Decrease in SHP-1 enhances myometrium remodeling via FAK activation leading to labor.

Preterm birth is one of the most common complications during human pregnancy and is associated with a dramatic switch within the uterus from quiescence to contractility. However, the mechanisms underlying uterine remodeling are largely unknown. Protein kinases and phosphatases play critical roles in regulating the phosphorylation of proteins involved in the smooth muscle cell functions. In the present study, we found that Src-homology phosphatase type-1 (SHP-1, PTPN6) was significantly decreased in human myometrium in labor compared with that not in labor. Timed-pregnant mice injected intraperitoneally with the specific SHP-1 inhibitor protein tyrosine phosphatase inhibitor I (PTPI-1) manifested significantly preterm labor, with enriched plasmalemmal dense plaques between myometrial cells and increased phosphorylation at Tyr397 and Tyr576/577 sites of focal adhesion kinase (FAK) in myometrial cells, which remained to the time of labor, whereas the phosphorylation levels of ERK1/2 and phosphatidylinositol 3 kinase (PI3K) showed a rapid increase upon PTPI-1 injection but fell back to normal at the time of labor. The Tyr576/577 in FAK played an important role in the interaction between FAK and SHP-1. Knockdown of SHP-1 dramatically increased the spontaneous contraction of human uterine smooth muscle cells (HUSMCs), which was reversed by coinfection of a FAK-knockdown lentivirus. PGF2α downregulated SHP-1 via PLCß-PKC-NF-κB or PI3K-NF-κB pathways, suggesting the regenerative downregulation of SHP-1 enhances the uterine remodeling and plasticity by activating FAK and subsequent focal adhesion pathway, which eventually facilitates myometrium contraction and leads to labor. The study sheds new light on understanding of mechanisms that underlie the initiation of labor, and interventions for modulation of SHP-1 may provide a potential strategy for preventing preterm birth.

Prostaglandin E2 receptors differentially regulate the output of proinflammatory cytokines in myometrial cells from term pregnant women.

Prostaglandin (PG) E2 plays critical roles during pregnancy and parturition. Emerging evidence indicates that human labour is an inflammatory event. We sought to investigate the effect of PGE2 on the output of proinflammatory cytokines in cultured human uterine smooth muscle cells (HUSMCs) from term pregnant women and elucidate the role of subtypes of PGE2 receptors (EP1, EP2, EP3 and EP4). After drug treatment and/or transfection of each receptor siRNA, the concentrations of inflammatory secreting factors in HUSMCs culture medium were detected by the corresponding ELISA kits. The results showed that, PGE2 increased interleukin 6 (IL-6) and tumor necrosis factor alpha (TNFα) output, decreased chemokine (c-x-c motif) ligand 8 (CXCL8) output in a dose-dependent manner, but had no effect on IL-1ß and chemokine (c-c motif) ligand 2 (CCL-2) secretion of HUSMCs. EP1/EP3 agonist 17-phenyl-trinor-PGE2 stimulated IL-6 and TNFα whilst suppressing IL-1ß and CXCL8 output. The effects of 17-phenyl-trinor-PGE2 on IL-1ß and CXCL8 secretion were remained whereas its effect on IL-6 and TNFα output did not occur in the cells with EP3 knockdown. The stimulatory effects of 17-phenyl-trinor-PGE2 on IL-6 and TNFα were remained whereas the inhibitory effects of 17-phenyl-trinor-PGE2 on IL-1ß secretion was blocked in the cells with EP1 knockdown. Either of EP2 and EP4 agonists stimulated IL-1ß and TNFα output, which was reversed by EP2 and EP4 siRNA, respectively. The inhibitors of phospholipase C (PLC) and protein kinase C (PKC) blocked EP1/EP3 modulation of TNFα and CXCL8 output. PI3K inhibitor LY294002 and P38 inhibitor SB202190 blocked 17-phenyl-trinor-PGE2-induced IL-1ß and IL-6 output, respectively. The inhibitors of adenylyl cyclase and PKA prevented EP2 and EP4 stimulation of IL-1ß and TNFα output, whereas PLC and PKC inhibitors blocked EP2- and EP4-induced TNFα output but not IL-1ß output. Our data suggest that PGE2 receptors exhibit different effects on the output of various cytokines in myometrium, which can subtly modulate the inflammatory microenvironment in myometrium during pregnancy.

