Journal of Medical Microbiology (J MED MICROBIOL )

Publisher: Pathological Society of Great Britain and Ireland, Society for General Microbiology

Description

The Journal of Medical Microbiology aims to maintain and enhance its high-quality comprehensive coverage of pathogenic micro-organisms and their diseases from research, clinical, and diagnostic points of view. Each issue contains up-to-the-minute editorials, in-depth review articles, original papers presenting research findings, and brief reports and technical notes.

  • Impact factor
    2.30
    Show impact factor history
     
    Impact factor
  • 5-year impact
    2.64
  • Cited half-life
    6.60
  • Immediacy index
    0.52
  • Eigenfactor
    0.02
  • Article influence
    0.82
  • Website
    Journal of Medical Microbiology website
  • Other titles
    Journal of medical microbiology (Online)
  • ISSN
    0022-2615
  • OCLC
    37788051
  • Material type
    Document, Periodical, Internet resource
  • Document type
    Internet Resource, Computer File, Journal / Magazine / Newspaper

Publisher details

Society for General Microbiology

  • Pre-print
    • Author can archive a pre-print version
  • Post-print
    • Author cannot archive a post-print version
  • Restrictions
    • 12 months embargo
  • Conditions
    • On institutional repository or open access repository
    • Published source must be acknowledged
    • Version deposited must replicate that accepted for publication (authors version)
    • Set phrase to accompany archived copy (see policy)
    • Publisher's version/PDF cannot be used
    • Publisher last contacted on 29/08/2014
  • Classification
    ​ yellow

