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U. C. Srivastava I. D. Sakal R. C. Maurya 《Proceedings of the National Academy of Sciences, India. Section B.》2012,82(2):307-316
The present study, based on neurohistological techniques (Golgi impregnation), focuses on the morphological and numerical changes in the dendritic spines of neuronal classes of the cerebral cortex in Calotes versicolor. The cerebral cortex in reptiles occupies the roof of the cerebral hemisphere and is divided into four regions viz. medial, dorsomedial, dorsal and lateral cortex. Using different characteristics such as criteria of location, dendritic tree pattern, dendritic spine covering and soma shape different neuronal types have been distinguished in the cell layer-II of medial, dorsomedial, dorsal and lateral cortex. The dendritic diameter, spine length and diameter of spine head show almost uniform pattern in all cortical regions except being slightly higher in case of the neurons of dorsomedial cortex. The multipolar and pyramidal neurons show higher dendritic diameter, spine length, spine head diameter and dendritic spine density in comparison to other neurons. The density of these neurons acts as the indicator of high or low activity of a particular region. 相似文献
13.
Vikas Maurya Uday Aditya Gupta Ravindra K. Dewan Sudhir Jain Ashok Shah 《Archivos de bronconeumologia》2013,49(1):31-34
Spontaneous, complete resolution of inflammatory pseudotumour (IPT) of lungs is exceptionally rare. A 44-year-old male was referred for evaluation for «non resolving pneumonitis». He had cough and minimal expectoration for 5 months, chest pain, haemoptysis and fever for a fortnight. Computed tomography of thorax (CT-thorax) confirmed the presence of a homogenous mass with irregular borders in right middle lobe with areas of breakdown and air bronchogram. Transbronchial lung biopsy was suggestive of «plasma cell granuloma». Thoracotomy disclosed a hard mass in right middle lobe adherent to lower lobe, chest wall and mediastinum which could not be removed. A wedge biopsy confirmed IPT. Chest radiograph after 4 weeks revealed significant resolution. CT-thorax a year later showed fibrotic scar. Till date, there are only five reports documenting 6 patients with spontaneous resolution of IPT of lungs and in 4 this occurred within 3 months of an invasive diagnostic intervention. 相似文献
14.
A. Sharma S. Singh R. Tewari V.P. Bhatt J. Sharma I.K. Maurya 《Journal de Mycologie Médicale》2018,28(3):443-451
In the present study, we have evaluated the antifungal activity of the seed, root and leaf of Paeonia emodi (commonly known as Himalayan peony) in four common solvents (acetone, chloroform, methanol and water) against six fungal strains. The methanolic seed extract (MSE) showed promising antifungal activity against Candida albicans (6.25 mg/mL), Candida glabrata (3.12 mg/mL) and Candida parapsilosis (12.50 mg/mL) among all the fungal strains tested. Combination of the MSE with the well-known commercial antifungal drugs amphotericin B (Amp B), nystatin (NYS) and fluconazole (FLC) resulted in the killing of C. glabrata at non-inhibitory concentrations, i.e., 0.35 μg/mL for Amp B, 0.55 μg/mL for NYS and 1.19 μg/mL for FLC. Notably, MSE caused cell wall damage of C. glabrata cells, as confirmed by confocal microscopy, flowcytometry and scanning electron microscopy (SEM). The MSE was fractionated by thin layer chromatography (TLC). TLC-bioautography was used to determine the active compounds present in the MSE. Column chromatography was used to separate the potential active compounds from the MSE. Furthermore, gas chromatography-mass spectrometry (GC-MS) andfourier-transform infrared spectroscopy (FTIR) were used to identify the phytocomponents of the MSE. These experiments revealed 13-docosenamide/9-octadecenamide/trans-13-docosenamide (89.70%) as being the predominant compound using a chloroform/methanol solvent system for the separation. Interestingly, the MSE also exhibited less significant cytotoxicity at the minimum inhibitory concentration (MIC) against mammalian cells (HeLa and HEK293). This study suggests that the MSE of P. emodi can be used for the treatment of C. glabrata infection. 相似文献
15.
