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Fluorogenic labeling is a potential technique in biology that allows for direct detection and tracking of cells undergoing various biological processes. Compared to traditional genetic modification approaches, labeling cells with nanoparticles has advantages, especially for the additional safety they provide by avoiding genomic integration. However, it remains a challenge to determine whether nanoparticles interfere with cell traits and provide long-lasting signals in living cells. We employed an amphiphilic fluorophore-derived nanoparticle (denoted by TPE-11) bearing a tetraphenylethene (TPE) moiety and two ionic heads; this nanoparticle has an aggregation-induced emission (AIE) effect and the ability to self-assemble. TPE-11 exhibited the property of higher or longer fluorescence intensities in cell imaging than the other two nanomaterials under the same conditions. We used this nanomaterial to label human embryonic stem (hES) cells and monitor their differentiation. Treatment with low concentrations of TPE-11 (8.0 μg/mL) resulted in high-intensity labeling of hES cells, and immunostaining analysis and teratoma formation assays showed that at this concentration, their pluripotency remained unaltered. TPE-11 nanoparticles allowed for long-term monitoring of hES cell differentiation into neuron-like cells; remarkably, strong nanoparticle signals were detected throughout the nearly 40-day differentiation process. Thus, these results demonstrate that the TPE-11 nanoparticle has excellent biocompatibility for hES cells and is a potential fluorogen for labeling and tracking the differentiation of human pluripotent stem cells. Statement of Significance This study uses a nanoparticle-based approach to label human embryonic stem (hES) cells and monitor their differentiation. hES cells are distinguished by two distinctive properties: the state of their pluripotency and the potential to differentiate into various cell types. Thus, these cells will be useful as a source of cells for transplantation or tissue engineering applications. We noticed the effect of aggregation-induced emission, and the ability to self-assemble could enhance the persistence of signals. Treatment with low concentrations of TPE-11 nanoparticles showed high-intensity labeling of hES cells, and immunostaining analysis and teratoma formation assays showed that at this concentration, their pluripotency remained unaltered. Additionally, these nanoparticles allowed for long-term monitoring of hES cell differentiation into neuron-like cells lasting for 40 days.

This paper proposes a real-time, continuous pedestrian tracking and positioning method with multiple coordinated overhead-view cameras. First, a discriminative correlation filter with detection and space reliability (DSR-DCF) is presented for continuous, real-time pedestrian tracking with single cameras. Then, the frame difference method is employed to detect moving pedestrians when they walk from one camera’s view to another’s. Motion-area images are cropped to establish a pedestrian image library (PIL). Finally, this PIL is relied upon to reidentify pedestrians. Pedestrian positioning is realized based on the pinhole imaging model. Tracking and positioning experiments showed the following. DSR-DCF is stable with a high success rate. Its tracking speed exceeds 24 fps. It produces a success rate higher than 90% for cross-camera pedestrian tracking and misses no pedestrians. It yields stable pedestrian positioning results with an accuracy better than 0.2 m. The proposed algorithm will be used in airport terminals.

Trophoblast cells are important in embryo implantation and fetomaternal tolerance. HLA-G is specifically expressed at the maternal–fetal interface and is a regulator in pregnancy. The aim of the present study was to detect the effect of HLA-G1 on trophoblast cell proliferation, adhesion, and invasion. Human trophoblast cell lines (JAR and HTR-8/SVneo cells) were infected with HLA-G1-expressing lentivirus. After infection, HLA-G1 expression of the cells was detected by western blotting. Cell proliferation was detected by the BrdU assay. The cell cycle and apoptosis of JAR and HTR-8/SVneo cells was measured by flow cytometry (FCM). The invasion of the cells under different conditions was detected by the transwell invasion chamber assay. HLA-G1 didn't show any significant influence on the proliferation, apoptosis, adhesion, and invasion of trophocytes in normal culture conditions. However, HLA-G1 inhibited JAR and HTR-8/SVneo cells invasion induced by hepatocyte growth factor (HGF) under normal oxygen conditions. In conditions of hypoxia, HLA-G1 couldn't inhibit the induction of cell invasion by HGF. HLA-G1 is not an independent factor for regulating the trophocytes. It may play an indirect role in embryo implantation and formation of the placenta.

