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Lu Y, Ogawa M, García JM, Nitin N. Filamentous fungal pellets as a novel and sustainable encapsulation matrix for exogenous bioactive compounds. Food Funct 2024; 15:3087-3097. [PMID: 38415776 DOI: 10.1039/d3fo04425d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
Abstract
Edible filamentous fungi (FF) are considered sustainable food materials given their rich nutrient profile and low carbon and water footprints during production. The current study evaluated FF biomass as a natural encapsulation system for exogenous bioactive compounds and as a model system to investigate the complex food matrix-micronutrient interactions during in vitro digestion. Our objective was to compare the fungal pellet, as a multicellular encapsulation system, with single yeast cell-based carriers in terms of loading and release of curcumin, a model compound. The results suggest that the curcumin encapsulation efficiency was similar in single yeast cells and fungal hyphal cells. A vacuum treatment used to facilitate the infusion of curcumin into yeast or fungal cells also enabled rapid internalization of yeast cells into the fungal pellet matrix. Compared to the single-cell encapsulation system, the multicellular systems modified the release kinetics of curcumin during in vitro digestion by eliminating the initial rapid release and reducing the overall release rate of curcumin in the small intestinal phase. These results provide a deeper understanding of the effect of natural edible structures on the bioaccessibility of micronutrients, and demonstrate the potential of using FF biomass as functional food materials.
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Affiliation(s)
- Yixing Lu
- Department of Food Science and Technology, University of California-Davis, Davis, CA 95616, USA.
| | - Minami Ogawa
- Department of Food Science and Technology, University of California-Davis, Davis, CA 95616, USA.
| | - Jaime Moreno García
- Department of Agricultural Chemistry, Edaphology and Microbiology, University of Córdoba, 14014 Córdoba, Spain
| | - Nitin Nitin
- Department of Food Science and Technology, University of California-Davis, Davis, CA 95616, USA.
- Department of Biological and Agricultural Engineering, University of California-Davis, Davis, CA 95616, USA
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2
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Lichius A. Concentration, cellular exposure and specificity of organelle selective fluorescent dyes in fungal cell biology. FUNGAL BIOL REV 2021. [DOI: 10.1016/j.fbr.2021.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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3
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Morphological and physicochemical diversity of snow algae from Alaska. Sci Rep 2020; 10:19167. [PMID: 33154522 PMCID: PMC7644681 DOI: 10.1038/s41598-020-76215-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 10/23/2020] [Indexed: 11/08/2022] Open
Abstract
Snow algae are photosynthetic microbes growing in thawing snow. They usually show various morphological cell types. The aim of this study was to carry out microscopic and spectroscopic analysis of different forms of cells of snow algae collected on glaciers in Alaska. Four different shapes of algal cells were observed with the use of bright field LM (Light Microscopy), DIC (Differential Interference Contrast), EDF (Extended Depth Focus), fluorescence microscopy, and SEM (Scanning Electron Microscopy). The cells exhibited the strongest autofluorescence after the exposure to 365-nm excitation light, and the intensity differed among the cell types. Zygotes (cysts) showed the most intense fluorescence. Acridine orange staining revealed the acid nature of the algal cells. The use of Congo red and Calcofluor white fluorochromes indicated differences in the structure of polysaccharides in the cell wall in the individual types of algal cells. FTIR (Fourier-Transform Infrared Spectroscopy) analyses showed the presence of polysaccharides not only in the algal cells but also in the fixative solution. The presence of polysaccharides in the extracellular algal fraction was confirmed by X-ray dispersion spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy imaging (SEM). The differences observed in the structure of the cell wall of the different forms of red snow algae prompt further analysis of this structure.
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Rosenberg M, Visnapuu M, Vija H, Kisand V, Kasemets K, Kahru A, Ivask A. Selective antibiofilm properties and biocompatibility of nano-ZnO and nano-ZnO/Ag coated surfaces. Sci Rep 2020; 10:13478. [PMID: 32778787 PMCID: PMC7417576 DOI: 10.1038/s41598-020-70169-w] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 07/06/2020] [Indexed: 12/16/2022] Open
Abstract
Spread of pathogenic microbes and antibiotic-resistant bacteria in health-care settings and public spaces is a serious public health challenge. Materials that prevent solid surface colonization or impede touch-transfer of viable microbes could provide means to decrease pathogen transfer from high-touch surfaces in critical applications. ZnO and Ag nanoparticles have shown great potential in antimicrobial applications. Less is known about nano-enabled surfaces. Here we demonstrate that surfaces coated with nano-ZnO or nano-ZnO/Ag composites are not cytotoxic to human keratinocytes and possess species-selective medium-dependent antibiofilm activity against Escherichia coli, Staphylococcus aureus and Candida albicans. Colonization of nano-ZnO and nano-ZnO/Ag surfaces by E. coli and S. aureus was decreased in static oligotrophic conditions (no planktonic growth). Moderate to no effect was observed for bacterial biofilms in growth medium (supporting exponential growth). Inversely, nano-ZnO surfaces enhanced biofilm formation by C. albicans in oligotrophic conditions. However, enhanced C. albicans biofilm formation on nano-ZnO surfaces was effectively counteracted by the addition of Ag. Possible selective enhancement of biofilm formation by the yeast C. albicans on Zn-enabled surfaces should be taken into account in antimicrobial surface development. Our results also indicated the importance of the use of application-appropriate test conditions and exposure medium in antimicrobial surface testing.
