Unraveling avian and reptilian hematology: An optical and electron microscopic study of the buffy coat

Background

Blood centrifugation and buffy coats are at the cornerstone of hematology. In mammals, the buffy coat has a layered disposition (from bottom to top) with neutrophils on top of erythrocytes, followed by monocytes/lymphocytes, and platelets. In nonmammals, this distribution is unknown. Recently, the cell tube block (CTB) technique was developed to study the buffy coat, but it was never applied to nonmammal buffy coats.

Objectives

This study aimed to evaluate using the CTB technique to study reptilian and avian buffy coats and to propose its use for clinical applications.

Methods

Blood from five birds and eight reptiles of different species was obtained to make CTBs that were processed for optical/electron microscopy. H&E, Sirius red, and immunohistochemistry staining against CD3 (to label T lymphocytes) were applied to the CTBs.

Results

In birds, the buffy coat had a layered appearance with the granulocyte layer containing granulocytes (heterophils and eosinophils) and nucleated erythrocytes followed by a mononuclear cell layer containing lymphocytes, monocytes, and thrombocytes. In some animals, a nucleated erythrocyte layer was observed admixed with the granulocyte/mononuclear cell layer. A small clot within the buffy coat was seen in seven reptiles, and less definition of layers occurred in reptiles, with only one or two layers. Lymphocytes appeared toward the top of the buffy coat.

Conclusions

From a comparative hematology perspective, the buffy coat of mammals differs from that of birds and more from that of reptiles. The CTB technique can be used to study these differences in avian and reptilian hematology, especially to study atypical circulating cells, hemoparasites, or blood cell proportions in health and disease.     

Ultrastructure of Seed Coat Development in the Natural Tetraploid Trifolium pratense L.

Seed coat development in the natural tetraploid Trifolium pratense L. was studied by electron microscopy. The mature seed coat derived from the outer integument is composed of three layers of cells. The cells of the outer epidermis divide anticlinally and undergo radial elongation to form a macrosclereid layer. The cells are characterized by thin walls, the presence of amyloplasts, and numerous vacuoles which are completely or incompletely filled with tannin. The outer tangential walls are thickened at an early stage. An electron-translucent cap develops in the outer tangential walls of the macrosclereid cells at the globular embryo stage. Osteosclereid cells are highly vacuolate with densely staining cytoplasm. Gradually, extensive intercellular spaces are formed. The parenchyma cells are small and have prominent intercellular air spaces. Maturation eventually leads to the disappearance of cytoplasm in all cells, and the compression of the cells of the parenchyma layer.     

Water Uptake by Seeds in Yellow-seeded Soybean (Glycine max (L.) Merrill) Cultivars with Contrasting Imbibition Behaviors

Abstract

The rate of water uptake by seeds is assumed to be an important factor affecting the susceptibility of seeds to flooding injury, but the traits which could contribute to restricting rapid imbibition by seeds remain undetermined in yellow-seeded soybeans. This study was conducted to determine the possible factors controlling the rate of imbibition in soybeans with yellow seed coats. The imbibition behavior of two yellow-seeded cultivars, Tamahomare and Tachinagaha, with different flooding susceptibilities was examined in relation to initial seed moisture content, the hydration location of the seed surface during imbibition, and the state of the seed coat. Low seed moisture increased the water uptake by Tamahomare intact seeds and even allowed substantially faster imbibition than occurred in its embryos, while in Tachinagaha seed moisture content had little influence on seed imbibition. This rapid imbibition by low-moisture Tamahomare seeds was not due to alterations in the permeability of the seed coat nor in water uptake by the embryo, but rather to increased movement of water along the abaxial sides of the cotyledons. The seed coat of Tamahomare loosened readily upon submergence whilst that of Tachinagaha rather tightly adhered to the embryo, suggesting that the seed coat of Tamahomare adheres very loosely to the embryo and may aid in conducting water laterally between the seed coat and embryo. The degree of adherence of the coat to the embryo and/or the ease with which the coat can be loosened upon hydration appear to play a crucial role in determining the rate of water uptake in yellow-seeded soybeans.     

