76 research outputs found
Epidemiological profile of fungal keratitis in urban population of West Bengal, India
No full textBackground : Corneal diseases are one of the major causes of visual loss and blindness, second only to cataract. Amongst corneal diseases, microbial keratitis is a major blinding disease. In some countries, fungal keratitis accounts for almost 50% of patients with culture-proven microbial keratitis.
Aim : This study was conducted to determine the epidemiological characteristics of fungal keratitis in an urban population of West Bengal and identify the specific pathogenic organisms.
Methods : The charts of patients with microbial keratitis who attended the Cornea Services of Priyamvada Birla Aravind Eye Hospital from January to December 2008 were retrospectively reviewed. Records of patients with 10% KOH mount and culture positive fungal keratitis were analyzed for epidemiological features, laboratory findings and treatment outcomes.
Results : Of the 289 patients of microbial keratitis included in the study, 110 patients (38.06%) were diagnosed with fungal keratitis (10% KOH mount positive). Of the 110 patients, 74 (67.27%) fitted the study inclusion criteria (10% KOH mount and culture positive). Forty five of 74 patients (60.81%) in the study group were in the older age group (>50 years). Ocular trauma in 35 cases (47.29%) was identified as a high risk factor and vegetative injuries in 17 cases (22.97%) were identified as a significant cause for fungal keratitis. Maximum organism source was from corneal scrapings in 41 cases (55%). The predominant fungal species isolated was Aspergillus sp (55.40%) followed by Candida albicans 14 cases (18.91%) and Fusarium sp. in 8 cases (10.81%). Agricultural activity related ocular trauma was the principal cause of mycotic keratitis and males were more commonly affected. Thirty of 74 cases (40.55%) of the culture positive patients healed with corneal scar formation with medical treatment whereas 44 cases (59.45%) required therapeutic keratoplasty.
Conclusion : Fungal keratitis is an important cause of microbial keratitis with injury to the cornea being a leading predisposing factor. Although Aspergillus sp. was implicated in most of the patients in our study population, Candida sp. were found in higher numbers than previously reported. Keratitis caused by filamentous fungi responds adequately to medical management. Therapeutic keratoplasty continues to remain an important treatment modality in infections with Candida sp. Early diagnosis with prompt identification of the pathogenic organism is mandatory to initiate appropriate therapy and thereby reduce morbidity
Rhodotorula mucilaginosa Keratitis: A rare fungus from Eastern India
No full textRhodotorula mucilaginosa rarely cause keratitis in immunocompromised individuals. A 30 year old male with history of minor trauma presented with cotton wool like stromal infiltration and hypopyon in left eye. Microbiological examination of corneal scraping showed fungal hyphae and yeast cells in direct smear. Molecular identification of the organism was performed which showed 100% homology with Rhodotorula mucilaginosa. Management of these cases is difficult often necessitating surgical procedures. However further reports are necessary to understand the disease and establish a treatment protocol
Development of Fullerene Modified Metal Oxide Thick Films for Moisture Sensing Application
No full textTrace moisture sensing capability of fullerene (C-60) modified nanoporous gamma-alumina (Al2O3) thick films has been presented here. Fullerene was added to create nano pore in aluminum secondary butoxide for preparation of gel tape cast thick films. One of the major advantages of using fullerene is to develop oriented nano pores (2-12 nm) throughout the ceramic thick films. The green thick films were crack free which was cast by gel tape casting process. The porosity and surface area were studied using field effect scanning electron microscope, atomic force microscope and Brunauer-Emmett-Teller. Gamma phase of alumina was also examined by X-ray diffraction analysis. The green thick films were sintered at 900 degrees C to obtain nanopore distribution through the surface of the thick films. Electrical characterization such as sensitivity, response, recovery and hysteresis were performed. There is no literature report on the detection of trace moisture sensor by fullerene assisted alumina sol gel tape cast process. This article explains the development of moisture sensor which can detect low range moisture (1-25 ppm) in different industrial application like gas industry, dielectric oil and drying of different food processing industry etc. (C) 2017 Elsevier Ltd. All rights reserved. Selection and/or Peer-review under responsibility of International Conference on Functional Nano-Materials, 2016
Development of Fullerene Modified Metal Oxide Thick Films for Moisture Sensing Application
No full textTrace moisture response property of thin film nano porous gama-Al2O3 for industrial application
No full textNano porous thin film γ-Al2O3 is prepared by sol-gel method by heat treating process at 5500C.The samples are made of various coating thickness and investigated as trace moisture sensor at room temperature within the range of –720C to –420C dew point (DP). It is found that at a particular coating thickness the sensitivity and response time are found to be suitable for commercial application. The capacitance change over the dew point (DP) range from –720C to –420C is found to be prominent for making a sensitive device
Effect of Porosity on the Response of Alumina Thick Films towards Moisture
No full textIn this work, porous thick films of α-Al2O3 and γ-Al2O3 ceramic materials have been investigated as moisture sensitive materials. The thick film of synthesized α-Al2O3 was sensitive to a wide range of relative humidity (10%-95%), while γ-Al2O3 thick film with controlled micro and nano porosity was found to be effective in the detection of low concentration moisture, viz.1-100 ppm. The tape casting of α-Al2O3 and gel casting of γ-Al2O3 were carried out using organic additives and pore former additives, respectively. Characterization of the synthesized materials was executed using X-ray diffraction, field emission scanning electron microscopy, atomic force microscope and Brunauer-Emmett-Teller surface area analysis. The important parameters like humidity sensitivity, response and recovery time which determine the efficiency of the thick film sensors were found to be influenced by the microstructure of the final films. Pore size distribution and surface area of the films were examined by Hg intrusion porosimetry and BET techniques as both of these properties play an important role in moisture sensing. The developed sensors exhibit significant sensitivity to moisture (humidity) and long time stability which are essential for device application. These sensors are applicable in various industrial and medical fields
- …
