不同毒力水貂阿留申病毒在猫肾细胞中的增殖特性及凋亡特性的比较研究

试验旨在对不同毒力水貂阿留申病毒（Aleutian mink disease virus,AMDV）在猫肾细胞（feline kidney cell,CRFK）中的增殖规律及其诱导细胞凋亡情况进行比较研究。将标准毒株AMDV-G及分离到的野毒株AMDV-DL124、AMDV-DL125、AMDV-QD2、AMDV-QD3、AMDV-ZJ3接种CRFK细胞,应用间接免疫荧光、实时荧光定量PCR、TCID₅₀测定技术研究病毒在细胞中的复制及表达情况,同时检测病毒诱导的细胞凋亡情况。间接免疫荧光结果显示,5株野毒株荧光着色趋势差异不大,均在感染后12 h出现荧光,随感染时间延长荧光增多,AMDV-G荧光出现时间比野毒株晚,但病毒感染后72 h几乎所有细胞均出现荧光;实时荧光定量PCR结果显示,基因组复制趋势大致相同,AMDV-DL125感染后3 h复制开始,AMDV-G感染后24 h复制才开始并呈快速增长趋势,但感染后72 h均达到峰值。TCID₅₀检测结果表明,0~12 h为病毒感染潜伏期,AMDV-G感染后60 h达到峰值,野毒株均在感染后72 h达到峰值,但是6株病毒均能在感染后48~72 h维持较高的感染滴度,其后随细胞崩解而降低。SPSS 23.0统计软件分析凋亡检测结果显示,与对照组相比,野毒株感染细胞后2~12 h诱导细胞凋亡差异显著（P<0.05）,AMDV-G诱导细胞凋亡差异明显低于野毒株,但是诱导细胞凋亡时间较野毒株长,在感染后24 h仍对细胞凋亡有较明显的诱导作用,但是各病毒诱导的细胞凋亡主要集中在2~12 h。该结果为AMDV的培养、鉴定及致病机理研究提供一定参考。     

The ultrasonographic appearance of renal medullary striations and their association with renal disease and renal histopathology in domestic cats

Medullary striations (MS) have been anecdotally observed on ultrasound of feline kidneys; however, their significance is unknown. Aims of this retrospective, case control, pilot study were to describe the appearance, prevalence, and clinicopathological correlates of MS in a referral feline population. Still images from 1247 feline abdominal ultrasound studies performed between 2011 and 2021 were reviewed. Cats with MS were identified and compared with age-matched controls. Serum urea, creatinine, calcium, phosphate, and calcium-phosphate-product, plus urine specific gravity, urine protein: creatinine ratio (UPC), prevalence of active sediment (defined as > 5 red (RBC) or white blood cells (WBC) per high-power field) and prevalence of positive urine culture were compared between MS and control groups using the Mann–Whitney U test or Fisher's Exact test. Data are presented as median [range]. 27 cats were identified as having MS, giving a prevalence of 2.2% with a significantly higher proportion being seen in males (P = 0.018). Medullary striation cats had significantly higher UPC values than controls (0.46 [0.16–7.57] vs. 0.16 [0.07–2.27]; P = 0.006). Cats with MS were more likely to have active urinary sediments (39% vs 8%, P = 0.023), but no difference in prevalence of positive urinary cultures was observed between groups. There was no significant difference in other parameters between MS and control cats. Renal histopathology performed in three MS cats revealed focal regions of linear medullary fibrosis. Medullary striations are associated with proteinuria and urinary tract inflammation in cats, which may reflect renal tubular dysfunction and/or inflammation. Hence identification might allow for earlier detection of renal pathology.     

Morphological analyses of nephrin expression in progressive glomerulonephropathy of common marmosets

In this study, we focused on nephrin, one of the key molecules within the slit diaphragm of podocytes, as although there have been reports on its expression in humans and rats, their presence in common marmosets has not been reported. We investigated nephrin expression and changes in glomeruli, depending on the development of spontaneous progressive glomerulonephropathy in common marmosets. Nineteen common marmosets at two to ten years of age were evaluated. The kidney was examined by microscopy with hematoxylin and eosin and immunohistochemical staining for nephrin. The lesions were classified into three grades according to a renal lesion grading system reported previously. The nephrin-positive area was measured by morphometric analysis, and the nephrin-positive ratio was calculated. Nephrin expression was observed along the glomerular capillary loop in a continuous linear pattern in renal lesion grades 0 to 2 and either discontinuous linear or coarse granular pattern in grade 3. Nephrin expression tended to decrease significantly depending on the grade of renal lesions. Alteration in nephrin expression has been suggested to play an important role in the progression of renal lesions.     

Spontaneous Renal Tumors Suspected of Being Familial in Sprague-Dawley Rats

Spontaneous renal tubule tumors (RTTs), with a distinctive morphological phenotype, were present in three Sprague-Dawley rats, 1 male and 2 females, out a total of 120 animals of each sex from untreated and placebo control groups in a 2-year carcinogenicity study. One female had one carcinoma, adenoma and hyperplasia, and the other female had five adenomas and many hyperplastic lesions; the male case had one carcinoma. From these cases, a biological continuum of hyperplasia, adenoma and carcinoma could be recognized. The tumors were present in the renal cortex and appeared as solid lobulated growths with occasional central necrosis. The lobules were divided by a small amount of fibrovascular tissue. Occasionally the larger tumors contained a cystic area. Tumor cells appeared distinctive and exhibited variable amounts of eosinophilic/amphophilic and vacuolated cytoplasm. Nuclei were round to oval with a prominent nucleolus. Mitotic figures were uncommon, and no distant metastasis was noted. The tumors were seen as multiple and bilateral lesions in two animals and had no apparent relationship to chronic progressive nephropathy (CPN). Foci of tubule hyperplasia were also noted to contain the same type of cellular morphology. The morphological and biological features of these 3 cases resembled the amphophilic-vacuolar (AV) variant of RTT that has been posited to be of familial origin. This is a report of spontaneous familial renal tumors in Sprague-Dawley rats from Japan.     

棉酚对雄性小鼠增重及肾脏组织的影响

选择体质量为（24．69±1．01）g的雄性昆明小鼠90只,随机分为5组。对照组为不含棉酚的全价饲料组,试验组日粮中添加不同质量浓度的提取棉酚,试验I～Ⅳ组添加量分别为每天40、80、120、160mg／kg。结果显示,试验6周结束后,试验小鼠体质量随日龄增加而相应上升,各组之间差异不显著。但试验Ⅱ组到试验后期体质量开始下降。试验组小鼠在饲喂棉酚2周后出现较明显的生理反应：拉稀、活动减少、被毛松散无光泽;试验结束,试验Ⅲ组小鼠解剖肾脏有出血点、质地变脆。试验Ⅳ组小鼠两侧肠膜变黄,腹膜变薄,胃肠蠕动较慢,肾脏有出血点现象。各组在第2周和试验结束后分别取样,发现试验组小鼠肾脏出现不同程度的病变。试验Ⅱ组小鼠肾脏病变较轻微,可试验Ⅲ组小鼠肾脏有不同程度的肾间质出血和肾小管上皮细胞颗粒变性坏死;试验Ⅳ组小鼠肾梗死、肾小球毛细血管扩张,充血,出血。结果表明：棉酚对小鼠的体增重有一定的抑制作用,但对肾脏的生理和病理损伤较大。     

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.