Rapid profiling of stress-response at single-cell resolution yet in a label-free, non-disruptive and mechanism-specific manner can lead to many new applications. We propose a single-cell-level biochemical fingerprinting approach named “ramanome”, which is the collection of Single-cell Raman Spectra (SCRS) from a number of cells randomly selected from an isogenic population at a given time and condition, to rapidly and quantitatively detect and characterize stress responses of cellular population. SCRS of Escherichia coli cells are sensitive to both exposure time (eight time points) and dosage (six doses) of ethanol, with detection time as early as 5 min and discrimination rate of either factor over 80%. Moreover, the ramanomes upon six chemical compounds from three categories, including antibiotics of ampicillin and kanamycin, alcohols of ethanol and n-butanol and heavy metals of Cu2+ and Cr6+, were analyzed and 31 marker Raman bands were revealed which distinguish stress-responses via cytotoxicity mechanism and variation of inter-cellular heterogeneity. Furthermore, specificity, reproducibility and mechanistic basis of ramanome were validated by tracking stress-induced dynamics of metabolites and by contrasting between cells with and without genes that convey stress resistance. Thus ramanome enables rapid prediction and mechanism-based screening of cytotoxicity and stress-response programs at single-cell resolution.
Dengue virus (DENV) has become a global health threat with about half of the world’s population at risk of infection. Although the disease caused by DENV is self-limiting in the first infection, the antibody-dependent enhancement (ADE) effect increases the mortality in the second infection with a heterotypic virus. Since there is no specific efficient medicine in treatment, it is urgent to develop vaccines to prevent infection and disease progression. Currently, only a live attenuated vaccine, chimeric yellow fever 17D—tetravalent dengue vaccine (CYD-TDV), has been licensed for clinical use in some countries, and many candidate vaccines are still under research and development. This review discusses the progress, strengths, and weaknesses of the five types of vaccines including live attenuated vaccine, inactivated virus vaccine, recombinant subunit vaccine, viral vectored vaccine, and DNA vaccine.
Here we demonstrate that a fluorescent benzothiadiazole (BTD)-conjugated terphenyldicarboxylate (TPDC) linker (denoted as H-ostpdc) has been hybridized by a quinoxaline-2,3-(1H,4H)-dione (QD) moiety possessing lactam-lactim tautomerism, which was further integrated into a robust and porous UiO-68 type zirconium metal-organic framework (MOF UiO-68-osdm) by utilizing the mixed two dicarboxylate struts with the same ligand lengths. The resultant MOF UiO-68-osdm can work as a ratiometric luminescent sensor for visual and selective detection of alkyl amines. Furthermore, it can discriminate secondary alkylamines from other type amine species.
Both the replication and transcription of the influenza virus are catalyzed by the viral polymerase complex. The polymerases of most avian influenza A viruses have poor performance in mammalian cells, which is considered to be one of the important species barriers. Pigs have been long considered as important intermediate hosts for interspecies transmission of the avian influenza virus, because of their susceptibility to infection with both avian and mammalian influenza viruses. However, the molecular basis of influenza polymerase adaptation in pigs remains largely unknown. ANP32A and ANP32B proteins have been identified as playing fundamental roles in influenza virus replication and host range determination. In this study, we found that swine ANP32A (swANP32A), unlike swine ANP32B or other mammalian ANP32A or B, shows stronger supporting activity to avian viral polymerase. Knockout of ANP32A in pig cells PK15 dramatically reduced avian influenza polymerase activity and viral infectivity, suggesting a unique feature of swANP32A in supporting avian influenza viral polymerase. This species-specific activity is mapped to two key sites, 106V and 156S, in swANP32A. Interestingly, the amino acid 106V is unique to pigs among all the vertebrate species studied, and when combined with 156S, exhibits positive epistasis in pigs. Mutation of 106V and 156S to the signature found in ANP32As from other mammalian species weakened the interaction between swANP32A and chicken viral polymerase, and reduced polymerase activity. Understanding the molecular basis of ANP32 proteins may help to discover new antiviral targets and design avian influenza resistant genome edited pigs.
Background: TANK is a negative regulator of canonical NF-B signaling. Results: EMCV 3C cleaves TANK and regulates NF-B activation. Conclusion: EMCV 3C relieves TANK inhibitory effect on TRAF6-mediated NF-B signaling pathway. Significance: TANK is a novel target protein of viral proteases encoded by several positive RNA viruses.
We aimed to analyze the outcomes of hypofractionated high-energy electron beam radiotherapy for the treatment of keloids. From February 1998 to January 2012, 568 patients with a total of 834 keloids underwent radiotherapy: 826 lesions with postoperative radiotherapy, and 36 with skin-grafting. Lesion size was >5 cm in 335 keloids. An electron-beam of 6 or 7 MeV was used, with a total dose of 18 Gy (two fractions with a 1-week interval) covering the lesion with a 1-cm margin. The time between surgery and radiotherapy was 24–48 h. Skin-grafted patients underwent radiotherapy 10–15 days after the operation. The median follow-up was 40 months (range: 12–160 months). The local control rate was 88.25% (736/834). The relapse rate was 9.59% (80/834), and the time to relapse was 6–28 months (median: 12 months). Univariate analyses showed that gender, age, keloid size, keloid site, skin grafting, and operation-to-irradiation interval influenced the local control rate. Multivariate analysis showed that the relapse rate was correlated with gender (P = 0.048), age (P < 0.01), operation-to-irradiation interval (P < 0.01), keloid site (P < 0.01), surgical method (P = 0.04) and keloid size (P < 0.02). Adverse effects were observed in 9.83% (82/834). No radiation-induced cancers were observed. Hypofractionated high-energy electron beam radiotherapy for keloids yielded excellent outcomes, especially in cases without skin grafting. Early postoperative radiotherapy with limited hypofractionation could be a good choice for keloid treatment.
A keloid scar is an overgrowth of dense fibrous tissue that develops around a wound. These scars are raised scars that spread beyong the margins of the orinigal wound to normal skin by invasion. Keloid tissue consists of both an epithelium and dermal fibroblasts. Recent studies have primarily focused on keloid fibroblasts; however, the precise role of keratinocytes in the invasion process of keloids remains to be identified. Hypoxia is a typical characteristic of keloid scars, as well as other solid tumors. The expression of the transcription factor, hypoxia-inducible factor-1α (HIF-1α), is mainly induced by hypoxia and is known for its ability to induce proliferative and transformative changes in cells; its expression has been shown to correlate with tumor invasion and metastasis. In the present study, we used immunohistochemistry, fluorescence staining and western blot analysis and demonstrated that HIF-1α was highly expressed in both the epithelial layer of keloid tissue specimens and in hypoxia-exposed keratinocytes, which suggested that the keloid keratinocytes underwent epithelial-to-mesenchymal transition (EMT) in vitro. The high expression of mesenchymal markers, such as as vimentin and fibronectin was confirmed, as well as the reduced expression of E-cadherin and zonula occludens-1 (ZO-1) during this process by detection at the protein and mRNA level. Moreover, siRNA targeting HIF-1α reversed the changes which had occurred in the morphology of the keratinocytes (cells had acquired a fibroblast-like appearance) and suppressed the invasive ability of the keratinocytes. In conclusion, the present findings demonstrate that the hypoxia/HIF-1α microenvironment provides a favorable environment for keloid-derived keratinocytes to adopt a fibroblast-like appearance through EMT. This transition may be responsible for the enhanced capacity of keloid keratinocytes to invade, allowing the keloids to extend beyond the wound margin.
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