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Cisplatin is an effective chemotherapeutic agent in facilitating the inhibition of proliferation, migration, and invasion in cancerous cells. However, the detailed mechanism of the regulation by cisplatin of human breast cancer cells is still unclear. This study aimed to investigate the mechanism of kruppel-like factor 2 (KLF2) transcription factor in cisplatin therapy for breast cancer. RT-qPCR was performed to quantify the expression of KLF2 and WEE1 in clinical tissue samples from breast cancer patients and in MDA-MB-231 cells. ChIP assay and dual-luciferase reporter assay were used to analyze the potential-binding sites of KLF2 and WEE1 promoter. Gain- or loss-of-function approaches were used to manipulate KLF2 and WEE1 in cisplatin-treated MDA-MB-231 cells, and the mechanism of KLF2 in breast cancer was evaluated both via CCK-8 assay, flow cytometry, Transwell assay, and Western blot. Further validation of the KLF2 was performed on nude mouse models. Breast cancer tissues and cells showed a relative decline of KLF2 expression and abundant WEE1 expression. Cisplatin inhibited the proliferation, migration, and invasion of MDA-MB-231 cells. Overexpression of KLF2 enhanced the inhibitory effect of cisplatin on the malignant characteristics of MDA-MB-231 cells in vitro. KLF2 targeted WEE1 and negatively regulated its expression, thus enhancing the sensitivity to cisplatin of breast cancer cells as well as tumor-bearing mice. Overall, these results suggest that KLF2 can potentially inhibit WEE1 expression and sensitize breast cancer cells to cisplatin, thus presenting a promising adjunct treatment.

A number of kinesin proteins (KIFs) have been implicated in the development of multiple cancers. However, little is known about the expression and function of KIF15 in human breast cancer. Herein, we detected KIF15 expression in breast cancer tissues and paired adjacent normal tissues using immunohistochemistry and quantitative real-time polymerase chain reaction analysis, and the correlation of KIF15 expression with clinicopathological parameters was evaluated statistically. The role of KIF15 in cell proliferation, migration, tumor growth and metastasis of breast cancer cells was investigated in vitro and in vivo, and we explored potential molecular mechanisms underlying the effects of KIF15 in breast cancer through western blot analysis. The results revealed that increased KIF15 expression in breast cancer tissues were positively related with tumor size, lymph node metastasis and TNM stage, and higher KIF15 expression predicts a worse prognosis of patients with breast cancer. Furthermore, KIF15 knockdown markedly attenuated breast cancer cell proliferation, migration, tumor growth and metastasis in vitro and in vivo, and silenced KIF15 expression significantly inhibited the expression of phosphorylated AKT, phosphorylated JNK, and cyclin D1, while both p53 and p21 protein expressions were strongly enhanced. These results suggest that KIF15 is a potential oncogene in human breast cancer.

Background Hemostasis and repair are two essential processes in wound healing, yet early hemostasis and following vascularization are challenging to address in an integrated manner. Results In this study, we constructed a hemostatic sponge OBNC-DFO by fermentation of Komagataeibacterxylinus combined with TEMPO oxidation to obtain oxidized bacterial nanocellulose (OBNC). Then angiogenetic drug desferrioxamine (DFO) was grafted through an amide bond, and it promoted clot formation and activated coagulation reaction by rapid blood absorption due to the high total pore area (approximately 42.429 m2/g measured by BET). The further release of DFO stimulated the secretion of HIF-1α and the reconstruction of blood flow, thus achieving rapid hemostasis and vascularization in damaged tissue. This new hemostatic sponge can absorb water at a rate of approximate 1.70 g/s, rapidly enhancing clot formation in the early stage of hemostasis. In vitro and in vivo coagulation experiments (in rat tail amputation model and liver trauma model) demonstrated superior pro-coagulation effects of OBNC and OBNC-DFO to clinically used collagen hemostatic sponges (COL). They promoted aggregation and activation of red blood cells and platelets with shorter whole blood clotting time, more robust activation of endogenous coagulation pathways and less blood loss. In vitro cellular assays showed that OBNC-DFO prevailed over OBNC by promoting the proliferation of human umbilical vein endothelial cells (HUVECs). In addition, the release of DFO enhanced the secretion of HIF-1α, further strengthening vascularization in damaged skin. In the rat skin injury model, 28 days after being treated with OBNC-DFO, skin appendages (e.g., hair follicles) became more intact, indicating the achievement of structural and functional regeneration of the skin. Conclusion This hemostatic and vascularization-promoting oxidized bacterial nanocellulose hemostatic sponge, which rapidly activates coagulation pathways and enables skin regeneration, is a highly promising hemostatic and pro-regenerative repair biomaterial. Graphical Abstract

