Rolling back human pluripotent stem cells to an eight-cell embryo-like stage.

After fertilization, the quiescent zygote experiences a burst of genome activation that initiates a short-lived totipotent state. Understanding the process of totipotency in human cells would have broad applications. However, in contrast to in mice1,2, demonstration of the time of zygotic genome activation or the eight-cell (8C) stage in in vitro cultured human cells has not yet been reported, and the study of embryos is limited by ethical and practical considerations. Here we describe a transgene-free, rapid and controllable method for producing 8C-like cells (8CLCs) from human pluripotent stem cells. Single-cell analysis identified key molecular events and gene networks associated with this conversion. Loss-of-function experiments identified fundamental roles for DPPA3, a master regulator of DNA methylation in oocytes3, and TPRX1, a eutherian totipotent cell homeobox (ETCHbox) family transcription factor that is absent in mice4. DPPA3 induces DNA demethylation throughout the 8CLC conversion process, whereas TPRX1 is a key executor of 8CLC gene networks. We further demonstrate that 8CLCs can produce embryonic and extraembryonic lineages in vitro or in vivo in the form of blastoids5 and complex teratomas. Our approach provides a resource to uncover the molecular process of early human embryogenesis.

[Urinary protein and renal pathological features in children with immunoglobulin A vasculitis with nephritis and hypercoagulability]. / 儿童IgAè¡€ç®¡ç‚Žè‚¾ç‚Žä¼´é«˜å‡çŠ¶æ€çš„å°¿è›‹ç™½å’Œè‚¾è„ç— ç†ç‰¹å¾åˆ†æž.

OBJECTIVES: To study the association of hypercoagulability with urinary protein and renal pathological damage in children with immunoglobulin A vasculitis with nephritis (IgAVN). METHODS: Based on the results of coagulation function, 349 children with IgAVN were divided into a hypercoagulability group consisting of 52 children and a non-hypercoagulability group consisting of 297 children. Urinary protein and renal pathological features were compared between the two groups, and the factors influencing the formation of hypercoagulability in children with IgAVN were analyzed. RESULTS: Compared with the non-hypercoagulability group, the hypercoagulability group had significantly higher levels of urinary erythrocyte count, 24-hour urinary protein, urinary protein/creatinine, urinary immunoglobulin G/creatinine, and urinary N-acetyl-ß-D-glucosaminidase (P<0.05). The hypercoagulability group also had a significantly higher proportion of children with a renal pathological grade of III-IV, diffuse mesangial proliferation, capillary endothelial cell proliferation, or >25% crescent formation (P<0.05). The multivariate logistic regression analysis showed that capillary endothelial cell proliferation and glomerular crescent formation >25% were associated with the formation of hypercoagulability in children with IgAVN (P<0.05). CONCLUSIONS: The renal injury in IgAVN children with hypercoagulability is more severe, with greater than 25% crescent formation and increased proliferation of glomerular endothelial cells being important contributing factors that exacerbate the hypercoagulable state in IgAVN.

Annexin A2: The diversity of pathological effects in tumorigenesis and immune response.

Annexin A2 (ANXA2) is widely used as a marker in a variety of tumors. By regulating multiple signal pathways, ANXA2 promotes the epithelial-mesenchymal transition, which can cause tumorigenesis and accelerate thymus degeneration. The elevated ANXA2 heterotetramer facilitates the production of plasmin, which participates in pathophysiologic processes such as tumor cell invasion and metastasis, bleeding diseases, angiogenesis, inducing the expression of inflammatory factors. In addition, the ANXA2 on the cell membrane mediates immune response via its interaction with surface proteins of pathogens, C1q, toll-like receptor 2, anti-dsDNA antibodies and immunoglobulins. Nuclear ANXA2 plays a role as part of a primer recognition protein complex that enhances DNA synthesis and cells proliferation by acting on the G1-S phase of the cell. ANXA2 reduction leads to the inhibition of invasion and metastasis in multiple tumor cells, bleeding complications in acute promyelocytic leukemia, retinal angiogenesis, autoimmunity response and tumor drug resistance. In this review, we provide an update on the pathological effects of ANXA2 in both tumorigenesis and the immune response. We highlight ANXA2 as a critical protein in numerous malignancies and the immune host response.

Renal Expression of CLC-5 and Megalin/Cubilin in Dent-1 Disease With Nonsense Mutations of CLCN5 Gene.

