To find novel skin-whitening agents, the melanogenesis inhibitory action of gallic acid (GA) was investigated. In this current study, the effects of GA on mushroom tyrosinase, tyrosinase inhibitory activity, and melanin content were assessed in B16 melanoma cells (B16 cells). Results indicated that GA has a strong antityrosinase activity (IC 50 ‫01؋95.3؍‬ ؊6 M). Furthermore, data on murine tyrosinase activity and melanin biosynthesis revealed that GA effectively suppressed murine tyrosinase action and the amount of melanin. To investigate the relation between GA's inhibition of melanogenesis and antioxidant activity, the effect of GA on reactive species (RS) generation and the reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio in were determined in B16 cells. Results indicated that GA effectively down-regulated the RS generation and enhanced the GSH/GSSG ratio. Based on these results, I propose that GA exerts antimelanogenic activity coupled with antioxidant properties by suppressing RS generation and maintaining a higher GSH/GSSG ratio.

Since the molecular analysis of spike (S) glycoprotein gene of bovine coronavirus (BCoV) has been conducted and compared mainly among American and Canadian isolates and/or strains, it is unclear whether BCoV circulated in the other countries are distinctive in genetic characteristics. In the present study, we analyzed the S glycoprotein gene to characterize 10 winter dysentery (WD) coronavirus strains circulated in Korea during 2002-2003 and compared the nucleotide (nt) and deduced amino acid (aa) sequences with the other known BCoV. The phylogenetic analysis of the entire S glycoprotein gene revealed that the aa sequences of all Korean WD strains were more homologous to each other and were very closely related to respiratory bovine coronavirus (RBCV) strain OK and enteric bovine coronavirus (EBCV) strain LY-138, but were distinct from the other known BCoVs. Based on the phylogenetic analysis of the hypervariable region of the S1 subunit, all Korean WD strains clustered with the respiratory strain OK, BCQ3994 and the enteric strain LY-138, while the Canadian BCQ calf diarrhea and WD strains, and the American RBCV LSU, French EBCV F15 and avirulent VACC, L9, and Mebus strains clustered on a separate major branch. These data suggest that the WD strains circulated in Korea had a genetic property of both RBCV and EBCV and were significantly distinct from the ancestral enteric strain.

Group A rotaviruses are a major cause of acute gastroenteritis in young children as well as many domestic animals. The rotavirus genome is composed of 11 segments of double-stranded RNA and can undergo genetic reassortment during mixed infections, leading to progeny viruses with novel or atypical phenotypes. The aim of this study was to determine if the bovine group A rotavirus strains KJ44 and KJ75, isolated from clinically infected calves, share genetic features with viruses obtained from heterologous species. All 11 genes sequences of the KJ44 and KJ75 strains were sequenced and analyzed. The KJ44 VP4 had 91.7% to 96.3% deduced amino acid identity to the bovine related P[1] strain, whereas the KJ75 strain was most closely related to the bovine related P[5] strain (91.9% to 96.9% amino acid identity). Both KJ44 and KJ75 strains also contained the bovine related VP3 gene. The remaining 9 segments were closely related to porcine group A rotaviruses. The KJ44 and KJ75 strains showed high amino acid identity to the G5 rotaviruses, sharing 90.4% to 99.0% identity. In addition, these strains belonged to the NSP4 genotype B, which is typical of porcine rotaviruses and subgroup I, with the closest relationship to the porcine JL-94 strain. These results strongly suggest that bovine rotavirus strains with the G5 genotype occur in nature as a novel G genotype in cattle as a result of a natural reassortment between bovine and porcine strains.Group A rotaviruses are a major cause of acute gastroenteritis in young children and in a wide variety of domestic animals (5, 22, 63). These viruses, belonging to the Reoviridae family, are nonenveloped, icosahedral particles consisting of 11 segments of double-stranded RNA (dsRNA) enclosed in a triple-layered protein capsid (8). The two outer capsid proteins, VP7 and VP4, independently elicit neutralizing antibodies, which induce protective immunity and are used to classify the rotavirus strains into G (for glycoprotein) and P (for protease sensitive) sero-or genotypes (8). The inner capsid protein, VP6, bears subgroup (SG) specificities that allow the classification of group A rotaviruses into SGI, SGII, both SGI and SGII, or neither SG based on reactivity with the SGspecific monoclonal antibodies (8).The serotypic and genotypic characterization of rotavirus strains is important for determining the extent of the diversity in circulating strains. In extensive serological and genomic studies, 15 G serotypes and 26 P genotypes have been established for rotaviruses of humans and animals thus far (17,27,39,40,42,44,52,53). The most common rotavirus G serotypes found in humans are G1, G2, G3, and G9. Although it was originally believed that animal rotaviruses did not infect humans under natural conditions (34), the intensification of rotavirus surveillance, together with the development of better characterization methods for typing previously nontypeable strains, has resulted in the detection of animal-like rotavirus strains such as porcine-like G5 and bovine-like G6, G8, and G10 in huma...

ABSTRACT. Although winter dysentery (WD) has been suspected to occur frequently in Korea, to date the exact epidemiology of WD has remained unknown. Therefore, we investigated the causative agents of WD by using electron microscopy, ELISA, RT-PCR, and nested PCR from 97 fecal samples of 32 WD-affected herds collected from 8 provinces during [2002][2003][2004]. The bovine coronavirus (BoCV) was consistently detected in all herds with WD. Of other pathogens, only coccidian oocyts were inconsistently but concurrently detected with BoCV. Ten isolates were identified as BoCV by immune electron microscope, immunofluorescent test and ELISA with antiserum to BoCV, and RT-PCR. From these results, it is concluded that WD caused by BoCV occurred in relatively high frequency and was widespread in Korea. The results provide important epidemiological data for the control and establishment of a surveillance system for WD in Korea. KEY WORDS: bovine coronavirus, Korea, winter dysentery prevalence.

Abstract. Segmental aplasia of the uterine body was diagnosed in a 5-year-old, mixed breed bitch. Abdominal radiography and transabdominal ultrasonography revealed marked dilation of fluid-filled uterine horns with no evidence of a uterine body. Sex hormone assays did not detect the presence of estradiol-17 ␤; however, progesterone (2 ng/ml) was found in the serum, indicating anestrus. On gross examination of the reproductive tract, the uterine body was absent, apparently never formed. In its place, a cord-like piece of tissue was identified as an aplastic/dysplastic remnant, connecting the cervix and right uterine horn. The tip of the cord-like piece branched into 5 string-like pieces of tissue, 1 of which was connected to the region dividing the left and right uterine horns. Both the uterine horns were dilated markedly revealing hydrometra. Histologically, uterine body remnant tissues from the endometrium, myometrium, and perimetrium were detected in proximal and distal parts of the uterine body. The string-like piece of tissue connecting the uterine body remnant and the uterine horn consisted of a round cluster of smooth muscle cells surrounding a central core of adipose tissue with blood vessels. It was concluded that the hydrometra observed in both uterine horns was induced by an obstruction resulting from segmental aplasia in the uterine body. This is the first known report of segmental aplasia in the uterine body of a bitch.