Our initial studies detected elevated levels of 3,4-dihydroxyphenyllactic acid (DHPLA) in urine samples of patients with severe heart disease when compared with healthy subjects. Given the reported anti-inflammatory properties of DHPLA and related dihydroxylated phenolic acids (DPAs), we embarked on an exploratory multi-centre investigation in patients with no urinary tract infections to establish the possible pathophysiological significance and therapeutic implications of these findings. Chinese and Caucasian patients being treated for severe heart disease or those conditions associated with inflammation (WBC ≥ 10 ×10

Objective: To investigate the function of IncRNA-TMPO-AS1 in breast cancer (BC) and to further explore its molecular mechanism. Methods: TMPO-AS1, miR-4731-5p and FOXM1 were quantitatively determined using qRT-PCR. CCK-8 assays, plate cloning experiments, wound healing and Transwell assays, and flow cytometry were used to assess the biological behaviors of BC cells. Dual-luciferase reporter assays were used to assess the interactions between TMPO-AS1 and its downstream targets. The apoptosis and cell cycle-related proteins were quantitatively determined using Western blot. Results: In the BC tissues and cells, TMPO-AS1 was significantly increased (P

The β2 adrenergic receptor (β2-AR) is a prototypical family A G protein-coupled receptor (GPCR) and an excellent model system for studying the mechanism of GPCR activation. Purified β2-AR was immobilized on macroporous silica gel to obtain liquid chromatographic stationary phase. The resulting phase was packed into a stainless steel column (4.6 × 50 mm, 7 μm) and used for on-line chromatographic system. When column oven temperature increased from 20.0 °C to 40.0 °C, uncomplete separate chromatographic peaks of ephedrine and pseudoephedrine as receptor conformational probe were gradually merged into one peak, meanwhile retention time and resolution of the probes were reduced correspondingly, which suggested that temperature could regulate protein conformation. Temperature-induced conformational change of immobilized β2-AR, especially changes at higher temperatures, indicated that constructed receptor chromatography could simulate fever disease state of human body and clarify receptor conformation change at pathological condition. At the same time this study could also provide new ideas for screening active components in pathological conditions.

Traditional Chinese medicine (TCM) represents a valuable resource for lead compounds discovery. Given the complexity of TCM components, analytical methods play a key role in novel drug development. In our study, we established a high specific and reliable bio-active components screen system, where β

Traditional Chinese medicine (TCM) represents a valuable resource for lead compounds discovery. Given the complexity of TCM components, analytical methods play a key role in novel drug development. In our study, we established a high specific and reliable bio-active components screen system, where β2 adrenergic receptor (β2-AR) was immobilized on silica by non-covalent bonds and packed into a stainless steel column (4.6 × 50 mm, 7 μm) to form β2-AR chromatography column. The column was further coupled with high performance liquid chromatography-time of flight tandem mass spectrometry (TOF-MS/MS). By utilizing this strategy, we successfully identified four β2-AR-targeting compounds: tetrahydroberberine, tetrahydrocolumbamine, fumarine and corydaline from Corydalis Rhizome. The association constants between β2-AR and tetrahydroberberine (9.04 × 104/M) as well as fumarine (4.30 × 104/M) were determined by frontal chromatography. We also found that these two compounds shared the identical binding site on immobilized β2-AR with corresponding concentrations of 6.67 × 10−4 M and 5.88 × 10−4 M, respectively. The newly established method represents an efficient tool to identify the target specific natural compounds.

