Establishment of rapid diagnostic method for the identification of Staphylococcus aureus in bacterial conjunctivitis

2019 ◽  
Vol 9 (5) ◽  
pp. 484-491 ◽  
Author(s):  
Wei Li ◽  
Aiqin Nie ◽  
Qiang Li ◽  
Ning Xie ◽  
Yunzhi Ling

Staphylococcus aureus is the most frequent cause of conjunctivitis and may lead to severe visual impairment. However, the tools available for the diagnosis, such as bacterial culture and cytology, are often inadequate. Therefore, the goal of the present work was to establish a rapid detection method for S. aureus in the secretions of the conjunctival sac to provide a basis for the early diagnosis of acute bacterial conjunctivitis. The study included 32 patients with acute bacterial conjunctivitis, 30 patients with viral conjunctivitis, and 28 control subjects. Extracted DNA was analyzed by conventional PCR and RT-PCR using primers specific for S. aureus DNA and two antibiotic resistance genes, mecA and femB. By this technique, S. aureus was found in 37.5% of patients with bacterial conjunctivitis, 20% of patients with viral conjunctivitis, and in 7.1% normal control subjects. Except for the control group in which the femB gene was not found, in most other cases S. aureus carried mecA and femB genes. The developed molecular biology approach is faster and more sensitive than the methods requiring bacterial cultures and is uniquely suited for the detection of an S. aureus infection in the eye.

Author(s):  
Fatima N. Aziz ◽  
Laith Abdul Hassan Mohammed-Jawad

Food poisoning due to the bacteria is a big global problem in economically and human's health. This problem refers to an illness which is due to infection or the toxin exists in nature and the food that use. Milk is considered a nutritious food because it contains proteins and vitamins. The aim of this study is to detect and phylogeny characterization of staphylococcal enterotoxin B gene (Seb). A total of 200 milk and cheese samples were screened. One hundred ten isolates of Staphylococcus aureus pre-confirmed using selective and differential media with biochemical tests. Genomic DNA was extracted from the isolates and the SEB gene detects using conventional PCR with specific primers. Three staphylococcus aureus isolates were found to be positive for Seb gene using PCR and confirmed by sequencing. Sequence homology showed variety range of identity starting from (100% to 38%). Phylogenetic tree analyses show that samples (6 and 5) are correlated with S. epidermidis. This study discovered that isolates (A6-RLQ and A5-RLQ) are significantly clustered in a group with non- human pathogen Staphylococcus agnetis.


2021 ◽  
Vol 14 (1) ◽  
pp. 656-664
Author(s):  
I.R. Volchkova ◽  
A.V. Yumashev ◽  
V.V. Borisov ◽  
V.I. Doroshina ◽  
E.A. Kristal ◽  
...  

Introduction: Removable dentures are used by 20% of the population. These may be accompanied by denture stomatitis in 15-70% of patients. The choice of the optimal cleansing agent for removable dental prostheses is of high significance. Aim: The aim of our research was to study the influence of removable denture cleansing products on the adhesion of microorganisms and yeast. Materials and Methods: We manufactured 144 specimens of standardized round shape with a diameter of 10 mm from 4 types of modern polymeric materials used by prosthetic dentistry to produce removable dentures, 12 specimens of each material were placed into suspensions of bacterial cultures of Staphylococcus aureus, Escherichia coli, Candida albicans, then into “ClearaSept” (Test group 1), “Рrotefix active cleanser” (Test group 2), saline solution (Control group), followed by nutrient media. The adhesion index was calculated and analyzed. Results: There was no reliable lowering of adhesion index of Staphylococcus Aureus to all materials detected in Test group 1 (U=6, p>0.05 for Bio XS; U=8, p>0.05 for Dental D, Denotokeep Peek, Vertex Rapid Simplified). In Test group 2, the adhesion index of Staphylococcus Aureus reliably decreased to all materials compared to the Control group (U=0, p≤0.01). The adhesion index of Candida albicans and Escherichia coli to all materials in Test group 1 had a minor to moderate reliable reduction compared to the Control group (U=0, p≤0.01). Test group 2 showed a significant reliable decrease in Candida albicans and Escherichia coli adhesion index to all materials in comparison with the Control group (U=0, p≤0.01). Conclusion: The research showed an unreliable or minor and moderate reliable decrease in microorganisms adhesion index depending on the microorganism species after treatment of denture material specimens by antibacterial soap “ClearaSept” and a reliable significant decrease in microbial and yeast adhesion after application of Protefix active cleaner solution, which demonstrates a more significant antimicrobial effect in comparison to “ClearaSept” against Staphylococcus aureus, Escherichia coli, and Candida albicans.


