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Showing 5 results for Embryo

Parisa Jonoubi, Ahmad Majd, Aref Marouf, Shahla Amini,
Volume 2, Issue 3 (12-2015)
Abstract

Pimpinella anisum L. belongs to Apiaceae family. The samples of vegetative and reproductive organs at different stages of development were gathered and investigated by cell-histology methods. The investigation of the anatomical structure of vegetative organs showed that the secretory ducts are arranged between the parenchymal tissues of the leaf. Section of flower buds revealed that anthers had 4 pollen sacs, the division of pollen mother cell was of the simultaneous type, microspore tetrads were of tetragonal type and the tapetum layer was secretory. The study of the ultrastructure of pollen grains with SEM showed that they had 3 pores. The ovary was found to be two-chambered and two-carpeled the ovule to be anatropous and to have one membrane. In embryogenic investigation it was found that the embryos were globular, cotyledonary and torpedo-shaped and the transition between globular embryos to cordate embryos was found. The vegetative organs were observed to have the general structure of dicotyledons. The development patterns of ovule and embryo sac follow the Polygonum type. Tetrahedral microspore tetrads were observed. The ultrastructure of pollens was found to be similar to those of Smyrnium, a genus of Apiaceae family. All stages of embryogenesis were covered in this study. 


Elaheh Zamani Bahramabadi, Parisa Jonoubi, Farkhondeh Rezanejad,
Volume 6, Issue 1 (5-2019)
Abstract

The environmental conditions which the parent plant has undergone during seed development can affect many properties of the seeds such as degree of dormancy, weight and the amount of their compounds. In this study, mature pistachio seeds of Ahmadaghaei cultivar, collected from the two cities of Rafsanjan and Shahrbabak located in Kerman Province (Iran), were compared. It was found that the seeds collected from Shahrbabak being a cooler and wetter region had a longer dormancy, although the water content of the two seed series were similar. Dehydrin proteins generally play a role in protecting plant cells against dehydration stress. Dehydrin contents of the cotyledons and embryonic axes of the two seed series were compared by western blot method using an antibody against the conserved K segment in dehydrin proteins. It was found that the cotyledons had five dehydrin versions with molecular weights of 23, 25, 32, 39 and 48 kDa, the expression of which not being influenced by environmental factors. It was found that the embryonic axes had seven other versions of dehydrin with weights of 17, 19, 20, 28, 67, 77 and 98 kDa in addition to those five versions. This shows higher protection of embryonic axes compared with the cotyledons. The 25 and 28 kDa versions had higher expression levels in embryonic axes of Shahrbabak seeds, while the 39 kDa version had a higher expression level in embryonic axes of Rafsanjan seeds.
 
Fateme Mousavi, Ahmad Majd,
Volume 6, Issue 2 (8-2019)
Abstract

Simaroubaceae is a monophyletic family in the order Sapindales with 22 genera and 109 species. Ailanthus altissima (Mill) Swingle, also known as the tree of heaven, is a highly invasive species, which systematically belongs to Simaroubaceae. Reproductive characteristics are essential for the deployment and maintenance of invasive species in new environments and examination of the reproductive system of these species is interesting. To date, no embryological investigations had been directed to A. altissima and our knowledge on the embryology of this species was very limited. A study was carried out on the embryology of A. altissima and the comparison of anther development in male and female flowers in order to gain insights into defining embryological features in this species. According to the results of histological analysis, male flowers have rudimentary gynoecia and anthers are tetrasporangiate. Cytokinesis in meiosis is simultaneous resulting in tetrahedral tetrads. Anther wall development follows the dicotyledonous type and the tapetum is secretory. Female flowers have staminodes and microspore mother cells are degraded too early before entering the course of meiosis. Ovules are anatropous, bitegmic, and crassinucellate. The development of the embryo sac follows the polygonum type. Embryos follow the Onagrad type. The endosperm development is nuclear type. A well-developed hypostase is present and a nucellar cap is formed. These observations will advance our understanding of embryology and embryo anatomy in A. altissima as an invasive species.
 
 
Fatemeh Ghasemian,
Volume 6, Issue 4 (1-2020)
Abstract

One of the most important factors related to male fertility is sperm chromatin status. Under Assisted Reproductive Techniques (ART), especially Intracytoplasmic Sperm Injection (ICSI), the natural selection of high quality sperm with intact chromatin is not possible. Therefore, embryo quality and pregnancy rate decreased for damaged DNA of sperms involved in the fertilization of eggs. Thus, this study evaluated the frequency of abnormal sperm chromatin condensation and damaged sperm chromatin in men with different infertility factors (e.g. oligozoospermia, asthenozoospermia, teratozoospermia, oligasthenoteratozoospermia, and normozoospermia) and ICSI outcomes were examined. 195 patients were examined and the sperm chromatin status was evaluated using aniline blue and toluidine blue staining. Fertilization, zygote and embryo quality, chemical pregnancy and abortion rates were calculated, too. The results showed that in the oligoasthenoteratozzoospermia samples, the damaged chromatin percentage was higher than that in normozoospermia ones. The fertilization rate, embryo quality, and pregnancy rate significantly decreased in this group. Also, a higher abortion rate was observed in this group (P<0.05). In conclusion, the frequency of damaged chromatin was observed to be different in different male infertility factors, which could influence the ICSI outcomes. Therefore, the evaluation of sperm chromatin status before cycle initiation was found to promote ICSI outcomes.
 


Shahin Esmaeilnezhad, Farhad Mashayekhi,
Volume 7, Issue 2 (7-2020)
Abstract

Amniotic fluid (AF) is essential for fetal development and maturation during pregnancy. The levels of proteins in AF have been determined in many studies to screen for potential biomarkers of pregnancy-associated abnormalities. Alpha-fetoprotein (AFP) is a major AF and plasma protein produced by the yolk sac and the liver during the fetal period. APF serum concentrations are commonly used for screening of many syndromes. Electromagnetic fields (EMFs) were reported to change gene expression in the embryo and in adults. The aim of this research was to assess the effects of 50hertz/1millitesla EMFs on AFP expression in the AF in the mouse embryo. AF samples were obtained from pregnant mice in gestational days 16 and 18. AFP relative expression was studied by western blotting. The results of this study showed that AFP relative expression increases in the EMF-treated AF as compared with either SHAM or control groups. It is concluded that EMF increases the AFP relative expression in the AF. It is also suggested that EMF may change the AFP expression in the AF by altering the expression of genes, including AFP, and/or by affecting the permeability of blood barriers.
 
 


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