The study aims to explore the clinicopathological features and whether the nonsense mutations of CLCN5 gene have effect on the renal expression of CLC-5 protein and megalin/cubilin complex in children with Dent-1 disease. The clinicopathological features and genetic examination of three patients with Dent-1 disease were investigated. The expression of CLC-5 and megalin/cubilin complex in renal tissues was detected by using immunohistochemistry method. Urinary albumin, α1-microglobulin, ß2-microglobulin, retinol binding protein, and calcium levels were measured by immunonephelometry. Urinary calcium and low molecular weight proteinuria (LMWP) were enhanced in three patients, and two presented with nephrotic range proteinuria. Focal glomerular obsolescence, minor tubulointerstitial injury, and focal calcification in corticomedullary junction were found in one patient. Nonsense mutations of CLCN5 gene from their mothers were identified in all three patients with Dent-1 disease; however, the expression of CLC-5 protein was not decreased in renal tubular cells. As the receptor complex of albumin and LMWP reabsorption, the expression of megalin/cubilin in the brush border of proximal tubules was decreased in Dent-1 patients. Even if the renal CLC-5 protein is expressed normally, the reduced expression of megalin/cubilin in the brush border of renal proximal tubules may be helpful to understand the physiopathology of Dent-1 disease with nonsense mutations of CLCN5 gene.

Photoswitchable polyynes for multiplexed stimulated Raman scattering microscopy with reversible light control.

Optical imaging with photo-controllable probes has greatly advanced biological research. With superb chemical specificity of vibrational spectroscopy, stimulated Raman scattering (SRS) microscopy is particularly promising for super-multiplexed optical imaging with rich chemical information. Functional SRS imaging in response to light has been recently demonstrated, but multiplexed SRS imaging with reversible photocontrol remains unaccomplished. Here, we create a multiplexing palette of photoswitchable polyynes with 16 Raman frequencies by coupling asymmetric diarylethene with super-multiplexed Carbow (Carbow-switch). Through optimization of both electronic and vibrational spectroscopy, Carbow-switch displays excellent photoswitching properties under visible light control and SRS response with large frequency change and signal enhancement. Reversible and spatial-selective multiplexed SRS imaging of different organelles are demonstrated in living cells. We further achieve photo-selective time-lapse imaging of organelle dynamics during oxidative stress and protein phase separation. The development of Carbow-switch for photoswitchable SRS microscopy will open up new avenues to study complex interactions and dynamics in living cells with high spatiotemporal precision and multiplexing capability.

VGLL1 cooperates with TEAD4 to control human trophectoderm lineage specification.

In contrast to rodents, the mechanisms underlying human trophectoderm and early placenta specification are understudied due to ethical barriers and the scarcity of embryos. Recent reports have shown that human pluripotent stem cells (PSCs) can differentiate into trophectoderm (TE)-like cells (TELCs) and trophoblast stem cells (TSCs), offering a valuable in vitro model to study early placenta specification. Here, we demonstrate that the VGLL1 (vestigial-like family member 1), which is highly expressed during human and non-human primate TE specification in vivo but is negligibly expressed in mouse, is a critical regulator of cell fate determination and self-renewal in human TELCs and TSCs derived from naïve PSCs. Mechanistically, VGLL1 partners with the transcription factor TEAD4 (TEA domain transcription factor 4) to regulate chromatin accessibility at target gene loci through histone acetylation and acts in cooperation with GATA3 and TFAP2C. Our work is relevant to understand primate early embryogenesis and how it differs from other mammalian species.

Fluorescent Ligand-Based Discovery of Small-Molecule Sulfonamide Agonists for GPR120.

As a critical member of G protein-coupled receptors (GPCRs), G protein-coupled receptor 120 (GPR120) is a potential target for many physiological diseases, such as type 2 diabetes mellitus, inflammation, and obesity. Considering that small-molecule fluorescent ligands can combine the advantages of visualization, high sensitivity and selectivity, we initially undertook an effort to develop a series of fluorescent ligands to track GPR120 and establish a method to screen GPR120 agonists. The representative fluorescent ligand N1 possesses suitable optical property, equitable biological activity, and high fluorescence imaging feasibility, therefore, based on compound N1, we subsequently founded a bioluminescence resonance energy transfer (BRET) competition binding assay to screen three series of sulfonamide GPR120 agonists we developed herein. The activity evaluation results revealed that compound D5 was a potent GPR120 agonist with high activity and selectivity. Moreover, compound D5 exhibited a significant glucose-lowering effect in db/db mice, which indicates its potential application in the treatment of type 2 diabetes mellitus in vivo. It is anticipated that our fluorescent ligand-based method is a useful toolbox and will find broad applications in the discovery of small-molecule agonists for GPR120.

Pirfenidone Attenuates Renal Tubulointerstitial Fibrosis through Inhibiting miR-21.

