Highly efficient catalytic oxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid using bimetallic Pt-Cu alloy nanoparticles as catalysts.

Bimetallic platinum-copper alloy nanoparticles are highly active catalysts for the oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) under base-free conditions, with a high turnover frequency of up to 135 h-1 in aqueous solution. The Pt-Cu1.5/AC alloyed catalyst promoted the rate-determining step in the tandem oxidation compared with the monometallic Pt/AC catalyst, thus improving the catalytic performance.

Crystal-phase engineering of PdCu nanoalloys facilitates selective hydrodeoxygenation at room temperature.

Selective hydrodeoxygenation of biomass-derived aromatic alcohols to value-added chemical or fuel is of great importance for sustainable biomass upgrading, and hydrodeoxygenation of 5-hydroxymethylfurfural (HMF) to 2,5-dimethylfuran (DMF) is one of the most attractive reactions. Achieving the conversion of HMF to DMF using H2 at ambient temperature is challenging. In this work, we used PdCu nanoalloys to catalyze the selective hydrodeoxygenation reaction of HMF to DMF using H2 as the reducing agent. The reaction path and the product selectivity are governed by the crystallographic phase of the PdCu nanoalloys. It was discovered that body-centered cubic (BCC) PdCu nanoalloys supported on activated carbon (AC) exhibited outstanding performance with 93.6% yield of DMF at room temperature (PdCu/AC-BCC). A combination of experimental and density functional theory (DFT) studies showed that the tilted adsorption modes of furanic intermediates on PdCu-BCC nanoalloy surfaces accounted for the high selectivity of DMF; however, furan ring was activated on PdCu face-centered cubic (FCC) nanoalloy surfaces. Furthermore, PdCu/AC-BCC could also catalyze the hydrodeoxygenation of other aromatic alcohols at room temperature while maintaining the aromatic structures. This work opens the way for selective hydrodeoxygenation of the aromatic alcohols at room temperature with the aromatic ring intact.

Organic amine mediated cleavage of Caromatic-Cα bonds in lignin and its platform molecules.

The activation and cleavage of C-C bonds remains a critical scientific issue in many organic reactions and is an unmet challenge due to their intrinsic inertness and ubiquity. Meanwhile, it is crucial for the valorization of lignin into high-value chemicals. Here, we proposed a novel strategy to enhance the Caromatic-Cα bond cleavage by pre-functionalization with amine sources, in which an active amine intermediate is first formed through Markovnikov hydroamination to reduce the dissociation energy of the Caromatic-Cα bond which is then cleaved to form target chemicals. More importantly, this strategy provides a method to achieve the maximum utilization of the aromatic nucleus and side chains in lignin or its platform molecules. Phenols and N,N-dimethylethylamine compounds with high yields were produced from herbaceous lignin or the p-coumaric acid monomer in the presence of industrially available dimethylamine (DMA).

Copper/Carbon Heterogenous Interfaces for Enhanced Selective Electrocatalytic Reduction of CO2 to Formate.

Electrochemical reduction of CO2 (CO2 RR) to formate is a promising route to prepare value-added chemical. Developing low-cost and efficient electrocatalysts with high product selectivity is still a grand challenge. Herein, a novel Cu anchored on hollow carbon spheres catalysts (HCS/Cu-x, x represents the mass of CuCl2 added in the system) is designed with controllable copper/carbon heterogenous interfaces. Rich copper/carbon heterogenous interfaces and hollow structure of optimized HCS/Cu-0.12 catalyst are beneficial to charge transmission. Compared with the CO2 RR occurred in aqueous electrolyte over Cu-based catalyst that has been reported to date, it exhibits highest formate Faradaic efficiency (FE) of 82.4% with a current density of 26 mA cm-2 and remarkable stability in a H-cell.

Production of Piperidine and δ-Lactam Chemicals from Biomass-Derived Triacetic Acid Lactone.

Piperidine and δ-Lactam chemicals have wide application, which are currently produced from fossil resource in industry. Production of this kind of chemicals from lignocellulosic biomass is of great importance, but is challenging and the reported routes give low yield. Herein, we demonstrate the strategy to synthesize 2-methyl piperidine (MP) and 6-methylpiperidin-2-one (MPO) from biomass-derived triacetic acid lactone (TAL) that is produced microbially from glucose. In this route, TAL was firstly converted into 4-hydroxy-6-methylpyridin-2(1H)-one (HMPO) through facile aminolysis, subsequently HMPO was selectively transformed into MP or MPO over Ru catalysts supported on beta zeolite (Ru/BEA-X, X is the molar ratio of Si to Al) via the tandem reaction. It was found that the yield of MP could reach 76.5 % over Ru/BEA-60 in t-BuOH, and the yield of MPO could be 78.5 % in dioxane. Systematic studies reveal that the excellent catalytic performance of Ru/BEA-60 was closely correlated with the cooperative effects between active metal and acidic zeolite with large pore geometries. The related reaction pathway was studied on the basis of control experiments.

Selective hydrogenation of 5-(hydroxymethyl)furfural to 5-methylfurfural over single atomic metals anchored on Nb2O5.

