scholarly journals The effects of U.V light on mrkA, mrkD genes in local isolates of Klebsiella pneumoniae

2017 ◽  
Vol 27 (4) ◽  
Author(s):  
Ali Hussein Alwan ◽  
Sura Mouaid Abass

Klebsiella pneumoniae is dangerous pathogens that can cause severe diseases. This study included isolation of 50 isolates of K.pneumoniaefrom different clinical sources from different hospitals in Baghdad city, the number and percentage of isolates according to the sources (urine, blood, sputum, burns, ear swabs, pus, wounds and stool ) were 22(44%), 11(22%), 4(8%), 4(8%), 3(6%), 3(6%), 2(4%) and 1(2%) respectively. The ability to form biofilm was carried out using Tissue culture plate methods (-TCP-). The results showed that 80% of the isolates were producer biofilm; the genetic study was used to detect the presence of mrkA, mrkD genes that are believed to be responsible of biofilm production. The ratio was mrkA 87.5% and mrkD 50% before exposure to U.V.light to reduce to 43.7% mrkA and 18.7% mrkD in isolates after exposure to U.V.light source. 

Author(s):  
Sarita Manandhar ◽  
Anjana Singh ◽  
Ajit Varma ◽  
Shanti Pandey ◽  
Neeraj Shrivastava

Abstract Background Coagulase-negative staphylococci (CNS) survive as commensals of skin, anterior nares and external canals of human and were regarded as non-infectious pathogens. However, they are emerging as a major cause of nosocomial infectious due to their ability to form biofilms and high resistance to several classes of antibiotics. This study examines the biofilm forming abilities of 214 clinical CNS isolates using phenotypic and genotypic methods, and determines their antibiotic susceptibility patterns. Methods A total of 214 clinical isolates collected from different clinical samples were identified as CNS and their antibiotic susceptibility determined by CLSI guidelines. The biofilm forming ability of all isolates was determined by three phenotypic methods; Congo red agar (CRA) method, tube adherence method (TM) and tissue culture plate (TCP) method and by genotypic method for the detection of icaAD genes. Results Among all the isolates, S. epidermidis (57.5%) was found the most frequently, followed by S. saprophyticus (18.7%), S. haemolyticus (11.2%), S. hominis (7%), and S. capitis (5.6%). Antibiotic susceptibility pattern demonstrated 91.6% isolates were resistant to penicillin and 66.8% to cefoxitin while 91.1% isolates were susceptible to chloramphenicol. Constitutive and inducible clindamycin resistant phenotype as measured by D-test was seen among 28% and 14.5% of isolates respectively. Tissue culture plate method detected biofilm production in 42.1% isolate followed by 31.8% through tube method while 20.1% isolates were found to produce slime in Congo red agar method. The genotypic assay revealed presence of icaA and icaD genes in 19.2% isolates. Conclusion The study shows a high prevalence of biofilm formation and inducible clindamycin resistance in CNS isolates, indicating the importance of in-vitro biofilm production test and D-test in routine laboratory diagnostics. Implementation of efficient diagnostic techniques for detection of biofilm production in clinical samples can help manage staphylococcal infections and minimize risks of treatment failures in hospitals.


Author(s):  
Shadi Shadkam ◽  
Hamid Reza Goli ◽  
Bahman Mirzaei ◽  
Mehrdad Gholami ◽  
Mohammad Ahanjan

