can stimulate the chemical defenses of poplars against herbivores but has been shown to have limited efficacy in practice. Here, we studied the effects of a MeJA and mesoporous silica nanoparticle (MSN) complex (MeJA@MSN) regarding the induction of poplar resistance to H. cunea, which may provide strategies for the effective use of MeJA. The silicon-based phytohormone complex (MeJA@MSNs) exhibited excellent biological and physiochemical properties, such as excellent biocompatibility and plant tissue transportability. The changes in metabolites in poplar leaves induced by MeJA, MSNs, and MeJA@MSNs were investigated by metabolic analysis. MeJA@MSNs led to highly potent induced resistance along with elevated salicylaldehyde content, which increased with the dose administered. The salicylaldehyde metabolite showed a strong antifeedant effect on H. cunea larvae at a dosage of 1 μg, with the 50% lethal dose being 20.4 μg/mg. Furthermore, transcriptional analysis showed that MeJA@MSNs upregulated key genes in biosynthetic pathways more than MeJA and MSNs. Our results show that MeJA and MSNs interact positively in poplar, leading to salicylaldehyde accumulation and increased induced resistance to H. cunea, providing new insights into the underlying resistance mechanisms induced by MeJA@MSNs. © 2024 Society of Chemical Industry.

Elucidation of molecular mechanisms, pathways, and diseases modulated by arsenicals through toxogenomics and multi-omics analysis

Arsenic compounds exist in inorganic and organic forms with inorganic form confirmed as a potent carcinogen. Toxogenomics and multi-omics analysis were used to explore the molecular mechanisms of carcinogenecity induced by arsenicals. Comparative toxogenomics revealed sodium arsenite and arsenate as the most toxic arsenicals to humans, interacting with various genes and altering gene expression through mRNA binding proteins. Both metalloids were classified as Class II toxins by the ProTox II prediction tool, with a lethal dose (LD50) of 149mg/kg body weight. The most frequently interacting genes were HMOX1, CAT, NFE2L2, CASP3, MAPK1, CXCL8, PARP1, TNF, and PYGM. Analysis of TCGA pan-cancer data revealed that 46% of hepatocellular carcinoma patients exhibited alterations in the genes HMOX1, CAT, NFE2L2, CASP3, MAPK1, CXCL8, PARP1, TNF, and PYGM, suggesting their significant role in the development of this disease. The alteration in the gene list decreased the overall patient survival but insignificantly in the Kaplan-Meier curves revealing insignificant role in survival. GSEA suggested significant enrichment of the gene list in pathways involved in the G2M checkpoint, apoptosis, hypoxia, TNFA signaling via NFKB, PI3K AKTMTOR signaling, P53, IFN gamma and inflammatory response pathways revealing the involvement of these pathways. Ten microRNAs (miRNAs) regulated the expressions of the genes involved in the above-mentioned pathways with the significant enrichment in miR-21-3p, miR-206 and mir486a-5p. The relevant pathway and graphical representation of the network of miRNA-target interactions identified by the enrichment analysis along with disease ontologies were predicted. This study will be helpful insight into setting of laboratory experiments.

Combined transcriptome and metabolome analysis reveals the mechanism of high nitrite tolerance in freshwater mussel Anodonta woodiana

