Comparative Histological Study of the Small Intestine in Lizards (Reptilia)

A light and electron microscopica study of the small intestine of four species of lizard was conducted. The organization of the small intestine is described and comparisons are made between the species examined.     

Pathology of experimental CV777 coronavirus enteritis in piglets. I. Histological and histochemical study

Sixteen cesarean-derived colostrum-deprived piglets were infected oronasally with CV777 coronavirus on the second or third day of life. Two uninfected piglets were controls. They were killed at 96 and 120 hours after birth. After an incubation period of 22 to 36 hours, all principals showed severe diarrhea. The principals were killed between 12 and 120 hours after infection. Exfoliation of enterocytes were seen first in the piglet killed 24 hours after infection (two hours after the diarrhea began). From that time on, shortening and fusion of villi was present in all small intestinal parts. Affected cells showed vacuolation. The histochemical study showed that infected piglets had decreased activity of all four enzymes studied. The light microscope showed no lesions in the absorptive colonic epithelium. The significance of the lesions in relation to intestinal dysfunction is discussed, and lesions are compared to those of transmissible gastroenteritis and porcine rotavirus infection.     

鸡食管扁桃体的组织学和免疫组织化学研究

本研究通过组织学和免疫组织化学方法,观察鸡新型肠相关性淋巴组织-食管扁桃体的组织结构特征。并研究其中T淋巴细胞及其亚群和抗体生成细胞的定位分布。研究发现,食管扁桃体的粘膜形成数目和结构与食管一致的皱襞,粘膜固有层中分布大量的淋巴组织,并存在于前胃腺;在隐窝固有层中,抗体生成细胞以IgM^＋和IgA^＋细胞为主,并主要分布在生发中心中,而CD3^＋、CD4^＋和CD8^＋T淋巴细胞也有大量分布,主要存在于生发中心周围的滤泡间区域;在皱襞固有层中,各种淋巴细胞都分布在上皮下固有层中,数量明显少于隐窝固有层中的相应阳性细胞,抗体生成细胞以IgA^＋细胞为主,T淋巴细胞则以CD3和CD4为主。研究表明：食管扁桃体位置特殊,将接触到大量的外界未消化抗原,并且它具有参与粘膜免疫的组织基础和细胞基础,此研究结果对食物过敏、免疫耐受和肠道感染的研究具有重要意义。     

Histological study of granulated metrial gland (GMG) cells in beige (DA-bg/bg) rats

To clarify the roles of granulated metrial gland (GMG) cells for successful pregnancy in rats, GMG cells in beige rats (genotype: DA-bg/bg), whose NK cells show lysosomal dysfunction because of abnormalities in cytoplasmic granules, were examined in mid- and late-pregnancy by light and electron microscopies. The GMG cells of beige rats were significantly less in number than those of the two controls (genotypes: DA-bg/+ and DA-+/+) in mid- and late-pregnancy, and this accompanied a low reproductive performance in the beige rats. The size of intracellular granules in the GMG cells of the beige rats was larger than for the two controls on each corresponding day of pregnancy. These results suggest that the activity of rat GMG cells and peripheral NK cells might be influenced by the beige gene, which is involved in reproductive performance.     

Comparative study of diagnostic testing for feline leukemia virus infection.

Results of commercially available diagnostic test kits and commercial laboratory test results were compared for ability to detect FeLV antigen. Results of the immunofluorescent antibody (IFA) test were compared with test kit ELISA results and with results of a system in which samples were applied to an absorbent material, dried, sent to a laboratory, eluted, and assayed by a plate ELISA. Test kits were generally highly sensitive and specific, compared with the IFA test performed at a commercial laboratory. Feline heterophile antibody, specific for mouse immunoglobulin, was detected in approximately 0.14 to 0.57% of the cat population. Test kits B, E, and D contain reagents that correct for antimouse antibodies. During 1989 and 1990, 2,229 feline serum samples were tested for FeLV antigen (gsa p27); positive ELISA results were obtained for 204 (9%) of the samples. Results for 32 (1.4%) samples were interpreted as equivocal (color development slightly exceeded that of the negative control, but was much less than that of the positive control). Collectively, the data indicate that when testing serum or saliva, a negative test result may be a good predictor that a cat is not infected. In populations of cats in which FeLV prevalence is low, a positive test result may not be reliable and thus, a confirmatory test should be performed.     

