Using Artificial Neural Network to Predict Body Weights of Rabbits

In this (modest) study, we developed artificial neural network (ANN) models for predicting body weight using various independent (input) variables in eight-week old New Zealand white purebred and crossbred rabbits. From the whole data sets of similar age groups, 75 percent were used to train the neural network model and 25 percent were used to test the effectiveness of the model. Five predictor variables were used viz, breed, sex, heart girth, body length and height at wither as input variables and body weight was considered as dependent variable from the model. The ANN used was multilayer feed forward network with back propagation of error for efficient learning. Our ANN models (with R2 = 0.68 at ten thousand iterations, and R2 = 0.71 one million iterations) performed better than traditional multivariate linear regression (MLR) models (R2 = 0.66) indicating that the ANN models were able to more accurately capture how the variations in input variables explained the variations in body weight. It is concluded that ANN models are more powerful than MLR models in predicting animals’ body weight. Nonetheless, we recognize that fitting an ANN model requires more computation resources than fitting a tradition MLR model but the benefits of its accuracy outweigh any demerit from the associated computation overhead.

Effects of Dietary Lysine on Growth Performance, Serum Concentrations of Insulin-Like Growth Factor-I (IGF-I) and IGF-I mRNA Expression in Growing Rabbits

The effects of dietary lysine on production performance,serum concentrations of metabolites,growth hormone （GH）,insulin-like growth factor-I （IGF-I） and IGF-I mRNA expression in growing rabbits were examined.One hundred weaned New Zealand rabbits were allocated to individual cages and randomly offered a diet containing 5.5 （L1）,6.5 （L2）,7.5 （L3）,8.5 （L4）,or 9.5 g （L5） lysine per kg diet.The results showed that the average daily gain （ADG） of the rabbits from L3,L4 or L5 was higher than those from L1 or L2 （P 〈 0.05）.The feed gain ratio （F/G） in the rabbits from L4 or L5 was lower than those from L1 or L2 （P 〈 0.05）.Dietary lysine did not affect serum concentrations of total protein （TP）,glucose,insulin （INS）,and growth hormone （GH） （P 〉 0.05）.The quadratic effects of lysine on the serum urea nitrogen （SUN） concentration was detected （P = 0.035）.Serum IGF-I concentrations had a trend to increase quadratically with the increasing dietary lysine （P = 0.07）.A significant correlation was found between serum IGF-I concentrations （x,ng mL-1） and ADG （y,g kg-1）： y = -0.017x2 ＋ 1.984x ＋ 20.87 （R2 = 0.8982,P = 0.003）.The relative abundance of hepatic and muscular IGF-I mRNA tended to increase with increasing dietary lysine levels （P = 0.053 and 0.082,respectively）.Providing the diets mainly consisted of corn,wheat bran and peanut vine,the most appropriate dietary lysine level for growing meat rabbits from weaning to 70 d old was found to be 8.5 g kg-1,and IGF-I may be an important factor controlling growth of weaned rabbits.

Effect of sacubitril/valsartan on the expression of Gal-3 and MMP-9 in rabbits with cardiac hypertrophy

Objective:To investigate the effects of sacubitril/valsartan on the expression of Galectin-3 (Gal-3) and Matrix metalloproteinase-9 (MMP-9) in New Zealand rabbits with stress-induced cardiac hypertrophy.Methods: Twenty-four healthy male 8-week-old New Zealand rabbits were randomly divided into sham operation group (Sham), model group (Model), and sacubitril/valsartan group (Sacu/Vals), with 8 rats in each group. Abdominal aortic coarctation was used to construct a model of cardiac hypertrophy. After 8 weeks of successful modeling, the acubitril/valsartan group was administered with the drug, and the other two groups were given an equal volume of normal saline. All rabbit hearts were sacrificed at the end of the 16th week. The left ventricular mass index and the whole heart mass index were measured. The left ventricular myocardial tissue was evaluated by HE staining to evaluate the cardiac hypertrophy. The expression of Gal-3 and MMP-9 in the myocardial tissue was detected by western blot.Results: (1) Compared with the sham operation group, the HMI and LVMI of the model group and the sacubitril/valsartan group increased. Compared with the model group, the HBA and LVMI decreased in the sacubitril/valsartan group;(2) In the sham operation group, the myocardial fibers were arranged neatly, arranged in a bundle, and the morphology was intact, and no obvious fibrous tissue was observed. The myocardial fibers in the model group were disordered, most of them were broken, the cells were edematous, and the myocardial interstitial showed fibrous connective tissue. Compared with the model group, the sacubitril/valsartan group had a neat arrangement of myocardial fibers and a significant reduction in cell edema;(3) Compared with sham operation, the expression of Gal-3 and MMP-9 protein in the model group and the sacubitril/valsartan group increased;compared with the model group, sacubitril/valsartan the expression levels of Gal-3 and MMP-9 in the tan group were decreased.Conclusion: Sacubitril/valsartan can alleviate cardiac hypertrophy in rabbits, and its mechanism may be related to down-regulation of Gal-3 and MMP-9 protein expression.

