Levels and Health Risk Assessment of Inorganic Arsenic, Methylmercury, and Heavy Metals in Edible Mushrooms Collected from Online Supermarket in China.

Chromium (Cr), total arsenic (As), inorganic arsenic (iAs), cadmium (Cd), mercury (Hg), methylmercury (MeHg), and lead (Pb) were analyzed in in Agaricus blazei, Tricholoma matsutake, Pholiota nameko, agrocybe aegirit, Boletus edulis, Auricularia auricula, and Lentinus edodes collected from online supermarket in China from 2015 to 2017. The order of mean concentrations for the five heavy metals in edible mushrooms was As > Cd > Cr > Pb > Hg. No positive correlation was found between total As and iAs, nor between total Hg and MeHg. The contents of iAs were at a low level except for A. blazei samples. The contents of MeHg were at a low level in all test mushroom samples. And Cr, Cd, and Pb pollution were common problems in the test mushroom samples. The comprehensive factor pollution index was between 0.569 (A. auricula) and 3.056 (B. edulis). The THQ values for the five heavy metals from P. nameko, A. auricula, A. aegirit, and L. edodes samples were less than 1. The hazard index (HI) values of A. blazei, T. matsutake, and B. edulis samples for adults and children were greater than 1, indicating significant health hazard to the adults and children consumers. The cancer risk (CR) values for iAs ranged from 3.82 × 10- 6 (T. matsutake) to 8.61 × 10- 5 (A. blazei), indicating no potential carcinogenic risk to the consumers. The order for carcinogenic risk of each edible mushroom species was A. blazei > L. edodes > P. nameko > A. aegirit > A. auricula > B. edulis > T. matsutake.

A noninvasive model discriminating significant histological changes in treatment-naive chronic hepatitis B patients with normal ALT.

BACKGROUND: Traditionally part of chronic hepatitis B (CHB) patients with normal alanine aminotransferase (ALT) are recommended to antiviral therapy referring to liver biopsy. However, liver biopsy is an invasive method with various potential complications. A noninvasive model was established in the study to evaluate liver histology and to identify the need of antiviral therapy. METHODS: A total of 614 liver biopsied CHB patients with ALT less than upper limit of normal from 2 centers were retrospectively analyzed. They were divided into a training cohort and a validation cohort. A noninvasive model to predict the significant liver histological changes was established and validated. RESULTS: The results of analysis showed that ALT, Age, platelet (PLT) and liver stiffness (LS) were independent risk factors for significant liver injury. The model was established based on the 4 indexes, with the area under the curve of 0.85 and 0.87 in training cohort and validation cohort. Meanwhile, 2 cut-off scores were selected. By applying the low cut-off score (- 0.207), patients without significant liver injury could be identified with high accuracy, with negative predictive value of 72.7% and 73.7% in training and validation cohorts. By applying the high cut-off score (0.537), the presence of significant liver injury could be diagnosed with high accuracy, with positive predictive value of 90.3% and 88.8% in the training and validation cohorts. By applying the model, liver biopsy would have been avoided in 87.6% (538/614) patients, with correct prediction in 87.9% (473/538). CONCLUSION: The novel noninvasive model composed of ALT, Age, PLT, LS can correctly assess liver histology in CHB patient with normal ALT, which helps to determine the need of antiviral therapy without liver biopsy.

LanCLs add glutathione to dehydroamino acids generated at phosphorylated sites in the proteome.

Enzyme-mediated damage repair or mitigation, while common for nucleic acids, is rare for proteins. Examples of protein damage are elimination of phosphorylated Ser/Thr to dehydroalanine/dehydrobutyrine (Dha/Dhb) in pathogenesis and aging. Bacterial LanC enzymes use Dha/Dhb to form carbon-sulfur linkages in antimicrobial peptides, but the functions of eukaryotic LanC-like (LanCL) counterparts are unknown. We show that LanCLs catalyze the addition of glutathione to Dha/Dhb in proteins, driving irreversible C-glutathionylation. Chemo-enzymatic methods were developed to site-selectively incorporate Dha/Dhb at phospho-regulated sites in kinases. In human MAPK-MEK1, such "elimination damage" generated aberrantly activated kinases, which were deactivated by LanCL-mediated C-glutathionylation. Surveys of endogenous proteins bearing damage from elimination (the eliminylome) also suggest it is a source of electrophilic reactivity. LanCLs thus remove these reactive electrophiles and their potentially dysregulatory effects from the proteome. As knockout of LanCL in mice can result in premature death, repair of this kind of protein damage appears important physiologically.

