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1.
Sensors (Basel) ; 21(7)2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33918255

RESUMO

Multiple-camera systems can expand coverage and mitigate occlusion problems. However, temporal synchronization remains a problem for budget cameras and capture devices. We propose an out-of-the-box framework to temporally synchronize multiple cameras using semantic human pose estimation from the videos. Human pose predictions are obtained with an out-of-the-shelf pose estimator for each camera. Our method firstly calibrates each pair of cameras by minimizing an energy function related to epipolar distances. We also propose a simple yet effective multiple-person association algorithm across cameras and a score-regularized energy function for improved performance. Secondly, we integrate the synchronized camera pairs into a graph and derive the optimal temporal displacement configuration for the multiple-camera system. We evaluate our method on four public benchmark datasets and demonstrate robust sub-frame synchronization accuracy on all of them.

2.
Front Med ; 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33909257

RESUMO

Psoraleae Fructus (PF) is a well-known traditional herbal medicine in China, and it is widely used for osteoporosis, vitiligo, and other diseases in clinical settings. However, liver injury caused by PF and its preparations has been frequently reported in recent years. Our previous studies have demonstrated that PF could cause idiosyncratic drug-induced liver injury (IDILI), but the mechanism underlying its hepatotoxicity remains unclear. This paper reports that bavachin isolated from PF enhances the specific stimuli-induced activation of the NLRP3 inflammasome and leads to hepatotoxicity. Bavachin boosts the secretion of IL-1ß and caspase-1 caused by ATP or nigericin but not those induced by poly(I:C), monosodium urate crystal, or intracellular lipopolysaccharide. Bavachin does not affect AIM2 or NLRC4 inflammasome activation. Mechanistically, bavachin specifically increases the production of nigericin-induced mitochondrial reactive oxygen species among the most important upstream events in the activation of the NLRP3 inflammasome. Bavachin increases the levels of aspartate transaminase and alanine aminotransferase in serum and hepatocyte injury accompanied by the secretion of IL-1ß via a mouse model of lipopolysaccharide-mediated susceptibility to IDILI. These results suggest that bavachin specifically enhances the ATP- or nigericin-induced activation of the NLRP3 inflammasome. Bavachin also potentially contributes to PF-induced idiosyncratic hepatotoxicity. Moreover, bavachin and PF should be evaded among patients with diseases linked to the ATP- or nigericin-mediated activation of the NLRP3 inflammasome, which may be a dangerous factor for liver injury.

4.
Cell Chem Biol ; 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33852903

RESUMO

Biofilms are rigid and largely impenetrable three-dimensional matrices constituting virulence determinants of various pathogenic bacteria. Here, we demonstrate that molecular tweezers, unique supramolecular artificial receptors, modulate biofilm formation of Staphylococcus aureus. In particular, the tweezers affect the structural and assembly properties of phenol-soluble modulin α1 (PSMα1), a biofilm-scaffolding functional amyloid peptide secreted by S. aureus. The data reveal that CLR01, a diphosphate tweezer, exhibits significant S. aureus biofilm inhibition and disrupts PSMα1 self-assembly and fibrillation, likely through inclusion of lysine side chains of the peptide. In comparison, different peptide binding occurs in the case of CLR05, a tweezer containing methylenecarboxylate units, which exhibits lower affinity for the lysine residues yet disrupts S. aureus biofilm more strongly than CLR01. Our study points to a possible role for molecular tweezers as potent biofilm inhibitors and antibacterial agents, particularly against untreatable biofilm-forming and PSM-producing bacteria, such as methicillin-resistant S. aureus.

5.
Brief Bioinform ; 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33822873

RESUMO

Single-cell RNA sequencing (scRNA-seq) has enabled us to study biological questions at the single-cell level. Currently, many analysis tools are available to better utilize these relatively noisy data. In this review, we summarize the most widely used methods for critical downstream analysis steps (i.e. clustering, trajectory inference, cell-type annotation and integrating datasets). The advantages and limitations are comprehensively discussed, and we provide suggestions for choosing proper methods in different situations. We hope this paper will be useful for scRNA-seq data analysts and bioinformatics tool developers.