Effect of different levels of dietary fiber on intestinal development and caecum fermentation traits of weaning rabbits

A common problem in rabbit production is the occurrence of digestive disorders just after weaning, and fiber is well known to be bcncficiai for rabbit gastrointestinal health. In order to test the hypothesis that whether the good points of fiber increases with its dietary content, three isoenergetic and isonitrogenous diets and ninety mixed-sex New Zealand rabbits weaned 35-d-old were used. The results can be concluded as following： （1） Average daily feed intake （ADFI） tended to increase （i〉=0.058） while average daily gain （ADG） （p=0.001） and feed conversion ratio （FCR） （p〈0.001） deteriorated with increasing dietary ADF content. The highest morbidity was observed in the rabbits fed the highest dietary ADF concentration. （2）A decreasing coefficient of total tract apparent digestibility （CTTAD） of dry matter （DM） and crude protein （CP） was obtained with the increase of dietary fiber level （p〈0.001 and =0.003）. （3） A significant negative effect of treatments on sucrase and maltase activities in the jejunum was observed （p=0.001 and 0.003）. （4） The volatile fatty acid （VFA） concentration （p=0.011） and butyric acid （% total VFA） （P=0.001） dropped while the NH3-N concentration （P〈0.001）, pH （P=0.004） and acetic acid （% total VFA） （P〈0.001） increased with increasing dietary ADF. It was concluded that high fiber level was unfavorable to the rabbits in the first two weeks after weaning.

White Rabbit Leaping Toward a New Field

You may still remember the story about the race between the big white rabbit and little tortoise, in which the over-proud rabbit lost. However, the White Rabbit toffees produced by the Shanghai Guansheng Yuan (Group) Co., Ltd. are famous-brand products in China. This White Rabbit not only is the cham-

Comparative study of a rabbit model of spinal tuberculosis using different concentrations of Mycobacterium tuberculosis

BACKGROUND Tuberculosis is among the most devastating infectious diseases worldwide.Spinal tuberculosis is not easy to detect at an early stage,which without effective treatment often leads to spinal deformity and spinal cord damage which in turn cause complications such as paraplegia and quadriplegia.In this study,we established a model using three concentrations of bacteria and carried out a comprehensive evaluation of the model by imaging,general observations,and histopathological and bacteriological studies.AIM To establish a rabbit model of spinal tuberculosis and examine the effect on the model’s efficacy using different concentrations of Mycobacterium tuberculosis(M.tuberculosis)inoculum.METHODS New Zealand rabbits were randomly divided into experimental,control and blank groups.The experimental and control animals were sensitized with complete Freund′s adjuvant,a hole was drilled beneath the upper endplate of the L6 vertebral body and filled with gelfoam sponge.The experimental group was divided into three subgroups(experimental 1,experimental 2,experimental 3)and infused with M.tuberculosis suspension at various concentrations.The control group was inoculated with saline and the blank group received no treatment.The 12-week post-operative survival rates were 100%,80%and 30%in the experimental groups inoculated with concentrations of 106,107 and 108 CFU/mL bacteria,respectively.RESULTS The survival rate of the control and blank groups was 100%.Vertebral body destruction at 8 weeks in the three experimental groups as determined by X-ray analysis was 33.3%,62.5%and 66.7%,and by computed tomography(CT)and 3-dimensional CT 44.4%,75%and 100%,respectively.At 12 weeks,the figures were 44.4%,75%and 100%by X-ray analysis and 44.4%,100%and 100%by CT and 3-dimensional CT,respectively.All surviving rabbits of the experimental groups had vertebral destruction.The positive bacterial culture rates were 22.2%,75%and 66.7%,respectively,in the experimental groups.After being sensitized with complete Freund's adjuvant,large differences were observed in the extent of spinal tuberculosis after inoculation of the rabbits with different concentrations of H37RV standard M.tuberculosis.CONCLUSION The experimental 1 had a low success rate at establishing an infection.The experimental 3 resulted in high mortality and complication rates.The experimental 2 was optimum for establishing a spinal tuberculosis model based on the high level of symptoms observed and the low rabbit mortality.

