A new species of the Asian leaf litter toad genus Leptobrachella (Amphibia, Anura, Megophryidae) from southwest China

A new species of the Asian leaf litter toad genus Leptobrachella from Guizhou Province, China is described based on molecular phylogenetic analyses, morphological comparisons, and bioacoustics data. Phylogenetic analyses based on the mitochondrial 16S rRNA gene sequences supported the new species as an independent clade nested into the Leptobrachella clade and sister to L.bijie. The new species could be distinguished from its congeners by a combination of the following characters: small body size (SVL 30.8–33.4 mm in seven adult males, and 34.2 mm in one adult female); dorsal skin shagreened, some of the granules forming longitudinal short skin ridges; tympanum distinctly discernible, slightly concave; internasal distance longer than interorbital distance; supra-axillary, femoral, pectoral and ventrolateral glands distinctly visible; absence of webbing and lateral fringes on fingers; toes with rudimentary webbing and shallow lateral fringes, relative finger lengths II < IV < I < III; heels overlapped when thighs are positioned at right angles to the body; and tibia-tarsal articulation reaches the tympanum.

A new species of the horned toad Megophrys Kuhl & Van Hasselt, 1822 (Anura, Megophryidae) from southwest China

A new species of the genus Megophrys is described from Guizhou Province, China. Molecular phylogenetic analyses based on mitochondrial DNA and nuclear DNA sequences all strongly supported the new species as an independent clade sister to M.minor and M.jiangi. The new species could be distinguished from its congeners by a combination of the following characters: body size moderate (SVL 43.4–44.1 mm in males, and 44.8–49.8 mm in females; vomerine teeth absent; tongue not notched behind; a small horn-like tubercle at the edge of each upper eyelid; tympanum distinctly visible, rounded; two metacarpal tubercles on palm; relative finger lengths II < I < V < III; toes without webbing; heels overlapping when thighs are positioned at right angles to the body; tibiotarsal articulation reaching the level between tympanum and eye when leg stretched forward; in breeding males, an internal single subgular vocal sac in male, and the nuptial pads with black spines on dorsal surface of bases of the first two fingers.

Comprehensive analysis reveals distinct mutational signature and its mechanistic insights of alcohol consumption in human cancers

Alcohol consumption is a critical risk factor for multiple types of cancer. A genome can be attacked and acquire numerous somatic mutations in the environment of alcohol exposure. Mutational signature has the capacity illustrating the complex somatic mutation patterns in cancer genome. Recent studies have discovered distinct mutational signatures associating with alcohol consumption in liver and esophageal cancers. However, their prevalence among diverse cancers, impact of genetic background and origin of alcohol-induced mutational signatures remain unclear. By a comprehensive bioinformatics analysis on somatic mutations from patients of four cancer types with drinking information, we identified nine mutational signatures (signatures B-J), among which signature J (similar to COSMIC signature 16) was distinctive to alcohol drinking. Signature J was associated with HNSC, ESCA and LIHC but not PAAD. Interestingly, patients with mutated allele rs1229984 in ADH1B had lower level of signature J while mutated allele rs671 in ALDH2 exhibited higher signature J abundance, suggesting acetaldehyde is one cause of signature J. Intriguingly, somatic mutations of three potential cancer driver genes (TP53, CUL3 and NSD1) were found the critical contributors for increased mutational load of signature J in alcohol consumption patients. Furthermore, signature J was enriched with early accumulated clonal mutations compared to mutations derived from late tumor growth. This study systematically characterized alcohol-related mutational signature and indicated mechanistic insights into the prevalence, origin and gene-environment interaction regarding the risk oncogenic mutations associated with alcohol intake.

Alternative polyadenylation dependent function of splicing factor SRSF3 contributes to cellular senescence

Down-regulated splicing factor SRSF3 is known to promote cellular senescence, an important biological process in preventing cancer and contributing to individual aging, via its alternative splicing dependent function in human cells. Here we discovered alternative polyadenylation (APA) dependent function of SRSF3 as a novel mechanism explaining SRSF3 downregulation induced cellular senescence. Knockdown of SRSF3 resulted in preference usage of proximal poly(A) sites and thus global shortening of 3′ untranslated regions (3′ UTRs) of mRNAs. SRSF3-depletion also induced senescence-related phenotypes in both human and mouse cells. These 3′ UTR shortened genes were enriched in senescence-associated pathways. Shortened 3′ UTRs tended to produce more proteins than the longer ones. Simulating the effects of 3′ UTR shortening by overexpression of three candidate genes (PTEN, PIAS1 and DNMT3A) all led to senescence-associated phenotypes. Mechanistically, SRSF3 has higher binding density near proximal poly(A) site than distal one in 3′ UTR shortened genes. Further, upregulation of PTEN by either ectopic overexpression or SRSF3-knockdown induction both led to reduced phosphorylation of AKT and ultimately senescence-associated phenotypes. We revealed for the first time that reduced SRSF3 expression could promote cellular senescence through its APA-dependent function, largely extending our mechanistic understanding in splicing factor regulated cellular senescence.

In-Vivo Toxicity Studies and In-Vitro Inactivation of SARS-CoV-2 by Povidone-iodine In-situ Gel Forming Formulations

To curb the spread of SARS-CoV-2, the etiologic agent of the COVID-19 pandemic, we characterize the virucidal activity of long-acting Povidone Iodine (PVP-I) compositions developed using an in-situ gel forming technology. The PVP-I gel forming nasal spray (IVIEW-1503) and PVP-I gel forming ophthalmic eye drop (IVIEW-1201) rapidly inactivated SARS-CoV-2, inhibiting the viral infection of VERO76 cells. No toxicity was observed for the PVP-I formulations. Significant inactivation was noted with preincubation of the virus with these PVP-I formulations at the lowest concentrations tested. It has been demonstrated that both PVP-I formulations can inactivate SARS-CoV-2 virus efficiently in both a dose-dependent and a time-dependent manner. These results suggest IVIEW-1503 and IVIEW-1201 could be potential agents to reduce or prevent the transmission of the virus through the nasal cavity and the eye, respectively. Further studies are needed to clinically evaluate these formulations in early-stage COVID-19 patients.

