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A modified in situ RT-PCR method for localizing fungal-specific gene expression in Candida-infected mice renal cells

Yong VC, Ong KW, Sidik SM, Rosli R, Chong PP

J Microbiol Methods, 2009 Nov;79(2):242-5.
PMID: 19737582 DOI: 10.1016/j.mimet.2009.08.019

In situ Reverse Transcriptase PCR (in situ RT-PCR) can amplify mRNA and localize gene expression in cells. However, this method is not feasible in fungi as the thick fungal cell wall constitutes a barrier to this procedure. We developed a two step in situ RT-PCR procedure which enabled the detection and localization of Candida tropicalis mRNA expression in formalin-fixed, paraffin-embedded (FFPE) mouse kidney sections. This in situ hybridization study revealed the first direct evidence for deposition of Candida tropicalis secreted aspartic proteinase 2 (CtSAP2) in the tip of pseudohyphae and its involvement in acute systemic candidiasis. We conclude that in situ RT-PCR can be successfully applied to FFPE tissues and will offer new perspectives in studying gene expression in Candida species.
Molecular identification of Candida orthopsilosis isolated from blood culture

Yong PV, Chong PP, Lau LY, Yeoh RS, Jamal F

Mycopathologia, 2008 Feb;165(2):81-7.
PMID: 18266075 DOI: 10.1007/s11046-007-9086-8

The incidence of candidemia and invasive candidiasis have increased markedly due to the increasing number of immunocompromised patients. There are five major medically important species of Candida with their frequency of isolation in the diminishing order namely Candida albicans, Candida parapsilosis, Candida tropicalis, Candida glabrata and Candida krusei. In addition, there are numerous other species of Candida which differ in their genetic makeup, virulence properties, drug susceptibilities and sugar assimilation capabilities. In this report, an unusual Candida species was isolated from the blood of two leukaemic patients. Conventional culture and biochemical tests identified the Candida species as C. parapsilosis. Using fungal-specific oligonucleotide primers ITS1 and ITS4, we managed to amplify the ribosomal RNA gene and its internal transcribed spacer region from the genomic DNA of these isolates. The PCR products were then purified and subjected to automated DNA sequencing using BLAST and CLUSTAL sequence analysis identified these isolates to be Candida orthopsilosis. Candida orthopsilosis is a new species recently identified in 2005, being morphologically indistinguishable from C. parapsilosis and was previously classified as a subspecies of C. parapsilosis. This report highlights the importance of complementing traditional culture and biochemical-based identification methods with DNA-based molecular assays such as PCR as the latter is more superior in terms of its discriminatory power and speed.
Distribution and haplotype associations of XPD Lys751Gln, XRCC1 Arg280His and XRCC1 Arg399Gln polymorphisms with nasopharyngeal carcinoma in the Malaysian population

Visuvanathan S, Chong PP, Yap YY, Lim CC, Tan MK, Lye MS

Asian Pac J Cancer Prev, 2014;15(6):2747-51.
PMID: 24761895

BACKGROUND: DNA repair pathways play a crucial role in maintaining the human genome. Previous studies associated DNA repair gene polymorphisms (XPD Lys751Gln, XRCC1 Arg280His and XRCC1 Arg399Gln) with nasopharyngeal carcinoma. These non-synonymous polymorphisms may alter DNA repair capacity and thus increase or decrease susceptibility. The present study aimed to determine the genotype distribution of XPD codon 751, XRCC1 codon 280 and codon 399 polymorphisms and haplotype associations among NPC cases and controls in the Malaysian population.
MATERIALS AND METHODS: We selected 157 NPC cases and 136 controls from two hospitals in Kuala Lumpur, Malaysia for this study. The polymorphisms studied were genotyped by PCR-RFLP assay and allele and genotype frequencies, haplotype and linkage disequilibrium were determined using SNPstat software.
RESULTS: For the XPD Lys751Gln polymorphism, the frequency of the Lys allele was higher in cases than in controls (94.5% versus 85.0%). For the XRCC1 Arg280His polymorphism, the frequency of Arg allele was 90.0% and 89.0% in cases and controls, respectively and for XRCC1 Arg399Gln the frequency of the Arg allele was 72.0% and 72.8% in cases and controls respectively. All three polymorphisms were in linkage disequilibrium. The odds ratio from haplotype analysis for these three polymorphisms and their association with NPC was 1.93 (95%CI: 0.90-4.16) for haplotype CGC vs AGC allele combinations. The global haplotype association with NPC gave a p-value of 0.054.
CONCLUSIONS: Our study provides an estimate of allele and genotype frequencies of XRCC1Arg280His, XRCC1 Arg399Gln and XPD Lys751Gln polymorphisms in the Malaysian population and showed no association with nasopharyngeal cancer.
Detection of 10 medically important Candida species by seminested polymerase chain reaction