X射线透视引导下不同方式建立兔椎间盘退变模型的结果对比

背景:国内外学者认为新西兰大白兔腰椎解剖形态与人类腰椎更为相似,是理想的模型动物。在X射线引导下采用不同方式建立兔椎间盘退变模型目前尚缺乏系统性比较。目的:基于X射线引导采用针刺法、终板注射法以及改良终板注射法建立兔腰椎间盘退变模型,比较3种方法造模的效果。方法:6月龄新西兰大白兔16只随机分为4组,分别为针刺组、终板注射组、改良终板注射组及空白对照组,针刺组对3个连续节段(L2/3、L3/4、L4/5)椎间盘进行针刺造模,终板注射组在3个连续节段终板单点注射50μL无水乙醇,改良终板注射组对3个连续节段椎间盘进行针刺并在相应节段终板4个方位点注射50μL无水乙醇,空白对照组不进行干预。术后2,4,8周进行X射线检查,测量椎间隙高度指数,然后取椎间盘组织进行解剖学观察、病理学检查。结果与结论:①解剖学观察显示,针刺组以纤维环破溃为主要表现,终板注射组主要以髓核退变为主要表现,改良终板注射组以全椎间盘结构紊乱为主要表现;②与空白对照组相比,针刺组术后2周椎间隙高度指数降低最明显,终板注射组术后2,4周椎间隙高度指数降低明显,改良终板注射组术后2,4,8周椎间隙高度指数均显著降低;③病理学检查显示,针刺组纤维环结构出现破损,内层纤维环向内凸入,终板注射组表现为终板裂隙、排列混乱及细胞核丢失,改良终板注射组表现为整体椎间盘结构紊乱,髓核失水皱缩,与破损的纤维环无明显边界。结果表明,针刺法、终板注射法及改良终板注射法均能建立兔椎间盘退变模型,改良终板注射法较单一方法可大幅加快并加重椎间盘退变,可有效缩短实验周期。

自体骨移植联合生龙接骨方剂修复兔骨缺损实验研究

目的观察自体骨移植联合生龙接骨方剂对新西兰兔骨缺损模型修复效果的影响。方法选取54只SPF级6月龄雄性新西兰兔作为研究对象,随机分为单纯自体骨移植组(A组)、单纯生龙接骨方剂组(B组)、生龙接骨方剂联合自体骨移植组(C组),每组18只。各组均采用单侧桡骨中段临界尺寸法构建骨缺损模型,A、C组均予以自体骨移植,B、C组均灌胃生龙接骨方剂20 mg/(kg·d),A组灌胃等量生理盐水,持续干预1个月。于术后第1、2、3个月后分别分批处死实验兔,每组每次6只,收集桡骨组织,观察其损伤情况,采用苏木素-伊红(HE)染色、Masson染色检测桡骨愈合情况,经Micro-CT扫描测定各组实验兔骨组织体积(BV)、骨小梁数(Tb.N)、骨小梁厚度(Tb.Th)、骨小梁间距(Th.Sp)和骨密度(BMD)。结果术后各组大体观察到缺损断端骨痂形成至骨皮质连接的骨愈合过程,HE染色显示1~3个月各组炎性细胞浸润减少,C组较其他两组有较好的成骨作用。Masson染色结果显示,C组颜色对比鲜明,结构清晰,可以清晰地区分成熟骨质与新生骨质。Micro-CT检测结果显示,三组术后第2、3个月的BV、Tb.N、Tb.Th、BMD均高于本组术后1个月,B、C组术后3个月的BV、Tb.N、Tb.Th、BMD均高于本组术后2个月,差异有统计学意义(P<0.05)。术后第1、2、3个月,B、C组BV、Tb.N高于A组,C组BMD高于A组,BV、Tb.N、BMD高于B组,差异有统计学意义(P<0.05);术后第1、2、3个月,三组Tb.Th、Tb.Sp比较,差异无统计学意义(P>0.05)。结论自体骨移植联合生龙接骨方剂修复骨缺损效果明显,可提高新西兰兔成骨能力。