Molecular design strategies of multifunctional probe for simultaneous monitoring of Cu2+, Al3+, Ca2+ and endogenous l-phenylalanine (LPA) recognition in living cells and zebrafishes

An innovative strategy of adjusting the molecular polarity of organics is applied for multifunctional simultaneous ions detection. It involved the use of 4-bromo-2-hydroxyben Rhodamine B hydrazide (RHBr) as a colorimetric and fluorescent multifunctional chemosensor. Briefly, it was designed and prepared via integrating 4-bromo-2-hydroxybenzaldehyde with Rhodamine B hydrazide, and Rhodamine B as fluorophore group, CO, -CHN and -OH groups as reaction site, Br atom as electro n-withdrawing group. On the basis of theoretical calculation under Gaussian 09 software suit, RHBr could exclusively recognize Cu²⁺, Al³⁺ and Ca²⁺. This was also experimentally confirmed by the different turn-on colorimetric and fluorescent signals. For example the selective detection of Cu²⁺ ion in DMSO/H₂O (1/1 = v/v, 10.0 mM HEPES pH 7.0) with the "naked-eye" when the color changed from colorless to pink, Al³⁺ with "turn-on" strong orange-red fluorescence and Ca²⁺ with strong green fluorescence in EtOH/H₂O (v/v = 95/5). Under the optimized conditions, all the ions could be detected at a very low concentrations (1.7 × 10^-7 M, 1.0 × 10^-8 M, 2.8 × 10^-7 M for Cu²⁺, Al³⁺, and Ca²⁺, respectively). In addition, the "in situ" formed RHBr-Al³⁺ was used to recognize l-phenylalanine (LPA) with a "turn-off" fluorescence ranging from 0.03-10.0 μM with the low detection concetration of 3.0 × 10^-7 M. The sensing mechanisms of RHBr toward three metal ions and the ensemble RHBr-Al³⁺ toward the l-phenylalanine (LPA) were further investigated in detail. Practical application experiments further proved that RHBr had good cell permeability and could be utilized to detect Al³⁺ and Ca²⁺, and the complexes of RHBr-Al³⁺ could be applied to detect l-phenylalanine (LPA) in the living cells and zebrafishes, respectively.

Accelerated evolution of an Lhx2 enhancer shapes mammalian social hierarchies

Social hierarchies emerged during evolution, and social rank influences behavior and health of individuals. However, the evolutionary mechanisms of social hierarchy are still unknown in amniotes. Here we developed a new method and performed a genome-wide screening for identifying regions with accelerated evolution in the ancestral lineage of placental mammals, where mammalian social hierarchies might have initially evolved. Then functional analyses were conducted for the most accelerated region designated as placental-accelerated sequence 1 (PAS1, P = 3.15 × 10-18). Multiple pieces of evidence show that PAS1 is an enhancer of the transcription factor gene Lhx2 involved in brain development. PAS1s isolated from various amniotes showed different cis-regulatory activity in vitro, and affected the expression of Lhx2 differently in the nervous system of mouse embryos. PAS1 knock-out mice lack social stratification. PAS1 knock-in mouse models demonstrate that PAS1s determine the social dominance and subordinate of adult mice, and that social ranks could even be turned over by mutated PAS1. All homozygous mutant mice had normal huddled sleeping behavior, motor coordination and strength. Therefore, PAS1-Lhx2 modulates social hierarchies and is essential for establishing social stratification in amniotes, and positive Darwinian selection on PAS1 plays pivotal roles in the occurrence of mammalian social hierarchies.

Inhibition of XBP1s ubiquitination enhances its protein stability and improves glucose homeostasis

BACKGROUND

Hepatic ER stress is a risk factor of insulin resistance and type 2 diabetes. X-box binding protein 1 spliced (XBP1s), a transcription factor, plays a key role in ameliorating insulin resistance and maintaining glucose homeostasis. Unfortunately, the short half-life of the protein dampens its clinical application, and the specific site of lysine residue that could be ubiquitinated and involved in the degradation of XBP1s remains elusive.

METHODS AND RESULTS

Here, we identified K60 and K77 on XBP1s as two pivotal ubiquitin sites required for its proteasome-dependent degradation. We also constructed a double mutant form of XBP1s (K60/77R) and found that it showed higher capacity in resisting against ubiquitin-mediated protein degradation, increasing nuclear translocation, enhancing transcriptional activity, suppressing ER stress and promoting Foxo1 degradation, compared to that of wild type XBP1s (WT). Consistently, overexpression of the K60/77R XBP1s mutant in DIO mice increased the ability to reduce ER stress and decrease Foxo1 levels, thus contributed to maintaining glucose homeostasis.

CONCLUSION

Our results suggest that delaying the degradation of XBP1s by preventing ubiquitination might provide a strategic approach for reducing ER stress as an anti-diabetes therapy.

Indirubin, a small molecular deriving from connectivity map (CMAP) screening, ameliorates obesity-induced metabolic dysfunction by enhancing brown adipose thermogenesis and white adipose browning

Background

Obesity occurs when the body’s energy intake is constantly greater than its energy consumption and the pharmacological enhancing the activity of brown adipose tissue (BAT) and (or) browning of white adipose tissue (WAT) has been considered promising strategies to treat obesity.

Methods

In this study, we took a multi-pronged approach to screen UCP1 activators, including in silico predictions, in vitro assays, as well as in vivo experiments.