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Affiliation(s)
- M Rosenberg
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Tallinn, Estonia.
- Department of Chemistry and Biotechnology, Tallinn University of Technology, Tallinn, Estonia.
| | - M Visnapuu
- Institute of Physics, University of Tartu, Tartu, Estonia
| | - H Vija
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Tallinn, Estonia
| | - V Kisand
- Institute of Physics, University of Tartu, Tartu, Estonia
| | - K Kasemets
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Tallinn, Estonia
| | - A Kahru
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Tallinn, Estonia
- Estonian Academy of Sciences, Tallinn, Estonia
| | - A Ivask
- Laboratory of Environmental Toxicology, National Institute of Chemical Physics and Biophysics, Tallinn, Estonia
- Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
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Kitin P, Nakaba S, Hunt CG, Lim S, Funada R. Direct fluorescence imaging of lignocellulosic and suberized cell walls in roots and stems. AOB PLANTS 2020; 12:plaa032. [PMID: 32793329 PMCID: PMC7415075 DOI: 10.1093/aobpla/plaa032] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 06/21/2020] [Indexed: 05/05/2023]
Abstract
Investigating plant structure is fundamental in botanical science and provides crucial knowledge for the theories of plant evolution, ecophysiology and for the biotechnological practices. Modern plant anatomy often targets the formation, localization and characterization of cellulosic, lignified or suberized cell walls. While classical methods developed in the 1960s are still popular, recent innovations in tissue preparation, fluorescence staining and microscopy equipment offer advantages to the traditional practices for investigation of the complex lignocellulosic walls. Our goal is to enhance the productivity and quality of microscopy work by focusing on quick and cost-effective preparation of thick sections or plant specimen surfaces and efficient use of direct fluorescent stains. We discuss popular histochemical microscopy techniques for visualization of cell walls, such as autofluorescence or staining with calcofluor, Congo red (CR), fluorol yellow (FY) and safranin, and provide detailed descriptions of our own approaches and protocols. Autofluorescence of lignin in combination with CR and FY staining can clearly differentiate between lignified, suberized and unlignified cell walls in root and stem tissues. Glycerol can serve as an effective clearing medium as well as the carrier of FY for staining of suberin and lipids allowing for observation of thick histological preparations. Three-dimensional (3D) imaging of all cell types together with chemical information by wide-field fluorescence or confocal laser scanning microscopy (CLSM) was achieved.
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Affiliation(s)
- Peter Kitin
- School of Environmental and Forest Sciences, University of Washington, Seattle, WA, USA
- Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, Fuchu-Tokyo, Japan
| | - Satoshi Nakaba
- Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, Fuchu-Tokyo, Japan
- Faculty of Agriculture, Tokyo University of Agriculture and Technology, Fuchu-Tokyo, Japan
| | | | - Sierin Lim
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, Singapore
| | - Ryo Funada
- Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, Fuchu-Tokyo, Japan
- Faculty of Agriculture, Tokyo University of Agriculture and Technology, Fuchu-Tokyo, Japan
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Signalling through the yeast MAPK Cell Wall Integrity pathway controls P-body assembly upon cell wall stress. Sci Rep 2019; 9:3186. [PMID: 30816278 PMCID: PMC6395727 DOI: 10.1038/s41598-019-40112-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 02/11/2019] [Indexed: 01/15/2023] Open
Abstract
Post-transcriptional control of mRNA is a key event in the regulation of gene expression. From yeast to human cells, P-bodies are cytoplasmic RNA-protein aggregates that play an essential role in this process, particularly under stress conditions. In this work, we show that in the model yeast Saccharomyces cerevisiae cell wall stress induces the formation of these structures. This effect is dependent on multiple elements in the Cell Wall Integrity (CWI) MAPK signalling pathway, a signal transduction cascade responsible for the maintenance of cell integrity under adverse environmental conditions. Remarkably, P-body assembly requires the catalytic activity of the MAPK of the pathway, Slt2/Mpk1. In accordance with the control exerted by this signalling pathway, the timing of P-body formation is similar to that of the activation of the CWI pathway. Noticeably, mRNAs whose expression is regulated by this pathway localize in P-bodies after the cell is exposed to stress following a temporal pattern coincident with CWI pathway activation. Moreover, when these mRNAs are overexpressed in a mutant background unable to form visible P-bodies, the cells show hypersensitivity to agents that interfere with cell wall integrity, supporting that they play a role in the mRNA lifecycle under stress conditions.
