scholarly journals Pseudomonas aeruginosa associated pulmonary infections and in vitro amplification virulent rhamnolipid (rhlR) gene

2022 ◽  
Vol 82 ◽  
Author(s):  
N. M. Ali ◽  
S. Chatta ◽  
I. Liaqat ◽  
S. A. Mazhar ◽  
B. Mazhar ◽  
...  

Abstract Background Pseudomonas aeruginosa is a common opportunistic pathogenic bacterium with the ability to develop a strong communication pathway by quorum sensing system and different virulent factors. Among the various important secretions of P. aeruginosa rhamnolipid is important biological detergent, believed to be involved in the development of the biofilm and intercellular communication. It readily dissolves the lung surfactants that are then easily catalyzed by the phospholipases and in this way is involved in the acute pulmonary infection. Objective research work was designed to investigate virulence and gene associated with virulence in P. aeruginosa responsible for pulmonary infections. Methods In current study polymerase chain reaction (PCR) was used for the detection of the rhlR (rhamnolipid encoding) gene of isolated strains. A number of assays were performed that ensured its virulent behavior. Disc diffusion method was used to check its antibiotic resistance. Isolated strains were resistant to a number of antibiotics applied. Result It was found that males are more prone to respiratory infections as compared to females. Male members with age of 44-58 and 59-73 are at a higher risk, while females with age of 44-58 are also at a risk of pulmonary infections. Antibiotic resistance was observed by measuring zone of inhibition in strains GCU-SG-M4, GCU-SG-M3, GCU-SG-M5, GCU-SG-M2, GCU-SG-M1 and GCU-SG-M6. GCU-SG-M2 was resistant to fluconazole (FLU), clarithromycin (CLR), cefixime (CFM) and Penicillin (P10). No zone of inhibition was observed. But it showed unusual diffused zone around the Ak and MEM antibiotic discs. rhl R gene and 16s rRNA gene were characterized and analyzed. Conclusion Findings from current study would help in raising awareness about antibiotic resistance of P. aeruginosa, and also the sequence of rhl R gene can be used as the diagnostic marker sequence to identify the virulent rhl R gene sequence from the samples when isolated from sputum of Pneumonia patients.

2021 ◽  
Author(s):  
Ewa Jasińska ◽  
Agnieszka Bogut ◽  
Agnieszka Magryś ◽  
Alina Olender

Abstract Purpose: Determination of the association between ica genes and phenotypic biofilm formation in staphylococcal isolates involved in conjunctivitis, their antibiotic resistance as well as detection of selected virulence characteristics: adhesion to epithelial cells and in vitro cytotoxicity.Methods: The study included 26 Staphylococcus aureus (SA) and 26 Staphylococcus epidermidis (SE) isolates. The presence of icaAD genes and ica operon was determined by the PCR assay. Phenotypic biofilm formation was verified using the microtiter plate assay. Antibiotic resistance was performed using the disc diffusion method. Staphylococcal ability to attach to host cells was assessed by flow cytometry. Cytotoxicity on epithelial cells was evaluated by LDH assay.Results: The ica genes were detected in 26.9% of SE and in 42.3% of SA isolates. Only 15.3% of isolates (SE) were positive for both the icaAD and the ica operon. Phenotypically, 19.2% of SE isolates were strong biofilm producers, among which three were both icaAD- and ica operon-positive. 26.9% of SA isolates were strong biofilm producers. Methicillin resistance (MR) was detected in 34.6% of SE and 26.9% of SA isolates. 75% of MR isolates were multidrug resistant. SA isolates adhered to host cells more extensively than SE. SA isolates released higher level of LDH than SE.Conclusions: Adherence abilities were commonly observed in staphylococci associated with conjunctivitis. However, low prevalence of isolates positive for a complete and functional ica locus and low prevalence of strong biofilm producers was detected. SA adhered to a greater extent to eukaryotic cells than SE and were more cytotoxic.


