蜥蜴利什曼原虫在小鼠体内的分布及增殖研究

通过腹腔途径用体内含有荧光蛋白的蜥蜴利什曼原虫感染BALB/c小鼠,感染后采其脏器做冰冻切片,荧光染料染色后用荧光显微镜观察,并经PCR鉴定,结果显示蜥蜴利什曼原虫感染小鼠后,主要分布于心脏、肝脏、脾脏、肺脏、肾脏。另外,成功建立了利什曼原虫荧光定量PCR检测方法,并采用该方法检测感染蜥蜴利什曼原虫后BALB/c小鼠体内利什曼原虫的增殖情况,结果显示,感染13 d内,BALB/c小鼠体内蜥蜴利什曼原虫呈波浪状增殖。这一结果为研究蜥蜴利什曼原虫感染人和动物的致病机理和免疫方法及疫苗研制等方面提供了基础理论依据。     

Bronchoalveolar lavage affects computed tomographic and radiographic characteristics of the lungs in healthy dogs

Bronchoalveolar lavage is a common diagnostic test for dogs with suspected pulmonary disease, however there is no published information on whether this procedure could affect the imaging characteristics of the lungs. Aims of this prospective experimental study were to describe computed tomography (CT) and radiographic features of the lungs after bronchoalveolar lavage in a sample of healthy dogs. Thoracic CT and radiographic images of eight healthy Beagles were acquired at the following time points: before bronchoalveolar lavage, immediately following bronchoalveolar lavage, and at 2, 4, 8, 12, and 24 h following bronchoalveolar lavage. Lung consolidation or interstitial patterns were seen in CT and radiographic images immediately after the procedure. Radiographic lung patterns resolved within 2 h and CT patterns resolved within 24 h. Resolution of the CT pulmonary patterns in the ventral areas of the lungs was delayed compared to the dorsal areas. Mean CT imaging scores differed over time (P < 0.001), while mean radiographic imaging scores did not differ over time. This study suggests that thoracic radiography and CT imaging assessments should precede bronchoalveolar lavage procedures if possible, or be performed at least 24 h afterward.     

Radiographic,ultrasonographic, and computed tomographic characteristics of an accessory liver lobe in a cat

A 5‐year‐old male Norwegian Forest cat presented with increased hepatic serum biochemical parameters. Abdominal radiography showed an oval cranioventral mass and ultrasound revealed a mobile mass attached to one hepatic lobe. Computed tomography (CT) confirmed that the mass was attached to the right medial liver lobe. Differential diagnoses were an accessory liver lobe, benign neoplasia, and focal nodular hyperplasia. The mass was removed and histopathology confirmed the mass to be normal liver tissue. Accessory liver lobe should be included in the differential diagnosis of a mobile cranial abdominal mass with a similar ultrasonographic or CT appearance to the liver.     

Tissue-specific expression of the NOD-like receptor protein 3 in BALB/c mice

Activation of the innate immune system requires recognition of pathogen-associated molecular patterns, such as NOD-like receptors. The NOD-like receptor protein 3 (NLRP3) inflammasome is involved in induction of the pro-inflammatory cytokine, IL-1β, and subsequent inflammatory responses. NLRP3 inflammasome plays important roles in the inflammatory and innate immune responses associated with autoimmune/inflammatory syndrome. However, analysis of the tissue distribution and expression profiles in BALB/c mice is still incomplete. In this study, we investigated the tissue distribution and expression pattern of NLRP3 in BALB/c mice to further elucidate its function in innate immunity in this commonly used laboratory animal model. NLRP3 mRNA expression levels and tissue distribution of the protein were investigated by real-time quantitative PCR and immunohistochemical analyses, respectively. NLRP3 mRNA expression was higher in the kidney and inguinal lymph nodes than in other tissues. Cytoplasmic expression of NLRP3 was detected in the epithelial reticular cells of the spleen and thymus, lymphocytes in the inguinal lymph nodes, cardiac muscle cells, cerebral cortex neurons, alveolar macrophages, renal tubule cells and liver sinusoidal endothelial cells. The results of this study will assist investigators in interpreting site-specific functions and roles of NLRP3 in inflammatory responses.     