Reciprocal Feedback Between miR-181a and E2/ERα in Myometrium Enhances Inflammation Leading to Labor.

CONTEXT: The initiation of term and preterm labor is associated with an up-regulated inflammatory response in myometrium; however, the underlying signaling pathways remain incompletely defined. OBJECTIVE: To define the regulatory mechanisms that mediate the increased myometrial inflammatory response leading to labor, we investigated the roles of microRNAs (miRNA/miR). DESIGN AND SETTING: Human myometrial tissues, isolated smooth muscle cells, and animal models were used to study miR-181a regulation of uterine inflammatory pathways and contractility. PATIENTS: Myometrial tissues from 15 term pregnant women undergoing elective cesarean section (not in labor) and 10 term pregnant women undergoing emergency cesarean section (in labor) were used. RESULTS: Expression of the highly conserved microRNA, miR-181a, was significantly decreased in mouse and human myometrium during late gestation. By contrast, the putative miR-181a targets, TNF-α, and estrogen receptor (ER)-α, and the validated target, c-Fos, key factors in the inflammatory response leading to parturition, were coordinately up-regulated. In studies using human myometrial cells, overexpression of miR-181a mimics repressed basal as well as IL-1ß-induced TNF-α, C-C motif chemokine ligand 2 and 8 expression, whereas the expression of the antiinflammatory cytokine, IL-10, was increased. Overexpression of miR-181a dramatically inhibited both spontaneous and IL-1ß-induced contraction of human myometrial cells. Notably, miR-181a directly targeted ERα and decreased its expression, whereas estradiol-17ß reciprocally inhibited expression of mature miR-181a in myometrial cells. CONCLUSIONS: Thus, increased estradiol-17ß/ERα signaling in myometrium near term inhibits miR-181a, resulting in a further increase in ERα and proinflammatory signaling. This escalating feedback loop provides novel targets and therapeutic strategies for the prevention of preterm labor and its consequences.

Hollow graphitic nanocapsules as efficient electrode materials for sensitive hydrogen peroxide detection.

Carbon nanomaterials are typically used in electrochemical biosensing applications for their unique properties. We report a hollow graphitic nanocapsule (HGN) utilized as an efficient electrode material for sensitive hydrogen peroxide detection. Methylene blue (MB) molecules could be efficiently adsorbed on the HGN surfaces, and this adsorption capability remained very stable under different pH regimes. HGNs were used as three-dimensional matrices for coimmobilization of MB electron mediators and horseradish peroxidase (HRP) to build an HGN-HRP-MB reagentless amperometric sensing platform to detect hydrogen peroxide. This simple HGN-HRP-MB complex demonstrated very sensitive and selective hydrogen peroxide detection capability, as well as high reproducibility and stability. The HGNs could also be utilized as matrices for immobilization of other enzymes, proteins or small molecules and for different biomedical applications.

[Study on environmental and psychological risk factors for female infertility].

OBJECTIVE: To investigate the environmental and psychological risk factors for female infertility and to provide a scientific basis for the prevention and control of female infertility. METHODS: In a hospital-based case-control study, a self-designed questionnaire was used to survey the cases and controls (1:1) with nation and age (± 2 years) as matching variables. Univariate and multivariate conditional logistic regression models were employed to analyze the datasets. RESULTS: The univariate analysis showed that female infertility was related to the following factors: eating fried foods, alcohol consumption, smoking, staying up late, perm, housing decoration, contact with heavy metals, exposure to radiation, contact with pesticides, working in hot environment, mental stress, uneasiness, helplessness, and despair. The multivariate analysis showed that staying up late (OR = 2.937), housing decoration (OR = 2.963), exposure to radiation (OR = 2.506), contact with pesticides (OR = 2.908), and mental stress (OR = 4.101) were the main risk factors for female infertility. Furthermore, there was an interaction between staying up late and mental stress. CONCLUSION: Female infertility is caused by multiple factors including staying up late, housing decoration, exposure to radiation, contact with pesticides, and mental stress, and there is an interaction between staying up late and mental stress.

Fluorosurfactant-capped gold nanoparticles-based label-free colorimetric assay for Au³âº with tunable dynamic range via a redox strategy.

