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1.  Biocontrol potential of three novel Trichoderma strains: isolation, evaluation and formulation 
3 Biotech  2013;4(3):275-281.
We have isolated three novel strains of Trichoderma (two T. harzianum and one T. atroviride) from wild mushroom and tree bark, and evaluated their biocontrol potential against Sclerotium delphinii infecting cultivated cotton seedlings. T. harzianum strain CICR-G, isolated as a natural mycoparasite on a tree-pathogenic Ganoderma sp. exhibited the highest disease suppression ability. This isolate was formulated into a talcum-based product and evaluated against the pathogen in non-sterile soil. This isolate conidiated profusely under conditions that are non-conducive for conidiation by three other Trichoderma species tested, thus having an added advantage from commercial perspective.
doi:10.1007/s13205-013-0150-4
PMCID: PMC4026447
Trichoderma;  Biological control;  Formulation; Sclerotium delphinii;  Cotton
2.  Identification of gentian violet concentration that does not stain oral mucosa, possesses anti-candidal activity and is well tolerated 
Gentian violet (GV) is recommended for initial treatment of oral candidiasis in HIV-infected patients in resource-limited settings. Currently GV is not used because of its staining effects. In this study, we investigated the staining capacity of three different concentrations of GV to determine a concentration that does not cause staining. The selected concentration that did not cause staining was evaluated for its physical stability and antifungal activity. Fifteen healthy participants were randomized to rinse twice daily for 14 days with one of three GV concentrations: 0.1%, 0.0085%, or 0.00165%. Oral examination and intra-oral photographs were performed at baseline and at the end of therapy. Participants responded to a questionnaire to assess adverse events. Antifungal activity was evaluated using the Clinical and Laboratory Standard Institute methodology. GV at a concentration of 0.00165% did not stain the oral mucosa and was well tolerated. GV at a concentration of 0.00165% was stable and possessed antifungal activity when stored at certain temperatures for different time periods. Gentian violet solution at the concentration of 0.00165% does not stain the oral mucosa, is stable and possesses potent antifungal activity.
doi:10.1007/s10096-010-1131-8
PMCID: PMC3076549  PMID: 21210170
3.  Agar-Based Disk Diffusion Assay for Susceptibility Testing of Dermatophytes ▿  
Journal of Clinical Microbiology  2010;48(10):3750-3752.
Currently, no agar-based susceptibility testing method has been standardized for testing dermatophytes. We describe a newly developed agar-based method employing disk diffusion assay to test the susceptibility of 47 isolates of dermatophytes against 8 antifungals. Our results show that the method is reproducible, is simple, and could be used to determine the antifungal susceptibility of dermatophytes.
doi:10.1128/JCM.01357-10
PMCID: PMC2953072  PMID: 20668120
4.  Docosanoids are multifunctional regulators of neural cell integrity and fate: significance in aging and disease 
The identification of neuroprotectin D1 (NPD1), a biosynthetic product of docosahexaenoic acid (DHA), in brain and retina as well as the characterization of its bioactivity, is generating a renewed interest in the functional role and pathophysiological significance of omega-3 fatty acids in the central nervous system.
Neurotrophins, particularly pigment epithelium-derived factor (PEDF), induce NPD1 synthesis and its polarized apical secretion, implying paracrine and autocrine bioactivity of this lipid mediator. Also, DHA and PEDF synergistically activate NPD1 synthesis and antiapoptotic protein expression and decreased proapoptotic Bcl-2 protein expression and caspase 3 activation during oxidative stress.
In experimental stroke, endogenous NPD1 synthesis was found to be upregulated, and the infusion of the lipid mediator into the brain under these conditions revealed neuroprotective bioactivity of NPD1.
The hippocampal CA1 region from Alzheimer’s disease (AD) patients (rapidly sampled) shows a major reduction in NPD1.
The interplay of DHA-derived neuroprotective signaling aims to counteract proinflammatory, cell-damaging events triggered by multiple, converging cytokine and amyloid peptide factors, as in the case of AD. Generation of NPD1 from DHA thereby appears to redirect cellular fate toward successful preservation of retinal pigment epithelial (RPE)-photoreceptor cell integrity and brain cell aging. The Bcl-2 pro- and antiapoptotic proteins, neurotrophins, and NPD1, lie along a cell fate-regulatory pathway whose component members are highly interactive, and have potential to function cooperatively in cell survival. Agents that stimulate NPD1 biosynthesis, NPD1 analogs, or dietary regimens may be useful as new preventive/therapeutic strategies for neurodegenerative diseases.
doi:10.1016/j.plefa.2007.10.022
PMCID: PMC2696125  PMID: 18060755
5.  Uses and Limitations of the XTT Assay in Studies of Candida Growth and Metabolism 
Journal of Clinical Microbiology  2003;41(1):506-508.