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Căpitan R, Schievano C, Noli C. Evaluation of the value of staining hair samples with a modified Wright-Giemsa stain and/or showing illustrated guidelines for the microscopic diagnosis of dermatophytosis in cats. Vet Dermatol 2018; 29:308. [PMID: 29664175 DOI: 10.1111/vde.12543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/23/2018] [Indexed: 11/29/2022]
Abstract
BACKGROUND Direct examination of the hair is a simple diagnostic test for the diagnosis of dermatophytosis; training is needed to use this test. HYPOTHESIS/OBJECTIVES To evaluate whether use of modified Wright-Giemsa blue stain and/or photographic images of infected and uninfected hairs improved the user's ability to identify infected or uninfected hairs. ANIMALS Ten cats with, and 10 cats without, dermatophytosis due to Microsporum canis (n = 20). MATERIALS AND METHODS Twenty unstained and 20 stained hair samples from each group (n = 40) were anonymized and examined by veterinarians using a light microscope. Participants recorded samples as "infected" or "uninfected". Participants were then shown and allowed to use photographic images while examining the same 40 samples. RESULTS Without staining, investigators correctly identified 12.7 ± 4 of the 20 samples (mean ± SD) and with staining 13.6 (±3). After illustrative guidelines were shown, they correctly identified a mean of 16.9 (±2.5) unstained slides and 15.8 (±2.3) stained slides. "Illustrated guidelines" and "hair infection" significantly increased the probability of a correct answer, whereas "staining" did not. Logistic regression determined that "study participant", "illustrated guidelines" (OR = 2.6) and "hair infection" (OR = 2.1) had a significant influence on the results, whereas "staining" did not. Sensitivity and specificity of direct examination were 70.5% and 56%, respectively, compared with culture status. CONCLUSIONS AND CLINICAL IMPORTANCE When examining hairs for the presence or absence of infected dermatophyte hairs, diagnostic accuracy was improved when observers used illustrated guides compared with just examining stained slides.
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Affiliation(s)
- Rareş Căpitan
- Regatul Animalelor, Sos. Panduri 31, bl P2, sector 5, RO-050655, Bucharest, Romania
| | - Carlo Schievano
- Department of Compared Biomedicine and Food Science, University of Padova, Viale dell'Università 16, 35020, Legnaro, PD, Italy
| | - Chiara Noli
- Servizi Dermatologici Veterinari, Strada Bedale della Ressia 2, 12016, Peveragno, CN, Italy
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THOMAS J, IDRIS N, COLLINGS D. Pontamine fast scarlet 4B bifluorescence and measurements of cellulose microfibril angles. J Microsc 2017; 268:13-27. [DOI: 10.1111/jmi.12582] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 04/23/2017] [Accepted: 04/26/2017] [Indexed: 02/06/2023]
Affiliation(s)
- J. THOMAS
- School of Biological Sciences; The University of Canterbury; Christchurch New Zealand
- Central Wood Testing Laboratory; The Rubber Board; Kottayam Kerala India
| | - N.A. IDRIS
- School of Biological Sciences; The University of Canterbury; Christchurch New Zealand
- School of Fundamental Sciences; Universiti Malaysia Terengganu; Kuala Nerus Kuala Terengganu Terengganu Malaysia
| | - D.A. COLLINGS
- School of Biological Sciences; The University of Canterbury; Christchurch New Zealand
- School of Environmental and Life Sciences; The University of Newcastle; Callaghan NSW Australia
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9
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Galleria mellonella lysozyme induces apoptotic changes in Candida albicans cells. Microbiol Res 2016; 193:121-131. [PMID: 27825480 DOI: 10.1016/j.micres.2016.10.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 09/30/2016] [Accepted: 10/08/2016] [Indexed: 12/22/2022]
Abstract
The greater wax moth Galleria mellonella has been increasingly used as a model host to determine Candida albicans virulence and efficacy of antifungal treatment. The G. mellonella lysozyme, similarly to its human counterpart, is a member of the c-type family of lysozymes that exhibits antibacterial and antifungal activity. However, in contrast to the relatively well explained bactericidal action, the mechanism of fungistatic and/or fungicidal activity of lysozymes is still not clear. In the present study we provide the direct evidences that the G. mellonella lysozyme binds to the protoplasts as well as to the intact C. albicans cells and decreases the survival rate of both these forms in a time-dependent manner. No enzymatic activity of the lysozyme towards typical chitinase and β-glucanase substrates was detected, indicating that hydrolysis of main fungal cell wall components is not responsible for anti-Candida activity of the lysozyme. On the other hand, pre-treatment of cells with tetraethylammonium, a potassium channel blocker, prevented them from the lysozyme action, suggesting that lysozyme acts by induction of programmed cell death. In fact, the C. albicans cells treated with the lysozyme exhibited typical apoptotic features, i.e. loss of mitochondrial membrane potential, phosphatidylserine exposure in the outer leaflet of the cell membrane, as well as chromatin condensation and DNA fragmentation.
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10
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Reappraisal of Conventional Diagnosis for Dermatophytes. Mycopathologia 2016; 182:169-180. [PMID: 27718160 DOI: 10.1007/s11046-016-0071-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 09/17/2016] [Indexed: 10/20/2022]
Abstract
Dermatophytoses include a wide variety of diseases involving glabrous skin, nails and hair. These superficial infections are a common cause of consultation in dermatology. In many cases, their diagnosis is not clinically obvious, and mycological analysis therefore is required. Direct microscopic examination of the samples using clearing agents provides a quick response to the clinician and is usually combined with cultures on specific media, which must be used to overcome the growth of contaminating moulds that may hamper the recovery of dermatophytes. Accurate identification of the causative agent (i.e. at the species level), currently based on morphological criteria, is necessary not only to initiate an appropriate treatment but also for setting prophylactic measures. However, conventional methods often lack sensitivity and species identification may require up to 4 weeks if subcultures are needed. Histological analysis, which is considered the "gold standard" for the diagnosis of onychomycoses, is seldom performed, and as direct examination, it does not allow precise identification of the pathogen. Nevertheless, a particular attention to the quality of clinical specimens is warranted. Moreover, the sensitivity of direct examination may be greatly enhanced by the use of fluorochromes such as calcofluor white. Likewise, sensitivity of the cultures could be enhanced by the use of culture media containing antifungal deactivators. With the generalization of molecular identification by gene sequencing or MALDI-TOF mass spectrometry, the contribution of historical biochemical or physiological tests to species identification of atypical isolates is now limited. Nevertheless, despite the recent availability of several PCR-based kits and an extensive literature on molecular methods allowing the detection of fungal DNA or both detection and direct identification of the main dermatophyte species, the biological diagnosis of dermatophytosis in 2016 still relies on both direct examination and cultures of appropriate clinical specimens.