Results

Base on Connectivity MAP (CMAP) screening, we obtained multiple drugs that possess a remarkably correlating gene expression pattern to that of enhancing activity in BAT and (or) sWAT signature. Particularly, we focused on a previously unreported drug-indirubin, a compound obtained from the Indigo plant, which is now mainly used for the treatment of chronic myelogenous leukemia (CML). In the current study, our results shown that indirubin could enhance the BAT activity, as evidenced by up-regulated Ucp1 expression and enhanced mitochondrial respiratory function in vitro cellular model. Furthermore, indirubin treatment restrained high-fat diet (HFD)-induced body weight gain, improved glucose homeostasis and ameliorated hepatic steatosis which were associated with the increase of energy expenditure in the mice model. Moreover, we revealed that indirubin treatment increased BAT activity by promoting thermogenesis and mitochondrial biogenesis in BAT and induced browning of subcutaneous inguinal white adipose tissue (sWAT) of mice under HFD. Besides, our results indicated that indirubin induced UCP1 expression in brown adipocytes, at least in part, via activation of PKA and p38MAPK signaling pathways.

Conclusions

Our results clearly show that as an effective BAT (as well as beige cells) activator, indirubin may have a protective effect on the prevention and treatment of obesity and its complications.

NMR-based Structural Classification, Identification, and Quantification of Triterpenoids from Edible Mushroom Ganoderma resinaceum

Ganoderma mushrooms have been widely used as functional food in China, Japan, and Korea. Ganoderma triterpenoids are deemed to be the main functional constituents. The structures of Ganoderma triterpenoids are complex but quite similar, which makes their analyses markedly limited. In this study, we developed a general 2D NMR method to differentiate Ganoderma triterpenoids, which classifies them into six types (A-F). Then, by the NMR-based isolation of A-F type triterpenoids from the fruiting bodies of G. resinaceum, four new compounds (1-4) and eight known compounds (5-12) were obtained. Moreover, combined with spiking experiments in 1D and 2D NMR spectra, compounds 5, 7, and 8, which belong to triterpenoids of A and B types, were identified. At the end, to achieve a more extensive application for this NMR method, a qNMR method for the absolute quantification of 5, 7, and 8 in the gross triterpenoids from G. resinaceum was set up. The results showed that this NMR method is reliable for the NMR-guided isolation and quantification of triterpenoids in G. resinaceum.

Coordinated regulation of infection-related morphogenesis by the KMT2-Cre1-Hyd4 regulatory pathway to facilitate fungal infection

Entomopathogenic fungi can overcome insecticide resistance and represent promising tools for the control of mosquitoes. Better understanding of fungus-mosquito interactions is critical for improvement of fungal efficacy. Upon insect cuticle induction, pathogenic fungi undergo marked infection-related morphological differentiation. However, regulatory mechanisms of fungal infection-related morphogenesis are poorly understood. Here, we show that a histone lysine methyltransferase KMT2 in Metarhizium robertsii (MrKMT2) is up-regulated upon cuticle induction. MrKMT2 plays crucial roles in regulating infection-related morphogenesis and pathogenicity by up-regulating the transcription factor gene Mrcre1 via H3K4 trimethylation during mosquito cuticle infection. MrCre1 further regulates the cuticle-induced gene Mrhyd4 to modulate infection structure (appressorium) formation and virulence. Overall, the MrKMT2-MrCre1-MrHyd4 regulatory pathway regulates infection-related morphogenesis and pathogenicity in M. robertsii. These findings reveal that the epigenetic regulatory mechanism plays a pivotal role in regulating fungal pathogenesis in insects, and provide new insights into molecular interactions between pathogenic fungi and insect hosts.

Corilagin Alleviates Nonalcoholic Fatty Liver Disease in High-Fat Diet-Induced C57BL/6 Mice by Ameliorating Oxidative Stress and Restoring Autophagic Flux

Corilagin (Cori) possesses multiple biological activities. To determine whether Cori can exert protective effects against nonalcoholic fatty liver disease (NAFLD) and its potential mechanisms. C57BL/6 mice were fed with high-fat diet (HFD) alone or in combination with Cori (20 mg/kg, i.p.) and AML12 cells were exposed to 200 μM PA/OA with or without Cori (10 μM or 20 μM). Phenotypes and key indicators relevant to NAFLD were examined both in vivo and in vitro. In this study, Cori significantly ameliorated hepatic steatosis, confirmed by improved serum lipid profiles, and hepatic TC, TG contents, and the gene expression related to lipid metabolism in livers of HFD mice. Moreover, Cori attenuated HFD-mediated autophagy (including mitophagy) blockage by restoring autophagic flux, evidenced by increased number of autophagic double vesicles containing mitochondria, elevated LC3II protein levels, decreased p62 protein levels, as well as enhanced colocalization of autophagy-related protein (LC3, Parkin) and mitochondria. In accordance with this, Cori also reduced the accumulation of ROS and MDA levels, and enhanced the activities of antioxidative enzymes including SOD, GSH-Px, and CAT. In addition, Cori treatment improved mitochondrial dysfunction, evidenced by increased mitochondrial membrane potential (ΔΨm). In parallel with this, Cori decreased mitochondrial DNA oxidative damage, while increased mitochondrial biogenesis related transcription factors expression, mitochondrial DNA content and oxygen consumption rate (OCR). In conclusion, these results demonstrate that Cori is a potential candidate for the treatment of NAFLD via diminishing oxidative stress, restoring autophagic flux, as well as improving mitochondrial functions.

