RESUMEN
Chimonanthus praecox, a member of the Calycanthaceae family, is a unique, traditional, and famous flowering economic tree species in China. Despite the existence of several varieties, only a few cultivars have been formally named. Currently, expression sequence tag-simple sequence repeat (EST-SSR) markers are extensively used to identify different species and varieties; a large number of microsatellites can be identified from transcriptome databases. A total of 162,638 unigenes were assembled using RNA-seq; 82,778 unigenes were annotated using the Nr, Nt, Swiss-Prot, Pfam, GO, KOG, and KEGG databases. In total, 13,556 SSR loci were detected from 11,691 unigenes, with trinucleotide repeat motifs being the most abundant among the six repeat motifs. To develop the markers, 64,440 pairs of SSR primers with polymorphism potential were designed, and 75 pairs of primers were randomly selected for amplification. Among these markers, seven pairs produced amplified fragments of the expected size with high polymorphism. Using these markers, 12 C. praecox varieties were clustered into two monophyletic clades. Microsatellites in the transcriptome of C. praecox exhibit rich types, strong specificity, and great polymorphism potential. These EST-SSR markers serve as molecular technical methods for identifying different varieties of C. praecox and facilitate the exploration of a large number of candidate genes associated with important traits.
RESUMEN
BACKGROUND: Extracranial internal carotid artery (eICA) tortuosity may trigger cerebral ischemia, and body mass index (BMI) is a measure of body mass based on height and weight. The main purpose of this study is to determine the influence of BMI on the tortuosity of eICA. METHODS: A total of 926 carotid artery angiograms were performed in 513 patients, of which 116 cases and matched controls were selected. Arterial tortuosity was defined as simple tortuosity, kinking, or coiling. The severity of tortuosity was measured by tortuosity index, formula: [(actual length/straight-line length - 1) × 100]. RESULTS: BMIs were different between the two groups [tortuosity: 27.06 kg/m2 (SD 2.81 kg/m2) versus none: 23.3 kg/m2 (SD 2.78 kg/m2); p < 0.001]. BMI was independently and significantly associated with eICA tortuosity (odds ratio 1.59; 95% confidence interval, 1.35-1.86; p < 0.001). eICA tortuosity index is linearly associated with BMI (exponential coefficient ß = 1.067, p < 0.001). The optimal predictive threshold of BMI for eICA tortuosity was 25.04 kg/m2. The physiological mechanism underlying the reasons why higher BMI has negative influence on extracranial carotid artery tortuosity may be an intra-abdominal hypertension caused by a much higher amount of body fat stored in visceral adipose tissue. CONCLUSION: Our result reveals a novel role for greater BMI on the presence of eICA tortuosity. For each increase in BMI of 1 kg/m2, there is a corresponding 1.59-fold increase in the risk of developing eICA tortuosity. The severity of eICA tortuosity increases linearly with increased BMI.