Changes in somal growth and dendritic patterns of the retinal ganglion cells in the chicks and chick embryos

Changes in the somal growth and dendritic patterns of retinal ganglion cells (RGCs) were studied in early chick embryos and post-hatching chicks by means of the retrograde axonal transport labeling with DiI. Branching patterns of the dendrites were relatively uniform on E8 (embryonic day 8) and became more complicated on E11. Variety of the branching pattern became plainly abundant after E14. On the other hand, somata of RGCs continued to grow until E14, corresponding the appearance of the central-peripheral gradient of the somal size. After E14, RGCs elaborated on the formation of the dendritic patterns as found in chick retina, and simultaneously the growth of somal sizes almost ceased.     

Dimensional differences among the groups of retinal ganglion cells according to the retinal zones in chicks

The populations of retinal ganglion cell (RGC) groups (Groups I, II, III, IV) were similar each other between the central and intermediate zones, but the population in the peripheral zone were clearly different from those in the central and intermediate zones due to increase of Group III and IV cells and decrease of Group I cells. The dimensions of somal area and dendritic field of Group I cells increased very gradually toward the peripheral zone, but those of other three Groups grew steeply in the peripheral zone. The correlation index between somal area and dendritic field of RGCs showed high coefficient in the central (r=0.73) and intermediate (r=0.77) zones, but lowered clearly in the peripheral zone (r=0.64) due to increase of Group III cells, which showed nonlinear relation between somal area and dendritic field.     

Retrograde tracing with fluorescent microspheres reveals bifurcating projections from central retina to tectum and thalamus in chicks

The goal of this study is to demonstrate the dual-projection pattern of retinal ganglion cells (RGCs) projecting to the tectum and visual thalamus in chick using retrograde fluorescent tracers and also to define the morphological properties of these RGCs with dual projections by intracellular injection of Lucifer Yellow (LY) combined with immunohistochemistry. Thirty-two chicks received double injections of green and red fluorescent microspheres into their thalamus and tectum in the same side. In the central retina, most of the labelled RGCs were tec-RGCs (RGCs projecting to the tectum), a quarter was tha-RGCs (RGCs projecting to the thalamus), and almost all of the tha-RGCs were double-labelled RGCs. An intracellular injection of LY into the double-labelled RGCs showed all six groups of RGCs without specific populations in each group (J. Comp. Neurol., 2004, 469: 360). These dendritic patterns were mostly mono- and bistrata, which extended horizontally in the deeper part of the inner plexiform layer.     

Distribution and cytoarchitecture of sympathetic neurons innervating the pineal gland in chick: a CTB-HRP study

The neurons in bilateral superior cervical ganglia (SCG) innervating the chick pineal gland were labelled by using the technique of retrograde axonal labelling with cholera toxin B subunit linked to horseradish peroxidase (CTB-HRP). To our results, perikarya of these sympathetic neurons distributed from rostral to caudal in the SCG, and mainly localized in the opposite side of the paravertebral trunk. The fibres of these neurons were collected by the cephalic carotid nerve. According to the sizes of somal area and dendritic field, these sympathetic neurons projecting to the pineal gland were classified into four major groups: group I cells (52.4%) with a small somal area (303.5 μm² on average) and narrow dendritic field (3767.8 μm² on average), group II cells (39.0%) with a middle-sized somal area (473.3 μm²) and middle-sized dendritic field (7522.2 μm²), group III cells (6.4%) with a middle-sized somal area (473.4 μm²) and wide dendritic field (13 104.4 μm²), and group IV cells (2.2%) with a large somal area (940.7 μm²) and wide dendritic field (14 553.2 μm²). Of these pineal projecting neurons, most took on a lesser dendritic field. The neurons with small or middle-sized dendritic field from group I and II were about 91.4% of the total neurons labelled with CTB-HRP, and the neurons with wide dendritic field from group III and IV were less with 8.6%.     

Changes in the distribution of labeled retinal ganglion cells after an implant of DiI into the optic nerve in the chick embryos

Changes in the distribution of retinal ganglion cells (RGCs) were studied using the retrograde labeling of DiI in chicks and chick embryos. The small retinal area filled with labeled RGCs was observed in the retinal fundus on E8. The labeled retinal area expanded radially toward the peripheral retina as the retina grew, and finally occupied a whole retina by P1. The temporal retina was labeled more rapidly than in the nasal retina. The observed-increasing rate of the labeled area was corrected with the growing rate of the retina. Consequently, the corrected-increasing rate of the labeled area was estimated to be about 390% between E8 and E11, and 20-50% after E11. This means that spreading speed of the maturated RGCs lowered until 1/10-1/20 after E11.     

