Fine Structure of the Feline Tapetum lucidum

The morphology of the tapetum lucidum of the domestic cat (Felis catus) was studied by electron microscopy. The tapetum is a tapetum cellulosum, localized in the choroid of the dorsal fundus. The cells comprising this structure are described.     

Fine Structure and Peroxidase Activity of the Bovine Mandibular Gland Cells

The acini of the bovine mandibular gland consist of mucous and demilunar seromucous cells. The mucous cells contain electron-lucid mucigen droplets or mucoid masses, only rarely delimited by membranes. The cisternae of the RER communicate freely. Mitochondria are scarce. The seromucous demilunar cells contain considerably more granules, and perigranular membranes are far more common. Many granules have characteristic alternating electron opaque and less electron dense areas. The prominent RER appears to be associated with a peculiar labyrinth of interconnecting tubules. Mitochondria are numerous. Numerous myoepithelial cells are observed. The cuboidal cells of the intercalated ducts lack signs of secretory activity. The columnar cells of the striated ducts have extensive infoldings of the basal plasma membrane, associated with mitochondria. The cell apex contains many granulated vesicles. Endogenous lactoperoxidase activity could be demonstrated only in the demilunar cells, within the secretory granules, the RER, including the perinuclear cisternae, as well as the labyrinth mentioned above. A positive reaction could be observed over acinar lumina and in intercellular canaliculi. The possible role of peroxidase as a component of a bactericidal system of the bovine saliva is discussed.     

The Fine Structure of Mast Cells in the Normal Bovine Mammary Gland

The mast cells from the mammary gland of the cow greatly resemble the mast cells of man and small laboratory animals. However, certain ultrastructural differences are found in the mast cell granules. These granules are divided into four different types according to their morphology. All contain a granular material of varying fineness, bounded by a membrane. In addition a fibrous or crystalline part is found in some granules, while in others a large light vacuole can be seen. All the granules are surrounded by a unit membrane.     

Ultrastructural Observations on the Tapetum lucidum fibrosum

The ultrastructural comparison made between the tapetum cellulosum of the cat and the tapetum fibrosum of the sheep has shown that the rods and the collagen fibrils have the same diameters and the same spatial arrangement.     

牛咽部组织结构的显微观察

[目的]运用组织学方法对3.5岁龄公牛咽部组织结构进行了观察与分析,以研究牛咽部不同部位显微结构。[方法]使用石蜡切片及HE和PAS染色在光学显微镜下观察牛咽部不同部位组织形态及细胞类型。[结论]牛鼻咽部黏膜层属于假复层柱状纤毛上皮结构,其间有大量的杯状细胞,没有角质层;喉咽部和口咽部属于复层扁平上皮结构,其间没有杯状细胞,有角质层。     

成年母鸡松果腺组织结构的研究

用透射与扫描电镜和荧光显微镜对25只成年母鸡的松果腺进行了系统观察。松果腺主要由松果体细胞组成,其间夹杂有少量胶质细胞。松果体细胞的核呈圆形或椭圆形,而胶质细胞的核多呈不规则形。松果体细胞具有突起,线粒体丰富,高尔基复合体发达,胞质中散布有核糖体,并见有粗面和滑面内质网、微管、溶酶体、脂滴以及少量致密核芯小体和板层小体。胶质细胞的结构特征为胞质中含有微丝。毛细血管内皮不含窗孔。本研究结果表明,鸡松果体细胞具有内分泌细胞的结构特征,因而认为鸡的松果腺是一个内分泌腺。     

The Fine Structure of the Fundic Stomach Epithelium of the Western Newt

The effects of varying intensities of histamine stimulation on cells of the western newt fundic stomach epithelium have been studied. Oxyntic, mucous neck and surface mucous cells all secrete. In the oxyntic cell, the main effects are a movement of zymogen granules toward the apex, the discharge of their contents into the lumen and, eventually, their disappearance from the cytoplasm. Additionally, the tubular membrane elements (tubulo- vesicles) fuse with the apical plasma membrane with a corresponding reduction in their numbers and an increase in microvilli, which eventually are so numerous as to virtually occlude the lumina of gastric glands. Total histamine stimulation results in apparent damage to the oxyntic cells. Mucous neck and surface mucous cells release their mucigen droplets by exocytosis and are grossly changed in appearance also.     

