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Corpus luteum,an important endocrine tissue in mammalian ovary,plays a role in the regulation of reproductive cycle and the establishment of early pregnancy.While studying the luteal development and its molecular regulation,we have discovered a variety of immune cells,such as T lymphocytes,macrophages,neutrophils,and eosinophils,in the corpus luteum.These immune cells accumulate and support luteal angiogenesis and progesterone production during the luteal development,thus participating in the regulation of luteal functions.In luteal regression,prostaglandin F2 can stimulate the production of inflammatory cytokines and chemokines,which help immune cells enter the corpus luteum and enhance the decomposition of corpus luteum through inflammatory reactions.According to our research achievements,we reviewed the roles of different types of immune cells in the development and degradation of mammalian luteal functions,aiming to further understand the biology of corpus luteum and provide a reference for the clinical manipulation of luteal functions.

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For preventing widespread transmission of communicable diseases, we developed a simple method for detecting the presence of pathogens in human blood specimens quickly at the point of care, using Yersinia pestis, the bacteria for plague, as our first target. We addressed the disadvantage of the currently prevalent detection methods, which required the specimens to be transported to labs for microbial culture and analysis. Our system was highly sensitive, achieving 100 CFU/mL limit of detection with a linearity range between 102–107 CFU/mL. It was based on adding the specimens onto our in-house one-dimensional diffraction grating (ODG) chips, pointing laser beams at them at 45-degree incident angle, and measuring the intensity of the reflective diffraction, which would be reduced at the pathogen’s presence. The ODGs featured poly(methacrylic acid) (PMAA) brushes with the antibody at the tips to specifically capture the target pathogen but not other cells or pathogens. The laser beam entered the chips, which were oriented such that its trenches were parallel to the beam’s projection onto the chip plane as we found the system more sensitive in such configuration. The two- and three-dimensional reflective diffraction was characteristic in that the diffraction orders’ angles and amplitudes exhibited symmetric and asymmetric properties depending on the orientation of the chips. Their intensity was an indicator for the presence of specific pathogen. The instruments were portable, and the entire process could be completed at the point of care within minutes.

Plague is a disease infected by an etiological agent, which is transmitted from fleas to a variety of wildlife rodents. Therefore, rapid diagnosis of plague on-site in the field is important. Polystyrene microspheres (SMs) of 2.2 μm diameter were synthesized by emulsion polymerization to adsorb magnetic nanoparticles (FNs), resulting in core-/shell-structured microspheres that generate a significant contrast in relative permittivities between SMs and FNs. Electrorheological displays (EDs) consisting of two indium tin oxide glasses with spacers were constructed to contain core-/shell-structured SM/FN (SM@FN) solutions for observing their transmittance change. The ED encapsulating dispersed SM@FN solution exhibited an opaque state because light was scattered significantly without the application of an alternating electric field (AEF). In the presence of an AEF, the particle chaining behavior results in enhancement of the transmittance of ED. At a specific frequency, the so-called characteristic frequency (

Background Yersinia pestis is a contributing agent to the epidemic disease, plague, which killed an estimated 200 million people during historical times. In this study, a rapid, cheap, sensitive, and specific technique, the lateral flow assay (F1 strips), has been successfully developed to detect this pathogen, by using paired monoclonal antibodies (MAbs) against Y. pestis capsule like fraction 1 (F1) protein. Compared with the polyclonal antibody (PAb) based F1 strips, the Mab-based F1 strips have a remarkable increased detection limitation (10 to 100 folds). Furthermore, besides the limitation and specificity evaluation, the application of this F1 strip on simulated clinical samples indicate the LFA can be a good candidate to detect plague. Methods Recombinant F1 antigen was expressed and purified from a series of works. The various anti-F1 monoclonal antibodies generated from hybridoma cells were screened with the ELISA technique. To evaluate the feasibility of this Y. pestis F1 test strip, the F1 protein/Y. pestis was spiked into simulated clinical samples such as human serum, mouse bronchoalveolar lavage fluids, and mouse blood to mimic natural infection status. Additionally, this technique was applied to detect the Y. pestis in the environment-captured rats, to evaluate the practical usefulness of the strips. Results By using this MAb-based-LFA technique, 4 ng/ml of recombinant F1-protein and 103 CFU/ml of Y. pestis could be detected in less than 10 mins, which is at least 10-folds than that of the PAb format. On the other hand, although various Yersinia strains were applied to the strips, only Y. pestis strain showed a positive result; all other Yersinia species did not produce a positive signal, indicating the high efficiency and specificity of the MAb-based F1-strips. Conclusion Based on our findings, we suggest that the MAb-format-LFA will be valuable as a diagnostic tool for the detection of Y. pestis. This report shows that the F1 strip is sufficient to support not only the detection of plague in simulated clinical samples, but also it may be a good candidate to meet the epidemiological surveillance during an outbreak of the biological warfare.

