Positive correlation between renal tubular flattening and renal tubular injury/interstitial fibrosis in murine kidney disease models

The number of patients with chronic kidney disease (CKD) is growing continuously globally. In order to study pathogenesis and mechanisms, many animal models have been developed, including spontaneous, genetic, and induced models. Although each type of CKD shows disease-specific tissue changes in the early stages, tubular disorder and interstitial fibrosis histologically occur in the course of progression to end-stage renal failure. Therefore, the quantification of tubular disorder and interstitial fibrosis in CKD research using animal models is essential for measuring the degree of CKD severity and, thus, efficacy of therapeutic agents. Several strategies have been used to quantify interstitial fibrosis. Among scoring factors, renal tubular flattening can be quantitatively evaluated easily and inexpensively. However, the diagnostic value of renal tubular flattening evaluation has not been investigated previously. Therefore, in this study, we investigated the correlation between renal tubular flattening and interstitial fibrosis or renal tubular injury markers. We observed a strong correlation between the degree of tubular injury/interstitial fibrosis and renal tubular flattening in three types of mouse renal disease model. This is advantageous because rapidly advancing technologies such as artificial intelligence and image processing can be easily applied; hence, a more precise, objective, and quantitative diagnosis should be possible in the future.     

Survey of tortoises with urolithiasis in Japan

Urolithiasis is a disease often seen in tortoises at veterinary hospitals, however there have been no comprehensive research reports of tortoises with urolithiasis in Japan. In this study, we analyzed tortoises diagnosed with urolithiasis at three domestic veterinary hospitals. Based on medical records, we assessed the diagnostic method, species, sex, body weight, dietary history, husbandry, clinical signs, clinical examination, treatment for urolithiasis, and clinical outcome. The total number of cases in the 3 facilities was 101. As for species of tortoises, the most common was the African spurred tortoise (Centrochelys sulcata) with 42 cases (41.6%), followed by the Indian star tortoise (Geochelone elegans) with 30 cases (29.7%). Six other species were confirmed to have calculi. Almost all cases (99 cases, 98%) had a single calculus, and only 2 had multiple calculi. The prevalence of urolithiasis for the total number of tortoises having visited to one institution during the same period was 5.1%. Of the 86 cases that underwent calculi removal, 64 (74.4%) were successfully removed via the vent, and the efficacy of this method was confirmed. Nineteen cases (22%) were approached via plastronotomy, among which only 2 died postoperatively. In this study, we could not clarify the relationship between calculi formation and diets or other husbandry factors.     

Oocyte-specific gene knockdown by intronic artificial microRNAs driven by Zp3 transcription in mice

Conditional knockout technology is a powerful tool for investigating the spatiotemporal functions of target genes. However, generation of conditional knockout mice involves complicated breeding programs and considerable time. A recent study has shown that artificially designed microRNAs (amiRNAs), inserted into an intron of the constitutively expressed gene, induce knockdown of the targeted gene in mice, thus creating a simpler method to analyze the functions of target genes in oocytes. Here, to establish an oocyte-specific knockdown system, amiRNA sequences against enhanced green fluorescent protein (EGFP) were knocked into the intronic sites of the Zp3 gene. Knock-in mice were then bred with EGFP transgenic mice. Our results showed that Zp3-derived amiRNA successfully reduced EGFP fluorescence in the oocytes in a size-dependent manner. Importantly, knockdown of EGFP did not occur in somatic cells. Thus, we present our knockdown system as a tool for screening gene functions in mouse oocytes.     

Effect of the liquid form of traditional Chinese medicine,Hozen-S,on gastric motility in dogs

Juzen-taiho-to, a traditional Chinese herbal medicine, is used for patients with anorexia and fatigue in human medicine. In our previous study, granulated Juzen-taiho-to improved vincristine-induced gastrointestinal adverse effects through increasing gastric motility in dogs. As the effect of Hozen-S, the sweet liquid form of Juzen-taiho-to, on dog gastric motility has not been investigated, we examined the effect of administration of Hozen-S on gastric motility. Furthermore, we assessed dog plasma ghrelin level to further elucidate the mechanism of the effect of Hozen-S on gastric contraction. Finally, we assessed the palatability of Hozen-S compared to granulated Juzen-taiho-to and its effect on body weight in dogs. Administration of Hozen-S significantly increased gastric motility, plasma ghrelin concentration, and body weight. A palatability evaluation revealed that the dogs preferred Hozen-S to granulated Juzen-taiho-to. In conclusion, Hozen-S administration to dogs promoted gastric motility by raising plasma ghrelin levels. Considering these functional and palatability data, Hozen-S may replace granulated type Juzen-taiho-to and become a prominent traditional Chinese veterinary medicament.     

Characterization of Campylobacter jejuni in large-billed crows (Corvus macrorhynchos) in Tochigi prefecture,Japan

As free-living crows are a potential source of Campylobacter infections in broilers and cattle, we characterized Campylobacter spp. isolated from crows using multilocus sequence typing and antimicrobial susceptibility testing. We obtained 82 samples from 27 birds captured at seven different times using a trap set in Tochigi prefecture, Japan. Campylobacter jejuni was isolated from 55 (67.1%) of the 82 samples and classified into 29 sequence types, of which 21 were novel. Tetracycline and streptomycin resistance rates were 18.2% and 3.6%, respectively. These results show that most types of C. jejuni infecting crows differ from those isolated from humans, broilers, and cattle. Thus, the importance of free-living crows as reservoirs of Campylobacter infections in broilers and cattle may be limited.