6.
Environ Sci Technol ; 55(8): 4430-4439, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33721996

RESUMO

Large amounts of small α-dicarbonyls (glyoxal and methylglyoxal) are produced in the atmosphere from photochemical oxidation of biogenic isoprene and anthropogenic aromatics, but the fundamental mechanisms leading to secondary organic aerosol (SOA) and brown carbon (BrC) formation remain elusive. Methylglyoxal is commonly believed to be less reactive than glyoxal because of unreactive methyl substitution, and available laboratory measurements showed negligible aerosol growth from methylglyoxal. Herein, we present experimental results to demonstrate striking oligomerization of small α-dicarbonyls leading to SOA and BrC formation on sub-micrometer aerosols. Significantly more efficient growth and browning of aerosols occur upon exposure to methylglyoxal than glyoxal under atmospherically relevant concentrations and in the absence/presence of gas-phase ammonia and formaldehyde, and nonvolatile oligomers and light-absorbing nitrogen-heterocycles are identified as the dominant particle-phase products. The distinct aerosol growth and light absorption are attributed to carbenium ion-mediated nucleophilic addition, interfacial electric field-induced attraction, and synergetic oligomerization involving organic/inorganic species, leading to surface- or volume-limited reactions that are dependent on the reactivity and gaseous concentrations. Our findings resolve an outstanding discrepancy concerning the multiphase chemistry of small α-dicarbonyls and unravel a new avenue for SOA and BrC formation from atmospherically abundant, ubiquitous carbonyls and ammonia/ammonium sulfate.


Assuntos
Carbono , Glioxal , Aerossóis , Sulfato de Amônio , Aldeído Pirúvico
7.
Artigo em Inglês | MEDLINE | ID: mdl-33765765

RESUMO

When superhydrophobic meshes are used for oil/water separation, high flux and high intrusion pressure are usually compromised. Herein, a high-performance superhydrophobic stainless steel mesh membrane with a hairy-like poly(divinylbenzene) (PDVB) coating is fabricated by precipitated cationic polymerization. The synthesis is facile, which is completed in one step at ambient temperature within a short time, i.e., less than 90 s. The unique hair-like microstructure of PDVB is responsible for the superhydrophobic performance with less blockage for the pores. A higher flux for oil is achieved while keeping a high intrusion pressure. Especially, the ellipsoidal pore texture with two sharp tips can give additional high intrusion pressure. In the case of 2800 mesh, the superhydrophobic mesh displays an unprecedentedly high value of up to 22 kPa while maintaining a high flux of 2.0 × 104 L·m-2·h-1. The high intrusion pressure enables further increment of flux to 4.2 × 104 L·m-2·h-1 under a reduced pressure at a higher loading. The current high-performance superhydrophobic mesh realizes higher efficiency in separating oil/water mixtures, which is promising for practical applications, for example, in industrial extraction.

8.
Mol Cell Endocrinol ; 527: 111228, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33662476

RESUMO

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders in reproductive-age women. In this study, BPTF associated protein of 18 kDa (BAP18) is decreased in luteinized granulosa cells (GCs) from PCOS women. BAP18 depletion significantly decreases CYP19A1 expression levels, leading to an abrogation in transfer capacity of androgen to estrogen in GCs. Also, BAP18 knockdown delays cell cycle G1 to S phase transition and induces cell apoptosis to decrease GCs proliferation. We also provide evidence showing BAP18 interacts with androgen receptor (AR) and enhances AR-mediated transactivation in GCs. Results indicate that AR or BAP18 recruits to androgen response elements (AREs) of CYP19A1 and FSHR, which are putative AR-induced genes in GCs. BAP18 interacts with Sp1 transcription factor and co-recruits to the promoter region of AR gene, resulting in AR transactivation in GCs. Taken together, these data provide new insights on the pathophysiology of PCOS.