Gold nanoparticles-based colorimetric assay possesses several unique advantages, and has been applied for a wide range of targets, varying from nucleic acids to different metal ions. However, due to the lack of proper coordinating ligand, gold nanoparticles-based colorimetric sensing system for Au³âº has not been developed so far. It is well-known that Au³âº could induce the oxidation transition of thiol compounds to disulfide compounds. In this article, for the first time we converted such thiol masking reaction into colorimetric sensing system for label-free detection of Au³âº via a target-controlled aggregation of nanoparticles strategy. In the new proposed sensing system, fluorosurfactant-capped gold nanoparticles were chosen as signal reporter units, while an Au³âº-triggered oxidation of cysteine (Cys), which inhibited the aggregation of gold nanoparticles, acted as the recognition unit. By varying the amount of Cys, a tunable response range accompanied with different windows of color change could be obtained for Au³âº, illustrating the universality of the sensing system for Au³âº samples with different sensitivity requirements. Under optimized condition, the proposed sensing system exhibits a high sensitivity towards Au³âº with a detection limit of 50 nM, which is lower than previously reported spectroscopic methods. It has also been applied for detection of Au³âº in practical water samples with satisfactory result.

Magnetic graphitic nanocapsules for programmed DNA fishing and detection.

Graphene nanomaterials are typically used in biosensing applications, and they have been demonstrated as good fluorescence quenchers. While many conventional amplification platforms are available, developing new nanomaterials and establishing simple, enzyme-free and low-cost strategies for high sensitivity biosensing is still challenging. Therefore, in this work, a core-shell magnetic graphitic nanocapsule (MGN) material is synthesized and its capabilities for the detection of biomolecules are investigated. MGN combines the unique properties of graphene and magnetic particles into one simple and sensitive biosensing platform, which quenches around 98% of the dye fluorescence within minutes. Based on a programmed multipurpose DNA capturing and releasing strategy, the MGN sensing platform demonstrates an outstanding capacity to fish, enrich, and detect DNA. Target DNA molecules as low as 50 pM could be detected, which is 3-fold lower than the limit of detection commonly achieved by carbon nanotube and graphene-based fluorescent biosensors. Moreover, the MGN platform exhibits good sensing specificity against DNA mismatch tests. Overall, therefore, these magnetic graphitic nanocapsules demonstrate a promising tool for molecular disease diagnosis and biomedicine. This simple fishing and enrichment strategy may also be extended to other biological and environmental applications and systems.

[Exploration of the association of H. pylori and EBV infection with cardiac and distal gastric adenocarcinoma among residents in Cixian County, a high-risk area of esophgeal cancer in Hebei province].

OBJECTIVE: To evaluate the H. pylori and Epstein-Barr virus infection in cardiac and distal gastric adenocarcinoma tissues in residents in Cixian county, a high risk area of esophageal cancer in Hebei province, and to explore the putative role of H. pylori and Epstein-Barr virus infection in the carcinogenesis of adenocarcinoma at different subsites of stomach. METHODS: H. pylori and Epstein-Barr virus latent membrane protein 1 (EBV-LMP1) immunopositivities were determined by Elivision(TM) plus immunohistochemical staining in 190 gastric adenocarcinoma tissues including 144 cases of cardiac adenocarcinoma and 46 cases of distal gastric adenocarcinoma. The relationship between H. pylori and Epstein-Barr virus infection and the subsite, Laurén type as well as other clinicopathological features of gastric adenocarcinoma were analyzed. RESULTS: No significant difference was found between the H. pylori detection rates in cardiac and distal gastric adenocarcinomas(56.9% vs. 65.2%, P > 0.05). The detection rate of H. pylori in intestinal type was significantly higher than that in the diffuse type distal gastric adenocarcinomas (71.8% vs. 28.6%, P < 0.05). No positive expression of EBV-LMP1 was found in the gastric adenocarcinomas in this study. CONCLUSIONS: No significant differences in H. pylori and EBV-LMP1 infections were found between cardiac and distal gastric adenocarcinomas in Cixian county. H. pylori infection is related with the intestinal type of distal gastric adenocarcinoma.

Cloning of the surface layer gene sllB from Bacillus sphaericus ATCC 14577 and its heterologous expression and purification.

