Continuous flow biocatalysis: synthesis of purine nucleoside esters catalyzed by lipase TL IM from Thermomyces lanuginosus.

Purine nucleoside ester is one of the derivatives of purine nucleoside, which has antiviral and anticancer activities. In this work, a continuous flow synthesis of purine nucleoside esters catalyzed by lipase TL IM from Thermomyces lanuginosus was successfully achieved. Various parameters including solvent, reaction temperature, reaction time/flow rate and substrate ratio were investigated. The best yields were obtained with a continuous flow microreactor for 35 min at 50 °C with the substrate ratio of 1 : 5 (nucleosides to vinyl esters) in the solvent of tert-amyl alcohol. 12 products were efficiently synthesized with yields of 78-93%. Here we reported for the first time the use of lipase TL IM from Thermomyces lanuginosus in the synthesis of purine nucleoside esters. The significant advantages of this methodology are a green solvent and mild conditions, a simple work-up procedure and the highly reusable biocatalyst. This research provides a new technique for rapid synthesis of anticancer and antiviral nucleoside drugs and is helpful for further screening of drug activity.

Preparation of Aminated Sodium Lignosulfonate and Efficient Adsorption of Methyl Blue Dye.

The aminated sodium lignosulfonate (AELS) was prepared through a Mannich reaction and characterized via FT-IR, TG, SEM and XPS in this study. Subsequently, the adsorption capacity of AELS for methyl blue (MB) was evaluated under various conditions such as pH, adsorbent dosage, contact time, initial concentration and temperature. The adsorption kinetics, isotherms and thermodynamics of AELS for methyl blue were investigated and analyzed. The results were found to closely adhere to the pseudo-second-order kinetic model and Langmuir isotherm model, suggesting a single-molecular-layer adsorption process. Notably, the maximum adsorption capacity of AELS for methyl blue (153.42 mg g-1) was achieved under the specified conditions (T = 298 K, MAELS = 0.01 g, pH = 6, VMB = 25 mL, C0 = 300 mg L-1). The adsorption process was determined to be spontaneous and endothermic. Following five adsorption cycles, the adsorption capacity exhibited a minimal reduction from 118.99 mg g-1 to 114.33 mg g-1, indicating good stability. This study contributes to the advancement of utilizing natural resources effectively and sustainably.

Development of a green, concise synthesis of nicotinamide derivatives catalysed by Novozym® 435 from Candida antarctica in sustainable continuous-flow microreactors.

An increasing number of studies have shown that many nicotinamide derivatives exhibited extensive biological activities, such as anti-inflammatory and antitumor activity. In this paper, a green, concise synthesis of nicotinamide derivatives in sustainable continuous-flow microreactors catalysed by Novozym® 435 from Candida antarctica has been developed. Application of an easily obtainable and reusable lipase in the synthesis of nicotinamide derivatives from methyl nicotinate and amines/benzylamines reacted for 35 min at 50 °C led to high product yields (81.6-88.5%). Environmentally friendly tert-amyl alcohol was applied as a reaction medium. Substantially shorter reaction times as well as a significant increase in the product yield were obtained as compared to the batch process. This innovative approach provides a promising green, efficient and rapid synthesis strategy for pharmaceutical synthesis and further activity research of novel nicotinamide derivatives.

Zinc Oxide-Loaded Cellulose-Based Carbon Gas Sensor for Selective Detection of Ammonia.

Cellulose-based carbon (CBC) is widely known for its porous structure and high specific surface area and is liable to adsorb gas molecules and macromolecular pollutants. However, the application of CBC in gas sensing has been little studied. In this paper, a ZnO/CBC heterojunction was formed by means of simple co-precipitation and high-temperature carbonization. As a new ammonia sensor, the prepared ZnO/CBC sensor can detect ammonia that the previous pure ZnO ammonia sensor cannot at room temperature. It has a great gas sensing response, stability, and selectivity to an ammonia concentration of 200 ppm. This study provides a new idea for the design and synthesis of biomass carbon-metal oxide composites.

Design, synthesis, and herbicidal activity of indole-3-carboxylic acid derivatives as potential transport inhibitor response 1 antagonists.