2021 ◽  
Author(s):  
Natalie Lindgren ◽  
Lea Novak ◽  
Benjamin C. Hunt ◽  
Melissa S. McDaniel ◽  
W. Edward Swords

Patients with cystic fibrosis (CF) experience lifelong respiratory infections which are a significant cause of morbidity and mortality. These infections are polymicrobial in nature, and the predominant bacterial species undergo a predictable series of changes as patients age. Young patients have populations dominated by opportunists that are typically found within the microbiome of the human nasopharynx, such as nontypeable Haemophilus influenzae (NTHi); these are eventually supplanted and the population within the CF lung is later dominated by pathogens such as Pseudomonas aeruginosa ( Pa ). In this study, we investigated how initial colonization with NTHi impacts colonization and persistence of Pa in the respiratory tract. Analysis of polymicrobial biofilms in vitro by confocal microscopy revealed that NTHi promoted greater levels of Pa biofilm volume and diffusion. However, sequential respiratory infection of mice with NTHi followed by Pa resulted in significantly lower Pa as compared to infection with Pa alone. Coinfected mice also had reduced airway tissue damage and lower levels of inflammatory cytokines as compared with Pa infected mice. Similar results were observed after instillation of heat-inactivated NTHi bacteria or purified NTHi lipooligosaccharide (LOS) endotoxin prior to Pa introduction. Based on these results, we conclude that NTHi significantly reduces susceptibility to subsequent Pa infection, most likely due to priming of host innate immunity rather than a direct competitive interaction between species. These findings have potential significance with regard to therapeutic management of early life infections in patients with CF.


2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Agata Cieślik-Bielecka ◽  
Tadeusz Bold ◽  
Grzegorz Ziółkowski ◽  
Marcin Pierchała ◽  
Aleksandra Królikowska ◽  
...  

The aim of the study was to investigate the leukocyte- and platelet-rich plasma (L-PRP) antimicrobial activity. The studied sample comprised 20 healthy males. The L-PRP gel, liquid L-PRP, and thrombin samples were testedin vitrofor their antibacterial properties against selected bacterial strains using the Kirby-Bauer disc diffusion method. Two types of thrombin were used (autologous and bovine). Zones of inhibition produced by L-PRP ranged between 6 and 18 mm in diameter. L-PRP inhibited the growth ofStaphylococcus aureus(MRSA and MSSA strains) and was also active againstEnterococcus faecalisandPseudomonas aeruginosa. There was no activity againstEscherichia coliandKlebsiella pneumoniae. The statistically significant increase of L-PRP antimicrobial effect was noted with the use of major volume of thrombin as an activator. Additionally, in groups where a bovine thrombin mixture was added to L-PRP the zones of inhibition concerning MRSA,Enterococcus faecalis, andPseudomonas aeruginosawere larger than in the groups with autologous thrombin. Based on the conducted studies, it can be determined that L-PRP can evokein vitroantimicrobial effects and might be used to treat selected infections in the clinical field. The major volume of thrombin as an activator increases the strength of the L-PRP antimicrobial effect.


2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Shamshul Ansari ◽  
Rabindra Dhital ◽  
Sony Shrestha ◽  
Sangita Thapa ◽  
Ram Puri ◽  
...  

Introduction. Pseudomonas aeruginosais the most frequently isolated organism as it acts as the opportunistic pathogen and can cause infections in immunosuppressed patients. The production of different types of beta-lactamases renders this organism resistant to many commonly used antimicrobials. Therefore, the aim of this study was to document the antibiotic resistance rate inPseudomonas aeruginosaisolated from different clinical specimens.Methods. Pseudomonas aeruginosarecovered was identified by standard microbiological methods. Antibiotic susceptibility testing was performed by modified Kirby-Bauer disc diffusion method following Clinical and Laboratory Standard Institute (CLSI) guidelines and all the suspected isolates were tested for the production of ESBLs, MBLs, and AmpC.Results.Out of total (178) isolates, 83.1% were recovered from the inpatient department (IPD). Majority of the isolates mediated resistance towards the beta-lactam antibiotics, while nearly half of the isolates were resistant to ciprofloxacin. Most of the aminoglycosides used showed resistance rate up to 75% but amikacin proved to be better option. No resistance to polymyxin was observed. ESBLs, MBLs, and AmpC mediated resistance was seen in 33.1%, 30.9%, and 15.7% isolates, respectively.Conclusions. Antibiotic resistance rate and beta-lactamase mediated resistance were high. Thus, regular surveillance of drug resistance is of utmost importance.


2013 ◽  
Vol 14 (5) ◽  
pp. 924-929 ◽  
Author(s):  
Reena Kulshrestha ◽  
J Kranthi ◽  
P Krishna Rao ◽  
Feroz Jenner ◽  
V Abdul Jaleel ◽  
...  

