MyMedR

Displaying publications 21 - 28 of 28 in total

Abstract:

Sort:

Fulltext Intraspecific variation of the aquatic fungus Articulospora tetracladia: an ubiquitous perspective

Seena S, Duarte S, Pascoal C, Cássio F

PLoS One, 2012;7(4):e35884.
PMID: 22558256 DOI: 10.1371/journal.pone.0035884

The worldwide-distributed aquatic fungus Articulospora tetracladia Ingold is a dominant sporulating species in streams of the Northwest Iberian Peninsula. To elucidate the genetic diversity of A. tetracladia, we analyzed isolates collected from various types of plant litter or foam in streams from North and Central Portugal and North Spain, between 2000 and 2010. Genetic diversity of these fungal populations was assessed by denaturing gradient gel electrophoresis (DGGE) fingerprints and by using ITS1-5.8S-ITS2 barcodes. Moreover, ITS1-5.8S-ITS2 barcodes of A. tetracladia reported in other parts of the world (Central Europe, United Kingdom, Canada, Japan and Malaysia) were retrieved from the National Center for Biotechnology (NCBI) and the National Institute of Technology and Evaluation Biological Resource Center (NBRC) to probe into genetic diversity of A. tetracladia. PCR-DGGE of ITS2 region of 50 Iberian fungal isolates distinguished eight operational taxonomic units (OTUs), which were similar to those obtained from neighboring trees based on ITS2 gene sequences. On the other hand, ITS1-5.8S-ITS2 barcodes of 68 fungal isolates yielded nine OTUs, but five fungal isolates were not assigned to any of these OTUs. Molecular diversity was highest for OTU-8, which included only European isolates. Two haplotypes were observed within OTU-8 and OTU-9, while only one haplotype was found within each of the remaining OTUs. Malaysia did not share haplotypes with other countries. Overall results indicate that, apart from the Malaysian genotypes, A. tetracladia genotypes were geographically widespread irrespective of sampling time, sites or substrates. Furthermore, PCR-DGGE appeared to be a rapid tool for assessing intraspecific diversity of aquatic hyphomycetes.

Matched MeSH terms: Mitosporic Fungi/classification
Multiple rare opportunistic and pathogenic fungi in persistent foot skin infection

Chan GF, Sinniah S, Idris TI, Puad MS, Abd Rahman AZ

Pak J Biol Sci, 2013 Mar 01;16(5):208-18.
PMID: 24175430

Persistent superficial skin infection caused by multiple fungi is rarely reported. Recently, a number of fungi, both opportunistic and persistent in nature were isolated from the foot skin of a 24-year old male in Malaysia. The fungi were identified as Candida parapsilosis, Rhodotorula mucilaginosa, Phoma spp., Debaryomyces hansenii, Acremonium spp., Aureobasidium pullulans and Aspergillus spp., This is the first report on these opportunistic strains were co-isolated from a healthy individual who suffered from persistent foot skin infection which was diagnosed as athlete's foot for more than 12 years. Among the isolated fungi, C. parapsilosis has been an increasingly common cause of skin infections. R. mucilaginosa and D. hansenii were rarely reported in cases of skin infection. A. pullulans, an emerging fungal pathogen was also being isolated in this case. Interestingly, it was noted that C. parapsilosis, R. mucilaginosa, D. hansenii and A. pullulans are among the common halophiles and this suggests the association of halotolerant fungi in causing persistent superficial skin infection. This discovery will shed light on future research to explore on effective treatment for inhibition of pathogenic halophiles as well as to understand the interaction of multiple fungi in the progress of skin infection.

Matched MeSH terms: Fungi/classification
Rainforest Conversion to Rubber Plantation May Not Result in Lower Soil Diversity of Bacteria, Fungi, and Nematodes