Expression and Structure Function Prediction of Bovine Pregnancy-associated Glycoprotein 2

In order to obtain bovine pregnancy-associated glycoprotein 2 (BoPAG2) with high expression and purification and good antigenicity,the structure and function of the protein were analyzed by bioinformatics prediction.The BoPAG2 gene of Holstein dairy cow was amplified by PCR,and the gene was ligated into the expression vector pET-28a,transformed into E.coli (BL21) to induce expression and purification.SDS-PAGE and Western blotting were used to verify and detect the size and immunological characteristics of the protein.The glycosylation modification,B-cell epitope,hydrophilicity,signal peptide,secondary structure and 3D model,conservative domain and protein interaction of BoPAG2 protein were predicted and analyzed by bioinformatics.The results showed that the BoPAG2 gene was successfully cloned,and the corresponding protein was expressed and purified by induction.The size of the BoPAG2 protein was consistent with the expected results by SDS-PAGE and Western blotting.The results of bioinformatics prediction analysis showed that five sites of BoPAG2 protein occurred glycosylation modification,Asp⁵¹,Asp⁷¹,Asp¹¹⁴,Asp²⁵² and Asp³⁴³,respectively.The protein contained 15 B-cell epitopes and a signal peptide sequence consisting of 15 amino acids in the N terminal.The 3D model of the BoPAG2 protein was successfully established.The protein contained 4 superfamily domains.The results of protein interaction analysis showed that there were 7 proteins that interact with BoPAG2.The protein might be involved in digestion and absorption.Other processes in the maternal regulatory function during pregnancy.In summary,the BoPAG2 protein was successfully expressed and purified in this experiment.The bioinformatics prediction analysis of the structure and function of BoPAG2 protein provided a theoretical basis for the preparation and function research of BoPAG2 protein antibody.     

奶牛妊娠相关糖蛋白2的表达及结构功能预测分析

为了获得高效表达纯化并且抗原性较好的牛妊娠相关糖蛋白2（bovine pregnancy-associated glycoprotein 2,BoPAG2）,对该蛋白的结构与功能进行生物信息学预测分析。通过PCR扩增荷斯坦奶牛BoPAG2基因,并将该基因连接至表达载体pET-28a,转化至大肠杆菌（BL21）中诱导表达并纯化,通过SDS-PAGE和Western blotting验证与检测该蛋白的大小和免疫学特性,通过生物信息学对BoPAG2蛋白的糖基化修饰、B细胞抗原表位、亲水性、信号肽,蛋白二级结构和3D模型、保守结构域以及蛋白互作进行预测分析。结果表明,本研究成功克隆出BoPAG2基因,通过诱导表达并纯化相应蛋白,通过SDS-PAGE和Western blotting验证BoPAG2蛋白的大小与预期结果相符,通过生物信息学预测分析结果显示,BoPAG2蛋白有5个位点发生糖基化修饰,分别为Asp⁵¹、Asp⁷¹、Asp¹¹⁴、Asp²⁵²和Asp³⁴³,该蛋白含有15个B细胞抗原表位,在N端含有15个氨基酸组成的信号肽序列,二级结构主要以无规则卷曲和延伸链为主,并且成功建立了BoPAG2蛋白的3D模型,该蛋白含有4个超家族结构域,蛋白互作分析结果显示,与BoPAG2互作的蛋白有7个,该蛋白可能参与了消化和吸收,以及母体在妊娠期的调节功能等过程。综上所述,本试验成功表达并纯化获得了BoPAG2蛋白。通过对BoPAG2蛋白的结构及功能进行生物信息学预测分析,为BoPAG2蛋白抗体的制备以及功能的研究提供了理论基础。     

Infection of the Bovine Udder with Bovine Herpesvirus

Infectious bovine rhinotracheitis — infectious pustular vulvovaginitis (bovine herpesvirus) grown in tissue culture was used as inoculum in trials to infect the lactating bovine udder. Six experiments were undertaken in which one or more quarters were infused with 1 ml. of tissue culture fluids containing 10⁶ to 10⁷ tissue culture infectious doses (TCID) of virus. In four of the experiments the inoculated quarters showed marked evidence of infection in the form of acute inflammation, swelling, reduced milk secretion and profound changes in the physical appearance of the milk. In each case virus was recovered in high titres in the milk from about the second until the tenth to fifteenth days following exposure. Uninfected quarters remained normal in appearance and virus could not be recovered from the milk.

In three of the experiments it was shown that serum and milk antibodies appeared shortly after the disappearance of virus from the milk. One experiment involving two animals showed that about 1000 TCID of virus were required to produce infection. In one experiment a cow having a pre-inoculation serum titre for bovine herpesvirus proved resistant to infection.

The experiments indicate that the bovine udder is readily susceptible to bovine herpesvirus in non-immune animals, and that the virus produces an acute, limited infection leading to a temporary disfunction of the gland. It appears that natural invasion of the udder through the teat canal is not readily accomplished by the virus.

