Spliceosomal snRNAs, the Essential Players in pre-mRNA Processing in Eukaryotic Nucleus: From Biogenesis to Functions and Spatiotemporal Characteristics.

Spliceosomal small nuclear RNAs (snRNAs) are a fundamental class of non-coding small RNAs abundant in the nucleoplasm of eukaryotic cells, playing a crucial role in splicing precursor messenger RNAs (pre-mRNAs). They are transcribed by DNA-dependent RNA polymerase II (Pol II) or III (Pol III), and undergo subsequent processing and 3' end cleavage to become mature snRNAs. Numerous protein factors are involved in the transcription initiation, elongation, termination, splicing, cellular localization, and terminal modification processes of snRNAs. The transcription and processing of snRNAs are regulated spatiotemporally by various mechanisms, and the homeostatic balance of snRNAs within cells is of great significance for the growth and development of organisms. snRNAs assemble with specific accessory proteins to form small nuclear ribonucleoprotein particles (snRNPs) that are the basal components of spliceosomes responsible for pre-mRNA maturation. This article provides an overview of the biological functions, biosynthesis, terminal structure, and tissue-specific regulation of snRNAs.

[A preliminary study on shade matching ability of dental professionals with different background].

PURPOSE: To investigate the difference of shade matching ability of dental professionals with different educational background using toothguide training box (TTB), and provide information for medical esthetics course in dental school. METHODS: Sixty subjects including 20 dental students, 20 prosthodontics technical students and 20 prosthodontics technicians without color blindness were enrolled in this study. Each participant was asked to match 15 standard shade tabs which have been randomly chosen from Vita 3D-Master shade guide. SPSS 17.0 software package was used for data analysis. RESULTS: The scores of dental students, prosthodontics technical students and dental prosthodontics technicians were 834.04±51.66, 859.40±53.31and 888.36±48.54, respectively. There was no significant difference in the sum number of accurate shade matching compared between dental students and prosthodontics technical students (P>0.05), but there was significant difference between dental prosthodontics technicians, prosthodontics technical students (P<0.05), and dental students (P<0.01). CONCLUSIONS: The score of shade matching is significantly different among dental professionals with different background using TTB.

Local expression of secondary lymphoid tissue chemokine delivered by adeno-associated virus within the tumor bed stimulates strong anti-liver tumor immunity.

Development of an effective antitumor immune response depends on the appropriate interaction of effector and target cells. Thus, the expression of chemokines within the tumor may induce a more potent antitumor immune response. Secondary lymphoid tissue chemokine (SLC) is known to play a critical role in establishing a functional microenvironment in secondary lymphoid tissues. Its capacity to attract dendritic cells (DCs) and colocalize them with T cells makes it a good therapeutic candidate against cancer. In this study, we used SLC as a treatment for tumors established from a murine hepatocellular carcinoma model. SLC was encoded by recombinant adeno-associated virus (rAAV), a system chosen for the low host immunity and high efficiency of transduction, enabling long-term expression of the gene of interest. As a result, rAAV-SLC induced a significant delay of tumor progression, which was paralleled by a profound infiltration of DCs and activated CD4(+) T cells and CD8(+) T cells (CD3(+) CD69(+) cells) into the tumor site. In addition, rAAV-SLC treatment was also found to reduce tumor growth in nude mice, most likely due to inhibition of neoangiogenesis. In conclusion, local expression of SLC by rAAV represents a promising approach to induce immune-mediated regression of malignant tumors.