Chemical Oxidative Polymerization of Methylene Blue: Reaction Mechanism and Aspects of Chain Structure

The kinetic regularities of the initial stage of chemical oxidative polymerization of methylene blue under the action of ammonium peroxodisulfate in an aqueous medium have been established by the method of potentiometry. It was shown that the methylene blue polymerization mechanism includes the stages of chain initiation and growth. It was found that the rate of the initial stage of the reaction obeys the kinetic equation of the first order with the activation energy 49 kJ × mol−1. Based on the proposed mechanism of oxidative polymerization of methylene blue and the data of MALDI, EPR, and IR spectroscopy methods, the structure of the polymethylene blue chain is proposed. It has been shown that polymethylene blue has a metallic luster, and its electrical conductivity is probably the result of conjugation over extended chain sections and the formation of charge transfer complexes. It was found that polymethylene blue is resistant to heating up to a temperature of 440 K and then enters into exothermic transformations without significant weight loss. When the temperature rises above 480 K, polymethylene blue is subject to endothermic degradation and retains 75% of its mass up to 1000 K.

Histochemical Assessment of Mucin-Secreting Cells from the Gastric Mucosa of Guinea Pigs

Stomach fragments from 3 guinea pigs were collected from the three regions: cardiac, fundic and pyloric, for histochemical investigations. The anatomical segments were processed by the classical method of inclusion in paraffin and the histological sections were stained with PAS reaction for highlighting the neutral mucins and the Alcian blue method for acid mucins. All the surface cells of the gastric mucosa and in the crypts were positive on the PAS reaction and negative in the case of the alcian blue reaction. This demonstrates that cells on the surface and in the crypts synthetize neutral mucins. In the case of the cardiac region glands, only a small number of cells were positive on the two histochemical reactions, which shows that the cardiac glands in guinea pig synthesize a very small amount of neutral and acidic mucins. There are no positive cells in neither reaction used in the fundic glands case, which shows that these glands do not synthesize mucins, neither neutral nor acidic content. The glands located in the pyloric region have cells in the deep half of the wall which were positive on both histochemical reactions, which shows that they synthesize both neutral mucins and acidic mucins.

Biología de las células madre mesenquimales y sus aplicaciones en medicina regenerativa

ResumenLas células madre mesenquimales (CMM) se pueden definir como células estromales mesenquimales multipotentes que proliferan in vitro y tienen una morfología similar a fibroblastos, forman colonias in vitro y pueden diferenciarse en osteoblastos, condrocitos y adipocitos, así como mantienen interacciones con el sistema inmune. Estas CMM pueden ser aisladas y expandidas en medio de cultivo debido a sus propiedades de adhesión al plástico del matraz de cultivo, diferenciación y proliferación in vitro. Se ha logrado aislar y mantener en cultivo CMM de articulaciones del quiridio de caballo, cuya subpoblación STRO-1 positiva mantenida en condiciones de hipoxia se diferencia por el linaje de condrocitos identificados por la reacción azul Alcian. Las propiedades inmunorreguladoras de las CMM causan la alteración de la proliferación y las funciones efectoras de la mayoría de las poblaciones celulares del sistema inmune, innato y adaptativo.Las características de diferenciación multilinaje y de inmunoregulación de las CMM está permitiendo su usoen medicina regenerativa; se estima que en los próximos 5 años el potencial de esta nueva estrategia terapéutica podrá visualizarse porque habrá muchos productos y protocolos de tratamiento basados en la medicina regenerativa. Palabras clave: células madre mesenquimales (CMM), multipotencia, inmunoregulación, linajes celulares, cultivo in vitro, proliferación AbstractMesenchymal stem cells (MSCs) can be defined as multipotent mesenchymal stromal cells that proliferate in vitro and have a fibroblast-like morphology and form in vitro colonies. They can distinguish into osteoblasts, chondrocytes, and adipocytes, as well as interact with the immune system. These MSCs can be isolated and expanded in culture medium due to their properties of adhesion to the culture flask plastic, differentiation, and proliferation in vitro. Isolation and CMM culture of joints of the horse chiridium has been achieved, whose subpopulation STRO-1 positive maintained in hypoxia conditions differs from chondrocyte lineage identified by the Alcian blue reaction. The immunoregulatory properties of MSCs cause alteration of the proliferation and effector functions of most cell populations of the immune, innate and adaptive system. The multilinear differentiation and immunoregulation characteristics of MSCs are allowing their use in regenerative medicine. It is estimated that in the next 5 years the potential of this new therapeutic strategycan be visualized because there will be many products and treatment protocols based on regenerative medicine. Keywords: mesenchymal stem cells (MSC), multipotency, immunoregulation, cell lineages, in vitro culture, proliferation.

