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The red-eared sliders (Emydidae: Trachemys scripta) is characterised by a high adaptability to a variety of environment and threatens the habitat of Japanese native species. The ability to digest a variety of diets may attribute to the high adaptive capacity of this species to various environments, however, the digestive morphology remains scarcely described in red-eared sliders. In this study, we investigated the macro- and microscopic anatomy of the esophagus, stomach, small intestine, and large intestine in red-eared sliders. All segments of the digestive tract had longitudinal mucosal folds, the height and width of which varied in each segment of the digestive tract. The stomach had the highest and widest mucosal folds. The mucosal folds in the proximal-to-middle small intestine exhibited a zigzag shape, whereas those in the distal small intestine were linear. The wall of the digestive tract regularly consisted of mucosa, submucosa, tunica muscularis, and tunica adventitia or serosa. In each segment of the digestive tract, the epithelial structure was different. The esophagus and small intestine were lined by the pseudostratified columnar epithelium. In both segments, the basal part of the pseudostratified epithelium included proliferating cell nuclear antigen (PCNA)-positive proliferating cells. The stomach and large intestine were lined by the simple columnar epithelium. In the stomach and large intestine, PCNA-positive proliferating cells were present in the neck of the proper gastric gland and crypt-like structures, respectively. The proper gastric gland was composed of oxynticopeptic and mucous cells. This study revealed the detailed macro- and microscopic anatomy of the digestive tract in red-eared sliders. Overall, our findings may provide an anatomical basis for understanding the relationship between morphology and function in the digestive tract of turtles. [ABSTRACT FROM AUTHOR]

Simple Summary: Toxicologists know that peroxisome proliferator-activated receptors α agonists can induce peroxisomal proliferation in the liver of rodents but do not know whether pexophagy follows peroxisome proliferation. We showed that clofibrate, a peroxisome proliferator-activated receptors α agonist, induced pexophagy in the high-fat diet-fed rats through the pexophagy regulators. These novel findings suggested that rodent peroxisome proliferation with peroxisome proliferator-activated receptors α agonists is useful for understanding the biology of pexophagy in mammals and impacts the research on selected autophagy. Peroxisomes are crucial for fatty acid β-oxidation in steatosis, but the role of pexophagy—the selective autophagy of peroxisomes—remains unclear. This study investigated the effects of the peroxisome proliferator-activated receptor-α (PPARα) agonist clofibrate on pexophagy in a coconut oil-based high-fat diet (HFD)-induced hepatocarcinogenesis model. Rats were divided into four groups: control, clofibrate, HFD, and HFD with clofibrate. The HFD induced steatosis, along with a 2.4-fold increase in pexophagy receptor NBR1-positive granules in hepatocytes. Clofibrate significantly inhibited HFD-induced steatosis, increasing p62-, LAMP2-, and Pex5-positive granules by 7.5-, 7.2-, and 71.4-fold, respectively, while decreasing NBR1 expression. The effects were associated with peroxisome proliferation and pexophagy in ultrastructural observations and increased levels of Lc3, p62, Pex2, Pex14, Acox1, and Scd1 in gene expression analysis. The results suggested that clofibrate effectively reduced steatosis through combined peroxisome proliferation and pexophagy, though it had a marginal impact on hepatocarcinogenesis in coconut oil-based HFD-fed rats. These findings highlight the utility of PPARα agonists in studying mammalian pexophagy. [ABSTRACT FROM AUTHOR]

Although hyperplasia of the anorectal transitional zone (TZ) has been reported in mouse models of ulcerative colitis, the mechanisms underlying this phenomenon are not fully understood. We characterized keratin subtypes and examined the expression of stem cell markers in the TZ. Dextran sodium sulfate-treated mice showed abnormal repair of the anorectal region, which consisted of mixed hyperplastic TZ and regenerating crypts. Liquid chromatography-tandem mass spectrometry from the paraffin-embedded TZ in the treated mice revealed that the major keratins were type I cytokeratin (CK)13 and type II CK5, but notable expression of type I CK10 and CK42 and type II CK1, CK4, CK6a, CK8, and CK15 was also detected. Hyperplastic TZ was characterized by the expression of tumor protein 63, sex-determining region Y-box 2 (SOX2), SOX9, and leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5). Lgr5 was highly expressed in the TZ in the early stages of colitis, followed by higher expression levels of SOX2. The TZ-derived organoids expressed LGR5, SOX2, and SOX9. The present study suggests that transitional zones showing abnormal keratin assembly and stem cell activation may interfere with rectal crypt regeneration, leading to pathological anorectal remodeling in severe colitis. [ABSTRACT FROM AUTHOR]