Anorexia nervosa (AN) is a serious life-threatening illness that typically has its onset during the adolescent years. Evidence regarding the optimal treatment of AN in children and teenagers is growing; however, much remains unknown. Although current treatment approaches vary in Canada and elsewhere, the evidence to date indicates that family-based treatment (FBT) is the most effective treatment for children and teenagers with AN. A key component of the FBT model is that the parents are given the responsibility to return their child to physical health and ensure full weight restoration. An understanding of the basic principles and philosophy underlying FBT allows the physician to initiate elements of this evidence-based intervention to young patients with AN and their families. 相似文献
16.
Role of extracellular adenosine triphosphate in the cytotoxic T- lymphocyte-mediated lysis of antigen presenting cells 总被引:4,自引:0,他引:4
The lysis of antigen presenting cells (APCs) by cytotoxic T lymphocytes (CTLs) may be one mechanism whereby an immune response is downregulated by Staphylococcus superantigens. Disappearance of monocytes/macrophages from staphylococcal enterotoxin A (SEA)-activated peripheral blood mononuclear cell (PBMC) cultures, but not from control PBMC cultures was seen by flow cytometry. Recently, adenosine triphosphate (ATP) has been described as an effector molecule in CTL-mediated lysis of some murine tumor target cells. We have also shown that ATP caused the lysis of human macrophages, and that treatment of cells with interferon gamma (IFN gamma) rendered macrophages significantly more sensitive to ATP than untreated cells. To show that this purine nucleotide may play a role in modulating the immune system, we generated human CTLs that were stimulated with SEA, and used them as effector cells against SEA-pulsed autologous macrophages. CTLs were found to specifically lyse SEA-pulsed macrophages, while control, unpulsed, macrophages were unaffected. The addition of hexokinase, an enzyme that hydrolyzes ATP, significantly abrogated the killing of SEA-pulsed cells during the assay. In examining the mechanism of cytotoxicity, electron microscopy showed that macrophages incubated with both ATP and CTLs underwent necrosis, rather than apoptosis. From these results, it is suggested that ATP is released from CTLs during antigen presentation, and that IFN gamma- activated macrophages, which are inherently more sensitive to this mediator, are readily lysed and therefore removed from circulation, thus downregulating an immune response. 相似文献
17.
Human monocytes express interleukin-2 receptor beta (IL-2R beta) constitutively; however, the function of these receptors has not been fully delineated. We discovered that IL-2R beta directs two biologic activities in human monocytes, the release of granulocyte-macrophage colony-stimulating factor (GM-CSF) and increased susceptibility to lysis by lymphokine-activated killer cells (LAK) cells. Human monocytes were purified from peripheral blood mononuclear cells by plastic adherence and anti-CD2 plus complement lysis. By a 5-hour 51Cr-release assay, monocytes cultured in IL-2 were found to gain increasing susceptibility to LAK cells with time and this effect was dose dependent. Maximal susceptibility was obtained with a 4-day culture in 1,000 U/mL of IL-2. Monocytes were also found to release GM-CSF in response to IL-2 using a CSF-dependent cell line, Mo7e. Because IL-2- induced GM-CSF release coincides with LAK lysis of IL-2-cultured monocytes, we treated monocytes with anti-GM-CSF and anti-IL-2R beta to determine whether GM-CSF release and LAK susceptibility were dependent or independent events. We found that both phenomena were inhibited by either antibody. Therefore, we conclude that IL-2-induced release of GM- CSF is mediated by IL-2R beta, which then acts to modulate the susceptibility of monocytes to lysis by LAK cells. 相似文献
18.