Than LT, Chong PP, Ng KP, Seow HF

Diagn Microbiol Infect Dis, 2012 Feb;72(2):196-8.
PMID: 22154674 DOI: 10.1016/j.diagmicrobio.2011.10.008

A seminested PCR detecting ten medically important Candida species were achieved. Analytical sensitivity and specificity were not compromised.
Fulltext Detection of medically important Candida species by absolute quantitation real-time polymerase chain reaction

Than LT, Chong PP, Ng KP, Seow HF

Jundishapur J Microbiol, 2015 Jan;8(1):e14940.
PMID: 25789129 DOI: 10.5812/jjm.14940

The number of invasive candidiasis cases has risen especially with an increase in the number of immunosuppressed and immunocom promised patients. The early detection of Candida species which is specific and sensitive is important in determining the correct administration of antifungal drugs to patients.
Small interfering RNA silencing of interleukin-6 in mesenchymal stromal cells inhibits multiple myeloma cell growth

Teoh HK, Chong PP, Abdullah M, Sekawi Z, Tan GC, Leong CF, et al.

Leuk. Res., 2016 Jan;40:44-53.
PMID: 26626206 DOI: 10.1016/j.leukres.2015.10.004

Studies demonstrated that mesenchymal stromal cells (MSC) from bone marrow stroma produced high concentration of interleukin-6 (IL-6) that promoted multiple myeloma cell growth. In view of the failure of IL-6 monoclonal antibody therapy to demonstrate substantial clinical responses in early clinical trials, more effective methods are needed in order to disrupt the favourable microenvironment provided by the bone marrow stroma. In this study, we evaluated the short interfering RNA (siRNA)-mediated silencing of IL-6 in MSC and the efficacy of these genetically modified MSC, with IL-6 suppression, on inhibition of U266 multiple myeloma cell growth. IL-6 mRNA and protein were significantly suppressed by 72h post IL-6 siRNA transfection without affecting the biological properties of MSC. Here we show significant inhibition of cell growth and IL-6 production in U266 cells co-cultured with MSC transfected with IL-6 siRNA when compared to U266 cells co-cultured with control MSC. We also show that the tumour volume and mitotic index of tumours in nude mice co-injected with U266 and MSC transfected with IL-6 siRNA were significantly reduced compared to tumours of mice co-injected with control MSC. Our results suggest potential use of RNA interference mediated therapy for multiple myeloma.
Short hairpin RNA silencing of interleukin-6 in human bone marrow-derived mesenchymal stromal cells inhibits multiple myeloma cell growth

Teoh HK, Chong PP, Abdullah M, Sekawi Z, Tan GC, Leong CF, et al.

Pathology, 2016 Feb;48 Suppl 1:S99.
PMID: 27773219 DOI: 10.1016/j.pathol.2015.12.283
Treatment outcomes of alginate-embedded allogenic mesenchymal stem cells versus autologous chondrocytes for the repair of focal articular cartilage defects in a rabbit model

Tay LX, Ahmad RE, Dashtdar H, Tay KW, Masjuddin T, Ab-Rahim S, et al.

