Introduction: Sperm Viability Test is important in diagnosis and treatment of male infertility. The common test is E&N and HOST which they are based on membrane permeability and integrity. The aim of this study was to evaluate MTT Assay as a sperm viability test based on mitochondrial activity. Materials and Methods: Washed sperm samples were co-incubated with MTT in different media and different times in order to obtain the best condition for carrying out MTT assay. Then coefficient of variation of MTT was obtained and sensitivity and specificity of each test were calculated. Then MTT and E&N and HOST were carried out on 57 samples from infertile patient referring into Isfahan Fertility and Infertility Center. Then correlation coefficient of these tests with each other and sperm motility were obtained using SPSS software statistical program.Results: Ham's F-10 + 15 mM Hepes + 10% HSA at pH=7.4 at 37° c for 2 hours were the best condition for carrying out Sperm MTT Viability Assay in order to obtain optimal results. MTT assay showed a good significant correlation with HOST and E&N and sperm motility. All the test had high sensitivity but the specificity of HOST was less than that of E&N and MTT.Conclusion: MTT assay appears to be a suitable sperm viability test with high sensitivity and specificity and low coefficient of variation. This test designed not only for differentiating but also selecting and sperating viable sperm from dead sperm. Therefore this test may have an application for intra-cytoplasmic immotile sperm injection which remains to be study.

Spinal cord slice culture from mammals is one of important methods for studing spinal cord injury, evaluation of cell viability and cell death mechanisms. The aim of this study was to establish an in vitro model for culturing spinal cord slice by MTT [3 – (4, 5- dimethy lthiazol-2-yl) -2, 5-diphenyl tetrazolium bromide] assay. The thoracic region of spinal cord from adult mouse was transversally sliced to 300-600 μm, using a tissue chopper. The slices were incubated with culture media in the presence or absence of serum for different period of time. MTT assay was used to assess the viability of the slices. After 24 h, 400-μm-thick slices displayed a significant increase (P<0.01) in viability compared to both thinner and thicker slices. At this time point, a significant increase (P<0.001) was found in the viability of slices cultured in serum containing medium compared to serum free medium. Qualitative MTT assay also revealed an intense staining in both gray and white matter of freshly prepared slices. However, after 24 h, the distribution of MTT staining was less pronounced in the slices particularly in slices cultured in serum-free medium compared to serum containing medium. Our results suggest that MTT assay is a useful tool for evaluating adult mouse spinal cord slices and that both slice thickness and the presence of serum into the medium affect viability in such slices.

Background: 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay which evaluates cellular mitochondrial activity is widely used for the assessment of cell proliferation and viability. Objective: This study was performed to assess human sperm viability using MTT assay. Materials and Methods: In this laboratory study, human-ejaculated semen samples (n = 56 from different donors) were used. The sperm viability was determined using quantitative MTT assay and the sperm motility was assessed according to World Health Organization guidelines. Sperm viability and the correlation between sperm viability and motility were analyzed. Results: Data revealed a marked positive correlation between MTT reduction rate and the percentage of viable spermatozoa. The Pearson’ s correlation coefficients also showed a significant correlation between sperm viability and motility. Conclusion: MTT assay which is based on mitochondrial functionality is a reliable method for evaluating human sperm viability and could be used as a diagnostic test for predicting sperm fertilization ability in clinical settings.

Background: Macrophages have important role in defense against Herpes Simplex Virus type-1 (HSV-1). The present study was performed to determine the viability and nitric oxide (NO) production by HSV-1 infected mouse peritoneal macrophages (HIM). Method: The viability of macrophages was evaluated using MTT reduction assay and the production of nitrite using Griess method. Results: The ability of infected macrophages to reduce Tetrazolium (MTT) was diminished at virus to cell ratios of multiplicity of infection (MOI) of one, three and 10; but not at 0.01and 0.1. Induction and inhibition of NO production by HIM were MOI dependent. The basal NO production by these cells was inhibited at MOI of three and ten. In contrast virus to cell ratios of 0.01 and 0.1 induced low but significant enhancement in NO production. The inability of HIM to reduce MTT at MOI of three was significant after 12-hrs and inhibition of NO production was initiated between 12-20 hours after infection. Conclusion: High doses of HSV-1 seem to decrease the normal activity of macrophages by inhibiting the production of nitric oxide.

Introduction: The aim of this study was to evaluate the effect of human sperm MTT viability assay on outcome of intracytoplasmic sperm injection. MTT is a tetrazolium salt, routinely used for cell proliferation and cytotoxicity assays. Materials and Methods: 50μl of processed semen was treated with MTT solution, while the remaining used as the control. Meanwhile, 109 donated human oocytes (metaphase II) obtained from 12 patients were divided into two groups. Fifty five oocytes were injected using MTT positive sperms, while 54 oocytes were injected with sperms from the control group. Then the injected oocytes were cultured and observed at 18, 42, 66, 90, and 114 hours pos- ICSI. Finally, the fertilization and embryo development rates were compared in both groups. Results: No significant differences were observed between fertilization and embryo development rates in the MTT and control groups. Conclusion: In future studies after approving that the MTT has not cytotoxic or teratogenic effects, then sperm MTT viability assay might be useful for ICSI in patients with absolute or severe asthenospermia or in patients with highly deformed sperm tails.