A cDNA fragment encoding the S-layer protein SllB cloned from Bacillus sphaericus ATCC 14577 was expressed on the surface of E. coli BL21 (DE3) cells and confirmed by the square lattice structure at the nanoscale level. The amplified gene fragment designed with PCR primers from a specified reference sequence (GenBank accession no. AJ849550) showed a high degree of sequence identity with the known sequences for S-layer protein. The best alignment scores were seen in B. sphaericus strains JG-A12 and NCTC9602, which code for a pre-form protein with a predicted cleavage site located between the two alanine residues 31 and 32. After this signal peptide sequence was removed, the mature protein had a molecular mass of 116.2613 kDa and a theoretical pI of 5.40. Further bioinformatic analysis revealed three S-layer homology (SLH) domains in the N-terminus of the mature protein, positioned at the 1-61, 63-128 and 137-197 residues. The mature S-layer protein was composed of alpha helices (24.86%), extended strands (27.01%), and rich random coils (48.13%). Bioinformatics-driven characterization of SllB may provide scientific evidence for further application of this gene in the fields of nanobiotechnology and biomimetics in the future.

Graphene-DNAzyme based biosensor for amplified fluorescence "turn-on" detection of Pb2+ with a high selectivity.

On the basis of the remarkable difference in affinity of graphene (GO) with ssDNA containing a different number of bases in length, we for the first time report a GO-DNAzyme based biosensor for amplified fluorescence "turn-on" detection of Pb(2+). A FAM-labeled DNAzyme-substrate hybrid acted as both a molecular recognition module and signal reporter and GO as a superquencher. By taking advantage of the super fluorescence quenching efficiency of GO, our proposed biosensor exhibits a high sensitivity toward the target with a detection limit of 300 pM for Pb(2+), which is lower than previously reported for catalytic beacons. Moreover, with the choice of a classic Pb(2+)-dependent GR-5 DNAzyme instead of 8-17 DNAzyme as the catalytic unit, the newly designed sensing system also shows an obviously improved selectivity than previously reported methods. Moreover, the sensing system was used for the determination of Pb(2+) in river water samples with satisfying results.

[Quantitative analysis of steroidal saponins in Chinese material medica Rhizoma Paridis by HPLC-ELSD].

OBJECTIVE: The several species of the genus Paris called as Rhizoma Paridis were famous traditional Chinese medica. To develop the quantitative analysis method of the steroidal saponins in some species of the genus Paris and commercially available Rhizoma Paridis samples by HPLC-ELSD. METHOD: The contents of 11 steroidal saponins in Rhizoma Paridis samples were dectected with a Kromasil C18(4.6 mm x 150 mm, 5 microm) column which was deluted with acetonitrile-water (30:70-60:40) at a flow rate of 1 mL x min(-1) by HPLC-ELSD. RESULT: All the authentic samples could be separated and calibration curves of 11 saponins were prepared. 11 steroidal saponins in 16 Rhizoma Paridis samples were detected in 30 min. The recovery for the assay of saponins was between 95% and 97%. The precision and stability of samples (RSD) were below 3%. CONCLUSION: The method was shown to be accurate and convenient, and suitable for the quantitative analysis of these 11 steroidal saponins in the commercially available Rhizoma Paridis samples.

[Study on pharmacokinetics of emodin in Rhizoma Polygontum Cuspidatum and its compound].

OBJECTIVE: To study the difference in the pharmacokinetics of emodin in Zhiganning capsules and Rhizoma Polygontum Cuspidatum by nonaqueous RP-HPLC. METHOD: The rats were orally administered with the extraction of Rhizoma Polygontum Cuspidatum and Zhiganning capsules. After hydrolysis and extraction, the content of emodin in the plasma is determined by Nonaqueous RP-HPLC. RESULT: The concentration-time profiles of emodin fit two-compartment model. The pharmacokinetics parameters including, t1/2alpha, AUC(0-infinity), CL(s) and C(max) of emodin in the group of Rhizoma Polygontum Cuspidatum were significantly different from these in the group of its compounds. CONCLUSION: There is a significant difference in pharmacokinetics of emodin between zhiganning capsules and the extraction of Rhizoma Polygontum Cuspidatum.