Auxins as an important class of phytohormones play essential roles in plant life cycle; therefore, developing compounds with auxin-like properties for plant growth regulation and weed control applications is of great significance. Herein, we reported the design, synthesis, and herbicidal activity evaluation of a series of novel indole-3-carboxylic acid derivatives as auxin receptor protein TIR1 antagonists. Petri dish herbicidal activity assay demonstrated that most of the as-synthesized target compounds exhibited good-to-excellent inhibition effects (60-97% inhibitory rates) on roots and shoots of both dicotyledonous rape (B. napus) and monocotyledonous barnyard grass (E. crus-galli). The inhibition rates of compounds 10d and 10h reached up to 96% and 95% for the root of rape (B. napus) at 100 mg/L, and they also maintained 92% and 93% inhibition rates even if at 10 mg/L, respectively. Molecular docking revealed that the interactions between these synthesized target compounds and TIR1 protein include tight π-π stacking, hydrogen bond, and hydrophobic interactions. This work expands the range of auxin chemistry for the development of new auxin mimic herbicides.

A sustainable innovation for the tandem synthesis of sugar-containing coumarin derivatives catalyzed by lipozyme TL IM from Thermomyces lanuginosus in continuous-flow microreactors.

We developed an efficient and environmentally friendly two-step tandem methodology for the synthesis of sugar-containing coumarin derivatives catalyzed by lipozyme TL IM from Thermomyces lanuginosus in continuous-flow microreactors. Compared to those observed for other methods, the salient features of this work including green reaction conditions, short residence time (50 min), and catalysts are more readily available and the biocatalysis reaction process is efficient and easy to control. This two-step tandem synthesis of coumarin derivatives using the continuous-flow technology is a proof of concept that opens the use of enzymatic microreactors in coumarin derivative biotransformations.

The convenient Michael addition of imidazoles to acrylates catalyzed by Lipozyme TL IM from Thermomyces lanuginosus in a continuous flow microreactor.

A fast and green protocol for the Michael addition of imidazoles to acrylates catalyzed by Lipozyme TL IM from Thermomyces lanuginosus in a continuous flow microreactor was developed. In contrast with existing methods, this method is simple (35 min), uses mild reaction conditions (45 °C) and is environmentally friendly. This enzymatic Michael addition performed in continuous flow microreactors is an innovation that may open up the use of enzymatic microreactors in imidazole analogue biotransformations.

Removal of methylene blue from aqueous solution by modified bamboo hydrochar.

Four hydrochars (labeled as HC, AHC, MHC, and MAHC, respectively) were prepared by hydrothermal carbonization of bamboo with and without chlorane or followed by NaOH modification. Various techniques were adopted to characterize the physicochemical properties of hydrochars and the removal of methylene blue (MB) by these hydrochars from aqueous solution was investigated. The MB adsorption isotherm and kinetic onto MAHC and MHC can be preferably interpreted by Langmuir adsorption mode and the pseudo-second-order model, respectively. Thermodynamic parameters implied that adsorption was a spontaneous and exothermic process. The adsorption capacity of MAHC was 655.76 mg g-1, which was 2-3 times compared to that of MHC (268.93 mg g-1) at 303 K. The high adsorption capacity of MAHC for MB suggests that hydrothermal carbonization in acidic medium followed by alkaline treatment has the potential application to produce efficient MB adsorbents used in wastewater treatment.

Enzymatic synthesis of nucleoside analogues from uridines and vinyl esters in a continuous-flow microreactor.

We achieved the effective controllable regioselective acylation of the primary hydroxyl group of uridine derivatives catalyzed by Lipase TL IM from Thermomyces lanuginosus with excellent conversion and regioselectivity. Various reaction parameters were studied. These regioselective acylations performed in continuous flow microreactors are a proof-of-concept opening the use of enzymatic microreactors in uridine derivative biotransformations.

A genetic variant in pre-miR-27a is associated with a reduced cervical cancer risk in southern Chinese women.