Abstract Background Klebsiella pneumoniae is a common cause of nosocomial infections. Antibiotic resistance and ability to form biofilm, as two key virulence factors of K. pneumoniae, are involved in the persistence of infections. The purpose of this study was to investigate the correlation between antimicrobial resistance and biofilm formation capability among K. pneumoniae strains isolated from hospitalized patients in Iran. Methods Over a 10-month period, a total of 100 non-duplicate K. pneumoniae strains were collected. Antibiotic susceptibility was determined by Kirby–Bauer disk diffusion method according to CLSI. Biofilm production was assessed by tissue culture plate method. Finally, polymerase chain reaction was conducted to detect four families of carbapenemase: blaIMP, blaVIM, blaNDM, blaOXA−48; biofilm formation associated genes: treC, wza, luxS; and K. pneumoniae confirming gene: rpoB. Results Most of the isolates were resistant to trimethoprim-sulfamethoxazole (52 %), cefotaxime (51 %), cefepime (43 %), and ceftriaxone (43 %). Among all the 100 isolates, 67 were multidrug-resistant (MDR), and 11 were extensively drug-resistant (XDR). The prevalence of the blaVIM, blaIMP, blaNDM, and blaOXA−48 genes were 7 , 11 , 5 , and 28 %, respectively. The results of biofilm formation in the tissue culture plate assay indicated that 75 (75 %) strains could produce biofilm and only 25 (25 %) isolates were not able to form biofilm. Among these isolates, 25 % formed fully established biofilms, 19 % were categorized as moderately biofilm-producing, 31 % formed weak biofilms, and 25 % were non-biofilm-producers. The antimicrobial resistance among biofilm former strains was found to be significantly higher than that of non-biofilm former strains (p < 0.05). Molecular distribution of biofilm formation genes revealed that 98 , 96 , and 34 % of the isolates carried luxS, treC, and wza genes, respectively. Conclusions The rise of antibiotic resistance among biofilm-producer strains demonstrates a serious concern about limited treatment options in the hospital settings. All of the data suggest that fundamental actions and introduction of novel strategies for controlling of K. pneumoniae biofilm-related infections is essential.


2021 ◽  
Vol 13 (4) ◽  
pp. 1043-1052
Author(s):  
Sarita Manandhar ◽  
Raju Shrestha ◽  
Ratna Shova Tuladhar ◽  
Sunil Lekhak

Resistance to antibiotics, biofilm formation and the presence of virulence factors play important roles in increased mortality associated with infection by staphylococci. The macrolide lincosamide streptogramin B (MLSB) family of antibiotics is commonly used to treat infections by methicillin-resistant isolates. Clinical failure of clindamycin therapy has been reported due to multiple mechanisms that confer resistance to MLSB. This study aims to find the incidence of different phenotypes of MLSB resistance and biofilm production among staphylococci. A total of 375 staphylococci were isolated from different clinical samples, received from two tertiary care hospitals in Nepal. Methicillin resistance was detected by cefoxitin disc diffusion method and inducible clindamycin resistance by D test, according to CLSI guidelines. Biofilm formation was detected by the tissue culture plate method and PCR was used to detect ica genes. Of the total staphylococci isolates, 161 (42.9%) were Staphylococcus aureus, with 131 (81.4%) methicillin-resistant strains, and 214 (57.1%) isolates were coagulase-negative staphylococci, with 143 (66.8%) methicillin-resistant strains. The overall prevalence of constitutive MLSB (cMLSB) and inducible MLSB (iMLSB) phenotypes was 77 (20.5%) and 87 (23.2%), respectively. Both iMLSB and cMLSB phenotypes predominated in methicillin-resistant isolates. The tissue culture plate method detected biofilm formation in 174 (46.4%) isolates and ica genes in 86 (22.9%) isolates. Among biofilm producing isolates, cMLSB and iMLSB phenotypes were 35 (20.1%) and 27 (15.5%), respectively. The cMLSB and iMLSB were 11 (12.8%) and 19 (22.1%), respectively, in isolates possessing ica genes. Clindamycin resistance in the form of cMLSB and iMLSB, especially among MRSA, emphasizes the need for routine D tests to be performed in the lab.


