Assessment of Lambda-Cyhalothrin and Spinetoram Toxicity and Their Effects on the Activities of Antioxidant Enzymes and Acetylcholinesterase in Honey Bee (Apis mellifera) Larvae.

Honeybees play a crucial role as agricultural pollinators and are frequently exposed to various pollutants, including pesticides. In this study, we aimed to evaluate the toxicity of lambda-cyhalothrin (LCY) and spinetoram (SPI) in honey bee larvae reared in vitro through single (acute) and repeated (chronic) exposure. The acute LD50 values for LCY and SPI were 0.058 (0.051-0.066) and 0.026 (0.01-0.045) µg a.i./larva, respectively. In chronic exposure, the LD50 values of LCY and SPI were 0.040 (0.033-0.046) and 0.017 (0.014-0.019) µg a.i./larva, respectively. The chronic no-observed-effect dose of LCY and SPI was 0.0125 µg a.i./larva. Adult deformation rates exceeded 30% in all LCY treatment groups, showing statistically significant differences compared to the solvent control group (SCG). Similarly, SPI-treated bees exhibited significantly more deformities than SCG. Furthermore, we examined the activities of several enzymes, namely, acetylcholinesterase (AChE), glutathione-S-transferase (GST), catalase (CAT), and superoxide dismutase (SOD), in larvae, pupae, and newly emerged bees after chronic exposure at the larval stage (honey bee larval chronic LD50, LD50/10 (1/10th of LD50), and LD50/20 (1/20th of LD50)). LCY and SPI induced significant changes in detoxification (GST), antioxidative (SOD and CAT), and signaling enzymes (AChE) during the developmental stages (larvae, pupae, and adults) of honey bees at sublethal and residue levels. Our results indicate that LCY and SPI may affect the development of honey bees and alter the activity of enzymes associated with oxidative stress, detoxification, and neurotransmission. These results highlight the potential risks that LCY and SPI may pose to the health and normal development of honey bees.

Transcriptome Profiling of Etridiazole-Exposed Zebrafish (Danio rerio) Embryos Reveals Pathways Associated with Cardiac and Ocular Toxicities.

Etridiazole (EDZ) is a thiadiazole-containing fungicide commonly used to control Pythium and Phytophthora spp. Although previous studies have shown that EDZ is teratogenic, the exact molecular mechanisms underlying its toxicity remain unknown. In this study, a zebrafish (Danio rerio; ZF) model was used to explore the molecular pathways associated with EDZ toxicity. The whole transcriptome of ZF embryos exposed to 96 h of EDZ was analyzed, along with developmental abnormalities. EDZ-induced malformations were primarily related to the eyes, heart, and growth of the ZF. Compared to untreated ZF, etridiazole-treated ZF had 2882 differentially expressed genes (DEGs), consisting of 1651 downregulated genes and 1231 upregulated genes. Gene ontology enrichment analysis showed that DEGs were involved in biological processes, such as sensory perception, visual perception, sensory organ development, and visual system development, and showed transmembrane transporter and peptidase regulator activities. Metabolism, phototransduction, aminoacyl-tRNA biosynthesis, MAPK signaling pathway, calcium signaling pathway, and vascular smooth muscle contraction were among the most enriched KEGG pathways. The qPCR analyses of the eight random genes were in good agreement with the transcriptome data. These results suggest several putative mechanisms underlying EDZ-induced developmental deformities in ZF.

In vitro assessments of bone microcomputed tomography in an aged male rat model supplemented with Panax ginseng.

Recent research has confirmed that Panax ginseng (P. ginseng) has effect on cultured osteoblast of the mouse. In this study we aim to validate the usefulness of tibia quantification by correlating micro-computed tomographic (microCT) images with histology analysis in the aged male rats. A total of thirty - old male WISTAR rats were used and divided into ten 8 weeks rats and ten 112 weeks aged rats with vehicle and ten 112 weeks aged rats with P. ginseng (300 mg/kg/day). Daily oral administration of P. ginseng lasted for 8 weeks. Bone histomorphometric parameters and the trabecular bone microarchitectural properties of tibia were determined by microCT scan. MicroCT analysis showed significantly lower bone mineral density (BMD) and trabecular bone number in the aged group. Ginseng prevented total BMD decrease in the tibia induced by natural aging, which was accompanied by a significant decrease in skeletal remodeling. Furthermore, the aged group with ginseng was found to have a significantly higher osteoblast. In the blood biochemistry results, serum phosphorus, calcium, osteocalcin, T3, and T4 remained unchanged. The present study indicated that P. ginseng might be a potential alternative medicine for the prevention and treatment of natural aging-induced osteoporosis in human.