休眠期不同的春小麦种子种皮结构形态观察

观察表明:休眠期不同的春小麦种子种皮结构,在细胞层次上没有实质性差异,而外表皮的细胞形状,排列明显不同。休眠期长的品种,外表皮细胞排列整齐而紧凑,呈长方形;休眠期短的品种,外表皮细胞排列疏松,不整齐,多呈卵圆形,种皮的厚度与休眠无关。小麦种皮主要通过限制胚部的氧气供应,及对胚起物理阻碍作用而诱导休眠。     

半巢式-RT-Realtime PCR检测李痘病毒

李痘病毒(Plum pox virus,PPV)是我国重要的植物检疫性有害生物。本研究根据PPV中CP基因(coat protein gene)的保守序列,设计了3条PCR引物和1条TaqMan探针,建立了半巢式-RT-RealtimePCR检测PPV的方法。该方法有机地结合了巢式PCR和实时荧光PCR技术;3条引物形成的2套PCR体系相互验证,有效提高了结果的准确性;荧光探针有效提高了检测的灵敏度。实验结果表明,本方法准确、灵敏、简便、快速,检出低限可达37fg/μL植物总RNA。     

Inheritance and molecular markers for the seed coat color in Brassica juncea

To elucidate the inheritance of seed coat color in Brassica juncea, Sichuan Yellow inbred (PY) was crossed with the Ziyejie inbred, and their F₁, F₂ and BC₁ and BC₂ progenies, derived from backcrossing to PY, were phenotyped for seed coat color. Results showed that the yellow seed coat was controlled by two independent recessive loci. Seven brown-seeded near-isogenic lines were developed by successive backcrosses to PY and by selfing. One of the BC₆F₂ populations segregated for a single locus controlling seed coat color was used for mapping. Using the 88 primer pairs from sequence-related amplified polymorphism and the 500 random primers, two markers were found to be linked to the gene for brown seed coat, which were designated as SCM57 and SCM1078. The crossover between these markers and the brown seed coat loci was 2.35% and 7.06%, respectively. A sequence characterized amplified region (SCAR) marker according to Negi et al. (2000), designated as SZ1-331, was found to be linked to the gene for brown seed coat, with a crossover estimate of 2.35%. The markers were located on the same side of the brown seed coat loci and 2.41, 7.51 and 2.41 cM away from the brown seed coat locus. The seven brown-seeded near-isogenic lines were classified into two groups by three DNA markers. They were located at the same linkage group of the marker RA2-A11 previously published by Padmaja et al. (2005).     

Environmental and genetic variation of the effective radiative properties of the coat of Holstein cows under tropical conditions

Morphological characteristics, coat effective radiative properties, and the percentage of white colour were measured in the coats of 973 Holstein cows, and estimates of the genetic parameters were obtained for these traits, except morphological characteristics. The results showed that white coats are more dense with long, thin hairs, while the black coats are less dense with short, thick hairs. Effective transmissivity is greater in the less-dense coats with short, thin hairs, independently of coat colour. Effective reflectivity depends more on the variation in the radiative properties of the coat and skin surface rather than on the morphological characteristics of the coat. Effective absorptivity is greater in black and dense coats with long, thick hairs, than in the white and less-dense coat with short, thin hairs. All heritability estimates were of low magnitude, except for the percentage of white coat colour.     

不同种粒抗性大豆品种感染SMV后可溶性蛋白和游离氨基酸的研究

 采用感斑驳品种合丰25、丰收12,抗斑驳品种东农81-43、铁6915(东农),在隔离网室内进行盆栽试验,于对生真叶期分别接种SMV1号、3号株系,以未接种健株为对照,在鼓半粒期分析种皮游离氨基酸和可溶性蛋白含量。结果表明:抗斑驳品种健株种皮中可溶性蛋白含量显著高于感斑驳品种,说明种皮中可溶性蛋白含量与种粒抗性成正相关,可作为筛选抗斑驳品种的生化指标。感斑驳品种中未检测到甲硫氨酸,抗斑驳品种含有甲硫氨酸,甲硫氨酸能抑制色素的形成。接种SMV后,感斑驳品种种皮中可溶性蛋白含量增加,抗斑驳品种可溶性蛋白含量降低。感斑驳品种种皮中苏、苯丙、异亮、缬氨酸含量增加,抗斑驳品种上述氨基酸含量降低或维持不变。这些氨基酸能促进色素的形成,可能与种皮斑驳的形成有一定关系。     

Molecular evidence for the occurrence of beet western yellows virus on chickpea in Morocco

A luteovirus isolate infecting chickpea in Morocco was experimentally transmitted by Myzus persicae to Physalis floridana, on which it produced mild symptoms. When tested in western blots against antisera to known legume luteoviruses, this isolate reacted strongly to beet western yellows virus (BWYV) antiserum, moderately to bean leafroll virus antiserum, while no reaction was recorded with the antiserum against subterranean clover red leaf virus. In PCR, a fragment of ca. 950 bp was amplified, comprising the 3' end of the open reading frame (ORF) 3, the complete coat protein gene (ORF 4), and the non-translated region in between these ORFs. The nucleotide sequence of the amplified fragment showed high similarity with BWYV (approximately 96%), and lower (50–60%) with other luteoviruses reported to infect legumes. On the basis of these data, the Moroccan isolate was identified as BWYV. This is the first molecular evidence for the occurrence of BWYV on chickpea in Morocco, and on food legumes in general in North Africa.