Nitrite contamination and stress on aquatic organisms are increasingly emphasized in freshwater ecosystems. Freshwater bivalves exhibit high tolerance to nitrite; however, the underlying mechanism is unknown. Accordingly, this study investigated the tolerance mechanism of the globally occurring freshwater bivalve Anodonta woodiana. A. woodiana were exposed to nominal concentrations of 0, 250, 500, 1000, 2000, and 4000 mg/L nitrite for 96 h to calculate the 96-h median lethal concentration (96-h LC50). A combined transcriptome and metabolome analysis of the hemolymph (the most vital component of the bivalve immune system) was performed after exposing A. woodiana to 300 mg/L nitrite (approximately half the 96-h LC50) for 96 h. The 96-h LC50 of nitrite in A. woodiana was 618.7 mg/L. Transcriptome analysis identified 5600 differentially expressed genes (DEGs) primarily related to ribosomes, lysosomes, DNA replication, and nucleotide excision repair. Metabolome analysis identified 216 differentially expressed metabolites (DEMs) primarily involved in biosynthesis of amino acids, 2-oxocarboxylic acid metabolism, protein digestion and absorption, aminoacyl-tRNA biosynthesis, nucleotide metabolism, ABC transporters, and valine, leucine and isoleucine degradation. Combined transcriptome and metabolome analysis revealed that DEGs and DEMs were primarily associated with nucleotide (purine and pyrimidine) and amino acid metabolism (including aminoacyl-tRNA biosynthesis, cysteine and methionine metabolism, arginine and proline metabolism, and valine, leucine and isoleucine degradation) as well as the immune system (necroptosis and glutathione metabolism). This study is the first to describe the high tolerance of A. woodiana to nitrite and elucidate the molecular mechanisms underlying high nitrite tolerance in mussels.

The actions of varenicline on alkaloids from Conium maculatum (poison hemlock), Lupinus sulphureus (sulphur lupine) and Nicotiana glauca (tree tobacco).

Evidence-based therapies to manage the clinical signs of intoxication caused by toxic plants in livestock are lacking. For that reason, the aim of this work was to develop a drug-based intervention for the management of clinical signs of piperidine alkaloid intoxication in livestock. The actions of anabasine, coniine, γ-coniceine, and two total alkaloid extracts from Lupinus sulphureus were compared in the presence and absence of the nicotinic acetylcholine receptor partial agonist varenicline in RD cells, mice and goats. Pretreatment of RD cells with 10.0μM varenicline significantly shifted the anabasine fifty percent effective concentration (EC50) value to a greater concentration and blocked the response of the cells to coniine. γ-coniceine did not have any effect on RD cells as measured by membrane potential sensing dye. Swiss Webster mice median lethal dose (LD50) values for anabasine, coniine, γ-coniceine were 1.5, 5.5, and 3.7mg/kg respectively, and pretreatment with 10.0mg/kg i. p. dosed varenicline shifted the LD50 values to 4.2, 9.1, and 4.3mg/kg respectively. The rodent LD50 value of the Pendelton, WA L. sulphureus quinolizidine alkaloid extract was shifted to a lesser concentration by varenicline while the Ritzville, WA L. sulphureus piperidine alkaloid extract was shifted to a greater concentration by varenicline. The clinical signs of intoxication in goats orally dosed with Conium maculatum were exacerbated by 0.5, 1.0 and 10.0mg/kg i. v. dosed varenicline. These results suggest that varenicline was effective at shifting piperidine alkaloid EC50 values in RD cells and increasing piperidine but not quinolizidine alkaloid LD50 values in mice and was not useful at managing the clinical signs of poison hemlock intoxication in goats.

Integrating pyriproxyfen into the incompatible insect technique enhances mosquito population suppression efficiency and eliminates the risk of population replacement.

The incompatible insect technique (IIT) has been used for Aedes mosquito population suppression to curb the transmission of dengue. However, its wide application is limited owing to the low output of male mosquitoes and the risk of population replacement from the release of fertile Wolbachia-infected females. This study aims to improve IIT efficiency for broader adoption. We assessed the impact of 10% pyriproxyfen (PPF) sticky powder exposure on Wolbachia (from Culex molestus)-transinfected Aedes albopictus Guangzhou line (GUA line) (GC) mosquitoes. We found that the exposure caused chronic toxicity in adult mosquitoes without affecting the cytoplasmic incompatibility (CI)-inducing capability of males. The PPF-contaminated GC females exhibited significant sterilization and the ability to disseminate lethal doses of PPF to breeding sites. Subsequently, we conducted a field trial combining PPF with IIT aiming to suppress the Ae. albopictus population. This combined approach, termed boosted IIT (BIIT), showed a notable enhancement in population suppression efficiency. The improved efficacy of BIIT was attributed to the dispersion of PPF particles in the field via the released PPF-contaminated male mosquitoes. During the BIIT field trial, no Wolbachia wPip-positive Ae. albopictus larvae were detected, indicating the effective elimination of the risk of Wolbachia-induced population replacement. Additionally, the field trial of BIIT against Ae. albopictus resulted in the suppression of the nontarget mosquito species Culex quinquefasciatus. Our results highlight the remarkable efficiency and feasibility of combining IIT with PPF in suppressing mosquito populations, facilitating the widespread implementation of IIT-based management of mosquito-borne diseases. © 2024 Society of Chemical Industry.

