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Seethalakshmi Viswanathan Naveen Chawla Anil D’Cruz Shubhada V. Kane 《Head and neck pathology》2007,1(2):169-172
Histoplasmosis is a rarely reported deep mycotic infection in the Indian context. Oral or oropharyngeal manifestation can
occur as an isolated symptom or as part of a disseminated process associated with immunosuppression especially with HIV and
diabetes. Five cases of head and neck histoplasmosis accrued over 6 years in a tertiary referral cancer institute were reviewed.
All these patients presented clinically as cancer. In three patients, the marked pseudoepitheliomatous hyperplasia led to
a mistaken biopsy diagnosis of malignancy following which definitive surgical treatment was performed. The subsequent excision
revealed typical features of histoplasmosis. Isolated oral presentation of histoplasmosis can mimic malignancy both clinically
as well as pathologically, leading to potentially disastrous consequences. A high index of suspicion in those with overt or
hidden immunosuppression and a deep wedge biopsy to demonstrate the organisms in the subepithelial tissue is recommended.
This work has been presented in the “Slide seminar on Infections and Infestations” in the IAP-ID pre conference CME in APCON
2006. 相似文献
4.
Varadharaj S Watkins T Cardounel AJ Garcia JG Zweier JL Kuppusamy P Natarajan V Parinandi NL 《Antioxidants & redox signaling》2005,7(1-2):287-300
Recent clinical trials have shown that vitamin C, at pharmacological concentrations (milligram to approximately gram), upon infusion into circulation, modulates vasodilation and vascular tone in humans. This also results in the elevated concentrations of vitamin C in circulation in the millimolar range. Here, it was hypothesized that vitamin C at pharmacological concentrations (millimolar) would induce oxidative stress and cause loss of redox-dependent cell viability in vascular endothelial cells (ECs). To test the hypothesis, bovine lung microvascular ECs (BLMVECs) in monolayer cultures were exposed to vitamin C (0-10 mM) for different time periods (0-2 h). Electron paramagnetic resonance spectroscopy revealed the intracellular formation of ascorbate free radical in a dose- and time-dependent fashion. Vitamin C also induced formation of intracellular reactive oxygen species in a dose-dependent fashion. It was observed that vitamin C induced morphological alterations and loss of cell viability in a dose- and time-dependent fashion, as measured by light microscopy and Alamar Blue redox cell viability assay, respectively. Vitamin C analogues failed to induce such changes. Vitamin C depleted cellular GSH levels in a dose-dependent fashion, suggesting that vitamin C altered thiol-redox status in BLMVECs. Antioxidants, intracellular iron chelator, and catalase protected cells against vitamin C-induced loss of redox-dependent cell viability, confirming the role of hydrogen peroxide and iron during redox cycling of vitamin C. These results, for the first time in detail, established that vitamin C at pharmacological doses induced oxidative stress and loss of redox-dependent cell viability in microvascular ECs. 相似文献
5.
Dendritic cells and autoimmunity 总被引:7,自引:0,他引:7
Bayry J Thirion M Delignat S Misra N Lacroix-Desmazes S Kazatchkine MD Kaveri SV 《Autoimmunity reviews》2004,3(3):183-187
Dendritic cells (DC) are professional antigen-presenting cells that are specialized in the uptake of antigens and their transport from peripheral tissues to the lymphoid organs. Because of their capacity to stimulate naive T cells, DC have a central role in the initiation of primary immune responses and are considered promising tools and targets for immunotherapy. Emerging data suggest a role for DC in initiating autoimmune attacks. Direct analysis of DC phenotypes and DC-T-cell interactions in rodent and human autoimmune diseases should shed light on how pathogenesis occurs, and suggest novel avenues of treatment aimed at alleviating deviant DC function. 相似文献
6.