Kerfahi D, Tripathi BM, Dong K, Go R, Adams JM

Microb Ecol, 2016 08;72(2):359-71.
PMID: 27221090 DOI: 10.1007/s00248-016-0790-0

Large areas of rainforest in Asia have been converted to plantations, with uncertain effects on soil biodiversity. Using standard metagenetic methods, we compared the soil biota of bacteria, fungi, and nematodes at three rainforest sites in Malaysia with two rubber plantation sites with similar soils and geology. We predicted the following: (1) that the rubber sites would have a lower α- and β-diversity than the rainforest sites, due to the monospecific canopy cover and intensive management with herbicides, pesticides, and fertilizers, and (2) that due to differences in the physical and biotic environment associated with cultivation, there would be distinct communities of bacteria, fungi, and nematodes. However, regarding (1), the results showed no consistent difference in α- and β-diversity of bacteria, fungi, or nematodes between rainforest and rubber plantation sites. It appears that conversion of rainforest to rubber plantations does not necessarily result in a decrease in diversity of soil biota. It may be that heterogeneity associated with the cultivation regimen compensates for loss of biotically imposed heterogeneity of the original rainforest. Regarding (2), as predicted there were statistically significant differences in community composition between rainforest and rubber plantation for bacteria, fungi, and nematodes. These differences could be related to a range of factors including light level, litter fall composition, pH, C and N, selecting a distinct set of soil taxa, and it is possible that this in itself would affect long-term soil function.

Matched MeSH terms: Fungi/classification*
Fulltext Bacterial and fungal endophthalmitis in upper Egypt: related species and risk factors

Gharamah AA, Moharram AM, Ismail MA, Al-Hussaini AK

Asian Pac J Trop Biomed, 2012 Aug;2(8):655-9.
PMID: 23569989 DOI: 10.1016/S2221-1691(12)60115-4

To study risk factors, contributing factors of bacterial and fungal endophthalmitis in Upper Egypt, test the isolated species sensitive to some therapeutic agents, and to investigate the air-borne bacteria and fungi in opthalmology operating rooms.

Matched MeSH terms: Fungi/classification
Screening antimicrobial activity of various extracts of Urtica dioica

Modarresi-Chahardehi A, Ibrahim D, Fariza-Sulaiman S, Mousavi L

Rev. Biol. Trop., 2012 Dec;60(4):1567-76.
PMID: 23342511

Urtica dioica or stinging nettle is traditionally used as an herbal medicine in Western Asia. The current study represents the investigation of antimicrobial activity of U. dioica from nine crude extracts that were prepared using different organic solvents, obtained from two extraction methods: the Soxhlet extractor (Method I), which included the use of four solvents with ethyl acetate and hexane, or the sequential partitions (Method II) with a five solvent system (butanol). The antibacterial and antifungal activities of crude extracts were tested against 28 bacteria, three yeast strains and seven fungal isolates by the disc diffusion and broth dilution methods. Amoxicillin was used as positive control for bacteria strains, vancomycin for Streptococcus sp., miconazole nitrate (30 microg/mL) as positive control for fungi and yeast, and pure methanol (v/v) as negative control. The disc diffusion assay was used to determine the sensitivity of the samples, whilst the broth dilution method was used for the determination of the minimal inhibition concentration (MIC). The ethyl acetate and hexane extract from extraction method I (EA I and HE I) exhibited highest inhibition against some pathogenic bacteria such as Bacillus cereus, MRSA and Vibrio parahaemolyticus. A selection of extracts that showed some activity was further tested for the MIC and minimal bactericidal concentrations (MBC). MIC values of Bacillus subtilis and Methicillin-resistant Staphylococcus aureus (MRSA) using butanol extract of extraction method II (BE II) were 8.33 and 16.33mg/mL, respectively; while the MIC value using ethyl acetate extract of extraction method II (EAE II) for Vibrio parahaemolyticus was 0.13mg/mL. Our study showed that 47.06% of extracts inhibited Gram-negative (8 out of 17), and 63.63% of extracts also inhibited Gram-positive bacteria (7 out of 11); besides, statistically the frequency of antimicrobial activity was 13.45% (35 out of 342) which in this among 21.71% belongs to antimicrobial activity extracts from extraction method I (33 out of 152 of crude extracts) and 6.82% from extraction method II (13 out of 190 of crude extracts). However, crude extracts from method I exhibited better antimicrobial activity against the Gram-positive bacteria than the Gram-negative bacteria. The positive results on medicinal plants screening for antibacterial activity constitutes primary information for further phytochemical and pharmacological studies. Therefore, the extracts could be suitable as antimicrobial agents in pharmaceutical and food industry.