Am J Sports Med, 2012 Jan;40(1):83-90.
PMID: 21917609 DOI: 10.1177/0363546511420819

Mesenchymal stem cells (MSCs) represent a promising alternative form of cell-based therapy for cartilage injury. However, the capacity of MSCs for chondrogenesis has not been fully explored. In particular, there is presently a lack of studies comparing the effectiveness of MSCs to conventional autologous chondrocyte (autoC) treatment for regeneration of full-thickness cartilage defects in vivo.
CYP1A1 MspI Polymorphism and Cervical Carcinoma Risk in the Multi-Ethnic Population of Malaysia: a Case-Control Study

Tan YH, Sidik SM, Syed Husain SN, Lye MS, Chong PP

Asian Pac J Cancer Prev, 2016;17(1):57-64.
PMID: 26838255

BACKGROUND: Tobacco smoking is considered a risk factor for cervical cancer development due to the presence of tobacco based carcinogenic metabolites in cervical cells of female smokers. In this study, we investigated the role of the T3801C (MspI) polymorphism of CYP1A1, a gene encoding an enzyme necessary for the initiation of tobacco based carcinogen metabolism, on cervical cancer risk. The T to C substitution may alter CYP1A1 activities, potentially elevating cervical cancer risk. Since results of gene-disease association studies vary according to the study population, the multi-ethnic population of Malaysia provides an excellent representative cohort for identifying and comparing the cervical cancer risk among the 3 major ethnics in Southeast Asia in relation to CYP1A1 MspI polymorphism.
MATERIALS AND METHODS: A total of 195 Thin Prep Pap smear samples from HPV negative and cancer free females were randomly selected as controls while 106 formalin fixed paraffin embedded samples from females with invasive cervical cancer were randomly selected for the cases group. The polymorphisms were identified using restriction fragment length polymorphism (RFLP) PCR.
RESULTS: We found no significant associations between CYP1A1 MspI polymorphism and cervical cancer in the general Malaysian female population. However, upon ethnic stratification, the variant C/C genotype was significantly associated with a 4.66-fold increase in cervical cancer risk in Malay females (95% CI= 1.21-17.9; p=0.03). No significant association was observed in the Chinese and Indian females. Additionally, there were no significant associations in the dominant model and allele frequency model analysis in both the general and ethnically stratified female population of Malaysia.
CONCLUSIONS: Our findings suggest that the C/C genotype of CYP1A1 MspI polymorphism is associated with the development of cervical carcinoma in the Malay females of Malaysia.
Soy husk extract improves physical and biochemical parameters of obese-diabetic rats through the regulation of PPARγ expression

Tan ST, Ismail A, Hamid M, Chong PP, Sun J

J Food Biochem, 2019 05;43(5):e12843.
PMID: 31353513 DOI: 10.1111/jfbc.12843

Unhealthy eating habits and lack of physical activities are among the contributing factors for obesity and diabetes. It has been reported that consumption of naturally occurring phenolics could exert beneficial effects toward these diseases. Therefore, this study aims to evaluate the ability of phenolic-rich soy husk powder extract (SHPE) in modifying the physical and biochemical parameters for obesity and diabetes. Forty-nine Sprague Dawley rats were divided into seven groups, including three supplementary/treatment groups. Rats in supplementary/treatment groups were provided with either 4 mg/kg BW Rosiglitazone Maleate, 250 mg SHPE/kg BW, or 500 mg SHPE/kg BW. The effectiveness of SHPE in alleviating obesity-diabetes was evaluated by measuring body weight (physical parameter), blood glucose metabolisms (biochemical parameters), and PPARγ expression. Findings in the present study revealed that short-term SHPE and Rosiglitazone Maleate administration improved the physical and biochemical parameters of obese-diabetic rats. In addition, SHPE was also demonstrated to upregulate PPARγ expression in adipocytes. These findings suggest that soy husk could emerge as a potential hypoglycemic and anti-adipogenic nutraceutical in future. PRACTICAL APPLICATIONS: This was the first study to evaluate the potential effects of soy husk against the parameters of obese-diabetes in rats. In addition, promising effects derived from this study might explore the possibility of soy husk to be utilized as an antidiabetes nutraceutical.
Fulltext Comparison of nested and ELISA based polymerase chain reaction assays for detecting Chlamydia trachomatis in pregnant women with preterm complications