Cataract surgery. Current approaches

Cataract surgery in the dog can be a highly successful and rewarding technique for restoring vision to the cataract patient. Coexisting ocular conditions can complicate cataract surgery or be a contraindication for lens removal; these include KCS, uveitis, glaucoma, lens subluxation, and retinal disease. Techniques for cataract surgery include intracapsular cataract extraction, extracapsular cataract extraction, and phacofragmentation, both extracapsular and endocapsular (intercapsular). Phacofragmentation is probably the most successful technique in the dog at this time. Postoperative complications include uveitis, hyphema, glaucoma, capsular opacities, corneal endothelial damage, and retinal detachments. Newer methods of dealing with these problems include the use of viscoelastic materials and IOL implants intraoperatively and the use of the Nd:YAG laser for posterior capsulotomies postoperatively.     

Sacroiliac Joint of the Horse 3. Histological appearance

To establish a baseline for the histological appearance of the sacroiliac joint of the horse, joint specimens were collected from 41 horses from late fetal life to the age of 14 years. Sagittal sections from the joints were radiographed and sectioned for histological examination.
There was a striking difference in structure between the sacral and iliac articular cartilages, the former being hyaline and the latter predominantly fibrous. Degenerative changes were seen even in young horses and were more markec on the iliac side. The degeneration of the articular cartilage showed a progressive, age-related pattern.     

桑树不同倍数体间形态学与组织学差异的比较研究

对 2倍体、3倍体和 4倍体桑树的形态学和组织学差异进行了研究 ,测定了不同倍数性桑树的单条长度、株条长度、单叶重、单叶面积和气孔的叶绿体数。结果表明 ,所有这些数量性状在不同倍数性间都存在统计学上的显著差异。单条长与株条长度为 3x >2x >4x,单叶重 ,叶面积和叶绿体数为 4x >3x >2x。此特征可以作为多倍体育种程序中初始阶段鉴别与筛选不同倍数体的辅助指标。研究还表明 ,3倍体有着优良的经济性状 ,由两种杂交组合培育的三倍体中 ,平均单条长 2x♀× 4x 显著长于 4x♀× 2x ;从 2倍体杂种实生苗诱导的 4倍体比 2倍体无性系诱导的 4倍体有更好的经济性状。     

Histological study of the hypertrophic placentas and open eyelids observed in cloned fetuses

Mice cloned from somatic or ES cells showed signs of phenotypically various abnormalities. These abnormalities are now considered to result from aberrant gene expressions by epigenetic reprogramming errors but it is still unclear when these abnormalities occur and what histological changes occur during the gestation period. To address these issues, we histologically examined the hypertrophic placentas and open eyelids at 12.5, 17.5 and 19.5 days of the gestation period in ES-derived cloned mice that we have previously reported. In the placentas, the histology revealed that the hypertrophy had already occurred at 12.5 dpc and that the main change was the proliferation of trophoblast cells in the labyrinth layer. In the fetuses and placentas at 17.5 and 19.5 dpc, extensive proliferation of spongiotrophoblast and glycogen cells in the spongiotrophoblast layer and enlarged trophoblast giant cells were observed. Open eyelids in cloned mice were observed from 17.5 dpc, whereas the eyelids of the control mice had already been closed. The histology showed the malformation of eyelids where the formation of the stratum corneum and stratum granulosum in the epidermis was insufficient. Based on the histology described here, further comparative studies of the gene expression and histology of abnormalities seen in cloned mice and in gene-targeted and spontaneously mutated mice with similar phenotypic abnormalities could help illuminate these abnormalities and could contribute to the development of somatic cloning technology.     

Histological and immunohistochemical evaluation of canine chronic superficial keratitis.