Comparative retinal ganglion cell and optic nerve morphology

The optic nerve is divided in four regions: intraocular, intraorbital, intracanalicular, and intracranial. The vertebrate retinal ganglion cells are classified by morphology, physiology and soma size. Species differences and similarities occur with retinal ganglion cells. Alpha retinal ganglion cells have large somata, large dendritic fields, large-diameter axons, and are most dense in the peripheral retina. Beta retinal ganglion cells have smaller diameter somata, smaller dendritic fields, small diameter axons, and predominate in the central retina. Gamma retinal ganglion cells are a heterogenous class of cells and have small diameter axons, and slow axon conduction velocities. The spatial distribution and organization of the retinal ganglion cells extends retinotopically through the nerve fiber layer, optic nerve, optic chiasm, optic tract, lateral geniculate nucleus, and visual cortex. The retinal nerve fiber layer thickness decreases from the optic disk toward the periphery of the retina. The retrobulbar optic nerve axon counts and axon density vary by species, with larger nerves having higher axon counts. Decussation of the optic nerve axons at the optic chiasm varies with 100% decussation in most birds and fish, 65% in cats, 75% in dogs, 80–90% in large animals, and 50% in primates. Centrifugal axons also occur in the optic nerve and may represent a method by which the brain can influence retinal activity.     

Topography of ganglion cells in the retina of the duck (Anas platyrhynchos var. domesticus)

The purpose of this study was to define ganglion cell density, size and topography in the retina of the mallard duck. After killing adult mallard ducks (Anas platyrhynchos var. domesticus), their eyes were removed using pentobarbital (30 mg/kg). The retinas were isolated, whole mount specimens were prepared by staining with 0.1% cresyl violet and then fixing the tissues for study. The retinal ganglion cells were counted, mapped and measured. The mean total number of ganglion cells was estimated at approximately 1.7 × 10⁶ and the retinal area centralis had the highest ganglion cell density with 15 820 cells/mm². The number of ganglion cell bodies was highest in the temporal area, followed by the nasal, dorsal and ventral areas. Ganglion cell size ranged from 56 to 406 μm². A population of small ganglion cells persisted into the central area just above the optic disc and the largest soma area was in the ventral zone of the retina. This localization of ganglion cells suggests that the quality of vision is not equal in all the areas of the duck retina and the central part may have the highest vision quality as a function of the retinal ganglion cells.     

New Morphological Aspects of the Bipolar Cell in the Chick Embryo: The Accessory Prolongation

Using the silver-staining techniques of Golgi Colonnier and Golgi-Stensaas, we have found a new morphological datum in the study and understanding of the structure of the bipolar cell in the chick retina. We describe the existence of a prolongation, possibly dendritic in nature, which sets out from the inner network and separates from its companions following a short path through the outer plexiform layer to terminate freely. It appears for the first time on the 10th day of incubation and always in bipolar cells whose outer branching has its dendritic pattern well-defined. We have named it the accessory prolongation.     

Quantitative analysis of cells in the ganglion cell layer of the chick retina: developmental changes in cell density and cell size

Changes in cell density and size in the ganglion cell layer (GCL) of the retina were studied in chick embryos and post-hatching chicks. The total number of cells in the GCL increased from 3.64 million at embryonic day 8 (E8) to the maximal 7.85 million at E14. After E14, the number of cells decreased to 6.08 million at post-hatching day 1 (P1) and 4.87 million at P8. Cell density in the GCL decreased unevenly according to retinal regions; cell density in the presumptive central area (pCA) of P8-chicks decreased to approximately 45% of that in E8-embryos. Densities of the nasal peripheral retina (NP) and temporal peripheral retina (TP) of P8-chicks decreased to 23 and 18% of E8-embryos, respectively. Differentiation of the central (44,000 cells/mm(2) in pCA) - peripheral (28,000 cells/mm(2) in TP) gradient in cell density was formed by E8. The presumptive dorsal area (pDA) was shaped by E11, but became obscure with age. Although ganglion cell sizes were basically uniform at E8, differentiation occurred with the appearance of larger ganglion cells after E14. Mean size of retinal ganglion cells increased 2.8-fold in the pCA and 3.8-fold in the TP between E8 and P8, accompanying a similar scale of decreases in cell densities.     

Early Morphological Differentiation of the Bipolar Neurons in the Chick Retina A Golgi Analysis

We report a histogenetic study of the bipolar cells of the chick embryo retina between days 5 and 9, using the Golgi technique. On day 8, at the level of the developing outer plexiform layer, small delicate spines appear on the outer processes of the bipolar cells, which represents the commencement of their dendritic ramification. At a later staige in development che detachment of Landolt's club from the outer limiting membrane is observed in some cells The inner ramifications of the bipolar cell, at the inner plexiform layer, appear later than those of the outer process.     

