家兔腓肠肌和胫前肌NADH-TR染色的探讨

研究成年家兔腓肠肌内外侧头和胫前肌的肌纤维构成比例与分布.应用烟酰胺腺嘌呤二核苷酸四唑氧化还原酶（NADH-TR）染色法,观察比较各型肌纤维的组织化学特性.结果表明：NADH-TR染色,依据其肌纤维内线粒体和肌质网显示紫色或紫蓝色,肌原纤维中的肌动蛋白和肌球蛋白不着色,可以分为Ⅰ型、ⅡA型、ⅡB型肌纤维,横切面呈多边形或椭圆形,以镶嵌交叉方式排列.三种类型的肌纤维在腓肠肌内侧头中分别约占15.2%,27.4%和57.4%,在站立负荷中提供足够肌力和稳定机体姿势的作用;在腓肠肌外侧头中分别约占13.7%,65.4%和20.9%,主要参与力量和速度运动,提供奔跑,跳跃中的推进动力;在胫前肌中约占10.9%,52.3%和36.8%,维持跗关节稳定,参与保持足弓形状与弹性,完成足跖屈和足内翻运动.腓肠肌内外侧头和胫前肌的三型肌纤维直径有所差异,其中Ⅰ型纤维为57.50～58.40 μm,ⅡA型纤维为59.25～75.40 μm,ⅡB型纤维为73.25～97.85 μm.ⅡB型纤维的横切面积最大,ⅡA型纤维的横切面积中等,Ⅰ型纤维的横切面积最小.     

Phenotypic description of multiple congenital ocular anomalies in Comtois horses

Multiple congenital ocular anomalies (MCOA) and their relation to coat colour genotype have not yet been described in Comtois horses, unlike in Rocky Mountain Horses. The objectives of the study were to describe prevalence, nature and severity of congenital ocular anomalies relating to the PMEL17 (Silver) mutation in Comtois horses. Seventy‐four purebred Comtois and one half‐cross Comtois horses, aged 10 days to 18 years, were examined by transillumination, direct ophthalmoscopy and ultrasonography. Hair samples were collected from 34 horses for coat colour genotyping. Sixty‐six horses (88%) revealed cysts (65 horses) or abnormal thickness (one horse) of the ciliary bodies, most of them only diagnosed by ultrasonography. Cysts were localised in the nasal part of the eye in 8 horses. All these horses presented the silver phenotype with mane and tail being white or flaxen, or were chestnut with genetic testing confirming PMEL17 mutation. Of these, 39 (58%) showed MCOA‐syndrome with iridal hypoplasia (100%), cataract (85%), cornea globosa (56%) and lens luxation (8%). Only 8 bay mature horses (11%) were classified as being disease‐free. Genetic testing confirmed that cyst‐phenotype horses were heterozygous carriers for the Silver mutation, MCOA‐phenotype horses were homozygous carriers, and bay horses were noncarriers. Bay homozygous carriers had significantly lighter coat colour than heterozygous carriers. One foal with heterozygous mutation had normal eyes. Thus, MCOA‐syndrome related to PMEL17 mutation is overrepresented in Comtois horses, and should be taken into consideration for breeding purposes. Ultrasonography permitted detection of cysts in all Silver carriers apart from one, some of them being localised in the nasal part of the eye.     

Infrared digital imaging of the equine anterior segment

Ocular photographs are an increasingly important method of documenting lesions for inclusion in medical records, teaching purposes, and research. Availability of affordable high-quality digital imaging equipment has allowed for enhanced capture of desired images because of immediate on-camera viewing and editing. Conversion of the standard digital camera sensor to one that is sensitive to infrared light (i.e. > 760 nm < 1 mm wavelength) can be done inexpensively. In the equine eye, advantages of infrared digital photography include increased contrast of anterior segment images, identification and monitoring of pigmentary changes, and increased visualization of the anterior segment through a cloudy or edematous cornea.     

