Regio-specific enzymatic glucosylation of triterpenoids from Antrodia camphorata and their biological activities.

The bacterial glycosyltransferase YjiC1 was used to glycosylate triterpenoids from the medicinal fungus Antrodia camphorata. Eleven new compounds were obtained from enzymatic reactions. Glucosylation could increase the inhibitory activities against COX-2, and improve the anti-inflammatory activities of Antrodia ergostanes on acute lung injury mice, especially (25R)-antcin C 7-O-ß-D-glucoside.

Structure and Physical Properties of the Layered Titanium-Based Pnictide Oxides (EuF)2Ti2Pn2O (Pn = Sb, Bi).

We report two novel titanium-based pnictide oxide compounds (EuF)2Ti2Pn2O (Pn = Sb, Bi), which are synthesized by replacing Sr2+ in (SrF)2Ti2Pn2O [Liu, R. H. Structure and Physical Properties of the Layered Pnictide-Oxides: (SrF)2Ti2Pn2O (Pn = As, Sb) and (SmO)2Ti2Sb2O. Chem. Mater. 2010, 22, 1503-1508] with Eu2+ using a solid-state reaction. (EuF)2Ti2Sb2O exhibits an obvious anomaly in resistivity and heat capacity at T ∼ 195 K, which may arise from the spin-density wave/charge-density wave instability. Similar features are also observed in BaTi2Pn2O, (SrF)2Ti2Pn2O, and Na2Ti2Pn2O (Pn = As and Sb) [Liu, R. H. Structure and Physical Properties of the Layered Pnictide-Oxides: (SrF)2Ti2Pn2O (Pn = As, Sb) and (SmO)2Ti2Sb2O. Chem. Mater. 2010, 22, 1503-1508, Ozawa, T. C. Chemistry of layered d-metal pnictide oxides and their potential as candidates for new superconductors. Sci. Technol. Adv. Mater. 2008, 9, 033003, Wang, X. F. Structure and physical properties for a new layered pnictide-oxide: BaTi2As2O. J. Phys.: Condens. Matter. 2010, 22, 075702, and Xu, H. C. Electronic structure of the BaTi2As2O parent compound of the titanium-based oxypnictide superconductor. Phys. Rev. B 2014, 89, 155108]. Magnetic susceptibility measurements indicate an antiferromagnetic transition at T ∼ 2.5 K for (EuF)2Ti2Sb2O. In particular, the electronic specific heat coefficients of both (EuF)2Ti2Sb2O and (EuF)2Ti2Bi2O are significantly enhanced compared to those of (SrF)2Ti2Pn2O, Na2Ti2Pn2O, and BaTi2Pn2O,1,5,6 which may be due to a strong electron correlation effect in this system. Thus, (EuF)2Ti2Pn2O (Pn = Sb, Bi) may provide new platforms for studying density wave, magnetic ordering, and electron correlation effects.

Constructing van der Waals heterostructures by dry-transfer assembly for novel optoelectronic device.

Since the first successful exfoliation of graphene, the superior physical and chemical properties of two-dimensional (2D) materials, such as atomic thickness, strong in-plane bonding energy and weak inter-layer van der Waals (vdW) force have attracted wide attention. Meanwhile, there is a surge of interest in novel physics which is absent in bulk materials. Thus, vertical stacking of 2D materials could be critical to discover such physics and develop novel optoelectronic applications. Although vdW heterostructures have been grown by chemical vapor deposition, the available choices of materials for stacking is limited and the device yield is yet to be improved. Another approach to build vdW heterostructure relies on wet/dry transfer techniques like stacking Lego bricks. Although previous reviews have surveyed various wet transfer techniques, novel dry transfer techniques have been recently been demonstrated, featuring clean and sharp interfaces, which also gets rid of contamination, wrinkles, bubbles formed during wet transfer. This review summarizes the optimized dry transfer methods, which paves the way towards high-quality 2D material heterostructures with optimized interfaces. Such transfer techniques also lead to new physical phenomena while enable novel optoelectronic applications on artificial vdW heterostructures, which are discussed in the last part of this review.

