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Narrow QRS complex tachycardia has a broad differential diagnosis. We present a series of rhythm strips with representative onset, transition from 2:1 AV conduction to 1:1 AV conduction, and offset of tachycardia. By analyzing these rhythm strips, we can identify the electrophysiologic mechanism and diagnosis. (

Triptolide (TP) has an anti-proteinuric effect and is used for the treatment of podocytopathies. TP has also been shown to act directly on immortalized podocytes in culture to protect them from injury. In the present study, we examined the effect of TP on healthy podocytes both in vitro and in vivo to better understand the action of TP on podocytes. We found that treatment of TP at 10 ng/ml, a concentration that is routinely used for podocyte protection, was sufficient to activate pro-apoptotic signaling of MAPK p38, p53 and BAX and induced apoptosis in cultured podocytes; and higher concentrations of TP exacerbated the p38, p53 and BAX activations and apoptosis. Moreover, TP severely downregulated the genes that are essential for podocyte structure and function. Interestingly, in contrast with other agents TP-induced podocyte injury was not prevented by glucocorticoids. In vivo, high-dose TP treatment for prolonged time did not cause podocyte injury, essential genes downregulation, and proteinuria in mice. TP was also not toxic to the podocytes with isolated glomeruli ex vivo. In summary, TP is toxic to immortalized podocytes in culture but not to the podocytes in animals or isolated glomeruli ex vivo. Our study suggests that immortalized podocytes might have genetically evolved to become sensitive to TP toxicity and thus caution should be taken in interpreting data from immortalized podocytes. Nevertheless, in vivo TP could be as safe as glucocorticoids in treating podocytopathies. Finally, TP may be used as a unique in vitro model for studying steroid-resistant podocytopathies.

Gene expression differs substantially among individual cells of the same type. We speculate that genes that are expressed in all but a portion of cells of a given cell type would be likely essential and required for either the cell survival (housekeeping) or for the cell type's unique structure and function, enabling the organism to survive. Here, we performed RNA-seq of 20 mouse podocytes using the Fluidigm C1 system and identified 335 genes that were expressed in all of them. Among them, 239 genes were also expressed in mesangial and endothelial cells and were involved in energy metabolism, protein synthesis, etc., as housekeeping genes. In contrast, 92 genes were preferentially expressed in podocytes (over five-fold versus expression in mesangial and endothelial cells) and are, therefore, the essential candidate genes specific for podocytes. Assessments by bioinformatics, conserved expression in human podocytes, and association with injury/disease all support the essentiality of these genes for podocytes. Factually, 27 of the 92 genes are already known to be essential for podocyte structure and function. Thirty-seven novel genes were functionally analyzed by siRNA silencing, and we found that a deficiency of 30 genes led to either cytoskeletal injury (FGFR1, AOX1, AIF1L, HAUS8, RAB3B, LPIN2, GOLIM4, CERS6, ARHGEF18, ARPC1A, SRGAP1, ITGB5, ILDR2, MPP5, TSC22D1, DNAJC11, SEPT10, MOCS2, FNBP1L, and TMOD3) or significant downregulation of CD2AP and synaptopodin (IFT80, MYOM2, ANXA4, CYB5R4, GPC1, ZNF277, NSF, ITGAV, CRYAB, and MTSS1). Thus, the list of genes essential for podocyte cytoskeletons is expanded by single-cell RNA sequencing. It appears that podocyte-specific essential genes are mainly associated with podocyte cytoskeletons.

Pu-erh tea has become one of the popular and widely consumed teas because of its health benefits resulted from various bioactive compounds that are microbially produced during Pu-erh tea production. We applied 16S rRNA gene amplicon sequencing and analytical tools to investigate microbiomes and associated chemical profiles of five raw and five ripened Pu-erh teas from different manufacturers. Contrasting bacterial and fungal microbiomes of raw and ripened Pu-erh tea samples associated with distinct chemical profiles were revealed. The ripened Pu-erh teas had a higher bacterial diversity but lower fungal diversity than the raw Pu-erh teas. Firmicutes and Proteobacteria were the dominant phyla in the ripened and raw Pu-erh tea, respectively. Cyanobacteria phylum was found very abundant in the raw but rarely present in the ripened Pu-erh tea. Ascomycota was the dominant fungal phylum in both ripened and raw Pu-erh tea. Tea polysaccharide and gallocatechin gallate were the characteristic chemicals in the ripened Pu-erh tea; while caffeic acid, caffeine, EGC, ECG, EGCG, C, and GA were more representative in the raw Pu-erh tea. These results will assist in further cultivating and characterizing the representative microorganisms in Pu-erh teas of different origins, and improve our understanding of microbial-mediated Pu-erh tea production process.

Zinc phthalocyanine (ZnPc) modified by cyanuric chloride was supported on TiO2–SiO2 microparticles (ZnPc–SiO2–TiO2) by covalent bonds to produce a novel photosensitizer, ZnPc–SiO2–TiO2. ZnPc sensitized TiO2 to light in the visible range, while the TiO2 acted as an acceptor of electrons generated by the photon irradiation; thus, this material can absorb low-energy photons to emit photons of higher energy. The as-prepared ZnPc–SiO2–TiO2 was characterized using X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and UV–vis diffuse reflectance spectroscopy (DRS). The results of photodecomposing methylene blue (MB) revealed that ZnPc–SiO2–TiO2 had great photocatalytic activity under visible-light irradiation (λ>400 nm). By analyzing electron paramagnetic resonance (EPR) spectra, we proposed a possible mechanism for the photodecomposition of MB by ZnPc–SiO2–TiO2.