Publications in this journal

  • [Show abstract] [Hide abstract]
    ABSTRACT: HPV16 genome integration into the host chromosome is a crucial event during viral life cycle and a major step towards carcinogenesis. The integration of HPV16 DNA promotes a constitutive high expression level of E6 and E7 oncoproteins, resulting to the extensive proliferation of the infected epithelial cells. The present report studied the physical status of HPV16 genome, through determination of E1/E6 and E2/E6 DNA copy number ratios in sixty one cervical samples of low and high grade malignancy and eight cervical cancer samples, all of them associated with HPV16 infection. The selection of E1, E2 and E6 amplification target regions was performed according to the most prevalent deleted/disrupted sites of E1 and E2 genes. For this target selection we also considered the most conserved regions of E1, E2 and E6 genes among the same HPV16 isolates that were recently reported by our group. The analysis of HPV16 DNA form revealed a significant association among the mixed DNA forms in low grade and high grade malignancies, (x2, P < 0.01). The comparative analysis of E1/E6 and E2/E6 in the same cervical samples provides an accurate picture of HPV16 DNA form and may reveal whether different HPV16 DNA integrants coexist in the same cervical sample or not. This study proposes that E1/E6 and E2/E6 ratios determine with accuracy the HPV16 DNA integration pattern and may predict multiple integration events in the examined sample, thus providing significant information about the progression of cervical dysplasia.
    Journal of Medical Microbiology 09/2014;
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    ABSTRACT: Antimicrobial susceptibility testing with the BD Phoenix system on bacterial cell pellets generated from blood culture broths using the Bruker MALDI Sepsityper kit was evaluated. Seventy-six Gram negative isolates, including 12 with defined multi-resistant phenotypes, had antibiotic susceptibility testing (AST) performed by Phoenix on the cell pellet in parallel with conventional methods. In total, 1414/1444 (97.9%) susceptibility tests were concordant, with only 1 (0.07%) very major error. This novel method has the potential to reduce the turn-around-time for AST results by up to a day for Gram negative bacteraemias.
    Journal of Medical Microbiology 09/2014;
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    ABSTRACT: Data on in vitro susceptibility testing of echinocandins against Aspergillus species are sparse. The objective of this study was to describe the phenotypes of A. flavus when exposed in vitro to caspofungin and to test whether they were associated to genotype. The caspofungin MICs of 37 A. flavus clinical isolates collected from13 patients with invasive aspergillosis where determined using the Etest assay. The caspofungin MICs ranged from 0.012 to 0.064 mg/L; modal MIC was 0.023 mg/L; the MIC50 and MIC90 where 0.032 and 0.064 mg/L, respectively. A clear end point was noted in 24 (65%) isolates, whereas 7 (19%) displayed a trailing effect and 6 (16%) a paradoxical growth when exposed to caspofungin. In these A. flavus isolates, the absence of significant population structure or genetic differentiation indicated that trailing or paradoxical growth phenotypes were independent from microsatellite genotype.
    Journal of Medical Microbiology 09/2014;
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    ABSTRACT: This study aimed at identifying strains of the C. parapsilosis complex isolated from animals, as well as to assess their in vitro antifungal susceptibility profile and in vitro production of virulence attributes. We used 28 isolates of C. parapsilosis (sensu lato) recovered from clinically healthy animals. The strains were phenotypically characterized, followed by molecular identification of the species through PCR-Restriction Enzyme Analysis. Then, the susceptibility of the strains to amphotericin B, itraconazole, voriconazole, fluconazole and caspofungin was assessed through broth microdilution, according to CLSI (M27-A3). Additionally, the ability of the strains to produce biofilm, phospholipases and proteases was analyzed. Molecular analysis showed thirteen C. parapsilosis (sensu stricto), ten C. orthopsilosis and five C. metapsilosis strains. In vitro resistance to fluconazole was observed in three strains of C. parapsilosis (sensu stricto) and two C. metapsilosis. All tested strains were able to form biofilms, 23/28 isolates presented protease production, while none were able to produce phospholipases. Our study shows that C. parapsilosis sensu stricto and C. orthopsilosis are the most common species of the C. parapsilosis species complex and that these cryptic species present no significant phenotypical differences.
    Journal of Medical Microbiology 09/2014;