Objective This study developed a novel protocol for creating an acute necrotizing pancreatitis model in rats using L-arginine. Methods Anesthetic laparotomy was performed on the upper abdomen, and the pancreatic parenchyma of Sprague-Dawley rats was injected with 1 mL of sterilized L-arginine solution at 5 different locations in the experimental group. Specifically, 2 different injection points in the head and body of the pancreas were chosen randomly, and 1 injection point in the tail of the pancreas was chosen randomly. The parenchyma of the pancreas was injected with 200 μL of an L-arginine solution at each point. The optimal dose of L-arginine per rat was 0.4 g/kg. Results Serum amylase activity increased significantly after targeted injection into the parenchyma of the pancreas. Pathological examination of the pancreas 24 hours after L-arginine injection revealed massive interstitial edema, apoptosis, and necrosis of acinar cells with an infiltration of neutrophils, granulocytes, and monocytes. Conclusions The present study developed an appropriate, workable, and reproducible rat model of acute necrotizing pancreatitis with higher survivability and success rates compared with previously published methods.

Although green fluorescence protein (GFP) and its antibody are widely used to track a protein or a cell in life sciences, the binding behavior between them remains unclear. In this work, diazo coupling method that synthesized a new stationary GFP was oriented immobilized on the surface of macro-porous silica gel by a phase. The stationary phase was utilized to confirm the validation of injection amount-dependent analysis in exploring protein-protein interaction that use GFP antibody as a probe. GFP antibody was proved to have one type of binding site on immobilized GFP. The number of binding site and association constant were calculated to be (6.41 ± 0.76) × 10(-10) M and (1.39 ± 0.12) × 10(9) M(-1). Further analysis by molecular docking showed that the binding of GFP to its antibody is mainly driven by hydrogen bonds and salt bridges. These results indicated that injection amount-dependent analysis is capable of exploring the protein-protein interactions with the advantages of ligand and time saving. It is a valuable methodology for the ligands, which are expensive or difficult to obtain.

This approach utilized N,N′-bis(carboxymethyl)-L-lysine (ANTA) coordinated to bivalent metal cation Ni2+, leaving free coordination sites for the reversible binding of gene recombinant histidine-tagged β2-adrenoceptor onto macropore silica. The amount of transient metal nickel ion on the support was determined by atomic absorption spectrophotometry. The novel protein oriented immobilization β2-AR column was evaluated by five β2-adrenoceptor agonists, applying frontal analysis. The association equilibrium constant for ligands on the column was 1.98 × 104 M−1 for salbutamol, 3.43 × 104 M−1 for clenbuterol, 2.09 × 104 M−1 for tulobuterol, 1.84 × 104 M−1 for terbutaline, 1.71 × 104 M−1 for methoxyphenamine and corresponding concentrations at binding sites were 7.46 × 10−6 M, 1.82 × 10−5 M, 2.16 × 10−5 M, 8.29 × 10−6 M and 3.88 × 10−5 M, respectively. The results obtained from breakthrough and nonlinear fitting indicated that all the drugs have a single binding site on the β2-adrenoceptor column. The present combined histidine-tagged protein method was reliable and exact in revealing interactions between receptor and drugs.

The β

The interaction between drugs and receptors is particularly important in revealing the drug acting mechanism and developing new leads. In this work, α 1-Adrenoceptor (α 1-AR) from HEK293 cell line is purified and immobilized on the surface of macro-pore silica gel to prepare an high-performance affinity chromatography stationary phase for the pursuit of drug–receptor interactions by competition zonal elution. Naftopidil is found to have only one type of binding site to α 1-AR with an association constant of 1.45 × 106 M−1 and a concentration of binding sites of 1.56 × 10−6 M, while terazosin hydrochloride proves to present two kinds of binding site on the receptor at which the association constants are determined to be 1.61 × 105 M−1 and 2.06 × 103 M−1, and the corresponding concentrations of the binding sites are 1.56 × 10−6 M and 1.11 × 10−3 M, respectively. It is concluded that the stationary phase containing attached α 1-AR can be used to realize the binding of a drug to the receptor.