Brucella canis endophthalmitis in 3 dogs: clinical features, diagnosis, and treatment

Objective  To describe historical, clinical and diagnostic features of dogs with Brucella canis endophthalmitis and the response to medical therapy.
Animals studied  Three dogs with naturally acquired B. canis endophthalmitis.
Procedure  Dogs were treated symptomatically with topical ophthalmic anti-inflammatories and a novel antimicrobial protocol that included doxycycline, enrofloxacin, rifampin and streptomycin.
Results  All dogs presented with chronic or recurrent uveitis in the absence of overt systemic disease. Clinical ophthalmologic abnormalities were unilateral in each dog and included mild-to-moderate anterior uveitis, iris hyperpigmentation, marked vitreal infiltrates, and multifocal chorioretinitis. Dogs were diagnosed with canine brucellosis serologically and by blood culture ( n  = 2 dogs) or polymerase chain reaction of aqueous humor and blood ( n  = 1 dog). Active ocular inflammation resolved in all dogs during treatment, with preservation of vision in 2 dogs. Following treatment, B. canis could not be cultured from blood samples and serological values declined with seronegativity achieved in all dogs after a median of 96 weeks (range: 36–112 weeks) of therapy.
Conclusions  Brucella canis infection should be included in the differential diagnosis for dogs with intraocular inflammation, regardless of previous history or neuter status. This is the first report of apparently successful medical therapy of canine brucellosis with ocular involvement.     

Characterization of cytokines associated with Th17 cells in the eyes of horses with recurrent uveitis

Objective Equine recurrent uveitis (ERU) is a spontaneous disease that is the most common cause of blindness in horses, affecting up to 15% of the horse population. Th17 cells are a major cell population driving the pathogenesis in several mouse models of autoimmune inflammation, including experimental autoimmune uveitis. The purpose of this study is to investigate the role a Th17 cell‐mediated response plays in the pathogenesis of ERU. Procedure Banked, Davidson’s‐fixed equine globes histopathologically diagnosed with ERU (n = 7) were compared immunohistochemically with healthy control globes (n = 7). Immunohistochemical staining was performed using a pan‐Leptospira antibody and antibodies against IL‐6, IL‐17, and IL‐23. Additionally, immunostaining was performed for T‐cell (CD3) and B‐cell (CD79α) markers. Specificity of immunoreactivity was confirmed by western blot analysis. Results Immunohistochemical staining was positive for IL‐6, IL‐17, and IL‐23 within the cytoplasm of nonpigmented ciliary epithelial cells and mononuclear inflammatory cells infiltrating the iris, and ciliary body of ERU horses (n = 7) but negative in controls (n = 7). ERU‐affected eyes were CD3 positive (n = 7) and CD79α negative (n = 7). Staining for Leptospira was negative in all ERU and control globes. Conclusions Strong immunoreactivity for IL‐6, IL‐17, and IL‐23, in conjunction with the fact that T lymphocytes are the predominating inflammatory cells present in ERU, suggests that IL‐17‐secreting helper T‐cells play a role in the pathogenesis of ERU. These findings suggest that horses with ERU may serve as a naturally occurring animal model for autoimmune uveitis.     

Lens-induced uveitis

Lens-induced uveitis has been described in humans and many animal species. Traumatic rupture of the lens capsule may result in vision-threatening intraocular inflammation that is poorly responsive to medical management. Phthisis bulbi, persistent uveitis or glaucoma often occurs in these eyes. Surgical removal of the lens material is generally indicated shortly after the injury in an effort to preserve vision. Leaking of lens proteins through an intact lens capsule may result in a lympho-plasmacytic anterior uveitis. This is most commonly associated with the presence of a hypermature cataract. The presence of lens-induced uveitis prior to cataract surgery significantly reduces the success rate of cataract surgery. Small amounts of circulating lens proteins maintain a normal T-cell tolerance for lens proteins. Lens-induced uveitis develops when a breakdown occurs of this normal T-cell tolerance. Immune complexes play an important role in the tissue damage associated with the ensuing inflammation. Other factors associated with the tissue damage include hydroxyl radicals, nitroxide radicals, and hydrogen peroxide and arachidonic acid metabolites. Treatment consists of topical and systemic anti-inflammatory medications, mydriatic agents, and glaucoma medications when indicated. Experimental pharmacological agents include dual cyclooxygenase/lipoxygenase inhibitors, interleukin-1 blockers, antioxidants and hydroxyl radical scavengers.     