Interferon-based treatment is superior to nucleos(t)ide analog in reducing HBV-related hepatocellular carcinoma for chronic hepatitis B patients at high risk.

BACKGROUND: The effect of nucleos(t)ide analogs (NAs) versus interferon (IFN) on the occurrence of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) is controversial. We assessed whether antiviral strategy affected HCC development in CHB patients at different HCC risks. METHODS: 1112 CHB patients with antiviral therapy were included in this retrospective study. Patients treated with NAs only were classified into NAs group (n = 682) while those received IFN treatment with or without NAs were defined as IFN group (n = 430). Propensity score matching (PSM) was applied to minimize baseline differences. RESULTS: Totally, 31 patients developed HCC during follow-up (median 5.41 years). The cumulative HCC incidence at 10 years was significantly lower in the IFN group than NAs group (2.7% vs 8.0%, p < 0.001). Similar results were obtained in the PSM-cohort. Patients with IFN-based treatment were less likely to develop HCC than those with NAs (Hazard ratio = 0.15; 95% CI 0.04-0.66; p = 0.012). Subgroup analyses demonstrated that this superiority of IFN in reducing HCC development was obvious in patients at high- but not low-risk of HCC. CONCLUSIONS: Reduction of HCC development was more significant in CHB patients at higher HCC risk with IFN-based therapy than NAs treatment.

Enhancer of zeste homolog 2-catalysed H3K27 trimethylation plays a key role in acute-on-chronic liver failure via TNF-mediated pathway.

Acute-on-chronic liver failure is mainly due to host immunity self-destruction. The histone H3 lysine 27 (H3K27) trimethylating enzyme, enhancer of zeste homolog 2 (EZH2) mediates epigenetic silencing of gene expression and regulates immunity, also involves pathogenesis of several liver diseases. The current study was to determine the role of methyltransferase EZH2 and its catalysed H3K27 trimethylation (H3K27me3) in liver failure, and to further investigate the potential target for liver failure treatment. EZH2 and its catalysed H3K27me3 were determined in peripheral blood mononuclear cells (PBMC) from liver failure patients and Kupffer cells from experimental mice. Furthermore, GSK126 (an inhibitor for EZH2 trimethylation function) was applied in liver failure mice in vivo, and lipopolysaccharide-stimulated mononuclear cells in vitro. EZH2 and H3K27me3 were significantly upregulated in human PBMC from liver failure patients or murine Kupffer cells from the liver failure animals, respectively. GSK126 ameliorated disease severity in liver failure mice, which maybe attribute to down-regulate circulating and hepatic proinflammatory cytokines, especially TNF via reducing H3K27me3. In-depth chromatin immunoprecipitation analysis unravelled that decreased enrichment of H3K27me3 on Tnf promotor, resulting in TNF elevation in Kupffer cells from liver failure mice. Nuclear factor kappa B (NF-κB) and protein kinase B (Akt) signalling pathways were activated upon lipopolysaccharide stimulation, but attenuated by using GSK126, accompanied with decreased TNF in vitro. In conclusion, EZH2 and H3K27me3 contributed to the pathogenesis of liver failure via triggering TNF and other indispensable proinflammatory cytokines. EZH2 was to modify H3K27me3 enrichment, as well as, activation of the downstream NF-κB and Akt signalling pathways.

Bisphosphonate-Generated ATP-Analogs Inhibit Cell Signaling Pathways.

Bisphosphonates are a major class of drugs used to treat osteoporosis, Paget's disease, and cancer. They have been proposed to act by inhibiting one or more targets including protein prenylation, the epidermal growth factor receptor, or the adenine nucleotide translocase. Inhibition of the latter is due to formation in cells of analogs of ATP: the isopentenyl ester of ATP (ApppI) or an AppXp-type analog of ATP, such as AMP-clodronate (AppCCl2p). We screened both ApppI as well as AppCCl2p against a panel of 369 kinases finding potent inhibition of some tyrosine kinases by AppCCl2p, attributable to formation of a strong hydrogen bond between tyrosine and the terminal phosphonate. We then synthesized bisphosphonate preprodrugs that are converted in cells to other ATP-analogs, finding low nM kinase inhibitors that inhibited cell signaling pathways. These results help clarify our understanding of the mechanisms of action of bisphosphonates, potentially opening up new routes to the development of bone resorption, anticancer, and anti-inflammatory drug leads.