OBJECTIVE: MicroRNAs (miRNAs) play critical roles in cervical carcinogenesis. Common single nucleotide polymorphisms (SNPs) in pre/pri-miRNAs may change their property through altering miRNAs expression and/or maturation. Here we aimed to investigate the influence of three common SNPs in pre/pri-miRNAs (pri-miR-26a-1 rs7372209, pre-miR-27a rs895819 and pri-miR-100 rs1834306) on individual susceptibility to cervical cancer. METHODS: We genotyped these three polymorphisms in 103 cervical cancer cases and 417 cancer-free female subjects using polymerase chain reaction-ligation detection reaction (PCR-LDR) method. Unconditional logistic regression analysis was utilized to estimate the association between these polymorphisms and the risk of cervical cancer. RESULTS: In a logistic regression analysis, we found that the rs895819 polymorphism in pre-miR-27a exhibited a significant effect on cervical cancer risk; T allele (OR = 0.68, 95% CI = 0.49-0.95, P = 0.025), and CT (OR = 0.33, 95% CI = 0.15-0.74, P = 0.007) or TT (OR = 0.33, 95% C I= 0.15-0.72, P = 0.006) genotype were associated with the decreased risk, compared to C and CC respectively. As we used further genotype association models, we found a similar trend of the association in additive (OR = 0.70, P = 0.041) and recessive model (OR = 0.33, P = 0.004). We did not detect any association of the other two SNPs in pri-miR-26a-1 (rs7372209) and pri-miR-100 (rs1834306) with cervical cancer risk. CONCLUSION: Our study provides the first evidence that the miR-27a rs895819 polymorphism is associated with a decreased risk of cervical cancer in southern Chinese women.

The MBD4 Glu346Lys polymorphism is associated with the risk of cervical cancer in a Chinese population.

OBJECTIVE: Methyl-CpG binding domain 4 (MBD4) protein functions as a DNA repair enzyme and plays an important role in maintaining genome integrity and carcinogenesis. The polymorphisms in the MBD4 gene may be associated with differences in DNA repair capacity and thereby influence an individual's susceptibility to cervical cancer. To verify this hypothesis, we examined the potential association between the MBD4 Glu346Lys polymorphism (rs140693, G>A) and the risk of cervical cancer in a Chinese population. METHODS: We genotyped the MBD4 Glu346Lys polymorphism in 146 cervical cancer cases and 320 healthy female subjects using polymerase chain reaction-based restriction fragment length polymorphism method. Unconditional logistic regression analysis was used to estimate the association between the genotypes and the risk of cervical cancer. RESULTS: We observed a significantly decreased risk of cervical cancer associated with the heterozygous Lys/Glu genotype (odds ratio [OR], 0.60; 95% confidence interval [CI], 0.36-0.99; P = 0.046) and the homozygous Glu/Glu genotype (OR, 0.52; 95% CI, 0.30-0.89; P = 0.018), compared with the Lys/Lys homozygotes. Moreover, the reduced cervical cancer risk was more predominant among younger subjects or human papillomavirus-positive individuals carrying Glu/Glu genotypes (OR, 0.33; 95% CI, 0.14-0.78, P = 0.011; and OR, 0.27; 95% CI, 0.09-0.75, P = 0.013, respectively). CONCLUSIONS: The MBD4 codon 346 polymorphism may play a role in cervical cancer susceptibility in the Chinese population. Further larger case-control and functional studies are needed to validate these findings.

Regulatory Effect of Peptidoglycan on the Expression of Toll-Like Receptor 2 mRNA and Proteins in Trophoblast Cell Line TEV-1 Cells.

Objective. To investigate the regulatory effect of peptidoglycan on the expression of human Toll-like receptors 2 (TLR2) mRNA and proteins in the human extravillous trophoblast cell line (TEV-1). Methods. TEV-1 cells were incubated with different doses of peptidoglycan. The expression of TLR2 mRNA and protein was detected by reverse transcriptase-polymerase chain reaction (RT-PCR) and immunocytochemistry SP staining. Results. TLR2 was expressed in TEV-1 cells and localized to both the cytoplasm and plasma membrane. Compared with the untreated control, TEV-1 cells incubated with 30 µg/ml peptidoglycan significantly upregulated the expression of TLR2 mRNA and protein after 12 hours of treatment (P < .01). However, the expression of TLR2 mRNA and protein was decreased but had no significant difference compared with the control (P > .05) after 24 hours of treatment. On the other hand, 10 µg/ml peptidoglycan did not seem to have regulatory effect on mRNA and protein expression of TLR2 (P > .05). Conclusion. Peptidoglycan has a role in regulating the expression of TLR2 mRNA and protein in TEV-1 cells. It suggests that the trophoblast cells may play important role in the immune response at the fetal-maternal interface and affect the result of pregnancy by expressing TLR2.

[An optoelectronic cervical cancer screening system for screening cervical cancer: comparison with cervical cytology].