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11
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Oliveira LN, Casaletti L, Báo SN, Borges CL, de Sousa Lima P, de Almeida Soares CM. Characterizing the nuclear proteome of Paracoccidioides spp. Fungal Biol 2016; 120:1209-24. [PMID: 27647238 DOI: 10.1016/j.funbio.2016.07.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 07/05/2016] [Accepted: 07/07/2016] [Indexed: 10/21/2022]
Abstract
Paracoccidioidomycosis is an endemic disease in Latin America, caused by thermo dimorphic fungi of the genus Paracoccidioides. Although previous proteome analyses of Paracoccidioides spp. have been carried out, the nuclear subproteome of this pathogen has not been described. In this way, we aimed to characterize the nuclear proteome of Paracoccidioides species, in the yeast form. For that, yeast cells were disrupted and submitted to cell fractionation. The purity of the nuclear fraction was confirmed by fluorescence and electron microscopy. Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) allowed the identification of 867 proteins. In order to support our enrichment method for nuclear proteins, bioinformatics analysis were applied that allowed the identification of 281 proteins with nuclear localization. The analysis revealed proteins related to DNA maintenance, gene expression, synthesis and processing of messenger and ribosomal RNAs, likewise proteins of nuclear-cytoplasmic traffic. It was also possible to detect some proteins that are poorly expressed, like transcription factors involved in important roles such as resistance to abiotic stress, sporulation, cellular growth and DNA and chromatin maintenance. This is the first descriptive nuclear proteome of Paracoccidioides spp. that can be useful as an important platform base for fungi-specific nuclear processes.
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Affiliation(s)
- Lucas Nojosa Oliveira
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, ICB II, Campus II, Universidade Federal de Goiás, Goiânia, Goiás, 74690-900, Brazil
| | - Luciana Casaletti
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, ICB II, Campus II, Universidade Federal de Goiás, Goiânia, Goiás, 74690-900, Brazil; Escola de Engenharia, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás, 74605-010, Brazil
| | - Sônia Nair Báo
- Laboratório de Microscopia, Departamento de Biologia Celular, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, Distrito Federal, 70910-900, Brazil
| | - Clayton Luiz Borges
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, ICB II, Campus II, Universidade Federal de Goiás, Goiânia, Goiás, 74690-900, Brazil
| | - Patrícia de Sousa Lima
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, ICB II, Campus II, Universidade Federal de Goiás, Goiânia, Goiás, 74690-900, Brazil
| | - Célia Maria de Almeida Soares
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, ICB II, Campus II, Universidade Federal de Goiás, Goiânia, Goiás, 74690-900, Brazil.
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Shamly V, Kali A, Srirangaraj S, Umadevi S. Comparison of Microscopic Morphology of Fungi Using Lactophenol Cotton Blue (LPCB), Iodine Glycerol and Congo Red Formaldehyde Staining. J Clin Diagn Res 2014; 8:DL01-2. [PMID: 25177565 DOI: 10.7860/jcdr/2014/8521.4535] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Accepted: 05/12/2014] [Indexed: 11/24/2022]
Affiliation(s)
- Vacharavel Shamly
- Postgraduate, Department of Medical Microbiology, Mahatma Gandhi Medical College & Research Institute , Pondicherry, India
| | - Arunava Kali
- Assistant Professor, Department of Microbiology, Mahatma Gandhi Medical College & Research Institute , Pondicherry, India
| | - Sreenivasan Srirangaraj
- Associate Professor, Department of Microbiology, Mahatma Gandhi Medical College & Research Institute , Pondicherry, India
| | - Sivaraman Umadevi
- Professor, Department of Microbiology, Mahatma Gandhi Medical College & Research Institute , Pondicherry, India
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13
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Deletion mutant library for investigation of functional outputs of cyclic diguanylate metabolism in Pseudomonas aeruginosa PA14. Appl Environ Microbiol 2014; 80:3384-93. [PMID: 24657857 DOI: 10.1128/aem.00299-14] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We constructed a library of in-frame deletion mutants targeting each gene in Pseudomonas aeruginosa PA14 predicted to participate in cyclic di-GMP (c-di-GMP) metabolism (biosynthesis or degradation) to provide a toolkit to assist investigators studying c-di-GMP-mediated regulation by this microbe. We present phenotypic assessments of each mutant, including biofilm formation, exopolysaccharide (EPS) production, swimming motility, swarming motility, and twitch motility, as a means to initially characterize these mutants and to demonstrate the potential utility of this library.