Efficient Polymer Pendant Approach toward High Stable Organic Fluorophore for Sensing Ultratrace Hg2+ with Improved Biological Compatibility and Cell Permeability

A convenient and efficient method to eliminate the aggregation effect of organic photoelectric sensing materials and to improve biological compatibility and cell permeability as well was developed by hanging organic fluorophores on a polymer chain, for example, fluorescein fluorophores had been controllably hung on polyacrylamide main chains with a 1:2 stoichiometric ratio by a simple copolymerization strategy. The results showed that introduction of water-soluble bioactive polyacrylamide main chains into fluorescein fluorophores via covalent bonds could effectively improve their optical stability by deteriorating π-π stack and charge-transfer interactions among different fluorophores. More importantly, the resultant materials possessed low toxicity and excellent cell permeability ten times larger than their precursor fluorescein fluorophore, which made it express an especially turn-on fluorescent response to ultratrace Hg²⁺ both in aqueous and living cells by forming stable 5-member-ring complexes with Hg²⁺ with a correlation coefficient of 0.997 and a low detection limit of 4.0 × 10^-10 mol·L^-1. This work provides promising insight into constructing some practical sensing materials for environmentally-friendly biological analyses.

A new species of the Music frog Nidirana (Anura, Ranidae) from Guizhou Province, China

The Music frog genus Nidirana is widely distributed in East and South Asia. Here, a new species of the genus is described from southwestern China. Phylogenetic analyses based on the mitochondrial 16S rRNA and COI gene sequences supported the new species as a clade closely related to N. leishanensis, N. hainanensis, N. chapaensis, N. daunchina, and N. yaoica. The new species could be distinguished from its congeners by a combination of the following characters: body of medium size (SVL 41.2-43.5 mm in males and 44.7 mm in female); lateroventral groove only present on toes; relative finger lengths: II < IV < I < III; three metatarsal tubercles on palm; heels overlapping when hindlimbs flexed at right angles to axis of body; tibiotarsal articulation reaching the level of eye when leg stretched forward; a pair of subgular internal vocal sacs at corners of throat in male; nuptial pad present on the inner side of base of fingers I in breeding male; tadpole labial tooth row formula with 1:1+1/1+1:2; in males, the advertisement call contains two kinds of notes and one call contains 2-6 repeated regular notes.

Thorium(iv) and uranium(vi) compounds of cucurbit[10]uril: from a one-dimensional nanotube to a supramolecular framework

Cucurbit[10]uril {Q[10]} has the largest portal size and cavity in the series of Q[n] (n = 5-10) molecules. In contrast to its rich host-guest chemistry, its coordination chemistry is underdeveloped with only limited metal ions being investigated so far. In this work, we initiated the study of Q[10] complexes with Th(iv) and U(vi) ions in HCl solutions via a self-assembly approach. The coordination of Th(iv) ions with Q[10] led to the formation of a compound, {Th4(Cl)16(H2O)20(Q[10])}·nH2O (Q[10]-Th), with a unique nano-tubular structure, while U(vi) ions facilitated the formation of a compound, [(UO2)2(Cl)4(H2O)6]·(Q[10])2·HCl·nH2O (Q[10]-U), with a Q[10]-based supramolecular framework structure via intermolecular outer-surface and second-shell interactions. The structural and spectroscopic aspects of the two compounds together with their optical and thermal properties have been investigated. The successful preparation and characterization of the first two Q[10] compounds with Th(iv)/U(vi) ions highlighted the potential for further exploration of Q[10] coordination chemistry with actinide ions.

A colorimetric chemosensor for quantification of exchangeable Cu2+ in soil

Chemosensors have already demonstrated potential for the detection and imaging of metal ions in solutions and biological systems, however, their applications to soil analysis are limited. This study explores the potential of utilizing a chemosensor for the detection of exchangeable Cu²⁺ in soils via qualitative (solution visual color change) and quantitative (UV-Vis spectrophotometry) approaches. Montmorillonite and kaolin clays were doped with Cu(NO₃)₂ solutions from 2.5 to 50 mM, and contaminated soil samples were collected from a historic copper mine. The exchangeable Cu²⁺ was extracted using a standard CaCl₂ cation exchange approach, and the Cu²⁺ concentration in the resulting solutions determined by UV-Vis spectrophotometry, using a chemosensor, and compared to traditional ICP-MS analysis. Analytical results showed that the chemosensor provided a visual response in contaminated soils at concentrations of 25 μM and quantitative detection to concentrations of 1 μM using UV-Vis spectrophotometry. This work demonstrates the first reported chemosensor for exchangeable Cu²⁺ with application to soil systems.

Reassortment of Genome Segments Creates Stable Lineages Among Strains of Orchid Fleck Virus Infecting Citrus in Mexico

The genus Dichorhavirus contains viruses with bipartite, negative-sense, single-stranded RNA genomes that are transmitted by flat mites to hosts that include orchids, coffee, the genus Clerodendrum, and citrus. A dichorhavirus infecting citrus in Mexico is classified as a citrus strain of orchid fleck virus (OFV-Cit). We previously used RNA sequencing technologies on OFV-Cit samples from Mexico to develop an OFV-Cit-specific reverse transcription PCR (RT-PCR) assay. During assay validation, OFV-Cit-specific RT-PCR failed to produce an amplicon from some samples with clear symptoms of OFV-Cit. Characterization of this virus revealed that dichorhavirus-like particles were found in the nucleus. High-throughput sequencing of small RNAs from these citrus plants revealed a novel citrus strain of OFV, OFV-Cit2. Sequence comparisons with known orchid and citrus strains of OFV showed variation in the protein products encoded by genome segment 1 (RNA1). Strains of OFV clustered together based on host of origin, whether orchid or citrus, and were clearly separated from other dichorhaviruses described from infected citrus in Brazil. The variation in RNA1 between the original (now OFV-Cit1) and the new (OFV-Cit2) strain was not observed with genome segment 2 (RNA2), but instead, a common RNA2 molecule was shared among strains of OFV-Cit1 and -Cit2, a situation strikingly similar to OFV infecting orchids. We also collected mites at the affected groves, identified them as Brevipalpus californicus sensu stricto, and confirmed that they were infected by OFV-Cit1 or with both OFV-Cit1 and -Cit2. OFV-Cit1 and -Cit2 have coexisted at the same site in Toliman, Queretaro, Mexico since 2012. OFV strain-specific diagnostic tests were developed.