短串联重复序列扫描技术对无特定病原体新西兰兔遗传结构的分析

应用STR扫描技术,对广东省医学实验动物中心SPF级新西兰兔进行遗传检测和分析,以掌握该兔群体遗传结构,为制定繁殖育种方案提供依据,并为兔遗传分析方法提供参考。试验采集33只种兔耳静脉血,提取基因组DNA,选用多态丰富的23个微卫星位点对基因组DNA进行PCR扩增,扩增产物进行STR扫描,扫描结果运用popgene32软件分析群体观察等位基因数、有效等位基因数、香隆指数和有效杂合度等遗传结构信息。结果显示,全部23个微卫星位点PCR扩增良好,兔群体平均观测等位基因数为1.5217,平均有效等位基因数为1.2786,平均香隆指数为0.2442,平均有效杂合度为0.1564。初步掌握了该SPF级新西兰兔群体遗传结构。结果表明,STR扫描技术及选用的23个微卫星位点适用于兔群体遗传结构检测和分析,将为兔遗传分析方法提供参考和依据。

影响新西兰兔超数排卵及胚胎移植效果的研究

研究旨在探讨新西兰兔采用不同激素诱导超数排卵和胚胎移植效果的影响因素。试验考察不同激素[促卵泡激素(FSH)、孕马血清促性腺激素(PMSG)]、季节及经产与否等因素对母兔(供体)超数排卵效果的影响,并考察经产与否及同步发情方式对母兔(受体)胚胎移植效果的影响。结果显示,使用两种不同方案进行超排后,试验组Ⅰ母兔的排卵点总数、平均排卵点数、卵泡囊肿总数、平均卵泡囊肿数、可用胚胎总数、平均可用胚胎数、畸形胚胎数、胚胎畸形率均高于试验组Ⅱ(P>0.05),且两组中经产母兔平均排卵点数、平均可用胚胎数均显著高于青年母兔(P<0.05),春季进行超数排卵的平均排卵点数、平均可用胚胎数显著高于夏季(P<0.05)。经产母兔作为受体的妊娠率和产活仔数均高于青年母兔,但差异不显著(P>0.05)。光照调控组的妊娠率和产活仔数最高,但3组差异不显著(P>0.05)。研究表明,春季使用经产母兔为供体,采用60 IU PMSG进行超数排卵处理,通过光照调控同步发情,以经产母兔为受体进行胚胎移植,受孕率和产活仔数最佳。

不同血清型猪链球菌对新西兰兔的致病性研究

【目的】探究不同血清型猪链球菌(Streptococcus suis,SS)在新西兰兔体内的分布规律及致病性差异,为猪链球菌病的防治提供参考。【方法】分别采用SS1 ZY194株、SS2 QH株、SS7 ZY188株感染新西兰兔,通过临床症状观察,HE染色分析病理组织变化;利用实时荧光定量PCR检测脏器载菌量;通过试剂盒检测血清与肝脏生化指标变化;利用ELISA检测相关炎症因子的表达水平。【结果】3个试验组中,SS2组新西兰兔的临床症状表现与脏器的病理变化程度最明显。试验组新西兰兔各脏器均载菌,其中SS2组各脏器载菌量高于SS1和SS7组,且脾脏是载菌量最高的器官。各试验组新西兰兔葡萄糖(GLU)、甘油三酯(TG)、总胆固醇(TCHO)、低密度脂蛋白(LDL)和尿酸(UA)含量极显著或显著高于对照组(P<0.01;P<0.05),SS2和SS7组新西兰兔高密度脂蛋白(HDL)含量极显著低于对照组(P<0.01)。各试验组新西兰兔谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)、脂肪酶(LPS)含量及炎症因子IL-6、IL-1β、TNF-α的表达水平极显著或显著高于对照组(P<0.01;P<0.05),其中SS2组各指标的含量最高。【结论】不同血清型猪链球菌均可引起新西兰兔发病,其中SS2 QH株致病性最强。试验结果为猪链球菌病的致病机理研究提供借鉴,为临床防治该病提供理论基础。