Computed tomographic anatomy of the canine cervical vertebral venous system

Computed tomographic (CT) venography of the cervical vertebral canal was performed in six, clinically normal, adult mixed-breed dogs from 14 to 23 kg. After dogs were euthanized and saline perfused, a gelatin and iothalamate mixture was injected into the right external jugular vein. Contiguous, 4-mm-thick CT images were obtained with dogs in sternal recumbency. Dogs were kept in the same position as for the CT scan and frozen to approximately -8 degrees C. All post-contrast CT images were analyzed using similar bone window and level settings. Additional multiplanar reformatted dorsal images were obtained in all dogs. The frozen cadavers were sectioned through the cervical region extending from the occiput to T1 at approximately 8-mm intervals. The frozen sections were then compared with the CT images. The CT appearance of the normal cervical vertebral venous system was described and illustrated. Components such as the internal vertebral venous plexus, interarcuate veins, intervertebral veins, and vertebral veins were clearly identified on the CT images.     

猪圆环病毒2型感染裸鼠及BALB/c小鼠的研究

用猪圆环病毒2型（PCV2）经腹腔注射BALB/c小鼠及裸鼠各15只,每隔2周1次,共感染3次.BALB/c小鼠初次、再次感染后均未出现明显的临床症状,仅有2只小鼠出现病理变化;从血清中可检测到PCV2核酸及其ORF2抗体;同时淋巴细胞增殖反应显著增强,NK和CTL细胞杀伤率显著升高;CD4^＋、CD8^＋、CD3^＋T淋巴细胞及CD19^＋B淋巴细胞数量显著减少.裸鼠也未出现明显的临床症状,从血清中可检测到PCV2核酸,但未检测到PCV2 ORF2抗体;除NK细胞杀伤率显著升高外,其余免疫学指标无显著改变.结果表明,BALB/c小鼠比裸鼠对PCV2易感,各项免疫学指标变化与PCV2感染猪一致,但不表现临床症状,仅个别BALB/c小鼠出现病理变化,说明BALB/c小鼠对PCV2不如猪易感.     

Cellular and humoral immune responses during intrathoracic paracoccidioidomycosis in BALB/c mice

Paracoccidioidomycosis is a chronic infection that primarily affects the lungs. Here we investigated cellular and humoral immune responses after intrathoracic Paracoccidioides brasiliensis infection in BALB/c mice. P. brasiliensis-colony-forming units (CFUs), fungal DNA and granulomas in lungs increased progressively, peaking at day 90 postinfection (p.i.). IFN-γ production was highest on day 15 p.i., declining thereafter. The kinetics of the NO production was similar to that described for IFN-γ. In contrast, IL-10 increased from day 45 p.i. reaching a peak at day 90. Levels of serum IgG1 were higher than IgG2a between days 30 and 90 p.i. 30% of mice died by day 90 p.i. These data indicate that infection with P. brasiliensis by the intrathoracic route shows high IFN-γ and NO production at day 15 p.i., unable to control multiplication of fungi, which appears to be associated with a progressive increase in IL-10 and in the number and complexity of granulomas.     

Computed tomographic anatomy of the temporomandibular joint in the young horse

Reasons for performing study: The equine temporomandibular joint (TMJ) and its surrounding structures can be difficult to investigate in cases with a clinical problem related to the region. Little previous attention has been given either to a computed tomographic (CT) imaging protocol for the joint or an interpretation of the structures displayed in CT images of the normal joint. Objectives: To provide a CT atlas of the normal cross‐sectional anatomy of the equine TMJ using frozen and plastinated sections as anatomical reference. Methods: Eight TMJs from 4 immature pure‐bred Spanish horses were examined by helical CT. Scans were processed with a detailed algorithm to enhance bony and soft tissue. Transverse CT images were reformatted into sagittal and dorsal planes. Transverse, sagittal and dorsal cryosections were then obtained, photographed and plastinated. Relevant anatomic structures were identified in the CT images and corresponding anatomical sections. Results: In the CT images, a bone window provided excellent bone detail, however, the soft tissue components of the TMJ were not as well visualised using a soft tissue window. The articular cartilage was observed as a hyperattenuating stripe over the low attenuated subchondral bone and good delineation was obtained between cortex and medulla. The tympanic and petrous part of the temporal bone (middle and inner ear) and the temporohyoid joint were seen in close proximity to the TMJ. Conclusions: Helical CT provided excellent images of the TMJ bone components to characterise the CT anatomy of the normal joint. Potential relevance: Detailed information is provided that may be used as a reference by equine veterinarians for the CT investigation of the equine TMJ and serve to assist them in the diagnosis of disorders of the TMJ and related structures (middle and inner ear). The study was performed at an immature stage and further studies of mature individuals are required in order to confirm that the clinical interpretation is not affected by changes occurring with age.     

