Circular RNAs in pulmonary hypertension:Emerging biological concepts and potential mechanism

Circular RNAs(circRNAs)are endogenous RNAs with a covalently closed single-stranded transcript.They are a novel class of genomic regulators that are linked to many important development and disease processes and are being pursued as clinical and therapeutic targets.Using the most powerful RNA sequencing and bioinformatics techniques,a large number of circRNAs have been identified and further functional studies have been performed.It is known that circRNAs act as potential biomarkers,sponges for microRNAs(miRNAs)and RNA-binding proteins(RBPs),and regulators of mRNA transcription.They also participate in the translation of peptides or proteins.Many types of circRNAs are dysregulated in plasma or lung tissues,and they may be involved in regulating the proliferation and apoptosis of pulmonary artery endothelial cells(PAECs)and pulmonary artery smooth muscle cells(PASMCs),leading to pulmonary vascular remodeling in pulmonary hypertension(PH).One possible mechanism is that circRNAs can regulate the function of PAECs and PASMCs by acting as miRNA sponge.However,other potential mechanisms of action of circRNAs are still being actively explored in PH.This paper presents a systematic review of the biogenesis,biological characterization,relevant underlying functions,and future perspectives for studies of circRNAs in the pathogenesis of PH.

Detection and characterization of an isolate of Tomato mottle mosaic virus infecting tomato in China

Tomato（Solanum lycopersicum） plants exhibiting severe leaf distortion, mottle and systemic crinkling symptoms were identified in Hainan province in China in 2016. To survey and control the disease, it is necessary to identify and characterize the pathogen causing the disease. Dot enzyme-linked immunosorbent assay showed that the crude saps of the infected tomato samples reacted positively with the monoclonal antibody against Tobacco mosaic virus which indicated that one or more tobamoviruses are likely associated with the disease. RT-p CR and DNA sequence analysis results further elucidated that Tomato mottle mosaic virus（To MMV） in Tobamovirus was the pathogen causing the mottle disease in tomato. We amplified and sequenced the full-length sequence of the genome which showed the highest nucleotide identity with To MMV YYMLJ and To MMV Ti Lha LJ isolates. The putative virus isolate was named To MMV Hainan. Biological indexing studies showed that To MMV Hainan can infect Nicotiana benthamiana, Capsicum annuum and Solanum lycopersicum showing serious symptoms. This was the first identification and characterization of To MMV infecting tomato in Hainan of China.

Study on biological characters of SGC7901 gastric cancer cell-dendritic cell fusion vaccines

AIM： To detect the biological characters of the SGC7901 gastric cancer cell-dendritic cell fusion vaccines.METHODS： The suspending living SGC7901 gastric cancer cells and dendritic cells were induced to be fusioned by polyethylene glycol. Pure fusion cells were obtained by selective culture with the HAT/HT culture systems. The fusion cells were counted at different time points of culture and their growth curves were drawn to reflect their proliferative activities. The fusion cells were also cultured in culture medium to investigate whether they could grow into cell clones. MTT method was used to test the stimulating abilities of the fusion cells on T lymphocytes＇ proliferations. Moreover, the fusion cells were planted into nude mice to observe whether they could grow into new planted tumors in this kind of immunodeficiency animals.RESULTS： The fusion cells had weaker proliferative activity and clone abilities than their parental cells. When they were cultured, the counts of cells did not increase remarkably, nor could they grow into cell clones in culture medium. The fusion cells could not grow into new planted tumors after planted into nude mice. The stimulating abilities of the fusion cells on T lymphocytes＇ proliferations were remarkably increased than their parental dendritic cells. CONCLUSION： The SGC7901 gastric cancer cell-dendritic cell fusion vaccines have much weaker proliferative abilities than their parental cells, but they keep strong abilities to irritate the T lymphocytes and have no abilities to grow into new planted tumors in immunodeficiency animals. These are the biological basis for their antitumor biotherapies.