Yttrium and lanthanide (Ln = La and Gd) complexes with cucurbit[10]uril: crystals transforming from supramolecular frameworks to coordination nanotubes

Yttrium and lanthanide complexes with cucurbit[10]uril have been investigated with crystals transforming from supramolecular structures to coordination nanotubes being revealed.

Enzyme-mediated reversible deactivation radical polymerization for functional materials: principles, synthesis, and applications

Enzymes provide a potential and highly efficient way to mediate the formation of various functional polymer materials with wide applications.

Enhanced β-glucan and pullulan production by Aureobasidium pullulans with zinc sulfate supplementation

The effects of mineral salts on the production of exopolysaccharides, including β-glucan and pullulan, by Aureobasidium pullulans CCTCC M 2012259 were investigated. Zinc sulfate at certain concentrations decreased dry biomass but favored to the biosynthesis of both exopolysaccharides. When 100 mg/L zinc sulfate was added to the fermentation medium, production of β-glucan and pullulan increased by 141.7 and 10.2%, respectively, when compared with that noted in the control without zinc sulfate addition. To reveal the physiological mechanism underlying improved β-glucan and pullulan production, key enzymes activities, energy metabolism substances, intracellular uridine diphosphate glucose (UDPG) levels, and gene expression were determined. The results indicated that zinc sulfate up-regulated the transcriptional levels of pgm1, ugp, fks, and kre6 genes, increased activities of key enzymes involved in the biosynthesis of UDPG, β-glucan and pullulan, enhanced intracellular UDPG content, and improved energy supply, all of which contributed to the increment in β-glucan and pullulan production. The present study not only provides a feasible approach to improve the production of exopolysaccharides but also contributes to better understanding of the physiological characteristics of A. pullulans.

Recent progress in drug delivery

Drug delivery systems (DDS) are defined as methods by which drugs are delivered to desired tissues, organs, cells and subcellular organs for drug release and absorption through a variety of drug carriers. Its usual purpose to improve the pharmacological activities of therapeutic drugs and to overcome problems such as limited solubility, drug aggregation, low bioavailability, poor biodistribution, lack of selectivity, or to reduce the side effects of therapeutic drugs. During 2015-2018, significant progress in the research on drug delivery systems has been achieved along with advances in related fields, such as pharmaceutical sciences, material sciences and biomedical sciences. This review provides a concise overview of current progress in this research area through its focus on the delivery strategies, construction techniques and specific examples. It is a valuable reference for pharmaceutical scientists who want to learn more about the design of drug delivery systems.

Tanshinone IIA reverses EGF- and TGF-β1-mediated epithelial-mesenchymal transition in HepG2 cells via the PI3K/Akt/ERK signaling pathway

Epithelial-to-mesenchymal transition (EMT) is an essential phenotypic conversion involved in cancer progression. Epidermal growth factor (EGF) and transforming growth factor (TGF)-β1 are potent inducers of the EMT. Tanshinone IIA (Tan IIA) is a phenanthrenequinone extracted from the root of Salvia miltiorrhiza Bunge, and its anticancer activity has been demonstrated in numerous studies. However, the mechanisms of action underlying Tan IIA in EGF- and TGF-β1-induced EMT in HepG2 cells remain unknown. Multiple assays were utilized in the present study, including colony formation, wound healing, Transwell invasion, immunofluorescence staining and western blotting, in order to assess the influence of Tan IIA on HepG2 cells induced by 20 ng/ml EGF and 10 ng/ml TGF-β1. The present study reported that Tan IIA treatment decreased EGF- and TGF-β1-enhanced cell colony numbers, migration and invasion, and inhibited EGF- and TGF-β1-induced decreases in the expression levels of E-cadherin, and increases in the expression levels of matrix metalloproteinase-2, N-cadherin, vimentin and Snail. In addition, it was observed that Tan IIA decreased the expression levels of phosphorylated (p)-Akt and p-ERK1/2 induced by EGF and TGF-β1. Furthermore, western blot analysis confirmed that blocking the function of PI3K/Akt and ERK with LY294002 and U0126 resulted in upregulation of E-cadherin expression, and downregulation of vimentin and Snail expression in EGF- and TGF-β1-treated HepG2 cells. In conclusion, to the best of our knowledge, the results of the present study are the first to indicate that Tan IIA may suppress EGF- and TGF-β1-induced EMT in HepG2 cells by deactivating the PI3K/Akt/ERK pathway.

The anticoagulants rivaroxaban and low molecular weight heparin prevent PICC-related upper extremity venous thrombosis in cancer patients

Peripherally inserted central catheter (PICC) is often applied in chemotherapy patients and commonly causes upper extremity venous thrombosis (UEVT), which should be prevented.To assess the preventive effects of the anticoagulants rivaroxaban and low molecular weight heparin (LMWH) on UEVT in patients receiving chemotherapy through PICCs.A total of 423 chemotherapy patients with continuous PICC use between January 2014 and June 2015 at the Oncology Department of Dongying People's Hospital were divided into 3 groups: rivaroxaban (10 mg/day, orally), LMWH (Enoxaparine, 4000 anti-Xa IU/day, subcutaneous injection), and control (no anticoagulant). UEVT incidence and other complications during PICC use were observed and recorded.The rivaroxaban, LMWH, and control groups included 138 (79 males; 54.9 ± 11.0 years), 144 (76 males; 56.0 ± 10.9 years), and 141 (71 males; 53.3 ± 10.9 years) patients, (P = .402 and P = .623 for age and sex respectively). There were no differences in cancer location (P = .628), PICC implantation site (P > .05), body mass index (BMI) (P = .434), blood pressure (all P > .05), blood lipids (5 laboratory parameters included, all P > .5), smoking (P = .138), history of lower limb venous thrombosis (P = .082), and 10 other associated comorbidities (all P > .5). Twenty-nine patients withdrew from the study (5 from the rivaroxaban, 12 from the LMWH, and 12 from the control groups, respectively), and 394 patients were analyzed. There were significant differences in the rivaroxaban group and the LMWH group compared to the control group (P = .010 and P = .009, respectively), but no significant difference was observed between the rivaroxaban group and the LMWH group (P = .743).Anticoagulants such as rivaroxaban and LMWH may reduce the incidence of PICC-related UEVT in patients receiving chemotherapy.

