Assessment of fish biodiversity in four Korean rivers using environmental DNA metabarcoding.

Environmental DNA (eDNA) metabarcoding is a cost-effective novel approach to estimate biodiversity in an ecosystem. In this study, the MiFish pipeline was employed to test if the system methodology is sufficiently reliable to estimate fish biodiversity in Korean rivers. A total of 125 unique haplotypes and 73 species were identified at the species level from 16 water samples collected from a single survey in four Korean rivers (Hyeongsan, Taehwa, Seomjin, and Nakdong). Among the four rivers, the highest species richness was recorded in the Seomjin River (52 species), followed by the Taehwa (42 species) and Hyeongsan (40 species) rivers. The Nakdong River (26 species) presented the lowest species richness and number of endemic species, presumably due to its metropolitan location and anthropogenic impacts, such as dams or weirs. We were also able to detect that five exotic species (Carassius cuvieri, Cyprinus carpio, Cyprinus megalophthalmus, Lepomis macrochirus, and Micropterus salmoides) are widely distributed in all surveyed rivers, a situation that might be problematic in terms of conservation. Our findings indicate that the eDNA metabarcoding technique is one of the most cost-effective scientific tools available for the management and conservation of the freshwater fish resources available in Korea. However, the low number of 12S sequences of endemic species in the database and low resolution of the MiFish region for differentiating several taxa should be upgraded for their wide use.

Characterization of complete mitochondrial genome of two-spot swimming crab Charybdis bimaculata (Miers, 1886).

The two-spot swimming crab Charybdis bimaculata (Miers, 1886) is an important decapod species in the benthic ecosystem of Korean waters. In this study, we determined its complete mitochondrial genome by the combination of NGS analysis using MiSeq platform and PCR-based cloning method. The circular mitochondrial genome of C. bimaculata was 15,714 bp in length in which the standard set of 13 protein-coding genes, 22 tRNA genes, and 2 rRNA genes were encoded. Phylogenic analysis showed that C.bimaculata is most closely related to Charybdis feriata. The complete mitogenome sequence information of C. bimaculata would provide useful data for the conservation of their population in the Pacific ocean.

The complete mitochondrial genome of the Argentine red shrimp Pleoticus muelleri (Bate, 1888) (Crustacea, Decapoda, Solenoceridae).

The complete mitochondrial genome of Argentine red shrimp, Pleoticus muelleri (Bate, 1888) was determined using the MiSeq platform. Its mitogenome (16,189 bp) encoded the canonical 13 protein-coding genes, 22 tRNA genes, two rRNA genes. Start codons of all protein-coding genes were ATN except for ATP8, while incomplete stop codons (T-) were identified in six genes including COXI, COXII, COXIII, NAD3, NAD5, and NAD6. The mitogenome of P. muelleri showed highest sequence identity with Parapenaeopsis hardwickii (82%) and Solenocera crassicornis (81%). Phylogenetic analysis showed three shrimps in Solenoceridae including P. muelleri were grouped together from those in Penaeidae, which suggests taxonomic reexamination for those in those family.

Characterization of the mitogenome of Cynoglossus Senegalensis (Pleuronectiformes: Cynoglossidae).

The complete mitogenome of the Senegalese tonguesole, Cynoglossus senegalensis was determined by Illumina MiSeq platform. The complete mitochondrial genome of C. senegalensis was 16,519 bp in length. The mitochondrial genome of C. senegalensis showed a cynoglosidae-characteristic gene organization, in which translocation of control region to the position between ND1 and tRNA-Gln gene, and also inversions in tRNA-Gln gene from L-strand position to H-strand position. Phylogenetic analysis showed that C. senegalensis is most closely related to C. sinicus and S.bilineatus, which supports the previous result that genus Cynoglossidae is evolutionary paraphyletic.

The complete mitogenome of Bagrid catfish Chrysichthys nigrodigitatus (Siluriformes: Claroteidae).

We here report the complete mitochondrial genome of Chrysichthys nigrodigitatus, which is 16,514 bp in length. Mitogenome of C. nigrodigitatus showed the conserved 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and two noncoding regions including the light-strand replication origin (OL) and a putative control region (CR). All tRNA genes were predicted to fold into the typical cloverleaf secondary structures with the typical base-pairing except for tRNA-Ser(AGC). Phylogenetic analysis with currently known complete mitogenome sequences in Siluriformes showed that C. nigrodigitatus is most closely related to Auchenoglanis occidentalis forming a family Claroteidae cluster.

Uterine restoration after repeated sloughing of fibroids or vaginal expulsion following uterine artery embolization.

The aim of our study is to present our experience with uterine restoration after repeated sloughing of uterine fibroids or transvaginal expulsion following uterine artery embolization (UAE) and to determine its safety and outcome. One hundred and twenty-four women (mean age, 40.3 years; age range, 29-52 years) with symptomatic uterine fibroids were included in this retrospective study. We performed arterial embolization with poly(vinyl alcohol) particles (250-710 microm). Clinical symptoms and follow-up information for each patient were obtained through medical records. At an average of 3.5 months (range, 1-8 months) after embolization, magnetic resonance imaging examinations with T1- and T2-weighted and gadolinium-enhanced T1-weighted images were obtained for all patients. The mean follow-up duration was 120 days (90-240 days). Eight (6.5%) patients experienced uterine restoration after repeated sloughing of uterine fibroids or spontaneous transvaginal expulsion. The locations of the leiomyomas were submucosal (n=5), intramural (n=2) and transmural (n=1). The maximum diameter of the fibroids ranged from 3.5 to 18.0 cm, with a mean of 8.4 cm. The time interval from embolization to the uterine restoration was 7-150 days (mean 70.5 days). The clinical symptoms before and during vaginal sloughing or expulsion were lower abdominal pain (n=4), vaginal discharges (n=3), infection of necrotic myomas (n=2) and cramping abdominal pain (n=1). Gentle abdominal compression (n=1) and hysteroscopic assistance (n=1) were required to remove the whole fibroid. No other clinical sequelae, either early or delayed, were documented. Magnetic resonance images revealed the disappearance of leiomyomas, intracavitary rupture resulting in transformation of intramural or transmural myomas into submucosal myomas and localized uterine wall defects. Although the small size of this study precludes a strict conclusion, there appear to be few serious complications directly related to vaginal expulsion. Vaginal expulsion or fibroid sloughing is a possible course following UAE that is manageable, and the patients should be informed about this possibility.