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Introduction: Electrical impedance tomography (EIT) is a non-invasive technique utilized in various medical applications, including brain imaging and other neurological diseases. Recognizing the physiological and anatomical characteristics of organs based on their electrical properties is one of the main applications of EIT, as each variety of tissue structure has its own electrical characteristics. The high potential of brain EIT is established in real-time supervision and early recognition of cerebral brain infarction, hemorrhage, and other diseases. In this paper, we review the studies on the neurological applications of EIT. Methods: EIT calculates the internal electrical conductivity distribution of an organ by measuring its surface impedance. A series of electrodes are placed on the surface of the target tissue, and small alternating currents are injected. The related voltages are then observed and analyzed. The electrical permittivity and conductivity distributions inside the tissue are reconstructed by measuring the electrode voltages. Results: The electrical characteristic of biological tissues is remarkably dependent on their structures. Some tissues are better electrical conductors than the others since they have more ions that can carry the electrical charges. This difference is attributed to changes in cellular water content, membrane properties, and destruction of tight junctions within cell membranes. Conclusion: EIT is an extremely practical device for brain imaging, capturing fast electrical activities in the brain, imaging epileptic seizures, detecting intracranial bleeding, detecting cerebral edema, and diagnosing stroke. [ABSTRACT FROM AUTHOR]

Background: Testicular damage due to spermatic cord torsion may lead to infertility. It is probably because of changes in oxidative stress factors such as malondialdehyde. Objective: To investigate the protective effect of melatonin (MLT), as an antioxidant, on testicular damage induced by acute unilateral spermatic cord torsion and detorsion (T/D) in rats. Materials and Methods: In this experimental study, 48 adult male Wistar rats were randomly divided into three groups (8 rats/group): sham group underwent right scrotal surgery only., the T/D group underwent right testicular torsion (for 1 hr) and detorsion, and the melatonin group underwent right testicular torsion, received 25 µg/kg melatonin intraperitoneally immediately after surgery of T/D. Then the histological parameters and malondialdehyde (MDA) changes were evaluated. Results: Torsion and detorsion decreased the diameter of the tubules significantly compared to controls (p=0.003). Melatonin could increase the diameter, but it was not significant (p=0.26). The heights of the epithelium were constant in sham, T/D, and melatonin groups without any significant difference between groups (p=0.98). Based on Johnsen's score, spermatogenesis was normal in the sham group. The torsion significantly injured all lineage cells (p<0.001). There was no any spermatid or sperm in the seminiferous tubules. Melatonin improved the spermatogenesis significantly (p=0.02), but could not improve MDA level significantly (p=0.99). Conclusion: Severe degenerative changes of testis were induced by acute unilateral spermatic cord torsion and detorsion in rats, but it had no effect on MDA level. [ABSTRACT FROM AUTHOR]

Background: After improvements in various cancer treatments, life expectancy has been raised, but success in treatment causes loss of fertility in many of the survived young men. Cryopreservation of immature testicular tissues or cells introduced as the only way to preserve fertility. However, freezing has some harmful effects. Melatonin, a pineal gland hormone, has receptors in reproductive systems of different species. It is assumed that melatonin has free radical scavenger properties. Objective: The aim of this study was to evaluate the effects of melatonin on the cryopreserved testicular cells in mouse. Materials and Methods: Cells from 7- 10 days old NMRI mice testes were isolated using two step enzymatic digestion. The testicular cells were divided into two groups randomly and cryopreserved in two different freezing media with and without the addition of 100 μm melatonin. Finally, apoptosis of the cells was assayed by flow cytometry. Also, lactate dehydrogenase activity test was performed to assess the cytotoxicity. Results: The results of lactate dehydrogenase showed the nearly cytotoxic effect of melatonin. The results of flow cytometry showed increase in apoptosis in the cryopreserved cells in the media containing melatonin compared to the control group. Conclusion: The present study shows that melatonin has an apoptotic effect on cryopreserved mouse testicular cells. [ABSTRACT FROM AUTHOR]