In this work, a unique hybrid system is proposed for one-dimensional gratings comprising of poly(glycidyl methacrylate) (PGMA) brushes and CdS quantum dots (CQDs). Generally, the emission of QDs is too weak to be observed in a dry state. Plasmonic resonances of the grating structures can be used to enhance the light emission or absorption of CQDs. The interaction between PGMA plasmonic nanostructures and inorganic CQDs plays a crucial role in engineering the light harvest, notably for optoelectronic applications. Extinction measurements of the hybrid system consisting of a PGMA grating and CQDs are reported. We designed one-dimensional gratings with various resolutions to tune the absorptance peaks of grating. PGMA grating grafted from a 1.5 &micro, m resolution of trench arrays of photoresist exhibited absorptance peak at 395 nm, close to the absorption peak of CQDs, resulting in the photoluminescence enhancement of CQDs on the grating due to high charge carriers&rsquo, recombination rate. Generally, the emission of quantum dots occurs under irradiation at characteristic wavelengths. Immobilizing QDs on the grating facilitates the emission of QDs under irradiation of full-wavelength light. Furthermore, the PGMA gratings with CQDs were immersed in various solvents to change the geometries resulting the shift of absorptance peak of grating. The proposed method could be applied for sensing the nature of the surrounding media and vice versa, as well as for various media of solvents.

Core/shell structures consisting of polystyrene microspheres (PM, ∼2.2 μm) and Fe3O4 nanoparticles (FeNPs, ∼12.7 nm) were synthesized using a layer-by-layer process to vary the dielectric property. PM@FeNP solutions were encapsulated into home-made sandwich-structured displays (SSDs) to observe their transmittance change under an alternating electric field (AEF). The dispersed PM@FeNP blocked the light traveling through the SSD in the absence of AEF, resulting in an opaque state. In the presence of an AEF, the SSD could display the highest transmittance at the so-called characteristic frequency of the encapsulated microspheres, because of particle chaining. Furthermore, protein G and an antibody were coated onto the PM@FeNP, denoted as PM@FeNP@GIg, for use as a biosensor medium. The characteristic frequency of PM@FeNP@GIg shifted from 300 kHz to 750 kHz after antigen coupling, which could be visualized without any labeling because of the significant change in transmittance. The limit of detection (LOD), ∼40 ng/μL, could be identified within 30 s by the highest transmittance of SSD under AEF at 750 kHz. The transmittance was not affected by BSA or streptavidin, indicating high sensitivity and selectivity. This technique significantly simplifies common immunoassays, which may possess great potential for practical applications in label-free biosensors and visualizing antigen.

Rapid identification of single and multiple infectious agents is vital in clinical settings and during biothreat attack. This study assesses the assay of single-stranded multiplex polymerase chain reaction (PCR) amplicons by suspension bead array (SSMP-SBA) for multiple pathogens identification in a single-tube reaction. A 15-plex assay for identification of 11 highly infectious pathogens was developed to evaluate the performance of SSMP-SBA. Pathogen-specific amplicons were obtained by sequential amplification of genomic DNAs using gene-specific primers tagged with artificial unique sequences and unique primers of which the reverse primer was modified by biotin and phosphorothioate. The SSMP products generated by T7 exonuclease-mediated DNA hydrolysis were hybridized to 15 sets of beads coupled with gene-specific and control oligonucleotide probes for pathogen identification and quantification by flow cytometry. This method was validated via assessment of 57 reference strains and one clinical bacterial isolate. All 11 pathogens can be detected by the 15-plex SSMP-SBA assay, and this design significantly enhanced the signal-to-noise ratio and improved the assay performance. This assay achieves similar sensitivity to our in-house real-time PCR system with the limit of detection equivalent to 5-100 genome copies and a linear dynamic range crossing three to five logs. In the validation assay, a 100% accuracy rate was achieved when the pathogens were among the target species. Notably, the species of pathogens were accurately identified from the samples with multiple infections. SSMP-SBA presents superior performance with multiplexing capability in a single-tube reaction and provides a new approach for detection and species identification of multiple pathogen infections.

