Stimulated emission depletion microscopy provides a powerful sub-diffraction imaging modality for life science studies. Conventionally, stimulated emission depletion requires a relatively high light intensity to obtain an adequate depletion efficiency through only light–matter interaction. Here we show efficient emission depletion for a class of lanthanide-doped upconversion nanoparticles with the assistance of interionic cross relaxation, which significantly lowers the laser intensity requirements of optical depletion. We demonstrate two-color super-resolution imaging using upconversion nanoparticles (resolution ~ 66 nm) with a single pair of excitation/depletion beams. In addition, we show super-resolution imaging of immunostained cytoskeleton structures of fixed cells (resolution ~ 82 nm) using upconversion nanoparticles. These achievements provide a new perspective for the development of photoswitchable luminescent probes and will broaden the applications of lanthanide-doped nanoparticles for sub-diffraction microscopic imaging.

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Hepatitis B virus (HBV) mutations and signal transducer and activator of transcription 3 (STAT3) activation are closely associated with hepatocellular carcinoma (HCC). However, single nucleotide polymorphisms (SNPs) of STAT3 have not been implicated in HCC susceptibility. This study was designed to evaluate the effect of STAT3 SNPs and their interactions with HBV mutations on HCC risk. A total of 2,011 HBV-infected subjects (including 1,021 HCC patients) and 1,012 healthy controls were involved in this study. SNPs rs4796793 (21697, C>G), rs2293152 (intron 11, C>G), and rs1053004 (3 0 untranslated region, T>C) were genotyped using quantitative polymerase chain reaction. HBV mutations were determined via direct sequencing. It was found that rs2293152 (GG versus CC) was significantly associated with HCC risk compared with the subjects without HCC, adjusting for age and sex (adjusted odds ratio [AOR], 1.30; 95% confidence interval [CI], 1.04-1.62). The impact of rs2293152 was greater in women compared with men. Compared with HCC-free HBV-infected subjects, rs2293152 GG was solely associated with HCC in women (AOR, 2.04; 95% CI, 1.15-3.61). rs2293152 GG was significantly associated with high viral load (!1 3 10 4 copies/mL) (AOR, 1.37; 95%, CI 1.01-1.88) and increased frequencies of T1674C/G (AOR, 1.61; 95% CI, 1.06-2.46) and A1762T/ G1764A (AOR, 1.64; 95% CI, 1.14-2.35). In multivariate regression analyses, multiplicative interaction of rs1053004 with T1674C/G significantly increased HCC risk, whereas rs2293152 and A1726C interaction reduced it, adjusting for covariates including HBV mutations in the enhancer II/basal core promoter/precore region; the interaction of rs4796793 with preS2 start codon mutation significantly increased HCC risk, adjusting for covariates including HBV mutations in the preS region. Conclusion: STAT3 SNPs appear to predispose the host with HBV mutations to hepatocarcinogenesis, and this effect may differ in men versus women. STAT3 SNPs may have applicability in future HCC surveillance algorithms. (HEPATOLOGY 2013; 57:2369-2377 L iver cancer in males is the fifth most frequently diagnosed cancer and the second most frequent cause of cancer-related death; in females, it is the seventh most commonly diagnosed cancer and the sixth leading cause of cancer death worldwide.1 Hepatocellular carcinoma (HCC) accounts for 70% to 85% of the total liver cancer burden.1 The highest HCC incidence rates are found in East and Southeast Asia and in sub-Saharan Africa. The rate is three-fold higher in males than in females. Chronic infection with hepatitis B virus (HBV) or hepatitis C virus (HCV), aflatoxin B1 exposure, alcohol drinking,

Background: SARS-CoV-2-caused coronavirus disease (COVID-19) is posing a large casualty. The features of COVID-19 patients with and without pneumonia, SARS-CoV-2 transmissibility in asymptomatic carriers, and factors predicting disease progression remain unknown. Methods: We collected information on clinical characteristics, exposure history, and laboratory examinations of all laboratory-confirmed COVID-19 patients admitted to PLA General Hospital. Cox regression analysis was applied to identify prognostic factors. The last follow-up was February 18, 2020. Results: We characterized 55 consecutive COVID-19 patients. The mean incubation was 8.42 (95% confidence interval [CI], 6.55-10.29) days. The mean SARS-CoV-2-positive duration from first positive test to conversion was 9.71 (95%CI, 8.21-11.22) days. COVID-19 course was approximately 2 weeks. Asymptomatic carriers might transmit SARS-CoV-2. Compared to patients without pneumonia, those with pneumonia were 15 years older and had a higher rate of hypertension, higher frequencies of having a fever and cough, and higher levels of interleukin-6 (14.61 vs. 8.06pg/mL, P=0.040), B lymphocyte proportion (13.0% vs.10.0%, P=0.024), low account (<190/µL) of CD8 + T cells (33.3% vs. 0, P=0.019). Multivariate Cox regression analysis indicated that circulating interleukin-6 and lactate independently predicted COVID-19 progression, with a hazard ratio (95%CI) of 1.052 (1.000-1.107) and 1.082 (1.013-1.155), respectively. During disease course, T lymphocytes were .CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.(which was not peer-reviewed) The copyright holder for this preprint .