Matched MeSH terms: Fungi/classification
Application of rDNA-PCR amplification and DGGE fingerprinting for detection of microbial diversity in a Malaysian crude oil

Liew PW, Jong BC

J Microbiol Biotechnol, 2008 May;18(5):815-20.
PMID: 18633276

Two culture-independent methods, namely ribosomal DNA libraries and denaturing gradient gel electrophoresis (DGGE), were adopted to examine the microbial community of a Malaysian light crude oil. In this study, both 16S and 18S rDNAs were PCR-amplified from bulk DNA of crude oil samples, cloned, and sequenced. Analyses of restriction fragment length polymorphism (RFLP) and phylogenetics clustered the 16S and 18S rDNA sequences into seven and six groups, respectively. The ribosomal DNA sequences obtained showed sequence similarity between 90 to 100% to those available in the GenBank database. The closest relatives documented for the 16S rDNAs include member species of Thermoincola and Rhodopseudomonas, whereas the closest fungal relatives include Acremonium, Ceriporiopsis, Xeromyces, Lecythophora, and Candida. Others were affiliated to uncultured bacteria and uncultured ascomycete. The 16S rDNA library demonstrated predomination by a single uncultured bacterial type by >80% relative abundance. The predomination was confirmed by DGGE analysis.

Matched MeSH terms: Fungi/classification
Fulltext Point prevalence surveys of health-care-associated infections: a systematic review

Saleem Z, Godman B, Hassali MA, Hashmi FK, Azhar F, Rehman IU

Pathog Glob Health, 2019 Jun;113(4):191-205.
PMID: 31215326 DOI: 10.1080/20477724.2019.1632070

Health-care-associated infections (HAIs) are considered a serious public health issues that contribute substantially to the global burden of mortality and morbidity with respect to infectious diseases. The aim is to assess the burden of health-care-associated infections by collation of available data from published point prevalence surveys (PPS) on HAIs to give future guidance. Study protocol and methodology were designed according to preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines. Published research papers that conducted a point prevalence survey of HAIs in hospital settings by following the structured survey methodology employed by European Centre of Disease Prevention and Control (ECDC) were included. Of 1212 articles, 67 studies were included in the final analysis conducted across different countries. Overall, 35 studies were conducted in Europe, 21 in Asia, 9 in America, and 2 in Africa. The highest prevalence of HAIs was recorded in a study conducted in adult ICU settings of 75 regions of Europe (51.3%). The majority of the studies included HAI data on urinary tract infections, respiratory tract infections, and bloodstream infections. Klebsiella pneumonia, Pseudomonas aeruginosa and E. coli were the most frequent pathogens responsible for HAIs. PPS is an useful tool to quantify HAIs and provides a robust baseline data for policymakers. However, a standardize surveillance method is required. In order to minimize the burden of HAIs, infection prevention and control programs and antibiotic stewardship may be effective strategies to minimize the risk of HAIs.

Matched MeSH terms: Fungi/classification
Fulltext BACE1 inhibitory activity of fungal endophytic extracts from Malaysian medicinal plants

Harun A, James RM, Lim SM, Abdul Majeed AB, Cole AL, Ramasamy K

BMC Complement Altern Med, 2011 Sep 24;11:79.
PMID: 21943123 DOI: 10.1186/1472-6882-11-79

BACKGROUND: BACE1 was found to be the major β-secretase in neurons and its appearance and activity were found to be elevated in the brains of AD patients. Fungal endophytic extracts for BACE1 inhibitory activity and cytotoxicity against PC-12 (a rat pheochromocytoma with neuronal properties) and WRL68 (a non-tumorigenic human hepatic) were investigated.
METHODS: Endophytes were isolated from plants collected from Kuala Pilah, Negeri Sembilan and the National Park, Pahang and the extracts were tested for BACE1 inhibition. For investigation of biological activity, the pure endophytic cultures were cultivated for 14 days on PDA plates at 28°C and underwent semipolar extraction with ethyl acetate.
RESULTS: Of 212 endophytic extracts (1000 μg/ml), 29 exhibited more than 90% inhibition of BACE1 in the preliminary screening. Four extracts from isolates HAB16R13, HAB16R14, HAB16R18 and HAB8R24 identified as Cytospora rhizophorae were the most active with IC(50(BACE1)) values of less than 3.0 μg/ml. The most active extract HAB16R13 was shown to non-competitively inhibit BACE1 with K(i) value of 10.0 μg/ml. HAB16R13 was considered non-potent against PC-12 and WRL68 (IC(50(CT))) of 60.0 and 40.0 μg/ml, respectively).
CONCLUSIONS: This first report on endophytic fungal extract with good BACE1 inhibitory activity demonstrates that more extensive study is required to uncover the potential of endophytes.

Matched MeSH terms: Fungi/classification