Catalytic Cycle of CMP-Sialic Acid Synthetase Illustrated by High-Resolution Protein Crystallography.

Cytidine 5'-monophosphate (CMP)-sialic acid synthetase (CSS) is an essential enzyme involved in the biosynthesis of carbohydrates and glycoconjugates containing sialic acids, a class of α-keto acids that are generally terminal key recognition residues by many proteins that play important biological and pathological roles. The CSS from (NmCSS) has been commonly used with other enzymes such as sialic acid aldolase and/or sialyltransferase in synthesizing a diverse array of compounds containing sialic acid or its naturally occurring and non-natural derivatives. To better understand its catalytic mechanism and substrate promiscuity, four NmCSS crystal structures trapped at various stages of the catalytic cycle with bound substrates, substrate analogues, and products have been obtained and are presented here.

Nitrogen application and different water regimes at booting stage improved yield and 2-acetyl-1-pyrroline (2AP) formation in fragrant rice.

Background: Water (W) and nitrogen (N) management generally cause regulations in the 2-acetyl-1-pyrroline (2AP) accumulation in fragrant rice; nevertheless, the feasibility of such management strategies at booting stage in improving 2AP accumulation has not been examined in details.

Methods: Field experiments were conducted in the early season (March-July) and repeated in the late season (July-November) in 2013. The treatments were applied urea (90 kg ha), calcium super phosphate (90 kg ha) and potassium chloride (195 kg ha) as basal fertilizer, and urea (65 kg ha) at tillering stage.

Enterococcus faecalis α1-2-mannosidase (EfMan-I): an efficient catalyst for glycoprotein N-glycan modification.

While multiple α 1-2-mannosidases are necessary for glycoprotein N-glycan maturation in vertebrates, a single bacterial α1-2-mannosidase can be sufficient to cleave all α1-2-linked mannose residues in host glycoprotein N-glycans. We report here the characterization and crystal structure of a new α1-2-mannosidase (EfMan-I) from Enterococcus faecalis, a Gram-positive opportunistic human pathogen. EfMan-I catalyzes the cleavage of α1-2-mannose from not only oligomannoses but also high-mannose-type N-glycans on glycoproteins.

Prognostic Significance of CIP2A in Esophagogastric Junction Adenocarcinoma: A Study of 65 Patients and a Meta-Analysis.

Background: The expression of the cancerous inhibitor protein phosphatase 2A (CIP2A) appears to be predictive of the prognosis of various solid tumors. However, the association between this protein and the risk of esophagogastric junction adenocarcinoma (EGJA) remains unclear. We investigated CIP2A expression and its clinical significance in EGJA and conducted a meta-analysis to explore the relationship between CIP2A and the prognosis of patients with solid tumors.

Antioxidative capacity is highly associated with the storage property of tuberous roots in different sweetpotato cultivars.

The activities and gene expression of antioxidative enzymes and the ROS content were analyzed in two typical storage-tolerant cultivars (Xushu 32 and Shangshu 19) and another two storage-sensitive cultivars (Yanshu 25 and Sushu 16) to explore the association between the storage capacity of sweetpotato (Ipomoea batatas (L.) Lam) and ROS scavenging capability. The storage roots of the storage-tolerant cultivars maintained higher activities and expression levels of antioxidative enzymes, including ascorbate peroxidase (APX), peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD); lower activity and expression of lipoxygenase (LOX); and lower accumulation of ROS metabolites compared with the storage-sensitive cultivars.

Luminescent properties and ratiometric optical thermometry of Ln-BDC-F compounds.

A series of luminescent lanthanide compounds with 2, 3, 5, 6-tetrafluoro-1, 4-benzenedicarboxylate (HBDC-F) acting as the organic ligand have been synthesized by solvothermal reaction. The terbium compound (C1: Tb-BDC-F) and europium compound (C7: Eu-BDC-F) exhibit intense green and red luminescence respectively upon excitation of the ligand at room temperature, which suggests that HBDC-F ligand can sensitize Tb and Eu ions effectively. The emitting color of the mixed lanthanide compounds is tunable from green to red in the mixed lanthanide compounds TbEu-BDC-F (x = 0.

Redox properties and dechlorination capacities of landfill-derived humic-like acids.

Electron transfer capacities (ETC) of humic-like acids (HLA) and their effects on dechlorination are dependent on their redox-active properties. Aging and minerals can affect the chemical compositions and structures of HLA. However, the underlying mechanism and the impacts on the dechlorination capacities of HLA are poorly understood.

