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Lycopene is an important carotenoid which has been widely used as functional foods and feed supplements, and pharmaceutical compounds. In the present study, the host strain and the auxiliary carbon source were optimized to enhance the lycopene yield in the recombinant Escherichia coli. The results showed that lycopene concentration of the cells could be significantly increased when the recombinant strain was grown on the LB medium supplemented with 6 g l−1 fructose, whereas glucose has little effect. Under the optimized conditions, the recombinant bacteria could exhibited a lycopene yield up to 1,050 mg l−1 for 24 h in a 250 ml baffled flask. This is the first report of enhancing lycopene production by supplementing with fructose.

A novel xylanase of family 11 (Xyn11-1) was obtained from the metagenomic DNA of alkaline soil by touchdown-PCR and thermal asymmetric interlaced (TAIL) PCR methods. Xyn11-1 is composed of 645 nucleotides, which encodes a signal peptide of 19 amino acids and a mature protein of 196 amino acids. It is a novel GH11 xylanase sharing the highest identity (79 %) with the reported GH11 xylanase (XP_008721536) in GenBank database. In order to detect its biological activity, the recombinant plasmid xyn11-1-pET28a(+) was constructed and recombinant protein was successfully expressed in heterologous hosts Escherichia coli BL21 (DE3) induced by isopropy-beta-d-thiogalactopyranoside (IPTG). Using the 3,5-dinitrosalicylic acid (DNS) method, the xylanase activity of crude intracellular protein is 11.32 U/mL. The optimal inducing IPTG concentration and inducing temperature was examined at 0.2 mM and 15 °C, respectively.

The exposure to static magnetic fields (SMFs) has rapidly increased and is recently accompanied with the wide use of more and more electrical appliances. Although few researches have been reported on other types of magnetic fields that may have the effects on clinical therapy of diseases, it is rarely seen reports on the effects of moderate static magnetic fields on human health. In this study, in order to evaluate the influence of exposure to moderate static magnetic fields on biological systems, we cultured the INS-1 under exposure to moderate intensity of 400 mT and sham conditions for different times from 6 to 18 h, insulin secretion to medium and mRNA expression will be tested after exposure. Insulin secretion has significantly increased after exposed to SMFs with moderate intensity of 400 mT for 18 h compared with the sham condition. Furthermore, similar to the insulin secretion, insulin 1 and insulin 2 mRNA expression also increased after exposure. These results suggest that exposure to SMFs at 400 mT position for specific times might have positive stimulation in both insulin secretion and insulin mRNA expression, and these will be used hopefully in further investigations in vitro, even in the therapy clinically.

Protein S-nitrosylation is a type of posttranslational modification that changes protein stability, intracellular localization, and biological activity. In mammalian cells, NO is synthesized by NOS which is highly expressed in many solid tumors, including breast cancer. NOS is involved in the progress of carcinogenesis by generating NO to modify various tumor-related proteins to enhance or suppress their function. However, the effect of NO on tumor metastasis is less studied. Herein, breast cancer cells MCF-7 and MDA-MB-231 were treated with NO donor SNP, which resulted in altered cell mobility. Meanwhile the expression of several metastasis-related genes was regulated. These results suggest a novel mechanism by which NO promotes the metastasis of breast cancer.

Glucagon-like peptide-1 (GLP-1) is an incretin, which can effectively lower blood glucose levels, increase insulin secretion, and improve insulin sensitivity in patients with diabetes. Therefore, it is a potent endogenous insulin-stimulating hormone. Unfortunately, since GLP-1 can be degraded by the enzyme DPP-IV and NEP 24.11, its therapeutic benefit and fermentation yield are limited by the instability. Previous study has shown that replacement of the Lys34 with Arg could enhance the stability of GLP-1 in the plasma. In this study, to further improve the stability of the GLP-1, an additional mutation, replacement of Phe28 by Ser, was constructed, and then the protein was expressed in the recombinant Pichia pastoris, and analyzed by HPLC. The results show that this mutation could improve the stability of GLP-1 during fermentation.