猪链球菌2型在感染兔体内的分布及其致病性研究

猪链球菌(Streptococcus suis,SS)是一种重要的人畜共患病原体,猪链球菌2型(Streptococcus suis type 2,SS2)1954年首次在英国分离鉴定,在我国和其他养猪业发达的国家已多次流行,已成为危害我国养猪业和公共卫生安全的一个重要传染病。本研究用SS2-ZY05719株按10^(9)、10^(8)、10^(6)CFU腹腔注射途径人工感染健康的新西兰兔,3种剂量均可引起发病并死亡,新西兰兔临床症状明显,感染组平均体温升高1℃~2℃。同时分析了SS2在兔体各组织中的分布,结果显示,高剂量感染组出现明显的临床症状且快速死亡,感染剂量与发病程度有正相关性,对各试验组新西兰兔内脏组织进行检测发现,SS2主要集中在心脏、肝脏、脾脏、肺脏、肾脏和脑等组织中,不同组织器官中的细菌载量也存在着一定的差异,本文研究了SS2感染新西兰兔后的临床症状和各组织载菌量,为猪链球菌的防治及致病机理研究提供参考。

变应性鼻炎相关动物模型研究进展

目的综述变应性鼻炎(allergic rhinitis,AR)相关动物模型的研究进展,为深入研究AR的发病机制及药物评价提供参考。方法通过对国内外文献的查阅,从AR模型动物的种类、特点、模型种类、建模方法、模型成功的标准和评价指标等方面进行总结。结果变应性鼻炎相关动物模型包括西医病理模型和中医病症结合模型,动物选择多使用豚鼠、小鼠、大鼠、新西兰兔等。结论总结已有AR动物模型的种类、方法和评价指标以及在AR发病机制研究中的应用,可为后续AR的深入研究提供参考。

基于CREB3L1探讨矾冰纳米乳对兔耳增生性瘢痕模型相关蛋白及炎症因子的影响

目的观察矾冰纳米乳对兔耳增生性瘢痕组织环腺苷酸应答元件结合蛋白3样1(CREB3L1)及炎症损伤的影响,探讨其预防增生性瘢痕的作用机制。方法将30只新西兰大耳白兔随机分为空白组、模型组、积雪草苷组及矾冰纳米乳低、中、高剂量组(8.15、16.3、32.6 mg·mL^(-1))。采用热力烫伤法进行造模,深Ⅱ度烧伤造模成功后第14天给予相应药物外用,空白组、模型组外用等量生理盐水,每日2次,连续给药至第35天。苏木素-伊红(HE)染色观察兔耳瘢痕组织病理学改变;马松(Masson)染色观察瘢痕组织胶原沉积情况;免疫荧光双标法检测兔耳瘢痕组织CREB3L1/α-平滑肌肌动蛋白(α-SMA)共表达情况;酶联免疫吸附测定法(ELISA)检测瘢痕组织白细胞介素6(IL-6)、白细胞介素10(IL-10)等炎性因子表达;实时荧光定量聚合酶链式反应(Real-time PCR)检测CREB3L1、Ⅰ型胶原蛋白(COL-Ⅰ)、Ⅲ型胶原蛋白(COL-Ⅲ)、α-SMA mRNA表达;蛋白免疫印迹法(Western Bolt)检测CREB3L1、COL-Ⅰ、COL-Ⅲ、α-SMA的蛋白表达情况。结果与空白组比较,模型组瘢痕增生指数明显升高(P<0.01);病理学改变包括真皮层增厚,形成致密的网状纤维,伴见炎症细胞浸润;Masson染色可见真皮层增厚,蓝染的胶原纤维大量沉积排列紊乱;免疫荧光双标结果显示,瘢痕组织中CREB3L1阳性表达增加,α-SMA阳性表达增加,IL-6含量明显升高(P<0.01),IL-10含量明显降低(P<0.01),兔耳瘢痕组织中的CREB3L1、COL-Ⅰ、COL-Ⅲ、α-SMA mRNA相对表达量明显增加(P<0.01),CREB3L1、COL-Ⅰ、COL-Ⅲ、α-SMA蛋白的表达明显增加(P<0.01)。与模型组比较,矾冰纳米乳中、高剂量组及积雪草苷组治疗后瘢痕增生指数均明显下降(P<0.05,P<0.01),病理改变可见真皮层变薄,炎性细胞均有不同程度减少,蓝染的胶原纤维减少,免疫荧光双染可见瘢痕组织中CREB3L1阳性表达降低,α-SMA阳性表达降低,IL-6含量明显降低(P<0.01),IL-10含量明显升高(P<0.01),矾冰纳米乳中、高剂量组和积雪草苷组均能够明显下调CREB3L1、COL-Ⅰ、COL-Ⅲ、α-SMA mRNA的表达(均P<0.01),降低CREB3L1、COL-Ⅰ、COL-Ⅲ、α-SMA蛋白的表达(P<0.05,P<0.01)。结论矾冰纳米乳能够通过调节CREB3L1及相关纤维化蛋白的表达,降低炎症水平,从而预防增生性瘢痕形成,丰富了中医“既病防变”“治未病”思想的科学内涵。