Sulaiman S, Chong PP, Mokhtarudin R, Lye MS, Wan Hassan WH

Trop Biomed, 2014 Mar;31(1):36-45.
PMID: 24862043 MyJurnal

Identification of pregnant women infected with Chlamydia trachomatis is essential to allow early antibiotic treatment in order to prevent adverse pregnancy outcomes. In this study, two nucleic acid amplification tests (NAAT) namely nested PCR (BioSewoom, Korea) and Amplicor CT/NG (Roche Diagnostic, USA) were evaluated in terms of sensitivity and specificity for the detection of C. trachomatis DNA in pregnant women with preterm complications. A cross-sectional study was carried out in two public hospitals in Southern Selangor, Malaysia. Endocervical swabs obtained were subjected to DNA amplification using nested PCR (BioSewoom, Korea) and Amplicor CT/NG (Roche Diagnostic, USA). A total of 83 endocervical swabs obtained from pregnant women of less than 37 weeks gestation and presented with preterm complications were subjected to chlamydial DNA detection using both assays. The study shows that Amplicor CT/NG assay is more effective in the detection of C. trachomatis DNA from endocervical swabs compared to Biosewoom nested PCR kit. Agreement between the two assays were poor (kappa=0.094) with nested PCR showing a low sensitivity of 10.81% and a 97.83% specificity when compared to Amplicor CT/NG. The results obtained indicated that BioSewoom nested PCR was less sensitive than Amplicor CT/ NG for detecting C. trachomatis in endocervical specimens and that another more reliable test is required for confirmatory result.
Clinical accuracy and agreement between tympanic and forehead body temperature measurements for screening of patients with COVID-19

Sharif Nia H, Chong PP, Yiong Huak C, Gorgulu O, Taghipour B, Sivarajan Froelicher E, et al.

J Clin Nurs, 2021 Dec 15.
PMID: 34908206 DOI: 10.1111/jocn.16166

AIM: To investigate the accuracy, reliability and agreement between infrared forehead thermometers versus infrared tympanic thermometers temperature, a cross-sectional study was conducted in April 2020.
METHODS: The forehead and tympanic temperatures of 615 subjects were measured simultaneously in three exposed SARS-COV-2 groups at one hospital in Iran, during April 2020. These comparisons were evaluated by Bland-Altman Plot, repeatability, Passing-Bablok regression and Lin's concordance correlation coefficient. The receiver operating characteristic (ROC) analysis was done to describe the discrimination accuracy of a diagnostic test. The study adhered to STROBE checklist for cross-sectional studies.
RESULTS: A Bland-Altman plot indicated that the limits of agreement between the forehead and tympanic temperature were -0.259 to +0.19°C. Passing-Bablok regression analysis illustrated that the infrared forehead was not linearly related to tympanic temperatures (reference method), with a slope estimate that was significantly different from 1.00. The infrared forehead thermometer showed poor precision and lower accuracy than the tympanic. The forehead temperature readings had 60.0% sensitivity and 44.4% specificity (p > .05) to predict disease.
CONCLUSION: According to the results of study, there is no evidence that the assessment of temperature by infrared forehead thermometer could discriminate between the two groups (positive and negative).
Fulltext Emergence and molecular mechanisms of SARS-CoV-2 and HIV to target host cells and potential therapeutics

Saleemi MA, Ahmad B, Benchoula K, Vohra MS, Mea HJ, Chong PP, et al.

Infect Genet Evol, 2020 11;85:104583.
PMID: 33035643 DOI: 10.1016/j.meegid.2020.104583

The emergence of a new coronavirus, in around late December 2019 which had first been reported in Wuhan, China has now developed into a massive threat to global public health. The World Health Organization (WHO) has named the disease caused by the virus as COVID-19 and the virus which is the culprit was renamed from the initial novel respiratory 2019 coronavirus to SARS-CoV-2. The person-to-person transmission of this virus is ongoing despite drastic public health mitigation measures such as social distancing and movement restrictions implemented in most countries. Understanding the source of such an infectious pathogen is crucial to develop a means of avoiding transmission and further to develop therapeutic drugs and vaccines. To identify the etiological source of a novel human pathogen is a dynamic process that needs comprehensive and extensive scientific validations, such as observed in the Middle East respiratory syndrome (MERS), severe acute respiratory syndrome (SARS), and human immunodeficiency virus (HIV) cases. In this context, this review is devoted to understanding the taxonomic characteristics of SARS-CoV-2 and HIV. Herein, we discuss the emergence and molecular mechanisms of both viral infections. Nevertheless, no vaccine or therapeutic drug is yet to be approved for the treatment of SARS-CoV-2, although it is highly likely that new effective medications that target the virus specifically will take years to establish. Therefore, this review reflects the latest repurpose of existing antiviral therapeutic drug choices available to combat SARS-CoV-2.
Fulltext Approaches for Mitigating Microbial Biofilm-Related Drug Resistance: A Focus on Micro- and Nanotechnologies

Rao H, Choo S, Rajeswari Mahalingam SR, Adisuri DS, Madhavan P, Md Akim A, et al.