Human leukocyte antigen (HLA)-G is thought to confer fetal–maternal tolerance and play a crucial role in ensuring a successful pregnancy. There is increasing evidence that HLA-G is regulated at the post-transcriptional level. This study investigated the role of miR-133a in regulating HLA-G expression and the pathogenesis of recurrent spontaneous abortion (RSA). Twelve patients (25–30years) with RSA at 7 gestational weeks were screened by array-based comparative genome hybridization: 16.7% were found to have an abnormal karyotype and all induced abortion (IA) patients had normal karyotype. The villi of RSA and IA patients with normal karyotype were further screened by miRNA microarrays. Multi-software prediction and real-time PCR confirmed that miR-133a was most likely to bind to HLA-G 3′ untranscribed region (UTR). Relevance analysis showed that, compared with IA villi, miR-133a was greatly overexpressed in RSA villi with normal karyotype ( P Human leukocyte antigen (HLA)-G is supposed to confer fetal–maternal tolerance and plays a crucial role in successful pregnancy. Accumulating evidence indicates that HLA-G is mainly regulated at the post-transcriptional level. Our study aimed to further investigate the key role of a microRNA, miR-133a, in regulating HLA-G expression and the pathogenesis of recurrent spontaneous abortion (RSA). Our findings indicated that miR-133a regulates HLA-G expression by inhibiting its translation, and suggest that it is involved in the pathogenesis of RSA.

The equilibrium structures and relative stabilities of BN substituted fullerenes C60−2x(BN)x (x=1–3) have been studied using AM1 and MNDO semi-empirical methods. The calculation results obtained by both methods indicated that the BN substituted fullerenes are less stable than C60. The homo–lumo splitting and heat of formation suggests that the isomer of C58BN in which two neighboring carbon atoms between the six- and six- membered ring are substituted by BN units is the most stable species. The stabilities of C58BN decrease with increasing the distance between the heteroatoms. For C56(BN)2, the calculation results show that N–N and B–B bonds should be avoided and the smallest number of the C–X bonds is preferred for the stable isomer of C56(BN)2 and the isomer in which the B–N–B–N bond is formed has the lowest heat of formation, thus the most stable species. The structure of the most stable isomer of C54(BN)3 has been proposed based on the calculations on various isomers of C58BN and C56(BN)2, i.e. the most energetic favorable C54(BN)3 should have three BN units located in the same hexagon to form B–N–B–N–B–N ring. The BN substituted fullerenes C60−2x(BN)x have somewhat smaller ionization potentials and bigger affinity potentials compared with C60, which suggests that it is easier to oxidize and reduce C60−2x(BN)x relative to C60, thus the redox characteristics of C60 can be enhanced by doping. Based on the optimized geometries, the electronic spectra for these BN doped fullerenes have been calculated using INDO/CIS method

The equilibrium structures, relative stabilities of substituted fullerenes C 58 B 2 , C 58 N 2 and C 58 BN have been studied at the AM1, PM3, MNDO and INDO level. The calculation results obtained by all these semi-emperical methods show that the substituted fullerenes are less stable than C 60 , 6–6 isomers are the most stable species for C 58 B 2 , C 58 N 2 and C 58 BN, the stabilities decrease with the increase of the distance between the heteroatoms. The calculation results also show that the stability of C 58 BN is considerably higher than that of C 58 N 2 , and the stability of C 58 N 2 is considerably higher than that of C 58 B 2 . Calculations on the C 58 B 2 -(NH 3 ) 2 adducts have been employed in this paper to evaluate Smally's proposition on the substitute preference of C 58 B 2 . The elctronic spectra for these doped fullerenes have been calculated using INDO/CIS method