Open Access Short Research Article

Application of a Novel Tongue Resin Replication System for in vitro Biofilm Studies

Sara Bernardi, Martin Grootveld, Jyoti Tejpal, Katie Laird

Microbiology Research Journal International, Page 1-8
DOI: 10.9734/BMRJ/2016/28606

Aims: Biofilms present a strategy for microorganisms to survive and resist adverse conditions. In order to further our understanding of this resistance mechanism, it is of much importance to develop new methodologies in order to assess such biofilm activities. One of the most defined biofilms is dental plaque. However, the oral cavity contains a different class of biofilm, the precise structural nature of which is dependent on its site of development. Indeed, tongue-coated biofilms have remained a focus for in vitro studies, especially since they represent the major source of oral malodor. The aim of this research was to investigate the growth of a biofilm on a tongue replication constructed from a resin material, and its use in further experimental investigations.

Methods: The model used for this study involved an adapted CDC biofilm reactor in order to achieve this; Staphylococcus aureus was used as the test organism.

Results: Biofilm culturing techniques employed demonstrated a positive growth from the microbes retrieved from the tongue-impressed resin material. Moreover, results acquired confirmed that the resin-based tongue replication harbored significantly greater levels of S. aureus than those of unimpressed resin, plastic and stainless steel controls.

Conclusions: Therefore, this study provides evidence that the employment of a CDC biofilm reactor in combination with a resin tongue device creates an oral biofilm model which provides valuable information regarding our understanding of how the roughness of the dorsal lingual surface affects microbial populations in patients suffering from oral malodor.

Open Access Short Research Article

Rapid Detection of MRSA by Loop Mediated Isothermal Amplification in Bovine Milk Samples

G. Sathish, E. Hemakumar, Kurunchi C. Divya

Microbiology Research Journal International, Page 1-5
DOI: 10.9734/BMRJ/2016/28037

Aim: To develop a simple and rapid detection method for diagnosis of MRSA in bovine milk samples suspected for mastitis.

Methodology: The laboratory sensitivity and specificity of LAMP assay was carried out using available laboratory strains. Milk samples were collected from Thiruvallur and Kanchipuram districts of Tamilnadu, India. DNA was directly isolated from the milk samples and mecA gene was screened by both PCR and LAMP methods.

Results: The LAMP assay successfully amplified the mecA gene under isothermal conditions at 64°C within 60 min. LAMP assay was able to detect 10 pg of DNA and did not amplify mecA gene from bacterial DNA of other species. The screening of milk samples for MRSA showed 47 Positive out of 77 Samples by PCR and 43 positive out of 77 Samples by LAMP.

Conclusion: Application of LAMP assay enabled rapid and easy detection of MRSA in milk samples suspected for bovine mastitis.

Open Access Short Research Article

Hepatitis C Virus Genetic Diversity and Drug Mutational Analysis in Cameroon: 1992 to 2013

Judith Ndongo Torimiro, Laure Arlette Tchapda, Maurice Boda, Jude Saber Bimela, Dale Netski, Désire Takou, Donald Scot Burke, Ubald Tamoufe, Eitel Mpoudi-Ngole, Henry Namme Luma, Oudou Njoya, Wilfred Fon Mbacham, Nathan Wolfe, Stuart Ray

Microbiology Research Journal International, Page 1-10
DOI: 10.9734/BMRJ/2016/28823

HCV infection is endemic in Cameroon. A Direct acting agent (DAAs), sofosbuvir that target the HCV non-structural 5B RNA-dependent RNA polymerase (NS5B RdRp) has recently been incorporated into the standard of care in Cameroon but no drug resistance study to this DAA has been reported in Cameroon. From the laboratory, 157 sequences were obtained and 252 downloaded from the Los Alamos HCV Sequence Database, of which 45 were Core (C), 112 were envelope (E1) and 252 were NS5B sequences were characterized by phylogeny. Drug resistance pattern in the NS5B gene was analyzed using the Geno2Pheno HCV 0.92 tool. Genotypes 1, 2 and 4 were identified. Several drug resistance-associated mutations in the NS5B gene that confer susceptibility (S282T (0.4%), and M414T (0.4%), I434M (2.8%), M414L (6.0%), C289L (13.5%) that confer possible resistance as well as (F415Y (41.3%) and V179A (4.0%) of unknown effect on sofosbuvir (SOF) were identified. There is a low level resistance rate to SOF in Cameroon.

Open Access Original Research Article

Poultry Environment as a Reservoir of Antimicrobial Resistant Bacteria – A Nigerian Story

Tochi Ifeoma Cookey, Kome Otokunefor

Microbiology Research Journal International, Page 1-11
DOI: 10.9734/BMRJ/2016/28601

Aims: This study set out to help define the role of the poultry environment as a reservoir of drug resistant bacteria in Nigeria.

Introduction: The poultry environment has been acclaimed as a potential source of antimicrobial resistant bacteria but information is lacking in Nigeria. Despite worldwide control strategies, a predominance of small-scale poultry farming poses a challenge to proper veterinary monitoring in Nigeria.

Methodology: Three commercial laying farms were sampled and total heterotrophic counts determined. Bacterial identification, susceptibility profile and multiple antibiotic resistance (MAR) index and diversity index were determined using standard methodologies.