新西兰白兔BMP 15基因的真核表达载体构建、表达模式及其在卵巢组织的表达

旨在获得新西兰白兔BMP 15基因序列及其组织表达规律,构建其真核表达载体,预测BMP15的生物学功能。本研究选择180日龄性成熟的健康新西兰白兔作为研究对象,采用RT-PCR技术扩增BMP 15基因CDS区序列,利用T4连接方法将目的片段连接至线性化的Pmcherry-N1和pCMV-Myc空载体,构建真核表达载体,利用生物信息学分析其编码蛋白的性质及结构。采用实时荧光定量PCR(qRT-PCR)技术与Western blotting技术检测pCMV-Myc-BMP 15过表达情况。接下来,使用qRT-PCR检测BMP 15基因在不同组织中的表达水平。激光共聚焦方法检测BMP 15基因的亚细胞定位。利用免疫荧光技术检测内源BMP15在新西兰白兔卵巢组织定位情况。结果表明:克隆得到新西兰白兔BMP 15基因CDS区序列长1182 bp,PCR及测序结果表明pCMV-Myc-BMP 15和Pmcherry-N1-BMP 15真核表达载体构建成功。生物信息学分析显示,BMP 15基因编码393个氨基酸;BMP15蛋白不稳定系数为55.32,等电点大小为9.69,是一种稳定的碱性蛋白质。BMP15蛋白共有26个磷酸化位点,15个糖基化位点,存在信号肽,不存在跨膜结构域。系统进化树表明,新西兰白兔与猪亲缘关系最近,与鸡的亲缘关系最远。二级结构和三级结构分析结果表明,BMP15蛋白主要由α-螺旋(38.68%)、无规则卷曲(37.4%)、延伸链(15.52%)、β-转角(8.40%)组成,为混合型蛋白。蛋白互作关系预测发现,BMP15蛋白与FSHR、FIGLA、BMPR1B、AMHR2、NOBOX等卵巢生长发育的相关蛋白之间存在相互作用。不同组织表达分析显示,BMP 15基因在卵巢组织中特异性表达;激光共聚焦结果显示,BMP15主要存在于在细胞质中。将pCMV-Myc-BMP 15转染至HEK293T细胞内,BMP15的mRNA水平和蛋白水平均显著上调。卵巢组织免疫荧光检测结果显示,BMP15主要定位在卵巢颗粒细胞的细胞质中。本研究成功构建了BMP15的真核表达载体,对BMP 15基因及其编码的蛋白的理化性质和生物学特性进行了预测分析,在HEK293T细胞内成功过表达,并得到了该基因的亚细胞定位情况、组织表达情况及在卵巢组织的分布情况。为后续开展BMP 15基因在卵巢生长发育中的功能及机制研究提供了理论依据。