Difficulties and countermeasures in implementing age-friendly policies in primary health centers in Taiwan.

BACKGROUND: Taiwan is predicted to become a super-aged society by 2025, and primary health centers (PHCs) are set to play a crucial role in the care of older adults. The Taiwanese government has developed an age-friendly verification framework for PHC. The aims of this study were to explore the difficulties faced by PHC staff in the implementation of age-friendly policies and their solution strategies. METHODS: This study adopted a qualitative research method. The first stage involved conducting five focus groups with the responsible staff of PHCs (n = 41) that have been certified "age-friendly." The focus groups covered the effectiveness, difficulties, and resources of PHCs in regards to the introduction of age-friendly policies. In the second stage, in-depth interviews were conducted with executives of PHCs (n = 5), both certified and not certified as age-friendly, to further compare the difficulties faced by these two types of PHCs, thereby gaining perspectives for solution strategies. The principles of grounded theory were used for data analysis. RESULTS: Four major PHC strategies are employed in the promotion of age-friendliness. First, organizational management, through which managers apply management methods and analyze the present PHC-related health concerns; second, resource utilization, which refers to the tallying, linking, and integrating of resources; third, business operation process, in which work efficiency is improved through the combination of business operations and staff training; finally, hardware improvement, which is achieved through comprehensive cataloging of facility environments. CONCLUSION: The implementation of age-friendliness in PHCs requires the efforts of both the service units and government. With resources provided by the government, PHCs can integrate management methods, businesses operations, and essential resources. Moreover, PHC executives can lead their teams in promoting age-friendly policies, and closely monitor their effectiveness.

Functional Characterization and Protein Engineering of a Triterpene 3-/6-/2'-O-Glycosyltransferase Reveal a Conserved Residue Critical for the Regiospecificity.

Engineering the function of triterpene glucosyltransferases (GTs) is challenging due to the large size of the sugar acceptors. In this work, we identified a multifunctional glycosyltransferase AmGT8 catalyzing triterpene 3-/6-/2'-O-glycosylation from the medicinal plant Astragalus membranaceus. To engineer its regiospecificity, a small mutant library was built based on semi-rational design. Variants A394F, A394D, and T131V were found to catalyze specific 6-O, 3-O, and 2'-O glycosylation, respectively. The origin of regioselectivity of AmGT8 and its A394F variant was studied by molecular dynamics and hydrogen deuterium exchange mass spectrometry. Residue 394 is highly conserved as A/G and is critical for the regiospecificity of the C- and O-GTs TcCGT1 and GuGT10/14. Finally, astragalosides III and IV were synthesized by mutants A394F, T131V and P192E. This work reports biocatalysts for saponin synthesis and gives new insights into protein engineering of regioselectivity in plant GTs.

Phytochemistry and cardiovascular protective effects of Huang-Qi (Astragali Radix).

Huang-Qi (Astragali Radix) is an herbal tonic widely used in China and many other countries. It is derived from the roots of Astragalus membranaceus and A. membranaceus var. mongholicus and shows potent cardiovascular protective effects. In this article, we comprehensively reviewed 189 small molecules isolated from the two Astragalus species and discussed the interspecies chemical differences. Moreover, we summarized the pharmacological activities and mechanisms of action of Huang-Qi and its major bioactive compounds for the treatment of cardiovascular diseases. This review covers 171 references published between February 1983 and March 2020.

In Situ Observation of Low-Power Nano-Synaptic Response in Graphene Oxide Using Conductive Atomic Force Microscopy.

