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Showing 4 results for Animals
Reciprocal effects of cadmium and pH on the intestinal absorption of fatty acids in rat
Amirnader Emami Razavi , Gholam Basati , Soheila Abdi ,
Volume 72, Issue 1 (4-2014)
Abstract
Background: The intestinal absorption of fatty acids may take place through simple diffusion as well as through protein carrier mediated transport, although the relative importance of each pathway is dependent on the ambient condition of entrocytes. Cad-mium ion influences the absorption of fatty acids in entrocytes. However, the effect of cadmium ion on the absorption of fatty acids in different pH values has not been evalu-ated yet. Especially, the luminal pH of small intestine has an essential role in the ab-sorption of fatty acids. In the present study we aimed to evaluate reciprocal effects of cadmium ion and pH of intestine lumen on the absorption of fatty acids in rat model. Methods: In this experimental research, 3 months old Wistar rats (45 rats) were used for experiments. After killing the rats, their intestine was removed and the duodenum and jejunum segments were dissected. Everted Gut Sacs (EGS) were prepared from these duodenum and jejunum segments. The sacs were filled with buffer solution and incubated in a medium containing an appropriate concentration of oleic acid. Then the amounts of oleic acid that had been absorbed into the EGSs in the presence and absence of cadmium ions under different conditions of pH, was measured. Results: Findings of the study demonstrated that the luminal pH of small intestine was effective on the oleic acid uptake and the inhibitory effect of cadmium ions on the up-take of the acid was influenced by pH condition, so that this inhibitory effect was 32% and 36% at the alkaline pHs 7.5 and 9.2, respectively (P< 0.05). At the acidic pHs, 2.5 and 4.5, the inhibitory effect reduced to 11% and 5%, respectively (P< 0.05). Conclusion: Cadmium ion decreased fatty acid uptake by small intestine in rats, and the acidic pH of intestine lumen could attenuate the inhibitory effect of cadmium ion.
Comparison of neurodegeneration between right and left hippocampus area in rats
Arezo Nahavandi , Fatemeh Bakhtiarzadeh , Mansureh Soleimani ,
Volume 72, Issue 11 (2-2015)
Abstract
Background: Depression, as one of the most prevalent and disabling disorders in the world, has a complex and yet not well-known pathophysiology. Genetic, hormonal, neurotransmitter, inflammatory and neurodegenerative theories are all responsible. Studies show that depression leads to structural changes in the hippocampus, prefrontal cortex, amygdala, anterior cingulate, and basal bodies. Hippocampal volume loss is observed due to the death of nerve cells, neurons, and glial cells, and reduced neurogenesis. The hippocampus is a part of the limbic system. The limbic system is the area in the brain that is associated with memory, emotions, and motivation. The limbic system is located just above the brain stem and below the cortex. Despite the many studies related to the reduced hippocampal neurogenesis in depressed patients, no study has compared the amount of neurodegeneration between the left and right hippocampus. In this study, we compared neurodegeneration levels in the right and left hippocampus of the rats. Methods: Twenty male Sprague-Dawley rats that were purchased Razi Institute, Karaj, Iran, were evaluated in the study. This study was conducted in cellular and molecular center in Iran University of Medical Sciences, from June 2012 to June 2013. Half of them had unpredictable chronic mild stress (UCMS) for 21 days to develop depression. The forced-swimming test (FST) was used to measure the immobility time (IB), a symptom of depression. One week after the behavioral test, the rats were prepared for transcardial perfusion. Then, paraffin fixed brain was excised and the hippocampus was prepared for Nissl staining. All above-mentioned procedures were performed for the control group too except inducing UCMS. Results: Our results increased IB in the UCMS group, 68.8 second in stress group and 15.1 second in control group. Nissl staining showed prominent neural degeneration in the hippocampus of the rats in the UCMS group. Comparison of the left and right hippocampal cells revealed that the right hippocampus (mean= 49.166) was more vulnerable to stress than the left hippocampus (mean= 76.6). Conclusion: Our study showed different manifestations of depression after UCMS. It showed that UCMS could lead to mental depression. This study showed that the right hippocampus was more sensitive to stress than the left hippocampus. In fact, UCMS resulted in depression. The study showed that the right hippocampus was more sensitive to stress than the left hippocampus. Therefore, the main function of the right hemisphere, which is adaptation to the new environment, is disturbed more.