LPS对BALB/c小鼠血清及肝脏铁状态的影响

采用血清铁和组织铁测定及ELISA方法检测了脂多糖(LPS)作用不同时间点小鼠血常规、血清铁含量、组织铁含量及血清转铁蛋白(Tf)含量变化.结果显示,与对照组相比注射LPS组红细胞计数(RBC)和血红蛋白含量(HGB)均显著下降(P＜0.05),但平均红细胞体积(MCV)和HGB含量在注射后1.5h组与对照组相比均无显著差异.结果表明,在注射LPS后1.5h没有形成小细胞低色素性贫血,即缺铁性贫血(IDA),在此时间点适合进行铁代谢研究.而在其他作用时间点,可能是由于RBC和HGB显著下降,从而使MCV代偿性增加.另外,在注射LPS后1.5h组白细胞计数(WBC)与对照组相比显著下降,是临床革兰阴性细菌感染的特征,而LPS是革兰阴性细菌细胞壁内毒素的主要成分,可见其在对小鼠作用1.5h时起到了有效作用,而其他时间点WBC与对照组相比均没有出现显著差异.     

流感病毒PR8F的拯救及其对BALB/c小鼠的致病力

为了研究H1N1流感病毒对BALB/c小鼠的致病相关分子机制、传播机制以及开发新型疫苗,将本实验室保存的A/PR/8/34株的8个质粒参照Paulina构建的流感病毒8质粒突变系统做定点突变,利用反向遗传操作技术,成功拯救出H1N1流感病毒突变株PR8F。将PR8F株以106 TCID50/100μL的剂量滴鼻感染BALB/c小鼠,观察小鼠临床表现及体质量变化。解剖攻毒后不同时间小鼠并观察体内主要脏器的病理特征,提取各脏器RNA,通过实时荧光定量PCR方法,检测PR8F株在小鼠体内不同脏器中的病毒残留量和在BALB/c小鼠肺脏中的扩增效率。结果表明,H1N1流感病毒突变株PR8F感染小鼠4~7d后全部致死;PR8F株在小鼠体内各脏器中的病毒残留量有很大差异,肺脏中最多,且病毒在肺脏内呈指数形式扩增。本试验建立了H1N1流感病毒PR8F株对BALB/c小鼠的感染模型,为H1N1流感病毒致病机制和传播机制的研究奠定基础。     

Comparison of computed tomographic and standard radiographic determination of tibial torsion in the dog

OBJECTIVE: To compare the effect of internal tibial rotation on the computed tomographic (CT) and standard radiographic assessment of tibial torsion (TT) in dogs. STUDY DESIGN: In vitro study. SAMPLE POPULATION: Cadaveric canine hind limbs (6 pairs). METHODS: The cranial cruciate ligament was transected, and caudo-cranial radiographic and transverse CT images were obtained with the femur and tibiae in a neutral position, and after 15 degrees internal tibial rotation. Radiographic TT was determined by measuring the distance (d) between the calcaneus and the sulcus of the talus. CT determination of TT was performed using the proximal transcondylar and the distal cranial tibial axes. The distance (d) in the 2 groups and the difference in the CT determination of TT between groups were compared with a hypothetical mean value of 0 mm and 0 degrees, respectively. RESULTS: The mean distance (d) for the neutral radiographic group was not significantly different from 0 (P=.473); however, for the 15 degree group it was significantly different (P<.0001). The difference in the CT determination of TT did not differ from 0 (P=.317). CONCLUSION: The standard radiographic technique does not discriminate between internal TT and internal rotation of the tibia. Thus, dogs with normal tibial conformation can be depicted by radiography as torsed, whereas dogs with TT may be misinterpreted as normal because of arbitrary positioning. CLINICAL RELEVANCE: Lateral displacement of the medial border of the calcaneus on a caudo-cranial radiograph should not be used as the sole arbiter of TT before surgical correction.     

SD大鼠和BALB/c小鼠PRND基因的克隆和序列分析

以睾丸总RNA为模板,运用RT-PCR方法扩增了SD大鼠和BALB/c小鼠的叠朊蛋白(PRND)基因,并将其克隆到pMD18-T载体中进行测序,运用生物信息学软件对这些序列进行了分析。结果表明获得的SD大鼠和BALB/c小鼠PRND基因的完整ORF片段,基因无内含子,分别编码178和179个氨基酸的前体蛋白。与GenBank登录的其他同品种鼠相应序列进行比较,SD大鼠发生了G187C点突变,相应地引起了G63R的氨基酸改变;BALB/c小鼠发生了G12T、C13G和C528T点突变,但只发生了L5V的氨基酸改变,其余均为同义置换。氨基酸一级结构分析显示2种PRND编码的Dopple蛋白均由氨基端的信号肽、中间的成熟蛋白和羧基端的GPI锚定结合区组成。二级结构预测表明,Dopple蛋白由3个α-螺旋和2个β-折叠片层组成。研究结果为进一步研究Dopple蛋白的结构、功能及其在传染性海绵状脑病发生发展中的作用提供了基础数据。     