Background and Objective: In recent years the incidence opportunistic fungual infections has in creased dramatically. One of the most common fungal pathogen Candida dubliniensis, colonization and biofilm formation on the surfaces of medical devices. The aim of this study was to evaluate the inhibitory activity of zinc oxide nanoparticles against C. dubliniensis biofilm formation by the MTT colorimetric method is measured.Materials and Methods: In this study, ZnO nanoparicles using the sol-gel was prepared, size and type of particles, respectively, by scanning electron microscopy (SEM) and X-Ray-Diffraction were determined. The Minimum inhibitory concentration (MIC) of growth dilution method was done by microdilution test.C. dubliensis biofilms (DSY 1024) after 48h incubation at 37oC inhibited the information of nanoparticles ZnO, SDS and Fluconazole drug as a positive control on Candida biofilms was assessed by MTT tetrasolium salt reduction. The collected data using statistical t-test and SPSS software were analyzed.Results: The results of this study showed that a minimum concentration of inhibitor nanoparticles, ZnO, SDS and fluconazole, respectively: 9.25, 0.02, 8 mg/ml. Inhibitory strength of biofilm adhesion in the presence of nanoparticles ZnO, SDS and fluconazole, equivalent to more than twice the concentration of the MIC was determined.Conclusion: In this study, ZnO nanoparticles synthesized by a chemical method indicat that has anti-fungal properties. Therefore, a new way of working for the prevention of biofilm formation of Candida biofilms particularly associated with medical devices to be.

Background: Zinc has significant effects on structural and functional activities of many proteins and enzymes involved in biological activities, especially the regulation of immune-system.Symptoms of zinc toxicity include nausea/vomiting, fever, cough, diarrhea, fatigue, neuropathy, and dehydration. Further signs include growth retardation, altered iron function, anemia, copper deficiency, decreased immune function, decreased HDL (high density lipoprotein), increased LDL (low density lipoprotein), and increased HgbA1C.This study was carried out to examine the invitro effects of different concentrations of zinc on viability and death of T-lymphoid (Raji) cell line.Methods: In this study, the cell line was exposed to different concentrations of zinc (10nanoM to 500microM) followed by incubation (37° C, 5% CO2) at various time points (12 to 72 h). The cells were, then, evaluated using trypan blue exclusion dye, MTT assay (mitochondorial thiazol tetrazolium), and light microscopy.Results: The results of this study showed almost different responses to different amounts of zinc in the T cell line (Raji). Zinc concentrations below 100mM at different incubation time points had little or no effects on the cell line compared to the controls. Higher concentrations of zinc viability (>10mM) diminished to 70% at 12 hour and less than 50% at 24 to 72 hours of incubation.Conclusion: It can be concluded that zinc has a dose-dependent cytotoxicity effect on Raji cells.

Background and purpose: Infection remains the major problem of the burned patients. Factors such as disruption of the integrity of the skin, vast antibiotic treatment which causes loss of the normal flora of the body and impairment of phagocytotic system, contribute to the increased susceptibility to mycotic infections. Among the fungi, Candida albicans which is an opportunistic microorganism and one of the normal flora of the body, causes the most dreaded septic complications in thermal injured patients. Neutrophils with their phagocytotic activities are effectors cells especially essential for protection against fungal infections.Post burn impairment of PNL cells activity as a result of intrinsic defect or alternation in opsonic activity of serum has been reported.Materials and methods: In this study the Candidiacidal activity of neutrophils in 30 patients with second and third degree burns and 30 aged matched normal persons were compared using MTT assay for determination of fungal viability. Candida specimens were prepared by serial passage of a standard species on sabouard dectrose agar (SDA). Yeast were grown overnight in yeast-nitrogen base broth (YNBA). In using them for experiment the viability of all specimens were more than 90%. Neutrophils were obtained from whole blood by dextran sedimentation followed by ficoll separation. The neutophil of patient and normal controls were cultured and normal and patient serum was added as opsonins after an hour of incubation with candida samples. Neutrophils were lysed by addition of dexycholic acid and the viability of remaining yeasts was measured using MTT assay. Statistical analysis was done using student t-test and variance analysis.Results: Our results indicated an increase in neutrophil abundance in patients blood as compare to healthy individuals. But the candidiacidal activity of patients neutrophils was significantly decreased. The observed decrease of activity was not only related to intrinsic defect of cells, but also to serum changes. So that when adding patients serum to normal neutrophils the killing activity was also significantly reduced.Conclusion: Considering the above results if we can increase the neutrophil activity of burned patients using cell stimulator drugs or cytokines which is the scope of another study we can hope to reduce the infectious problems of thermaly injured patients. Specially the fungal infections.