Prevalence of methicillin resistance and superantigenic toxins in Staphylococcus aureus strains isolated from patients with cancer

Montazeri, Effat Abbasi; Khosravi, Azar Dokht; Khazaei, S; Sabbagh, Ali

doi:10.1186/s12866-021-02319-7

Cited by 12 publications

(5 citation statements)

References 51 publications

(53 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Individuals harbouring MRSA, which is frequently multidrug resistant, are at risk of serious threat to themselves, and also play a role in the dissemination of the pathogen in hospital and community settings. Although the 29/307 MRSA recorded among hospitalised oncology patients examined in Ahvaz, Khuzestan Province, southwest of Iran 22 was much lower, it could not be ruled out that the higher rate observed in this study is unconnected to the antibiotic use pattern in Nigeria. 23 The isolates we examined were mostly from clinical sources and about 24% of the whole collection were from individuals who had no known indications for antibiotic use.…”

Section: Discussioncontrasting

confidence: 59%

Accessory gene regulators and virulence genes associated with the pathogenicity of Staphylococcus aureus from clinical and community settings in Lagos, Nigeria

Enwuru,

Adesida,

Enwuru

et al. 2023

S. Afr. J. Sci.

View full text Add to dashboard Cite

Staphylococcus aureus is a prominent pathogen that causes serious community and hospital-acquired infections globally. Its pathogenicity is attributed to a variety of secreted and cell surface associated proteins that are modulated by the quorum-sensing accessory gene regulator (agr) system. In this study, we investigated the presence of toxin genes and agr involved with S. aureus from clinical samples and apparently healthy individuals. Unequivocal identification of the isolates was obtained with the Vitek 2 system. We screened 70 clinical (CL) and 22 community (C) S. aureus strains for the methicillin resistance (mecA) gene, agr and superantigens (SAg) (enterotoxins and toxic shock syndrome toxin-1) using PCR techniques. A total of 12 clinical isolates were classified as methicillin-resistant S. aureus (MRSA); 89 isolates belonged to one of the four agr groups (agr1-4), and 3 isolates were non-typeable. Of the agr groups, agr1 was the most prominent and mostly consisted of isolates from pus/wounds. The methicillin-susceptible S. aureus (MSSA) isolates were distributed within the four agr groups while MRSA strains were restricted to agr1 and agr3. The most common enterotoxin gene, sei, was likewise more prevalent in MSSA strains than in MRSA strains, where sea predominated. The co-existence of two or more enterotoxins was confirmed in 40% of the isolates. sea occurred through all the agr groups except agr3 and sei was not found in agr1 and agr4. The toxic shock toxin (tst) gene was detected in six MSSA. These findings suggest that MSSA may cause more lethal infections than MRSA because of the increased frequency of toxic genotypes seen in MSSA strains.

show abstract

Section: Discussioncontrasting

confidence: 59%

Accessory gene regulators and virulence genes associated with the pathogenicity of Staphylococcus aureus from clinical and community settings in Lagos, Nigeria

Enwuru,

Adesida,

Enwuru

et al. 2023

S. Afr. J. Sci.

View full text Add to dashboard Cite

show abstract

“…Similarly, some E. coli strains can cause diarrhea and vomiting, and excessive exposure sometimes leads to kidney failure ( Money et al, 2010 ). Specific strains of S. aureus have developed resistance to multiple antibiotics ( Abbasi et al, 2021 ). The XDR S. typhi strain also shows resistance to fluoroquinolone or ceftriaxone, and its outbreak accounts for more than 20,000 cases every year ( Rasheed et al, 2020 ).…”

Section: Introductionmentioning

confidence: 99%

Biosynthesis of phyto-functionalized silver nanoparticles using olive fruit extract and evaluation of their antibacterial and antioxidant properties

