123 research outputs found
Isolation of fungi from Sabah that produce Bioactive compounds which effect signal transduction
Filamentous micro-fungal strains were isolated from various environments in
Sabah especially from the soil of the rain forest.' Sabah with its unique natural
resources provides the means for the discovery of new micro-fungal strains with the
potential to produce novel bioactive secondary metabolite compounds which affect
signal transduction. This is the main focus of this research. A total of 364 fungal
strains were isolated. Extracts from the aerobic liquid fermentation of these fungal
strains were screened for inhibitory effect on Signal transduction of both yeast and
bacterial strains. In the course of this research, soil samples have been collected in
the expeditions that were carried out by this university to remote locations of Sabah.
These expeditions include the primary forest of the Imbak Valley, limestone hill forest
of Tabin Wildlife Reserve, the the lower montane heath forest forest of Maliau Basin
Conservation Area and the montane forest of Mount Trus Madi. The soil samples
were mostly collected from leaf litter under trees and other plants that were identified
to species or genus level. A number for fungal strains were also isolated from
explants and from fungal airborne spores of plates and in around the laboratory. The
characteristics of the micro-fungi strains on the PDA agar were observed and this
includes colour of the aerial and substrate mycelia, difussed pigmentation and growth
rate on the' PDA plates. Microscopic identification was done on the strains which
showed activity on screening tests performed. All the micro-fungal strains isolated
were grown in aerobic condition in liquid fermentation. It was these extracts that were
used for,the screening for specific molecular targets involve in signal transduction,
such as, serinelthreonine phosphatase, MAPK Kinase, MAP Kinase phosphatase,
Ras/Raf protein interaction, and serinelthreonine,kinase. All the screening systems
mention are base on the eukaryotic signalling pathways of yeast except for the
serinelthreonine kinase screen which is base on the prokaryotic signalling pathway of
Streptomyces griseus which shares high similarity with eukaryotic signalling pathway.
In this research, there were fungal strains which showed inhibitory effect to the
serinelthreonine phosphatase type 1 homolog, Glc7p especially the strains H9318
and H9307 from Maliau Basin. These two strains were latter found to inhibit
dephosphorylation of phosphorylase catalyse by the mammalian serineltheronine
phosphatase, Protein Phosphatase type 1 gam a (PP1y) as well. The effect on PP1y
as well as Glc7p is not supprising as both these protein shares more than 75%
homology in its catalytic domain. Three strains which showed positive activity in the
MAPK Kinase screening system are H9013, H9014 and H9019. No fungal strains
were found to be affecting the MAP Kinase Phosphatase (MSG 5) and the RaslRaf
protein interaction which would indicate a positive result. There were numerous
extracts from fungal strains which inhibit the growth of Streptomyces griseus and two
strains which showed potential to be inhibitors of serinelthreonine kinase (AfsK) of
Streptomyces griseus. These two strains were H9016 and H9123. There were also
two fungal strains H9341 and H9346 which showed toxicity in all the screens
performed except for the serineltheronine kinase test of S.griseus. This would
indicate these strains are toxic to at least Scharomycetes cerevisiae cells. The fungal
strains isolated .from soil and from other environment showed some specificity in the
types of strains isolated and the secondary metabolites produced. The microfungi
from Sabah proved to be prolific producers of diverse secondary metabolites which
effect signal transduction and growth of cell
Efficient feature-based image registration by mapping sparsified surfaces
With the advancement in the digital camera technology, the use of high resolution images and videos has been widespread in the modern society. In particular, image and video frame registration is frequently applied in computer graphics and film production. However, conventional registration approaches usually require long computational time for high resolution images and video frames. This hinders the application of the registration approaches in the modern industries. In this work, we first propose a new image representation method to accelerate the registration process by triangulating the images effectively. For each high resolution image or video frame, we compute an optimal coarse triangulation which captures the important features of the image. Then, we apply a surface registration algorithm to obtain a registration map which is used to compute the registration of the high resolution image. Experimental results suggest that our overall algorithm is efficient and capable to achieve a high compression rate while the accuracy of the registration is well retained when compared with the conventional grid-based approach. Also, the computational time of the registration is significantly reduced using our triangulation-based approach