Thrombospondin mediates the cytoadherence of Plasmodium falciparum- infected red cells to vascular endothelium in shear flow conditions 总被引:3,自引:0,他引:3
Rock EP; Roth EF Jr; Rojas-Corona RR; Sherwood JA; Nagel RL; Howard RJ; Kaul DK 《Blood》1988,71(1):71-75
Cerebral malaria is thought to involve specific attachment of Plasmodium falciparum-infected knobby red cells to venular endothelium. The nature of surface ligands on host endothelial cells that may mediate cytoadherence is poorly understood. We have investigated the effects of soluble thrombospondin, rabbit antiserum raised against thrombospondin, and human immune serum on cytoadherence of parasitized erythrocytes in ex vivo mesocecum vasculature. Preincubation of infected red cells with soluble thrombospondin or human immune serum inhibits binding of infected red cells to rat venular endothelium. Infusion of the microcirculatory preparation with rabbit antithrombospondin antibodies before perfusion of parasitized erythrocytes also resulted in decreased cytoadherence. In addition, incubation of infected cells with human immune sera obtained from malaria patients significantly inhibited the observed cytoadherence. Our results indicate that thrombospondin mediates binding of infected red cells to venular endothelium and may thus be involved in the pathogenesis of cerebral malaria. 相似文献
19.
Saurabh Shukla Anil Kumar Tripathi Shailendra Prasad Verma Deependra Kumar Yadav R. K. Tripathi Shweta Maurya Nidhi Awasthi 《Indian journal of hematology & blood transfusion》2021,37(2):210
Aplastic anemia (AA) is an immune-mediated disorder in which hematopoietic stem and progenitor cells are targeted by a number of cellular and molecular pathways. This case control study aims to investigate the association of interleukin-1beta (IL-1β) gene polymorphisms, (IL-1β-31, IL-1β-511 and IL-1β-3954) and their plasma levels with acquired AA. Genotyping was done by Restricted Fragment Length Polymorphism (PCR–RFLP) method and IL-1β plasma levels were evaluated in peripheral blood using ELISA. Increased level of IL-1β was reported to be significant in cases as compared to controls. The susceptibility of developing AA was higher in the cases for IL-1β-3954 genotype. IL-1β-511 genotype showed significant association with the severity groups of AA. No significant association was noticed in responder versus non-responder group. Plasma level of IL-1β gene was found to be significantly higher in severe and very-severe group of AA versus control group. Our findings suggest that IL-1β gene and its genotypes might be involved in the pathophysiology of AA and play a central role in the etiopathogenesis of AA. 相似文献
20.
Several studies conducted on chicken have shown that a single stress exposure may impair or improve memory as well as learning processes. However, to date, stress effects on neuronal morphology are poorly investigated wherefore it was of interest to evaluate this further in chicks. Thus, the present study aims to investigate the role of single acute stress (AS) of 24 h food and water deprivation in neuronal plasticity in terms of spine density of the corticoid complex (CC) in 15-day-old chick, Gallus domesticus, by using three neurohistological techniques: Cresyl Violet, Golgi Colonnier, and Golgi Cox technique. The dorsolateral surface of the cerebral hemisphere is occupied by CC which can be differentiated into two subfields: an intermediate corticoid (CI) subfield (arranged in layers) and a dorsolateral corticoid (CDL) subfield. Based on different criteria such as soma shape, dendritic branching pattern, and dendritic spine density, two main moderately spinous groups of neuronal cells were observed in the CC, namely, projection neurons (comprising of multipolar and pyramidal neurons) and stellate neurons. In the present study, the stellate neurons have shown a significant decrease as well as an increase in their spine density in both CI and CDL subfields, whereas the multipolar neurons had shown a significant increase in their spine density in the CDL region only. The present study shows that AS induces neuronal plasticity in terms of spine density in both CI and CDL neurons. The morphological changes in the form of decreased dendritic branches due to stress have been observed in the CI region in comparison to CDL region, which could be linked to more effect of stress in this region. The avian CDL corresponds to the entorhinal cortex of mammals on the basis of neuronal morphology and bidirectional connections between adjacent areas. The projection neurons increase their branches and also their spine number to cope with the stress effects, while the stellate neurons show contrasting effect in their spine density. Therefore, this study will establish that slight modifications in natural stimuli or environmental changes faced by the animal may affect their dorsolateral forebrain which shows neuronal plasticity that help in the development of an adaptive capacity of the animal to survive under changing environmental conditions. 相似文献