     

Fine Structure of the Choriocapillaris, Bruch''s Membrane and Retinal Epithelium of the Cow

The fine structure of the choriocapillaris, Bruch's membrane and retinal epithelium was investigated in both the tapetal and non-tapetal fundus of the bovine eye. In ail locations the retinal epithelium consists of a single layer of cuboidal cells. The epithelial cells are joined laterally by apically located tight junctions and throughout the retina display numerous basal infoldings and fine apical processes which enclose rod outer segments. All retinal epithelial cells are rich in smooth endoplasmic reticulum and mitochondria and contain phagosomes. Although not as abundant, profiles of rough endoplasmic reticulum and polysomes are also noted in all locations. In non-tapetal areas, melano-somes are numerous whereas over the central tapetum fibrosum they are absent. The absence of melanosomes over a functional tapetum is to be expected. While lysosomes are present throughout the epithelial layer, over the tapetal region they appear to be more numerous. The apparent increase in lysosomal numbers in this location may indicate an enhanced shedding of outer segment material over the tapetum. Although some retinal epithelial cells are modified to accomodate a tapetum lucidum their morphology is basically similar throughout the retina and probably indicates that ail regions of the retinal epithelium are capable of the normal functions of this indispensible retinal layer. The choriocapillaris is heavily fenestrated on the border facing the retina and overlying the tapetum also displays fenestrae on its choroidal edge. Bruch's membrane ( complexus basalis ) is pentalaminate throughout the retina and is slightly thicker in the posterior fundus.     

Fine Structure of the Retinal Photoreceptors of the Domestic Cat (Felis catus)

The morphology of the retinal photoreceptors of the domestic cat (Felis catus) has been investigated by light and electron microscopy. In this species the photoreceptors can be readily differentiated and adequately described by the classical terminology of rods and cones, with rods being the more numerous. Rods are long slender cells with inner and outer segments of much the same diameter. Cones are shorter cells with a conical outer segment that tapers distally and an inner segment which is wider than the outer segment. Both rods and cones are highly polarized and compartmentalized cells and consist of an outer segment, a connecting cilium, an inner segment, a nuclear region and a synaptic process leading to an expanded synaptic ending. Morphological similarities and differences are noted between the rods and cones for the various regions of these cells.     

Fine Structure of the Pecten Oculi of the Red-Tailed Hawk (Buteo jamaicensis)

The pecten oculi of the red-tailed hawk (Buteo jamaicensis) has been examined by light and electron microscopy. In this species the pecten is very large and of the pleated type. It consists of 17-18 accordion folds which are joined apically by a heavily pigmented bridge of tissue which holds the pecten in a fan-like shape, widest at its base. It is situated over the optic nerve head and extends into the vitreous. Within each fold are numerous capillaries, larger supply and drainage vessels and melanocytes. The capillaries are specialized and display extensive microfolds on both the luminal and abluminal borders. The endothelial cell bodies are thin with most organelles present in a paranuclear location. The capillaries are surrounded by thick fibrillar basal laminae which are probably structurally important and which often enclose pericytes. The melanocytes which are most plentiful in the bridge region and peripherally in the pecten, form an incomplete sheath around the capillaries and other blood vessels. These melanocytes are also felt to be fulfilling a structural role within the pecten. The morphology of the pecten of the red-tailed hawk is indicative of a heavy involvement in the transport of materials to the avascular avian retina.     

奶牛血和乳中性粒细胞的形态与功能研究概述

中性粒细胞(PMN)是感染性奶牛乳腺炎的重要防御屏障。文章着重介绍了奶牛PMN在光学显微镜、透射电子显微镜和扫描电子显微镜下的形态特点,并叙述了PMN动力学和各类PMN的生长期、PMN生存期调节与发生奶牛乳腺炎之间的关系,最后提出奶牛PMN的研究方向。     

Fine Structure of the Pecten Oculi in the American Crow (Corvus brachyrhynchos)

The pecten oculi of the American crow (Corvus brachyrhynchos) has been examined by both light and electron microscopy. In this species the pecten is very large and of the pleated type. It consists of 22 - 25 accordion folds that are joined apically by a bridge of tissue which holds the pecten in a fan-like shape widest at its base. Within each fold are numerous capillaries, larger supply and drainage vessels and many melanocytes. The capillaries are extremely specialized for transport functions and display extensive microfolds on both their luminal and abluminal borders. Except for the nuclear region which contains most of the organelles, the endothelial cell bodies are extremely thin. These capillaries are surrounded by thick fibrillar basal laminae which are conjectured to be structurally important. Pericytes are a common feature of these capillaries. The numerous pleomorphic melanocytes interspersed between the capillaries are also felt to be important in structural support of the pecten. The pecten is considered to be comparable to the falciform process of some teleosts, the conus papillaris of reptiles, the supraretinal vessels of amphibians and teleosts and the intraretinal vessels of mammals which are all felt to be alternative methods of bringing nutrients to the inner retina.     