The Nuclear Matrix Protein SAFB Cooperates with Major Satellite RNAs to Stabilize Heterochromatin Architecture Partially through Phase Separation

Interphase chromatin is hierarchically organized into higher-order architectures that are essential for gene functions, yet the biomolecules that regulate these 3D architectures remain poorly understood. Here, we show that scaffold attachment factor B (SAFB), a nuclear matrix (NM)-associated protein with RNA-binding functions, modulates chromatin condensation and stabilizes heterochromatin foci in mouse cells. SAFB interacts via its R/G-rich region with heterochromatin-associated repeat transcripts such as major satellite RNAs, which promote the phase separation driven by SAFB. Depletion of SAFB leads to changes in 3D genome organization, including an increase in interchromosomal interactions adjacent to pericentromeric heterochromatin and a decrease in genomic compartmentalization, which could result from the decondensation of pericentromeric heterochromatin. Collectively, we reveal the integrated roles of NM-associated proteins and repeat RNAs in the 3D organization of heterochromatin, which may shed light on the molecular mechanisms of nuclear architecture organization.

A multiple fluorescein-based turn-on fluorophore (FHCS) identified for simultaneous determination and living imaging of toxic Al3+ and Zn2+ by improved Stokes shift

A multiple turn-on fluorophore (FHCS), combining fluorescein, hydrazone, cyanuric chloride and salicylaldehyde chromone into a molecule, was identified and developed based on density functional theoretical calculation. It was expected that FHCS could express exclusive fluorescent signals and improved Stokes shifts when chelating Al³⁺ or Zn²⁺. After it was synthesized and characterized in detail, it was noted that FHCS could turn-on fluorescently discriminate trace Al³⁺ and Zn²⁺ under the optimized conditions, i.e., from no-fluorescence to strong blue fluorescence for Al³⁺ and to green fluorescence for Zn²⁺ with low detection limits of 5.37 × 10^-8 M and 7.90 × 10^-8 M respectively. Owing to its low toxicity, FHCS was successfully applied for quantitative determination of Al³⁺ and Zn²⁺ in natural aqueous samples and toxicity evaluation of Al³⁺ and Zn²⁺ in living cells and bio-tissues with excellent linear relationships. The action mechanisms for FHCS with Al³⁺ and Zn²⁺ were confirmed to form stable 5-member-co-6-member condensed rings between Al³⁺/Zn²⁺ and N/O atoms in FHCS by both theoretic and experimental methods, which resulted in turn-on fluorescence with different dipolar moments and improved Stokes shifts.

Imminent extinction in the wild of the world's largest amphibian

Species with large geographic ranges are considered resilient to global decline [1]. However, human pressures on biodiversity affect increasingly large areas, in particular across Asia, where market forces drive overexploitation of species [2]. Range-wide threat assessments are often costly and thus extrapolated from non-representative local studies [3]. The Chinese giant salamander (Andrias davidianus), the world's largest amphibian, is thought to occur across much of China, but populations are harvested for farming as luxury food [4]. Between 2013 and 2016, we conducted field surveys and 2,872 interviews in possibly the largest wildlife survey conducted in China. This extensive effort revealed that populations of this once-widespread species are now critically depleted or extirpated across all surveyed areas of their range, and illegal poaching is widespread.

Identification of the perpetrator among identical twins using next-generation sequencing technology: A case report

BACKGROUND

Monozygotic (MZ) twins, considered genetically identical, cannot be distinguished using regular short tandem repeats (STR) typing, thus presenting a challenge for forensic geneticists. In paternity testing, single nucleotide polymorphisms (SNPs) in nuclear DNA can help distinguish MZ twins. However, the unique features of the mitochondrial genome, such as high copy number, small genome size, and high substitution rate, make it a promising source for applications in forensic science.

METHODS

Whole-genome sequencing (WGS) was performed on blood samples, and bioinformatic analysis was used to distinguish between MZ twins. Amplification refractory mutation system polymerase chain reaction (ARMS-PCR) was used to confirm the WGS results. This methodology was further applied to forensic samples from criminal cases. Amplicon sequencing was also performed to further exclude the innocent twin.

RESULTS

The monozygosity of the twins was confirmed using STR typing. Only one potential somatic mutation, m.6903 T > C (2.6%), in the mitochondrial genome of one of the twins was verified when the sequence depth was set to 2000-fold, while no other distinguishing locus in the nuclear genome was identified. By dividing the number of C-reads by total reads, WGS data confirmed the amount of the minor component C to be 2.6%, which was further confirmed by ARMS-PCR. In addition, the heterogeneous locus was used to identify samples obtained from four criminal cases for forensic testing. Two heterogeneous loci in the sperm DNA of the other twin were identified by amplicon sequencing, and the amount of minor component T in m.6935C > T and m.6938C > T was estimated to be 17.91% and 18.79%, respectively.

CONCLUSION

The biological samples taken from the MZ twins were distinguished using a combination of WGS, allele-specific PCR, and deep-amplicon sequencing. Compared with nuclear DNA, mitochondrial DNA exhibited a higher potential for distinguishing between the MZ twins. The distinguishing feature of the mitochondrial DNA was the heterogeneous SNPs that occurred in only one twin. One SNP was further verified in the samples from the criminal cases and helped identify the perpetrator in case 1 and case 2. Furthermore, two heterogeneous SNPs found by amplicon sequencing helped to exclude the innocent twin in all four cases. Our findings demonstrated that a combination of deep sequencing and molecular analysis can be an effective way to distinguish between identical twins and can be used to analyze samples from criminal cases.