Uveodermatologic syndrome in a Brazilian Fila dog

A 5-year-old Brazilian Fila dog was presented with a history of vision loss, alopecia, and generalized depigmentation of the skin and hair. Clinical examination confirmed generalized depigmentation and pyodermitis. On ophthalmic examination there was depigmentation at the eyelid mucocutaneous junction, associated with anterior uveitis, and bilateral posterior synechia at 360 degrees. Both the complete blood count and skin scraping were normal. Skin biopsy showed histiocytary lichenoid interface dermatitis with an absence of pigment within the queratinocytes, and a moderate lymphomononuclear infiltrate and predominance of histiocytes in the papilar derma suggestive of uveodermatologic syndrome. Clinical management consisted of oral and topical administration of prednisone, associated with 1% indometacine eye drops. Methylprednisone was also used twice via the subconjunctival route, at an interval of 15 days. To prevent the development of secondary glaucoma due to posterior synechiae, dorzolamide and timolol eye drops were indicated. Both dermatologic and ophthalmic signs showed good improvement, vision was preserved, and some repigmentation of the skin and hair occurred.     

Ultrasound biomicroscopy of the feline anterior segment

Ultrasound biomicroscopy was performed on enucleated feline globes as a model for use in vivo. Quantitative measurements were obtained from the anterior segment using a 50-MHz transducer. Mean values from 26 feline globes were axial corneal thickness, 0.74 mm; anterior chamber depth, 4.20 mm; distance from the first ciliary process to the limbus, 3.17 mm; angle recess, 0.38 mm; angle opening distance, 1.05 mm; iris base width 0.38 mm; iris middle width 0.52 mm; iris tip width 0.13 mm, and iris-lens overlap, 0.69 mm. Distinctive features of the feline anterior segment include a relatively wide iridocorneal angle and deep anterior chamber.     

Immunohistochemical identification of Encephalitozoon cuniculi in phacoclastic uveitis in four rabbits

PURPOSE: Encephalitozoon cuniculi is a microsporidium with a wide range of mammalian hosts. In rabbits it can be responsible for cataract and lens-induced uveitis (LIU). The aim of this study was to provide specific immunohistochemical demonstration and localization of E. cuniculi within the eye, in rabbits with LIU. MATERIAL AND METHODS: Four rabbits were presented with a white mass in the eye and iris discoloration. Complete ophthalmic examinations were performed and a presumptive diagnosis of LIU was made in all cases. Initial therapy with a topical steroid, atropine and systemic enrofloxacin was instituted while serologic (IFA or ICA tests) and cytologic lab results were pending. The final outcome in all cases was enucleation. Routine histology and immunohistochemistry (ABC method) with an antiserum anti-Encephalitozoon cuniculi were performed. RESULTS: Indirect immunofluorescence performed on one rabbit serum expressed a titer of 1 : 32; carbon immunoassay on the serum of the other three rabbits expressed a titer of 1 : 5120 in one, and a titer of 1 : 2560 in the other two cases. Histologically, an intraocular, locally extensive pyogranulomatous infiltration that partially filled the posterior chamber, encasing a wide anterior lens capsule break, was detected in all cases. Immunohistochemically, spores reacting with anti-Encephalitozoon cuniculi antiserum were present in all specimens, occasionally within macrophages and lens epithelial cells. CONCLUSION: Detection of E. cuniculi in rabbits with phacoclastic uveitis has been investigated in the past with different methods. Based on our results, we suggest that immunohistochemistry should be regarded as a useful tool both for specific demonstration of E. cuniculi and for its localization within tissues.