Retinal Photoreceptor Fine Structure in the American Crow (Corvus brachyrhynchos)

The morphology of the light-adapted retinal photoreceptors of the American crow (Corvus brachyrhynchos) has been investigated by light and electron microscopy. They consist of rods, single cones and double (unequal) cones present in a ratio of about 4:3:3 respectively. The rods are stout cells with a long inner segment and an outer segment that reaches to the RPE cell body. In the light-adapted state, the pigment-laden apical processes of the RPE cells surround cell photoreceptor types for most of their length. The rod inner segment displays an ellipsoid of mitochondria, a large hyperboloid of glycogen, much RER, numerous polysomes, Golgi zones and autophagic vacuoles. Single cones show a slightly tapered outer segment, a large and usually heterogeneous oil droplet and an ellipsoid of mitochondria at the apex of the inner segment. Double cones consist of a longer, stouter chief member which displays a more homogeneous oil droplet and a prominent paraboloid of glycogen and a slightly shorter and thinner accessory member with no oil droplet or paraboloid. Both members of the double cone as well as the single cones show a prominent ellipsoid and plentiful polysomes, RER and Golgi zones in the inner segment. Along the length of the contiguous membranes of the two members of the double cone are presumed interreceptor junctions. All cone photoreceptors are relatively small in diameter and hence are tightly packed. Judging by their morphology in the light-adapted state neither rods nor cones are felt to undergo photomechanical movements in this species. Rods and cones (both types) display both invaginated (ribbon) synapses as well as numerous flat (conventional) synaptic sites.     

Retinal Epithelial Fine Structure in the Domestic Cat (Felis catus)

The morphology of the retinal epithelium (RPE) and closely associated choriocapillaris and Bruch's membrane (complexus basalis) has been investigated in the eye of the domestic cat (felis catus) by light and electron microscopy. The RPE consists of a single layer of cuboidal cells joined laterally by apically-located junctional complexes. Basally (sclerally) these cells display numerous infoldings while apically (vitreally) two distinct types of processes enclose photoreceptor outer segments. Internally the large vesicular nucleus is centrally located. Smooth endoplasmic reticulum, mitochondria, polysomes and lysosome-like bodies are abundant. Rough endoplasmic reticulum while present is not plentiful. Over the tapetum lucidum, melanosomes are absent from the RPE cells while in non-tapetal locations melanosomes are large and plentiful. The endothelium of the choriocapillaris is highly fenestrated and these capillaries are deeply indented into the epithelial layer over the tapetum. Bruch's membrane (complexus basalis) is non-tapetal regions is the typical pentalaminate structure noted for most mammals. Over the tapetum however it is reduced to a trilaminate structure and when associated with the indented capillary profiles is further reduced to a single thickened basal lamina.     

Retinal Photoreceptor Fine Structure in the Red-Tailed Hawk (Buteo jamaicensis)

The retinal photoreceptors of the red-tailed hawk (Buteo jamaicensis) consist of rods, single cones and double (unequal) cones present in a ratio of about 2: 11 5. In the light-adapted state, the rods are slender elongated cells with outer segments that reach to the retinal epithelial (RPE) cells. The inner segment displays an ellipsoid of mitochondria, plentiful polysomes, some rough ER and Golgi zones. The rod nucleus is located deep within the outer nuclear layer and the synaptic spherule displays both invaginated (ribbon) and superficial (conventional) synaptic sites. Single cones show a thin tapering outer segment, a large electron lucent oil droplet at the apex of the inner segment and an ellipsoid of mitochondria. Double cones consist of a larger chief member which displays a thin tapering outer segment and an electron dense oil droplet as well as a smaller accessory cone which shows no oil droplet, an ellipsoid and a paraboloid of glycogen. As in the single cone, polysomes, RER and Golgi zones are also noted in the inner segments of both members of the double cone. Near the external limiting membrane the chief and accessory cones show membrane specializations indicative of junctions on their contiguous surfaces. All cone photoreceptors are of a smaller diameter than is normally reported for avian species. Both single and double cones display several invaginated synapses as well as numerous superficial synaptic sites.