Regioselective One-Pot Multienzyme (OPME) Chemoenzymatic Strategies for Systematic Synthesis of Sialyl Core 2 Glycans.

O-GalNAc glycans or mucin-type glycans are common protein post-translational modifications in eukaryotes. Core 2 O-GalNAc glycans are branched structures that are broadly distributed in glycoproteins and mucins of all types of cells. To better understand their biological roles, it is important to obtain structurally defined Core 2 O-GalNAc glycans.

C646 modulates inflammatory response and antibacterial activity of macrophage.

C646 is a newly discovered competitive p300/CREB-binding protein-specific inhibitor. Previous studies have shown its potential antitumor activity, but the immunomodulatory function of C646 remains largely unknown. In this study, we investigated the effects of C646 in cytokine expression and antibacterial activity in mouse macrophages.

The pubertal development mode of Chinese girls with turner syndrome undergoing hormone replacement therapy.

Background: Further knowledge about the pubertal development mode of girls with Turner syndrome (TS) who have undergone hormone replacement therapy (HRT) is beneficial to the proposal of an optimal HRT regimen. This study examined the pubertal development mode of girls with TS who underwent HRT and evaluated the characteristics of optimal sex induction therapy in girls with TS.

Method: We conducted a retrospective, longitudinal study over the past two decades at The First Affiliated Hospital, Sun Yat-sen University.

Discovery of novel pyrimidine-based benzothiazole derivatives as potent cyclin-dependent kinase 2 inhibitors with anticancer activity.

To develop novel CDK2 inhibitors as anticancer agents, a series of novel pyrimidine-based benzothiazole derivatives were designed and synthesized. Initial biological evaluation demonstrated some of target compounds displayed potent antitumor activity in vitro against five cancer cell lines. Especially, the analogue 10s exhibited approximately potency with AZD5438 toward four cells including HeLa, HCT116, PC-3, and MDA-MB-231 with IC values of 0.

Short-term and long-term effects of PM on acute nasopharyngitis in 10 communities of Guangdong, China.

Objectives: We aimed to assess the effects of short-term and long-term exposure to ambient fine particle matter (PM) on acute nasopharyngitis.

Methods: A total of 9468 participants aged 18 years and above were recruited from 10 communities in four cities of Guangdong, China during the baseline survey in 2014, and they were followed-up from January 2015 to December 2016. Air pollution exposure was assessed based on the daily concentrations (short-term) and annual concentrations (long-term) of the nearby air monitoring station and the survey date.

Involvement of glutamate receptors in regulating calcium influx in rice seedlings under Cr exposure.

Glutamate receptors (GLRs) are ligand-gated Ca-permeable channels that govern and modulate the dynamic influx of cytosolic Ca in plants. The present study investigated the interaction of OsGLR3 gene expression with subcellular Ca distribution in rice seedlings exposed to chromium (Cr) solution containing Cr(III) or Cr(VI). The results displayed that the accumulation of Ca was evaluated or higher in shoots compared to roots under Cr exposure, and a similar pattern of subcellular Ca distribution was observed between rice tissues exposed to Cr(III) and Cr(VI).

Enhancing the performance of soil microbial fuel cells by using a bentonite-Fe and FeO modified anode.

To improve the performance of soil microbial fuel cells (SMFCs), FeO and bentonite-Fe were selected as anode modifiers, and correspondingly, graphite felt (GF), GF + FeO (GFF), and GF + bentonite-Fe (GFB) anodes were created and applied to the SMFCs system. The stable voltages of SMFCs were 249 mV for GFF and 324 mV for GFB, thus representing an increase by 8.26% (GFF) and 40.

Etiology of primary adrenal insufficiency in children: a 29-year single-center experience.

Background Primary adrenal insufficiency (PAI) in children is a rare condition and potentially lethal. The clinical characteristics are non-specific. It may be manifested as a chronic condition or crisis.

RICH2, a potential tumor suppressor in hepatocellular carcinoma.

Rho GTPase-activating proteins (RhoGAPs) are implicated in the development and progression of hepatocellular carcinoma (HCC). We tested the idea that RICH2 is a tumor suppressor in HCC. Consistent with this, RICH2 was downregulated in HCC and HCC cell lines and RICH2 expression negatively correlated with the tumor size, TNM stage and metastasis in HCC.

Biochemical characterization of Helicobacter pylori α1-3-fucosyltransferase and its application in the synthesis of fucosylated human milk oligosaccharides.