Multiple studies have reported the observation of electro-synaptic response in different metal/insulator/metal devices. However, most of them analyzed large (>1 µm2 ) devices that do not meet the integration density required by industry (1010  devices/mm2 ). Some studies emploied a scanning tunneling microscope (STM) to explore nano-synaptic response in different materials, but in this setup there is a nanogap between the insulator and one of the metallic electrodes (i.e., the STM tip), not present in real devices. Here, it is demonstrated how to use conductive atomic force microscopy to explore the presence and quality of nano-synaptic response in confined areas <50 nm2 . Graphene oxide (GO) is selected due to its easy fabrication. Metal/GO/metal nano-synapses exhibit potentiation and paired pulse facilitation with low write current levels <1 µA (i.e., power consumption ≈3 µW), controllable excitatory post-synaptic currents, and long-term potentiation and depression. The results provide a new method to explore nano-synaptic plasticity at the nanoscale, and point to GO as an important candidate for the fabrication of ultrasmall (<50 nm2 ) electronic synapses fulfilling the integration density requirements of neuromorphic systems.

Consideration factors of older adults seeking medical treatment at outpatient services in Taiwan.

BACKGROUND: Taiwan will become a super-aged society by 2025, leading to the more frequent use of outpatient services by older adults for medical treatment compared with other age groups. Understanding the outpatient service consideration factors of older adults seeking medical treatment can improve health care quality. This study explored the selection factors and crucial considerations of older adults for outpatient services. METHODS: Qualitative study was conducted. Purposive sampling was used to recruit 16 older adults over 65 years of age with chronic disease who were patients of an internal medicine department and regularly returned for checkups. Data including reasons for receiving medical treatment, factors affecting their choice of hospitals, and health care and environmental considerations were collected through structured interviews. RESULTS: The older adults identified four factors. (1) The care of doctors: The doctors possessed professional skill, allocate sufficient consultation time, and undertake effective communication. (2) The care of other medical professionals: Other medical professionals provided services in a cordial manner. (3) The accessibility and convenience of outpatient services: Convenient transportation and registration as well as short consultation wait time. (4) Environment and equipment: The hospital had the novel facilities and satisfactory barrier-free equipment. CONCLUSIONS: The older adults cared most about the adequacy of diagnosis and treatment by doctors and other medical professionals. In addition, they reported having higher satisfaction with hospitals that provide comprehensive medical facilities, fast and convenient medical procedures, and short wait times.

Functional Characterization and Structural Basis of an Efficient Di-C-glycosyltransferase from Glycyrrhiza glabra.

A highly efficient di-C-glycosyltransferase GgCGT was discovered from the medicinal plant Glycyrrhiza glabra. GgCGT catalyzes a two-step di-C-glycosylation of flopropione-containing substrates with conversion rates of >98%. To elucidate the catalytic mechanisms of GgCGT, we solved its crystal structures in complex with UDP-Glc, UDP-Gal, UDP/phloretin, and UDP/nothofagin, respectively. Structural analysis revealed that the sugar donor selectivity was controlled by the hydrogen-bond interactions of sugar hydroxyl groups with D390 and other key residues. The di-C-glycosylation capability of GgCGT was attributed to a spacious substrate-binding tunnel, and the G389K mutation could switch di- to mono-C-glycosylation. GgCGT is the first di-C-glycosyltransferase with a crystal structure, and the first C-glycosyltransferase with a complex structure containing a sugar acceptor. This work could benefit the development of efficient biocatalysts to synthesize C-glycosides with medicinal potential.

Plasma levels of Interleukin 18 but not amyloid-ß or Tau are elevated in female depressive patients.