新西兰兔下丘脑qPCR内参基因的筛选和验证

为筛选适合新西兰白兔下丘脑的最佳内参基因,试验选定甘油醛-3-磷酸脱氢酶(GAPDH)、肌动蛋白β(ACTB)、β-2-微球蛋白(B2M)、酪氨酸3-单加氧酶(YWHAZ)、次黄嘌呤磷酸核糖转移酶1(HPRT1)、核糖体蛋白L4(RPL4)和TATA-box结合蛋白(TBP)共7个候选内参基因,利用实时荧光定量PCR(qPCR)技术对不同年龄、性别及发情状态的新西兰白兔下丘脑组织的基因表达水平进行检测;通过RefFinder在线软件综合ΔCt、GeNorm、NormFinder和BestKeper等4种算法的分析结果来评估内参基因表达的稳定性,并选取在下丘脑表达的功能基因雌激素受体(ER1)、孕激素受体(PGR)和RFamide神经肽VF(NPVF)对候选内参基因稳定性和评价结果的可靠性进行验证。结果:不同年龄的雌性新西兰白兔下丘脑稳定表达的内参基因是YWHAZ和GAPDH;雄性新西兰白兔下丘脑稳定性表达的内参基因YWHAZ和TBP,而不同发情期新西兰白兔适合使用HPRT1和YWHAZ作为内参基因。当使用不同内参基因进行标准化时,目的基因表达水平受到样本不同生理状态而出现明显变化,强调了先行验证内参基因对于qPCR研究基因表达水平的重要性。

基于MAPK信号通路探讨复方芪芎颗粒对IL-1β诱导的兔骨关节炎软骨细胞的作用及其机制

目的:基于MAPK信号通路探讨复方芪芎颗粒对IL-1β诱导的兔骨关节炎软骨细胞的作用及其机制。方法:选取5只清洁级新西兰大白兔,提取兔软骨细胞培养至第2代,通过IL-1β诱导软骨细胞,建立骨关节炎软骨细胞体外模型,将其分为空白对照组、IL-1β组、双醋瑞因组、复方芪芎颗粒低浓度组、复方芪芎颗粒中浓度组、复方芪芎颗粒高浓度组。空白对照组不进行任何干预,IL-1β组采用质量浓度为10μg/L的IL-1β处理,双醋瑞因组采用10-5mol/L双醋瑞因处理,复方芪芎颗粒低、中、高浓度组分别采用10 mg/mL、20 mg/mL、30 mg/mL复方芪芎颗粒处理。干预24、48、72 h后,采用实时荧光定量逆转录聚合酶链式反应(RT-qPCR)检测各组P38激酶、c-Jun氨基端激酶(JNK)、细胞外信号调节蛋白激酶(ERK)、P65激酶、基质金属蛋白酶13(MMP-13)基因表达水平;干预72h后,采用Western blotting法检测各组P38、JNK、ERK、P65、MMP-13蛋白表达水平。结果:干预24、48、72 h后,IL-1β组P38 mRNA、JNK mRNA、ERK mRNA、P65 m RNA、MMP-13 mRNA相对表达量高于空白对照组(P<0.05);双醋瑞因组和复方芪芎颗粒低、中、高浓度组P38 mRNA、JNK mRNA、ERK mRNA、P65 mRNA、MMP-13 mRNA相对表达量均低于IL-1β组(P<0.05);复方芪芎颗粒高浓度组P38 mRNA、JNK mRNA、ERK m RNA、P65 mRNA、MMP-13 mRNA相对表达量低于复方芪芎颗粒低浓度组(P<0.05)。随着药物干预时长的延长,双醋瑞因组和复方芪芎颗粒低、中、高浓度组P38 mRNA、JNK mRNA、ERK mRNA、P65 m RNA、MMP-13 mRNA相对表达量均呈降低趋势(P<0.05)。干预72 h后,IL-1β组P38、JNK、ERK、P65、MMP-13蛋白相对表达量高于空白对照组(P<0.01);双醋瑞因组和复方芪芎颗粒低、中、高浓度组P38、JNK、ERK、P65、MMP-13蛋白相对表达量均低于IL-1β组(P<0.01);复方芪芎颗粒高浓度组P38、JNK、ERK、P65、MMP-13蛋白相对表达量低于复方芪芎颗粒低浓度组(P<0.01)。结论:复方芪芎颗粒对IL-1β诱导的骨关节炎软骨细胞具有保护作用,其机制可能是通过抑制MAPK信号通路实现的,且随着药物浓度的升高和干预时长的延长其对MAPK信号通路的抑制效果更加明显。