Draft Genome Sequence of a Phytopathogenic Ganoderma sp. Strain That Causes Basal Stem Rot Disease on Oil Palm in Sabah, Malaysia
Basal stem rot (BSR) disease on Elaeis guineens is known to be caused by members of the pathogenic fungal genus Ganoderma, especially the species Ganoderma boninense. This species affects oil palm plantation in Sabah, Malaysia. The genome sequence (52.28 Mbp) will add to the representation of this genus, especially in regard to BSR disease
Molecular characteristics of infection and colonization isolates of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA)
Staphylococcus aureus is a gram-positive coccus that colonizes the skin and mucous membranes, particularly the anterior nares. Recently, community-acquired MRSA (CA-MRSA) has emerged as a cause of skin and soft-tissue infections in healthy individuals. These strains are sensitive to antimicrobials, carry genes for Panton-Valentine leukocidin (PVL) toxin, and feature the staphylococcal cassette chromosome mec (SCCmec) type IV or V. The suspected mode of transmission involves close contact with carriers, leading to skin or nasal colonization that results in subsequent active infection. This study was undertaken to determine the molecular characteristics of CA-MRSA isolates in children presenting with wound infections at Likas Hospital, Sabah, Malaysia, and the possible mode of transmission. The results showed that the majority of CA-MRSA infection isolates were from scalp abscesses (49%) in 1–5-year-old children (70%) in the Filipino (54%) community. The presence of the mec gene was detected in all isolates and the PVL virulence factor was found in 92% of the isolates. SCCmec typing revealed that 57% of the isolates were untypable, 35% harbored the SCCmecIVa element, and one each had SCCmecIVc, SCCmecV, or SCCmecII. Sixteen S. aureus strains were isolated from nasal swabs in 19 family members of index patients. Fourteen of these cultures were positive for catalase, coagulase, and DNAase. All of the colonization isolates carried the mecA gene and only a third were positive for the PVL toxin. SCCmec typing showed that 79% of the isolates were untypable and two had SCCmecIVa element and one had SCCmecV element. When five pairs of infection and colonizing isolates were compared by spa typing, only two pairs showed identical spa type with possible transmission between the patient and family contact. Further studies are necessary to establish CA-MRSA transmission by performing multiple-site cultures multiple times instead of one-time naresonly sample collection
A comparative transcriptomic analysis provides insights into the cold-adaptation mechanisms of a psychrophilic yeast, Glaciozyma antarctica PI12
Glaciozyma antarctica PI12, a psychrophilic yeast from Antarctica, grows well at low temperatures. However, it is not clear how it responds and adapts to cold and freeze stresses. Hence, this project was set out to determine the cold-adaptation strategies and mechanisms of G. antarctica PI12 using a transcriptomic analysis approach. G. antarctica PI12 cells, grown in rich medium at 12 °C, were exposed to freeze stress at 0 and − 12 °C for 6 h and 24 h. Their transcriptomes were sequenced and analyzed. A hundred and sixty-eight genes were differentially expressed. The yeast gene expression patterns were found to be dependent on the severity of the cold with more genes being differentially expressed at − 12 °C than at 0 °C. Glaciozyma antarctica PI12 was found to share some common adaptation strategies with other yeasts, Saccharomyces cerevisiae and Mrakia spp., but at the same time, found to have some of its own unique strategies and mechanisms. Among the unique mechanisms was the production of antifreeze protein to prevent ice-crystallization inside and outside the cell. In addition, several molecular chaperones, detoxifiers of reactive oxygen species (ROS), and transcription and translation genes were constitutively expressed in G. antarctica PI12 to enable the cells to endure the fluctuating freezing temperatures. Interestingly, G. antarctica PI12 used nitrite as an alternative terminal acceptor of electrons when the oxygen level was low to minimize disruption of energy production in the cell. These mechanisms coupled with several other common mechanisms ensured that G. antarctica PI12 adapted well to the cold temperatures
Noninterventional statistical comparison of BTS and CHEST guidelines for size and severity in primary pneumothorax.
Hilar rather than apical interpleural distance more accurately predicts need for intercostal chest drain insertion http://ow.ly/JvKFYThe study was funded by the East Anglian Thoracic Society. M.Z. Nikolić
is a Wellcome Trust PhD
Programme for Clinicians Fellow at the University of Cambridge. S.J. Marciniak is a Medical Research Council Senior
Clinical Fellow. J. Wason is funded by the Cambridge Biomedical Research Centre. Funding information for this article
has been deposited with FundRef.This is the final version of the article. It first appeared from the European Respiratory Society via http://dx.doi.org/10.1183/09031936.0011861
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