BACKGROUND: Depression is associated with inflammation and Alzheimer's disease (AD). However, detailed molecular mechanisms linking mood, neuroinflammation and AD remain unclear. Although changes in peripheral inflammatory factors such as Interleukin 18 (IL18), and AD-associated amyloid-ß (Aß) peptides have been linked to depression, a solid relationship between these factors in depressive disorder has yet to be established. This study aims to further determine whether plasma IL18, Aß40, Aß42, and the AD-associated tangle component Tau, as well as IL18 single nucleotide polymorphisms (SNPs) may be biomarkers for depression. METHODS: We measured plasma IL18, Aß40, Aß42, and Tau in 64 depressive patients and 75 healthy controls, and characterized genotypes of three IL18 SNPs (rs187238, rs1946518 and rs1946519) in these subjects. Comparisons between depressive patients and controls were carried out in males, in females or in combination. Regression analyses were conducted to examine the correlation between these parameters. RESULTS: We found that none of the plasma levels of IL18, Aß40, Aß42, and Tau, the ratio of Aß42/Aß40, and the genotypes of IL18 SNPs were significantly different between combined depressive patients and combined healthy controls, or between male depressive patients and male controls. However, IL18 levels were less in females than in males in healthy people and were significantly increased in female depressive patients compared to female controls. Moreover, IL18 and standardized IL18 were correlated with standardized Aß42/Aß40 ratio and standardized Tau in depressive patients. CONCLUSIONS: Plasma IL18 may be a potential biomarker for depression in women.

Distinguishing Oxygen Vacancy Electromigration and Conductive Filament Formation in TiO2 Resistance Switching Using Liquid Electrolyte Contacts.

Resistance switching in TiO2 and many other transition metal oxide resistive random access memory materials is believed to involve the assembly and breaking of interacting oxygen vacancy filaments via the combined effects of field-driven ion migration and local electronic conduction leading to Joule heating. These complex processes are very difficult to study directly in part because the filaments form between metallic electrode layers that block their observation by most characterization techniques. By replacing the top electrode layer in a metal-insulator-metal memory structure with easily removable liquid electrolytes, either an ionic liquid (IL) with high resistance contact or a conductive aqueous electrolyte, we probe field-driven oxygen vacancy redistribution in TiO2 thin films under conditions that either suppress or promote Joule heating. Oxygen isotope exchange experiments indicate that exchange of oxygen ions between TiO2 and the IL is facile at room temperature. Oxygen loss significantly increases the conductivity of the TiO2 films; however, filament formation is not observed after IL gating alone. Replacing the IL with a more conductive aqueous electrolyte contact and biasing does produce electroformed conductive filaments, consistent with a requirement for Joule heating to enhance the vacancy concentration and mobility at specific locations in the film.

A facile method for the synthesis of 2-(3-hydroxy-1-adamantyl)-2-oxoacetic acid and it's optimization.

2-(3-hydroxy-1-adamantyl)-2-oxoacetic acid (IV), a key intermediate of saxagliptin for type 2 diabetes mellitus (T2DM), was prepared from 1-adamantanecarboxylic acid(I) via oxidation by potassium permanganate(KMnO4) to afford 3-hydroxy-1-adamantanecarboxylic acid (II), which was treated with a one-pot method to give 1-acetyl-3-hydroxyadamantane (III) followed by oxidation. Some key steps were optimized and the overall yield was about 51%.

Body fluid levels of neuroactive amino acids in autism spectrum disorders: a review of the literature.

A review of studies on the body fluid levels of neuroactive amino acids, including glutamate, glutamine, taurine, gamma-aminobutyric acid (GABA), glycine, tryptophan, D-serine, and others, in autism spectrum disorders (ASD) is given. The results reported in the literature are generally inconclusive and contradictory, but there has been considerable variation among the previous studies in terms of factors such as age, gender, number of subjects, intelligence quotient, and psychoactive medication being taken. Future studies should include simultaneous analyses of a large number of amino acids [including D-serine and branched-chain amino acids (BCAAs)] and standardization of the factors mentioned above. It may also be appropriate to use saliva sampling to detect amino acids in ASD patients in the future-this is noninvasive testing that can be done easily more frequently than other sampling, thus providing more dynamic monitoring.

A New ZrCuSiAs-Type Superconductor: ThFeAsN.

We report the first nitrogen-containing iron-pnictide superconductor ThFeAsN, which is synthesized by a solid-state reaction in an evacuated container. The compound crystallizes in a ZrCuSiAs-type structure with the space group P4/nmm and lattice parameters a = 4.0367(1) Å and c = 8.5262(2) Å at 300 K. The electrical resistivity and dc magnetic susceptibility measurements indicate superconductivity at 30 K for the nominally undoped ThFeAsN.