Molecules, 2021 Mar 26;26(7).
PMID: 33810292 DOI: 10.3390/molecules26071870

Biofilms play an essential role in chronic and healthcare-associated infections and are more resistant to antimicrobials compared to their planktonic counterparts due to their (1) physiological state, (2) cell density, (3) quorum sensing abilities, (4) presence of extracellular matrix, (5) upregulation of drug efflux pumps, (6) point mutation and overexpression of resistance genes, and (7) presence of persister cells. The genes involved and their implications in antimicrobial resistance are well defined for bacterial biofilms but are understudied in fungal biofilms. Potential therapeutics for biofilm mitigation that have been reported include (1) antimicrobial photodynamic therapy, (2) antimicrobial lock therapy, (3) antimicrobial peptides, (4) electrical methods, and (5) antimicrobial coatings. These approaches exhibit promising characteristics for addressing the impending crisis of antimicrobial resistance (AMR). Recently, advances in the micro- and nanotechnology field have propelled the development of novel biomaterials and approaches to combat biofilms either independently, in combination or as antimicrobial delivery systems. In this review, we will summarize the general principles of clinically important microbial biofilm formation with a focus on fungal biofilms. We will delve into the details of some novel micro- and nanotechnology approaches that have been developed to combat biofilms and the possibility of utilizing them in a clinical setting.
Antifungal susceptibilities, biofilms, phospholipase and proteinase activities in the Candida rugosa complex and Candida pararugosa isolated from tertiary teaching hospitals

Peremalo T, Madhavan P, Hamzah S, Than L, Wong EH, Nasir MDM, et al.

J Med Microbiol, 2019 Mar;68(3):346-354.
PMID: 30724730 DOI: 10.1099/jmm.0.000940

PURPOSE: Non-albicansCandida species have emerged as fungal pathogens that cause invasive infections, with many of these species displaying resistance to commonly used antifungal agents. This study was confined to studying the characteristics of clinical isolates of the C. rugosa complex and C. pararugosa species.
METHODOLOGY: Seven isolates of the C. rugosa complex and one isolate of C. pararugosa were obtained from two tertiary referral hospitals in Malaysia. Their antifungal susceptibilities, biofilm, proteinase, phospholipase, esterase and haemolysin activities were characterized. Biofilms were quantified using crystal violet (CV) and tetrazolium (XTT) reduction assays at 1.5, 6, 18, 24, 48 and 72 h.Results/Key findings. The E-test antifungal tests showed that both species have elevated MICs compared to C. albicans and C. tropicalis. The highest biomass was observed in one of the C. rugosa isolates (0.237), followed by C. pararugosa (0.206) at 18 h of incubation. However, the highest bioactivity was observed in the C. rugosa ATCC 10571 strain at 24 h (0.075), followed by C. pararugosa at 48 h (0.048) and the same C. rugosa strain at 24 h (0.046), with P<0.05. All isolates exhibited high proteinase activity (+++) whereas six isolates showed very strong esterase activity (++++). All the isolates were alpha haemolytic producers. None of the isolates exhibited phospholipase activity.
CONCLUSION: Elevated MICs were shown for the C. rugosa complex and C. pararugosa for commonly used antifungal drugs. Further studies to identify virulence genes involved in the pathogenesis and genes that confer reduced drug susceptibility in these species are proposed.
Growth, biofilm formation, antifungal susceptibility and oxidative stress resistance of Candida glabrata are affected by different glucose concentrations

Ng TS, Desa MNM, Sandai D, Chong PP, Than LTL

Infect Genet Evol, 2016 06;40:331-338.
PMID: 26358577 DOI: 10.1016/j.meegid.2015.09.004

