Journal of Veterinary Medical Science最新文献

Mononuclear cell infiltration of the central nervous system and ganglioneuritis are characteristic histopathological findings of proventricular dilatation disease (PDD) caused by parrot bornavirus (PaBV) infection. The purpose of this study was to clarify the link between the degree of inflammatory lesions and the distribution of the virus antigen in naturally PaBV-infected parrots. Pathological examination was performed on 18 PaBV-infected birds identified by reverse transcriptase-PCR. Dilatation of the crop, proventriculus, and ventriculus was observed in all 18 (100%) birds, and dilation of the right ventricle of the heart was observed in 14/18 (78%) birds. Cases were classified based on the scores for the distribution and degree of histological lesions into neural type, with severe brain lesions, digestive type, with severe gastric lesions, or nervous/digestive type, with severe lesions in both the brain and ventriculus. The PaBV immunohistological score correlated with the inflammatory lesion scores. Ganglioneuritis, myocarditis, and myocardial degeneration were frequently observed in the heart. Interestingly, macroscopic and microscopic lesions and virus antigen were detected in the hearts of all three histological types. The present study showed that parrots naturally infected with PaBVs can be grouped into three types based on the lesion distribution, and heart failure is an important symptom in PaBV-infected parrots.

This study describes a novel surgical method to remove urinary bladder-related urachal abscesses in a cow. Traditional methods, such as the midline or paramedian approach in calves and the preinguinal approach, can be challenging in adult cattle, especially for lesions situated near the pelvic cavity. In this case, a 4-year-old cow had a urachal abscess attached to the bladder apex, making it difficult to approach via abdominal wall incision. Colpotomy and pulling the abscess through a vaginal wall incision allowed for complete exteriorization of the lesion and comfortable accessibility of the abscess and the resection site. This report suggests that colpotomy is an effective new route in adult cattle for accessing urachal abscesses not accessible via traditional surgical approaches.

Myristoylated alanine-rich protein kinase C substrate (MARCKS) plays crucial roles in neuronal functions and differentiation. However, specific effects of the myristoylated N-terminal sequence (MANS) peptide, a widely used MARCKS modulator comprising the initial 24 amino acids of MARCKS, on neuronal cells remain unclear. Therefore, in this study, we aimed to examine the effects and action mechanisms of the MANS peptide on SH-SY5Y human neuroblastoma cells, which served as the in vitro neuronal cell models. MANS treatment of SH-SY5Y cells resulted in significant neurite outgrowth within 24 hr, which was as prominent as that induced by seven days of treatment with all-trans retinoic acid, the most common agent used to induce SH-SY5Y cell differentiation. Levels of synaptophysin, a neuronal marker protein, were significantly increased in the MANS peptide-treated cells. Additionally, increased MARCKS levels and decreased MARCKS phosphorylation were observed in MANS peptide-treated cells. Notably, neurite outgrowth induced by the MANS peptide was significantly reduced in MARCKS-knocked-down cells. Overall, these results suggest the MANS peptide as a novel agent for SH-SY5Y cell differentiation, particularly for the analysis of MARCKS functions.

Endotoxemia is a systemic inflammatory condition caused by lipopolysaccharide (LPS) stimulation, which produces inflammatory cytokines. Fuzapladib (FZP) inhibits the activation of adhesion molecules found on the surface of inflammatory cells, mitigating inflammation. In this study, we evaluated the therapeutic effects of fuzapladib on inflammatory cytokines and cardio-respiratory function using an LPS-induced endotoxemic porcine model. Fifteen pigs were separated into three groups: low-FZP (n=5), high-FZP (n=5), and control (n=5). Pigs were administered LPS under general anesthesia, and complete blood cell count, blood biochemistry, inflammatory cytokines, and cardio-respiratory function were evaluated. Statistical analysis was performed using a linear mixed-effects model and the Steel-Dwass test, with a significance threshold of P<0.05. During the 4 hr experimental period, one pig in the control group and two pigs in the low-FZP group died due to hypoxemia and hypotension. In the early acute changes following LPS administration, the high-FZP group maintained significantly higher arterial oxygen partial pressure and normal blood pressure compared to the control group. Although interleukin-6 levels increased in all groups during the experiment, they were significantly lower in the high-FZP group compared to the control group. Other parameters showed no clinically significant differences. In conclusion, while high-dose fuzapladib did not reduce organ damage in the porcine endotoxemia model, it suppressed interleukin-6 production, delayed the progression of deterioration, and contributed to a reduction in mortality during the observation period.

Cell-free DNA (cfDNA), the DNA in the blood circulation, is a useful marker for diagnosing hereditary diseases and tumors. However, the mechanisms underlying the generation of cfDNA are not completely understood. We previously studied DNases [Caspase-activated DNase (CAD), DNase1L3, and DNase I] and reported that in acetaminophen-induced liver necrosis, DNase1L3 was the main endonuclease generating cfDNA, with CAD playing a supporting role. In this study, we generated triple-gene knockout (TKO) mice, Cad^-/-DNase1L3^-/-DNase1^-/-, and found that DNase I also contributed to cfDNA generation. Given that a defect in DNase1L3 or DNase I is involved in autoimmune diseases, TKO mice would be useful as a disease model and tool for identifying the in vivo roles of endonucleases.

