Evolution and structural variations in chloroplast tRNAs in gymnosperms.

BACKGROUND: Chloroplast transfer RNAs (tRNAs) can participate in various vital processes. Gymnosperms have important ecological and economic value, and they are the dominant species in forest ecosystems in the Northern Hemisphere. However, the evolution and structural changes in chloroplast tRNAs in gymnosperms remain largely unclear. RESULTS: In this study, we determined the nucleotide evolution, phylogenetic relationships, and structural variations in 1779 chloroplast tRNAs in gymnosperms. The numbers and types of tRNA genes present in the chloroplast genomes of different gymnosperms did not differ greatly, where the average number of tRNAs was 33 and the frequencies of occurrence for various types of tRNAs were generally consistent. Nearly half of the anticodons were absent. Molecular sequence variation analysis identified the conserved secondary structures of tRNAs. About a quarter of the tRNA genes were found to contain precoded 3' CCA tails. A few tRNAs have undergone novel structural changes that are closely related to their minimum free energy, and these structural changes affect the stability of the tRNAs. Phylogenetic analysis showed that tRNAs have evolved from multiple common ancestors. The transition rate was higher than the transversion rate in gymnosperm chloroplast tRNAs. More loss events than duplication events have occurred in gymnosperm chloroplast tRNAs during their evolutionary process. CONCLUSIONS: These findings provide novel insights into the molecular evolution and biological characteristics of chloroplast tRNAs in gymnosperms.

Characterization of the DNA molecular sequence of complete plastid genome of Paeonia rockii subsp. taibaishanica, an endemic species in China.

Paeonia rockii subsp. taibaishanica (Paeoniaceae), one of the tree peony species, is endemic to the Qinling Mountains in central China. In this study, we characterized its whole plastid genome sequence using the Illumina sequencing platform. The complete plastid genome size of P. rockii subsp. taibaishanica is 153,368 bp in length, including a large single copy (LSC) region of 85,030 bp, a small single copy (SSC) region of 17,042 bp, and a pair of inverted repeats (IRs) of 25,648 bp. The genome contains 131 genes, including 83 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. The GC contents in chloroplast genome, LSC region, SSC region, and IR region were 38.3%, 36.6%, 32.6%, and 43.1%, respectively. A total of 16 species are used to construct the phylogenetic tree of Paeoniaceae, the results showed that P. rockii subsp. taibaishanica is more closely related with congeneric Paeonia suffruticosa and Paeonia ostii, these species were clustered into a clade with high bootstrap support.

[Immunologic theory investigation and discussion of pain caused by lumbar intervertebral disc herniation (LDH)].

To explore the main clinical manifestation (lower back pain and ischialgia) of LDH with immunologic method and study the relationship and clinical significance of the cardinal symptom (pain) and immune comple (IC), macrophage (MP),interleukin-1 (IL-1), interleukin-6 (IL-6), tumor necrosis factor (TNF), prostaglandin E2 (PGE2), phosphatidase A2 (PLA2), nitrogen monoxidum (NO) expressing, finding a new way in order to prevention and cure of LDH. We will review immunologic theory of LDH pain.

[Investigations and analysis of traumatic condition of Longnan area in Wenchuan earthquake].

OBJECTIVE: To investigate and analyze the traumatic conditions of Longnan area of Gansu in Wenchuan earthquake, and to explore the measures coping with unexpected disasters. METHODS: A sample survey including questionnaire survey, interviews and other methods was adopted to investigate the conditions of affected population of Longnan area in earthquake, especially on the traumatic conditions, the injured causes, treatment methods. RESULTS: In the sample survey of a total of 1652 earthquake casualties, the dead were 16 and the patients with extremities fractures were 750 (45.4%). Organized and timely rescue of the wounded could reduce the complications and the mortality . CONCLUSION: Strengthening the prevention and treatment of earthquake trauma can effectively decrease the death rate and disabled rate.