c Genetic polymorphisms of HLA-DP have been associated with hepatitis B virus (HBV) persistence. We aimed to determine the effect of HLA-DP polymorphisms on the generation of HBV mutations and their interactions on the outcomes of HBV infection. rs3077, rs3135021, rs9277535, and rs2281388 were genotyped in 1,342 healthy controls, 327 HBV clearance subjects, and 2,736 HBV-positive subjects, including 1,108 hepatocellular carcinoma (HCC) patients, using quantitative PCR. HBV mutations were determined by sequencing. Multiplicative interactions of HLA-DP polymorphisms and viral mutations were assessed by multivariate logistic regression. rs3077 (from subjects with genotype CT combined with those from subjects with genotype TT [CT؉TT] versus CC), rs3135021 (GA؉AA versus GG), rs9277535 (GA؉AA versus GG), and rs2281388 (CC versus CT؉TT) significantly decreased HBV persistence. This effect was found only in genotype B HBV-infected subjects compared to HBV clearance subjects. HLA-DP polymorphisms promoting HBV clearance were associated with a lower prevalence of mutations increasing HCC risk (C1653T, T1674C/G, A1846T, G1896A and pre-S2 mutations and pre-S deletion in genotype C) and a higher prevalence of mutations decreasing HCC risk (G1652A, T1673C, T1674C, G1719T, G1730C, and G1799C in genotype B and A1727T in genotype C). Significant effects of viral mutations on cirrhosis and HCC were selectively evident in those with HLA-DP polymorphisms promoting HBV persistence. The interactions of C1653T, T1674C/G, and G1896A mutations with HLA-DP polymorphisms promoting HBV clearance significantly decreased cirrhosis risk. The interaction of rs9277535 AA with the T1674C/G or G1719T mutation in genotype C significantly decreased HCC risk. In conclusion, HLA-DP polymorphisms affect genotype B HBV clearance, regulate immune selection of viral mutations, and influence cirrhosis and HCC risks contributed by HBV mutations. Chronic infection with hepatitis B virus (HBV) currently affects 350 million to 400 million people worldwide, and over 200,000 and 300,000 HBV-infected subjects die from decompensated hepatic cirrhosis (HC) and hepatocellular carcinoma (HCC), respectively, each year (1, 2). Chronic HBV infection results in approximately one-third of all HC cases and more than one-half of all HCC cases worldwide (3). The World Health Organization includes HBV in "group 1" human carcinogens (4). According to a sequence divergence of Ͼ8% in the entire genome, HBV has been classified into at least 8 genotypes so far. HBV genotypes have distinct geographic distributions and have been shown to differ with regard to clinical liver diseases, outcomes, and responses to interferon treatment (5). In East Asia, where HBV genotypes B and C are endemic, viral factors of HBV, including genotype C infection, hepatitis B virus e antigen (HBeAg) expression, high viral load (Ͼ10 4 copies/ml), and mutations in the enhancer II/basal core promoter/precore (EnhII/BCP/PC) and the pre-S regions, as well as active hepatic inflammation contribute greatly to ...

BackgroundGenetic polymorphisms of pri-miR-34b/c and pre-miR-196a2 have been reported to be associated with the susceptibility to cancers. However, the effect of these polymorphisms and their interactions with hepatitis B virus (HBV) mutations on the development of hepatocellular carcinoma (HCC) remains largely unknown. We hypothesized that these polymorphisms might interact with the HBV mutations and play a role in hepatocarcinogenesis.Methods Pri-miR-34b/c rs4938723 (T>C) and pre-miR-196a2 rs11614913 (T>C) were genotyped in 3,325 subjects including 1,021 HBV-HCC patients using quantitative PCR. HBV mutations were determined by direct sequencing. Contributions of the polymorphisms and their multiplicative interactions with gender or HCC-related HBV mutations to HCC risk were assessed using multivariate regression analyses.Resultsrs4938723 CC genotype was significantly associated with HCC risk compared to HBV natural clearance subjects, adjusted for age and gender (adjusted odds ratio [AOR] = 2.01, 95% confidence interval [CI] = 1.16–3.49). rs4938723 variant genotypes in dominant model significantly increased HCC risk in women, compared to female healthy controls (AOR = 1.85, 95% CI = 1.20–2.84) or female HCC-free subjects (AOR = 1.62, 95% CI = 1.14–2.31). rs4938723 CC genotype and rs11614913 TC genotype were significantly associated with increased frequencies of the HCC-related HBV mutations T1674C/G and G1896A, respectively. rs11614913 was not significantly associated with HCC risk, but its CC genotype significantly enhanced the effect of rs4938723 in women. In multivariate regression analyses, rs4938723 in dominant model increased HCC risk (AOR = 1.62, 95% CI = 1.05–2.49), whereas its multiplicative interaction with C1730G, a HBV mutation inversely associated with HCC risk, reduced HCC risk (AOR = 0.34, 95% CI = 0.15–0.81); rs11614913 strengthened the G1896A effect but attenuated the A3120G/T effect on HCC risk.Conclusionsrs4938723 might be a genetic risk factor of HCC but its effect on HCC is significantly affected by the HBV mutations. rs11614913 might not be a HCC susceptible factor but it might affect the effects of the HBV mutations or rs4938723 on HCC risk.

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We aimed to evaluate whether hepatitis B virus (HBV) mutations at the core promoter region could improve the prediction and specific prophylaxis of hepatocellular carcinoma (HCC) in chronic HBV-infected patients. A total of 2,114 HBV-infected patients enrolled between August 1998 and December 2007 were followed-up for 18,406 person-years. Of those, 612 received !48 week treatments with nucleos(t)ide analogue (NA) and/or IFNa.