Observation of Biological Character of Drosophila melanogaster Meigen on Cherry and Screening of Its Insecticides

Indoor rearing observation and efficacy test of insecticides were conducted in 2010 to understand the biochemical characteristics of Drosophila rnelano-gaster and high efficient insecticides against the insect pest. The results showed that D. melanogaster had preference to eight kinds of fruits with proliferation. Fe-male adults of D. melanogaster laid eggs under epidermis of cherry fruits and newly hatched larvae caused damage on fruits. When the temperatures were （ 18 ±2） ℃ and （ 23 ± 2 ） ℃, the egg stage was 2.4 - 3.0 and 1.2 - 1.8 d ; the larval stage was 11.2 - 12.2 and 5.6 - 6.5 d; the papal stage was 9.5 - 10.6 and 5.0 - 6.2 d ; one generation was 23.1 - 25.4 and 12.8 - 14.2 d, respectively. Four insecticides （ including 1% emamectin benzoate EC 3 000 times dilution, 90% crys- tal trichlorfon 1 000 times dilution, 40% phoxim EC 1 500 times dilution and 25% buprofezin WP 2 000 times dilution） had higher control effects against D. mela-nogaster, with mortalities of 85.00% - 100.00%, 96.67% - 100.00% and 100.00% after insecticide application for 1, 3 and 6 h, respectively.

Review on studies of Eupatorium adenophorum--an important invasive species in China

Eupatorium adenophorum Spreng. was introduced in Yunnan Province of China around 1940. Since then it has been spreading rapidly, particularly in the southern and southwestern parts of China and caused serious economic loss. The biological research and inte-grated control on E. adenophorum were carried out from 1980's in Yunnan Province. Together with other 15 invasive external species, the weed has been listed in the White Paper by The State Environmental Protection Administration of China. This paper briefly reviews the studies on natural distribution, biological character, ecological character, chemical component, hazard, potential application and the control of E. adenophorum. The research direction for this invasive external species in future was also discussed.

Biological and biochemical characterization of a red-eye mutant in Nilaparvata lugens （Hemiptera： Delphacidae）

A red-eye colony was established in our laboratory in brown planthopper （BPH）, Nilaparvata lugens （Stal）, a major rice pest in Asia. Except for the red-eye phenotype, no other differences were observed between the wild-type （brown eye） and the mutant-type （red eye） in external characters. Genetic analysis revealed that the red-eye phenotype was controlled by a single autosomal recessive allele. Biological studies found that egg produc- tion and egg viability in the red-eye mutant colony were not significantly different from those in the wild-type BPH. Biochemical analysis and electronic microscopy examination revealed that the red-eye mutants contained decreased levels of both xanthommatin （brown） and pteridine （red） and reduced number of pigment granules. Thus, the changes of amount and ratio of the two pigments is the biochemical basis of this red-eye mutation. Our results indicate that the red-eye mutant gene （red） might be involved in one common gene locus shared by the two pigments in pigment transportation, pigment granule formation or some other processes.

Biological character of human adipose-derived adult stem cells and influence of donor age on cell replication in culture

To investigate the biological character of human adipose-derived adult stem cells (hADAS cells) when cultured in vitro and the relationship between hADAS cell’s replication activity and the donor’s age factor, and to assess the stem cells as a new source for tissue engineering. hADAS cells are isolated from human adipose tissue of different age groups (from adolescents to olds: <20 years old, 21―40 years old, 41―60 years old and >61 years old groups). The protein markers (CD29, CD34, CD44, CD45, CD49d, HLA-DR, CD106) of hADAS cells were detected by flow cytometry (FCM) to identify the stem cell, and the cell cycle was examined for P20 hADAS cells to evaluate the safety of the subculture in vitro. The generative activity of hADAS cells in different age groups was also examined by MTT method. The formula “ log2T D = t logN t ? logN 0” was used to get the time doubling (TD) of the cells. The results showed that the cells kept heredity stabilization by chromosome analysis for at least 20 passages. The TD of these cells increased progressively by ageing, and the TD of the <20 years old group was lower than that of the >61 years old group (statistical analysis of variance (ANOVA), P=0.002, P<0.05). These find- ings suggested that a higher level of hADAS cells replication activity was found in the younger dona- tors, and they represent novel and valuable seed cells for studies of tissue engineering.