5-Methylfurfural (MF) is a very useful chemical. Selective hydrogenation of biomass platform molecule 5-(hydroxymethyl)furfural (HMF) to MF using H2 as the reducing agent is very attractive, but challenging because hydrogenation of C=O bond in HMF is more favourable than C-OH both kinetically and thermodynamically, and this route has not been realized. In this work, we prepare isolated single atomic catalysts (SACs) Pt1/Nb2O5-Ov, Pd1/Nb2O5-Ov, and Au1/Nb2O5-Ov, in which single metal atoms are supported on oxygen defective Nb2O5 (Nb2O5-Ov). It is discovered that the SACs can efficiently catalyze the hydrogenation of HMF to MF using H2 as the reducing agent with MF selectivity of >99% at complete conversion, while the selectivities of the metal nanocatalysts supported on Nb2O5 are very poor. A combination of experimental and density function theory (DFT) studies show that the unique features of the SACs for the reaction result from the cooperation of the Nb and Pt sites near the interface in the Pt1/Nb2O5-Ov. The Pt atoms are responsible for the activation of H2 and the Nb sites activate C-OH in the reaction. This work opens the way for producing MF by direct hydrogenation of biomass-derived HMF using H2 as the reductant.

MicroRNA-1297 contributes to the progression of human cervical carcinoma through PTEN.

BACKGROUND: The human cervical carcinoma oncogenic mechanisms still remain elusive. Thus, we proposed to understand the biological role of a newly discovered therapeutic miRNA. METHODS: MiR-1297 related to human cervical carcinoma was selected for this study. TaqMan qRT- PCR assay was used to profile miRNA, phosphatase and tensin homolog (PTEN) expression in randomly chosen tumour with non-tumour tissues, and the apoptosis factors expression. Cell proliferation was monitored by CCK-8 assay and colony formation assay. Apoptosis was determined by flow cytometry. Protein level was determined by western blotting. 3'UTR was performed to validate the direct binding sites of miR-1297 on PTEN. SPSS was used for statistical analyses. RESULTS: MiR-1297 is repressed and PTEN activated in human cervical cancer tissues. After miR-1297 overexpression, HeLa cells had an increase in cell proliferation and decrease in apoptosis. PTEN expression is negatively correlation with miR-1297. PTEN silencing display the similar pattern as miRNA-1297 overexpression to inhibit HeLa cell growth and apoptosis in vitro. CONCLUSIONS: Our data indicate that miR-1297 contribute to the human cervical carcinoma through PTEN. miR-1297 could be a reasonable miRNA for future studies.

Effects of letrozole in combination with low-dose intramuscular injection of human menopausal gonadotropin on ovulation and pregnancy of 156 patients with polycystic ovary syndrome.

OBJECTIVE: To explore the effects of letrozole (LE) in combination with low-dose intramuscular injection of human menopausal gonadotropin (HMG) on the ovulation induction and pregnancy of patients with polycystic ovary syndrome (PCOS). METHODS: A total of 156 patients with PCOS infertility were randomly divided into an LE group, a clomiphene citrate (CC) group and an LE + HMG group (n= 52). LE and CC were orally taken according to the prescribed dosage on the 3rd-5th days of menstruation respectively, and 75 IU HMG was given through intramuscular injection. The ovulation induction parameters and pregnancy outcomes were observed. RESULTS: The number of ovulation cycle of LE + HMG group was significantly higher than that of LE group (χ2=8.451, P<0.001). After injection of human chorionic gonadotropin, both endometrial thickness and number of mature follicles of LE + HMG group were significantly higher than those of other two groups (P<0.001), and the daily estradiol (E2) level was also higher (q=4.531, P<0.05). The pregnancy rate of LE + HMG group was 55.7%, which exceeded those of other two groups (compared to LE group, χ2=4.012, P<0.05). In LE + HMG group, the average medication cycle of clinically pregnant patients was (2.9 ± 0.3) weeks, which was significantly shorter than those of CC and LE groups (F=17.241, P<0.001). CONCLUSION: The regimen using LE in combination with low-dose intramuscular injection of HMG has satisfactory therapeutic effects on ovulation induction, short medication cycle and high clinical pregnancy rate, which is promising for treating patients with PCOS infertility.

Structure-function analysis of DNA helicase HELQ: A new diagnostic marker in ovarian cancer.