The use of copper sulfate to control mussel (Mytella strigata) invasive events in the Penaeus vannamei shrimp farming: Doses, effects, and depuration

The global production of Pacific white shrimp Penaeus vannamei (Boone, 1931) has increased annually with advances in farming techniques. However, like any open system, it is subject to economic losses from invasive organisms, predators, and diseases. The lagoon mussel Mytella strigata, which massively invades culture ponds, reduces the primary productivity necessary for raising juvenile shrimp and is typically treated with copper sulfate pentahydrate (CuSO4.5H2O) as a molluscicide. In the search for copper sulfate doses that are effective for controlling M. strigata and cultivating P. vannamei, the mean lethal concentration for mussels (LC50; 0.57 mg CuSO4.5H2O L−1) and shrimp (LC50; 2.91 mg CuSO4.5H2O L−1) was estimated. Subsequently, the acute effect of CuSO4.5H2O on biometry and endogenous energy reserves by exposing shrimp to a dose of 1.20 mg CuSO4.5H2O L−1, and the amount of metal accumulated and detoxified from the soft tissue and exoskeleton (lethal for mussels and sublethal for shrimp) was evaluated for 12 d, followed by a detoxification period for 5 d. A significant reduction in body mass in CuSO4.5H2O-exposed shrimp was observed. Copper content was higher in the exoskeleton of CuSO4-exposed shrimp (146.3 ± 26.2 μg Cu g−1), decreasing significantly with depuration (97.9 ± 26.0 μg Cu g−1). In the soft tissue, 53.3 ± 9.8 μg Cu g−1 was accumulated, decreasing to 6.2 ± 1.3 μg Cu g−1, showing a higher percentage of detoxification (88.3 %) compared to the exoskeleton (48.5 %). Protein, carbohydrate, and lipid concentrations were not altered during copper exposure and depuration. The results suggest that sublethal exposure to CuSO4.5H2O does not affect survival, and although shrimp biomass decreased (19 % compared to control), there was no effect on their biochemical composition. Our research recommends using 1.2 mg L−1 of CuSO4.5H2O to control specific events of mussel invasion, which could be included within protocols of low environmental impact and cost.

Comparative efficacy of alternative insecticides for Rhyzopertha dominica management in Colombia: Beyond organophosphates and pyrethroids

Here, we directly compared the insecticide efficacy of diamides (chlorantraniliprole), neonicotinoids (thiamethoxam), and spinosyns (spinosad and spinetoram) with that of organophosphates (pirimiphos-methyl) and pyrethroids (deltamethrin) in Colombian populations (i.e., Ibagué; El Espinal; Granada; Pore, and Sahagún) of R. dominica. Furthermore, we established the lethal concentrations for spinetoram in our insecticide-susceptible pattern population (Ibagué) and compared this insecticide residual activity against individuals of Ibagué and El Espinal populations. The Ibagué population was most susceptible to deltamethrin and chlorantraniliprole, while Ibagué and El Espinal populations showed higher susceptibility to pirimiphos-methyl and spinetoram. Thiamethoxam exhibited similar toxicity to the Ibagué, Granada, and Sahagún populations, and the susceptibility to spinosad was similar across all populations. The spinetoram exhibited high toxicity (LC50 = 0.221 (0.174–0.287) mg a.i./Kg of grains) and residual activity against individuals from Ibagué and El Espinal populations, reinforcing its potential as alternative molecule for the management of R. dominica. Our findings expanded the insecticide options for controlling R. dominica in Colombia, contributing to avoid undesired effects of pyrethroids and organophosphates.