OBJECTIVE: To study the clinical value of optoelectronic cervical cancer screening system (TruScreen, TS) in the screening of cervical cancer in comparison with cervical cytology test. METHODS: A total of 392 patients were screened by TS, Pap, TCT, and HPV using the pathological and colposcopical results as the golden standard. The sensitivity, specificity, Kappa value and the area of under ROC of each method and their combinations (parallel tests) were compared. RESULTS: The sensitivity of TS, Pap, TCT and HPV were 32.2%, 42.2%, 74.4% and 47.8%, with specificity of 96.7%, 93.7%, 78.8% and 84.8% in detecting cervical cancer, respectively. The sensitivity of the parallel tests, namely TCT/HPV, TCT/TS, Pap/TS and HPV/TS were 65.6%, 87.8%, 82.2% and 86.7%, with the specificity of 81.1%, 74.5%, 75.8% and 67.2%, respectively. In light of the areas of under ROC, significant differences were noted between the parallel tests of TS/Pap and TS/TCT (P<0.05), but not between TCT/Pap and TCT/TS (P>0.05); significant differences were found between the parallel tests with TS and those without TS (P<0.05), but not between TS alone and the parallel tests incorporating TS (P>0.05), nor between the 4 parallel tests (P>0.05). CONCLUSION: As a new modality for early screening of cervical carcinoma, TS offers a means for real-time cancer detection with better diagnostic efficacy than Pap and HPV and equivalent efficacy to TCT. The combination of TS and cytological tests can further enhance the diagnostic accuracy.

Association between the CDC6 G1321A polymorphism and the risk of cervical cancer.

INTRODUCTION: Cell division cycle protein 6 (CDC6) plays critical roles in DNA replication and carcinogenesis. The biological significance of the CDC6 G1321A polymorphism (V441I, rs13706) on cervical carcinogenesis is still unknown. Here, we examined the potential influence of this polymorphism on cell proliferation and the individual's susceptibility to cervical cancer. METHODS: We genotyped the CDC6 G1321A polymorphism in 87 cervical cancer cases and 110 healthy female subjects. Unconditional logistic regression analysis was used to estimate the association between the genotypes and the risk of cervical cancer. The BrdU incorporation assay was applied to analyze the effect of this polymorphism on cell proliferation. RESULTS: Compared with the GG homozygotes, the cervical cancer risk was significantly reduced in the individuals with the heterozygous AG genotype (odds ratio [OR], 0.53; 95% confidence interval [CI], 0.28-0.98; P = 0.042) or the homozygous AA genotype (OR, 0.29; 95% CI, 0.09-0.89; P = 0.030). Further stratified analyses showed that the decreased risk of cervical cancer was more evident among younger subjects (≤44 years old) with the AG or AA genotypes (OR, 0.44; 95% CI, 0.21-0.92; P = 0.029 and OR, 0.12; 95% CI, 0.03-0.61; P = 0.010, respectively). The BrdU incorporation assay showed that 293T cells transfected with CDC6-441I (1321A) had a lower proliferation rate in comparison with those transfected with CDC6-441V (1321G), although the difference did not reach statistical significance at the 0.05 level. CONCLUSIONS: The CDC6 G1321A polymorphism may contribute to the risk of cervical cancer. Further studies with more subjects and in diverse ethnic populations are necessary to confirm the general validity of our findings.

[Clinical analysis on long term effect of microwave endometrial ablation in treatment of menorrhagia.].

OBJECTIVE: To evaluate long term effect and related factors in patients with menorrhagia treated by microwave endometrial ablation (MEA). METHODS: Total of 334 women with menorrhagia were treated by MEA, the range of age was from 29 to 59 years old. Among them, 59 cases were complicated by adenomyosis. All the patients were followed up on the change of menstrual cycle, the amount of flow, improvement of anaemia and complication. Fifty-three women underwent outpatient diagnostic hysteroscopy, the biopsy tissue was taken from the endometrium for histopathological examination. The mean duration of follow-up was 64.7 months (3 - 96 months). RESULTS: The overall curative rate was 91.3% (305/334), of which amenorrhea rate was 49.7% (166/334), menstruation reduction rate was 41.6% (139/334) ; 71.1% (140/197) of the cases who previously had dysmenorrhea had relieved their pelvic pain and the satisfactory rate was 91.9% (307/334). Among patients > 40 years, 92.9% (196/211) of operation effective rate, 93.8% (198/211) of satisfactory rate and 64.9% (137/211) of amenorrhea rate were obtained, while patients