Wound healing in animal models: review article
Fariba Jaffary , Mohammad Ali Nilforoushzadeh , Hanieh Sharifian , Zahra Mollabashi ,
Volume 75, Issue 7 (10-2017)
Abstract
Wound healing and reduction of its recovery time is one of the most important issues in medicine. Wound is defined as disruption of anatomy and function of normal skin. This injury could be the result of physical elements such as  surgical incision, hit or pressure cut of the skin and gunshot wound. Chemical or caustic burn is another category of wound causes that can be induced by acid or base contact irritation. Healing is a process of cellular and extracellular matrix interactions that occur in the damaged tissue. Wound healing consists of several stages including hemostasis, inflammatory phase, proliferative phase and new tissue formation which reconstructs by new collagen formation. Wounds are divided into acute and chronic types based on their healing time. Acute wounds have sudden onset and in normal individuals usually have healing process of less than 4 weeks without any residual side effects. In contrast, chronic wounds have gradual onset. Their inflammatory phase is prolonged and the healing process is stopped due to some background factors like diabetes, ischemia or local pressure. If the healing process lasts more than 4 weeks it will be classified as chronic wound. Despite major advances in the treatment of wounds, still finding effective modalities for healing wounds in the shortest possible time with the fewest side effects is a current challenge. In this review different phases of wound healing and clinical types of wound such as venous leg ulcer, diabetic foot ulcer and pressure ulcer are discussed. Also acute wound models (i.e burn wounds or incisional wound) and chronic wound models (such as venous leg ulcers, diabetic foot ulcer, pressure ulcers or bedsore) in laboratory animals are presented. This summary can be considered as a preliminary step to facilitate designing of more targeted and applied research in this area.

Establishment and the importance of chicken pluripotent stem cells and their role in vaccine production: review article
Maryam Farzaneh, Mojgan Hosseini,
Volume 78, Issue 4 (7-2020)
Abstract
Chick embryos are a great historical research model in basic and applied sciences. Along with other animal models, avian and specifically chicken embryo has been attended, as well. Avian fertilized eggs as a natural bioreactor are an efficient tool for producing recombinant proteins and vaccines manufacturing. Due to the limitations of birds' eggs for viral replication, avian stem cells culture technologies access to safe methods as well as large-scale production of a variety of human and animal vaccines. Chicken pluripotent stem cells present the unique property of self-renewal and the ability to generate differentiated progeny in all embryonic lineages such as ectoderm, mesoderm, and endoderm in vitro. For the first time, chicken embryonic stem cells (cESCs) derived from the blastodermal cells of stage X embryos in vitro. Chicken ESC provides a great model of early embryo and they are useful for gene manipulation, virus proliferation, and the generation of transgenic birds. In addition to blastodermal cells, pluripotent cell lines can be produced by reprogramming of chicken fibroblasts into induced pluripotent stem cells (iPSCs) with transcription factors such as OCT4, NANOG, SOX2, KLF4, LIN28, and C-MYC that are well known to contribute to the reprogramming of somatic cells into an iPSCs. Similar to chicken ESCs, iPSCs have properties of unlimited self-renewal in vitro and the capacity for differentiation to all three embryonic germ layers. Chicken iPSCs have been a useful tool for the production of transgenic birds and viral vaccines. Despite the benefits and multiple applications of chicken pluripotent stem cells, the propagation of these cells is limited and some important challenges should be eliminated before their use in vaccine manufacturing. It is necessary to define the appropriate culture conditions for chicken pluripotent stem cells. For example, the presence of endogenous viruses in the avian species should be evaluated for human vaccine production. Currently, primary chicken fibroblast cells are still mainly used for vaccine production. This review covers the resources to achieve chicken derived cell lines for vaccine manufacturing.
 

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