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    ABSTRACT: Vulvovaginal candidiasis (VVC) is one of the most common causes of vaginitis and affects about 75% of women of reproductive age. In order to better understand the epidemiology and pathogenesis of this disease, we evaluated genetic relatedness among 62 clinical isolates of Candida albicans sequentially obtained from the anus and vagina of patients with sporadic and recurrent VVC. Evaluation of patient's demographic and clinical data, direct examination and colony forming units (CFU) counts of vaginal and anal samples were also performed. The genotypes of strains were determined with ABC genotyping and Randomly Amplified Polymorphic DNA (RAPD). Genotype A was the most prevalent (93.6%), followed by genotype C (6.4%), whereas genotype B was not found. We found the maintenance of the same ABC genotype, regardless of the body site of each patient. Most of the vaginal strains suffered microevolution, whereas most of the anal strains were replaced during the period of study. Vaginal and anal isolates of C. albicans obtained simultaneously from the same patient showed the same ABC genotype and high genetic similarity as determined by RAPD. Genotype A seems to be dominant in both vaginal and anal isolates of patients with VVC. Our results corroborate with the hypothesis that there are "substrains" of the C. albicans vaginal clone successfully established, which dominates in an apparently random manner in the course of time. It is suggested that the anal reservoir constitutes a possible source for vaginal infection in most of the cases.
    Journal of Medical Microbiology 09/2014;
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    ABSTRACT: Detection of latent Mycobacterium tuberculosis (Mtb) is a challenge in the diagnosis of asymptomatic, sub-clinical tuberculosis (TB). We report the development of an immunofluorescence technique to visualize and enumerate Mtb in latently-infected rabbit lungs, where no acid fast stained organisms were seen and no cultivable bacilli were obtained by conventional staining and agar-plating methods.
    Journal of Medical Microbiology 08/2014;
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    ABSTRACT: Aim of this study was to compare the performance of serological versus molecular typing methods to detect capsular polysaccharide (CP) and surface-associated polysaccharide antigen 336 phenotypes of Staphylococcus aureus isolates. Molecular typing of CP types 1, 5 and 8 was carried out using PCR whereas serological typing of CP1, 2, 5, 8 and antigen 336 was carried out by slide agglutination using specific antisera. By genotyping, 14/31 strains were CP8 positive, 12/31 strains were CP5 and the remaining 6/31 isolates were non-typeable (NT). One isolate was positive for both CP5 and CP8 by PCR but was confirmed as CP8 type serologically. Detection of CP2 and type 336 by PCR was not possible because specific primers were either not available or were non-specific. Using serotyping, 14/31 strains were CP8 positive, 11/31 CP5 positive and 2/31 positive for antigen 336. The remaining four S. aureus isolates were serologically NT. However, three of 4 NT and two 336-positive S. aureus isolates were encapsulated as determined by light microscopy after capsular staining. This discovery was surprising and warrants further investigations on the identification and characterisation of additional capsular phenotypes prevalent among S. aureus clinical isolates. It was concluded that serological typing was a better method than molecular typing method for use in epidemiological investigations based upon the distribution of surface-associated polysaccharide antigens-based phenotypes.
    Journal of Medical Microbiology 08/2014;
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    ABSTRACT: The field of medical microbiology was born in the late 19th century. Robert Koch, Joseph Lister, Louis Pasteur, and others were responsible for the classic work that forms the foundation of much of today's science. This work is often taught to students today as perfectly formed ideas and experiments, without the relevant historical context. Yet science was as much a competitive and collaborative enterprise during the time of Pasteur as it is today. Therefore, to fully appreciate the contributions made by the founding fathers of our field, one must examine their work in its historical context. In this spirit, here we summarize a report made by Pasteur and Jules François Joubert to the French Academy of Sciences in 1877 titled "Charbon et septicémie" (Anthrax and septicemia) (Pasteur & Joubert, 1877).
    Journal of Medical Microbiology 08/2014;
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    ABSTRACT: In this study species diversity of staphylococci with inducible resistance to macrolides, lincosamides and streptogramin B (MLSB) isolated from clinical samples, sewage and river water was investigated. Inducible clindamycin-resistance was tested using D-test and macrodilution-assays. Inducible cross-resistance (iMLSB-phenotype) was examined by PCR of erm gene classes A, B, C, F, G, Q, T and 43. Although ermC was the most frequently detected resistance gene in iMLSB-phenotypes of environmental staphylococci (61.2 %) resistance genes encoding for iMLSB were more diverse than in staphylococci from hospital samples. In 22.4 % of iMLSB-staphylococci from aquatic environments none of the eight tested erm genes was found. Those isolates and erm43 expressing Staphylococcus lentus displayed low erythromycin-MICs (3-16 μg ml-1) compared to ermC-positive environmental staphylococci (≥ 256 μg ml-1). Contrary to clinical isolates with clearly defined resistance behavior, resistance patterns against MLSB and MICs for clindamycin of environmental isolates were more divers. Although the abundance of iMLSB-staphylococci in the aquatic environment was lower than in staphylococci from hospital samples, the diversity of resistance genes encoding for this phenotype seemed to be higher. Oleandomycin is the best marker to correlate iMLSB-phenotype and the respective erm gene. The phenotypical behavior of environmental isolates may differ from the resistance pattern of clinical iMLSB-staphylococci expressing ermA or ermC, and this should be considered for successful treatment of infections.