A new mathematical model and frontal analysis were used to characterize the binding behavior of caffeic acid to human serum albumin (HSA) based on high-performance affinity chromatography. The experiments were carried out by injecting various mole amounts of the drug onto an immobilized HSA column. They indicated that caffeic acid has only one type of binding site to HSA on which the association constant was 2.75 × 104/m. The number of the binding site involving the interaction between caffeic acid and HSA was 69 nm. The data obtained by the frontal analysis appeared to present the same results for both the association constant and the number of binding sites. This new model based on the relationship between the mole amounts of injection and capacity factors assists understanding of drug–protein interaction. The proposed model also has the advantages of ligand saving and rapid operation. Copyright © 2014 John Wiley & Sons, Ltd.

A pilot-scale process has been developed for green and scalable synthesis of (±)-β-(3,4-dihydroxyphenyl) lactic acid ((±)-DSS) and their two important derivatives, namely, (±)-IDHP [(±)-isopropyl 2-hydroxy-3-(3,4-dihydroxyphenyl)propanoate] and (±)-DBZ [(±)-bornyl 2-hydroxy-3-(3,4-dihydroxyphenyl)propanoate]. Subsequent hydrogenation has been carried out by employing Raney Ni as catalyst. The improved process results in higher yields of 47.5% for (±)-DBZ and 49.2% for (±)-IDHP compared to the initial process with a yield of 12% for (±)-DBZ and 18% for (±)-IDHP in our original medicinal chemistry route. Furthermore, kilograms of optical DBZ [(−)-S-DBZ and (+)-R-DBZ, >99% ee] and IDHP [(−)-S-IDHP and (+)-R-IDHP, >99% ee] have been produced by chiral high-performance liquid chromatography in good yield (>84%).

A 50 m thick diabase sill was found in the Paleogene black mudstone hydrocarbon source rocks in Xia38 well. Within heating aureola of the sill, optical changes of kerogen and signatures of extractable bitumens in the mudstones were investigated. Under effects of high heating rate associated with sill intrusion, the vitrinite reflectance (Ro) has an increasing tendency with decreasing distance to the sill both below and above the sill. However, only within a zone of about 15 m to the diabase sill, the vitrinite reflectance shows significant increase. Above the sill, the Ro values increase gradually from 0.6% to 1.0%, whereas below the sill, the Ro values increase dramatically from 0.8% to 3.8%. The contrasting Ro increasing patterns are attributed to the different heat transferring conditions, the relatively open system above the sill and the relatively close system below. The more mature signatures below the sill are also demonstrated by the n -alkane distribution, carbon predominance index and odd-to-even carbon number predominance of the extracted bitumens. Below the sill, the proportion of the saturated hydrocarbons in the extracted bitumens increases from 34% to 79% towards the sill contact. The bitumens in the two highest rank samples which are closest to the sill are dominated by saturated or saturated + aromatic hydrocarbons. The %20S, %αββ and %Ts biomarker parameters of the extracted bitumens are 46%, 58% and 54%, respectively, at Ro = 1.5%. At Ro = 2.6% or 3.0%, they reach to 52%, 71%, and 71%, respectively, still under or close to their corresponding equilibrium end-points. These samples of high rank, established on the basis of optical assessment (vitrinite reflectance), have less mature biomarker signatures. The remarkable disparities between optical and biomarker parameters can be ascribed to that the aromatization of kerogen to increase Ro was more favored than the isomerization of biomarker in the rapid heating scenario.

The electrochemiluminescence (ECL) of the ruthenium di(2,2′-bipyridine)- (4,7-diphenyl-1,10-phenanthroline) complex (Ru-bipy-dpp) produced on a glassy carbon electrode was studied by cyclic voltammetry. The anodic oxidation of Ru-bipy-dpp produces ECL in the presence of oxalate in oxygen-free aqueous solutions. Threefold ECL efficiencies were obtained for Ru-bipy-dpp relative to Ru(bipy)3 as a standard. The ECL of Ru-bipy-dpp is quenched by both oxygen and phenol. The luminescence intensity was proportional to the concentration of phenol in the range of 5–100 µM. At a phenol concentration of 100 µM, the ECL of Ru-bipy-dpp peaking at 597 nm was completely quenched.