BACKGROUND: Our previous studies had shown pirfenidone (PFD) not only improved tubulointerstitial fibrosis (TIF) but also inhibited the expression of microRNA-21 (miR-21) in the renal tissue of unilateral urethral obstruction (UUO) rats. This study aims to investigate whether PFD can attenuate TIF through inhibiting miR-21 in UUO rats. METHODS: Sprague Dawley rats were divided randomly into sham-operated group, UUO group, and PFD and olmesartan (Olm) treatment groups. Samples were collected on day 14. Expression of miR-21, TGF-ß1, Smad3, and Smad7 mRNA in the renal tissue was detected using real-time quantitative PCR. Immunohistochemistry was performed to assess the protein expressions of collagen III, E-cadherin, and α-SMA. Automated capillary Western blotting was used to detect the quantitative expression of TGF-ß1, Smad3, p-Smad3, Smad7, collagen III, E-cadherin, and α-SMA in renal tissues. The expression of miR-21 and Smad7 mRNA and the protein levels of collagen III and α-SMA were examined in the miR-21-overexpressing cell line, NRK-52E. RESULTS: Compared with the UUO group, both PFD and Olm inhibited renal tubular dilation, diffused epithelial cell degeneration and necrosis, and reduced renal interstitial edema, inflammatory cell infiltration, and collagen fiber deposition, while no significant difference between PFD group and Olm group. Informatics-based approaches identified Smad7 as a likely candidate for regulation by miR-21. Compared with the sham group, miR-21 expression was upregulated in the UUO group resulting in the downregulation of Smad7 expression due to degradation. The overexpression of miR-21 in the in vitro model downregulated Smad7 and promoted EMT and ECM accumulation. Protein levels of TGF-ß1, Smad3, p-Smad3, collagen III, and α-SMA were upregulated, while E-cadherin protein was downregulated in the UUO group than in the sham group. PFD rather than Olm decreased the expression of miR-21 and increased the expression level of Smad7 mRNA and then inhibited the TGF-ß1/Smad3 signaling pathway. Olm only downregulated the TGF-ß1/Smad3 signaling pathway. CONCLUSIONS: PFD improves TIF by downregulating the expression of miR-21, then elevating Smad7, and finally inhibiting the activation of the TGF-ß1/Smad3 signaling pathway in UUO rats.

Generation of an induced pluripotent stem cell line (GIBHi004-A) from a Parkinson's disease patient with mutant DJ-1/PARK7 (p.L10P).

Mutations occurring in the gene body of PARK7 (encoding DJ-1/PARK7) cause autosomal recessive early-onset parkinsonism (AREP). These mutations produce a loss of function and have been reported to lead to dopaminergic neuron degeneration in the substantia nigra. However, the underlying mechanisms are largely unknown. Here, we report the generation of a patient-derived induced pluripotent stem cell (iPSC) line carrying mutant DJ-1 (p.L10P). This cell line is a valuable tool for in vitro Parkinson's disease (PD) modeling and mechanistic studies.

First record of the tropical genus Rambutanura (Collembola: Neanuridae: Neanurinae) in Palearctic, with description of a new species from China.

Genus Rambutanura Deharveng, 1988 of subfamily Neanurinae is herein recorded and a new species is described from China. A key to the species of the whole world of the genus is provided. In order to determine the new species, a new diagnosis within the genus Rambutanura Deharveng, 1988 is proposed. The new species is distinguished from all known members of the genus by its unique set of morphological characters notably: 2+2 depigmented eyes, mandible quadridentate, presence of 1 additional s-chaeta on each tubercle Di from Th. I to Abd. IV, presence of 2 additional s-chaetae on tubercle Dl from Abd. I to Abd. V, presence of guard chaetae sgd and sgv on AOIII, absence of digitate body tubercles.

"On-Water" Facile Synthesis of Novel Pyrazolo[3,4-b]pyridinones Possessing Anti-influenza Virus Activity.

A facile and versatile "on-water" protocol for the synthesis of pyrazolo[3,4-b]pyridinones was developed by the unprecedented construction of two rings and five new bonds in one-pot. It was proved that water was an important promoter of the reaction and PEG2000 was found to improve the reaction in terms of yield. 32 Derivatives were newly synthesized and most of them were prepared in an hour. The scope and limitation indicated that electron withdrawing groups substituted on synthons, substituted benzoyl acetonitriles or aryl aldehydes, were helpful to construct the pyrazolo[3,4-b]pyridinones. The reaction media PEG2000/H2O was successfully recycled and reused at least 5 times without any obvious decrease in yield. The anti-influenza activities of the derivatives were evaluated and the screening results highlighted two derivatives, which exhibited strong inhibitory activity against H5N1 pseudovirus. These positive bioassay results implied that the library of potential anti-influenza virus agent candidates could be rapidly prepared in an eco-friendly manner, and provided a new insight into drug discovery for medicinal chemists.