L-tert-Leucine is an unnatural amino acid that is a key intermediate for the synthesis of several important drugs. The L-tert-Leucine synthesis can be performed continuously by the collaboration of leucine dehydrogenase and formate dehydrogenase. In this study, recombinant strains of Escherichia coli expressing leucine dehydrogenase (LeuDH) and formate dehydrogenase (FDH), respectively, and the strain co-expressing the two enzymes were constructed. The activity for the two enzymes of the cell extraction from different recombinant strains was determined. L-tert-Leucine was successfully synthesized by the recombinant strains, and the yield in different conditions was compared. The production of L-tert-Leucine was the highest when cell extraction of strains containing pLeuDH and pFDH, 1 mL cells extract could produce 4.5 mg L-tert-Leucine, while 1 mL whole cells could only produce 1.05 mg L-tert-Leucine. The yield of L-tert-Leucine was 3.375 mg/mL cell extraction of the strain containing pLeuDHFDH when NAD was added, while the yield fell to 1.635 mg/mL when the whole cell was used.

Pu’er Tea is a popular post-fermented tea and has a variety of health benefits. Many microorganisms, especially lactobacillus, exist and play an important role in the fermentation process of Pu’er tea. In this study, we try to screen some lactobacillus by plate method from the Pu’er tea, and strain C2 with significant cycle isolated from Pu’er tea. 16S rRNA gene sequencing results showed that strain C2 had 99 % sequence similarity to that of the type strain of three Bacillus coagulans (NR 102791.1, CP002472.1, NR 115727.1), and the results show that methyl red test and V&P test were positive. Sugar fermentation test suggested that strain C2 produced acid but not gas, which is identical to B. coagulans. This study confirmed that lactic acid bacteria play a role in Pu’er tea fermentation.

In eukaryotic cells, maintenance of genomic stability relies on the coordinated action of a network of cellular processes, including DNA replication, DNA repair, cell-cycle progression, and others. The DNA damage response (DDR) signaling pathway mediated by the ataxia telangiectasia-mutated (ATM) and ATM and Rad3-related (ATR) kinases is the central regulator of this network in response to DNA damage. The serine/threonine kinases ATM and ATR are the main kinases activated following various assaults on DNA. In this study, human ATM and ATR promoter luciferase reporter constructs were generated by PCR amplification. Then both PCR fragments respectively were digested and cloned into pGL3 vector. Finally, these promoter sequences were verified by sequencing. These results showed that luciferase reporter with ATM and ATR promoters were successfully constructed. Then the activation of the ATM promoter and ATR promoter following UV light treatments were detected in A431 cells by luciferase reporter assays. The results showed that UV damage could enhance transcriptional activity of ATM/ATR. Our research will provide useful tools for further deciphering ATM/ATR signaling and the pathways mediating the DNA damage response.

Human epidermal growth factor (hEGF), a well-known polypeptide agent which has been widely used in the medicine and cosmetics, is a 6.2 kDa single-chain polypeptide consisting of 53 amino acids. Here, to enhance its transmembrane ability, a recombinant EGF fused with Pep-1, a cell-penetrating peptides (CPP) that has been previously shown to be powerful transport vector tool for the intracellular delivery of a variety of cargos through the cell membrane, was expressed in Escherichia coli. Furthermore, The expression conditions was optimized, and the results showed that the Pep-1-fused EGF (P-EGF) could be successfully expressed in E. coli BL21-TrixB (DE3) using an expression vector, pGEX-6P-3, which contains a GST tag. The recombinant product reached the highest soluble expression when the expression strain was induced by 0.2 mmol/l IPTG and cultivated at the temperature of 20 °C with a rotation speed of 200 rpm for 8 h.