Author(s):  
Yuwaraj D. Kale ◽  
Sarika Choure

Abhishyanda is one of the Sarvagata Vyadhi mentioned by Acharya Sushruta. In modern science, signs and symptoms of Netrabhishyanda may be correlated with conjunctivitis, which is the inflammatory condition of conjunctiva. Kavala Dharana, Dhumrapana, Aschyotana, Sechana Putapaka etc. are various suggested regimens in Ayurvedic texts for the treatment of Netrabhishyanda. Considering this effectiveness of Palasha as mentioned by Acharya Sushruta, it is planned to study the use of Palasha Mula Arka Aschyotana in Pittaja Netrabhishyanda. 60 patients having classical signs and symptoms of Pittaja Abhishyanda (Acute Bacterial Conjunctivitis) as per Ayurvedic and modern texts were selected for the study. After completion of therapy, mean Conjunctival hyperemia was reduced to 0.2167 ± 0.4086 in Control and 0.5667 ± 0.5040 in Trial Group. Palasha Mula Arka was found effective in reduction in conjunctival hyperemia, watering and the number of culture colonies, it was also found effective in burning sensation, discharge, foreign body sensation and photophobia.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Manal Nabil Hagar ◽  
Farinawati Yazid ◽  
Nur Atmaliya Luchman ◽  
Shahrul Hisham Zainal Ariffin ◽  
Rohaya Megat Abdul Wahab

Abstract Background Mesenchymal stem cells isolated from the dental pulp of primary and permanent teeth can be differentiated into different cell types including osteoblasts. This study was conducted to compare the morphology and osteogenic potential of stem cells from exfoliated deciduous teeth (SHED) and dental pulp stem cells (DPSC) in granular hydroxyapatite scaffold (gHA). Preosteoblast cells (MC3T3-E1) were used as a control group. Methodology The expression of stemness markers for DPSC and SHED was evaluated using reverse transcriptase-polymerase chain reaction (RT-PCR). Alkaline phosphatase assay was used to compare the osteoblastic differentiation of these cells (2D culture). Then, cells were seeded on the scaffold and incubated for 21 days. Morphology assessment using field emission scanning electron microscopy (FESEM) was done while osteogenic differentiation was detected using ALP assay (3D culture). Results The morphology of cells was mononucleated, fibroblast-like shaped cells with extended cytoplasmic projection. In RT-PCR study, DPSC and SHED expressed GAPDH, CD73, CD105, and CD146 while negatively expressed CD11b, CD34 and CD45. FESEM results showed that by day 21, dental stem cells have a round like morphology which is the morphology of osteoblast as compared to day 7. The osteogenic potential using ALP assay was significantly increased (p < 0.01) in SHED as compared to DPSC and MC3T3-E1 in 2D and 3D cultures. Conclusion gHA scaffold is an optimal scaffold as it induced osteogenesis in vitro. Besides, SHED had the highest osteogenic potential making them a preferred candidate for tissue engineering in comparison with DPSC.


Life ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 612
Author(s):  
Eugenia Irene Davidescu ◽  
Irina Odajiu ◽  
Delia Tulbă ◽  
Iulia Mitrea ◽  
Camelia Cucu ◽  
...  

(1) Background: Emerging evidence indicates that non-motor symptoms significantly influence the quality of life in dystonic patients. Therefore, it is essential to evaluate their psychological characteristics and personality traits. (2) Methods: Subjects with idiopathic dystonia and a matched control group were enrolled in this prospective observational cohort study. Inclusion criteria for patient group included idiopathic dystonia diagnosis, evolution exceeding 1 year, and signed informed consent. Inclusion criteria for the control group included lack of neurological comorbidities and signed informed consent. All subjects completed the DECAS Personality Inventory along with an additional form of demographic factors. Data (including descriptive statistics and univariate and multivariate analysis) were analyzed with SPSS. (3) Results: In total, 95 participants were included, of which 57 were in the patient group. Females prevailed (80%), and the mean age was 54.64 ± 12.8 years. The most frequent clinical features of dystonia were focal distribution (71.9%) and progressive disease course (94.73%). The patients underwent regular treatment with botulinum toxin (85.95%). In addition, patients with dystonia obtained significantly higher openness scores than controls, even after adjusting for possible confounders (p = 0.006). Personality traits were also different between the two groups, with patients more often being fantasists (p = 0.007), experimenters (p = 0.022), sophists (p = 0.040), seldom acceptors (p = 0.022), and pragmatics (p = 0.022) than control subjects. (4) Conclusion: Dystonic patients tend to have different personality profiles compared to control subjects, which should be taken into consideration by the treating neurologist.


