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Hemoglobin (Hb) is a hemoprotein containing iron porphyrin, which can catalyse a variety of unnatural reactions. Due to its poor reusability and stability, in this study, we developed a new method to prepare Hb-Cu3(PO4)2 hybrid nanoflowers (HNFs) by co-incubating Hb with Cu2+. This immobilized Hb was used to catalyse the synthesis of ethyl N-phenylglycinate via the carbene N–H insertion reaction. Under the optimum reaction conditions (aniline 1 mmol; ethyl diazoacetate 1 mmol; deionized (DI) water 10 ml; catalyst (protein content: 15 mg); sodium hydrosulfite 25 mg; 25 °C; 12 h), the catalytic yield of Hb-Cu3(PO4)2 HNFs reached as high as 87% and that of free Hb was 74%. In addition, Hb-Cu3(PO4)2 HNFs can maintain a high catalytic performance after 15 cycles and still achieve yields close to 70% of the initial yield after 60 days of storage, indicating that Hb-Cu3(PO4)2 HNFs have a high potential for application in Hb-catalysed organic reactions. [ABSTRACT FROM AUTHOR]

Sentinel lymph node biopsy (SLNB) is currently used as a routine treatment for patients with breast cancer. However, it may not be applicable for patients with male breast cancer (MBC), because they have notably different clinicopathological features from those occurring in females. There is a lack of evidence of SLNB application and safe exemption from axillary lymph node dissection (ALND) in patients with MBC. This study aimed to evaluate the application of SLNB to provide information for the standardized treatment of patients with MBC. The MBC patient records from 4 institutions ranging from January 2001 to November 2020 were retrospectively reviewed. There were 220 patients with MBC with a median age of 60 (range 24-88) years and an average tumor size of 2.3 cm (range 0.5 cm-6.5 cm). Sixty-six percent of patients underwent SLNB, and 39% of them showed positive results. A total of 157 patients underwent ALND, while only half of them had positive nodes, causing unnecessary complications. For patients in the clinical early stage, we found that the SLNB showed a noninferiority to the ALND treatment in DFS (P =.18) and OS (P =.055). In conclusion, there are certain obstacles to the broad application of SLNB due to the lower proportion of patients with clinically negative lymph nodes. However, it is undeniable that SLNB can safely and effectively exempt patients with MBC at early stage with clinically negative nodes from ALND to reduce subsequent complications. It is still an ideal criterion for the axillary staging of patients with MBC. Sentinel lymph node biopsy (SLNB) is used as a routine treatment for patients with breast cancer; however, it may not be useful for male patients because of the differences in clinicopathological features of male versus female patients. This study evaluated the application of SLNB to provide information for the standardized treatment of patients with metastatic breast cancer. [ABSTRACT FROM AUTHOR]

As a base structural unit, 1,4-dihydropyridines (DHPs) containing benzosultams widely exist in bioactive molecules and drugs. These compounds are generally synthesized by organic-base catalyzed methods that require specifically functionalized substrates or harsh conditions. Herein, a [3+3] annulation reaction of cyclic N-sulfonyl ketimine with various substituted isatylidene malononitrile or benzylidene malononitriles was documented. This biocatalytic strategy provides a green route for synthesis of 1,4-DHPs containing benzosultams, with good functional groups compatibility and yields. Under optimal conditions, lipase leads to the formation of 1,4-DHPs containing benzosultams in up to 87% yield. [ABSTRACT FROM AUTHOR]

A metal‐free, straightforward, non‐hazardous reagent‐added, one‐pot approach for the efficient synthesis of 2‐arylimino‐2H‐chromenes with high yields was developed for the first time in this report through the coupling of salicylaldehydes with β‐ketothioamides, which was catalyzed by lipase in water. This green strategy provides an efficient method to obtain various 2‐arylimino‐2H‐chromenes and enriches the practical application of biocatalysis. [ABSTRACT FROM AUTHOR]

The development of non-natural enzymatic catalysis is important for multicomponent tandem organic transformations. However, the delicate acting environments of biological enzymes still present some challenges in the synthesis of spirooxindole skeleton via enzymatic catalysis. To address these issues, a lipase-catalyzed method was developed for the synthesis of spirooxindole frameworks. Using easily available isatins, cycloketones, and malononitriles as substrates, mild reaction conditions, and a reasonable reaction time, moderate to good yields (67–92%) and excellent functional group tolerance were accomplished via this protocol. The related mechanism explanation is also speculated in this paper. [ABSTRACT FROM AUTHOR]

