Copper nanoparticles lead to reproductive dysfunction by affecting key enzymes of ovarian hormone synthesis and metabolism in female rats.

Studies on the general toxicity of copper nanoparticles (Cu NPs) have been conducted extensively, but their effects on reproductive toxicity remain unclear. In this study, we evaluated the toxic effect of Cu NPs on pregnant rats and their litter. The comparative in vivo toxicity of Cu ions, Cu NPs, and Cu microparticles (MPs) was studied in a 17-day repeated oral-dose experiment at the doses of 60, 120, and 180 mg/kg/day in pregnant rats. The pregnancy rate, mean live litter size, and number of dams decreased when exposed to Cu NPs. Moreover, Cu NPs caused a dose-dependent increase in ovarian Cu levels. The metabolomics results showed that Cu NPs caused reproductive dysfunction by altering sex hormones. In addition, in vivo and in vitro experiments showed that the ovarian cytochrome P450 enzymes (CYP450), responsible for hormone production, were significantly upregulated, whereas the enzymes responsible for hormone metabolism were significantly inhibited, resulting in a metabolic imbalance in some ovarian hormones. Furthermore, the results revealed that the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways significantly participated in the regulation of ovarian CYP enzyme expression. Overall, the results of the in vivo and in vitro toxicity experiments with Cu ions, Cu NPs, and Cu MPs suggested that toxicity from nanoscale Cu particles poses a more serious reproductive threat than microscale Cu as Cu NPs could directly damage the ovary and affect the metabolism of ovarian hormones.

Aseismic slip and recent ruptures of persistent asperities along the Alaska-Aleutian subduction zone.

The frictional properties and slip behaviors of subduction thrusts play a key role in seismic and tsunami hazard assessment, especially in weakly coupled "seismic gaps". Here, we rely on GPS observations in the Shumagin Gap of the Aleutian subduction zone to derive the slip distribution of the 2020 Mw 7.8 Simeonof Island, Alaska earthquake and of the subsequent afterslip during the first 87-day period. Our modeling results show that the mainshock ruptured at depths of ∼30-40 km beneath Simeonof Island. Kinematic and stress-driven models indicate that the afterslip occurred both updip and downdip of the mainshock rupture. Physically plausible locking models derived from interseismic GPS velocities suggest that the 2020 Simeonof and 2021 Mw 8.2 Chignik earthquakes ruptured persistent asperities on the subduction thrust. We infer that there are several additional persistent asperities at depths of 20-50 km west ∼157°W. However, it is still uncertain whether there are additional locked asperities at shallow depths because of the current lack of geodetic observations close to the trench.

Cytokine storms and pyroptosis are primarily responsible for the rapid death of mice infected with pseudorabies virus.

Pseudorabies virus (PRV), the causative agent of Aujeszky's disease, is one of the most harmful pathogens to the pig industry. PRV can infect and kill a variety of mammals. Nevertheless, the underlying pathogenesis related to PRV is still unclear. This study aims to investigate the pathogenesis induced by PRV in a mouse model. The mice infected with the PRV-HLJ strain developed severe clinical manifestations at 36 h post-infection (hpi), and mortality occurred within 48-72 hpi. Hematoxylin-eosin staining and qRT-PCR methods were used to detect the pathological damage and expression of cytokines related to an immune reaction in brain tissue, respectively. The cytokine storms caused by IFN-α, IFN-ß, TNF-α, IL-1ß, IL-6 and IL-18 were related to the histopathological changes induced by PRV. This pattern of cytokine secretion depicts an image of typical cytokine storms, characterized by dysregulated secretion of pro-inflammatory cytokines and imbalanced pro-inflammatory and anti-inflammatory responses. In addition, the pyroptosis pathway was also activated by PRV by elevating the expression levels of nod-like receptor protein 3, Caspase-1, Gasdermin-D and interleukin-1ß/18. These findings provide a way for further understanding the molecular basis in PRV pathogenesis.

Purification and characterization of plantaricin 163, a novel bacteriocin produced by Lactobacillus plantarum 163 isolated from traditional Chinese fermented vegetables.

