Identification Of Novel Genes Involved In Azole Resistance And Sequence Analysis Of Known Resistance Genes In Candida Tropicalis

Opportunistic fungal infections resistant to antifungal agents have been increasingly documented in recent years and their fkequency will likely continue to increase. This phenomenon appears due to extensive use of antifungal agents to treat fungal infections especially candidiasis in irnmunocompromised patients. In this project, the molecular alterations in Candida tropicalis azole-resistant strain which may have contributed to the development of resistance against fluconazole have been investigated and potential drug targets have been identified. The differential gene expression profiles of a C-tropicalis resistant clinical strain, a C.fropicalis ATCC 750 induced-resistance strain and a Cadidla h e i inherent resistant strain were compared with a Candida tropicalis ATCC 750 susceptible strain via Differential Display Reverse Transcription Polymerase Chain Reaction. One hundred and six transcripts were found differentially displayed whereby 63 were up-regulated; three were down-regulated aMi 40 were non-expressed in the susceptible strain. Functional study of up-regulated transcripts in the resistant strain revealed that these transcripts were involved in cell wall maintenance (15%), transport function (12949, iii stress response (100/o), cell adherem (lo%)), cell defense (7%), morphogenesis (5%) and other functions (29%), whereby, 12% of the over-expressed transcripts are previously uncharacterized hypothetical protein. From our study, we found that other than ATP-binding cassette transporter, hexose transporter and KpsM (polysialic acid transporter) might play an important role in fluconazole drug efflux in C. tropicalis resistant strain. In developing fluconmole resistance, the C. tropicalis strain, is likely to increase the cell wall integrity and become more virulent by changing its gene regulation. Consistent with previous finding, we also - found that ADHl (alcohol dehydrogenase) was overexpressed in the resistant strain. We suggest that ADHl might be a potential novel drug target. In the sequence analysis of known resistance genes, 5 and 2 point mutations were reported in ERG11 (Lanosterol Demethylase) and CDRI (Candida Drug Resistance 1) of the clinical resistant strain, respectively. The point mutations were T867C, G1552A, T1555C, G1557T and G2016A in ERGII; C251A and A252C in CDRI. However, the contribution of these mutations in the activation of trans-regulatory factors that may thus result in up-regulation of mole-resistant transporter genes is still unknown

Quaternized wood as sorbent for hexavalent chromium

The potential of quaternized wood (QW) chips in removing hexavalent chromium from synthetic solution and chrome waste under both batch and continuous-flow conditions was investigated. Sorption was found to be dependent on pH, metal concentration, and temperature. QW chips provide higher sorption capacity and wider pH range compared with untreated wood chips. The equilibrium data could be fitted into the Langmuir isotherm model, and maximum sorption capacities were calculated to be 27.03 and 25.77 mg/g in synthetic chromate solution and chrome waste, respectively. The presence of sulfate in high concentration appeared to suppress the uptake of chromium by QW chips. Column studies showed that bed depth influenced the breakthrough time greatly whereas flow rate of influent had little effect on its sorption on the column

Interactive virtual indoor navigation system using visual recognition and pedestrian dead reckoning techniques

Finding a destination in an unfamiliar indoor environment requires cumbersome effort to refer to a physical floor plan or directory to locate the intended destination. With the advancements of mobile technologies, a navigational system using mobile computing devices such as mobile phone or tablet could aid users in locating the desired destination with ease. This paper presented an interactive virtual indoor navigation system which is developed for Sunway University campus. In order to provide an interactive and context-sensitive navigation platform, a hybrid solution has been proposed by blending the sensor capabilities on the mobile devices to work in an indoor environment. These sensors include utilizing the built-in accelerometer, compass and camera capabilities to create an interactive content of indoor navigation system using visual recognition and pedestrian dead reckoning for Augmented Reality (AR). Furthermore, user satisfaction and feedback survey have been collected for further improvement the proposed solution

Removal of reactive dyes by quaternized coconut husk

Coconut husk modified through the use of N-(3-chloro-2-hydroxypropyl)- trimethylammonium chloride was evaluated for its ability to remove reactive dyes from aqueous solution. Sorption of dyes was pH dependent and favorable sorption occurred at low pH. In contrast, natural coconut husk showed very little uptake of these reactive dyes. The maximum sorption capacities of the modified coconut husks for Reactive Blue 2, Reactive Yellow 2, Reactive Orange 16 and Reactive Blue 4 were 128.9, 182.2, 254.5 and 423.7 mg/g respectively. Column experiments using textile effluent showed that the reactive and disperse dyes in the effluent could be successfully removed

Effect of car exhausts on lead contamination in vegetables grown adjacent to Kuala Lumpur - Ceras Highway

It has already been established from studies over a wide area of Kuala Lumpur that lead contamination in grass adjacent to heavy-traffic roads is hazardous to grazing cattle if local forage grass is the only source of food (Low, Lee and Arshad, 1979). In Kuala Lumpur, a number of vegetable farms are located near heavy-traffic roads and contamination of lead caused by car exhausts on these vegetables has not been reported. This paper reports the levels of lead in leafy vegetables and their supporting soils in two locations. The first was a commercial vegetable farm some 50 m from the Kuala Lumpur - Ceras Highway with heavy tra/fic density. The second was a domestic garden located on the Universiti Pertanian Malaysia campus where the flow of vehicles is generally low. In these areas deposition oflead, if any, on vegetables comes almost exclusively from automobile exhausts. There is no other known source of lead contamination in these areas

Quaternized rice husk as sorbent for reactive dyes

A study on the sorption of hydrolyzed Reactive Blue 2 by quaternized rice husk showed that the binding capacity of the sorbent was not suppressed by dyebath conditions of high concentration of electrolytes. Its sorption capacity decreased with increasing concentration of NaOH. Complete regeneration of dye-coated quaternized rice husk was not possible under base treatment, suggesting chemisorption of dye molecules on the sorbent material. The physical stability of the quaternized rice husk was examined by treating it with various concentrations of NaOH solution. Results showed that no dissolution of sorbent occurred, even in 1 M NaOH solution

Australian Dementia Research: current status, future directions?

Important research initiatives have been taken in the last few years under the Dementia Initiative – making Dementia National Health Priority including the establishment of three new Dementia Collaborative Research Centres and additional funding for dementia research grants