There is no clear treatment guideline or individualized treatment plan for triple-negative breast cancer (TNBC). The aim of this study was to investigate more effective targets for TNBC-targeted therapy. MDA-MB-231 and BT549 cell lines were used to explore the function of LINC00649 on the proliferation, invasion, and migration of TNBC cells. A mice subcutaneous tumor model and a pulmonary metastasis model was established to identify the role of LINC00649 on the growth and metastasis of TNBC in vivo. LINC00649 was found to be a key molecule involved in the occurrence and development of TNBC by screening of public databases and detection of TNBC clinical samples. LINC00649 increased hypoxia-inducible factor 1α (HIF-1α) mRNA stability and protein expression by interacting with the nuclear factor 90 (NF90)/NF45 complex. In vitro, interference with LINC00649 inhibits MDA-MB-231 and BT549 cell proliferation, migration, and invasion, and the addition of HIF-1α revised this effect. In vivo experiments showed that LINC00649 promoted the growth and metastasis of TNBC. We demonstrated that LINC00649 interacts with the NF90/NF45 complex to increase the mRNA stability of HIF-1α and up-regulate HIF-1α expression, thereby inducing the proliferation, invasion, and migration of TNBC cells as well as tumor growth and metastasis. [ABSTRACT FROM AUTHOR]

Background: Increasing evidence has suggested that circular RNAs (circRNAs) may act as an important regulatory factor in tumor progression. However, how circRNAs exert their functions in triple‐negative breast cancer (TNBC) remains not clearly understood. Methods: First, circRNA microarrays were conducted to identify aberrantly expressed circRNAs in TNBC tissues. Kaplan–Meier survival analysis was conducted to calculate the correlation between the level of hsa_circRNA_102229 and outcomes of patients with TNBC. The effect of hsa_circRNA_102229 and serine/threonine‐protein kinase PFTAIRE 1 (PFTK1) on TNBC cells was clarified by cell counting kit‐8, transwell and wound healing assays, as well as by a flow cytometry. The molecular mechanism of hsa_circRNA_102229 was clarified through bioinformatics, a dual‐luciferase reporter assay, western blotting, fluorescence in situ hybridization and real‐time polymerase chain reaction. Tumor xenograft experiments were performed to analyze growth and metastasis of TNBC in vivo. Results: In TNBC tissues and cells, hsa_circ_102229 was remarkably up‐regulated. Patients with TNBC presenting high hsa_circ_102229 exhibited poor prognosis. Moreover, hsa_circ_102229 could promote the migration, proliferation and invasion, whereas it inhibited the apoptosis of TNBC cells. Furthermore, hsa_circ_102229 directly targeted miR‐152‐3p and could regulate the expression of PFTK1 by targeting miR‐152‐3p. Rescue assays suggested that hsa_circ_102229 may exert its function in TNBC cells by regulating PFTK1. Additionally, knockdown of hsa_circ_102229 slowed down TNBC tumorigenesis and lung metastasis in a tumor xenograft animal model. Conclusions: Hsa_circ_102229 might serve as a competing endogenous RNA (ceRNA) to modulate PFTK1 expression via regulating miR‐152‐3p to affect the functions of TNBC cells. Hsa_circ_102229 acts as a newly discovered biomarker for TNBC treatment. [ABSTRACT FROM AUTHOR]

Background: This study aimed to explore the biological functions of G-quadruplex-forming sequence containing lncRNA (GSEC) in triple negative breast cancer (TNBC). Methods: The expression of GSEC in TNBC tissues was evaluated by qRT-PCR. Cell viability was evaluated by Cell Counting Kit-8 assay. Cell proliferation was evaluated by 5-ethynyl-20-deoxyuridine (EdU) staining assay. Cell invasion and migration were evaluated by Transwell assay. Gain- and loss-function assays were performed to assess the biological functions of GSEC in TNBC. The interactions between GSEC, miR-202-5p and AXL were determined by luciferase report assay and RNA immunoprecipitation (RIP) assay. In addition, a nude mouse xenograft model was used to confirm the oncogenic role of GSEC in TNBC. Results: GSEC was significantly upregulated in TNBC tissues and cancer cell lines, and high level of GSEC was associated with advanced tumor stage, positive lymph-node metastasis and the poor prognosis of TNBC patients. Knockdown of GSEC effectively inhibited TNBC cell proliferation, invasion and migration in vitro. GSEC regulated the expression of AXL by directly sponging miR-202-5p. Downregulation of miR-202-5p attenuated GSEC knockdown-induced inhibition on TNBC cell proliferation, invasion and migration in vitro. Meanwhile, overexpression of AXL obviously reversed the inhibitory effects of miR-202-5p mimics in TNBC progression in vitro. Conclusion: GSEC functioned as a potential oncogene and promoted AXL-mediated TNBC progression by sponging miR-202-5p, which might be a novel diagnostic and therapeutic target for TNBC. [ABSTRACT FROM AUTHOR]