10.
Neurol India ; 69(1): 115-118, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33642281

RESUMO

Context: A host of microRNAs have been reported to suppress tumor growth, invasion, and metastasis and play roles in neurodegeneration disorders. Moreover, microRNA changes are found in the peripheral blood, cerebrospinal fluid (CSF), and brain tissues of central nervous system diseases, including glioma, Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis, and depression. Compared with other body fluids, CSF can reflect the brain pathological processes more accurately. Aims: To understand whether microRNA expression may be misregulated in patients with PD, and further discover potential diagnostic biomarkers and promising therapeutic targets for PD. Materials and Methods: Here, through real-time reverse-transcription polymerase chain reaction (RT-PCR), we compared CSF microRNA from 15 PD patients, 11 AD patients, and 16 controls with other neurologic disorders, such as encephalitis and Guillain-Barre syndrome. Results: Finally, we identified hsa-miR-626 changes in the CSF of PD patients. The mean expression level of hsa-miR-626 was significantly reduced in the CSF of PD patients compared with AD patients and controls. Conclusions: Our approach provides a preliminary research for identifying biomarkers in the CSF that could be used for the detection, diagnosis, and monitoring of PD.

12.
Commun Biol ; 4(1): 198, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33580179

RESUMO

Cystatin C (Cst-3) is a potent inhibitor of cysteine proteases with diverse biological functions. As a secreted protein, the potential interaction between Cst-3 and extracellular matrix components has not been well studied. Here we investigated the interaction between Cst-3 and heparan sulfate (HS), a major component of extracellular matrix. We discovered that Cst-3 is a HS-binding protein only at acidic pH. By NMR and site-directed mutagenesis, we identified two HS binding regions in Cst-3: the highly dynamic N-terminal segment and a flexible region located between residue 70-94. The composition of the HS-binding site by two highly dynamic halves is unique in known HS-binding proteins. We further discovered that HS-binding severely impairs the inhibitory activity of Cst-3 towards papain, suggesting the interaction could actively regulate Cst-3 activity. Using murine bone tissues, we showed that Cst-3 interacts with bone matrix HS at low pH, again highlighting the physiological relevance of our discovery.

13.
Cancer Sci ; 112(5): 1865-1877, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33544437

RESUMO

The histone acetyltransferase MOF (KAT8) is mainly involved in the acetylation of histone H4 at lysine 16 (H4K16) and some non-histone proteins. The MOF expression level is significantly reduced in many cancers, however the biological function of MOF and its underlying mechanism are still elusive in hepatocellular carcinoma (HCC). Estrogen receptor α (ERα) has been considered as a tumor suppressor in HCC. Here, we demonstrated that MOF expression is significantly reduced in HCC samples, and is positively correlated with that of ERα. MOF interacts with ERα, and participates in acetylation of ERα at K266, K268, K299, thereby inhibiting ERα ubiquitination to maintain the stability of ERα. In addition, MOF participates in the upregulation of ERα-mediated transactivation. Depletion of MOF significantly promotes cell growth, migration, and invasion in HCC cell lines. Taken together, our results provide new insights to understand the mechanism underlying the modulation function of MOF on ERα action in HCC, suggesting that MOF might be a potential therapeutic target for HCC.

14.
Artigo em Inglês | MEDLINE | ID: mdl-33556022

RESUMO

Many data sources, such as human poses, lie on low-dimensional manifolds that are smooth and bounded. Learning low-dimensional representations for such data is an important problem. One typical solution is to utilize encoder-decoder networks. However, due to the lack of effective regularization in latent space, the learned representations usually do not preserve the essential data relations. For example, adjacent video frames in a sequence may be encoded into very different zones across the latent space with holes in between. This is problematic for many tasks such as denoising because slightly perturbed data have the risk of being encoded into very different latent variables, leaving output unpredictable. To resolve this problem, we first propose a neighborhood geometric structure-preserving variational autoencoder (SP-VAE), which not only maximizes the evidence lower bound but also encourages latent variables to preserve their structures as in ambient space. Then, we learn a set of small surfaces to approximately bound the learned manifold to deal with holes in latent space. We extensively validate the properties of our approach by reconstruction, denoising, and random image generation experiments on a number of data sources, including synthetic Swiss roll, human pose sequences, and facial expression images. The experimental results show that our approach learns more smooth manifolds than the baselines. We also apply our approach to the tasks of human pose refinement and facial expression image interpolation where it gets better results than the baselines.