Low-dose Infliximab for Induction and Maintenance Treatment in Chinese Patients With Moderate to Severe Active Ulcerative Colitis.

GOAL: To evaluate the efficacy of low-dose (3.5 mg/kg) infliximab for induction and maintenance treatment in Chinese patients with ulcerative colitis. BACKGROUND: Treatment with 4 to 5 mg/kg of infliximab also proved to be effective in treating moderate to severe ulcerative colitis. At present there is no relevant study on the effectiveness of infliximab doses lower than 4 mg/kg in patients with ulcerative colitis. STUDY: A prospective, randomized, double-blind, placebo-controlled, and single-centered study was designed. A total of 123 patients (from 17 provinces of China) with moderate to severe active ulcerative colitis despite treatment with concurrent drugs received placebo or low-dose (3.5 mg/kg) or standard-dose (5 mg/kg) infliximab intravenously at weeks 0, 2, and 6 and then every 8 weeks through week 22. Patients were followed up for 30 weeks. RESULTS: Overall, 73% and 78% of patients who received low-dose (3.5 mg/kg) and standard-dose (5 mg/kg) infliximab, respectively, had clinical responses at week 8, as compared with 37% of patients who received placebo (P<0.01 for both comparisons with placebo). The number of patients who received low-dose (3.5 mg/kg) or standard-dose (5 mg/kg) infliximab with a clinical response at week 30 (63% and 66%, respectively) was more than the patients who received placebo (27%, P<0.01 for both comparisons). CONCLUSIONS: Chinese patients with moderate to severe active ulcerative colitis treated with low-dose (3.5 mg/kg) or standard-dose (5 mg/kg) infliximab at weeks 0, 2, and 6 and every 8 weeks thereafter were more likely to have a clinical response at weeks 8 and 30 than those who received placebo.

Combined diosmectite and mesalazine treatment for mild-to-moderate ulcerative colitis: a randomized, placebo-controlled study.

BACKGROUND: The relapse rate of ulcerative colitis (UC) is high. The efficacy of combined diosmectite and mesalazine treatment for active mild-to-moderate UC was investigated. MATERIAL/METHODS: A total of 120 patients with UC were enrolled in this randomized, single-blind, placebo-controlled study. Sixty patients were assigned to the Diosmectite group (diosmectite and mesalazine) and 60 were assigned to Placebo group (placebo and mesalazine). In the induction phase, the primary end point was the clinical remission rate at 8 weeks; secondary end points were clinical response, endothelial mucosal healing, Mayo score, erythrocyte sedimentation rate, C-reactive protein levels, and defecation frequency. In the maintenance phase, the primary end point was clinical remission at 52 weeks; secondary end points were clinical response, endothelial mucosal healing, Mayo score, erythrocyte sedimentation rate, and defecation frequency. RESULTS: At 8 weeks, the Diosmectite group had a significantly higher clinical remission rate (68.3% vs. 50%) and mucosal healing rate (66.7% vs. 48.3%) compared with the Placebo group. There were no significant differences in clinical response rates, Mayo score, erythrocyte sedimentation rate, C-reactive protein, or defecation frequency. At 52 weeks, the Diosmectite group had a significantly higher clinical remission rate (61.7% vs. 40%) and mucosal healing rate (60% vs. 38.3%) compared with the Placebo group. Defecation frequency was lower, but this was not significant. CONCLUSIONS: Combined diosmectite and mesalazine treatment successfully induced and maintained the treatment of active mild-to-moderate UC as indicated by higher rates of clinical remission and mucosal healing.

Anomalous Eu valence state and superconductivity in undoped Eu3Bi2S4F4.

