The Regression of Glioblastoma Multiforme is Time Dependent in the Wild-type Rat Xenograft Model.

Introduction: Glioblastoma multiforme (GBM) is an aggressive case of primary brain cancer which remains among the most fatal tumors worldwide. Although, some in vitro and in vivo models have been developed for a better understanding of GBM behavior; a natural model of GBM would improve the efficiency of experimental models of human GBM tumors. We aimed the present study to examine the survival and durability of U87 cells in the brain of wild-type rats. Methods: U87 cells were intracranially implanted in twenty-one wild-type rats. Tumor size and morphology as well as infiltration of immune cells were investigated at three-time points by H&E and immunohistochemistry (IHC). Results: The results demonstrated that the inoculation of GBM cells led to the infiltration of host defense system cells which caused immunological regression of the tumor mass after six weeks. While the tumors successfully developed without any sign of host defense invasion in the second week of GBM inoculation. Also, a decrease in tumor size and infiltration of immune system cells were observed in the fourth week. Conclusion: These data remarkably suggest that time plays a crucial role in activating the immune system against human GBM tumors in rats; it shows that the regression of tumor mass depends on a time slope. Highlights: A noticeable proliferation of tumor cells was observed in the rat's brain by the second week.The distant metastatic masses of cancer infiltrated into the adjacent normal tissue by the second week.Tumor mass underwent a noticeable diminution in the size by the fourth week.Cancer cells completely regressed by the sixth week due to immunological reactions.In tumor rejection, the effective mechanism depends on immune system activity and the slope of time. Plain Language Summary: One of the most malignant tumors is the brain tumor in the world. Unfortunately, no effective treatment has yet been found for it. Of course, researchers need efficient animal models to find the appropriate treatment. The xenograft model is one of the tumor models in the laboratory. However, the main challenge is the interaction of the animal's immune system with induced-cancer cells so that the immune system finally rejects the tumor. In this study, we investigated how long the immune system needs to reject induced tumors in the xenograft model completely. For this purpose, we studied the animals in three periods (second week, fourth week, and sixth week). We concluded that the immune system does not recognize the induced cancer cells until the second week of the experiment. It results in the growth of cancer cells and the formation of tumors in the animal brain. However, the immune system begins to recognize the tumor mass after the fourth week which leads to a reduction in metastasis and tumor size. Eventually, the immune system completely rejects the formed tumor in the sixth week.

In-vivo and in vitro assessments of the radioprotective potential natural and chemical compounds: a review.

PURPOSE: The study of the radioactive role of natural and chemical substances on human and animal studies has been the subject of research by some researchers. Therefore, the review of some of the past and current studies conducted in this field, can provide helpful information to elucidate of the importance of radioprotective components in reducing radiation exposure side effects. METHODS: The authors search for keywords including In vitro, In vivo, Radioprotective, Ionizing radiation, and Vitamin in ScienceDirect, Scopus, Pubmed, and Google Scholar databases to access previously published articles and search for more reference articles on the role of radioprotective materials from natural and chemical compounds. RESULTS: Radiation exposure can produce reactive oxygen species (ROS) in the body, however most of which are eliminated by the body's natural mechanisms, but when the body's antioxidant systems do not have enough ability to neutralize free radicals, oxidative stress occurs, which causes damage to DNA and body tissues. Therefore, it is necessary use of alternative substances that reduce and inhibit free radicals. CONCLUSION: In general, recommended that antioxidant component(s) can be protect tissue damages in humans or animals, due to the their ability to scavenge free radicals generated by ionizing radiation.

Sodium Cobalticarborane: A Promising Precatalyst for Oxygen Evolution Reaction.

