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Aflatoxin B1 (AFB1) is the major mycotoxin that contaminates aquafeeds and regarded as a causative agent in illnesses and the mortality of aquacultural species. However, the effects of AFB1 on developing fish and associated toxic mechanism are still unknown. This study examines the behavioral changes, neuronal morphology and gene expression in zebrafish embryos and larvae upon exposure to aflatoxin solutions. Treatment of 6 h post fertilization (hpf) embryos with AFB1 at 15–75 ng/mL significantly changed the swimming patterns of seven days post-fertilization (dpf) zebrafish larvae. Larvae in the 15 ng/mL group demonstrated a hypolocomotor activity in free swimming, but hyperlocomotion was observed in the larvae exposed to 30–75 ng/mL AFB1. AFB1 at 75 ng/mL also significantly reduced the startle response of 7 dpf larvae after tapping stimulus. Exposure to AFB1 resulted in an aberrant morphology of trigeminal ganglion and hindbrain neurons in transgenic embryos (HuC:eGFP); this finding was supported by acetylated alpha-tubulin staining in wild-type fish. Additionally, AFB1 altered the levels of neurotoxic markers, including gfap and huC. The transcriptomic profile of AFB1-treated embryos revealed several differentially expressed genes that are related to neuroactivity and neurogenesis. PCR analysis verified that AFB1 significantly down-regulated the expression of ngfa and atp1b1b genes and increased that of prtga gene. The results herein indicate the toxicological impacts of AFB1 on the behaviors and neurodevelopment of fish in the early embryonic stage. Disruption of neural formation and synapse dysfunction may be responsible for the behavioral alteration.

In this study, the effects of different fruit parts and extraction conditions on the antioxidant properties of jujube (Ziziphus jujuba Mill.) fruit were investigated. Five in vitro antioxidant models and statistical analyses were performed. The results revealed that jujube peel with pulp (peel pulp) exhibited better antioxidant capacity than did seeds. Overall, jujube peel pulp extracted using 50% ethanol at 60 &deg, C exhibited the best antioxidant capacity in terms of 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (0.3 &plusmn, 0 mg/mL), 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity (0.5 &plusmn, 0 mg/mL), total phenolic content (38.3 &plusmn, 0.4 mg gallic acid equivalent per gram dry weight), total flavonoid content (43.8 &plusmn, 0.2 mg quercetin equivalent per gram dry weight), and reducing power (41.9 &plusmn, 2.2 mg ascorbic acid equivalent per gram dry weight). The results indicated that jujube peel pulp is a more potential natural antioxidant than seeds.

Intercellular communication is quintessential for multicellularity and often mediated by secreted peptide ligands. In Metazoa, proprotein convertases are a major class of endoproteases partaking in the proteolytic processing of these ligands, which is in turn required for their signaling activities. In vertebrates, the best-studied convertase substrates are neuropeptides, peptide hormones, and members of the TGFβ/BMP-family. Each ligand is processed by a particular subset of convertases. Therefore, the diversification of convertases may have contributed to the growing complexity of cellular communication in metazoan evolution. However, proprotein convertases have not been systematically explored in Metazoa. Here, we sampled the representative metazoan genomes and established that six Kexin-like proprotein convertases were present in the last common ancestor of protostomes and deuterostomes. Among these, we identified a novel PCSKX orthologous group (OG) that was lost in vertebrates. Spiralian protosomes have, in general, maintained all six OGs. Therefore, we characterized the functional divergence of the Kexin-like OGs in the leechHelobdella, an experimentally tractable spiralian. Gene expression patterns suggested that PCSK1 and PCSK2 are specialized for the processing of neuropeptides and peptide hormones in bilaterians and that the newly identified PCSKX is probably functionally similar to furin and PCSK7. Finally, we showed that, distinct from the BMP morphogen in vertebrate embryos, the convertase-mediated proteolytic cleavage is not required for the short-range BMP signaling in the dorsoventral patterning of leech ectoderm. Together, our data revealed the complexity of the Kexin-like proprotein convertase gene family and their roles in generating diverse patterns of cellular communication in Metazoa.

Aflatoxin B

Among 30 urinary isolates of Staphylococcus saprophyticus identified by sequencing methods, the rate of accurate identification was 100% for Bruker Biotyper matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS), 86.7% for the Phoenix PID and Vitek 2 GP systems, 93.3% for the MicroScan GP33 system, and 46.7% for the BBL CHROMagar Orientation system.

Background/PurposeLaboratory analytical turnaround time represents laboratory effectiveness. Our study aimed to evaluate laboratory analytical turnaround time to optimize workflow and shorten analytical turnaround time.MethodsWe used the laboratory information system in a 2000-bed teaching hospital to compute and analyze the 90th percentile turnaround time of the Stat Laboratory from 2001 to 2003.ResultsThe overall 90th percentile turnaround time in the Stat Laboratory was 40–49 minutes and positively correlated with test volume. The daily test volume in the Stat Laboratory has grown significantly in the latter 2 half-years of the study as compared with the previous 2 half-years (p < 0.05 and p < 0.001, respectively). The daily longest turnaround time occurred in the early morning, and troponin-I testing contributed to the majority of incidences of prolongation of analytical turnaround time. We prioritized the performance of troponin-I testing, which resulted in a reduction of the analytical turnaround time by about 18 minutes (from 66 to 48 minutes) and no increment of overall turnaround time (42 to 44 minutes) despite continuously increasing test volume.ConclusionThese findings demonstrated that a dedicated means of process control was able to significantly improve laboratory efficiency.