Comparisons of Different Protocols for Vitrifying Mouse Ovarian Tissue

The aim of this study was to detect the effects of different combinations of cryoprotectants with different equilibrium time on the mouse ovarian tissue during vitrification. Ovarian tissue of mice was vitrified‐thawed. Mice (n = 80) were randomly assigned to treatment groups according to different vitrification solutions [I: 20% (v/v) ethylene glycol (EG) + 20% (v/v) Dimethylsulfoxde (DMSO), II: 20% (v/v) EG + 20% (v/v) PROH, III : 20% (v/v) PROH + 20% (v/v) DMSO] and different lengths of equilibrium time (a: 15 min, b: 30 min, c: 45 min). The serum levels of estradiol, the follicular density and the percentage of cells expressing Proliferating‐cell nuclear antigen (PCNA) of grafts in Group IIb were the highest in all these treatment groups. In addition, the serum levels of estradiol, the follicular density and the percentage of cells expressing PCNA of grafts in Group Ib were significantly higher than those in Group Ia and Group Ic, while the serum levels of estradiol, the follicular density and the percentage of cells expressing PCNA of grafts in Group IIIb were significantly higher than those in Group IIIa and Group IIIc. In conclusion, vitrification solution [20% (v/v) EG + 20% (v/v) PROH] with equilibrium time of 30 min is optimal selection for vitrifying mouse ovarian tissue.     

雏鸡投射向外侧膝状体腹侧核的视顶盖细胞形态研究

鸟类的一些视觉信息经由视顶盖Ⅰ层细胞（Ⅰ细胞）传递到外侧膝状体腹侧核（nucleus geniculatus lateralis ventralis,GLv）,用于色觉、瞳孔反射和视觉运动.使用羰花青荧光染料DiI逆向神经标记技术研究了这些投射向GLv核的视顶盖Ⅰ细胞的形态特征.根据标记细胞的胞体和树突野大小及树突分枝特点,雏鸡投射到GLv核的视顶盖Ⅰ细胞可分为“矛状树突Ⅰ细胞”和“叉状树突Ⅰ细胞”,前者具有小型纺锤状的细胞体和垂直伸延的1支尖端树突,后者具有较大三角形或多角形的细胞体和多支上行性树突.多数标记树突的末端部水平分布于视顶盖F层,和终止于此层的视神经终末部的形态相一致.     

Morphological characteristics of tectal neurons of layer I projecting to the nucleus geniculatus lateralis ventralis in chick

Some visual information is sent to the nucleus geniculatus lateralis ventralis (GLv) via the cells in layer I (I cells) of the tectum in birds and is used for color vision, papillary reflex, and kineoptic functions. To reveal the morphological features of 'I cells' projecting to the GLv, they were retrogradely labeled with DiI (1,1'-dioctadecyl-3, 3, 3', 3'-tetramethylindo-carbocyanine perchlorate) in chicks. Two different types of neurons, 'spear dendritic I cells' and 'forked dendritic I cells' were identified. The former had small spindle-like soma and an apical dendrite extending to the tectal surface, and the latter had somewhat larger triangular or polygonal soma and plural ascending dendrites. Most of the labeled dendritic endings bifurcated horizontally in layer F, and showed the ending patterns similar to the terminals of optic nerve fibers.     

Regional Specialisation of the Ganglion Cell Density in the Retina of the Native Duck (Anas platyrhynchos) of Bangladesh

In this study, retinal whole‐mount specimens were prepared and stained with 0.1% cresyl violet for the ganglion cell study in the native duck (Anas platyrhynchos). The total number, distribution and size of these cells were determined in different retinal regions. The mean total number of ganglion cells was 1 598 501. The retinal area centralis had the highest ganglion cell density with 11 200 cells/mm². Number of ganglion cell bodies was the highest in temporal area, followed by dorsal, nasal and ventral areas. Ganglion cell size ranged from 5.25 to 80 μm². In the temporal and nasal region, most of the cells were ranged from 15 to 25 μm², and in the dorsal and ventral region, most of the cells were ranged from 12 to 25 μm². There was a marked trend for the retinal ganglion cell size to increase as the population density decrease towards the periphery. A population of small ganglion cells persisted into the central area just above the optic disc and the largest soma area was in the ventral zone of the retina. Thus, the specialisation of ganglion cell densities and their sizes support the notion that the conduction of visual information towards the brain from all regions of the retina is not uniform, and the central area is the fine quality area for vision in native duck.     