Prevalence of clinical and subclinical middle ear disease in cats undergoing computed tomographic scans of the head

Three hundred and ten cats that had CT imaging of the head between January 2000 and December 2007 were evaluated retrospectively. Data that were recorded included signalment, presenting complaint, clinical signs, presence of upper respiratory tract disease, and CT findings. One hundred and one cats had evidence of middle ear disease on CT. Thirty-four of the 101 cats (34%) did not have a primary complaint of ear-related disease, clinical signs or physical findings consistent with ear disease, suggesting that the middle ear disease was subclinical. Twenty-seven of the 34 cats (79%) had concurrent nasal disease. Middle ear lesions were chronic in appearance. With the exception of tympanic bulla lysis, CT findings were similar in cats presenting with primary aural disease versus cats with presumptive subclinical middle ear disease. The majority of the cats did not return for treatment of the identified middle ear abnormalities. Subclinical middle ear disease is relatively frequent in cats undergoing CT imaging of the head. Few cats required subsequent treatment for ear disease although follow up was limited. Identification of subclinical middle ear abnormalities on CT should prompt acquisition of a detailed patient history and bilateral otoscopic examination.     

Immunogenicity of Brucella-extracted and recombinant protein vaccines in CD-1 and BALB/c mice

A study was conducted to determine whether subcomponent proteins (previously identified as BCSP20, BCSP31, and BCSP45, and the corresponding recombinant proteins rBCSP20, rBCSP31, and rBCSP45) that were recovered from the cell surface of Brucella abortus strain 19 were immunogenic and protective for mice when compared with Brucella cell surface protein (BCSP) and with a proteinase K-treated lipopolysaccharide (PKLPS) extracted from B abortus strain 2308. Protection was evaluated after challenge exposure with a virulent culture of B abortus strain 2308, using CD-1 or BALB/c mice or both inoculated with vaccines of various combinations and concentrations, with and without PKLPS or BCSP. Protection was assessed by enumeration of splenic colony-forming units, reduced mean splenic weight relative to controls, and the relative serologic responses (immune response) in an ELISA. The general results indicate that BCSP, PKLPS, BCSP20, and BCSP31 are immunogenic or protective or both. Protectiveness was not observed for each of the recombinant proteins; however, results from the combined recombinant protein vaccine study suggest the immunogenicity of the recombinant proteins. The apparent immune-inducing properties of BCSP20 and BCSP31 are thought to be attributable to the presence of an immunogenic and protective BCSP fraction (possibly lipopolysaccharide) still associated. Serologic results support our conclusion that each of the recombinant protein vaccines did not induce a protective response comparable to that of BCSP or PKLPS, even when the subcomponents were combined. Although the results suggest that the subcomponents of BCSP apparently induced partial protection, they are thought to be only a part of the antigens contained in BCSP that influence the serologic response.(ABSTRACT TRUNCATED AT 250 WORDS)     

Radiographic and computed tomographic evaluation of experimentally induced lung aspiration sites in dogs

This study was performed to radiographically examine the prevalence of aspiration sites and to evaluate their atomical correlation with the bronchial pattens. Ten healthy beagle dogs were repeatedly radiographed, at weekly intervals, in the left and right lateral, ventrodorsal (VD) and dorsoventral (DV) positions. Three mililiters of iohexol distilled with same volume of saline was infused into the tracheal inlet. Which lung lobe was aspirated was decided upon by the presence of a significant alveolar pattern due to the contrast medium. Alveolar patterns were identified at the left (100%) and right cranial lung lobes (77%) with the dogs in dependant lateral recumbency, at the right caudal lung lobe (71%) with the dogs in VD recumbency and at the right middle lung lobe (59%) with the dogs in DV recumbency, respectively. The anatomical correlation was evaluated by performing computed tomography. The right principal bronchus (165.8 ± 1.6°) was more straightly bifurcated than was the left principal bronchus (142.7 ± 1.8°, p < 0.01). In VD position, the right side lung had a greater opertunity to become aspirated. The ventrally positioned right middle lobar bronchial origin was more easily to be aspirated the other laterally positioned ones. We think that these anatomical characteristics can be one of the causes for aspiration pneumonia to occur more frequently in the right side lung.