Modulation of proteolytic activity associated with persistent corneal ulcers in dogs

Canines affected with corneal lesions demonstrate increased proteolytic activity at the affected site. Canines that develop persistent corneal ulcers and maintain elevated levels of proteolytic activity respond to protease inhibitor therapy with polysulpated glycosaminoglycan, PSGAG. In this study, the proteolytic activity expressed in lacrimal fluid of canines was evaluated as normal (1.15 U mL⁻¹) or healed (1.19 U mL⁻¹). Six of the 26 dogs affected with persistent corneal ulcers, however, had a protease level consistent with the unaffected control animals. These dogs did not appear to respond to PSGAG therapy. Two pathophysiologies for persistent corneal ulcers are indicated. Identifying which mode is active could help determine the therapeutic treatment needed.     

不同时期施铁对水稻根表铁胶膜中铁镉含量及根系含镉量的影响

采用镉污染土壤-河砂-营养液联合培养的方法,研究了不同时期施铁对水稻根表铁胶膜中铁、镉含量的影响。选择水稻的分蘖、拔节、孕穗和灌浆4个时期,进行分期和各生育时期都施加铁的处理,在每个处理时期,设4个亚铁(Fe2 )水平分别为0、30、50和70mg·L-1,研究根表施铁浓度与水稻根表铁胶膜数量和吸附镉量之间的关系。结果表明,生长过程中取样测定的水稻根表铁胶膜铁含量,除个别处理外,都表现为施加铁的根表铁胶膜铁含量高于未施加铁的根表铁胶膜铁含量,尤其是孕穗期,随着施铁量的增加根表铁胶膜铁含量增加。成熟时测定,灌浆期处理的水稻根表铁胶膜铁的含量变化比较大,分蘖期和拔节期变化比较小。各生育时期都处理的根表铁胶膜铁含量以施加Fe2 50mg·L-1最高。水稻根系的含镉量,生长期间测定的结果是前期处理高于后期处理,而收获时测定的结果是前期和后期处理的根系含镉量趋于一致。各生育期都处理的根系含镉量以施加Fe2 50mg·L-1最高,与根表铁胶膜中含铁量相符。     

Effect of heterogenic corneal stroma transplantation on peripheral T cells of rats

AIM: To Compare immunogenicity of three kinds of heterogenic corneal stroma. METHODS: 36 SD rats were randomized into 4 groups, each group consisting of 9 rats. Group 1 was control group. Three kinds of heterogenic corneal stroma: porcine, rabbit and chicken corneal stroma were heterotopically transplanted to subcutaneous layer of 27 (group 2-4) SD rats, respectively. The expression of CD4⁺, CD8⁺, CD25⁺, CD71⁺ on peripheral T cells was identified and analyzed by dual fluorescence flow cytometry at 7, 14, 28 days after operation. RESULTS: Compared with control group, the expression of CD4⁺, CD8⁺, CD25⁺, CD71⁺ was no significant change in porcine corneal stroma group(P＞0.05), the expression of CD4⁺ was increased in rabbit corneal stroma (P＜0.05), CD4⁺, CD4⁺ CD71⁺ markedly higher in the chicken corneal stroma (P＜0.01) at 7 days after operation. CONCLUSION: The immunogenicity of porcine stroma is the lowest in three kinds of heterogenic corneal stroma (chicken, rabbit and porcine).     

Decellularized porcine corneal posterior lamellae as carrier matrix for cultivating human umbilical vein endothelial cells in vitro