Glucose is an important fuel source to support many living organisms. Its importance in the physiological fitness and pathogenicity of Candida glabrata, an emerging human fungal pathogen has not been extensively studied. The present study aimed to investigate the effects of glucose on the growth, biofilm formation, antifungal susceptibility and oxidative stress resistance of C. glabrata. In addition, its effect on the expression of a putative high affinity glucose sensor gene, SNF3 was also investigated. Glucose concentrations were found to exert effects on the physiological responses of C. glabrata. The growth rate of the species correlated positively to the amount of glucose. In addition, low glucose environments were found to induce C. glabrata to form biofilm and resist amphotericin B. Conversely, high glucose environments promoted oxidative stress resistance of C. glabrata. The expression of CgSNF3 was found to be significantly up-regulated in low glucose environments. The expression of SNF3 gene in clinical isolates was found to be higher compared to ATCC laboratory strains in low glucose concentrations, which may explain the better survivability of clinical isolates in the low glucose environment. These observations demonstrated the impact of glucose in directing the physiology and virulence fitness of C. glabrata through the possible modulation by SNF3 as a glucose sensor, which in turn aids the species to adapt, survive and thrive in hostile host environment.
Fulltext Phylogenetic and Transcripts Profiling of Glucose Sensing Related Genes in Candida glabrata

Ng TS, Mohd Desa MN, Sandai D, Chong PP, Than LT

Jundishapur J Microbiol, 2015 Nov;8(11):e25177.
PMID: 26855740 DOI: 10.5812/jjm.25177

BACKGROUND: The sensing mechanism of glucose in Saccharomyces cerevisiae is well studied. However, such information is scarcely found in other yeast species such as Candida glabrata.
OBJECTIVES: This study aimed to identify the glucose sensing pathway related genes of C. glabrata and to analyze the regulation pattern of these genes in response to different surrounding glucose concentrations through the quantitative real time polymerase chain reaction (qRT-PCR).
MATERIALS AND METHODS: Phylogenetic analysis was carried out on predicted amino acid sequences of C. glabrata and S. cerevisiae to compare their degree of similarity. In addition, the growth of C. glabrata in response to different amounts of glucose (0%, 0.01%, 0.1%, 1% and 2%) was evaluated via the spot dilution assay on prepared agar medium. Besides, the SNF3 and RGT2, which act as putative glucose sensors, and the RGT1 and MIG1, which act as putative transcriptional regulators and selected downstream hexose transporters (HXTs), were analysed through qRT-PCR analysis for the gene expression level under different glucose concentrations.
RESULTS: Comparative analysis of predicted amino acids in the phylogenetic tree showed high similarity between C. glabrata and S cerevisiae. Besides, C. glabrata demonstrated the capability to grow in glucose levels as low as 0.01% in the spot dilution assay. In qRT-PCR analysis, differential expressions were observed in selected genes when C. glabrata was subjected to different glucose concentrations.
CONCLUSIONS: The constructed phylogenetic tree suggests the close evolutionary relationship between C. glabrata and S. cerevisiae. The capability of C. glabrata to grow in extremely low glucose environments and the differential expression of selected glucose-sensing related genes suggested the possible role of these genes in modulating the growth of C. glabrata in response to different glucose concentrations. This study helps deepen our understanding of the glucose sensing mechanism in C. glabrata and serves to provide fundamental data that may assist in unveiling this mechanism as a potential drug target.
Fulltext SNF3 as High Affinity Glucose Sensor and Its Function in Supporting the Viability of Candida glabrata under Glucose-Limited Environment

Ng TS, Chew SY, Rangasamy P, Mohd Desa MN, Sandai D, Chong PP, et al.