Presumptive lactic acid bacteria (LAB) strains isolated from traditional Chinese fermented vegetables were screened for bacteriocin production. A novel bacteriocin-producing strain, Lactobacillus plantarum 163, was identified on the basis of its physiobiochemical characteristics and characterized by 16S rDNA sequencing. The novel bacteriocin, plantaricin 163, produced by Lb. plantarum 163 was purified by salt precipitation, gel filtration, and reverse-phase high-performance liquid chromatography (RP-HPLC). Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) analysis of plantaricin 163 revealed the molecular weight to be 3553.2 Da. The complete amino acid sequence showed VFHAYSARGNYYGNCPANWPSCRNNYKSAGGK, and no similarity to known bacteriocins was found. Plantaricin 163 was highly thermostable (20 min, 121 °C), active in the presence of acidic pH (3-5), sensitive to protease, and exhibited broad-spectrum antimicrobial activity against LAB and other tested Gram-positive and Gram-negative bacteria. The results suggest that plantaricin 163 may be employed as a biopreservative in the food industry.

The involvement of PDGF/VEGF related factor in regulation of immune and neuroendocrine in Chinese mitten crab Eriocheir sinensis.

Members of the platelet-derived growth factor/vascular endothelial growth factor (PDGF/VEGF) family have been implicated in cell proliferation, cell differentiation, and cell migration, vascular development, angiogenesis and neural development. In the present study, a novel PDGF/VEGF related factor gene was cloned and identified in Chinese mitten crab Eriocheir sinensis (designated as EsPVF1). The full-length cDNA of EsPVF1 was of 1173 bp, consisting a 5' untranslated region (UTR) of 54 bp, a 3' UTR of 1131 bp with a poly (A) tail, and an open reading frame (ORF) of 588 bp encoding 196 amino acid residues. A signal peptide of 20 amino acid residues, a PDGF/VEGF homology growth factor domain of 81 amino acids, and a typical cysteine knot motif (CXCXC) were identified in the deduced amino acid sequence of EsPVF1. By fluorescent quantitative real-time PCR, the EsPVF1 mRNA was detected ubiquitously in the select tissues of hemocytes, gonad, heart, muscle, hepatopancreas and gill, with the high abundance in hemocytes and gonad. The mRNA expression level of EsPVF1 was up-regulated and reached the highest at 24 h after Vibrio anguillarum challenge, while it was induced at 3 h, 6 h, 12 h, 24 h and 48 h compared with the untreated group after Pichia pastoris GS115 challenge. Tissue injury also induced the mRNA expression of EsPVF1 in hemocytes of crabs, and the expression level increased obviously at 8 h. The cDNA fragment encoding mature peptide of EsPVF1 was recombined and expressed in Escherichia coli BL21 (DE3) pLysS. Biogenic amine in hemolymph pre-incubated with recombinant protein of EsPVF1 (rEsPVF1) was detected by fluorimetric method. Norepinephrine and dopamine in hemolymph incubated with rEsPVF1 were higher than that in the blank group. Therefore, EsPVF1 could significantly provoke the release of norepinephrine and dopamine. The results collectively indicated that EsPVF1 was involved in regulation of the immune response and neuroendocrine system in crabs.

Comparative performance of electrochemiluminescence immunoassay and EIA for HIV screening in a multiethnic region of China.