The effects of culture and extract solutions of six macrophytes on the growth of three common phytoplankton were investigated under laboratory conditions. Culture solutions were taken from a Hoagland nutrient solution that contained live plants growing for 7 days and the extract solution was made from a solution with fresh plant pieces immersed in Hoagland nutrient solution for 48 h. The algae were grown in the culture or extract solution for 15 days and the algal density was determined every 2 days. The results showed that the culture solution of the macrophytes both inhibited and stimulated algae growth depending on the macrophytes and the algae. All extract solutions of the macrophytes exhibited a stimulatory effect on the growth of the algae that also varied with the macrophytes and the phytoplankton. The results indicated that culture solutions of macrophytes may be more suitable for the control of algal blooms in eutrophic waters than their extract solutions.

Twenty-three ursolic acid (1) derivatives 2-24 (ten novel compounds 8-10, 14-17 and 22-24) modified at the C-3 and the C-28 positions were synthesized, and their structures were confirmed by IR, (1)H NMR, MS, and elemental analysis. The single crystals of compounds 15 and 17 were obtained. The cytotoxic activity of the derivatives was evaluated against HepG2, BGC-823, SH-SY5Y, HeLa and HELF cells by the MTT assay. The induction of apoptosis and affects on the cell cycle distribution with compound 14 were assessed by fluorescence microscopy, flow cytometry and the activity of caspase-3 in HepG2 cells. Compounds 14-17 had more significant antiproliferative ability against the four cancer cell lines and low cytotoxicity to human embryonic lung fibroblast cells (HELF). Compounds 11, 14-16, 21 and 23 were particularly active against HepG2 cell growth. Compound 14 was selected to investigate cell apoptosis and cell cycle distribution. Flow cytometric analysis and morphologic changes of the cell exhibited that treatment of HepG2 cells with compound 14 led to cell apoptosis accompanied by cell cycle arrest at the S phase in a dose-dependent manner. Furthermore, the activity of the caspase-3 enzyme was increased in the treated cells. In vivo studies using H22 xenografts in Kunming mice were conducted with compound 14 at doses of 50, 100 and 150 mg/kg body weight. The results revealed that the medium dosage group (100 mg/kg) showed significant anticancer activity (45.6 ± 4.3%) compared to the control group.

We tested the effects of the floating plant Eichhornia crassipes (water hyacinth) and nonwoven filter for contaminant removal from eutrophic water. Four microcosms were designed for this purpose- (i) water hyacinth plus nonwoven filter; (ii) water hyacinth only; (iii) nonwoven filter only; and, (iv) control with neither water hyacinth nor nonwoven filter. The complex microcosm of water hyacinth and filter had significantly higher percentage removal of total phosphorus (TP) and chemical oxygen demand than found in the treatments without water hyacinth (P < 0.01 or P < 0.05). The complex treatment of water hyacinth and filter maintained a neutral water pH, while pH values in the treatments without E. crassipes reached 10 or even higher within three-five days. The filter treatment eliminated about 60–80% of ammonium nitrogen, nitrate nitrogen, TP, soluble phosphorus, and biochemical oxygen demand in three-six days. The complex treatment of water hyacinth and filter generally had higher removal rates...

Twentythree ursolic acid derivatives including ten novel compounds are synthesized by modification of the C-3 and C-28 positions.

To screen a group of traditional Chinese medicines with effect on pregnane X receptor (PXR)-mediated transcription regulation of P450 3A4 (CYP3A4); and to study whether they can induce the expression of CYP3A4 with a dose, time-dependent manner.Transient cotransfection reporter gene assays were performed with pCI-hPXR-neo, pGL3-CYP3A4-Luc and beta-galactosidase expression plasmid in HepG2 cells.Rhizoma Curcumae, Atractylodes lancea, A. macrocaphala and Poria cocos could induce transcriptional expression of CYP3A4. In the dose-effect study, 24 h after induction, 500 mg x L(-1) Rhizoma Curcumae, A. lancea, A. macrocaphala and Poria cocos, respectively, could induce the CYP3A4 gene expression with (6.82 +/- 0.09), (6.76 +/- 0.20), (5.49 +/- 0.13) and (4.97 +/- 0.07) folds, as compared with 0.1% DMSO treated cells. In the time-effect study, 500 mg x L(-1) Rhizoma curcumae, A. lancea, A. macrocaphala and Poria cocos for 48 h could induce the CYP3A4 gene expression with (7.74 +/- 0.54), (7.34 +/- 0.10), (5.54 +/- 0.11) and (5.32 +/- 0.18) folds, compared with 0.1% DMSO treated cells.Rhizoma Curcumae, A. lancea, A. macrocaphala and Poria cocos could induce the expression of CYP3A4 gene transcription through activating PXR.