2021 ◽  
Vol 49 (3) ◽  
pp. 030006052199296
Author(s):  
Juan Wang ◽  
Liu Yang ◽  
Yanjun Diao ◽  
Jiayun Liu ◽  
Jinjie Li ◽  
...  

Objective To evaluate the performance of a DNA methylation-based digital droplet polymerase chain reaction (ddPCR) assay to detect aberrant DNA methylation in cell-free DNA (cfDNA) and to determine its application in the detection of hepatocellular carcinoma (HCC). Methods The present study recruited patients with liver-related diseases and healthy control subjects. Blood samples were used for the extraction of cfDNA, which was then bisulfite converted and the extent of DNA methylation quantified using a ddPCR platform. Results A total of 97 patients with HCC, 80 healthy control subjects and 46 patients with chronic hepatitis B/C virus infection were enrolled in the study. The level of cfDNA in the HCC group was significantly higher than that in the healthy control group. For the detection of HCC, based on a cut-off value of 15.7% for the cfDNA methylation ratio, the sensitivity and specificity were 78.57% and 89.38%, respectively. The diagnostic accuracy was 85.27%, the positive predictive value was 81.91% and the negative predictive value was 87.20%. The positive likelihood ratio of 15.7% in HCC diagnosis was 7.40, while the negative likelihood ratio was 0.24. Conclusions A sensitive methylation-based assay might serve as a liquid biopsy test for diagnosing HCC.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Hamed Nosrati ◽  
Manijeh Hamzepoor ◽  
Maryam Sohrabi ◽  
Massoud Saidijam ◽  
Mohammad Javad Assari ◽  
...  

Abstract Background Silver nanoparticles (AgNPs) can accumulate in various organs after oral exposure. The main objective of the current study is to evaluate the renal toxicity induced by AgNPs after repeated oral exposure and to determine the relevant molecular mechanisms. Methods In this study, 40 male Wistar rats were treated with solutions containing 30, 125, 300, and 700 mg/kg of AgNPs. After 28 days of exposure, histopathological changes were assessed using hematoxylin-eosin (H&E), Masson’s trichrome, and periodic acid-Schiff (PAS) staining. Apoptosis was quantified by TUNEL and immunohistochemistry of caspase-3, and the level of expression of the mRNAs of growth factors was determined using RT-PCR. Results Histopathologic examination revealed degenerative changes in the glomeruli, loss of tubular architecture, loss of brush border, and interrupted tubular basal laminae. These changes were more noticeable in groups treated with 30 and 125 mg/kg. The collagen intensity increased in the group treated with 30 mg/kg in both the cortex and the medulla. Apoptosis was much more evident in middle-dose groups (i.e., 125 and 300 mg/kg). The results of RT-PCR indicated that Bcl-2 and Bax mRNAs upregulated in the treated groups (p < 0.05). Moreover, the data related to EGF, TNF-α, and TGF-β1 revealed that AgNPs induced significant changes in gene expression in the groups treated with 30 and 700 mg/kg compared to the control group. Conclusion Our observations showed that AgNPs played a critical role in in vivo renal toxicity.