Azoxystrobin induced genotoxicity in Pethia conchonius, a freshwater fish of river Teesta, India

Azoxystrobin, a widely used fungicide, can contaminate water bodies through surface run-off, posing a risk to aquatic organisms. This study aimed to assess the genotoxic effects of azoxystrobin on the fish Pethia conchonius. The 96-hour lethal concentration (LC50) of azoxystrobin was determined to be 0.514 mg/L. Based on LC50, three sub-lethal concentrations (SLCs) of 0.025 mg/L, 0.0514 mg/L, and 0.103 mg/L were used to expose fish for 96 hours. The blood and gill samples were collected at 24-hour intervals for analysis. The Micronucleus (MN) and Comet assays were used to evaluate nuclear abnormalities and DNA damage, respectively. The results showed that the frequency of nuclear abnormalities and DNA damage in the exposed groups was significantly higher than the control, with increasing concentrations and duration of exposure. The highest levels of micronuclei, notched and blebbed nuclei, and DNA damage parameters were observed in the group exposed to SLC III for 96 hours. These findings indicate that azoxystrobin is highly genotoxic to fish causing severe DNA damage.

ئAntiparasitic activity of Cerastes cerastes venom on Schistosoma mansoni infected mice‏

This study investigates whether Cerastes cerastes venom (CCV) administrated at different doses (3 and 6μg/mouse) and times (a week pre-infection, the first week post-infection, and the fifth week post-infection) possesses antischistosomal activity on Schistosoma mansoni infected mice. The results showed that treatment with half lethal dose (6 μg/mouse) of CCV, at various time schedules, led to a significant decrease in the total worm burden. However, quarter lethal dose (3μg/mouse) of CCV showed a significant decrease in the total worm burden only when administered a week pre-infection. The total number of deposited eggs by females of S. mansoni was significantly decreased in the liver and the intestine of mice treated with 3μg/mouse or 6μg/mouse CCV, associated with significant alterations in the oogram pattern with significant elevation in dead eggs levels and significant decrease in the number of mature eggs. Histological examinations illustrated a significant decrease in the number and diameter of hepatic granulomas in high dose (6μg/mouse) CCV-treated groups, while it was significant only a week pre-infection in low dose (3μg/mouse) CCV-treated groups. CCV also caused several tegumental changes in treated female and male worms, including loss of the normal surface architecture, tubercular destruction, loss of tubercles' spines, oedema, erosion, membrane blebbing, and swelling. S. mansoni-infected mice groups treated with CCV (6μg/mouse) a week before infection and at fifth week post-infection had, in all individuals up to a dilution of 1:1600, higher levels of antibodies against adult worm antigen. The current investigation found that C. cerastes venom has potential antischistosomal action in a time and dose-dependent manner (more enhanced antischistosomal effects at a dose of 6 μg and in the group treated in a week before infection), in addition to its potential immunomodulatory effect against schistosomiasis infection. More studies will be required to identify the venom's active ingredients that affect the host's immunology. This information could be used in the future to develop novel antischistosomal therapies.

Nanoemulsified formulation of cell-free supernatant from Photorhabdus luminescens as a sustainable biopesticide against Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae)

The fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae), presents a significant threat to global agricultural production. While chemical pesticides have traditionally been effective in controlling such pests, the increasing demand for organic products has spurred the search for environmentally friendly alternatives. Biopesticides have emerged as a promising solution, offering efficacy while minimizing health and environmental risks associated with synthetic chemicals. In the present study, the insecticidal potential of the cell-free supernatant (CFS) from Photorhabdus luminescens, sourced from Heterorhabditis indica, was evaluated against third-instar S. frugiperda larvae through in vitro bioassays. Gas chromatography-mass spectrometry (GC-MS) analysis identified key biomolecules in the CFS, which were further studied for their interaction with S. frugiperda protein targets using in silico methods. Additionally, a nanoemulsified formulation of the CFS was developed via., ultrasonication, demonstrating stability with droplet diameters <200 nm over 90 days. Characterization through dynamic light scattering (DLS) and transmission electron microscopy (TEM) confirmed the nanoformulation's regular distribution and spherical shape, with an average diameter of 115.9 ± 5.1 nm and a zeta potential of 65 ± 1.8 mV. The CFS exhibited significant insecticidal activity, resulting in 80% mortality with a half-maximal lethal concentration (LC50) of 593.62 ppm. Furthermore, the nanoformulation displayed strong control efficacy against third-instar S. frugiperda larvae, achieving an LC50 of 578.77 ppm after 48 h of treatment. These findings highlight the potential of utilizing CFS from P. luminescens and its nanoformulation as sustainable and effective insecticide with reduced environmental impact, sustained release properties, and enhanced pest control capabilities.

Unveiling phytochemicals and antioxidant, cytotoxic, anti-thrombotic, anti-inflammatory, and antibacterial activities from the leaves of Dalbergia stipulacea (Roxb.)

The study was aimed to conduct phytochemical investigation and assess the in vitro antioxidant, cytotoxic, anti-thrombotic, anti-inflammatory and antibacterial properties of crude methanol extract of Dalbergia stipulacea leaf and its various extractives. All the fractions contain quinines, alkaloids, flavonoids, tannins, resins, glycosides, and flavonoids, while crude methanol, petroleum ether, and ethyl acetate fractions contain saponins and steroids in qualitative phytochemical analysis. In GC-MS/MS technique, a total of 44 phytoconstituents were identified and characterized, where 3-O-Methyl-D-glucose (22.80 %), 8,11,14-Docosatrienoic acid, methyl ester (19.86 %), pentadecanoic acid, methyl ester (14.17 %), 13-docosenamide (6.62 %), nonadecanoic acid, methyl ester (4.62 %), and phytol (3.04 %) were most prominent. In addition, some promising bioactive constituents, such as pantolactone, aromandendrene, D-allose, loliolide, neophytadiene, dibutyl phthalate, kolavenol, and squalene are present in the leaf of D. stipulacea plant species. Petroleum ether soluble fraction (PESF) of the plant had the highest phenolic content (27.34 mg of GAE/gm) and showed the most effective DPPH free radical scavenger with a half maximal inhibitory concentration (IC50) value of 3.87 μg/mL. The PESF also exhibited cytotoxicity with median lethal dose (LC50) value of 2.76 μg/mL compared to the standard medication vincristine sulfate (LC50 = 0.45 μg/mL) in brine shrimp lethality bioassay. Compared to streptokinase (63.34 %), aqueous soluble fraction (AQSF) displayed the highest percentage of clot lysis (38.61 %). The PESF exhibited the most significant suppression of heat-induced hemolysis (32.61 %) and hypotonic solution-induced hemolysis (33.86 %), respectively, revealing promising anti-inflammatory properties. In addition, the methanol extract and its fractions exerted promising antibacterial properties with notable zone of inhibition (6–25 mm) compared to ciprofloxacin (17–37 mm). The current evidence supports the traditional medicinal applications of the plant, particularly its ability to act as an antioxidant, cytotoxic, thrombolytic, anti-inflammatory, and antibacterial agent. However, further phytochemical isolation and in vivo screening is necessary to discover new drugs from the leaf of D. stipulacea plant species based on the current evidence.