AIM：To investigate the feasibility of corneal posterior lamellar reconstruction with human umbilical vein endothelial cells (HUVECs) and porcine cornea acellular matrix in vitro, and to observe the physiological function of the transplantation in vivo. METHODS：HUVECs were isolated, cultured, and labeled with fluorescent dye CM-DiI. Porcine corneas were treated with 100% glycerinum, cut to a thinner structure step by step, and dried on the super-clean bench. Transmission electron microscope were used to observe the histological changes of the porcine cornea acellular matrix. Labeled HUVECs were seeded onto the porcine cornea acellular matrix, and examined by scanning electron microscopy. When the HUVECs and Descemets membrane fusion formed a monolayer, the corneal transplantation in rabbits was performed. Twenty-four New Zealand white rabbits were randomly divided into experimental group and control group (n=12 each), and their left eyes served as recipients. RESULTS：Cultured HUVECs exhibited polygonal shape. More than 90% HUVECs were labeled with CM-DiI and the cell membrane was positive with red fluorescence, which was detectable at least up to 3 generations. The histological examination indicated that porcine cornea cells were clearly extracted, and the collagen fibers were well arranged. A continuous monolayer of HUVECs on the porcine cornea acellular matrix was observed under scanning electron microscopy. The reconstructed corneal posterior lamellae were similar to the normal cornea. The observation of transplantation showed that the cornea in experimental group was substantially transparent. However, that in control group was oedematous and adiaphanous. CONCLUSION：Corneal posterior lamellae can be reconstructed in vitro by cultivating HUVECs on porcine cornea acellular matrix. After xenogeneic transplantation, the graft survives in vivo and expresses normal corneal endothelial cell biological functions. Deep lamellar corneal endothelial transplantation is an effective keratoplasty.     

Antibody Testing Against Canine Coronavirus by Immunoperoxidase Plaque Staining

The application of the immunoperoxidase (IP) plaque staining procedure (IP test) to the diagnosis of canine coronavirus (CCV) infection was investigated. The IP test did not react with sera from either 15 specific pathogen-free (SPF) dogs or 7 SPF dogs immunized with a multivalent vaccine, including canine parvovirus type 2, canine distemper virus, canine adenovirus type 2, and canine parainfluenza virus. To compare the IP test with the neutralizing test (NT), sera from 240 healthy dogs and from 3 experimentally CCV-infected dogs were examined. All 60 sera positive for NT antibody were positive for IP antibody, and all 180 sera negative for NT antibody were negative for IP antibody in the healthy dogs. The IP titres showed similar changes with time after CCV inoculation to those of the NT titres in the experimentally infected dogs. These findings indicate that the IP test specifically detected anti-CCV antibodies. When the IP test and NT were compared in dogs with diarrhoeic signs. 2.1% of 48 sera and 20.3% of 74 sera, which were all negative for NT antibody, were positive for IP antibody in the dogs of under one year of age and at least one year of age, respectively. The difference between the IP and NT titres (log₁₀ [reciprocal of IP titre] – log₁₀ [reciprocal of NT titre]) for the diarrhoeic dogs of under one year of age (2.350±0.931) was significantly larger than that for the healthy dogs (0.982±0.447) (p<0.0001), the NT titre being negative or very low, despite a high IP titre in many diarrhoeic dogs. Hence, the IP test is more able to detect anti-CCV antibodies, especially in dogs showing clinical signs. The IP-positivity rate was significantly higher in the diarrhoeic dogs of under one year of age (48.7%) than in the healthy dogs (25.0%) (² = 19.844, p<0.0001), suggesting that CCV may contribute to diarrhoea in many juvenile dogs.     

Corneal innervation in mesocephalic and brachycephalic dogs and cats: assessment using in vivo confocal microscopy

Objective To determine the density of the canine and feline corneal neural network in healthy dogs and cats using in vivo confocal microscopy (IVCM). Animals examined A total of 16 adult dogs (9 Mesocephalic breeds, 7 Brachycephalic breeds) and 15 cats (9 Domestic Short-haired cats (DSH), 6 Persian cats) underwent IVCM. Procedure Animals were examined with a confocal corneal microscope (HRTII/RCM; Heidelberg Retina Tomograph II/Rostock Cornea Module^®, Heidelberg Engineering, Dossenheim, Germany). The investigations focused on the distribution of the corneal nerves and quantification of central subepithelial and subbasal nerve plexus. Results The corneal stromal nerve trunks, subepithelial and subbasal nerve plexus were observed. The nerve fiber density (NFD) quantified in nerve fiber length in mesocephalic dogs were 12.39 ± 5.25 mm/mm² in the subepithelial nerve plexus and 14.87 ± 3.08 mm/mm² in the subbasal nerve plexus. The NFD of the subepithelial nerve plexus in DSH cats was 15.49 ± 2.7 and 18.4 ± 3.84 mm/mm² in the subbasal nerve plexus. The subbasal NFD of DSH cats was significantly higher than in mesocephalic dogs (P = 0.037). The subepithelial NFD in brachycephalic dogs, and Persian cats were 10.34 ± 4.71 and 9.50 ± 2.3 mm/mm², respectively. The subbasal NFD measured 11.80 ± 3.73 mm/mm² in brachycephalic dogs, and 12.28 ± 4.3 mm/mm² NFD in Persian cats, respectively. The subepithelial and subbasal NFD in Persian cats were significantly lower than in DSH cats (P = 0.028, respectively, P = 0.031), in contrast to brachycephalic vs. mesocephalic dogs. Conclusion The noninvasive IVCM accurately detects corneal innervation and provides a reliable quantification of central corneal nerves.     