Biomimetic Hydroxyapatite on Graphene Supports for Biomedical Applications: A Review

Hydroxyapatite (HA) has been widely used in fields of materials science, tissue engineering, biomedicine, energy and environmental science, and analytical science due to its simple preparation, low-cost, and high biocompatibility. To overcome the weak mechanical properties of pure HA, various reinforcing materials were incorporated with HA to form high-performance composite materials. Due to the unique structural, biological, electrical, mechanical, thermal, and optical properties, graphene has exhibited great potentials for supporting the biomimetic synthesis of HA. In this review, we present recent advance in the biomimetic synthesis of HA on graphene supports for biomedical applications. More focuses on the biomimetic synthesis methods of HA and HA on graphene supports, as well as the biomedical applications of biomimetic graphene-HA nanohybrids in drug delivery, cell growth, bone regeneration, biosensors, and antibacterial test are performed. We believe that this review is state-of-the-art, and it will be valuable for readers to understand the biomimetic synthesis mechanisms of HA and other bioactive minerals, at the same time it can inspire the design and synthesis of graphene-based novel nanomaterials for advanced applications.

The Design and Synthesis of Fluorescent Coumarin Derivatives and Their Study for Cu2+ Sensing with an Application for Aqueous Soil Extracts

A series of fluorescent coumarin derivatives 2a–e were systematically designed, synthesized and studied for their Cu²⁺ sensing performance in aqueous media. The sensitivities and selectivities of the on-to-off fluorescent Cu²⁺ sensing signal were in direct correlation with the relative arrangements of the heteroatoms within the coordinating moieties of these coumarins. Probes 2b and 2d exhibited Cu²⁺ concentration dependent and selective fluorescence quenching, with linear ranges of 0–80 μM and 0–10 μM, and limits of detection of 0.14 μM and 0.38 μM, respectively. Structural changes of 2b upon Cu²⁺ coordination were followed by fluorescence titration, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), mass spectrometry, and single crystal X-ray diffraction on the isolated Cu²⁺-coumarin complex. The results revealed a 1:1 stoichiometry between 2b and Cu²⁺, and that the essential structural features for Cu²⁺-selective coordination are the coumarin C=O and a three-bond distance between the amide NH and heterocyclic N. Probe 2b was also used to determine copper (II) levels in aqueous soil extracts, with recovery rates over 80% when compared to the standard soil analysis method: inductively coupled plasma-mass spectrometry (ICP-MS).

Electrospinning Nanoparticles-Based Materials Interfaces for Sensor Applications

Electrospinning is a facile technique to fabricate nanofibrous materials with adjustable structure, property, and functions. Electrospun materials have exhibited wide applications in the fields of materials science, biomedicine, tissue engineering, energy storage, environmental science, sensing, and others. In this review, we present recent advance in the fabrication of nanoparticles (NPs)-based materials interfaces through electrospinning technique and their applications for high-performance sensors. To achieve this aim, first the strategies for fabricating various materials interfaces through electrospinning NPs, such as metallic, oxide, alloy/metal oxide, and carbon NPs, are demonstrated and discussed, and then the sensor applications of the fabricated NPs-based materials interfaces in electrochemical, electric, fluorescent, colorimetric, surface-enhanced Raman scattering, photoelectric, and chemoresistance-based sensing and detection are presented and discussed in detail. We believe that this study will be helpful for readers to understand the fabrication of functional materials interfaces by electrospinning, and at the same time will promote the design and fabrication of electrospun nano/micro-devices for wider applications in bioanalysis and label-free sensors.

Octopus-like Flexible Vector for Noninvasive Intraocular Delivery of Short Interfering Nucleic Acids

Gene therapy is promising for chronic posterior ocular diseases, which are causal factors for severe vision impairment and even blindness worldwide. However, the inherent absorption barriers of the eye restrict intraocular delivery of therapeutic nucleic acids via topical instillation. Safe and efficient nonviral vectors for ocular gene therapy are still unmet clinical desires. Herein, an octopus-like flexible multivalent penetratin (MVP) was designed to facilitate condensation and delivery of therapeutic nucleic acids using multiarm polyethylene glycol (PEG) as a core and conjugating penetratin at each end of the PEG arms as outspread tentacles. Among the MVPs, 8-valent penetratin (8VP) stably compacted nucleic acids into positively charged polyplexes smaller than 100 nm, promoting cellular uptake efficiency (approaching 100%) and transfection rate (over 75%). After being instilled into the conjunctival sac, 8VP enabled rapid (<10 min) and prolonged (>6 h) distribution of nucleic acids in the retina via a noncorneal pathway. In a retinoblastoma-bearing mice model, topical instillation of 8VP/siRNA efficiently inhibited the protein expression of intraocular tumor without toxicity. MVP is advantageous over the commercial transfection reagent in safety and efficiency, and therefore provides a promising vector for noninvasive intraocular gene delivery.