Variations in the pattern of urogenital vessels can arise as a single occurrence or as a combination, which may increase the risk of unexpected injury during surgical procedures. Multiple variations in the renal and testicular vessels, in a novel combination, were observed during the dissection of an 87-year-old Japanese male cadaver. In the present case, the patient had 2 renal arteries on each side. On the right side, the superior and inferior renal arteries emerged from the abdominal aorta at the L1 and L4 vertebrae levels, respectively. On the left side, the superior renal artery originated from the abdominal aorta at the level of the L1/L2 intervertebral disc, whereas the inferior renal artery arose at L4. The right testicular artery emerged from the abdominal aorta at the level of the L2 vertebra and crossed the inferior vena cava posteriorly. The venous system also exhibited some variations. The left renal vein passed posteriorly to the abdominal aorta and opened into the inferior vena cava at the level of the L2 vertebra. On the course to the inferior vena cava, the left renal vein was connected only to the first lumbar, azygos, and hemiazygos veins; blood was not collected from the left testicular and suprarenal veins, which usually open into the left renal vein. The patient had 2 right testicular veins. The lateral one opened into the angle between the right renal vein and the inferior vena cava at the level of the L2 vertebra, and the medial one drained into the inferior vena cava at a level slightly lower than the lateral one. Knowledge of the possible anatomical variations may be beneficial for performing safe retroperitoneal surgery and understanding the development of these vessels. [ABSTRACT FROM AUTHOR]

Rabbit large intestine has a segment‐specific morphology and motility. However, the morphological features of the myenteric plexus, which controls intestinal motility, have not been characterized in each large intestinal segment. We investigated the myenteric plexus morphology in the rabbit large intestine using protein gene product 9.5 immunohistochemistry in whole‐mount preparations. The tenial part of the first and second segments of the proximal colon had the most well developed myenteric plexus, while the caecum had the least. These findings suggest different neuronal control over the motility of each intestinal segment, thereby providing a fundamental understanding of the rabbit enteric nervous system. [ABSTRACT FROM AUTHOR]

Intestinal surgery is commonly performed to cure bowel obstruction in rabbits, but detailed descriptions of the arterial supply to the intestine are incomplete. We investigated anatomical variations of the distribution of the cranial mesenteric artery to the intestine in 33 New Zealand White rabbits by injecting colored latex into the arteries. The cranial mesenteric artery arose independently from the abdominal aorta at about 2.0 cm caudal to the celiac artery and branched off the pancreaticoduodenal, middle colic, ileocecocolic, jejunal and ileal arteries. One or occasionally two caudal pancreaticoduodenal arteries supplied the distal duodenum, and one to three middle colic arteries supplied the transverse colon and the initial portion of the descending colon. The ileocecocolic artery arose distal to the middle colic arteries and provided the right colic, ileocecal and appendicular arteries, and branches to the proximal colon, with various branching patterns, which were grouped into four major types. These arteries and branches supplied the ileum, cecum, appendix and proximal colon. The cranial mesenteric artery also provided the jejunal arteries (predominantly 17; range 11–21) and one ileal artery supplying the jejunum and proximal ileum, respectively. The results show that the distribution patterns of the cranial mesenteric artery to the intestine in the rabbit are highly specialized to this species. Such specialization should always be considered when performing intestinal surgery in rabbits. [ABSTRACT FROM AUTHOR]

We demonstrate an aberrant ramification pattern of the renal and testicular vessels. On both sides, the anterior and posterior renal veins emerged from the renal. On the right side, the anterior renal vein collected the right testicular vein and drained into the inferior vena cava, while the posterior one directly drained into the inferior vena cava. Two retrocaval testicular arteries originated from the aorta. On the left side, the perinephric vein drained from the abdominal wall and adrenal gland and joined the anterior renal vein. The anterior renal vein also collected the testicular, suprarenal, and inferior phrenic veins. The posterior one received the other testicular vein and the first three lumbar veins. These renal veins converged, passed anteriorly to the aorta, and drained into the inferior vena cava. Knowledge of the varied anatomy of these vessels will contribute to safe surgical approach to the kidneys.