Mary Richardson Liying Liu Lauren Dunphy David Wong Yunming Sun Kasinath Viswanathan Gurmit Singh Alexandra Lucas 《Cardiovascular pathology》2007,16(4):191-202
BACKGROUND: Angiogenesis is a critical factor in the development of malignant tumors, in arthritic joints, and in cardiovascular disease. In cardiovascular disease, angiogenesis is recognised both as a potential therapy and as a complicating factor in atherosclerotic plaque rupture and thrombotic obstruction. Serine proteases regulate thrombosis, inflammation, and cell invasion, events that trigger various stages of angiogenesis and are in turn regulated by inhibitors, termed serpins. Serp-1 is a secreted anti-inflammatory viral serpin that profoundly inhibits early mononuclear cell invasion, and the development of atherosclerosis, transplant vasculopathy, and arthritis in a range of animal models. METHODS: The capacity of Serp-1 to alter angiogenesis was evaluated in the chicken chorioallantoic membrane (CAM) model using morphometric analysis of vascular changes and RT-PCR to explore alterations in gene expression. RESULTS: Serp-1 inhibited endogenous angiogenesis in a dose-dependent manner, with associated altered expression of laminin and vascular endothelial growth factor (VEGF). Serp-1 was ineffective in CAMs no longer in the rapid growth phase. Similar inhibition of angiogenesis was detected after inhibition of VEGF, but not after treatment with the inactivated reactive center loop mutant of Serp-1. CONCLUSIONS: The angiogenic process can be controlled using Serp-1, an anti-inflammatory agent that is effective at low concentrations with rapid reversibility, targets endothelial cells, and reduces the availability of VEGF. These properties may be especially important in cardiovascular disease, reducing plaque destabilization. It is likely that the anti-angiogenic activity of Serp-1 contributes to the observed anti-inflammatory and anti-atherogenic actions with potential importance in this therapeutic setting. 相似文献
7.
Learning increases stimulus salience in anterior inferior temporal cortex of the macaque. 总被引:5,自引:0,他引:5
With experience, an object can become behaviorally relevant and thereby quickly attract our interest when presented in a visual scene. A likely site of these learning effects is anterior inferior temporal (aIT) cortex, where neurons are thought to participate in the filtering of irrelevant information out of complex visual displays. We trained monkeys to saccade consistently to one of two pictures in an array, in return for a reward. The array was constructed by pairing two stimuli, one of which elicited a good response from the cell when presented alone ("good" stimulus) and the other of which elicited a poor response ("poor" stimulus). The activity of aIT cells was recorded while monkeys learned to saccade to either the good or poor stimulus in the array. We found that neuronal responses to the array were greater (before the saccade occurred) when training reinforced a saccade to the good stimulus than when training reinforced a saccade to the poor stimulus. This difference was not present on incorrect trials, i.e., when saccades to the incorrect stimulus were made. Thus the difference in activity was correlated with performance. The response difference grew over the course of the recording session, in parallel with the improvement in performance. The response difference was not preceded by a difference in the baseline activity of the cells, unlike what was found in studies of cued visual search and working memory in aIT cortex. Furthermore, we found similar effects in a version of the task in which any of 10 possible pairs of stimuli, prelearned before the recording session, could appear on a given trial, thereby precluding a working memory strategy. The results suggest that increasing the behavioral significance of a stimulus through training alters the neural representation of that stimulus in aIT cortex. As a result, neurons responding to features of the relevant stimulus may suppress neurons responding to features of irrelevant stimuli. 相似文献
8.
Emergence of a nephropathogenic avian infectious bronchitis virus with a novel genotype in India 总被引:4,自引:0,他引:4
Bayry J Goudar MS Nighot PK Kshirsagar SG Ladman BS Gelb J Ghalsasi GR Kolte GN 《Journal of clinical microbiology》2005,43(2):916-918
We describe the emergence of a nephropathogenic avian infectious bronchitis virus (IBV) with a novel genotype in India. The Indian IBV isolate exhibited a relatively high degree of sequence divergence with reference strains. The highest homology was observed with strain 6/82 (68%) and the least homology with strain Mex/1765/99 (34.3%). 相似文献
9.
Ma Yuan Sajeev Gautam VanderWeele Tyler J. Viswanathan Anand Sigurdsson Sigurdur Eiriksdottir Gudny Aspelund Thor Betensky Rebecca A. Grodstein Francine Hofman Albert Gudnason Vilmundur Launer Lenore Blacker Deborah 《European journal of epidemiology》2022,37(6):591-601
European Journal of Epidemiology - The apolipoprotein E allele 4 (APOE-ε4) is established as a major genetic risk factor for cognitive decline and late-onset Alzheimer’s disease.... 相似文献