SMYD2 Drives Mesendodermal Differentiation of Human Embryonic Stem Cells Through Mediating the Transcriptional Activation of Key Mesendodermal Genes

Histone methyltransferases play a critical role in early human development, whereas their roles and precise mechanisms are less understood. SET and MYND domain-containing protein 2 (SMYD2) is a histone lysine methyltransferase induced during early differentiation of human embryonic stem cells (hESCs), but little is known about its function in undifferentiated hESCs and in their early lineage fate decision as well as underlying mechanisms. Here, we explored the role of SMYD2 in the self-renewal and mesendodermal lineage commitment of hESCs. We demonstrated that the expression of SMYD2 was significantly enhanced during mesendodermal but not neuroectodermal differentiation of hESCs. SMYD2 knockout (SMYD2^-/- ) did not affect self-renewal and early neuroectodermal differentiation of hESCs, whereas it blocked the mesendodermal lineage commitment. This phenotype was rescued by reintroduction of SMYD2 into the SMYD2^-/- hESCs. Mechanistically, the bindings of SMYD2 at the promoter regions of critical mesendodermal transcription factor genes, namely, brachyury (T), eomesodermin (EOMES), mix paired-like homeobox (MIXL1), and goosecoid homeobox (GSC) were significantly enhanced during mesendodermal differentiation of SMYD2^+/+ hESCs but totally suppressed in SMYD2^-/- ones. Concomitantly, such a suppression was associated with the remarkable reduction of methylation at histone 3 lysine 4 and lysine 36 but not at histone 4 lysine 20 globally and specifically on the promoter regions of mesendodermal genes, namely, T, EOMES, MIXL1, and GSC. These results reveal that the histone methyltransferase SMYD2 is dispensable in the undifferentiated hESCs and the early neuroectodermal differentiation, but it promotes the mesendodermal differentiation of hESCs through the epigenetic control of critical genes to mesendodermal lineage commitment. Stem Cells 2019;37:1401-1415.

Synthesis of Three-Dimensional Graphene-Based Hybrid Materials for Water Purification: A Review

Graphene-based nanostructures and nanomaterials have been widely used for the applications in materials science, biomedicine, tissue engineering, sensors, energy, catalysis, and environmental science due to their unique physical, chemical, and electronic properties. Compared to two-dimensional (2D) graphene materials, three-dimensional (3D) graphene-based hybrid materials (GBHMs) exhibited higher surface area and special porous structure, making them excellent candidates for practical applications in water purification. In this work, we present recent advances in the synthesis and water remediation applications of 3D GBHMs. More details on the synthesis strategies of GBHMs, the water treatment techniques, and the adsorption/removal of various pollutants from water systems with GBHMs are demonstrated and discussed. It is expected that this work will attract wide interests on the structural design and facile synthesis of novel 3D GBHMs, and promote the advanced applications of 3D GBHMs in energy and environmental fields.

Identification of C-glycosyl flavones by high performance liquid chromatography electrospray ionization mass spectrometry and quantification of five main C-glycosyl flavones in Flickingeria fimbriata

Flickingeria fimbriata is commonly applied in China as a traditional Chinese medicine (TCM), however the quality control of it is incomplete. In this work, we aim to identify and quantify the structures of C-glycosyl flavones in F. fimbriata. High performance liquid chromatography-diode array detector (HPLC-DAD) and High performance liquid chromatography–electrospray ionization–multiple stage tandem mass spectrometry (HPLC–ESI–MSⁿ) methods were combined to identify C-glycosyl flavones and determine their contents. Twenty acylated C-glycosyl flavones and ten non-acylated C-glycosyl flavones were identified for the first time in F. fimbriata on systematic MSⁿ analysis via HPLC–ESI–MSⁿ. The aglycones of all of these compounds were apigenin or chrysoeriol and were acylated with p-coumaric, ferulic, 3,4-dimethoxycinnamic or 3,4,5-trimethoxycinnamic acids. Furthermore, the quantification result suggest that two C-glycosyl flavones (vicenin-I and vicenin-III) with relative high contents were revealed to be more strongly acylated in F. fimbriata. The method is sufficiently precise, accurate, and sensitive for the qualitative and quantitative analysis of C-glycosyl flavones, which is expected to establish a standard for quality control and identification in this plant.

Carbon Nanofiber-Based Functional Nanomaterials for Sensor Applications

Carbon nanofibers (CNFs) exhibit great potentials in the fields of materials science, biomedicine, tissue engineering, catalysis, energy, environmental science, and analytical science due to their unique physical and chemical properties. Usually, CNFs with flat, mesoporous, and porous surfaces can be synthesized by chemical vapor deposition and electrospinning techniques with subsequent chemical treatment. Meanwhile, the surfaces of CNFs are easy to modify with various materials to extend the applications of CNF-based hybrid nanomaterials in multiple fields. In this review, we focus on the design, synthesis, and sensor applications of CNF-based functional nanomaterials. The fabrication strategies of CNF-based functional nanomaterials by adding metallic nanoparticles (NPs), metal oxide NPs, alloy, silica, polymers, and others into CNFs are introduced and discussed. In addition, the sensor applications of CNF-based nanomaterials for detecting gas, strain, pressure, small molecule, and biomacromolecules are demonstrated in detail. This work will be beneficial for the readers to understand the strategies for fabricating various CNF-based nanomaterials, and explore new applications in energy, catalysis, and environmental science.

A new species of the Asian music frog genus Nidirana (Amphibia, Anura, Ranidae) from Southwestern China

The Asian music frog genus Nidirana is widely distributed in East and Southeastern Asia. Systematic profiles of the group remain on debate, and cryptic species are expected especially in the species with wide distributional range. Here, we describe a new species of the genus from Southwestern China. Phylogenetic analyses based on mitochondrial DNA and nuclear DNA supported the new species as an independent clade nested into the Nidirana clade and sister to N. hainanensis. Morphologically, the new species could be distinguished from its congeners by a combination of the following characters: a large body size in males (SVL > 49 mm); the presence of lateroventral grooves both on fingers and toes; relative finger lengths: II < IV < I < III; tibiotarsal articulation reaching the level between eye and nostril when leg stretched forward; a pair of subgular internal vocal sacs at corners of throat in males; nuptial pad present on the inner side of base of fingers I and II in males in breading season; webbing formula: I 2 –21/3 II 2 –22/3 III 31/2 –32/3 IV 32/3 –3V. The findings provided a better knowledge on phylogenetic assignments of the genus Nidirana, and indicated future deeper investigations necessarily for exploring systematic settings of the group.