Background dementia has been a major public health problem. However, there has not yet been a nationwide investigation or systematic analysis of the prevalence of dementia in China from 1980 to 2004. Objectives the aim of this study was to analyse the prevalence of dementia and its major subtypes [Alzheimer disease (AD), vascular dementia (VD)] among the population aged 60 years and older in China from 1980 to 2004. Methods epidemiological investigations on dementia in China published in journals and covering the period from 1980 to 2004 were identified manually and on-line by using CBMDISK, Chongqing VIP database and CNKI database. Those reported in English journals were identified using MEDLINE. Selected studies had to describe an original study defined by strict screening and diagnostic criteria. The fixed effects model or random effects model was employed according to statistical test for homogeneity. Results twenty-five studies were selected, the statistical information of which was collected for systematic analysis. Our results showed that AD and VD were the two major subtypes of dementia in China, and the pooled prevalence of AD and VD for the population aged 60 years and older was 1.6 and 0.8%, respectively. There was a higher prevalence of AD in the illiterate elderly population (3.2%) than in those who received years of education. The chronological prevalence of AD increased significantly from 1980 to 2004. In southern and northern China, the prevalence of AD was 2.0 and 1.2%, respectively, while VD was 0.6 and 1.1%, respectively. Conclusions in the last 24 years, AD and VD were the two major subtypes of dementia in China. The prevalence of AD may be affected by sex, education, occupation or age. The prevalence of VD, which was higher in northern than in southern China, seems not to be affected by age, sex or education.

Porcine reproductive and respiratory syndrome virus (PRRSV) and transmissible gastroenteritis virus (TGEV) are two highly infectious and lethal viruses causing major economic losses to pig production. Here, we report generation of double-gene-knockout (DKO) pigs harboring edited knockout alleles for known receptor proteins CD163 and pAPN and show that DKO pigs are completely resistant to genotype 2 PRRSV and TGEV. We found no differences in meat-production or reproductive-performance traits between wild-type and DKO pigs, but detected increased iron in DKO muscle. Additional infection challenge experiments showed that DKO pigs exhibited decreased susceptibility to porcine deltacoronavirus (PDCoV), thus offering unprecedented in vivo evidence of pAPN as one of PDCoV receptors. Beyond showing that multiple gene edits can be combined in a livestock animal to achieve simultaneous resistance to two major viruses, our study introduces a valuable model for investigating infection mechanisms of porcine pathogenic viruses that exploit pAPN or CD163 for entry.

Two types of carbon dots were prepared by using the powder of young barley leaves as the precursor, which have the capability of selective cell imaging and antiviral activity.

Transmissible gastroenteritis virus (TGEV), an enteropathogenic coronavirus (CoV) of porcine, causes lethal watery diarrhea and severe dehydration in piglets and leads to severe economic losses in the swine industry. Unlike most CoVs that antagonize type I interferon (IFN) production, previous studies showed that TGEV infection induces IFN-I production both in vivo and in vitro. However, the underlying mechanism(s) remain largely unknown. In this study, we found that TGEV infection significantly facilitated IFN-β production as well as activation of the transcription factors IFN regulatory factor 3 (IRF3) and nuclear factor-kappaB (NF-κB) in porcine kidney (PK-15) cells. Screening of TGEV-encoded proteins demonstrated that non-structural protein 14 (nsp14) was the most potent IFN-β inducer and induced IFN-β production mainly by activating NF-κB but not IRF3. Further analysis showed that nsp14 interacted with DDX1, a member of the DExD/H helicase family. Knockdown of DDX1 by specific small interfering RNA (siRNA) significantly decreased nsp14-induced IFN-β production and NF-κB activation. Furthermore, TGEV-induced IFN-β production and IFN-stimulated gene (ISG) expression were decreased in cells transfected with DDX1-specific siRNA, indicating the vital role of DDX1 to TGEV-induced IFN-β responses. In summary, our data revealed a potential coactivator role of host RNA helicase DDX1 to the induction of IFN-β response initiated by TGEV and demonstrated that nsp14 is an important IFN inducer among the TGEV-encoded proteins.

Tumor development has long been known to resemble abnormal embryogenesis. The ESC self-renewal gene NANOG is purportedly expressed in some epithelial cancer cells and solid tumors, but a casual role in tumor development has remained unclear. In order to more comprehensively elucidate the relationship between human Nanog and tumorigenesis, the hNanog was ectopically expressed in the 293 cell line to investigate its potential for malignant transformation of cells both in vitro and in vivo. Here we provide compelling evidence that the overexpression of hNanog resulted in increased cell proliferation, anchor-independent growth in soft agar, and formation of tumors after subcutaneous injection of athymic nude mice. Pathologic analysis revealed that these tumors were poorly differentiated. In analysis of the underlying molecular mechanism, two proteins, FAK and Ezrin, were identified to be upregulated in the hNanog expressing 293 cells. Our results demonstrate that hNanog is a potent human oncogene and has the ability to induce cellular transformation of human cells.