Control Efficacy of Streptomyces sp. A501 against Ginseng Damping-off and Its Antifungal Substance.

Ginseng damping-off, caused by the fungal pathogens Rhizoctonia solani and Pythium sp., is a critical disease in ginseng seedling. In a continuing effort to find microorganisms with the potential of acting as a biocontrol agent against Rhizoctonia damping-off, we found that a Streptomyces sp. A501 showed significant antifungal activity against Rhizoctonia solani. In field experiment to test the efficacy of Streptomyces sp. A501 in controlling ginseng damping-off, the incidence of damping-off disease was meaningfully reduced when ginseng seeds were soaked in the culture broth of Streptomyces sp. A501 before sowing. To perform characterization of the antifungal compound, we isolated it from the culture broth of strain A501 through Diaion HP-20 and silica gel column chromatographies and preparative high-performance liquid chromatography. The structure of the antifungal compound was assigned as fungichromin by spectroscopic methods, mainly nuclear magnetic resonance and electrospray ionization-mass analysis.

Endosulfan-induced biomarkers in Japanese rice fish (Oryzias latipes) analyzed by SELDI-TOF-MS.

The objective of this study was to find and validate estrogen-related biomarkers from plasma proteins in Oryzias latipes after exposure to an estrogen disrupting compound, α-endosulfan. The acute toxicity of α-endosulfan on O. latipes after 96 h of exposure was 13.72, 16.18, and 22.18 µg L(-1) for the LC10, LC20, and LC50 values, respectively. To confirm estrogenic disturbance by α-endosulfan, the expression level of vitellogenin in the liver of male fishes was measured at the LC10 value, and it was found to be significantly different from the reference group, confirming the estrogenic effect of endosulfan in this concentration range. Proteinchip® array techniques using a weak cation exchange (CM10) and a strong anion exchange proteinchip (Q10) in conjunction with surface-enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF-MS) were used to determine plasma proteins of O. latipes differently expressed in response to endosulfan exposure at LC10 and LC20 concentrations. Analysis of protein profiling of the male fish exposed to α-endosulfan detected 48 significantly different protein peaks and the proteins at m/z 2819, 8462, 8860, and 9462 were significantly different (p<0.05). The protein peaks at m/z 2819, 8860, and 9462 were up-regulated and the peak at m/z 8462 was down-regulated. Therefore, these four differentially expressed proteins could be used as biomarkers to rapidly determine a possible risk of endosulfan on aquatic ecosystems, although these are not necessarily produced as a result of endocrine disruption.

Comparison of sample preparation methods for the recovery of foodborne pathogens from fresh produce.

Sample preparation methods (pummeling, pulsifying, sonication, and shaking by hand) were compared for achieving maximum recovery of foodborne pathogens from iceberg lettuce, perilla leaves, cucumber, green pepper, and cherry tomato. Antimicrobial and dehydration effects also were examined to investigate causes of poor recovery of pathogens. Each produce type was inoculated with Escherichia coli O157:H7, Salmonella Typhimurium, Listeria monocytogenes, Staphylococcus aureus, and Bacillus cereus at 6.0 log CFU/cm(2), and samples were prepared using the four methods. Bacterial populations recovered from the five types of produce were significantly different (P < 0.05) according to sample preparation methods and produce type. The bacterial populations recovered from pummeled and pulsified samples were higher (P < 0.05) than those recovered from sonicated and hand-shaken samples, except for cherry tomato. The number of bacteria recovered from produce was reduced (P < 0.05) from that of the inoculum by 0.16 to 2.69 log CFU/cm(2). Although extracts of iceberg lettuce, perilla leaves, cucumber, and green pepper had no antimicrobial activity, the populations of E. coli O157:H7, Salmonella Typhimurium, B. cereus, and L. monocytogenes in cherry tomato extract were slightly reduced after these treatments (P < 0.05). The pathogen populations on perilla leaves and cherry tomatoes decreased by >2 log CFU/cm(2) after exposure to 40% relative humidity for 1 h. No reduction was observed when the five pathogens were exposed to 90% relative humidity. These data suggest that pummeling and pulsifying are optimal sample preparation methods for detection of microorganisms. Acidic produce such as cherry tomato should be treated with a method that does not cause sample breakdown so that acid stress on the bacteria can be minimized. Dehydration stress also affects recovery of pathogens from produce.