Results: Higher bacterial counts were observed in litter than feed samples (6.7 × 107 to 1.6 × 109 CFU/g versus 2.2 × 10to 3.5 × 106 CFU/g) and majority of isolates (73.2%) belonged to only 5 bacterial species (Escherichia coli, Staphylococcus aureus, Enterobacter aerogenes, Klebsiella pneumoniae and Bacillus sp). With respect to antibiotic resistance in general, both litter and faecal matter isolates exhibited similar average rates of 62.2% and 63.1% respectively. Feed samples however had a lower average rate of 46.8%. A similar trend was observed when considering rates of multidrug resistance (MDR). Litter and faecal isolates had MDR rates of 88% and 91% respectively, while feed isolate had a MDR rate of 73%. A focus on the antibiograms of Bacillus cereus, Staphylococcus aureus and Escherichia coli specifically revealed a wide diversity among these isolates with 31 antibiotic resistance patterns observed from 55 isolates and a diversity index of 0.88, 0.9 and 0.98 respectively.

Conclusion: These findings indicate that the Nigerian poultry environment may serve not only as a reservoir of antibiotic resistant organisms, but also as an environment for the development of this resistance. A continuous monitoring of the situation is of essence to form the basis of future intervention strategies.

Open Access Original Research Article

Retro-respective Evaluation of New Fixed Dose Combination of Antibiotics in Management of Severe Skin and Soft Tissue Infections – A Comparative Pharmacoeconomic Study

Prashant Bhatiya, Mohd Amin Mir

Microbiology Research Journal International, Page 1-11
DOI: 10.9734/BMRJ/2016/28477

Study Background: Skin and soft tissue infections (SSTIs) are the second most common infection encountered in hospitals. Present study aims to comparatively analyze efficacy of new fixed dose combination (FDC) with teicoplanin in treating severe SSTI patients and to assess the costs associated with respective therapies.

Materials and Methods: During this retrospective study, case sheets of patients who were treated for severe SSTIs / Sepsis with teicoplanin or fixed dose combination of Vancomycin +Ceftriaxone+ adjuvant (FDC) between March 2009 and August 2012 at tertiary care hospitals were analyzed.  Various demographic features, antibiotic therapy, length of treatment duration and the resulting efficacy were evaluated. Microbiological correlation was done with clinical success monitored in terms of complete omission of systemic signs and symptoms and evaluation of % failure in each case or need of concomitant therapy to treat sepsis.  Overall cost involved in the infections management was estimated in INR.

Results: A total of 314 confirmed SSTI cases out of 538 patients who met other study entrance criteria were further analyzed. Out of these 314 patients, empirical treatment with teicoplanin was received by 186 patients and 128 patients were treated with FDC empirically. Amidst all the patients, 132 (70.96%) of 186 from teicoplanin group and 102 (79.68%) of 128 from FDC group achieved clinical success. 26 / 128 (in FDC group) and 54 /186 (in Teicoplanin group) patients whose MIC falls in intermediate range failed to respond and tigecycline was added to ongoing  therapy. Comparative cost expenditure analysis of the two drug treatment groups revealed that, the overall treatment cost for patients cured with empirical teicoplanin group was 92.83% more than that of FDC therapy. The strongest predictor of the increase in treatment costs was clinical failure. Similar trends were maintained for the patients cured with tigecycline additional therapy, with teicoplanin group accounting 56.63% more expenditure than FDC group.

Conclusion: For the treatment of different types of SSTIs, the empirical intravenous FDC therapy was safe, well tolerated with higher efficacy including in infections caused by multidrug resistant strains (VRSA and GISA) than teicoplanin. Pharmacoeconomic analysis clearly shows that starting appropriate empirical antibiotic therapy has a large impact on the cost of treatment in management of SSTIs and preferring FDC empirically both as mono/combination therapy, can significantly reduce the cost involved in the treatment. Empirical use of FDC followed by correlating it with MIC values can prevent failure and SSTI turning in sepsis.

Open Access Original Research Article

Detection of Heavy Metal Resistance Genes in an Environmental Pseudomonas aeruginosa Isolate

Alaa Mihdir, Abdulrahman S. A. Assaeedi, Hussein H. Abulreesh, Gamal E. H. Osman

Microbiology Research Journal International, Page 1-9
DOI: 10.9734/BMRJ/2016/28655

Aim: To detect heavy metals resistance genes in an environmental Pseudomonas aeruginoas (S 7) isolate.

Place and Duration of Study: Department of Biology, Faculty of Applied Science, Umm Al-Qura University, Makkah, Saudi Arabia, between January and March 2016.

Methodology: Detection of PcoR and CzcD genes involved in metal resistance by PCR. Cloning PCR products and insert the cloned genes into E. coli XL1-Blue. A PCR screening of the two genes was performed on E. coli XL1-Blue to confirm the detection of the two genes and finally amplified cloned PcoR and CzcDgenes were sequenced for further confirmation.

Results: Using primers PcoR and CzcD, two PCR products of 636 bp and 389 bp respectively were detected in P. aeruginosa (S 7). A PCR screening of E. coli XL1-Blue that served as host for the cloned PCR products gave a 636 bp amplification with primer PcoR and a 389 bp amplification with primer CzcD. The inserted genes in E. coli XL-1 Blue were sequenced and confirmed the presence of PcoR and CzcD genes. 

Conclusion: The Pseudomonas aeruginosa (S 7) isolate reported in this study that showed remarkable tolerance to heavy metals by possessing genes involved in two types of efflux systems (P-type ATPase and Cation Diffusion Facilitator), may requires further investigation for its genetic structure and capability to be used in bioremediation of metals-contaminated environments.