15.
Nat Commun ; 12(1): 986, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33579943

RESUMO

Epigallocatechin gallate (EGCG) from green tea can induce apoptosis in cancerous cells, but the underlying molecular mechanisms remain poorly understood. Using SPR and NMR, here we report a direct, µM interaction between EGCG and the tumor suppressor p53 (KD = 1.6 ± 1.4 µM), with the disordered N-terminal domain (NTD) identified as the major binding site (KD = 4 ± 2 µM). Large scale atomistic simulations (>100 µs), SAXS and AUC demonstrate that EGCG-NTD interaction is dynamic and EGCG causes the emergence of a subpopulation of compact bound conformations. The EGCG-p53 interaction disrupts p53 interaction with its regulatory E3 ligase MDM2 and inhibits ubiquitination of p53 by MDM2 in an in vitro ubiquitination assay, likely stabilizing p53 for anti-tumor activity. Our work provides insights into the mechanisms for EGCG's anticancer activity and identifies p53 NTD as a target for cancer drug discovery through dynamic interactions with small molecules.


Assuntos
Apoptose/efeitos dos fármacos , Catequina/análogos & derivados , Catequina/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/química , Proteína Supressora de Tumor p53/química , Sítios de Ligação , Linhagem Celular Tumoral , Epitopos , Humanos , Ligação Proteica , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Espalhamento a Baixo Ângulo , Chá , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Difração de Raios X
16.
Int J Biol Sci ; 17(1): 188-203, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33390843

RESUMO

Androgen receptor (AR) and its variants play vital roles in development and progression of prostate cancer. To clarify the mechanisms involved in the enhancement of their actions would be crucial for understanding the process in prostate cancer and castration-resistant prostate cancer transformation. Here, we provided the evidence to show that pre-mRNA processing factor 6 (PRPF6) acts as a key regulator for action of both AR full length (AR-FL) and AR variant 7 (AR-V7), thereby participating in the enhancement of AR-FL and AR-V7-induced transactivation in prostate cancer. In addition, PRPF6 is recruited to cis-regulatory elements in AR target genes and associates with JMJD1A to enhance AR-induced transactivation. PRPF6 also promotes expression of AR-FL and AR-V7. Moreover, PRPF6 depletion reduces tumor growth in prostate cancer-derived cell lines and results in significant suppression of xenograft tumors even under castration condition in mouse model. Furthermore, PRPF6 is obviously highly expressed in human prostate cancer samples. Collectively, our results suggest PRPF6 is involved in enhancement of oncogenic AR signaling, which support a previously unknown role of PRPF6 during progression of prostate cancer and castration-resistant prostate cancers.

17.
Artigo em Inglês | MEDLINE | ID: mdl-33430588

RESUMO

Enhanced emission and adjustable wavelength for single luminogen systems are highly desirable in the scope of photoluminescent materials. Herein, a supramolecular strategy has been proposed for supramolecular assembly-induced enhanced emission and valid emission manipulation by fabricating an amphiphilic copolymer host material with pillar[5]arene units as the side chains, whereby cyanovinylene-based (CV) derivatives are anchored to the polymer hosts via host-guest interactions. The guest-bearing copolymers can further form luminescent supramolecular polymer nanoparticles (SPNs). Remarkably, the as-prepared SPNs exhibit dramatic emission enhancement and tunable fluorescence wavelength, ascribing to the synergetic effects involving the restriction of intramolecular motions and the prevented excimer formation for CV moieties, as endowed by host-guest interactions and the entanglement of the polymer chains. Furthermore, the SPNs can be established as efficient artificial light-harvesting systems via the inclusion of Nile red into the particles for broadened emission spectra. As a proof-of-concept study, the use of pillar[5]arene-containing polymer hosts largely facilitates the emission enhancement and wavelength adjustment for the inherent luminogens, setting the basis for the supramolecular design of highly tunable luminescent systems.