Long non-coding RNAs (lncRNAs) may be a regulatory factor of tumorigenesis. However, it is unclear what its biomechanisms are in breast cancer. In this study, different lncRNAs were detected in breast cancer through microarray analysis (GSE119233) and LINC01705 was selected for further study. qRT-PCR was then utilized for the detection of LINC01705 expression in breast cancer cells. A transwell assay, flow cytometry, 5-ethynyl-2′-deoxyuridine (EdU), a cell counting Kit-8 (CCK-8), and a wound-healing assay were performed to determine cell migration, invasion, apoptosis, and proliferation in breast cancer, respectively. For the identification of potential targets of LINC01705, dual-luciferase reporter gene and bioinformatics assays were conducted. Moreover, for the clarification of their interaction and roles in the regulation of the occurrence of breast cancer, Western blotting and RIP assays were conducted. Our findings revealed high LINC01705 expression in breast cancer tissues relative to adjacent non-cancerous tissues (n = 40, P < 0.001). Overexpression of LINC01705 notably enhanced cell migration and proliferation in breast cancer. In addition, LINC01705 positively regulated the translocated promoter region, nuclear basket protein (TPR) through competition with miR-186-5p. In conclusion, our results suggest that LINC01705 is implicated in the progression of breast cancer via competitively binding to miR-186-5p as a competing endogenous RNA (ceRNA), thereby regulating TPR expression. [ABSTRACT FROM AUTHOR]

Designing biomimetic scaffolds with in vivo–like microenvironments using biomaterials is an essential component of successful tissue engineering approaches. The intestinal smooth muscle layers exhibit a complex tubular structure consisting of two concentric muscle layers in which the inner circular layer is orthogonally oriented to the outer longitudinal layer. Here, a 3D bi‐layered tubular scaffold is presented based on flexible, mechanically robust, and well aligned silk protein microfibers to mimic the native human intestinal smooth muscle structure. The scaffolds are seeded with primary human intestinal smooth muscle cells to replicate intestinal muscle tissues in vitro. Characterization of the tissue constructs reveals good biocompatibility and support for cell alignment and elongation in the different scaffold layers to enhance cell differentiation and functions. Furthermore, the engineered smooth muscle constructs support oriented neurite outgrowth, a requisite step to achieve functional innervation. These results suggest these microfiber scaffolds as functional templates for in vitro regeneration of human intestinal smooth muscle systems. The scaffolding provides a crucial step toward engineering functional human intestinal tissue in vitro, as well as engineering other types of smooth muscles in terms of their similar phenotypes. Such utility may lead to a better understanding of smooth muscle associated diseases and treatments. [ABSTRACT FROM AUTHOR]

Conical refraction of optical beams with circular symmetry is often analyzed using Belsky–Khapalyuk–Berry (BKB) theory; however, for beams with noncircular symmetry, it is difficult to obtain analytical expressions for far-field diffraction patterns. We propose a method, based on fast Fourier transform (FFT), for calculating conical refraction of beams with noncircular symmetry and verify it experimentally using a quasi-plane wave passing through a square aperture and focusing lens. Excellent agreement between theoretical and experimental results has been achieved. [ABSTRACT FROM PUBLISHER]

