Search

Approximately 15–25% pregnant women end with miscarriage in the world. Environmental BaP (benzo(a)pyrene) and its terminal metabolite BPDE (benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide) may result in the dysfunctions of trophoblast cells, which might further lead to RM (recurrent miscarriage). However, potential mechanisms remain unelucidated. In this work, we identified a novel lnc-HZ05 highly expressed and a novel miR-hz05 lowly expressed in both trophoblast cells exposed to BPDE and human RM tissues. MiR-hz05 reduces FOXO3a mRNA level by weakening its mRNA stability. Lnc-HZ05 increases the expression of FOXO3a by acting as a ceRNA for miR-hz05, and then increases P21 level and reduces CDK2 level. Thus, cell cycle is arrested at G0/G1 phase and trophoblast proliferation is inhibited. Lnc-HZ05 harboring wild-type binding site for miR-hz05, but not its mutant site, could upregulate FOXO3a expression. In normal trophoblast cells, relatively less lnc-HZ05 and more miR-hz05 activate FOXO3a/P21/CDK2 pathway and promote trophoblast proliferation, giving normal pregnancy. In RM tissues and BPDE-treated human trophoblast cells, lnc-HZ05 is increased and miR-hz05 is reduced, both of which suppress this pathway and inhibit cell proliferation, and finally lead to miscarriage. Thus, lnc-HZ05 and miR-hz05 simultaneously regulate cell cycle and proliferation of BPDE-exposed trophoblast cells and miscarriage, providing new perspectives and clinical understandings in the occurrence of unexplained miscarriage. [ABSTRACT FROM AUTHOR]

d-proline and N-boc-5-hydroxy-l-proline are key chiral intermediates in the production of eletriptan and saxagliptin, respectively. An efficient proline racemase–proline dehydrogenase cascade was developed for the enantioselective production of d-proline. It included the racemization of l-proline to dl-proline and the enantioselective dehydrogenation of l-proline in DL-proline. The racemization of l-proline to dl-proline used an engineered proline racemase (ProR). l-proline up to 1000 g/L could be racemized to dl-proline with 1 g/L of wet Escherichia coli cells expressing ProR within 48 h. The efficient dehydrogenation of l-proline in dl-proline was achieved using whole cells of proline dehydrogenase-producing Pseudomonas pseudoalcaligenes XW-40. Moreover, using a cell-recycling strategy, d-proline was obtained in 45.7% yield with an enantiomeric excess of 99.6%. N-boc-5-hydroxy-l-proline was also synthesized from l-glutamate semialdehyde, a dehydrogenated product of l-proline, in a 16.7% yield. The developed proline racemase–proline dehydrogenase cascade exhibits great potential and economic competitiveness for manufacturing d-proline and N-boc-5-hydroxy-l-proline from l-proline. [ABSTRACT FROM AUTHOR]

Increasing evidences have shown that pregnant women might miscarry after exposure with environmental BaP (benzo(a)pyrene). Additionally, BPDE (benzo(a)pyren-7,8-dihydrodiol-9,10-epoxide), the ultimate metabolite of BaP, could induce dysfunctions of human trophoblast cells. However, it is rarely correlated between miscarriage and trophoblast dysfunctions. Moreover, their underlying mechanisms are still largely unidentified. In this study, a novel lncRNA (long non-coding RNA), lnc-HZ08, was identified to be highly expressed in human recurrent miscarriage (RM) tissues and in BPDE-treated human trophoblast cells. Lnc-HZ08 acts as a RNA scaffold to interact with both PI3K and its ubiquitin ligase CBL (Cbl proto-oncogene), enhances their protein interactions, and promotes PI3K ubiquitin degradation. In RM tissues and BPDE-treated trophoblast cells, DNA methylation level in lnc-HZ08 promoter region was reduced, which promotes estrogen receptor 1 (ER)–mediated lnc-HZ08 transcription. Subsequently, this upregulated lnc-HZ08 downregulated PI3K level, suppressed PI3K/p-AKT/p-P21/CDK2 pathway, and thus weakened proliferation, migration, and invasion of human trophoblast cells, which further induces miscarriage. These results may provide novel scientific and clinical insights in the occurrence of unexplained miscarriage. [ABSTRACT FROM AUTHOR]

Normal pregnancy is essential for human reproduction. However, environmental BaP (benzo(a)pyrene) and its metabolite BPDE (benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide) induce dysfunctions of human trophoblastic cells, which could further result in miscarriage. Yet, the molecular mechanisms remain poorly understood. In this work, a novel lnc-HZ03 and a novel miR-hz03 were identified. Both lnc-HZ03 and miR-hz03 were highly expressed in human recurrent miscarriage villous tissues and in BPDE-exposed trophoblastic cells. Lnc-HZ03 and miR-hz03 upregulated each other, forming a positive feedback loop. MiR-hz03 could also upregulate p53 level by enhancing its mRNA stability. Both lnc-HZ03 and p53 mRNA contained the target site for miR-hz03 and could directly interact with miR-hz03. It was this target site instead of its mutant on lnc-HZ03 that regulated p53 expression. Subsequently, the upregulated p53 facilitated SAT1 transcription and enhanced SAT1-catalyzed spermine metabolism, which further resulted in trophoblastic cell apoptosis and induced miscarriage. All together, the p53/SAT1 pathway upregulated by lnc-HZ03 and miR-hz03 could promote BPDE-induced human trophoblastic cell apoptosis and the occurrence of miscarriage, shedding novel light on the causes of miscarriage. [ABSTRACT FROM AUTHOR]

Person re-identification (reID) aims at finding the same person in different camera views. In real-world scenarios, it is quite often that the suspect's appearance is not known while the suspect's escape route is known. This paper introduces a new person reID setting, where the query includes both the real suspect's trajectory and several possible suspects. The goal is to identify the actual suspect and retrieve images of the real suspect. Prior work focuses on extracting pedestrians' discriminative visual features or using spatial-temporal information while neglecting the importance of cross-camera trajectory information. Due to the spatial-temporal consistency, the trajectory and image complement each other and the trajectory is associated with the image data. Therefore, we consider retrieving the suspect's image based on the trajectory and introducing a Hidden Markov Model based trajectory framework to jointly analyze image data and trajectory information. We evaluate our methods on two datasets containing person images and trajectory information, demonstrating our approach's effectiveness. [ABSTRACT FROM AUTHOR]