Author(s):  
Prabhjeet S ◽  
Meena A K ◽  
Jesil M

Objective: The objective of the study was to evaluate the efficacy of Ganoderma lucidum toothpaste as an antiplaque agent and to compare its efficacy with herbal toothpaste and mouthwash.Methods: Pooled saliva was collected in a sterile container from the volunteers after taking the consent. Tissue culture plate with 12 (3 × 4) wells was chosen. Pooled saliva of 20 mL was added to each well using the micropipette and was kept in the incubator at 37°C for 72 h. After 72 h, saliva was removed without touching the walls or the base of the wells. Each row was treated either with slurry prepared with Ganoderma/herbal/Colgate total toothpaste or herbal/chlorhexidine mouthwash/distilled water. One row of wells was kept as a control using erythrosine dye. After 30 s, all the wells were rinsed with distilled water. Erythrosine dye was added to all the wells, kept for 30 s, and rinsed with distilled water. The tissue culture plate was kept in the ELx800MS machine (ELISA reader) which was set at 540 nm, and the readings were obtained.Results: The results showed that G. lucidum toothpaste slurry reduced plaque than herbal and chlorhexidine mouthwash. However, there was no significant difference in plaque reduction between herbal and G. lucidum toothpaste slurries.Conclusion: The present study concluded that G. lucidum had better antiplaque efficacy than herbal toothpaste, herbal mouthwash, and chlorhexidine mouthwash.


2020 ◽  
Vol 56 (2) ◽  
pp. 118
Author(s):  
Wira W Lindarto ◽  
Eddy Bagus Wasito ◽  
Kartuti Debora

This study aimed to analyze the effect of glucose induction on the clinical isolate biofilm density of Acinetobacter baumannii. Thirteen clinical isolates of A. baumannii non biofilm forming were collected from non-DM patients who were treated at the ICU of Dr. Soetomo Hospital, Surabaya, was treated with the addition of 0.08% glucose, 0.15% glucose, 0.2% glucose, and 0.4% glucose in TSB growth media, followed by biofilm density examination with Tissue Culture Plate Method (TCPM) using 96 wells flatbottomed polyesterene tissue culture plate and read by autoreader ELISA with a wavelength of 630 nm (OD630). Biofilm density obtained was analyzed using ANOVA statistical analysis. The results of OD630 showed that the biofilm density increased significantly at the addition of 0.2% and 0.4% glucose. There was a significant increase in biofilm density at the addition of 0.2% and 0.4% glucose so that the management of blood sugar levels in ICU patients was needed before and when medical devices were installed.


2018 ◽  
Vol 33 (3) ◽  
pp. 80-85
Author(s):  
Michael O. Osungunna ◽  
Grace O. Onawunmi

Background: Microorganisms that infect humans differ in pathogenesis, virulence factors and antimicrobial resistance profiles. In natural settings, bacterial cells are most often found in close association with surfaces and interfaces, in the form of multicellular aggregates commonly called biofilms. Given their ubiquity and importance in the microbial world, it is hardly surprising that biofilms have attracted the attention of the scientific community. Biofilm formation on medical implant devices such as catheters is also a major problem that is closely tied to the adhesion and resistance-related abilities of the biofilm.Methodology: The ability of 216 bacterial isolates from mid-stream urine (100), catheter-stream urine (52) and catheter tips (64) to form biofilms was investigated using the tissue culture plate method, the tube and Congo red agar methods as well as their antibiotic resistance profiles using the agar disc diffusion method.Results: These revealed that Klebsiella spp. was the predominant bacterial genera accounting for 45.8% of the total isolates. A total of 50 isolates were biofilm-formers with 22% identified by the tissue culture plate method and 78% identified by the Congo red agar method. Klebsiella spp. had the highest ability to form biofilm while antibiotic resistance profiles showed all the biofilmformers to be multiply antibiotic resistant with least resistance to ofloxacin.Conclusion: It can therefore be concluded that some bacterial isolates associated with urinary tract infections have a propensity to form biofilm, thereby becoming multiply antibiotic resistant, and ofloxacin remains the antibiotic of choice in the treatment of such infections.