ABSTRACT Aim The present study was conducted to evaluate the efficacy of commercially available herbal toothpastes against the different periodontopathogens. Materials and methods Six herbal toothpastes that were commonly commercially available were included in the study. Colgate herbal, Babool, Meswak, Neem active, Dabur red toothpastes were tested for the study whereas sterile normal saline was used as control. Antimicrobial efficacies of dentifrices were evaluated against Streptococcus mutans and Actinobacillus actinomycetemcomitans. The antimicrobial properties of dentifrices were tested by measuring the maximum zone of inhibition at 24 hours on the Mueller Hinton Agar media inoculated with microbial strain using disk diffusion method. Each dentifrice was tested at 100% concentration (full strength). Results The study showed that all dentifrices selected for the study were effective against the entire test organism but to varying degree. Neem active tooth paste gave a reading of 25.4 mm as the zone of inhibition which was highest amongst all of the test dentifrices. Colgate Herbal and Meswak dentifrices recorded a larger maximum zone of inhibition, measuring 23 and 22.6 mm respectively, compared to other toothpastes. All other dentifrices showed the zone of inhibition to be between 17 and 19 mm respectively. Conclusion The antibacterial properties of six dentifrices were studied in vitro and concluded that almost all of the dentifrices available commercially had antibacterial properties to some extent to benefit dental health or antiplaque action. How to cite this article Jenner F, Jaleel VA, Kulshrestha R, Maheswar G, Rao PK, Kranthi J. Evaluating the Antimicrobial Activity of Commercially Available Herbal Toothpastes on Microorganisms Associated with Diabetes Mellitus. J Contemp Dent Pract 2013;14(5):924-929.


2021 ◽  
Vol 12 ◽  
Author(s):  
Anne-Gaëlle Leroy ◽  
Jocelyne Caillon ◽  
Nathalie Caroff ◽  
Alexis Broquet ◽  
Stéphane Corvec ◽  
...  

Azithromycin (AZM) is a 15-membered-ring macrolide that presents a broad-spectrum antimicrobial activity against Gram-positive bacteria and atypical microorganisms but suffers from a poor diffusion across the outer-membrane of Gram-negative bacilli, including Pseudomonas aeruginosa (PA). However, AZM has demonstrated clinical benefits in patients suffering from chronic PA respiratory infections, especially cystic fibrosis patients. Since the rise of multidrug-resistant PA has led to a growing need for new therapeutic options, this macrolide has been proposed as an adjunctive therapy. Clinical trials assessing AZM in PA acute pneumonia are scarce. However, a careful examination of the available literature provides good rationales for its use in that context. In fact, 14- and 15-membered-ring macrolides have demonstrated immunomodulatory and immunosuppressive effects that could be of major interest in the management of acute illness. Furthermore, growing evidence supports a downregulation of PA virulence dependent on direct interaction with the ribosomes, and based on the modulation of several key regulators from the Quorum Sensing network. First highlighted in vitro, these interesting properties of AZM have subsequently been confirmed in the animal models. In this review, we systematically analyzed the literature regarding AZM immunomodulatory and anti-PA effects. In vitro and in vivo studies, as well as clinical trials were reviewed, looking for rationales for AZM use in PA acute pneumonia.


Author(s):  
M. Binigha ◽  
R. Gayatri Devi ◽  
J. Selavaraj ◽  
A. Jothi Priya

Tecoma stans is a flowering plant belonging to the family Bignoniaceae. It is the floral emblem of the Bahamas. Abutilon indicum belongs to the family Malvaceae. It is also called Indian Mallow. Tecoma stans and Abutilon indicumhave antimicrobial activity and can be used in producing antibiotics. There is an urgent need to produce new antibiotics as there is an increase in the development of pathogen resistant drugs. The aim of this study was to compare the antimicrobial activity of ethanolic extract of Tecoma stansand Abutilonindicum leaves. E.faecalis bacteria were maintained in nutrient agar slopes. The powder of the two herbs, were subjected to extraction by Soxhlet extractor and was concentrated to dry residue by Agar well diffusion method. The nutrient broth was inoculated with bacterial strains. The culture was adjusted to 0.5McFarland turbidity standard. Lawn culture was done in Muller-Hinton agar plate and then the plates were dried. A 6 mm diameter well is bored for different concentrations. The extracts were introduced into the well and allowed to stand for 24 hrs. The antibacterial activity was determined by measuring the zone of inhibition. The present finding on the antimicrobial potential of Abutilon indicum and Tecoma stands showed that the two plants have growth inhibitory activity against oral pathogen E. faecalis. Abutilon indicum has a zone of inhibition greater than Tecoma stans. Abutilon indicum exhibited better activity compared to Tecoma stans.