Lycopene, as a red-colored intermediate of the β-carotene biosynthetic pathway, has attracted considerable attention due to its beneficial role in human health. And it is a potent antioxidant and of much bioactivity such as quenching singlet oxygen and scavenging free radicals, resulting in protection against oxidative DNA damage in vitro and in vivo. In this review we hope to concisely describe the nature of lycopene compounds, the scientific basis for its proposed anti cancer and cardiovascular protection properties and focus on discussion of such advances in microbial production of lycopene by fermentation.

Cancer is one of the major causes of death worldwide. Many clinical evidences showed that the incidence of colon cancer increased after the cholecystectomy, suggesting that bile acid and its derivatives might play roles in the process of tumorigenesis and its prevention. Bile acid derivative is a kind of good candidates for prodrug design, but there are still few reports of its development for anticancer drugs either domestically or internationally. In the present study, IC50 of 9 bile acid derivatives against MCF-7 human breast cancer cells was detected by MTT assay, and the safety of several bile acid derivatives with high anticancer effect were further analyzed in human umbilical vein endothelial cells. The results showed that among 9 bile acid derivatives, cholic acid n-buthyl ester had lower IC50 against cancer cells, but it did not have cytotoxicity to normal cell at low concentration, indicating that they would be a good candidate for the development of novel anticancer agents.

In this paper, we focus on the effects of dual-frequency ultrasound (40 and 80 kHz) with α-amylases (5U/g) on the properties and structure of mung bean starch. The reducing sugar value and starch solubility in the treated starch slurry under ultrasound enzyme were studied. Scanning electron microscopy (SEM) and Fourier transform infrared spectrometer (FTIR) were used to measure the apparent structure and crystal texture of starch. The results indicated that compared with the results of single-frequency ultrasound treatment, dual-frequency ultrasound promoted the starch hydrolysis by amylase and increased the starch solubility remarkably. More channels and holes were found on the surface of treated starch granule by SEM. The results of FTIR analysis showed the FTIR peak shape of ultrasonic treated starch was different from that of the control starch.

MicroRNAs (miRNAs) are small noncoding RNAs with regulatory functions, which play an important role in malignancies. An increasing amount of experimental evidence has shown that many miRNAs are aberrantly expressed in breast cancer and influence breast cancer behavior and progression. Furthermore, miRNAs can act either as tumor suppressors or as oncogenes, depending on the targets they regulate, and measurements of miRNAs expression in breast cancer have diagnostic and prognostic implications. Thus, this implies that miRNAs have huge potential as biomarkers. In addition, their extreme stability and ease of detection further support the idea that miRNAs have great potential to evolve into effective biomarkers in the clinic. The objective of this review is to update current realization regarding that miRNAs are promising candidates at diagnostic, therapeutic and prognostic evaluation aspects of clinical application.

Breast cancer, a hormone-dependence disease, is the most common malignant tumor in women. Breast cancer incidence rates increase with age. Telomerase is a ribonucleoprotein that maintains chromosome ends and endows cells with unlimited proliferative potential. Activation of telomerase maintains a relatively stable telomere length, confers immortality on some cells, and may even lead to cancer. It has been reported that, in the tissues of the breast, the activity of telomerase can be detected in more than 90 % of invasive breast cancers, while not in adjacent normal tissues. Thus, telomerase activation plays a critical role in development of breast cancer. Telomerase has been proposed as a biomarker with diagnostic and prognostic potential in breast cancer as well as a basis for the targeted therapy of breast cancer.

Biological treatment is one of the considerable choices for removing of organic pollutants present in petrochemical wastewaters. In this study, five strains, named as BS1, BS2, BS3, BS4 and BS5, were isolated from sludge nearby a petroleum smelter. BS5, the isolate with the highest COD removal rate, was identified as Bacillus flexus, based on 16S rDNA sequences. Subsequently, the optimized COD removal conditions of BS5 were investigated. It was indicated that the optimal conditions were 0.5 % corn starch, 1 % corn steep liquor, 35 C, pH 7.5, and 10 % (v:v) inoculation size. Under such circumstance, the removal rate of COD can reach 81.04 %. The isolation of Bacillus flexus strain BS5 provided an alternative for the bioremediation of alkaline wastewater. Lastly, the study showed that consecutive disposal process may help to reducing COD of wastewater effectively.