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14
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Fayeulle A, Veignie E, Slomianny C, Dewailly E, Munch JC, Rafin C. Energy-dependent uptake of benzo[a]pyrene and its cytoskeleton-dependent intracellular transport by the telluric fungus Fusarium solani. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2014; 21:3515-3523. [PMID: 24271730 DOI: 10.1007/s11356-013-2324-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 11/04/2013] [Indexed: 06/02/2023]
Abstract
In screening indigenous soil filamentous fungi for polycyclic aromatic hydrocarbons (PAHs) degradation, an isolate of the Fusarium solani was found to incorporate benzo[a]pyrene (BaP) into fungal hyphae before degradation and mineralization. The mechanisms involved in BaP uptake and intracellular transport remain unresolved. To address this, the incorporation of two PAHs, BaP, and phenanthrene (PHE) were studied in this fungus. The fungus incorporated more BaP into cells than PHE, despite the 400-fold higher aqueous solubility of PHE compared with BaP, indicating that PAH incorporation is not based on a simple diffusion mechanism. To identify the mechanism of BaP incorporation and transport, microscopic studies were undertaken with the fluorescence probes Congo Red, BODIPY®493/503, and FM®4-64, targeting different cell compartments respectively fungal cell walls, lipids, and endocytosis. The metabolic inhibitor sodium azide at 100 mM totally blocked BaP incorporation into fungal cells indicating an energy-requirement for PAH uptake into the mycelium. Cytochalasins also inhibited BaP uptake by the fungus and probably its intracellular transport into fungal hyphae. The perfect co-localization of BaP and BODIPY reveals that lipid bodies constitute the intracellular storage sites of BaP in F. solani. Our results demonstrate an energy-dependent uptake of BaP and its cytoskeleton-dependent intracellular transport by F. solani.
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Affiliation(s)
- Antoine Fayeulle
- Unité de Chimie Environnementale et Interactions sur le Vivant UCEIV EA 4492, ULCO, Dunkerque, 59140, France
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Abstract
Abstract Chitin is the most abundant natural aminopolysaccharide and serves as a structural component of extracellular matrices. It is found in fungal septa, spores, and cell walls, and in arthropod cuticles and peritrophic matrices, squid pens, mollusk shells, nematode egg shells, and some protozoan cyst walls. As prokaryotes, plants and vertebrates including humans do not produce chitin, its synthesis is considered as an attractive target site for fungicides, insecticides, and acaricides. Although no chitin synthesis inhibitor has been developed into a therapeutic drug to treat fungal infections in humans, a larger number of compounds have been successfully launched worldwide to combat arthropod pests in agriculture and forestry. This review summarizes the latest advances on the mode of action of chitin synthesis inhibitors with a special focus on those molecules that act on a postcatalytic step of chitin synthesis.
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Affiliation(s)
- Hans Merzendorfer
- Department of Biology/Chemistry, University of Osnabrück, 49069 Osnabrück, Germany.
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16
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Simmons WL, Daubenspeck JM, Osborne JD, Balish MF, Waites KB, Dybvig K. Type 1 and type 2 strains of Mycoplasma pneumoniae form different biofilms. MICROBIOLOGY-SGM 2013; 159:737-747. [PMID: 23412845 DOI: 10.1099/mic.0.064782-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Several mycoplasma species have been shown to form biofilms that confer resistance to antimicrobials and which may affect the host immune system, thus making treatment and eradication of the pathogens difficult. The present study shows that the biofilms formed by two strains of the human pathogen Mycoplasma pneumoniae differ quantitatively and qualitatively. Compared with strain UAB PO1, strain M129 grows well but forms biofilms that are less robust, with towers that are less smooth at the margins. A polysaccharide containing N-acetylglucosamine is secreted by M129 into the culture medium but found in tight association with the cells of UAB PO1. The polysaccharide may have a role in biofilm formation, contributing to differences in virulence, chronicity and treatment outcome between strains of M. pneumoniae. The UAB PO1 genome was found to be that of a type 2 strain of M. pneumoniae, whereas M129 is type 1. Examination of other M. pneumoniae isolates suggests that the robustness of the biofilm correlates with the strain type.
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Affiliation(s)
- Warren L Simmons
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - James M Daubenspeck
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - John D Osborne
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Mitchell F Balish
- Department of Microbiology, Miami University, Oxford, OH 45056-3619, USA
| | - Ken B Waites
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Kevin Dybvig
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.,Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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17
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Gilchrist KB, Garcia MC, Sobonya R, Lipke PN, Klotz SA. New features of invasive candidiasis in humans: amyloid formation by fungi and deposition of serum amyloid P component by the host. J Infect Dis 2012; 206:1473-8. [PMID: 22802434 DOI: 10.1093/infdis/jis464] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Invasive candidiasis occurs in the gastrointestinal tract, especially in neutropenic patients. We were interested in determining whether invasive fungi formed amyloid in humans as they are known to do in vitro. We also sought to characterize the consequence(s) of such amyloid formation. METHODS Tissue from 25 autopsy patients with invasive candidiasis of the gastrointestinal tract was stained with amyloidophilic dyes and for the presence of serum amyloid P component (SAP). Confirmation of the interaction of SAP and Candida was demonstrated using Candida albicans and mutants for amyloid formation. RESULTS Amyloid was present on the cellular surface of fungi invading gut tissue. Moreover, SAP bound to the fungal cell walls, confirming the presence of amyloid. In vitro observations showed SAP bound avidly to fungi when amyloid formed in fungal cell walls. An unexpected result was the lack of host neutrophils in response to the invading fungi, not only in neutropenic patients but also in patients with normal or increased white blood counts. CONCLUSIONS We report the first demonstration of functional fungal amyloid in human tissue and the binding of SAP to invading fungi. It is postulated that fungal amyloid, SAP, or a complex of the proteins may inhibit the neutrophil response.
