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Incidence and clinical outcome of Cryptococcosis in a nation with advanced HIV surveillance program.The Aging Male : the Official Journal... Dec 2020Cryptococcosis is a major opportunistic invasive mycosis that mostly affects immunocompromised patients. (Observational Study)
Observational Study
BACKGROUND
Cryptococcosis is a major opportunistic invasive mycosis that mostly affects immunocompromised patients.
METHODS
This was an observational study of all culture-confirmed cases of cryptococcosis conducted in the State of Qatar from January 2005 to December 2016. Cryptococcus fungi were identified using Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS).
RESULTS
Fourteen culture-confirmed cases of cryptococcosis were identified during the study period. Four patients had a Human Immunodeficiency Virus (HIV) infection with low CD4 count and five were receiving immunosuppressant medications. The rest of the patients were apparently immuno-competent. The central nervous system was the most common site of infection (57%) followed by bloodstream infection (36%) and pneumonia (14%). One patient had a cryptococcal scrotal infection. Twelve isolates were Cryptococcus neoformans and 2 were Cryptococcus laurentii. All isolates were within the wild type ECV values to amphotericin B and fluconazole. Only 2 patients with bloodstream infection (HIV negative) died. The rest were cured of the infection.
CONCLUSION
Cryptococcosis is a rare fungal disease in the State of Qatar, mostly diagnosed in Asian immigrants. The central nervous system is the most common site of infection. The presence of the fungus in the blood carries a high mortality.
Topics: Antifungal Agents; Basidiomycota; Cryptococcosis; HIV Infections; Humans; Incidence
PubMed: 31741419
DOI: 10.1080/13685538.2019.1692198 -
The Brazilian Journal of Infectious... 2019Papiliotrema laurentii is one of several non-neoformans cryptococci that have rarely been associated with human infection, since it was previously considered saprophyte...
BACKGROUND
Papiliotrema laurentii is one of several non-neoformans cryptococci that have rarely been associated with human infection, since it was previously considered saprophyte and thought to be non-pathogenic to humans. Nevertheless, increasing number of reports of human infection have emerged in recent years, mostly in oncologic patients.
AIM
To report a case of a female patient with pyloric obstructive cancer with a catheter-related Papiliotrema laurentii blood stream infection and systematically review the available evidence on P. laurentii infection in humans.
METHODS
Retrieval of studies was based on Medical Subject Headings and Health Sciences Descriptors, which were combined using Boolean operators. Searches were run on the electronic databases Scopus, Web of Science, MEDLINE (PubMed), BIREME (Biblioteca Regional de Medicina), LILACS (Latin American and Caribbean Health Sciences Literature), Cochrane Library for Systematic Reviews and Opengray.eu. There was no language or date of publication restrictions. The reference lists of the studies retrieved were searched manually.
RESULTS
The search strategy retrieved 1703 references. In the final analysis, 31 references were included, with the description of 35 cases. Every patient but one had a previous co-morbidity - 48.4 % of patients had a neoplasm. Amphotericin B was the most used treatment and only a single case of resistance to it was reported. Most patients were cured of the infection.
CONCLUSION
P. laurentii infection in humans is usually associated to neoplasia and multiple co-morbidities, and amphotericin B seems to be a reliable agent for treatment.
Topics: Aged; Amphotericin B; Anti-Bacterial Agents; Bacteremia; Biopsy; Catheter-Related Infections; Cryptococcus; Female; Fluconazole; Humans; Piperacillin, Tazobactam Drug Combination; Stomach Neoplasms; Tomography, X-Ray Computed; Vancomycin
PubMed: 31738886
DOI: 10.1016/j.bjid.2019.10.005 -
Journal of Basic Microbiology Oct 2019Heavy metals such as lead, chromium, and metalloid like arsenic dominate the pinnacle in posing a threat to life. Being environment-friendly, elucidating the mechanism...