Front Microbiol, 2015;6:1334.
PMID: 26648919 DOI: 10.3389/fmicb.2015.01334

Candida glabrata is an emerging human fungal pathogen that has efficacious nutrient sensing and responsiveness ability. It can be seen through its ability to thrive in diverse range of nutrient limited-human anatomical sites. Therefore, nutrient sensing particularly glucose sensing is thought to be crucial in contributing to the development and fitness of the pathogen. This study aimed to elucidate the role of SNF3 (Sucrose Non Fermenting 3) as a glucose sensor and its possible role in contributing to the fitness and survivability of C. glabrata in glucose-limited environment. The SNF3 knockout strain was constructed and subjected to different glucose concentrations to evaluate its growth, biofilm formation, amphotericin B susceptibility, ex vivo survivability and effects on the transcriptional profiling of the sugar receptor repressor (SRR) pathway-related genes. The CgSNF3Δ strain showed a retarded growth in low glucose environments (0.01 and 0.1%) in both fermentation and respiration-preferred conditions but grew well in high glucose concentration environments (1 and 2%). It was also found to be more susceptible to amphotericin B in low glucose environment (0.1%) and macrophage engulfment but showed no difference in the biofilm formation capability. The deletion of SNF3 also resulted in the down-regulation of about half of hexose transporters genes (four out of nine). Overall, the deletion of SNF3 causes significant reduction in the ability of C. glabrata to sense limited surrounding glucose and consequently disrupts its competency to transport and perform the uptake of this critical nutrient. This study highlighted the role of SNF3 as a high affinity glucose sensor and its role in aiding the survivability of C. glabrata particularly in glucose limited environment.
The mycological and molecular study of Hortaea werneckii isolated from blood and splenic abscess

Ng KP, Soo-Hoo TS, Na SL, Tay ST, Hamimah H, Lim PC, et al.

Mycopathologia, 2005 Jun;159(4):495-500.
PMID: 15983734

Hortaea werneckii is an environmental dematiaceous fungus found in the halophilic environment. It causes tinea nigra. We report the isolation of H. werneckii from blood and splenic abscess of two patients with acute myelomonocytic leukaemia. H. werneckii grew at room temperature but not at 37 degrees C, it was identified by biochemical tests, growth characteristics and the presence of conspicuous collarette intercalary on dividing yeast cells. The use of specific oligonucleotide primer Hor-F (5'-TGGACACCTTCA TAACTCTTG-3') and Hor-R (5'-TCACAACGCTTAGAGACGG-3') confirmed the two isolates were H. werneckii. The sequence for 281 nucleotide of HW299 and HW403 were 99% identical but differed only in one nucleotide. In vitro anti-fungal susceptibility testing showed that the isolates were resistant to amphotericin B and flucytosine.
Fulltext Lung-infiltrating T helper 17 cells as the major source of interleukin-17A production during pulmonary Cryptococcus neoformans infection

Movahed E, Cheok YY, Tan GMY, Lee CYQ, Cheong HC, Velayuthan RD, et al.

BMC Immunol, 2018 Nov 08;19(1):32.
PMID: 30409128 DOI: 10.1186/s12865-018-0269-5

BACKGROUND: IL-17A has emerged as a key player in the pathologies of inflammation, autoimmune disease, and immunity to microbes since its discovery two decades ago. In this study, we aim to elucidate the activity of IL-17A in the protection against Cryptococcus neoformans, an opportunistic fungus that causes fatal meningoencephalitis among AIDS patients. For this purpose, we examined if C. neoformans infection triggers IL-17A secretion in vivo using wildtype C57BL/6 mice. In addition, an enhanced green fluorescence protein (EGFP) reporter and a knockout (KO) mouse models were used to track the source of IL-17A secretion and explore the protective function of IL-17A, respectively.
RESULTS: Our findings showed that in vivo model of C. neoformans infection demonstrated induction of abundant IL-17A secretion. By examining the lung bronchoalveolar lavage fluid (BALF), mediastinal lymph node (mLN) and spleen of the IL-17A-EGFP reporter mice, we showed that intranasal inoculation with C. neoformans promoted leukocytes lung infiltration. A large proportion (~ 50%) of the infiltrated CD4+ helper T cell population secreted EGFP, indicating vigorous TH17 activity in the C. neoformans-infected lung. The infection study in IL-17A-KO mice, on the other hand, revealed that absence of IL-17A marginally boosted fungal burden in the lung and accelerated the mouse death.
CONCLUSION: Therefore, our data suggest that IL-17A is released predominantly from TH17 cells in vivo, which plays a supporting role in the protective immunity against C. neoformans infection.

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