There are conflicting reports on the heavy metal levels in human semen with different fertilities. The purpose of this analysis is to merge and analyze the differences of heavy metal lead (Pb), cadmium (Cd), zinc (Zn), and copper (Cu) levels in male semen with normal and low fertilities. All documents in both Chinese and English were collected from the PubMed, Web of Science, and Chinese National Knowledge Infrastructure (CNKI) database from inception date to February 19, 2016. We have used RevMan software (version 5.2) for the meta-analysis and Stata software (version 12.0) for the meta-regression and sensitivity analyses. A total of 20 literatures were included in the study. The results of the meta-analysis indicate a significant difference between fertility with three metal ions (Pb, Cd, Zn) while no significant difference with copper, detailed as follows: (i) 10 studies on the lead concentrations with a standardized mean difference (SMD) = 2.07, 95 %CI (0.97, 3.17), P < 0.01; (ii) 13 studies on the cadmium concentrations with an SMD = 0.75, 95 %CI (0.44, 1.07), P < 0.01; (iii) 8 studies on the concentrations of zinc with an SMD = −0.61, 95 %CI (−1.08, −0.14), P < 0.01; and (iv) 9 studies on the copper concentrations with an SMD = 0.42, 95 %CI (−0.29, 1.13), P = 0.247. The results indicate that the men with low fertility have higher semen Pb and Cd levels and lower semen Zn levels; more studies are needed to indicate the association of the semen copper level with fertility. [ABSTRACT FROM AUTHOR]

The reproductive system is sensitive to lead (Pb) toxicity, which has long been an area of research interest, but the underlying mechanisms remain to be illustrated. Peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) is pivotal in mitochondrial function. In this study, mouse testis Sertoli cells (TM4 cells), PGC-1α lower-expression (PGC-1α(−)) TM4 cells and PGC-1α overexpression (PGC-1α(+)) TM4 cells were used to explore the protective roles of PGC-1α against lead toxicity on the mouse reproductive system. Lead acetate (PbAc) exposure decreased the expression level of PGC-1α, increased the intracellular level of reactive oxygen species (ROS), and reduced the level of ATP in the three TM4 cell lines. The effects of PbAc on intracellular ATP level and on ROS content were significantly weakened in PGC-1α(+)TM4 cells versus TM4 cells and were significantly amplified in PGC-1α(−)TM4 cells versus TM4 cells. These results suggest that PGC-1α is a protective factor against PbAc-induced oxidative stress and energy metabolism dysfunction in the mouse reproductive system, thereby holding the potential of being developed as a preventive or therapeutic strategy against disorders induced by lead exposure. [ABSTRACT FROM AUTHOR]

A structure of serially coupled dumbbell microring resonator (SCDMRR) is proposed based on Vernier effects to obtain wider free spectral range (FSR), and a new kind of two-dimensional optical en/decoder is designed taking advantage of the SCDMRR. Numerical simulations are done to analyze reflection spectrum of the SCDMRR and test performance of the proposed en/decoder according to the coupled mode theory. In addition, the coupling coefficients of both ring-bus and ring-ring are optimized to suppress the spurious mode. Furthermore, a comparison is performed between the en/decoder based on SCDMRRs and the en/decoder using ordinarily coupled identical three-order-ring resonators (OCITRR). The results show that the FSR is 13 nm for SCDMRR with the ring radius of 40–30–40 μm, which is about four to five times larger than that of OCITRR. Such FSR will contain more column numbers of parallel-coupled MRR and the code cardinality generated by the proposed device is 3.43E17. For the SCDMRR-based en/decoder, the peak to wing ratio (P/W) of autocorrelation signal and peak power ratio (P/C) between the auto-/cross-correlations are 6.39 and 8.71, which have risen by approximately 33% and 8% against that of en/decoder based on OCITRR, respectively. [ABSTRACT FROM PUBLISHER]

The aim of this study was to investigate the relationship of blood lead (Pb) levels with copper (Cu), zinc (Zn), calcium (Ca), magnesium (Mg), iron (Fe), and hemoglobin (Hb) in children aged from 0-6 years in Wuhan, China. A total of 1047 children from six communities, which were randomly selected in Wuhan city and three communities, located in the urban area and others in the suburban area, were recruited for this study between November 2012 and July 2013. The levels of elements in the blood were detected using an atomic absorption spectrometer, and Hb level was tested by an automated hematology analyzer. The results showed that the mean blood lead level (BLL) is 33.72 ± 19.03 μg/L. The BLL was significantly higher among boys than girls ( P < 0.05). Higher BLL was also observed in suburbs compared to that in urban areas ( P < 0.05). The BLL and Zn level were gradually increased with age. The elevated rate of BLL in children was 20.9 %, while the Zn deficiency rate was 65.0 %. And, the level of Hb in higher BLL group was significantly lower. Negative correlations of the blood levels of Pb with those of Cu ( r = −0.087, P = 0.005), Mg ( r = −0.102, P = 0.001), and Fe ( r = −0.091, P = 0.003) were observed. These data suggested that the elevated rate of BLL in children from Wuhan is still higher according to the updated reference values in the USA. The deficiency of Cu, Mg, and Fe may indicate the elevation of lead absorption. The dietary supplement of Zn, Ca, and Fe in children requires more attention. [ABSTRACT FROM AUTHOR]