Colorimetric tetrazolium assays are used increasingly in studies of fungi, often in the absence of standardization or correlation with other methods. We examined species- and strain-related tetrazolium metabolism in Candida albicans and Candida parapsilosis by using XTT {2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino) carbonyl]-2H-tetrazolium hydroxide} and WST-8 [2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulphonyl)-2H-tetrazolium] and found marked variations. Also, significant signal was often missed in the absence of dimethyl sulfoxide extraction.
doi:10.1128/JCM.41.1.506-508.2003
PMCID: PMC149594  PMID: 12517908
6.  Antifungal Susceptibility of Candida Biofilms: Unique Efficacy of Amphotericin B Lipid Formulations and Echinocandins 
Biofilms, likely the predominant mode of device-related microbial infection, exhibit resistance to antimicrobial agents. Evidence suggests that Candida biofilms have dramatically reduced susceptibility to antifungal drugs. We examined antifungal susceptibilities of Candida albicans and Candida parapsilosis biofilms grown on a bioprosthetic model. In addition to conventional agents, we determined if new antifungal agents (triazoles, amphotericin B lipid formulations, and echinocandins) have activities against Candida biofilms. We also explored effects of preincubation of C. albicans cells with subinhibitory concentrations (sub-MICs) of drugs to see if they could modify subsequent biofilm formation. Finally, we used confocal scanning laser microscopy (CSLM) to image planktonic- and biofilm-exposed blastospores to examine drug effects on cell structure. Candida biofilms were formed on silicone elastomer and quantified by tetrazolium and dry weight (DW) assays. Susceptibility testing of fluconazole, nystatin, chlorhexidine, terbenafine, amphotericin B (AMB), and the triazoles voriconazole (VRC) and ravuconazole revealed resistance in all Candida isolates examined when grown as biofilms, compared to planktonic forms. In contrast, lipid formulations of AMB (liposomal AMB and AMB lipid complex [ABLC]) and echinocandins (caspofungin [Casp] and micafungin) showed activity against Candida biofilms. Preincubation of C. albicans cells with sub-MIC levels of antifungals decreased the ability of cells to subsequently form biofilm (measured by DW; P < 0.0005). CSLM analysis of planktonic and biofilm-associated blastospores showed treatment with VRC, Casp, and ABLC resulted in morphological alterations, which differed with each agent. In conclusion, our data show that Candida biofilms show unique susceptibilities to echinocandins and AMB lipid formulations.
doi:10.1128/AAC.46.6.1773-1780.2002
PMCID: PMC127206  PMID: 12019089
7.  Comparison of Biofilms Formed by Candida albicans and Candida parapsilosis on Bioprosthetic Surfaces 
Infection and Immunity  2002;70(2):878-888.
Little is known about fungal biofilms, which may cause infection and antibiotic resistance. In this study, biofilm formation by different Candida species, particularly Candida albicans and C. parapsilosis, was evaluated by using a clinically relevant model of Candida biofilm on medical devices. Candida biofilms were allowed to form on silicone elastomer and were quantified by tetrazolium (XTT) and dry weight (DW) assays. Formed biofilm was visualized by using fluorescence microscopy and confocal scanning laser microscopy with Calcofluor White (Sigma Chemical Co., St. Louis, Mo.), concanavalin A-Alexafluor 488 (Molecular Probes, Eugene, Oreg.), and FUN-1 (Molecular Probes) dyes. Although minimal variations in biofilm production among invasive C. albicans isolates were seen, significant differences between invasive and noninvasive isolates (P < 0.001) were noted. C. albicans isolates produced more biofilm than C. parapsilosis, C. glabrata, and C. tropicalis isolates, as determined by DW assays (P was <0.001 for all comparisons) and microscopy. Interestingly, noninvasive isolates demonstrated a higher level of XTT activity than invasive isolates. On microscopy, C. albicans biofilms had a morphology different from that of other species, consisting of a basal blastospore layer with a dense overlying matrix composed of exopolysaccharides and hyphae. In contrast, C. parapsilosis biofilms had less volume than C. albicans biofilms and were comprised exclusively of clumped blastospores. Unlike planktonically grown cells, Candida biofilms rapidly (within 6 h) developed fluconazole resistance (MIC, >128 μg/ml). Importantly, XTT and FUN-1 activity showed biofilm cells to be metabolically active. In conclusion, our data show that C. albicans produces quantitatively larger and qualitatively more complex biofilms than other species, in particular, C. parapsilosis.
PMCID: PMC127692  PMID: 11796623
8.  James Keane 
BMJ : British Medical Journal  2002;324(7330):174.
PMCID: PMC1122091

Results 1-8 (8)