    Journal of Medical Microbiology 08/2014;
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    ABSTRACT: The purpose of this review is to discuss the scientific literature on waterborne healthcare-associated infections (HCAI) published from 1990 to 2012. The revision focuses on the aquatic bacteria and describes both outbreaks and single cases in relation to patients characteristics, settings, and contaminated sources. An overview of diagnostic methods and environmental investigations is summarized in order to provide guidance for future case investigations. Lastly, on the basis of prevention and control measures adopted, information and recommendations are given. A total of 125 reports were included, 41 of them describing hospitalized children. All cases were sustained by opportunistic pathogens, mainly Legionellaceae, Pseudomonadaceae and Burkholderiaceae. Hot water distribution systems were the primary source of Legionnaires' disease, bottled water was mainly colonized by Pseudomonaceae, and Burkholderiaceae were the leading cause of distilled and sterile water contamination. Intensive care unit was the most frequently involved setting but patient characteristics are the main risk factor, independently of the ward. As the microbes water contamination is difficult to be avoided and disinfection treatments may be insufficient to control the risk of infection, a proactive preventive plan should be put in place. Nursing staff should pay special attention to children and immunosuppressed patients to avoid tap water exposure, also for their personal hygiene, and to regularly use sterile water for rinsing/cleaning devices.
    Journal of Medical Microbiology 08/2014;
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    ABSTRACT: Staphylococcus epidermidis is the most commonly isolated etiological agent of nosocomial infections mainly due to its ability to establish biofilms on indwelling medical devices. Detachment of bacteria from S. epidermidis biofilms and subsequent growth in the planktonic form is a hallmark in the pathogenesis of these infections leading to dissemination. Here we showed that S. epidermidis cells collected from biofilms cultured in conditions that promote cell viability present marked changes in their physiological status upon initiating a planktonic mode of growth. When compared to cells growing in biofilms, they displayed an increased SYBR green I staining intensity, increased transcription of the rpiA gene, decreased transcription of icaA gene as well as higher susceptibility to vancomycin and penicillin antibiotics. When bacteria collected from biofilms with high proportions of dormant cells were subsequently cultured in the planktonic mode, a large proportion of cells maintained a low SYBR staining intensity and increased resistance to vancomycin and penicillin, a profile typical of dormant cells. This phenotype further associated with a decreased ability of these biofilm-derived cells to induce the production of pro-inflammatory cytokines by bone marrow-derived dendritic cells in vitro, as determined by pro-inflammatory cytokine quantification. These results demonstrated that cells detached from the biofilm maintain a dormant cell-like phenotype, having a low pro-inflammatory effect and decreased susceptibility to antibiotics suggesting these cells may contribute for the recalcitrant nature of biofilm infections.
    Journal of Medical Microbiology 07/2014;
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    ABSTRACT: The aim of the study was to investigate the association between the presence of altered PBP3 in non-typeable Haemophilus influenzae (NTHi) and an increased capacity to invade bronchial epithelial cells in vitro. A collection of 40 clinical isolates of NTHi comprised of 20 with normal penicillin binding protein 3 (PBP3) and 20 with altered PBP3 (defined by an N526K substitution) was established. The isolates were tested for the ability to invade bronchial epithelial cells in vitro using a 4h gentamicin survival assay. Invasion was measured as the percentage of intracellular organisms relative to the initial inoculum. The mean invasion rate ranged from 0.00% to 14.79% in the normal PBP3 isolates and 0.02% to 36.69% in the altered PBP3 isolates. The altered PBP3 isolates had a higher (p = 0.003) mean invasion rate (6.86%, n = 20) than the normal PBP3 isolates (1.31%, n = 20). Subsequently, 2 variants of altered PBP3 (transformant 1 - N526K, transformant 2 - M377I, S385T, L389F and N526K) were cloned into 3 of the initial isolates (parents) with normal PBP3 and relatively low invasive ability, and the parents and transformants tested for invasion as above. There was no difference (p = 0.89) in the mean invasion rates for the parents (0.81%, n=3), transformants 1 (0.90%, n=3) and transformants 2 (1.38%, n=3). There is an association between the presence of altered PBP3 in NTHi and an increased capacity to invade BEAS-2B cells in vitro, but cloning experiments suggest that the altered PBP3 is not directly involved in enhanced invasion.