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The mycelial response of the white-rot fungus, Schizophyllum commune to the biocontrol agent, Trichoderma viride. Fungal Biol 2011; 116:332-41. [PMID: 22289778 DOI: 10.1016/j.funbio.2011.12.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2011] [Revised: 12/13/2011] [Accepted: 12/14/2011] [Indexed: 11/22/2022]
Abstract
In this study, agar plate interaction between Schizophyllum commune and Trichoderma viride was investigated to characterise the physiological responses occurring during interspecific mycelial combat. The metabolite profiles and morphological changes in both fungi paired on agar were studied relative to the modulation of phenoloxidase activity in S. commune. The calcium ionophore A23187 was incorporated in self-paired cultures of S. commune to explore possible involvement of calcium influx in the response of S. commune to T. viride. The levels of lipid peroxides and protein carbonyls in the confronted mycelia of S. commune were also measured. Contact with T. viride induced pigmentation and cell wall hydrolysis in S. commune with concomitant increase in phenoloxidase activity, rise in the levels of oxidative stress indicators and increased levels of phenolic compounds, antioxidant γ-amino butyric acid, and pyridoxine and osmo-protective sugar alcohols. Calcium ionophore mimicked the pigmentation in the T. viride-confronted mycelia of S. commune, implicating calcium influx in the response to T. viride. The changes in S. commune are indicative of targeted responses to osmotic and oxidative stresses and phenoloxidase-mediated detoxification of noxious compounds in the contact interface with T. viride, which may confer resistance in natural environments.
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Response of Paracoccidioides brasiliensis Pb01 to stressor agents and cell wall osmoregulators. Fungal Biol 2011; 115:62-9. [DOI: 10.1016/j.funbio.2010.10.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Revised: 10/14/2010] [Accepted: 10/15/2010] [Indexed: 11/20/2022]
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Fang EF, Hassanien AAE, Wong JH, Bah CSF, Soliman SS, Ng TB. Purification and modes of antifungal action by Vicia faba cv. Egypt trypsin inhibitor. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010; 58:10729-35. [PMID: 20836498 DOI: 10.1021/jf102277k] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
A new 15 kDa Bowman-Birk type trypsin inhibitor (termed VFTI-E1) from fava beans (Vicia faba cv. Egypt 1) was isolated using liquid chromatography. Though it exhibited substantial homology in N-terminal amino acid sequence to other protease inhibitors, VFTI-E1 showed antiproteolytic activity against trypsin (K(i) 11.9 × 10(-9) M) but hardly any activity against chymotrypsin. It demonstrated antifungal activity toward the filamentous fungus Valsa mali with an IC(50) of 20 μM. The mechanism of its antifungal action toward V. mali included (1) induction of alteration of hyphal morphology, (2) growth inhibition by chitin deposition at hyphal tips, and (3) permeabilization of fungal membrane. The antifungal activity of VFTI-E1 was dependent on the ambient ionic strength as increasing concentrations of NaCl, CaCl(2), and MgCl(2) diminished the activity. The membranolytic action of VFTI-E1 was confined to fungus, but not exerted on human and rabbit erythrocytes. This study sheds light on the mode of hyphal growth inhibitory activity of protease inhibitors with antifungal activity. The antifungal activity of VFTI-E1 amplifies the scope of its potential applications.
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Affiliation(s)
- Evandro Fei Fang
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong, China
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Michels J, Büntzow M. Assessment of Congo red as a fluorescence marker for the exoskeleton of small crustaceans and the cuticle of polychaetes. J Microsc 2010; 238:95-101. [PMID: 20529057 DOI: 10.1111/j.1365-2818.2009.03360.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- J Michels
- Department of Functional Morphology and Biomechanics, Institute of Zoology, Christian-Albrechts-Universität zu Kiel, Germany.
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22
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Cellulose biosynthesis by the beta-proteobacterium, Chromobacterium violaceum. Curr Microbiol 2008; 57:469-76. [PMID: 18820969 DOI: 10.1007/s00284-008-9271-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2008] [Accepted: 06/30/2008] [Indexed: 10/21/2022]
Abstract
The Chromobacterium violaceum ATCC 12472 genome was sequenced by The Brazilian National Genome Project Consortium. Previous annotation reported the presence of cellulose biosynthesis genes in that genome. Analysis of these genes showed that, as observed in other bacteria, they are organized in two operons. In the present work, experimental evidences of the presence of cellulose in the extracellular matrix of the biofilm produced by C. violaceum in static cultures are shown. Biofilm samples were enzymatically digested by cellulase, releasing glucose units, suggesting the presence of cellulose as an extracellular matrix component. Fluorescence microscopy observations showed that C. violaceum produces a cellulase-sensitive extracellular matrix composed of fibers able to bind calcofluor. C. violaceum grows on medium containing Congo red, forming brown-red colonies. Together, these results suggest that cellulase-susceptible matrix material is cellulose. Scanning electronic microscopy analysis showed that the extracellular matrix exhibited a network of microfibrils, typical of bacterial cellulose. Although cellulose production is widely distributed between several bacterial species, including at least the groups of Gram-negative proteobacteria alpha and gamma, we give for the first time experimental evidence for cellulose production in beta-proteobacteria.