Sertoli cells around germ cells are considered a barrier that protects spermatogenesis from harmful influences. The transporter multidrug-resistance-associated protein 1 (MRP1) is a xenobiotic efflux pump that can export glutathione S-conjugated metabolites and xenobiotics from cells. In this study, the Mrp1 gene was stably knocked down in a mouse Sertoli cell line (TM4) using lentivirus vector-mediated RNA interference (RNAi) technology. Four shRNA interference sequences were chosen and designed to screen for the most effective shRNA in candidate cells. The results indicate that lentivirus vectors with high titres were generated and successfully transfected into TM4 cells with high efficiency. Puromycin was added to the culture medium to maintain constant selection during the establishment of the stable cell lines. The expression levels of Mrp1 mRNA and MRP1 protein in stably transfected TM4 cells were significantly lower than those in the control group. Importantly, the transport activity of MRP1 to Calcein and 5-carboxyseminaptharhodafluor (SNARF-1) were significantly reduced because of MRP1 silencing. Moreover, the silencing of the Mrp1 gene in the transfected TM4 cell lines remained highly stable for more than 6 months. These results suggest that the lentivirus-based RNAi stably knocks down the expression of the Mrp1 gene in the established TM4 cell line. This transfected TM4 cell line will provide a new and powerful tool to study the underlying mechanism of MRP1-mediated drug resistance and detoxication in the reproductive system. [ABSTRACT FROM AUTHOR]

Pseudomonas sp. lipase (PSL) was successfully immobilized on a novel hydrophobic polymer support through physical adsorption and the immobilized PSL was used for resolution of ( R, S)-2-octanol with vinyl acetate as acyl donor. Enhanced activity and enantioselectivity were observed from the immobilized PSL compared with free PSL. The effects of reaction conditions such as temperature, water activity, substrate molar ratio and the amount of immobilized lipase were investigated. Under optimum conditions, the residual ( S)-2-octanol was recovered with 99.5% enantiomeric excess at 52.9% conversion. The results also indicated that the immobilized PSL could maintain 94% of its initial activity even after reusing it five times. [ABSTRACT FROM AUTHOR]

Recently, significant efforts have been devoted into the study of the effect of hydrophobic supports on the catalytic properties of immobilized lipases. It seems that immobilization lipases on hydrophobic supports is a simple and efficient method to improve the catalytic activity of lipases. In this study, the hydrophobic poly(N-propyl-norbornene-exo-2,3-dicarboximide)s with well-controlled molecular weight were synthesized by the living ring-opening metathesis polymerization, and the lipases from Pseudomonas sp. were then immobilized on these hydrophobic polymer supports through the physical adsorption. The immobilized lipases exhibited higher activity and enantioselectivity for the transesterification of 2-octanol than those of free lipases. Furthermore, we investigated the polymer molecular weight-mediated catalytic properties of immobilized lipases. It was found that the catalytic activity and E value of the immobilized lipases increased with the increase of the polymer molecular weight. At the polymeric molecular weight of about 40kDa, the highest E value (58 at 54.2% of conversion, enantiomeric excess = 99%) was reached. After the molecular weight of polymers getting higher than 40 kDa, catalytic activity and Evalue of the immobilized lipase decreased. [ABSTRACT FROM AUTHOR]

Polymer-impregnated silica sol-gel composite materials are hosts for organics in advanced optics application. An oligo-phenylene vinylene derivative 4,4′-(1,4- phenylene dithenylene)-bis-(N-methyl pyridinium iodide) (OPVD) was introduced to poly(hydroxyethyl methacrylate) (PHEMA)-impregnated silica composite film by the sol-gel process. By comparing the X-ray diffraction, U V-visible spectra, steady-state and time-resolved fluorescence spectra of OPVD in three solid matrices (PHEMA/silica composite film, pure PHEMA film, and pure silica film), the similar results of PHEMA/silica composite film and pure PHEMA film demonstrate that the OPVD is primarily surrounded by a PHEMA-like environment in the composite matrix. The model of such structure is presented, which is useful for further understanding and optimizing of properties of doped sol-gel materials. [ABSTRACT FROM AUTHOR]