BACKGROUND: The recent approval of 4th generation HIV tests has forced many laboratories to decide whether to shift from 3rd to these tests. There are limited published studies on the comparative evaluation of these two different assays. We compare the performance of fourth-generation electrochemiluminescence immunoassay (ChIA) and third-generation enzyme linked immunosorbent assay (EIA) for human immunodeficiency virus (HIV) screening and gauge whether the shift from EIA to ChIA could be better in a multiethnic region of China. METHODOLOGY/PRINCIPAL FINDINGS: We identified a large number of routine specimens (345,492) using two different assays from Jan 2008 to Aug 2011 in a teaching hospital with high sample throughput. Of the 344,596 specimens with interpretable HIV test results, 526(0.23%) of 228,761 using EIA and 303(0.26%) of 115,835 using ChIA were HIV-1 positive. The false-positive rate of EIA was lower than that of ChIA [0.03% vs. 0.08%, odds ratio 0.33 (95% confidence interval 0.24, 0.45)]. The positive predictive value (PPV) of EIA (89.6%) was significantly higher than that of ChIA (76.1%) (<0.001), reflecting the difference between the two assays. The clinical sensitivities of two assays in this study were 99.64% for EIA and 99.88% for ChIA. CONCLUSION: Caution is needed before shifting from 3rd to 4th generation HIV tests. Since none of these tests are perfect, different geographic and ethnic area probably require different considerations with regard to HIV testing methods, taking into account the local conditions.

[Study on separation and purification of total alkaloids from Macleaya cordata].

A method for separation and purification of total alkaloids from Macleaya cordata with macroporous resin was studied, with the content and recovery rate of total alkaloids as indexes. The results were as follows: The static adsorption capacity of AB-8 type resin was 104. 65 mg/g, the static elution ratio were 95.9% , the dynamic adsorption capacity of AB-8 type resin was 96.5 mg/g, the recovery rate was more than 91.24% and the purity was more than 90%. AB-8 type resin was the best for separating and purificating Macleaya cordata in total alkaloids. The optimum conditions is: the eluant is 90% alcohol and 2-3 times as the volume of the resin, the volume of the resin is 10.4 times of total alkaloids in sample, concentration of total alkaloids of sample is 21.57 mg/ml and current velocity of 2-3 ml/min, pH value of sample is 7-8.

[Study on extraction technics and variety trends of the flavonoids in Sarcandrae glabra].

OBJECTIVE: To study on extraction technics and variety trends of the flavonoids in Sarcandrae glabra. METHOD: By using S. glabra in Guizhou as materials and the experiment of L9 (3(4)) by ethanol as extracting way, The variety trends of the flavonoids from S. glabra are studied under the optimum extracting conditions during different raw stored times, different gathering season, different S. glabra position. RESULT: The flavonoid's contains was more low when the raw material was stored more long and descended average 24.74% annually. The flavonoid's contains had the tallest in 10-12 month by gathering indifferent season. The flavonoids contains were the tallest in the leaf of S. glabra in Guizhou than in the root and stem, and the contains were the lowest in stem. CONCLUSION: The optimum conditions of extracting flavonoids from S. glabra are obtained when the condition is 60% of density of ethanol at 10 times of volume, 80 degrees C of extracting temperature, 3 h of extracting hours, 3 times of extracting number of times in 10-12 month, in the leaf, the raw material was stored more shortest, the flavonoid's contains had the tallest.

[Separation and purification of flavonoids from chrysanthemum indicum with macroporous resin].

OBJECTIVE: A method for separation and purification of flavonoids from C. indicum with macroporous resin was studied. METHOD: By using C. indicum in Guizhou as the materials and with the content and recovery rate of flavonoids as indexes, the static and dynamic adsorption tests were employed to investigated effects and affective factors of separation and purification of flavonoids from C. indicum with macroporous resin. RESULT: Results show that the static adsorption capacity of AB-8 type resin was 114.65 mg x g(-1), the static elution ratio were 94.9%, the dynamic adsorption capacity of AB-8 type resin was 94.5 mg x g(-1), the recovery rate was more than 92.6% and the purity of flavonoids was more than 90%. AB-8 type resin is the best for separating and purificating C. indicum in flavonoids. CONCLUSION: The optimum conditions is AB-8 type macroporous resin, 70% alcohol as the eluant and 2 to approximately 3 times volume of the resin as the eluant volume, the ratio of flavonoids to the volume of the resin as 1:10.6, concentration of flavonoids of sample as 19.8 mg x mL(-1) and current velocity as 2 to approximately 3 mL x min(-1), pH value of sample as 4 to approximately 5. [Key words]' macroporous resin; Chrysanthemum indicum; flavonoids; separation; purification