46例穿透性角膜移植术的改进

探讨穿透性角膜移植术全过程中改善移植预后的方法。方法：在４６例穿透性角膜移植过程中,注意手术过程中的各个环节,包括：新鲜或保存良好的供体角膜;手术过程中采用多种方法保护角膜内皮细胞;前取供体植片时前房注入１０ｇ／Ｌ玻璃酸钠,内皮侧冲切制作值入,将植入预预置缝合６针固定于植床再用１０ｇ／Ｌ玻璃酰内及眼用平衡盐溶液形成前房;适时拆线防止排斥反应的发生;及早治疗移植排斥反应。结果：术后随访３－３６个月     

焉耆盆地44a来景观格局变化分析

[目的]揭示焉耆盆地 1964～2007 a 景观变化规律,为合理开发利用绿洲水土资源和生态安全评价提供依据.[方法]根据焉耆盆地1964～2007 a 5期遥感影像解译数据,进行景观变化分析.[结果]耕地从1964 a占整个研究区面积的8.96;到2007 a的44.69;,成为焉耆盆地最主要的景观; 1964～2007 a,草地面积减少了94.51;,主要转变为耕地;水域面积减小约1/3,遥感影像上表现出河面、湖面的萎缩;林地景观曾一度消失,近7 a在退耕还林政策推动下再次出现;湿地景观相对稳定.研究期内,城乡、工矿建筑用地面积占整个研究区面积比例从0.04;上升到2.90;,但仍然属于非优势景观;未利用土地位于其他景观外围,2000～2007 a未利用地在博斯腾湖大湖东北角处有了一定的增加.[结论]近半个世纪以来,随着人类对焉耆盆地自然景观干扰强度的增加,研究区内景观多样性水平降低,异质化程度降低,土地利用向单一化方向发展,土地开发已达极限,生态安全面临威胁.     

新城疫Ⅰ系病毒不同空斑克隆株生物学测定试验

新城疫Ⅰ系种毒稀释接种鸡胚成纤维细胞(CEF)单层后覆盖含中性红的1.6%营养琼脂糖,37℃培养至72h,分别挑取大(φ2～3mm)、中(φ1～2mm)、小(φ1mm)三种空斑,反复冻融后收获病毒,同样方法空斑克隆三代后,通过SPF鸡胚继代增殖,对收获物进行ELD50、MDT、ICPI测定。结果表明,三种空斑克隆株继代培养物中,中斑毒力最强,大斑次之,小斑最弱;大斑克隆株增殖力最强,中斑次之,小斑最差。     

Morphological analysis of cell distribution and network structure via gap junctions in swine corneal stroma

Because of corneal transplantation limitations, there is a need for cornea-specific regenerative medicine. The development of such regenerative medicine has been delayed because of the complex and unique structure of the corneal stroma. Few studies have explored the corneal stroma cell distribution and cell types in vivo. This study investigated regional differences in morphological characteristics and distributions of corneal keratocytes and immunocompetent cells in the corneal stroma to clarify their functions and structural characteristics. The porcine eyeballs were subjected to light microscopy, transmission electron microscopy, scanning electron microscopy, and immunofluorescence staining analyses. Corneal cells were primarily located in the limbus, rather than the center of the cornea; the long keratocyte diameter was largest on the epithelial side of the corneal limbus, while the short diameter was largest on the endothelial side of the central cornea. Moreover, there were significantly more corneal cells on the epithelial side than on the endothelial side in both the central and limbus areas. Gap junctions between cells in the corneal stroma were present on the surfaces of cytoplasmic processes. Many cytoplasmic processes were scattered throughout the corneal stroma; they were connected both vertically and horizontally, forming an intercellular network. Additionally, immunocompetent cells on the epithelial side suggested to participate in this network via gap junctions. The morphology of keratocytes and immunocompetent cells on the epithelial side suggests that they play important roles in corneal homeostasis.