et al. 2023

View full text Add to dashboard Cite

The green synthesis of nanomaterials is of utmost interest as it offers an eco-friendly approach over chemical synthetic routes. However, the reported biosynthesis methods are often time-consuming and require heating or mechanical stirring. The current study reports a facile one-pot biosynthesis of silver nanoparticles (AgNPs) mediated by olive fruit extract (OFE) and sunlight irradiation of only 20 s. OFE acts as both a reducing and a capping agent for the formation of OFE-capped AgNPs (AgNPs@OFE). The as-synthesized NPs were systematically characterized by UV-vis spectrometry, Fourier transform infrared (FTIR) spectroscopy, scanning electrochemical microscopy with energy-dispersive X-ray (SEM-EDX), X-ray diffraction (XRD), dynamic light scattering (DLS), and cyclic voltammetry. SEM images confirmed the successful formation of monodispersed spherical AgNPs@OFE of approximately 77 nm. FTIR spectroscopy suggested the involvement of functional groups of phytochemicals from the OFE in the capping and reduction of Ag+ to Ag. The particles revealed excellent colloidal stability as evidenced from the high zeta potential (ZP) value (−40 mV). Interestingly, using the disk diffusion method, AgNPs@OFE revealed higher inhibition efficiency against Gram-negative bacteria (Escherichia coli, Klebsiella oxytoca, and extensively drug-resistant (XDR) Salmonella typhi) than Gram-positive bacteria (Staphylococcus aureus), with Escherichia coli showing the highest inhibition zone of 27 mm. In addition, AgNPs@OFE exhibited maximum potent antioxidant scavenging potential against H2O2, followed by DPPH, O2−, and OH− free radicals. Overall, OFE can be considered an effective source for the sustainable production of stable AgNPs with potential antioxidant and antibacterial activities for biomedical applications.

show abstract

“…It must be emphasized that the Montazeri study was limited to cancer patients, who may have immunological disorders that could affect staphylococcal infection prevalence. 19 This result might also emphasize regional fluctuations in molecular epidemiology. The study from the Middle East showed an even more surprising result: none of the MRSA isolates expressed the eta gene, out of 76 Iraqi isolates and 49 refugee isolates.…”

Section: Discussionmentioning

confidence: 86%

Prevalence of Panton-Valentine leucocidin (pvl) and exfoliative toxin A (eta) gene within methicillin resistant and sensitive Staphylococcus aureus in an urban tertiary referral hospital: A molecular epidemiology pilot study

Amelia,

Kusumawati,

Hasibuan

et al. 2023

F1000Res

View full text Add to dashboard Cite

Background: Staphylococcus aureus is well known to cause a multitude of clinical manifestations, from mild to severe bloodstream infections that could lead to death. Infections are common, either in community-acquired or hospital-acquired settings, and treatment remains a challenge due to methicillin-resistant Staphylococcus aureus (MRSA). The pathogenesis of S. aureus is mediated by several cell-surface and secreted virulence factors. The virulence factors discussed in this study are Panton-Valentine leucocidin (pvl) and exfoliative toxin A (eta). Our pilot study aimed to observe pvl and eta as virulence gene prevalence in a North Sumatera tertiary referral health center. Methods: Our study was a descriptive-analytical observational study with a cross-sectional design in which we collected isolates over a single time period. The frequency of genes is reported as a percentage comparison between MRSA and methicillin-sensitive S. aureus (MSSA). Qualitative gene prevalence analysis was carried out using the polymerase chain reaction (PCR). Results: Our results showed that from 38 MRSA sample isolates, six samples were found to be pvl-negative, or 15.7% of the total samples. From 40 MSSA sample isolates, one sample was found to be pvl-negative MSSA, or 0.025%. Regarding eta, from 38 MRSA sample isolates, 18.4% of the total sample did not have eta, while from 40 MSSA sample isolates, all samples were found to be positive for eta. We found that both pvl and eta were significantly more likely to be expressed in the MSSA strain. Conclusions: Our study shows that pvl and eta are more likely expressed in MSSA strains than in MRSA strains in Indonesia.

show abstract

Prevalence of methicillin resistance and superantigenic toxins in Staphylococcus aureus strains isolated from patients with cancer

Cited by 12 publications

References 51 publications

Accessory gene regulators and virulence genes associated with the pathogenicity of Staphylococcus aureus from clinical and community settings in Lagos, Nigeria

Accessory gene regulators and virulence genes associated with the pathogenicity of Staphylococcus aureus from clinical and community settings in Lagos, Nigeria

Biosynthesis of phyto-functionalized silver nanoparticles using olive fruit extract and evaluation of their antibacterial and antioxidant properties

Prevalence of Panton-Valentine leucocidin (pvl) and exfoliative toxin A (eta) gene within methicillin resistant and sensitive Staphylococcus aureus in an urban tertiary referral hospital: A molecular epidemiology pilot study

Contact Info

Product

Resources

About