    Journal of Medical Microbiology 07/2014;
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    ABSTRACT: Group B Streptococcus (GBS) is a commensal bacterium of the human gastrointestinal and genital tracts. It is a leading cause for neonatal sepsis and meningitis and has also been recognized as an important pathogen in pregnant women and the elderly. We investigated mechanisms of macrolides and tetracycline resistance in GBS colonizing women in Egypt. A total of 100 isolates were screened with standard antibiotic susceptibility tests. A multiplex PCR assay was utilized to detect macrolide and tetracycline resistance determinants. All isolates were uniformly susceptible to penicillin G, ampicillin, cefotaxime, vancomycin and levofloxacin. The resistance rates to erythromycin, clindamycin, azithromycin, tetracycline and chloramphenicol were 17%, 14%, 16%, 98% and 1% respectively. Among the erythromycin resistant isolates, 82.4% had constitutive macrolide-lincosamide-streptogramin B (cMLSB) resistance, 5.9% isolates had inducible MLSB (iMLSB) resistance, and 11.8% isolates had M phenotype resistance. For cMLSB phenotypes, 64.3% harboured ermB gene and 35.7% isolates harboured none of the investigated macrolide resistance genes. The single strain expressing iMLSB phenotype had ermA gene. Of the two strains having M phenotype, only one contained mefA/E gene. Inversely, seven macrolide sensitive strains (MIC range <0.03 μg ml-1) were ermB positive and one macrolide sensitive strain (MIC <0.03 μg ml-1) harboured mefA/E. Tetracycline resistance was predominately due to tetM which was detected alone (83.7%) or associated with tetL (12.2%), tetK (1%), or tetO (1%). One strain carried tetM associated with both tetL and tetK and another strain carried tetO alone. The tetO strains were positive for mefA/E gene and the tetL and tetK carrier strains harboured ermB gene. Susceptible strains harbouring but not expressing an antibiotic resistance gene should be regarded as potentially resistant. These results emphasize the need to monitor epidemiology of antibiotic resistance of GBS in Egypt.
    Journal of Medical Microbiology 07/2014;
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    ABSTRACT: While virulence factors and the biofilm forming capabilities of microbes are the key regulators of wound healing process, the host immune response may also contribute in the events following wound closure or exacerbation of non-closure. We examined samples from diabetic and non-diabetic foot ulcers/wounds for microbial association and tested the microbes for their antibiotic susceptibility and ability to stimulate biofilm formation. A total of 1074 bacterial strains were obtained with staphylococci, Pseudomonas, Citrobacter and enterococci as major colonisers in diabetic samples. Though non-diabetic samples had a similar assemblage, the frequency of occurrence of different groups of bacteria was different. Gram negative bacteria were found to be more prevalent in the diabetic wound environment while, Gram positive bacteria were predominant in non-diabetic ulcers. A higher frequency of monomicrobial infection was observed in samples from non-diabetic individuals when compared to samples from diabetic patients. The prevalence of different groups of bacteria varied when the samples were stratified according to age and sex of the individuals. Several multidrug resistant strains were observed among the samples tested and most of these strains had the ability to elicit moderate to high levels of biofilm. The weakened immune response in diabetic individuals and synergism among pathogenic microorganisms may be critical factors that may determine the delicate balance of wound healing process.
    Journal of Medical Microbiology 07/2014;
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    ABSTRACT: A quantitative real time polymerase chain reaction (qPCR) followed by high resolution melting (HRM) analysis was developed for the differentiation of Mycobacterium species. Rapid differentiation of Mycobacterium species is necessary for the effective diagnosis and management of tuberculosis (TB). In this study, the 16S rRNA gene was tested as the target since this has been identified as a suitable target for the identification of mycobacteria species. During the temperature gradient and primer optimization process, the melting peak (Tm) analysis was determined at the concentration of 50 ng of DNA template and 0.3, 0.4 and 0.5 μM of primer. The qPCR assay for the detection of other mycobacterial species was done at the Tm and primer concentration of 62°C and 0.4 μM, respectively. The HRM analysis generated cluster patterns that were specific and sensitive to distinguished small sequence differences of the Mycobacterium species. This study suggests that the 16S rRNA-based real time PCR followed by HRM analysis produced unique cluster pattern for species of Mycobacterium and could differentiate the closely related mycobacteria species.
    Journal of Medical Microbiology 07/2014;