The common marmoset (Callithrix jacchus) has attracted much attention as a nonhuman primate animal model for stress-related experiments. The adrenal gland plays a key role in stress responses and has abundant vasculature, through which the hypothalamic-pituitary axis hormonally controls its activity. Understanding the arterial supply pattern to the gland is fundamental to understanding its function and performing experiments. We therefore traced the arteries supplying the adrenal gland in six male and nine female common marmosets using the latex injection method. The adrenal artery originates from one to four parent arteries, including the caudal phrenic, celiac, left gastric, gonadal, and renal arteries and the abdominal aorta. The branching pattern of the adrenal arteries was divided into Types 1 to 4, having 1-4 parent arteries, respectively. Type 2 was most frequent on the right side (seven of 15 halves, 46%), whereas Type 3 was most frequent on the left (eight of 15 halves, 53%). The number of cranial, middle, and caudal adrenal arteries ranged from one to four in the cranial, one to five in the middle, and one to six in the caudal adrenal arteries. The total number of adrenal arteries varied from three to 13, predominantly as five on one side. The present study revealed frequent individual variations in the origin and number of adrenal arteries in the common marmoset, which may be informative for further research involving the adrenal glands in this species.

Sarcocystis spp. cause pigeon protozoan encephalitis, a neuronal disease. A female pigeon exhibiting torticollis had a necrotic area in the cerebral hemisphere surrounded by lesions with perivascular cuffing, gliosis, granulomatous foci, and meningitis. Non-necrotic lesions were also observed in the brainstem. Intact and degenerative schizonts were observed within the neuropils and neurons in the lesions. Deoxyribonucleic acid (DNA) was extracted from paraffin-embedded brain tissues and genetically analyzed after gel electrophoresis to determine Sarcocystis spp. using specific primer sets for 28S ribosomal ribonucleic acid and internal transcribed spacer region-1. DNA sequencing confirmed a significant homology with S. calchasi. This is the first report of meningoencephalitis with malacia caused by S. calchasi in a rock pigeon in Japan.

N-methyl-N-nitrosourea (MNU) exposure impairs hippocampal neurogenesis in rats. The present study investigated the gene expression profiles that were commonly up or downregulated across different brain substructures in response to repeated MNU administration in rats. Five-week-old rats were orally administered MNU at 0, 5, 15 mg/kg body weight/day for 28 days and subjected to gene expression microarray analysis in the hippocampal dentate gyrus, corpus callosum, cerebral cortex and cerebellar vermis. MNU at 15 mg/kg revealed multiple functional clusters of upregulated genes related to immune and inflammatory responses in all brain regions, and also clusters of up or downregulated genes related to regulation of apoptotic process in several regions. Specifically, the upregulated genes commonly found in all four regions were enriched in clusters of "immune response" and/or "inflammatory response" (Cd74, Ccl3, Fcgr3a, Serping1, Lgals3, Fcgr2b, Hcst, Kcnn4, Tnf, Gpr18, Tyrobp and Cyba) and "metal-binding proteins" (Mt1, Mt2A and Apobec1). Meanwhile, downregulated genes common to all four regions (Bmp4, Vcan and Fhit) were included in clusters of "cell proliferation", "glial cell migration" and "nucleotide metabolism". Immunohistochemical analysis of representative gene products revealed that in all brain regions examined, MNU treatment increased metallothionein-I/II + cells and galectin-3 + cells co-expressing Iba1, and also increased Iba1 + and CD68 + cells. These results suggest that repeated MNU administration in rats causes neuroinflammation and oxidative stress accompanied by apoptosis of neural cell components in the brain, as well as concurrent anti-inflammatory responses for neuroprotection from MNU exposure, involving activation of microglia producing metallothionein-I/II and galectin-3 on these responses.

Uterine adenocarcinoma occurs in more than 60% of female rabbits aged 4 years and over. To cure or prevent this uterine disorder, ovariohysterectomy should be performed. Although knowledge of the arterial supply to the ovary, uterus, and vagina is required, few studies have described the arterial anatomy. Therefore, we dissected ovarian, uterine, and vaginal arteries in 15 New Zealand White and 15 Japanese White rabbits to clarify the anatomy. The ovarian artery arose from the abdominal aorta, and in 50% of cases, the left artery emerged more cranially than the right artery. The ovarian artery provided the ovarian, uterine, and tubal branches with three branching types. The most frequent type (67% of the halves on the right and 63% of the halves on the left) exhibited three branches that independently arose from the ovarian artery. The uterine artery usually originated from the umbilical artery, with its ramification pattern divided into two types, having one or two uterine arteries, respectively. The most frequent type (all halves on the right and 83% of the halves on the left) had one uterine artery that originated from the umbilical artery. We observed three types of vaginal artery origins, with the branching type where the vaginal artery arose from the internal iliac artery being the most frequent (97% of the halves on the right and 90% of the halves on the left). The detailed arterial supply pattern of the rabbit female genital organs determined in the present study will be helpful when performing rabbit gynecological surgeries. Anat Rec, 303:1478-1488, 2020. © 2019 American Association for Anatomy., (© 2019 American Association for Anatomy.)