Presence of Granular Ducts in Mandibular Gland in Rabbit

The present study focuses on the intralobular ducts present in rabbit mandibular gland, from a histological and histochemical point of view. We harvested mandibular gland samples from five rabbits (approximately six month old), which were paraffin embedded and subsequently stained for histological investigation with hematoxylin-eosin. PAS and Alcian blue reactions were used for histochemical assessment. Results show that mandibular gland in rabbit contains one type of acini, namely serous. Concerning the intralobular ducts, there were three types identified: intercalated, granular and striated. Granules present in the cytoplasm of the cells lining the granular ducts appear acidophilic on hematoxylin-eosin staining procedure. Histochemically, granular cells present a moderately PAS positive material (meaning they secrete neutral mucosubstances) and negative staining to Alcian blue reaction (no acid and sulfated mucosubstances were detected). We highlighted the presence of granular ducts in rabbit mandibular gland, which synthesize neutral mucosubstances according to the histochemical reactions applied.

Associating Serum Iron and Magnesium Levels in Hypertensive and Chronic Periodontitis Patients: Do They have a Link?

ABSTRACT Introduction Micronutrients have been extensively studied in recent years; of these magnesium and iron are essential for a variety of physiologic functions. Activation of neutrophils is an early effect of hypomagnesemia, which, in turn, causes periodontal tissue destruction. Since magnesium also influences blood pressure regulation by vascular tone and reactivity, its altered levels could contribute to the pathophysiology of hypertension. Iron plays a key role in the formation of reactive oxygen species that causes peroxidative damage to tissues. Aims and objectives The present study is designed to estimate the levels of serum iron and magnesium in healthy, chronic periodontitis patients with and without hypertension. Materials and methods This study includes 90 subjects, age ranging from 18 to 65 years. They were categorized into three groups as group I: 30 periodontally healthy, group II: 30 chronic periodontitis, and group III: 30 chronic periodontitis with hypertension. Serum magnesium levels were determined using the modified xylidyl blue reaction method and serum iron levels using ferrozine method without deproteinization via photometry. Results Biochemical parameters showed mean serum iron levels in chronic periodontitis (59.17) to be significantly reduced as compared with the control group (76.90) and slightly increased in the chronic periodontitis with hypertension group (69.63). Serum magnesium levels were found to be significantly lower in the hypertensive group as compared with the chronic periodontitis and control groups. Conclusion Iron and magnesium have a link in the pathophysiology of periodontitis. Serum iron and serum magnesium levels were closely linked to periodontitis and hypertension. How to cite this article Kalburgi NB, Koregol AC, Mary TJJ, Warad S, Annam T, Kataria N. Associating Serum Iron and Magnesium Levels in Hypertensive and Chronic Periodontitis Patients: Do They have a Link? J Health Sci Res 2017;8(2):61-65.

The Role of the Iron Stain in Assessing Intracranial Hemorrhage

The timing of the breakdown of red blood cells and organization of hemorrhage has significance in the catabolism of heme and the processing of iron, but also has a practical application in terms of assigning, or attempting to assign, a time course with respect to traumatic events (e.g. contusions and hemorrhages). Attempts to date contusions, however, have generally been unsuccessful by macroscopic observation, whereas the microscopic observations provide broad data but are also anatomically imprecise as a function of time. Intracranial lesions are of particular significance with respect to the timing of organizing hemorrhage given the acute, and often life-threatening nature of the hemorrhages, and the medicolegal investigation into potential crimes. Of concern is that the Prussian Blue reaction for iron, a relatively straightforward histochemical reaction that has been in use for over 150 years, is sometimes suggested as a diagnostic test for chronicity. Therefore, this study examined the utility of the Prussian Blue iron stain in living patients with intracranial hemorrhages and well-defined symptom onset, to test whether the presence of Prussian Blue reactivity could be correlated with chronicity. It was found that out of 12 cases with intracranial hemorrhage, eight cases showed at least focal iron reactivity. The duration from symptom onset to surgery in those eight cases ranged from < 24 hours to more than 3 days. Of those cases with no iron reactivity, the duration from symptom onset to surgery ranged from < 24 hours to six days. In conclusion, the Prussian Blue reaction was unreliable as an indicator of timing in intracranial hemorrhage. The use of the Prussian blue reaction as an independent indicator of chronicity is therefore not valid and can be misleading. Caution is indicated when employing iron staining for timing purposes, as its only use is to highlight, as opposed to identify, pre-existing lesions. With respect to brain lesions, the Prussian blue reaction should not be used in place of the clinical timing of the neurologic decline, or clinical data that is otherwise more accurate and less susceptible to false positive results.