جستجوی مقالات مرتبط با کلیدواژه « maldi-tof ms » در نشریات گروه « پزشکی »

Leeches have been used to complement medical therapies for many years, however there is little data on the microorganisms they may harbor as part of their flora. The study aims were to (1) identify the presence of bacteria and (2) the presence of Hepatitis B and C viruses (HBV and HCV) in medicinal leeches using traditional bacteriological assays, Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) and quantitative PCR (qPCR). Samples obtained from the body surface, intestine, and jaws from 10 Hirudo verbana leeches were aseptically cultured using traditional microbiological assays. Bacterial isolates were identified using the MALDI-TOF technique and the presence of HBV and HCV was analyzed using qPCR. The primary bacterium isolated from the sampled leeches were Aeromonas veronii (A. veronii) which was isolated from the jaws, gut and body surface of all leeches. Other bacteria isolated at a lower frequency from various parts were Chryseobacterium gleum, Ochrobactrum anthropi, Moraxella osloensis, Microbacterium oxydans, Kytococcus sedentarius, Rhizobium radiobacter, Staphylococcus hominis, Citrobacter and Bacillus. No anaerobic bacteria or hepatitis viruses were detected. Interestingly, some of the bacterial species identified in this study have been implicated in hospital acquired infections and are of particular risk to immunocompromised patients. The recovery of potential human pathogens from within medicinal leeches is a public health concern and consequently their use should be restricted and avoided in susceptible individuals or a prophylactic treatment should be applied.

The outbreak of novel coronavirus (2019-nCoV), which began in Wuhan, China, has rapidly spread in many countries and is currently considered a pandemic. The virus (SARS-CoV-2) causes severe acute respiratory syndrome and is related to SARS-CoV and MERS-CoV.

In this review, an introduction to SARS-CoV-2 was provided comprising the following items: general features; pathogenesis; the existing knowledge on immunological properties; transmission routs; diagnostic features, especially discussion about new approaches for treatment and prevention; and different diagnostic methods including nucleic acid based assays, serological testing, and MALDI TOF-MS and LC-MS technologies.

Introducing the different methods for SARS-CoV-2 detection may be useful to provide new insights into the development and improvement of detection primers, probes, methods/techniques, potential targets for drug designation, and therapeutic candidates against the virus.

Liver cancer is the third rank amongst the common malignancies, causing maximum death in the patients diagnosed with cancers. Currently available biomarkers are not enough sensitive for early diagnosis of hepatocellular carcinoma (HCC). This makes difficult management of HCC. With the aim of finding new generation of proteomic-based biomarkers, the represented study was designed to characterize the differentially expressed proteins at different stages of HCC initiation and at progression. This could lead to find potential biomarkers for early detection of HCC.

In this experimental study, we report induction of HCC by administrating chemical carcinogens in male Wistar rats. Disease progression was monitored by histological evaluation. Serum proteomic analyses such as 2 dimensional (2D)-electrophoresis, MALDI-TOF-MS/MS and Western blot have been used to analyze and characterize the differentially expressed proteins during HCC development.

HCC initiation and tumorigenesis were observed at one and four months post carcinogen treatment, respectively. One of the differentially-expressed proteins, namely, cytosolic phospholipase A2 delta was significantly up-regulated at very early stage of HCC development. Its expression continued to increase during cancer progression and hepatotumorigenesis stages. Its elevated expression has been confirmed by Western blot analysis. Consistent to this, analyses of the sera in the clinically confirmed liver cancer patients showed elevated expression of this protein, further validating our experimental results.

This study suggests that elevation in the expression of cytosolic phospholipase A2 delta is associated with progression of HCC.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is widely used to discriminate among pathogenic microorganisms in clinical laboratories. The aim of this study was to assess the utility of MALDI-TOF MS in the routine identification of clinical dermatophyte isolates obtained from various geographical regions of Iran.

A total of 94 isolates, including Trichophyton interdigitale (n=44), T. rubrum (n=40), T. tonsurans (n=4), Microsporum canis (n=4), and Epidermophyton floccosum (n=1), were analyzed in this study. The identity of each isolate was determined by polymerase chani reaction amplification and sequencing of the internal transcribed spacer (ITS) region of nuclear-encoded ribosomal DNA and also MALDI-TOF MS. The obtained data by molecular approach were compared with MALDI-TOF MS.

The MALDI-TOF MS led to the identification of 44 (47%) isolates at the species level by generating the spectral score values of ≥ 2.0. However, there was not sufficient agreement between the results of the molecular-based ITS identification methods and MALDI-TOF MS in the species identification of 16 (17%) isolates. The Bruker Daltonics database was also not able to identify protein spectra related to 12 isolates (13%), including T. interdigitale (n=5), T. rubrum (n=4), M. canis (n=2), and T. tonsurans (n=1).

According to the results, the utility of MALDI-TOF MS as a routine diagnostic tool for the accurate and reliable identification of dermatophytes can be justified whenever the protein spectra of a large set of worldwide clinical isolates are included in the commercial libraries. In addition, MALDI-TOF MS can be alternatively used to construct an in-house reference database.

Background and PurposeVulvovaginal candidiasis (VVC) is a common problem in women. The purpose of this study was to identify of Candida species isolated from vulvovaginitis woman suffering vulvovaginitis refered to Ghaem Hospital, Mashhad, Iran, by use of MALDI-TOF mass spectrometry.
Materials and MethodsThe 65 clinical samples isolated from Vulvovaginitis women were collected in Ghaem Hospital. All specimens were identified using phenotypic techniques such as microscopy and culture on Sabouraud dextrose agar and corn meal agar medium,Then, All isolates were detected and were processed for MALDI TOF MS identification.
Results Of the 65 isolates analyzed, 61 (93.8%) were recognised by MALDI-TOF mass spectrometry and for four isolates (6.1%) only not relabile identifications were achieved. In this study, the most frequently isolated species were Candida albicans (58.5%), followed by Candida tropicalis (16.9%), Candida glabrata (7.7%), Candida parapsilosis (7.7%) and Candida guillermondii (3.1%).
Conclusionpresented results demonstrate that the MALDI TOF mass spectrometry is a fast and reliable technique, and has the potential to replace conventional phenotypic identification of Candida species and other yeast strains routinely isolated in clinical microbiology laboratories.

Extreme ecosystems can be a source of untapped micro-organisms able to produce novel bioactive compounds of industrial interest. Consequently, in this work, 32 Actinomycetes were isolated from 6 soil samples collected from Algerian Sahara in searching for untapped producers of novel antimicrobial compounds. All the isolates were further subjected to antimicrobial screening against pathogenic bacteria, yeast and fungi. The obtained results indicated that three of the isolates (named C, MS1 and 10) showed antimicrobial activities against most of the tested pathogenic micro-organisms. Therefore, these three promising isolates, previously identified as Streptomyces by morphological, biochemical and physiological methods, were selected for their subsequent identification by the whole cell matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) analysis. Thus, the isolates C, MS1 and 10 were identified as Streptomyces violaceoruber B263 UFL, Streptomyces albus B262 UFL, and Streptomyces badius B192 UFL, respectively. These results pointed out Actinomycetes from Sahara soils as potential sources of novel antimicrobial compounds. Also, MALDI-TOF MS showed to be a robust technique for bacteria identification.