2021 ◽  
Vol 14 (8) ◽  
Author(s):  
Seyed Ali Bazghandi ◽  
Mohsen Arzanlou ◽  
Hadi Peeridogaheh ◽  
Hamid Vaez ◽  
Amirhossein Sahebkar ◽  
...  

Background: Drug resistance and virulence genes are two key factors for the colonization of Pseudomonas aeruginosa in settings with high antibiotic pressure, such as hospitals, and the development of hospital-acquired infections. Objectives: The objective of this study was to investigate the prevalence of drug resistance and virulence gene profiles in clinical isolates of P. aeruginosa in Ardabil, Iran. Methods: A total of 84 P. aeruginosa isolates were collected from clinical specimens of Ardabil hospitals and confirmed using laboratory standard tests. The disk diffusion method was used for antibiotic susceptibility testing and polymerase chain reaction (PCR) for the identification of P. aeruginosa virulence genes. Results: The highest and the lowest antibiotic resistance rates of P. aeruginosa strains were against ticarcillin-clavulanate (94%) and doripenem (33.3%), respectively. In addition, the frequency of multidrug-resistant (MDR) P. aeruginosa was 55.9%. The prevalence of virulence factor genes was as follows: algD 84.5%, lasB 86.9%, plcH 86.9%, plcN 86.9%, exoU 56%, exoS 51.2%, toxA 81%, nan1 13.1%, and pilB 33.3%. A significant association was observed between resistance to some antibiotics and the prevalence of virulence genes in P. aeruginosa. Conclusions: Our results revealed a high prevalence of antibiotic resistance, especially MDR, and virulence-associated genes in clinical isolates of P. aeruginosa in Ardabil hospitals. Owing to the low resistance rates against doripenem, gentamicin, and tobramycin, these antibiotics are recommended for the treatment of infections caused by highly resistant and virulent P. aeruginosa strains.


2018 ◽  
Vol 4 (3) ◽  
pp. 27-36 ◽  
Author(s):  
Irina Stepanenko ◽  
Semen Yamashkin ◽  
Yuliya Kostina ◽  
Alyona Batarsheva ◽  
Mikhail Mironov

Introduction. The problem of antibiotic resistance of microorganisms is becoming more urgent in the twenty-first century. Microorganisms possess an evolutionary adaptive capacity. Non-adherence to the basic principles of rational antibiotic therapy leads to menacing consequences. More and more pathogenic microbes are becoming resistant to two or more antibiotics. The search for new compounds with antimicrobial activity is one of the principles for overcoming the antibiotic resistance of microorganisms. Materials and methods. Eighteen test-strains of microorganisms and more than 2000 clinical strains of microorganisms, representating the families Micrococcaceae, Streptococcaceae, Enterobacteriaceae, Moraxellaceae, Pseudomonadaceae, Sphingomonadaceae, Xanthomonadaceae were studied for sensitivity to the compounds derived from 4-, 5-, 6- and 7-aminoindoles. A method of serial dilutions to determine the minimal inhibitory concentration (MIC) of the compounds under study was used in the study, as well as a disc diffusion method. Results and discussion. Sensitivity of the test-strains and of clinical strains of microorganisms to the resulting compounds was studied. The compounds based on substituted 4-, 5-, 6-, 7-aminoindoles showed different activity against the test strains and experimental strains of microorganisms in vitro. It was found that the marked antibacterial activity was exhibited by the compounds containing a trifluoromethyl group. The most significant activity was noted in amides and pyrroloquinolones based on 4-aminoindole, 6-aminoindole and 7-aminoindole.The most effective compounds with laboratory codes 5D, 7D, 39D, S3, HD, 4D showed a pronounced antibacterial activity. Conclusion. Antimicrobial activity of the substituted amides and pyrroloquinolines on the basis of 4-, 5-, 6-, 7-aminoindoles was etermined in our study, as well as the spectra of their action against Gram-positive and Gram-negative microorganisms, which are causative agents of non-specific and certain specific human infectious diseases. Moreover, we evaluated the synthetic potentials of the substituted 4-, 5-, 6-, 7-aminoindoles as the starting compounds for synthesizing a series of indolylamides and pyrroloquinolines. Also, the prospects for targeted synthesis of biologically active compounds based on indole-type aromatic amines were determined.


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