We have synthesized a novel europium bismuth sulfofluoride, Eu3Bi2S4F4, by solid-state reactions in sealed evacuated quartz ampules. The compound crystallizes in a tetragonal lattice (space group I4/mmm, a = 4.0771(1) Å, c = 32.4330(6) Å, and Z = 2), in which CaF2-type Eu3F4 layers and NaCl-like BiS2 bilayers stack alternately along the crystallographic c axis. There are two crystallographically distinct Eu sites, Eu(1) and Eu(2) at the Wyckoff positions 4e and 2a, respectively. Our bond valence sum calculation, based on the refined structural data, indicates that Eu(1) is essentially divalent, while Eu(2) has an average valence of ∼ +2.64(5). This anomalous Eu valence state is further confirmed and supported, respectively, by Mössbauer and magnetization measurements. The Eu(3+) components donate electrons into the conduction bands that are mainly composed of Bi 6px and 6py states. Consequently, the material itself shows metallic conduction and superconducts at 1.5 K without extrinsic chemical doping.

Design and synthesis of a new layered thermoelectric material LaPbBiS3O.

A new quinary oxysulfide LaPbBiS3O was designed and successfully synthesized via a solid-state reaction in a sealed evacuated quartz tube. This material, composed of stacked NaCl-like [M4S6] (where M = Pb, Bi) layers and fluorite-type [La2O2] layers, crystallizes in the tetragonal space group P4/nmm with a = 4.0982(1) Å, c = 19.7754(6) Å, and Z = 2. Electrical resistivity and Hall effect measurements demonstrate that it is a narrow gap semiconductor with an activation energy of ∼17 meV. The thermopower and the figure of merit at room temperature were measured to be -52 µV/K and 0.23, respectively, which makes LaPbBiS3O and its derivatives be promising for thermoelectric applications.

[Microbubbles targeted to P-selectin for evaluating testicular ischemia-reperfusion injury in rabbits].

OBJECTIVE: To explore the feasibility of evaluating complete ischemia-reperfusion injury (IRI) of the testis by contrast-enhanced ultrasonography with microbubbles (MB) targeted to P-selectin (MBp) in rabbits. METHODS: We randomly divided 30 healthy adult rabbits into five groups of equal number (control, 0.5 h IRI, 1 h IRI, 2 h IRI, and 4 h IRI), prepared phospholipid MB and MBp, and performed contrast-enhanced ultrasonography of the bilateral testes with MB or MBp at an interval of 20 min at different times after IRI. When MB or MBp disappeared completely in the healthy testis at 4 to 5 min after intravenous injection, we recorded the power of the first frame (F-P) in the IRI testes followed by immunohistochemical staining of the testis tissue. RESULTS: CEU with MBp achieved a significantly higher F-P than that with MB in all the IRI groups (P < 0.05), which was (8.34 +/- 1.20) versus (1.87 +/- 0.25) 10(-5) AU at 2 hours, but there was no significant difference between MB and MBp in the control rabbits (0 AU, P > 0.05). Immunohistochemistry showed a significantly time-dependent increase in the expression of P-selectin in the vascular endothelial cells of the IRI testes, but not in those of the control. CONCLUSION: Contrast-enhanced ultrasonography with MBp can be used to evaluate the inflammatory reaction of testicular ischemia-reperfusion injury.

ILC2s: Unraveling the innate immune orchestrators in allergic inflammation.

The prevalence rate of allergic diseases including asthma, atopic rhinitis (AR) and atopic dermatitis (AD) has been significantly increasing in recent decades due to environmental changes and social developments. With the study of innate lymphoid cells, the crucial role played by type 2 innate lymphoid cells (ILC2s) have been progressively unveiled in allergic diseases. ILC2s, which are a subset of innate lymphocytes initiate allergic responses. They respond swiftly during the onset of allergic reactions and produce type 2 cytokines, working in conjunction with T helper type 2 (Th2) cells to induce and sustain type 2 immune responses. The role of ILC2s represents an intriguing frontier in immunology; however, the intricate immune mechanisms of ILC2s in allergic responses remain relatively poorly understood. To gain a comphrehensive understanding of the research progress of ILC2, we summarize recent advances in ILC2s biology in pathologic allergic inflammation to inspire novel approaches for managing allergic diseases.