Campylobacter fetus is a zoonotic pathogen. Although the precise virulence mechanisms have not yet been fully elucidated, cytolethal distending toxin (CDT) is considered as one of the well-characterized virulence factors in Campylobacter. In silico analysis of the genome of C. fetus type strain of ATCC27374^T indicates that there are three cdt gene clusters, Cfcdt-I, Cfcdt-II and Cfcdt-III. However, it is not clear whether these clusters are ubiquitously present in C. fetus and their association with diseases in humans and animals. In this study, we have analyzed the distribution and nucleotide sequences of these cdt gene clusters in 137 C. fetus strains isolated from human patients and healthy cattle. MLST and PFGE were also applied to determine clonal relationship between C. fetus strains isolated from patients and cattle. We found all C. fetus strains carry three Cfcdt gene clusters by colony hybridization assay and the strains belonged to 38 different pulsotypes. Whole genome sequencing of 38 C. fetus strains was carried out to determine the entire cdt gene cluster sequences and their sequence type (ST). Among 38 strains, six STs were identified, and each cdt gene cluster showed high similarity (>99%). Interestingly, some of these Cfcdt genes are more similar to the cdt genes of other Campylobacter species than other Cfcdt gene types. Altogether, the results suggest that three Cfcdt gene clusters are highly conserved in C. fetus and the strains belonging to ST-6 may be more pathogenic to human.

The aim of this pragmatic approach to retrospective observational study was to identify the end-tidal concentration of sevoflurane which was associated with optimal surgical conditions (i.e., absence of any movement, coughing and straining) in 127 pregnant sheep. Optimal surgical conditions were observed in 90% of the ewes with an end-tidal concentration of sevoflurane of 2.4 Vol-% [95% CI: 2.2; 2.8] during minimal-mild nociceptive stimuli (placement of arterial catheter, bladder catheter, shaving), with 4.4 Vol-% [95% CI: 4.0; 5.2] during maternal laparotomy and hysterotomy and with 4.4 Vol-% [95% CI: 3.9; 5.8] during subsequent manipulation of the uterus and fetal surgery.

Herein, we investigated the positional relationship between the cervical esophagus and trachea using computed tomography (CT) images in dogs with tracheal flattening. From these CT images, the ratio of the tracheal diameters in the short (vertical) and long (horizontal) axes of the tracheal ring (S/L ratio) and the vertebra - trachea - esophagus (VTE) angle were measured at the point from the 3rd cervical (C3) to the 3rd thoracic vertebra (T3) levels. The VTE angle in dogs with tracheal flattening with an S/L ratio under 0.24 tended to be smaller than the angles at the level from C4 to T2 in dogs with an S/L ratio over 0.25. The positional relationship between the esophagus and trachea seems to be possibly related to tracheal cross-sectional shape.

Allergic dermatitis (AD) is a skin disease characterized by a chronic inflammation caused by immune dysregulation. In the histopathology of patients with AD, there are several features, such as accumulation of eosinophils and mast cells, hyperkeratosis, and dermal fibrosis which are related to the exacerbation of AD. Mast cells and eosinophils are thought to be involved in fibrosis, but the details are unknown. Yama mouse is an inbred mouse showing genetically eosinophilia. If eosinophils have significant effect on fibrosis, it may be possible to establish a new AD model with severe fibrosis. In this study, AD was induced by applying dinitrofluorobenzene to mice auricle. Yama mice showed AD lesion with more severe dermal fibrosis with severe eosinophil infiltration than Balb/c and Nc/nga mice. The expression of transforming growth factor-β (TGF-β), a cytokine important for fibrosis, was not significantly different among Yama, Balb/c, and Nc/nga mice, while the expression of interleukin-4 (IL-4), which is also mediator of tissue fibrosis, was increased only in Yama mice. The results of this study showed that AD with more severe fibrosis could be induced in Yama mice than in Balb/c and Nc/nga mice. In Yama mice, it can be concluded that the severe fibrosis is TGF-β independent, and IL-4 would be the main mediator of severe fibrosis. This mouse model may be useful for elucidating the mechanism of fibrosis in chronic AD, and for conducting research leading to the development of new therapies.

An 8-year-old castrated male mixed-breed cat presented with an abdominal mass of unknown origin, accompanied by eosinophilia. Autopsy revealed mild-to-severe enlargement of lymph nodes throughout the body and multiple nodules in the lungs. Histopathologically, the lymph nodes showed severe fibroplasia and infiltration by a large number of eosinophils and fewer tumor cells, exhibiting large-sized lymphoid cell morphology. Metastatic lesions of tumor cells with eosinophilic infiltration and fibrosis were observed in the lungs, liver, kidneys, stomach, and intestines. Immunohistochemistry revealed that the tumor cells were positive for CD3 and negative for B cell and mast cell markers. Thus, T-cell lymphoma with eosinophilic infiltration and sclerosing fibroplasia was diagnosed.