Farzad Rajaee; Tayyebeh Hadigol; Zivar Salehi; Amir Farzam
Volume 21, Issue 1 , March and April 2015, , Pages 207-215
Abstract
Background and Objectives: Regarding to remarkable growth of population and consequent crowding of it in big cities and immune system sensitivity against environmental agents, the present study aimed to investigate the effects of social stress on spleen of mouse.
Methods and Materials: Thirty adult ...
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Background and Objectives: Regarding to remarkable growth of population and consequent crowding of it in big cities and immune system sensitivity against environmental agents, the present study aimed to investigate the effects of social stress on spleen of mouse.
Methods and Materials: Thirty adult male mice of the NMRI strain were selected at the age of 5-6 weeks and were randomly divided into 2 groups. In control group, 5 animals per cage (3 cages) and in stress group, 15 animals per cage were housed for a period of two months. All animals were anesthetized with an intrapritoneally injection of ketamine and xylazine after two months. The sample of blood from left ventricle of heart was provided by heparinized syringe. Serum samples were used for hormonal study by radioimmunoassay. Spleen was weighted after removing and the samples of spleen were fixed for light microscopic study. The mean numbers of macrophage and megakaryocyte cells were determined. The data has been compared using statistical methods (t-test and Mann-Whitney test).
Results: The mean weight of spleen and corticosterone level of serum was insignificantly reduced in stress group compared to control group. The mean numbers of macrophage cells in stress group were insignificantly increased compared to control group. The results showed that the mean numbers of megakaryocyte cells were significantly reduced between stress and control group(P=0.007).
Conclusions: The results showed that the crowding stress can be resulted in decreased number of megakaryocyte cells whereas no significant effect on macrophage cells, serum cortisol hormone level and weight of spleen were found. However, further studies in this area are needed to confirm it.
Mahnaz Azarnia; Seyyed Homayoon Sadraee; Franak Najd; Gholamreza Kaka; Mohammad Kamalinejad
Volume 21, Issue 6 , January and February 2015, , Pages 985-992
Abstract
Background: The aim of this study was to evaluate the effects of Elaeagnus Angustifolia extract on mouse embryonic development of Balb/c.
Materials and Methods: Thirty pregnant mice were randomly divided into two groups. Control group consumed drinking water, and the experimental group during pregnancy ...
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Background: The aim of this study was to evaluate the effects of Elaeagnus Angustifolia extract on mouse embryonic development of Balb/c.
Materials and Methods: Thirty pregnant mice were randomly divided into two groups. Control group consumed drinking water, and the experimental group during pregnancy received the aqueous extract at a dose of 500 mg/ kg. Pregnant mice were killed at 18th gestation day and fetal and placental weight and length of the crown-rump of fetuses were measured and recorded. After fixation and tissue processing, liver embryos were taken out and tissue sections were prepared. After staining with hematoxylin-eosin, histomorphometry was investigated. Then obtained results were statistically analyzed.
Results: No apparent abnormality was observed in embryos. The mean of crown-rump length of fetuses in the experimental group was not shown a significantly increased than control group. The mean of fetal weight in the experimental group was significantly decreased than control group. The mean weight of the placenta in the experimental group was significantly reduced compared to control group. In a histomorphomety analysis in the embryo liver of experimental group, with regard to the mean of size percentage of sinusoids and mean number of blood cells significantly increased in experimental group compared to control group. The mean total surface that occupied by hepatocyte and Mean number of hepatocyte nuclei significantly decreased in experimental group compared to control group.
Conclusion: It seems prescribing aqueous extract of Elaeagnus Angustifolia at dose of 500 mg/kg to pregnant mice can cause developmental abnormalities in the fetus and placenta.
M JALALI; MR NIKRAVESH
Volume 14, Issue 1 , March and April 2007, , Pages 44-52
Abstract
Background and Purpose: At least two different elements can be detected in the structure of mature intervertebral disc. The central portion contains nucleus pulpous. Its few cells being embedded in gel form material. The outer protein, however, is called annulus fibroses, composed of concentric layers ...
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Background and Purpose: At least two different elements can be detected in the structure of mature intervertebral disc. The central portion contains nucleus pulpous. Its few cells being embedded in gel form material. The outer protein, however, is called annulus fibroses, composed of concentric layers of intertwined annulus bands. Although the major anatomical structures of intervertebral disc are well known, there are little information on the development of its components such as cell type and extracellul matrix. Therefore, this study was conducted to study the histological changes in the development of intervertebral disc in mouse.
Methods and Materials: In this study, collagen fiber appearance and cellular differentiation were studied using serial section and histological staining methods in the course of intervertebral disc development in mouse embryo.
Results: The findings indicated that from the 12th day of gestation, the notochord starts getting separated from the floor plate of neural tube. Gradually on the next days, as mesenchyme cells get condensed around, patterns of intervertebral disc differentiation can be observed, leading to disc development toward the end of gestation. Throughout this process, the notochord degenerates. Theses changes start from the middle portion of notochord and proceeds towards head and tail. Then vertebral bodies are forward in portions with degenerated notochord changes.
Conclusion: During the development changes of intervertebral disc, remnants of notochord form nucleus pulpous in the intervertebral disc. However, the mesenchyme surrounding it (forthcoming annulus fibrosus) consist of structurally dissimilar regions. Under these circumstances, the outer portion is made up of highly-densed collagen material but in the inner portion, remnants of embryonic hyaline cartilage and collagen fibers can be detected.