Leukotriene C4 release and gene expressions of IL-8 and MCP-1 in porcine alveolar epithelial type II cells

Leukotrienes (LT) and chemokines are important chemotactic compounds in regulating the recruitment and activation of immune cells during pulmonary inflammatory reactions. Results showed that LTC4 release by porcine alveolar epithelial type II cells (AEC IIs) is significantly enhanced by either LTB4 or LPS stimulation. The basal level of IL-8 gene expression in AEC IIs was only 1/3 of that observed in alveolar macrophages (AMs) while AEC IIs expressed a higher basal level of monocyte chemotactic peptide-1 (MCP-1) and also in response to LPS stimulation than do AMs. The increasing basal and LT-induced MCP-1 gene expressions after 8h of incubation were observed in AEC IIs but decreased in AMs. These findings suggest that AEC IIs play an important role in initial inflammatory reactions of the lung by releasing LTC4, and that they also modulate later inflammatory reactions, evidenced by consistent elevation of MCP-1 gene expression after and during exogenous challenge in pigs.     

Regional specialization of the Ganglion cell density in the retina of the Ostrich (Struthio camelus)

In this study, retinal whole-mount specimens were prepared and stained with 0.1% cresyl violet for the ganglion cell study in the Ostrich (Struthio camelus) . The total number, distribution, and size of these cells were determined in different retinal regions. The mean total number of ganglion cells (three retinas) was 1 435 052 with an average density of 652 cells/mm². The temporo – nasal area of the retina with high cell density were identified with the peak of 7525 cells/mm² in the central area. The size of most ganglion cells ranged from 113–403 µm², with smaller cells predominating along the temporo-nasal streak above the optic disc and larger cells comprising more of the peripheral regions. The average thickness of the retina was 196 µm. The central area was the thickest area (268.6 µm), whereas the peripheral area was the thinnest area. Thus, the specialization of ganglion cell densities, their sizes and the thickness of the retina support the notion that the conduction of visual information towards the brain from all regions of the retina is not uniform, and suggests that the temporo – nasal streak is the fine quality area for vision in ostriches.     

Ganglionic cell distribution in the central area of the beagle dog retina

The distribution of ganglionic cells in the central area of the Beagle dog retina was studied by means of light microscopy in thirteen whole-mount preparations stained with cresyl violet. The central area was composed of two parts termed "the round central area" and the "horizontal streak"; in some specimens the former and in other the latter part was more prominent. The highest concentration of ganglionic cells occured in the round central area (about 7.100 cells/mm²). In other regions of the central area the cells were less numerous and the fewest number was found outside the central area. The size categories of ganglionic cells in the Beagle retina are comparable with those observed in other species.     

金雀异黄酮对鸡骨骼肌卫星细胞脂质过氧化和抗氧化酶活性的影响

为了探明大豆异黄酮主要成分金雀异黄酮(GEN)对鸡骨骼肌卫星细胞的抗氧化保护效应,试验研究了GEN对离体培养的鸡骨骼肌卫星细胞脂质过氧化、抗氧化酶活性和基因表达的影响。试验采用岭南黄羽肉鸡骨骼肌卫星细胞接受不同浓度的GEN处理48h后,测定细胞培养上清液中谷胱甘肽过氧化物酶、超氧化物歧化酶和过氧化氢酶活性以及丙二醛含量,应用TaqMan实时荧光定量PCR法测定GEN对骨骼肌卫星细胞中谷胱甘肽过氧化物酶基因表达的影响。结果表明:与空白对照组相比,添加金雀异黄酮组骨骼肌卫星细胞培养上清液中丙二醛含量显著降低(P<0.05),添加1μmol/L和16μmol/L金雀异黄酮显著提高了鸡骨骼肌卫星细胞培养上清液中超氧化物歧化酶活性(P<0.05),添加4μmol/L和16μmol/L金雀异黄酮显著提高了谷胱甘肽过氧化物酶活性(P<0.05),细胞培养液中添加金雀异黄酮具有提高谷胱甘肽过氧化物酶mRNA拷贝数的趋势(P>0.05)。     

Genetic typing of bovine viral diarrhea virus isolates from Argentina

Genetic typing of 29 Bovine Viral Diarrhea Virus (BVDV) isolates from Argentina was carried out by sequencing 245 nucleotides of the RT-PCR products of the 5'-UTR region. Sequence analysis shows that these Argentinean BVDV include types 1 and 2. The majority (26/29) of the isolates are type 1, which comprises subtypes 1a and 1b, together with an additional subgroup within subtype 1a. This subgroup is close to the South African subgroup Ic of 1a viruses, and to the deer pestivirus strain "Deer". The three type 2 BVDV were isolated from fetal tissues or serum during the 7-8 years before a clinical outbreak in Argentina had been reported. Only inactivated vaccines are used in bovines of the country, thus the analysed viruses are authentic field strains. The long term circulation of type 2 BVDV (situation similar to that of North America before the epidemic of 1993), and the existence of viral populations which differ from the reference strains commonly used in vaccine elaboration should be considered by manufacturers of diagnostic reagents and vaccines.