2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Xuehan Li ◽  
Tao Huang ◽  
Kai Xu ◽  
Chenglin Li ◽  
Yirong Li

Abstract Background There have been no reports regarding the molecular characteristics, virulence features, and antibiotic resistance profiles of Staphylococcus aureus (S. aureus) from Hainan, the southernmost province of China. Methods Two hundred twenty-seven S. aureus isolates, consisting of 76 methicillin-resistant S. aureus (MRSA) and 151 methicillin-susceptible S. aureus (MSSA), were collected in 2013–2014 and 2018–2019 in Hainan, and investigated for their molecular characteristics, virulence genes, antibiotic resistance profiles and main antibiotic resistance genes. Results Forty sequence types (STs) including three new STs (ST5489, ST5492 and ST5493), and 79 Staphylococcal protein A (spa) types were identified based on multilocus sequence typing (MLST) and spa typing, respectively. ST398 (14.1%, 32/227) was found to be the most prevalent, and the prevalence of ST398-MSSA increased significantly from 2013 to 2014 (5.5%, 5/91) to 2018–2019 (18.4%, 25/136). Seventy-six MRSA isolates were subject to staphylococcus chromosomal cassette mec (SCCmec) typing. SCCmec-IVa was the predominant SCCmec type, and specifically, ST45-SCCmec IVa, an infrequent type in mainland China, was predominant in S. aureus from Hainan. The antibiotic resistance profiles and antibiotic resistance genes of S. aureus show distinctive features in Hainan. The resistant rates of the MRSA isolates to a variety of antibiotics were significantly higher than those of the MSSA isolates. The predominant erythromycin and tetracycline resistance genes were ermC (90.1%, 100/111) and tetK (91.8%, 78/85), respectively. Eleven virulence genes, including the Panton-Valentine leukocidin (pvl) and eta, were determined, and the frequency of eta and pvl were found to be 57.3 and 47.6%. Such high prevalence has never been seen in mainland China before. Conclusion S. aureus isolates in Hainan have unique molecular characteristics, virulence gene and antibiotic resistance profiles, and main antibiotic resistance genes which may be associated with the special geographical location of Hainan and local trends in antibiotic use.


2014 ◽  
Vol 80 (13) ◽  
pp. 3868-3878 ◽  
Author(s):  
Ana Yepes ◽  
Gudrun Koch ◽  
Andrea Waldvogel ◽  
Juan-Carlos Garcia-Betancur ◽  
Daniel Lopez

ABSTRACTProtein localization has been traditionally explored in unicellular organisms, whose ease of genetic manipulation facilitates molecular characterization. The two rod-shaped bacterial modelsEscherichia coliandBacillus subtilishave been prominently used for this purpose and have displaced other bacteria whose challenges for genetic manipulation have complicated any study of cell biology. Among these bacteria is the spherical pathogenic bacteriumStaphylococcus aureus. In this report, we present a new molecular toolbox that facilitates gene deletion in staphylococci in a 1-step recombination process and additional vectors that facilitate the insertion of diverse reporter fusions into newly identified neutral loci of theS. aureuschromosome. Insertion of the reporters does not add any antibiotic resistance genes to the chromosomes of the resultant strains, thereby making them amenable for further genetic manipulations. We used this toolbox to reconstitute the expression ofmreBinS. aureus, a gene that encodes an actin-like cytoskeletal protein which is absent in coccal cells and is presumably lost during the course of speciation. We observed that inS. aureus, MreB is organized in discrete structures in association with the membrane, leading to an unusual redistribution of the cell wall material. The production of MreB also caused cell enlargement, but it did not revert staphylococcal shape. We present interactions of MreB with key staphylococcal cell wall-related proteins. This work facilitates the useS. aureusas a model system in exploring diverse aspects of cellular microbiology.


2015 ◽  
Vol 129 (2) ◽  
pp. 155-158 ◽  
Author(s):  
E Soylu ◽  
I Orhan ◽  
A Cakir ◽  
A Istanbullu ◽  
G Altin ◽  
...  

AbstractObjective:This study compared the results of nasal Staphylococcus aureus carriage and nasal cytology in men with and without a moustache.Methods:The study group comprised 118 adult men with a moustache, and the control group consisted of 123 adult men without a moustache. Samples were taken from the participants' right nasal cavity for cytology and from the left nasal cavity for microbiology.Results:The results for S aureus were positive in 19.5 per cent (n = 23) of participants with a moustache and in 20.3 per cent (n = 25) of men without a moustache. This difference was not significant (p > 0.05). However, nasal cytology revealed rich eosinophil clusters in participants with a moustache.Conclusion:The presence or absence of a moustache had no effect on nasal S aureus colonisation. However, further research is needed to understand whether the presence of a moustache increases the risk of allergic or non-allergic rhinitis.


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