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Robert R, Pihet M. Conventional methods for the diagnosis of dermatophytosis. Mycopathologia 2008; 166:295-306. [PMID: 18478359 DOI: 10.1007/s11046-008-9106-3] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Revised: 01/15/2008] [Accepted: 01/30/2008] [Indexed: 10/22/2022]
Abstract
Dermatophytes are keratinolytic fungi responsible for a large variety of diseases that can affect glabrous skin, nails and hair. In many cases, the diagnosis is not clinically obvious, and mycological analysis is required. This includes both direct microscopic examination and cultures. First of all, clinical specimens have to be sampled according to localization and characteristics of the lesions. Direct microscopic examination is usually performed using clearing reagents (KOH or Amman's chloral-lactophenol), but its sensitivity may be greatly enhanced by the use of stains or fluorochromes such as Congo red or Calcofluor white. Histological analysis is an efficient method, but it is constraining for the patients and, as direct examination, it does not allow precise identification of the pathogen. Cultures are therefore needed, and specific culture media may be used to overcome the growth of rapidly growing contaminating moulds which may hamper the recovery of dermatophytes. Identification at the species level which may be useful to initiate an appropriate treatment or for setting prophylactic measures, relies on macroscopic and microscopic morphology. Subcultures on culture media which stimulate conidiation and, for some species, the production of pigments, are often necessary. Additionally, in case of atypical isolates, some biochemical or physiological tests may be performed such as the search for urease activity or the in vitro hair perforation test. However, their contribution to species identification is rather limited, and progress is still needed for the development of biochemical or immunological tests allowing an accurate identification at the species level, pending for the availability of molecular biology-based kits.
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Affiliation(s)
- Raymond Robert
- Laboratoire de Parasitologie-Mycologie, Faculté de Pharmacie, Groupe d'Etude des Interactions Hôte-Pathogène, UPRES-EA 3142, Université d'Angers, 16 boulevard Daviers, 49100 Angers, France.
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Simmons WL, Bolland JR, Daubenspeck JM, Dybvig K. A stochastic mechanism for biofilm formation by Mycoplasma pulmonis. J Bacteriol 2006; 189:1905-13. [PMID: 17142389 PMCID: PMC1855698 DOI: 10.1128/jb.01512-06] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Bacterial biofilms are communities of bacteria that are enclosed in an extracellular matrix. Within a biofilm the bacteria are protected from antimicrobials, environmental stresses, and immune responses from the host. Biofilms are often believed to have a highly developed organization that is derived from differential regulation of the genes that direct the synthesis of the extracellular matrix and the attachment to surfaces. The mycoplasmas have the smallest of the prokaryotic genomes and apparently lack complex gene-regulatory systems. We examined biofilm formation by Mycoplasma pulmonis and found it to be dependent on the length of the tandem repeat region of the variable surface antigen (Vsa) protein. Mycoplasmas that produced a short Vsa protein with few tandem repeats formed biofilms that attached to polystyrene and glass. Mycoplasmas that produced a long Vsa protein with many tandem repeats formed microcolonies that floated freely in the medium. The biofilms and the microcolonies contained an extracellular matrix which contained Vsa protein, lipid, DNA, and saccharide. As variation in the number of Vsa tandem repeats occurs by slipped-strand mispairing, the ability of the mycoplasmas to form a biofilm switches stochastically.
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Affiliation(s)
- Warren L Simmons
- Department of Genetics, University of Alabama at Birmingham, Birmingham AL 35294-0004, USA.
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Sutton DA, Slifkin M, Yakulis R, Rinaldi MG. U.S. case report of cerebral phaeohyphomycosis caused by Ramichloridium obovoideum (R. mackenziei): criteria for identification, therapy, and review of other known dematiaceous neurotropic taxa. J Clin Microbiol 1998; 36:708-15. [PMID: 9508300 PMCID: PMC104613 DOI: 10.1128/jcm.36.3.708-715.1998] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
We report a case of cerebral phaeohyphomycosis in a 36-year-old male caused by the neurotropic fungus Ramichloridium obovoideum (Matushima) de Hoog 1977 (Ramichloridium mackenziei Campbell et Al-Hedaithy 1993). This man resided in the Middle East, where the fungus appears to be endemic and, possibly, geographically restricted, since all previous reports of brain abscesses due to this organism have been for patients indigenous to this area. As a servant of the Saudi Arabian royal family, he appeared in the United States seeking treatment for chronic weight loss, fatigue, decreased memory, and a more recent 2-week history of right-hand weakness which worsened to involve the entire right upper extremity. On the day prior to his admission, he had a focal motor seizure with rotation of the head and eyes to the right, followed by secondary generalization. A computerized tomogram showed a ring-enhancing hypodense lesion in the left parietal subcortical region with associated edema and mass effect. Diagnosis of a fungal etiology was made following a parietal craniotomy and excisional biopsy by observation of septate, dematiaceous hyphal elements 2 to 3 microm in width on hematoxylin-and-eosin-stained sections from within areas of inflammation and necrosis. Culture of the excised material grew out a dematiaceous mould which was subsequently identified as R. obovoideum. At two months postsurgery and with a regimen of 200 mg of itraconazole twice a day, the patient was doing well and returned to Saudi Arabia. His condition subsequently deteriorated, however, and following a 7-month course of itraconzole, he expired. We use this case to alert clinicians and personnel in clinical mycology laboratories of the pathogenicity of this organism and its potential occurrence in patients with central nervous system signs and symptoms who have resided in the Middle East and to review and/or compare R. obovoideum with other neurotropic, dematiaceous taxa and similar nonneurotropic, dematiaceous species.