This study investigated the effect of hypoxia at high altitude on the semen quality and the serum reproductive hormone levels in male adults. A total of 52 male soldiers were enrolled in this cohort study. They were exposed to hypoxia at high altitude (5380 m) for 12 months when undergoing a service. After exposure, they were followed up for 6 months. The samples of semen and peripheral blood were collected at 1 month before exposure (M0), 6 months of exposure (M6), 12 months of exposure (M12), and 6 months after exposure (M18). The semen quality was assessed with computer-assisted analysis system, and the serum levels of reproductive hormones, including prolactin (PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone were analyzed by ELISA. Compared with those at M0, total sperm count, sperm density, motility, survival rate, and serum levels of LH, PRL and testosterone were significantly decreased, whereas the liquefaction time was significantly prolonged and serum FSH level was significantly increased at M6 (p

Although green fluorescence protein (GFP) and its antibody are widely used to track a protein or a cell in life sciences, the binding behavior between them remains unclear. In this work, diazo coupling method that synthesized a new stationary GFP was oriented immobilized on the surface of macro-porous silica gel by a phase. The stationary phase was utilized to confirm the validation of injection amount-dependent analysis in exploring protein-protein interaction that use GFP antibody as a probe. GFP antibody was proved to have one type of binding site on immobilized GFP. The number of binding site and association constant were calculated to be (6.41 ± 0.76) × 10(-10) M and (1.39 ± 0.12) × 10(9) M(-1). Further analysis by molecular docking showed that the binding of GFP to its antibody is mainly driven by hydrogen bonds and salt bridges. These results indicated that injection amount-dependent analysis is capable of exploring the protein-protein interactions with the advantages of ligand and time saving. It is a valuable methodology for the ligands, which are expensive or difficult to obtain.

A new mathematical model and frontal analysis were used to characterize the binding behavior of caffeic acid to human serum albumin (HSA) based on high-performance affinity chromatography. The experiments were carried out by injecting various mole amounts of the drug onto an immobilized HSA column. They indicated that caffeic acid has only one type of binding site to HSA on which the association constant was 2.75 × 10(4) /m. The number of the binding site involving the interaction between caffeic acid and HSA was 69 nm. The data obtained by the frontal analysis appeared to present the same results for both the association constant and the number of binding sites. This new model based on the relationship between the mole amounts of injection and capacity factors assists understanding of drug-protein interaction. The proposed model also has the advantages of ligand saving and rapid operation.

In this paper is used the rough set theory to deal with the information contained in electrocardiographic waveforms and to find out the correlation between coronary heart disease (CHD) and the selected indices in electrocardiographic lead I. The principles of attribute reduction are applied, the redundancy of a decision-making table is reduced, and the important characters and diagnostic rules are extracted. The real case analysis shows that clear and concise diagnostic rules can be established by using rough set theory, which can be helpful to the clinical diagnosis of CHD.

A new oriented method using a diazonium salt reaction was developed for linking β 2-adrenoceptor (β 2-AR) on the surface of macroporous silica gel. Stationary phase containing the immobilised receptor was used to investigate the interaction between β 2-AR and ephedrine plus pseudoephedrine by zonal elution. The isotherms of the two drugs best fit the Langmuir model. Only one type of binding site was found for ephedrine and pseudoephedrine targeting β 2-AR. At 37 °C, the association constants during the binding were (5.94±0.05)×103/M for ephedrine and (3.80±0.02) ×103/M for pseudoephedrine, with the binding sites of (8.92±0.06) ×10−4 M. Thermodynamic studies showed that the binding of the two compounds to β 2-AR was a spontaneous reaction with exothermal processes. The ΔGθ, ΔHθ and ΔSθ for the interaction between ephedrine and β 2-AR were −(22.33±0.04) kJ/mol, −(6.51±0.69) kJ/mol and 50.94±0.31 J/mol·K, respectively. For the binding of pseudoephedrine to the receptor, these values were −(21.17±0.02) kJ/mol, −(7.48±0.56) kJ/mol and 44.13±0.01 J/mol·K. Electrostatic interaction proved to be the driving force during the binding of the two drugs to β 2-AR. The proposed immobilised method will have great potential for attaching protein to solid substrates and realizing the interactions between proteins and drugs.