It has been previously reported that a deficiency of the helicase, POLQ-like (HELQ) gene increases the risk of ovarian cancer. The present study aimed to explore the structure-function association of HELQ and discuss the effect of molecular structure on the occurrence of tumors. ExPASy tools were employed to analyze the physicochemical properties and secondary structure of the genes. PHYRE2 Protein Fold Recognition Server was used to construct the three-dimensional model and find the ligand-binding sites of HELQ. In addition, the potential functions corresponding to these structures were excavated by comparing and analyzing protein domains. The HELQ protein is located in the cytoplasm (56.5%) and nucleus (21.7%). HELQ has 4 conserved domains, consisting of DEXDc, HELICc, HHH_5 and PRK02362, which contain the adenosine triphosphate (ATP) binding site, nucleotide binding region and putative Mg2+ binding site. In the secondary structure, it was found that HELQ was mainly composed of α helix (46.68%) and random coils (43.05%), with only 10.26% extended strand. According to 3DLigandSite Server, the ligand binding sites appeared in ILE333, LYS335, TYR337, SER362, LEU367, LYS397, GLN340, GLY363, GLY364 and ASN678 of the amino acid sequence. Among the functional protein association networks, regulator of telomere elongation helicase 1, family with sequence similarity 175 member A, small ubiquitin-like modifier 1, DNA polymerase ν and coiled-coil domain containing 158 were involved and co-expressed with HELQ. PredictProtein analysis indicated that the dominant functions of HELQ were ATP-dependent helicase activity and participation in the DNA repair process. Characteristics of the HELQ protein were obtained by bioinformatics analysis, based on which the role of HELQ in DNA replication, DNA repair and maintenance of genomic stability was explored. It was concluded that modulation the function of HELQ helicase may be used in the treatment of ovarian cancer.

[Effect of the treatment acceptance on the perinatal outcomes in women with subclinical hypothyroidism, positive thyroid gland peroxidase antibody in early pregnancy].

OBJECTIVE: To investigate if women with subclinical hypothyroidism (SCH), positive thyroid gland peroxidase antibody (TPOAb) in early pregnancy accepted treatment or not had effect on perinatal outcomes. METHODS: 15 000 pregnant women who delivered in Women and Infants Hospital of Zhengzhou from January 1, 2013 to June 30, 2014 were recruited retrospectively. Among them, 2 042 women had SCH in early pregnancy. The diagnostic standard of SCH was serum free thyroxine (FT4) between 12.91-22.35 pmol/L and TSH level between 5.22-10.00 mU/L. TPOAb level ≥ 34 U/L was defined as positive result. The 2 042 patients with SCH were divided into the treated group (1 236 cases) and the untreated group (806 cases), according to whether or not women accepted the levothyroxine treatment. Meanwhile, the 2 042 patients with SCH were divided into the TPOAb (+) treated group (1 021 cases), the TPOAb (+) untreated group (201 cases), the TPOAb (-) treated group (215 cases) and the TPOAb (-) untreated group (605 cases), according to the TPOAb result and acceptance the levothyroxine treatment. 2 000 pregnant women with normal thyroid function who delivered in the same period were selected as the control group. Perinatal outcomes were analyzed. RESULTS: (1) The incidence of SCH in early pregnancy was 13.61% (2 042/15 000). 60.53% (1 236/2 042) accepted levothyroxine treatment and 39.47% (806/2 042) did not. (2) The incidence of abortion (5.71%, 46/806), premature delivery (6.20%, 50/806), gestational hypertension disease (13.90%, 112/806), gestational diabetes mellitus (GDM; 6.58%, 53/806), fetal growth restriction (FGR; 12.28%, 99/806) and low birth weight infants (10.17%, 82/806) in the untreated group were higher than those in the treated group [3.96% (49/1 236), 4.21% (52/1 236), 10.76% (133/1 236), 4.13% (51/1 236), 8.90% (110/1 236), 7.52% (93/1 236), respectively] and the control group [3.60% (72/2 000), 4.00% (80/2 000), 10.70% (214/2 000), 3.80% (76/2 000), 9.60% (192/2 000), 7.50% (150/2 000), respectively]. The differences were statistically significant (P < 0.05). While there was no statistically significant difference in the incidence of placental abruption, anemia in pregnant women, or fetal distress among the three groups (P > 0.05). (3)The incidences of abortion (11.44%, 23/201), premature delivery (12.44%, 25/201), gestational hypertension disease (22.89%, 46/201), GDM (8.46%, 17/201), FGR (19.90%, 40/201) and low birth weight infants (16.42%, 33/201) in the TPOAb (+) untreated group were higher than those in TPOAb (+) treated group [4.02% (41/1 021), 4.21% (43/1 021), 10.77% (110/1 021), 4.11% (42/1 021), 8.72% (89/1 021), 7.35% (75/1 021), respectively] and the control group, with statistically significant differences (P < 0.05). The incidence of the pregnancy complications in the TPOAb (+) treated group was higher than those in the control group, but the differences were not statistically significant (P > 0.05). (4) There were no statistically significant difference (P > 0.05) in the incidence of abortion (3.72%, 8/215), premature delivery (4.19%, 9/215), gestational hypertension disease (10.70%, 23/215), GDM (4.19%, 9/215), FGR (9.77%, 21/215) or low birth weight infants (8.37%, 18/215) among the TPOAb (-) treated group, the TPOAb (-) untreated group [3.80% (23/605), 4.13% (25/605), 10.91% (66/605), 5.95% (36/605), 9.75% (59/605), 8.10% (49/605), respectively] and the control group. CONCLUSIONS: (1) The incidence of abortion, premature delivery, gestational hypertension disease, GDM, FGR and low birth weight infants could be increased in women with SCH in early pregnancy. (2) Thyroxine treatment could reduce the incidence of pregnancy complications in women with SCH in early pregnancy.