一例新西兰白兔系统性淀粉样变性病理学诊断

目的通过1例新西兰白兔系统性淀粉样变性的病理学诊断,为实验动物淀粉样变性的诊断提供参考。方法在一项为期6个月的重复滴眼给药毒性试验中,发现1只新西兰白兔的常规大体解剖检查异常,随后将其各脏器组织制作成石蜡切片,进行苏木素-伊红(hematoxylin-eosin,HE)染色和刚果红染色,于光学显微镜和偏振光显微镜下观察其病理组织学特征。结果大体解剖后肉眼形态观察见该例动物的脾脏偏大,肺脏颜色和质地改变。对各脏器组织进行HE染色后显示:脾脏组织结构被破坏,脾脏白髓周围被致密淀粉样沉积物以结节环的形式包围,白髓可见压力性萎缩;颌下淋巴结、肠系膜淋巴结以及回肠、圆小囊、蚓突、空肠、盲肠和直肠亦可见淀粉样蛋白沉积。刚果红染色显示,各受影响脏器组织内淀粉样蛋白呈鲑鱼粉色,在偏振光显微镜下呈现特殊的苹果绿双折光。结论该例新西兰白兔的各脏器组织病理特征符合系统性淀粉样变性的诊断特征。

同种异体骨软骨移植的新西兰兔动物模型建立与评价

目的建立同种异体骨软骨移植的新西兰兔动物模型,并评估其影像学及组织学特征。方法选取5个月龄新西兰兔共36只,雌雄不限,随机选取12只取右后肢膝关节,经处理后截取部分胫骨平台骨软骨组织做为同种异体骨软骨移植的供体。12只为实验组,在右后肢膝关节胫骨侧截取5 mm×5 mm×5 mm骨软骨缺损区,同种异体骨软骨组织截取等量组织移植固定;12只为对照组,在右后肢膝关节胫骨侧相同位置截取等量骨软骨后原位固定。术后X线评估骨愈合情况,取材后microCT评估骨小梁愈合情况,骨关节切片染色观察组织学变化。结果两组动物均存活良好,无术后并发症;术后4周X线片示骨愈合良好;术后6周膝关节取材后microCT显示截骨处骨性愈合良好;关节切片HE染色显示软骨及软骨下骨结构良好,两组关节厚度无明显差异,番红固绿染色Mankin评分两组差异无统计学意义,阿利新兰染色显示活性软骨细胞计数两组差异无统计学意义。结论新西兰兔膝关节同种异体骨软骨移植动物模型构建简单、操作性强、手术并发症少,可较好地反应同种异体骨软骨移植的病理及生理过程。

Ⅱ型糖尿病兔大脑皮质和海马神经元的神经丝蛋白表达(英文)

Objective:To investigate the morphological changes of the neuronal neurites in diabetic rabbit brain. Methods: Twenty- four New Zealand White rabbits were divided into 2 groups: control group and type Ⅱ diabetic group induced by high - carbohydrate and high- fat diet. The levels of blood sugar and insulin were detected at week 0(w0), w4, w8, w13, w18, w23 and w28. Brain tissue was stained by Nissl staining and immunolistochemistry with a specific antibody to neurofilament proteins. Result: In diabetic rabbits, the amount of large pyramidal neuron was significantly reduced, and neuronal neurites became swollen, whorled, disrupted and changed in caliber. In hippocampus CA1 region neurofilament staining was very weak. Conclusion: Neurotoxicity of chronic hyperglycemia might be relevant to vascular chronic complications, which affected the expression of NF and led to neurophysiological and structural changes in the brain of rabbits with type Ⅱ diabetes.