Context: Curcumin is a yellow-orange polyphenol derived from turmeric [ Curcuma longa L. (Zingiberaceaerhizomes)]. Turmeric is a main ingredient of Indian, Persian, and Thai dishes. Extensive studies within the last half a century have demonstrated the protective action of curcumin in many disorders of the body. Objective: This study evaluated the protective effect of curcumin on dexamethasone-induced spermatogenesis defects in mice. Materials and methods: Thirty-two NMRI mice were randomly divided into 4 groups. The first (control) group received 1 mL/day of distilled water by intraperitoneal (i.p.) injection for 7 days. The second group received 200 mg/kg/day of curcumin (Cur) for 10 days. Third group received 7 mg/kg/day of dexamethasone (Dex) for 7 days. Forth group received 200 mg/kg of curcumin for 10 days after dexamethasone treatment. Testicular histopathology, morphometric analysis, head sperm counting, and immunohistochemistry assessments were performed for evaluation of the dexamethasone and curcumin effects. Results: Expression of Bcl-2 was significantly increased in the curcumin + dexamethasone group compared with dexamethasone-treated animals ( p < 0.05). Dexamethasone induced spermatogenesis defects including epithelial vacuolizations, sloughing of germ cells, reduction of seminiferous tubule diameter, reduction in the number of sperm heads and significant maturation arrest ( p < 0.001). Curcumin + dexamethasone treatment significantly prevented these changes ( p < 0.05). Discussion and conclusion: The results of this study demonstrate that curcumin increases the expression of Bcl-2 protein, an important anti-apoptotic factor, and improves the spermatogenesis defects in dexamethasone treated mice. Curcumin has a potent protective effect against the testicular toxicity and might be clinically useful. [ABSTRACT FROM AUTHOR]

Background and purpose: Delayed wound healing is a common complication of diabetes mellitus. However, less is known about the cause of this pathology. Types of skin cells, extracellular matrix and variety of growth factors are involved in wound healing. The use of recombinant growth factors in researches and production of skin substitutes are still a challenge. Much research has been done on the effects of gene therapy and cell therapy in wound healing. This experimental study assessed the effect of insulin-like growth factor (IGF-1) over expression in combination with fibroblast cells therapy to diabetic wounds in rats. Material and methods: Diabetes was induced in rats using Streptozotocin. Fibroblasts were cultured and transfected with IGF-1. Lipofectamine 2000 was used as reagent transfection and transgene expression levels were measured by ELIZA. To study the in vivo, rats (weighing 170-200g) were randomly divided into three groups (5/group) and full-thickness wounds were created on the dorsum region. Suspensions of transfected fibroblast and native fibroblast cells were injected into the wound and were compared with the wounds treated with normal saline. For microscopic examination, biopsy was performed on day 8. Results: In in vitro, the maximum expression of IGF-1 in transfected fibroblast cells (96.95 pg/ml) was 24 h after gene transfer. In vivo, IGF-1 gene therapy increased the number of fibroblast and keratinocyte cells in wound healing process. Granulation tissue formation in transfected fibroblast and native fibroblast cells groups compared with the normal saline group were found to be more organized. Conclusion: The expression of IGF-1 increased by optimization of gene transfer. High concentrations of IGF-1, in combination with cell therapy, had a significant effect on delayed wound healing in diabetic rats. [ABSTRACT FROM AUTHOR]

Objective: Utilization of the autologous and allogeneic skin substitutes seems to be a promising treatment option. In this study, the authors used amniotic membrane covered with cultured allogenic fibroblast as a skin substitute in the treatment of acute wounds., Materials and Methods: Full-thickness wounds were created on rats' dorsum regions and treated with cultured allogenic fibroblast on an acellular amniotic membrane (AAM+F), an acellular amniotic membrane (AAM) alone, an allogenic fibroblast suspension (AFS), or normal saline as a control (C). Specimen biopsies were obtained 7 days after wounding. Quantitative wound healing parameters including the epidermal thickness, the mean number of keratinocytes, fibroblasts, and lymphocytes were assessed., Results: All transplanted wounds exhibited significantly further contraction compared with the nontransplanted wounds. Wounds transplanted with AAM+F and AAM showed a significant increase in epidermal thickness compared to nontransplanted wounds. Wounds transplanted with AAM+F or AAM showed improved epidermal healing compared to nongrafted wounds. Furthermore, granulation of tissue formation in the AAM+F group was more organized when compared to AFS and the normal saline groups., Conclusion: Quantitative assessment of the full-thickness wounds showed transplantation of AAM+F and AAM better improve wound healing parameters when compared to treatment with AFS and the normal saline groups.