Water splitting is a helpful way of converting renewable electricity into fuel. The oxygen evolution reaction (OER) is a slow reaction that provides low-cost electrons for water reduction reactions. Thus, finding an efficient, low-cost, stable, and environmentally friendly OER catalyst is critical for water splitting. Here, sodium cobalticarborane (1) is introduced as a promising precatalyst for forming an OER cobalt-based catalyst. The cobalt-based catalyst was characterized by several methods and is suggested to be Co(III) (hydr)oxide. Using fluorine-doped tin oxide, glassy carbon, platinum, and gold electrodes, the OER activity of the cobalt-based precatalyst was investigated. The overpotential for the onset of OER in the presence of 1 is 315 mV using fluorine-doped tin oxide electrodes. The onsets of OERs in the presence of 1 using gold, platinum, and glassy carbon electrodes in KOH solutions (1.0 M) turned out to be 275, 284, and 330 mV, respectively. The nanoparticles on the gold electrodes exhibit significant OER activity with a Tafel slope of 63.8 mV/decade and an overpotential at 541 mV for 50 mA/cm2. In the case of the glassy carbon electrodes, a Tafel slope of 109.9 mV/decade and an overpotential of 548 mV for 10 mA/cm2 is recorded for the catalyst. This paper outlines an interesting approach to synthesize cobalt oxide for OER through a slow decomposition of a precatalyst.

In Situ Synthesis of Manganese Oxide as an Oxygen-Evolving Catalyst: A New Strategy.

All studies on oxygen-evolution reaction by Mn oxides in the presence of cerium(IV) ammonium nitrate (CAN) have been so far carried out by synthesizing Mn oxides in the first step. And then, followed by the investigation of the Mn oxides in the presence of oxidants for oxygen-evolution reaction (OER). This paper presents a case study of a new and promising strategy for in situ catalyst synthesis by the adding MnII to either CAN or KMnO4 /CAN solution, resulting in the formation of Mn-based catalysts for OER. The catalysts were characterized by scanning electron microscopy, energy-dispersive spectroscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy. Both compounds contained nano-sized particles that catalyzed OER in the presence of CAN. The turnover frequencies for both catalysts were 0.02 (mmol O 2 /molMn ⋅s).

Water oxidation by Ferritin: A semi-natural electrode.

Ferritin is a protein (ca. 12 nm) with a central pocket of 6 nm diameter, and hydrated iron oxide stored in this central cavity of this protein. The protein shell has a complicated structure with 24 subunits. Transmission electron microscopy images of ferritin showed nanosized iron oxides (ca. 4-6 nm) in the protein structure. In high-resolution transmission electron microscopy images of the iron core, d-spacings of 2.5-2.6 Å were observed, which is corresponded to d-spacings of ferrihydrite crystal structure. Our experiments showed that at pH 11, the modified electrode by this biomolecule is active for water oxidation (turnover frequency: 0.001 s-1 at 1.7 V). Using affected by bacteria, we showed that Fe ions in the structure of ferritin are critical for water oxidation.

Effects of Two Types of Human Cells on Outgrowth of Human Glioma in Rats.

AIM: Glioblastoma multiforme (GBM) is one of the malignant brain tumors that occur most frequently. Despite advances in therapy techniques, the cure of GBM is a major concern. Accordingly, there is a lot of interest in devising novel approaches, such as stem cell therapy, to treat patients with GBM. The aim of this study was to investigate the effects of human bone marrow stem (BMS) cells as well as human olfactory ensheathing cells (OECs) on the outgrowth of U87 glioma in rats. MATERIAL AND METHODS: OECs and BMS cells were obtained from volunteers. After verification of the stem cell type by flow cytometry and immunocytochemistry (ICC), cells were labeled and injected into human glioma-bearing rats. Magnetic resonance imaging (MRI), Hematoxylin and Eosin (H&E), and Immunohistochemistry (IHC) were utilized to assess the properties of the groups. RESULTS: We found extensive migration and homing of the OECs and BMS cells towards the tumor area. H&E and IHC staining indicated that the grafted OECs survived and prevented the development of glioma. BMS cells supported proliferation and new vessel formation, and metastasis in glioma tissue. CONCLUSION: OECs and BMS cells can pass the blood brain barrier and reach the glioma mass. Therefore, this approach can be a potentially powerful method for the delivery of therapeutic agents to malignant brain tumors. In addition, these cells may be genetically modified in order to specifically express tumor-suppressive factors.