Myocardin-related transcription factor A (MRTF-A) is a transcriptional coactivator of serum response factor (SRF). Recent studies have found that the MRTF–SRF signal pathway might play critical role in Rho-dependent cytoskeletal rearrangements and tumor metastasis. To further explore the detailed molecular mechanisms for MRTF-A-mediated cell migration, in this study, the effect of MRTF-A on the migration of mouse fibroblast NIH3T3 cells and MCF-7 human breast cancer cells was detected using a scratch wound model, and its transcriptional activity on the promoter of Cysteine-rich angiogenic inducer 61 (CYR61) was also analyzed by luciferase assay. The results showed that overexpression of MRTF-A could significantly promote the migration of NIH3T3 cells and drive the transcriptional activity of CYR61 promoter in African green monkey kidney COS-7 cells and strongly enhance upregulation of CYR61 gene. In contrast, RNA interference-mediated knockdown of MRTF-A reduced the migration ability of MCF-7 breast cancer cells. Taken together, our results suggested that MRTF-A is involved in tumor metastasis via transactivation of CYR61.

Objective: Monitoring data of patients with essential hypertension associated with impaired glucose tolerance then provide clinical basis for the intervention of diabetes and reduce cardiovascular and cerebrovascular disease risk factors. Method: Select 158 patients without sugar metabolic abnormalities previously, whose fasting plasma glucose is

MicroRNAs are small non-coding RNAs with 19-22 nucleotides. MiR-124 expresses abundantly in brain tissue and is involved in the development of ischemic cerebrovascular disease (ICVD). Tumor necrosis factor-alpha (TNF-α) is one of the important factors of the inflammatory reaction after cerebral ischemia. To explore the roles of miR-124 and TNF-α in the process of ICVD, here, we collected the serum of 15 patients with ICVD and 5 normal individuals. The levels of miR-124 and TNF-α were detected by real-time PCR and ELISA. The results showed that compared with the normal individuals, the levels of miR-124 and TNF-α in serum were upregulated in the patients, while they were downregulated after clinical treatment, suggesting that these two factors could be used as good biomarkers for the diagnosis and prognosis of ICVD. Besides, our research also provided a theory foundation for understanding the mechanism of inflammatory response in cerebral ischemia mediated by miR-124.

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease leading to synovial hyperplasia and a series of multisystem comorbidities. Permanent disability usually occurs in 20–30 % of untreated patients within 2–3 years of the disease. Therefore, it is important to diagnose the disease and initiate treatment as early as possible. The drug therapy plays an important role in maintaining a state of very low disease activity and slowing the progression of joint damage. Traditional drug therapy in RA is a pyramid approach, in which nonsteroidal anti-inflammatory drugs (NSAIDs) serve as the base of pyramid and disease-modifying antirheumatic drugs (DMARDs) are employed relatively late. But since this approach is no longer valid, many new drugs used to manage RA have been developed. In this review, we specifically summarize the current drug therapies for the treatment of RA and briefly describe the etiology, pathology and pathogenesis of RA.

This paper described a combined high-performance liquid chromatography (HPLC) -photochemical spectrofluorimetry/solid-phase extraction (SPE) procedure for determining the concentration of unmetabolized folic acid in human serum. After being extracted by SPE (C18-H) column, the serum samples were irradiated under the UV lamp for 11 h, separated on a C18 HPLC column with methanol/water as the mobile phases and determined by a fluorescence detector. Fluorescence excitation and emission wavelengths were at 280 and 443 nm, respectively. The linear range was 1.9 ~ 8.0 ng/mL. The recovery was from 88.9 to 123.6 % with RSD in the range of 4.1–6.4 %.