Green-synthesized silver nanoparticles induced apoptotic cell death in CACO2 cancer cells by activating MLH1 gene expression

MLH1 (Mult homolog1) gene is the main element of Multlα heterodimer and plays a role in the repair of base-base mismatches and deletion and addition loops. When the MLH1 protein is not present, the number of errors that remain unrepaired increases, and this can lead to the formation of tumors in the body. Colorectal cancer is the third most common type of cancer in terms of incidence and the third type of cancer in terms of mortality worldwide. In this regard, the present study was conducted with the aim of investigating the effect of biological silver nanoparticles with anticancer properties and MLH1 gene expression on cancer cell samples of people with colorectal cancer. In this study, the green synthesis of silver nanoparticles was carried out by precipitation method with reduction of silver ions by leaf and flower extract of Moringa oleifera plant. Then, silver nanoparticles were confirmed using UV-visible spectroscopy, transmission and scanning electron microscopy. The cytotoxic effects of nanoparticles on cells were evaluated by MTT colorimetric method within 42 h. After RNA extraction of treated cells, cDNA synthesis and primers were designed by the Exon-Exon Junction method and the Real-time Polymerase test for MLH1 and Beta-actin genes was repeated three times. The final analysis of the results was done using Graphpad Prism and Rest 2009 software. The presence of a peak at the wavelength of 234 nm for the synthesized silver nanoparticles was confirmed by ultraviolet-visible spectroscopic analysis. The morphological study on the size and shape of the silver nanoparticles showed that the nanoparticles are spherical and have a size between 40 and 34 nanometers in diameter. The leaf extract typically produces smaller, more uniform particles than the flower extract. The Green-Synthesized Silver Nanoparticles of leaf extract were used to evaluation of induced Apoptotic Cell Death in CACO2 Cancer Cells by Activating MLH1 Gene Expression. MTT results showed that the anti-proliferative effect of nanoparticles depends on the concentration of synthesized silver nanoparticles. The treatment of MLH1 cancer cell line and normal with synthesized nanoparticles at a concentration of 0.44 micrograms per ml for 42 h showed the effects of cell toxicity. The percentage of cancer cell death under the influence of quercetin present in Moringa green bio-particles depends on the concentration and time, and this difference is statistically significant compared to the control group (P < 0.05). So that the lethal dose of the extract for 50% survival IC50 in a period of 48 h for intestinal cancer cells was equal to 21 μg/ml, and the expression ratio of the MLH1 gene in the tumor tissue to the adjacent healthy tissue has increased (P ≤ 0.05).

The DNA-based Lassa vaccine INO-4500 confers durable protective efficacy in cynomolgus macaques against lethal Lassa fever

BackgroundWe have previously developed a DNA-based vaccine, INO-4500, encoding the Lassa lineage IV glycoprotein precursor. INO-4500, when delivered with electroporation, elicited humoral and cellular responses, and conferred 100% protection in cynomolgus non-human primates. Here, we expanded the characterization of INO-4500 assessing immunogenicity and protective efficacy of lower doses and single immunization, and the durability of immune responses.MethodsThe study was divided into three arms evaluating INO-4500 vaccination: Arm 1 – Dosing regimen; Arm 2 – Single immunization; and Arm 3—Durability of immune responses and protective efficacy. Humoral and T cell responses were assessed by IgG binding ELISA, IFNγ ELISpot and flow cytometry-based T cell activation assays. NHPs were challenged with a lethal dose of Lassa lineage IV 8 weeks (Arms 1 and 2) or one year (Arm 3) after immunization. NHPs were assigned clinical scores and monitored for survival. Viremia, virus neutralization and release of soluble mediators were assessed post-challenge, as well as disease pathology following NHPs death or euthanasia.ResultsINO-4500 induces dose-dependent immune responses and protective efficacy. Animals receiving two doses of 2 mg of INO-4500 show complete short- and long-term LASV protection. NHPs receiving 1 mg of INO-4500 are protected from LASV challenge one year after vaccination but are only partially protected 8 weeks post-vaccination. LASV-specific memory T cells are present in vaccinated NHPs one year after vaccination. INO-4500 vaccination prevents NHPs from developing severe disease.ConclusionsThese studies demonstrate that INO-4500 can provide short- and long-term protection in NHPs from lethal LASV challenge.