Insulin-like growth factor I of Japanese eel, Anguilla japonica: cDNA cloning, tissue distribution, and expression after treatment with growth hormone and seawater acclimation

In an attempt to understand growth regulation in the Japanese eel, Anguilla japonica, we cloned insulin-like growth factor-I (IGF-I) cDNAs and examined their mRNA expression in several tissues. Two eel IGF-I (eIGF-I) cDNAs encoding preprohormones, eIGF-I-Ea1and eIGF-I-Ea2, were cloned from the liver by polymerase chain reaction (PCR). The preproIGF-Is were identical in signal peptide and mature IGF-I, but different in the E domain—eIGF-I-Ea2 mRNA was 36 bp longer than eIGF-I-Ea1 mRNA. Eel IGF-I was 83–94% identical with that of teleosts, 71% identical with that of dogfish, 87% identical with that of bullfrog and chicken, and 83% identical with that of humans. In both males and females the highest eIGF-I-Ea1 mRNA levels were observed in the liver, with detectable levels also found in the gills, heart, stomach, spleen, kidney, intestine, swim-bladder, muscle, and gonads. eIGF-I-Ea1 mRNA levels in the liver were higher in females than in males whereas in the intestine they were lower than in males. eIGF-I-Ea2 mRNA was detected in all the tissues examined and at similar levels in males and females. In this experiment higher eIGF-I-Ea1 mRNA levels were observed in the liver of larger glass eels than in those of smaller fish. eIGF-I-Ea2 mRNA levels were also higher in larger eels, although they were lower than IGF-I-Ea1 mRNA levels. Both eIGF-I mRNA levels in liver were positively correlated with the body size of the␣glass eels. Intraperitoneal injection of recombinant eel GH (reGH), 0.25 μg g⁻¹ body weight, into glass eels resulted in a significant increase in both eIGF-I mRNAs in the liver 1 day after injection compared with control fish, but no elevation was observed 2 days after injection. Incubation of liver slices with reGH at concentrations of 10, 100, and 1,000 ng mL⁻¹ for 24 h resulted in a significant concentration-dependent increase in the levels of both eIGF-I mRNAs. Higher levels of eIGF-I-Ea1 and Ea2 mRNA were observed in the gills ofseawater-reared eels than in those of freshwater-reared fish, but no differenceswere observed in the whole kidney. These results suggest that IGF-I is involved in the regulation of somatic growth and also in adaptation of the Japanese eel to seawater.     

Hatch timing of two subarctic salmonids in a stream network estimated by otolith increments

Hatch timing in autumn-spawning stream salmonids is poorly understood in the subarctic region because snow cover prevents direct sampling of cryptic early life stages. Otolith micro-increment analysis was used to infer hatch dates of white-spotted charr Salvelinus leucomaenis (Pallas) and masu salmon Oncorhynchus masou (Brevoort) in a mainstem-tributary network in northern Japan. Accuracy and precision were validated by ageing hatchery individuals with known hatch date ranges. In July 2018, 93 wild young-of-the-year white-spotted charr and 81 masu salmon were collected and aged. Masu salmon hatched, on average, 24 days earlier (mean = February 8) than white-spotted charr (March 4), and hatch dates spanned a minimum of 2 months for each species. In masu salmon, hatch dates of individuals collected in the mainstem were nearly 3 weeks earlier than those in a tributary. This study provided knowledge on intra- and inter-specific variation in hatch timing of native salmonids in a subarctic stream network.     

Comparative study of anti-oncogenic microRNA-145 in canine and human malignant melanoma

MicroRNA-145 (miRNA-145; miR-145) is aberrantly expressed in most of human cancers and plays a significant role in carcinogenesis and cancer progression. In the current study, we focused on how miR-145 plays a role in canine and human malignant melanomas. MiR-145 was significantly downregulated in canine malignant melanoma tissues and canine melanoma cell lines, as well as human melanoma cell lines tested. The ectopic expression of miR-145 showed a significant growth inhibition in both canine and human melanoma cells tested, and the effect was achieved partly by suppressing c-MYC in canine melanoma LMeC and in human melanoma A2058 and Mewo cells. At the same time, a suppressive tendency on cell migration in canine melanoma KMeC cells and significant suppression of cell migration in human melanoma A2058 cells by suppressing FASCIN1 were also found. These findings suggest that miR-145 acts as a tumor suppressor in both canine and human malignant melanomas.     

Development of a rice herbicide,fenquinotrione

Fenquinotrione is a novel rice herbicide that was discovered and developed by Kumiai Chemical Industry Co., Ltd. It can control a wide range of broadleaf and sedge weeds with excellent rice selectivity at 30 g a.i./10 a and is as effective as the wild type on acetolactate synthase inhibitor-resistant weeds. Our metabolic and molecular biological studies showed that CYP81A6-mediated demethylation and subsequent glucose conjugation are responsible for the safety of fenquinotrione in rice. Fenquinotrione was registered in Japan in 2018, and various products containing fenquinotrione have been launched. With its high efficacy and excellent rice selectivity, we believe that fenquinotrione will contribute to efficient food production in the future.     