Gambogic acid (GA) shows important biological activities for carcinoma cells, such as selectively inducing apoptosis and differentiation, inhibiting proliferation and transference, inversing multiple drug resistance (MDR). However, its aqueous solubility is so low that its oral bioavailability is not as good as those marketed antitumor chemical drugs. In this paper, two GA derivatives with better aqueous solubility were designed and prepared. Among them N,N-bis-(β-hydroxyethyl) GA carboxamide was synthesized by DCC-HOBt catalyzed coupling reaction between GA and diethanolamine, and monoester of succinic acid by GA esterification with methyl succinyl chloride followed by mild hydrolysis with lithium hydroxide. The structures of these two target compounds and one intermediate were characterized by ESI–MS and 1H NMR spectra after their purification. These studies are of great significance for us to develop GA chemical entities with effective potency to treat cancers.

In a number of pathological conditions such as hypertension, valvular disease, myocardial infarction, and cardiomyopathy, postnatal cardiomyocytes undergo cardiac hypertrophy. Cardiac hypertrophy is the heart’s response to increased biomechanical stress, which is accompanied by activation of a fetal gene program, assembly of sarcomeres, and cellular enlargement. Prolonged hypertrophy is a major predictor of heart failure and sudden death. Identification of the signaling molecules is necessary for the development of therapeutic strategies to prevent or reverse the disease. Recent researches have found that there were different signaling pathways activated in cardiac hypertrophy, but the molecular mechanism of cardiac hypertrophy is not completely elucidated so far. In this review, we summarize recent insights into hypertrophic signaling pathways.

Betulin and betulinic acid are natural product with antitumor and anti-HIV-1 activity. Betulin can be got by chemical extraction from a lot of plants. Betulinic acid can be synthesized from betulin. In order to get high biological activity compounds with antitumor and anti-HIV-1 activity from the bark of the white birch, the extraction and purification method of betulin was studied; the optimized extraction and purification condition was obtained. The two-step synthetic routes of betulinic acid from betulin were discussed. Betulinic acid was synthesized by oxidizing betulin with Jones reagent, followed by selective reduction with NaBH4. IR, HPLC–MS, H1-NMR were used to identify the structure of betulin and betulinic acid.

Mesenchymal stem cells (MSCs) are pluripotent progenitors and can differentiate into a variety of cell types, including osteoblasts, chondrocytes, and adipocytes. Vascular endothelial growth factor (VEGF) has been shown to stimulate endothelial cell mitogenesis and migrations. To investigate whether VEGF could induce rat bone marrow-derived MSCs differentiation into endothelial cells, we isolated and cultured rat bone marrow-derived MSCs from the femur of the Sprague–Dawley rats. MSCs were treated with VEGF for 2, 4, 7 days. The cellular morphology changes of MSCs were observed under phase contrast microscope. Then we tested the expression of endothelial cell markers VEGF receptor fms-related tyrosine kinase 1 (Flt-1) by reverse-transcription PCR (RT-PCR), western blot, and immunofluorescence technology. Our results showed that the expression levels of Flt-1 were significantly increased in time-dependent manner. The above results show that VEGF can induce mesenchymal stem cells differentiation into endothelial cells. The data provides the basis of constructing tissue engineering vascular.

Lactobacillus plantarum (L. plantarum) is a flexible and versatile microorganism that inhabits a variety of environmental niches, and some strains are marketed as probiotics. In this study, a strainTH1 which was isolated from silage in our former works was classified asL. plantarum by 16S rDNA sequence analysis and phylogenetic tree. Then its potential abilities of bile tolerance, nitrate reduction and anti-hypertension were investigated. The results showed that L. plantarum TH1 had capacity to resistance to bile salt, directly deoxygenate nitrate to nitrogen or ammonia rather then nitrite, and produce ACE inhibitory components in fermented milk. These works indicated that this novel lactobacillus strain might be considered as candidates for probiotics strains using in the food or drug system to improve the health of patients suffering from hypertension or other chronic disease.