The Biomarkers of Lupus Disease Study: A Bold Approach May Mitigate Interference of Background Immunosuppressants in Clinical Trials.

OBJECTIVE: Molecular medicine raised expectations for strategically targeted biologic agents in systemic lupus erythematosus (SLE), but clinical trial results have been disappointing and difficult to interpret. Most studies add investigational agents to various, often effective, standard therapy immunosuppressants used at baseline, with unknown treatment interactions. Eliminating polypharmacy in trials of active lupus remains controversial. We undertook the Biomarkers of Lupus Disease study to test withdrawal of immunosuppressants as a novel approach to rendering SLE trials interpretable. METHODS: In 41 patients with active, non-organ-threatening SLE flare (group A), temporary steroids were given while background immunosuppressants were withdrawn. Time to loss of disease suppression (time to disease flare) and safety were evaluated; standard therapy was immediately resumed when symptoms recurred. Immunologic impacts of standard therapy were studied at baseline by multiplex assay, enzyme-linked immunosorbent assay, and messenger RNA array in group A patients plus 62 additional patients donating a single sample (group B). RESULTS: Patients with lower or higher baseline disease activity had median times to flare of 71 or 45 days, respectively; 40 of 41 patients (98%) had disease flares by 6 months. All flares were treated and resolved within 6 weeks. No serious adverse events occurred from flare or infection. Type I interferon (IFN), Th17, and B lymphocyte stimulator pathways tracked together. Baseline immunosuppressants had distinct impacts on Th17 and B lymphocyte stimulator, depending on IFN signature. CONCLUSION: Trials in active, non-organ-threatening SLE can safely withdraw background treatments if patients who have disease flares are designated nonresponders and returned to standard therapy. Immunologic effects of standard therapy vary between IFN-defined subsets. These findings provide a strategy for minimizing or optimizing treatment combinations in lupus trials and clinical care.

A Highly Efficient Single-Chain Metal-Organic Nanoparticle Catalyst for Alkyne-Azide "Click" Reactions in Water and in Cells.

We show that copper-containing metal-organic nanoparticles (MONPs) are readily synthesized via Cu(II)-mediated intramolecular cross-linking of aspartate-containing polyolefins in water. In situ reduction with sodium ascorbate yields Cu(I)-containing MONPs that serve as highly efficient supramolecular catalysts for alkyne-azide "click chemistry" reactions, yielding the desired 1,4-adducts at low parts per million catalyst levels. The nanoparticles have low toxicity and low metal loadings, making them convenient, green catalysts for alkyne-azide "click" reactions in water. The Cu-MONPs enter cells and perform efficient, biocompatible click chemistry, thus acting as intracellular nanoscale molecular synthesizers.

Hepatitis B virus dampens autophagy maturation via negative regulation of Rab7 expression.

Hepatitis B virus (HBV) infection brings a huge challenge for medical health practitioners. It has been reported that invaded HBV escapes autophagic degradation through inhibiting lysosome maturation following enhanced autophagy formation, which putatively contributes to HBV replication and infection. However, the underlying mechanism by which HBV escapes from autophagic degradation remains elusive. In this study, we monitored the autophagic process using HepG2 cells and mice without or with transient HBV DNA plasmid transfection (pHepG2) or stable HBV infection (HepG2.2.15 cells) in vitro and in vivo. The results of Western blot, transmission electron microscopy and confocal microscopy, confirmed that HBV induced autophagy, while the fusion of autophagosomes with lysosomes was arrested. Furthermore, Rab7, a small GTPase that functions as a molecular switch responsible for the autophagosome-lysosome fusion, was inhibited, suggesting a potential mechanism for HBV-induced inhibition of autophagic degradation. In conclusion, our study proposes a potential mechanism for how HBV escapes autophagic degradation, which might be a novel therapeutic target for controlling HBV infection.

Antiinfectives targeting enzymes and the proton motive force.