Induction of Human Glioma Tumor in Sprague-Dawley Rats with Intact Immune System.

AIM: Glioblastoma (GBM) is an aggressive brain tumor in humans. The median survival rate of patients is one year after the diagnosis. So, development of an animal model is necessary for the advances in the research treatment of GBM. The aim of this study was to investigate the capability of human glioma cells in inducing glioma tumors in rats with intact immune system. MATERIAL AND METHODS: U87 cells were implanted in the frontal lobe of rats without suppressing the immune system. We used magnetic resonance imaging (MRI), Hematoxylin-Eosin (H&E) and Immunohistochemical (IHC) staining to assess characteristics of tumor. RESULTS: At the 10th and 14th days of tumor inoculation, MRI images contained the tumor areas in the brain. All tumor-bearing rats developed tumors. The rats retained the morphology and histological characteristics of human glioma. Animals mimic GBM characteristics, such as mitotic activity, invasion, neovascularization, necrosis and pseudopalisading cells. IHC staining revealed tumor growth and progression in the tumor-bearing rats. CONCLUSION: This model is a standard system for studying the tumor phenotype, genotype, and for evaluating the efficacy of anti-cancer agents. It is a reliable, simple, inexpensive, and easily reproducible model, which may be a way for pre-clinical studies.

Evaluation of serological tests using A60 antigen for diagnosis of tuberculosis.

Identification of acid-fast bacilli (AFB) in sputum or tissue samples is among definite diagnostic methods of tuberculosis. However, this method of diagnosis is restricted by certain limitations. Serologic diagnosis of tuberculosis (TB) has been used for a long time. The aim of this study was to determine the sensitivity and, specificity of Antigen 60 (A60) IgG, IgA, IgM test results in TB diagnosis. Mycobacterial A60-based ELISA was used to measure specific IgA, IgM and IgG antibodies in the sera of 127 adult TB patients (consisted of 74 pulmonary and 53 extra-pulmonary cases), and 95 controls (46 healthy volunteers and 49 patients with various acute or chronic diseases other than tuberculosis). Data from A60 IgG-based ELISA, chest radiography, AFB culture and pathologic evaluation for AFB were obtained .The cutoff value of A60 IgG, IgA and IgM were chosen according to a receiver operating characteristic (ROC) analysis. The sensitivity, specificity and positive likelihood ratio were determined. The mean levels of IgG, IgA and IgM were significantly higher in patients with pulmonary tuberculosis when compared with control groups. Sensitivity of IgG test was 54.3 %, while the specificity was 84.2%. The IgA test showed a sensitivity of 70.1% with a specificity of 80 %. Combination of the IgG and IgA tests showed a total sensitivity of 45.7 % and a specificity of 94.7% and the positive likelihood ratio of 8.62. Chosen cutoff values of IgG, IgA, and IgM sets were 285,265 and 0.9 ELISA units respectively. Our study results showed a good specificity (94.7%) and a reasonable positive likelihood ratio (8.62) of the test when combined IgA and IgG with new cutoff points were considered on diagnosis of tuberculosis in adult patients. Combined use of both IgG and IgA tests results allows an increased accuracy in diagnostic of tuberculosis.

Subphrenic abscess and recurring focal lesions due to tuberculosis in a patient with IgA deficiency.

Subdiaphragmatic abscess has not yet been reported as a manifestation of tuberculosis. We report an IgA deficient patient with recurrent episodes of unusual extrapulmonary manifestations of tuberculosis including subdiaphragmatic abscesses and metacarpophalangeal osteomyelitis that was improved each time with antituberculosis drugs. There was not any resistance to the drugs used against mycobacterium despite repeated courses of antituberculosis regimens. In such recurrent cases, one should rule out any immunodeficiency states.