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Affiliation(s)
- D A Sutton
- Department of Pathology, University of Texas Health Science Center at San Antonio, 78284-7750, USA.
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Woods GL, Walker DH. Detection of infection or infectious agents by use of cytologic and histologic stains. Clin Microbiol Rev 1996; 9:382-404. [PMID: 8809467 PMCID: PMC172900 DOI: 10.1128/cmr.9.3.382] [Citation(s) in RCA: 105] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
A wide variety of stains are useful for detection of different organisms or, for viruses, the cytopathologic changes they induce, in smears prepared directly from clinical specimens and in tissue sections. Other types of stains, such as hematoxylin and eosin, are used routinely to stain tissue sections and are most valuable for assessing the immunologic response of the host to the invading pathogen. In many cases, the pattern of inflammation provides important clues to diagnosis and helps to guide the selection of additional "special" stains used predominantly for diagnosis of infectious diseases. A stain may be nonspecific, allowing detection of a spectrum of organisms, as do the Papanicolaou stain and silver impregnation methods, or detection of only a limited group of organisms, as do the different acid-fast techniques. Some nonspecific stains, such as the Gram stain, are differential and provide valuable preliminary information concerning identification. Immunohistochemical stains, on the other hand, are specific for a particular organism, although in some cases cross-reactions with other organisms occur. Despite the wealth of information that can be gleaned from a stained smear or section of tissue, however, the specific etiology of an infection often cannot be determined on the basis of only the morphology of the organisms seen; culture data are essential and must be considered in the final diagnosis.
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Affiliation(s)
- G L Woods
- Department of Pathology, University of Texas Medical Branch, Galveston, 77555-0743, USA
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Abstract
The etiologic agents of the dermatophytoses (ringworm) are classified in three anamorphic (asexual or imperfect) genera, Epidermophyton, Microsporum, and Trichophyton. Species capable of reproducing sexually belong in the teleomorphic genus, Arthroderma, of the Ascomycota. On the basis of primary habitat association, they may be grouped as geophilic (soil associated), zoophilic, and anthropophilic. Adaptation to growth on humans by most geophilic species resulted in diminished loss of sporulation, sexuality, and other soil-associated characteristics. The dermatophytes have the ability to invade keratinized tissue (skin, hair, and nails) but are usually restricted to the nonliving cornified layer of the epidermis because of their inability to penetrate viable tissue of an immunocompetent host. However, invasion does elicit a host response ranging from mild to severe. Acid proteinases, elastase, keratinases, and other proteinases reportedly act as virulence factors. The development of cell-mediated immunity correlated with delayed hypersensitivity and an inflammatory response is associated with clinical cure, whereas the lack of or a defective cell-mediated immunity predisposes the host to chronic or recurrent dermatophyte infection. Chronic dermatophytosis is mostly caused by Trichophyton rubrum, and there is some evidence that mannan produced by this fungus suppresses or diminishes the inflammatory response. Since dermatophytes cause a communicable disease, modes of transmission and control are discussed as well as a survey of recent trends in therapy. Collection of specimens, culture media, and tests for identification are also presented. Genetic studies have led to an understanding of incompatibility mechanisms, pleomorphism and variation, resistance to griseofulvin, and virulence. Molecular biology has contributed to our knowledge of the taxonomy and phylogenetic relationships of dermatophytes.
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Affiliation(s)
- I Weitzman
- Clinical Microbiology Service, Columbia Presbyterian Medical Center, New York, New York 10032-3784, USA
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Manafi M, Kneifel W, Bascomb S. Fluorogenic and chromogenic substrates used in bacterial diagnostics. Microbiol Rev 1991; 55:335-48. [PMID: 1943991 PMCID: PMC372823 DOI: 10.1128/mr.55.3.335-348.1991] [Citation(s) in RCA: 89] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Methods based on the application of chromogenic and fluorogenic substrates enable specific and rapid detection of a variety of bacterial enzymatic activities. By using these techniques, enzymatic reactions can be examined simultaneously or individually, either directly on the isolation plate or in cell suspensions. For this purpose, various testing principles and test kits for clinical and food microbiology have been introduced successfully during the last few years. In this paper we present a survey of different enzymes of microbial origin that are utilized for microbiological identification and differentiation and the corresponding methods. Particular emphasis is given to the examination of Escherichia coli and the description of the different techniques as used in routine analysis.
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Affiliation(s)
- M Manafi
- Hygiene Institute, University of Vienna, Austria
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HART RA, MO O, BORIUS F, FUNG D. COMPARATIVE ANALYSIS OF TRYPAN BLUE AGAR AND CONGO RED AGAR FOR THE ENUMERATION OF YEAST AND MOLD USING THE HGMF SYSTEM. J Food Saf 1990. [DOI: 10.1111/j.1745-4565.1990.tb00054.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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