Chronic superficial keratitis (CSK) is an inflammatory disease of the canine cornea, characterised by infiltration of leucocytes into the anterior corneal stroma. The present study describes a quantitative histomorphometric analysis of the cell types infiltrating the corneal stroma in this disease. Infiltrating cells were quantified in samples taken at superficial keratectomy and processed for routine histology. Further characterisation of lymphocyte phenotypes was achieved by immunohistochemistry performed using a panel of monoclonal antibodies recognising canine lymphocyte CD antigens. Lymphocytes expressing the CD4 antigen were found to be the predominant infiltrating cell types in the CSK lesion. A significantly smaller number of lymphocytes expressed the CD8 antigen. The CD4/CD8 ratio was consistently above 2 and rose to above 4 at the advancing border of the lesion. A proportion of lymphocytes were shown by immunohistochemistry to contain gamma interferon. This study forms a basis for work further evaluating the cytological events central to the development of this spontaneous potentially auto-immune corneal disease.     

Comparative study of cytotoxicity of Aeromonas spp. on four different cell lines

In vitro cytotoxicity is an important virulence property of motile mesophilic Aeromonas species. Cell-free supernatant prepared from 55 Aeromonas isolates including one A. hydrophila type strain (MTCC 646) were examined for their cytotoxic potential on four different cell lines (Vero, BHK-21, MDBK, B 95a). Results of the study revealed cytotoxic potential in 92.72% of the isolates. Analysis of data exposed significant variation among isolates in respect of their cytotoxicity. Vero cells proved to be most sensitive to aeromonal toxins and B 95a cells showed significantly (P<0.01) lower response compared to other cell lines. Sensitivities of BHK-21 and MDBK cell lines were in between Vero and B 95a.     

Nontraditional approaches to pain management.

The word nontraditional in the context of this article implies those modalities not normally taught in veterinary medical schools. This word has the same definition of Complementary and Alternative Medicine (CAM) as put forth by the Harvard medical school. CAM is a field of medicine that has enjoyed a recent increase in popularity in both human and equine medicine, particularly in regard to pain management. Some of the more recognized modalities include acupuncture, herbalism, and homeopathy. A brief discussion regarding the theory, scientific evidence and use of these therapies in the treatment of pain will be discussed.     

Fish oil-induced yellow fat disease in rats. I. Histological changes

Yellow fat disease was induced in young rats given a vitamin E-deficient diet supplemented with 15% fish oil. The changes in adipose tissue of this oil-induced disorder were different from those of natural yellow fat disease in horse, pig and mink. In the natural disease all fat depots had the early stage of yellow fat disease with interstitial lipofuscin-laden macrophages exclusively. In the rat, however, this change was seen only in the subcutaneous fat depot. Moreover, affected adipose tissue of animals with natural disease had extensive fibrosis, but in the rat fibrosis was always absent. Rats with fish oil-induced yellow fat disease had degenerative changes in various fat depots that occurred at various times but in the horse, pig and mink fat depots were affected simultaneously. Lipofuscin accumulated in the reticuloendothelial system in rats. Accumulation in spleen and liver was dependent on vitamin E deficiency, but only the accumulation in the Kupffer cells was correlated with yellow fat disease. Lipofuscin accumulation in the mesenteric lymph node did not depend on vitamin E deficiency.     

Histological differences in full-thickness vs. lamellar corneal pig-to-rabbit xenotransplantation

To evaluate the differences in graft survival and histopathological characteristics between full-thickness and lamellar orthotopic corneal xenotransplantation in a pig-to-rabbit model, we orthotopically transplanted a full-thickness or the anterior half of a pig's cornea onto the OD of 16 rabbits. As a result, the median survival were 16.83 and 29.07 days for the full-thickness and lamellar xenografts, respectively ( P  = 0.0005). Histologically, the full-thickness corneal xenografts had massive infiltration by eosinophils, whereas the lamellar xenografts showed predominantly mononuclear infiltrates ( P  < 0.05). Given these preliminary findings, lamellar corneal xenografts in rabbits survived longer than the full-thickness xenografts and each type of graft demonstrated different rejection mechanisms.