18.
Bioorg Chem ; 107: 104583, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33421956

RESUMO

BACKGROUND: Indoles are important bioactive compounds that have been extensively studied in organic chemistry. In this work, a green and efficient process for the synthesis of Indoles from 1,3-diketones with fumaronitrile was developed. RESULTS: Under optimal conditions (1,3-diketones (0.5 mmol), fumaronitrile (1 mmol), water (2 ml), lipase (15 mg), 30 °C, 24 h), high yields and satisfactory regioselectivity of cyano-containing multi-substituted indoles could be obtained when CRL (C. rugosa lipase) was used as the catalyst. CONCLUSION: This enzymatic method demonstrates the great potential for the synthesis of indoles and extends the application of enzyme in organic synthesis.

19.
Int J Med Sci ; 18(3): 763-767, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33437211

RESUMO

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and is an emerging disease. There has been a rapid increase in cases and deaths since it was identified in Wuhan, China, in early December 2019, with over 4,000,000 cases of COVID-19 including at least 250,000 deaths worldwide as of May 2020. However, limited data about the clinical characteristics of pregnant women with COVID-19 have been reported. Given the maternal physiologic and immune function changes during pregnancy, pregnant women may be at a higher risk of being infected with SARS-CoV-2 and developing more complicated clinical events. Information on severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) may provide insights into the effects of COVID-19's during pregnancy. Even though SARS and MERS have been associated with miscarriage, intrauterine death, fetal growth restriction and high case fatality rates, the clinical course of COVID-19 pneumonia in pregnant women has been reported to be similar to that in non-pregnant women. In addition, pregnant women do not appear to be at a higher risk of catching COVID-19 or suffering from more severe disease than other adults of similar age. Moreover, there is currently no evidence that the virus can be transmitted to the fetus during pregnancy or during childbirth. Babies and young children are also known to only experience mild forms of COVID-19. The aims of this systematic review were to summarize the possible symptoms, treatments, and pregnancy outcomes of women infected with COVID-19 during pregnancy.


Assuntos
/epidemiologia , Transmissão Vertical de Doença Infecciosa , Complicações Infecciosas na Gravidez/epidemiologia , Resultado da Gravidez , /imunologia , Adulto , /terapia , Feminino , Humanos , Recém-Nascido , Exposição Materna , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/terapia , Complicações Infecciosas na Gravidez/virologia , Vírus da SARS/imunologia , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/imunologia , Síndrome Respiratória Aguda Grave/virologia , Índice de Gravidade de Doença
20.
J Ovarian Res ; 14(1): 17, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33478578

RESUMO

This study investigated the effect of recombinant human lactoferrin (rhLF) on the premature ovarian failure (POF) of rats. After cyclophosphamide treatments, the POF rats were divided into the following groups: normal control group (NC), low-dose group (LD), medium-dose group (MD) and high-dose group (HD) of rhLF. After drug administrations, the ovarian indexes and hormonal levels were detected. After follicle number count, the proliferation and apoptosis were analyzed with the expressions of genes related with oogenesis, reactive oxygen species (ROS) production and apoptosis detected, followed by the calculation of oxidative stress and protein expressions. After 4-hydroperoxy cyclophosphamide (4-HC) treatments, the effect of rhLF on the proliferation, ROS production and gene expressions of primary rat granulosa cells (GCs) cultured in vitro were detected. After mating, the fertilities of POF rats were recorded. The result showed that the rhLF administrations up-regulated the ovarian index with the number of developing follicles increased and the decreases of hormonal levels conferred. The Ki-67 intensities of the MD and HD groups were up-regulated with the Tunnel intensities decreased. The rhLF treatments significantly promoted the expression of oogenesis, antioxidant and anti-apoptosis related genes. The expression of Bax and Caspase 3 were decreased with the expression of Bcl-2 up-regulated after rhLF administrations. The in vitro treatments of rhLF effectively conferred the toxicity of 4-HC on primary rat GCs. The fertility assessment showed the rhLF treatments up-regulated the offspring's' folliculogenesis, which confirmed the ameliorative role of rhLF on the POF damages via the inhibition of ROS production in GCs.

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