Fucosylated human milk oligosaccharides (HMOs) have important biological functions. Enzymatic synthesis of such compounds requires robust fucosyltransferases. A C-terminal 66-amino acid truncated version of Helicobacter pylori α1-3-fucosyltransferase (Hp3FT) is a good candidate.

Sequential Treatment of Cell Cycle Regulator and Nanoradiosensitizer Achieves Enhanced Radiotherapeutic Outcome.

Nanoradiosensitizers are promising agents for enhancing cancer radiotherapeutic efficiency. Although many attempts have been adopted to improve their radiation enhancement effect through regulation of their size, shape, and/or surface chemistry, few methods have achieved satisfactory radiotherapeutic outcomes. Herein, we propose a sequential drug treatment strategy through cell cycle regulation for achieving improved radiotherapeutic performance of the nanoradiosensitizers.

Changes in Serum Calcitonin Concentrations, Incidence of Medullary Thyroid Carcinoma, and Impact of Routine Calcitonin Concentration Monitoring in the EXenatide Study of Cardiovascular Event Lowering (EXSCEL).

Objective: Increases in serum calcitonin, a tumor marker for medullary thyroid carcinoma (MTC), have been associated with glucagon-like peptide 1 receptor agonist use in some preclinical studies. We report calcitonin changes in exenatide-treated and placebo-administered participants and MTC incidence in the EXenatide Study of Cardiovascular Event Lowering (EXSCEL) and consider the impact of within-trial calcitonin monitoring.

Research Design And Methods: EXSCEL participants were randomized 1:1 to once-weekly exenatide 2 mg or placebo.

Urinary Nephrin as a Biomarker of Glomerular Maturation and Injury Is Associated with Acute Kidney Injury and Mortality in Critically Ill Neonates.

Background: Nephrin is a key component of the slit diaphragm of the glomerular podocyte, and increased urinary nephrin level may reflect glomerular injury.

Objectives: To determine whether urinary nephrin is a useful biomarker of glomerular maturation and injury and whether it is associated with acute kidney injury (AKI) and neonatal intensive care unit (NICU) mortality in critically ill neonates.

Methods: Urinary samples were serially collected in 234 neonates during NICU stay for measurements of nephrin, cystatin C (CysC), and albumin.

Functional Characterization of a Cystathionine β-Synthase Gene in Sulfur Metabolism and Pathogenicity of Aspergillus niger in Pear Fruit.

Aspergillus niger, which is a fungal pathogen, causes rot in a variety of fruits. In this study, the cystathionine β-synthase cbsA gene was deleted by homologous recombination to study its role in sulfur metabolism and pathogenicity of A. niger.

Different Faces for Different Places: Heterogeneity of Neutrophil Phenotype and Function.

As the most abundant leukocytes in the circulation, neutrophils are committed to innate and adaptive immune effector function to protect the human body. They are capable of killing intruding microbes through various ways including phagocytosis, release of granules, and formation of extracellular traps. Recent research has revealed that neutrophils are heterogeneous in phenotype and function and can display outstanding plasticity in both homeostatic and disease states.

Noroleanane-type triterpenoids from L. and their anti-α-glucosidase activities.

Falcatane A () and B (), 4-oxo-3,24-dinor-2,4-secooleanane- and 3-oxo-24- noroleanane-type triterpenoids, together with seven known triterpenoids involving 2-hydroxy-3-oxo-24-noroleana-1,4,12-trien-28-oic acid () and oleanolic acid (), were separated from the ethyl acetate roots extract of using the column chromatography of silica gel, MCI gel, and Sephadex LH-20. The compounds were determined by analysis of IR, NMR spectroscopic data and mass spectrometry. In the bioassay, all isolates showed varying degree of the α-glucosidase inhibitory activity except compound .

MiR-291a/b-5p inhibits autophagy by targeting Atg5 and Becn1 during mouse preimplantation embryo development.

microRNA-290 (miR-290) clusters are highly expressed in mouse preimplantation embryos, but their specific role and regulatory mechanisms in the development of mouse preimplantation embryos remain unclear. Here, we found that miR-291a-5p and miR-291b-5p, as mature microRNA molecules of miR-290 clusters, were dynamically expressed in mouse preimplantation embryos. The expression of miR-291a-5p and miR-291b-5p in mouse embryos increased during the 2-4-cell stages and was accompanied by the decreasing expression of the autophagy-related genes Atg5 and Becn1 in mRNA.