The Effect of Different Dietary Energy Levels on Growth and Survival of Eyestalk Ablated and Intact Juvenile Lobsters Homarus americanus

When fed formulated diets containing 45% protein derived from the rock crab Cancer irroratus , wheat gluten, gelatin, lipids adjusted from 3–14% and carbohydrates adjusted from 5–24%, the average survival of bilaterally eyestalk ablated juvenile lobsters and intact controls were 91% and 99%, respectively over a 90-day experiment. Photopenad (13 light: 11 dark vs 3 light: 21 dark) did not have a significant effect on growth or survival of ablated or intact lobsters. The optimal digestible energy levels and protein/energy ratio for the greatest growth in both ablated and intact lobsters were 3.7 to 3.8 (kcal/g dry) and 0.12 [g protein/(kcal/g)], respectively. The best feed conversion ratios (0.97 and 1.40 diet given/weight gain) for ablated and intact lobsters were obtained with diets containing 3.83 kcal/g and 3.63 kcal/g diet, respectively. The present study also demonstrated that crab protein served as a good protein source for intact and ablated lobsters.     

Cinnamaldehyde inhibits enzymatic browning of cut lettuce by repressing the induction of phenylalanine ammonia-lyase without promotion of microbial growth

Cinnamaldehyde treatment inhibited the browning of cut lettuce during cold storage. In this study, to clarify the mechanism of inhibitory action of cinnamaldehyde against the browning and to show its microbiological merit, its effect on the browning of cut lettuce was compared to that of mild heat treatment. Both cinnamaldehyde and mild heat treatments inhibited the induction of phenylalanine ammonia-lyase (PAL) activity because of cutting. As a result, the biosynthesis of polyphenols, which are substrates of polyphenol oxidase, was inhibited. This reduction of polyphenol synthesis caused the inhibition of the browning. Cinnamaldehyde treatment repressed the induction of PAL mRNA, while mild heat treatment did not repress its induction. The increase in microbes in cut lettuce treated with cinnamaldehyde was less than that treated with mild heat after 12 days.     

Insect growth regulators with hydrazide moiety inhibit strigolactone biosynthesis in rice

Strigolactones (SLs) are carotenoid-derived plant hormones involved in several growth and developmental processes. Also, SLs are allelochemicals that induce the seed germination of root parasitic plants and the hyphal branching of arbuscular mycorrhizal fungi. In this study, to identify novel lead chemicals that inhibit SL biosynthesis, we evaluated the effect of agrochemicals on SL biosynthesis. We found that the diacylhydrazine insect growth regulator, chromafenozide, reduced the endogenous level of 4-deoxyorobanchol (4DO), a major SL in rice. Furthermore, treatment with the same class of insect growth regulator, methoxyfenozide, also resulted in the reduction of 4DO levels in rice root exudates. These results suggest that chromafenozide and methoxyfenozide are novel lead inhibitors of SL biosynthesis.     

Comparison of right atrium incision and right ventricular outflow incision for surgical repair of membranous ventricular septal defect using cardiopulmonary bypass in dogs

OBJECTIVE: To compare right atrium incision (RAI) and right ventricular outflow incisions (RVI) for surgical repair of membranous ventricular septal defect (VSD) facilitated by cardiopulmonary bypass (CPB). STUDY DESIGN: Retrospective study. ANIMALS: Dogs (n=10) with VSD. METHODS: Medical records of dogs that had VSD repair were reviewed. Membranous VSD without any malformation and abnormality was confirmed on several clinical examinations and by angiocardiography. RAI (5 dogs) and RVI (5 dogs) was used for VSD access and repair facilitated by CPB. Procedure comparison was by surgical duration, postoperative recovery period, and occurrence of postoperative arrhythmia. RESULTS: Duration of surgery was similar for RAI and RVI; however, postoperative recovery time was significantly reduced with RAI. Significant moderate operative damage occurred with right atrium incision. CONCLUSIONS: Right atrium incision was more effective than RVI for repair of membranous VSD using CPB. CLINICAL RELEVANCE: RAI should be considered in preference to RVI for repair of membranous VSD using CPB.     

Predicting of molecules mediating an interaction between bovine embryos and uterine epithelial cells

Embryo-maternal reproductive tract interactions are pivotal for successful pregnancy. The present study predicted the molecules modulating embryo-uterine communication by comparing two sets of differentially expressed genes (DEGs): DEGs in uterine epithelial cells (UECs) collected from the uterus with and without blastocysts and DEGs between blastocysts developed in vivo and in vitro. Cows were subjected to super ovulation (SOV), followed by insemination or non-insemination at estrus (SOV + AI and SOV cows). Seven days after estrus, the uterus was flushed to collect UECs, and the presence of blastocysts in the uterus was confirmed. UECs were subjected to RNA-Sequencing (RNA-Seq) to identify DEGs. Publicly available RNA-Seq data of in vivo and in vitro developed bovine blastocysts were used to determine DEGs. Then, using ingenuity pathway analysis, activated- and inhibited-upstream regulators (USRs) for UECs in blastocysts were compared with those for blastocysts developed in vivo. RNA-Seq of UECs revealed that the DEGs were associated with immune response and cell adhesion pathways. The activated and inhibited USRs of UECs derived from SOV+ AI cows overlapped with the activated and inhibited USRs of blastocysts developed in vivo. Overlapping activated USRs include leukemia inhibitory factor, interleukin 6, fibroblast growth factor-2, transforming growth factor beta-1, and epidermal growth factor. In conclusion, the present study predicted the molecules that potentially mediate communication between the developing embryo and the uterus in vivo and prepare the uterus for pregnancy.