There is a growing need for new antibiotics. Compounds that target the proton motive force (PMF), uncouplers, represent one possible class of compounds that might be developed because they are already used to treat parasitic infections, and there is interest in their use for the treatment of other diseases, such as diabetes. Here, we tested a series of compounds, most with known antiinfective activity, for uncoupler activity. Many cationic amphiphiles tested positive, and some targeted isoprenoid biosynthesis or affected lipid bilayer structure. As an example, we found that clomiphene, a recently discovered undecaprenyl diphosphate synthase inhibitor active against Staphylococcus aureus, is an uncoupler. Using in silico screening, we then found that the anti-glioblastoma multiforme drug lead vacquinol is an inhibitor of Mycobacterium tuberculosis tuberculosinyl adenosine synthase, as well as being an uncoupler. Because vacquinol is also an inhibitor of M. tuberculosis cell growth, we used similarity searches based on the vacquinol structure, finding analogs with potent (∼0.5-2 µg/mL) activity against M. tuberculosis and S. aureus. Our results give a logical explanation of the observation that most new tuberculosis drug leads discovered by phenotypic screens and genome sequencing are highly lipophilic (logP ∼5.7) bases with membrane targets because such species are expected to partition into hydrophobic membranes, inhibiting membrane proteins, in addition to collapsing the PMF. This multiple targeting is expected to be of importance in overcoming the development of drug resistance because targeting membrane physical properties is expected to be less susceptible to the development of resistance.

Mice lacking Tbk1 activity exhibit immune cell infiltrates in multiple tissues and increased susceptibility to LPS-induced lethality.

TBK1 is critical for immunity against microbial pathogens that activate TLR4- and TLR3-dependent signaling pathways. To address the role of TBK1 in inflammation, mice were generated that harbor two copies of a mutant Tbk1 allele. This Tbk1(Δ) allele encodes a truncated Tbk1(Δ) protein that is catalytically inactive and expressed at very low levels. Upon LPS stimulation, macrophages from Tbk1(Δ/Δ) mice produce normal levels of proinflammatory cytokines (e.g., TNF-α), but IFN-ß and RANTES expression and IRF3 DNA-binding activity are ablated. Three-month-old Tbk1(Δ/Δ) mice exhibit mononuclear and granulomatous cell infiltrates in multiple organs and inflammatory cell infiltrates in their skin, and they harbor a 2-fold greater amount of circulating monocytes than their Tbk1(+/+) and Tbk1(+/Δ) littermates. Skin from 2-week-old Tbk1(Δ/Δ) mice is characterized by reactive changes, including hyperkeratosis, hyperplasia, necrosis, inflammatory cell infiltrates, and edema. In response to LPS challenge, 3-month-old Tbk1(Δ/Δ) mice die more quickly and in greater numbers than their Tbk1(+/+) and Tbk1(+/Δ) counterparts. This lethality is accompanied by an overproduction of several proinflammatory cytokines in the serum of Tbk1(Δ/Δ) mice, including TNF-α, GM-CSF, IL-6, and KC. This overproduction of serum cytokines in Tbk1(Δ/Δ) mice following LPS challenge and their increased susceptibility to LPS-induced lethality may result from the reactions of their larger circulating monocyte compartment and their greater numbers of extravasated immune cells.

Simultaneous telemetric monitoring of tail-skin and core body temperature in a rat model of thermoregulatory dysfunction.

Temperature dysfunction, clinically described as hot flashes/flushes and night sweats, commonly occur in women transitioning through menopause. Research in this field has yet to fully elucidate the biological underpinnings explaining this dysfunction. The need to develop animal models that can be used to study hormone-dependent temperature regulation is essential to advancing this scientific area. Development of telemetric transmitters for monitoring tail-skin (TST) and core body (CBT) temperatures for animal research has increased the accuracy of data by reducing extraneous factors associated with previous methods. However, until recently, TST and CBT could not be simultaneously measured telemetrically within the same animal. In this report, new dual temperature monitoring transmitters were validated by simultaneously evaluating them with the single measurement transmitters using the ovariectomized (OVX) rat thermoregulatory dysfunction model. A major advantage of measuring TST and CBT in the same animal is the ability to relate temporal changes on these two temperature parameters. Comparative experimentation was performed by single administration of clonidine (alpha(2) adrenergic agonist), MDL-100907 (5-HT(2a) antagonist), or a 7-day treatment of 17alpha-ethinyl estradiol (EE). Clonidine caused decreases in TST and CBT, MDL-100907 caused increases in TST while decreasing CBT, and EE caused decreases in TST with minor CBT decreases only at the higher dose. Data from either probe type showed similar results on temperature parameters regardless of transmitter used. These findings support the use of the new dual temperature transmitters and should enhance the quality and interpretation of data being generated in thermoregulation studies.