Heavy metals such as lead, chromium, and metalloid like arsenic dominate the pinnacle in posing a threat to life. Being environment-friendly, elucidating the mechanism by which microorganisms detoxify such elements has always been an active field of research hitherto. In the present study, we have investigated the capability of nitrogen-deprived Papiliotrema laurentii strain RY1 toward enhanced tolerance and neutralizing toxic elements. There were biosorption and bioprecipitation of lead and chromium at the cell surfaces. Bioprecipitation mechanisms included the formation of lead phosphates and pyromorphites from lead, grimaldite from chromium. Transcripts such as metallothionein, aquaporins, and arsenical pump-driving ATPase have been surmised to be involved in the detoxification of elements. Furthermore, activation of antioxidant defense mechanisms for the cells for each of the elements should contribute towards yeast's propagation. The efficiency of removal of elements for live cells and immobilized cells were high for lead and chromium. To the best of our knowledge, this is the first report of such high tolerance of lead, arsenic, and chromium for any yeast. The yeast showed such varied response under dual stress due to nitrogen starvation and in the presence of respective elements. The yeast possesses promising potentials in nitrogen deprived and enriched environments to aid in bioremediation sectors.
Topics: Antioxidants; Arsenic; Basidiomycota; Biodegradation, Environmental; Biological Transport; Cadmium; Environmental Pollutants; Gene Expression; Inactivation, Metabolic; Lead; Metallothionein; Metals, Heavy; Microbial Sensitivity Tests; Nitrogen
PubMed: 31430397
DOI: 10.1002/jobm.201900222 -
Carbohydrate Polymers Nov 2019Chitin deacetylase, an enzyme isolated from Cryptococcus laurentii RY1, catalyzes the hydrolysis of acetamido group of N-acetyl-D-glucosamine unit of chitin. The primary...
Chitin deacetylase, an enzyme isolated from Cryptococcus laurentii RY1, catalyzes the hydrolysis of acetamido group of N-acetyl-D-glucosamine unit of chitin. The primary objective of this study was to characterize and comprehend the activation of chitin deacetylase by DMSO. The secondary structure of the protein was determined by circular dichroism(CD).The interaction of protein with DMSO was evaluated by CD and tryptophan fluorescence spectroscopy which revealed that DMSO had no effect on overall secondary structure, but induced change in the tertiary structure of the enzyme. The interaction of chitin deacetylase with chitin in DMSO system when investigated by molecular dynamics simulation revealed stronger chitin deacetylase-chitin interaction involving several amino acid residues. The enhanced activity of the enzyme in presence of DMSO along with the fact that its k is highest of all other reported chitin deacetylases makes it a superior candidate in the industrial sector involved in chitosan production from chitin.
PubMed: 31426990
DOI: 10.1016/j.carbpol.2019.115032 -
Micron (Oxford, England : 1993) Sep 2019Stress response due to the lack of essential nutrient(s) for an organism has been a focal point of several scientific investigations. The present study investigates the...
Stress response due to the lack of essential nutrient(s) for an organism has been a focal point of several scientific investigations. The present study investigates the cellular adaptations behind the ability of Papiliotrema laurentii strain RY1 to perpetuate without added nitrogen and propagate robustly in growth- limiting amount of nitrogen. We executed phenotypic (using scanning electron microscopy, differential interference contrast microscopy and transmission electron microscopy), microbiological and computational analyses to show multiple responses of dimorphism, capsule formation and autophagy as a survival strategy by the yeast upon nitrogen starvation. The roles of phosphomannose isomerase, phosphomannomutase and several autophagy-related transcripts aiding in such a response have been discussed.
Topics: Adaptation, Physiological; Autophagy; Basidiomycota; Culture Media; Fungal Capsules; Hyphae; Microscopy, Electron, Scanning; Microscopy, Electron, Transmission; Nitrogen
PubMed: 31265985
DOI: 10.1016/j.micron.2019.102708