Author(s):  
Wani Devita Gunardi ◽  
Mohamad Yanuar Prasetyo Nugroho ◽  
Elisabeth D. Harahap

Laporan National Healthcare Safety Network dari tahun 2006 - 2008, menunjukan penyebab paling umum kedua infeksi saluran kemih (ISK) terkait kateter adalah genus Enterococcus setelah Eschericia coli. Pada infeksi saluran kemih terkait kateter urin, faktor yang berperan penting dalam patogenesis infeksi ini, yaitu: pembentukan biofilm pada kateter urin. Peranan Enterococcus faecalis sebagai penyebab infeksi saluran kemih berkaitan dengan kemampuannya dalam membentuk biofilm. Ada beberapa variasi metode untuk mendeteksi pembentukan biofilm seperti Tissue Culture Plate (TCP), Tube method (TM), dan Congo Red Agar (CRA). Tujuan penelitian ini untuk mendapatkan metode deteksi pembentukan biofilm dari E. faecalis yang tepat, cepat, dan mudah dilakukan. Total tigabelas isolat bakteri E. faecalis yang didapat dari hasil isolasi kultur kateter urin dilakukan uji deteksi pembentukan biofilm dengan metode TCP sebagai baku emas dan CRA sebagai pemeriksaan pembanding. Hasilnya, didapatkan 61,5% dan 69,2% bakteri E. faecalis mampu menghasilkan biofilm menggunakan metode TCP dan CRA. Hasil uji diagnostik metode CRA dibandingkan dengan metode TCP untuk deteksi pembentukan biofilm, didapatkan sensitivitas dan spesifisitas dari CRA sebesar 75% dan 40%. CRA merupakan metode yang cepat dan mudah untuk dilakukan, namun memiliki spesifitas yang kurang baik. Hal ini dapat disebabkan pembacaan hasil yang bersifat subjektif dan menimbulkan kesalahan paralaks. Kata kunci : Enterococcus faecalis, Kateter Urin, Biofilm.


2020 ◽  
Vol 21 (8) ◽  
pp. 2688
Author(s):  
Shamsul Sulaiman ◽  
Shiplu Roy Chowdhury ◽  
Mh Busra Fauzi ◽  
Rizal Abdul Rani ◽  
Nor Hamdan Mohamad Yahaya ◽  
...  

Recent advancement in cartilage tissue engineering has explored the potential of 3D culture to mimic the in vivo environment of human cartilaginous tissue. Three-dimensional culture using microspheres was described to play a role in driving the differentiation of mesenchymal stem cells to chondrocyte lineage. However, factors such as mechanical agitation on cell chondrogenesis during culture on the microspheres has yet to be elucidated. In this study, we compared the 2D and 3D culture of bone-marrow-derived mesenchymal stem cells (BMSCs) on gelatin microspheres (GMs) in terms of MSC stemness properties, immune-phenotype, multilineage differentiation properties, and proliferation rate. Then, to study the effect of mechanical agitation on chondrogenic differentiation in 3D culture, we cultured BMSCs on GM (BMSCs-GM) in either static or dynamic bioreactor system with two different mediums, i.e., F12: DMEM (1:1) + 10% FBS (FD) and chondrogenic induction medium (CIM). Our results show that BMSCs attached to the GM surface and remained viable in 3D culture. BMSCs-GM proliferated faster and displayed higher stemness properties than BMSCs on a tissue culture plate (BMSCs-TCP). GMs also enhanced the efficiency of in-vitro chondrogenesis of BMSCs, especially in a dynamic culture with higher cell proliferation, RNA expression, and protein expression compared to that in a static culture. To conclude, our results indicate that the 3D culture of BMSCs on gelatin microsphere was superior to 2D culture on a standard tissue culture plate. Furthermore, culturing BMSCs on GM in dynamic culture conditions enhanced their chondrogenic differentiation.


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