Potential Candidates against Staphylococcus aureus and Methicillin-resistant Staphylococcus aureus through the Inhibition of Penicillin-binding Proteins | Chapter 9 | Research Perspectives of Microbiology and Biotechnology Vol. 5

 

The increase of multidrug-resistant bacteria, Staphylococcus aureus (SA) and methicillin-resistant Staphylococcus aureus (MRSA) is an alarming problem for global health in recent years and in the near future. To solve this problem, finding new antibiotics is one of the top priorities. In the structure of MRSA bacteria, penicillin-binding proteins (PBPs) play a role in the integrity of the bacterial cell wall and prevent the entry of harmful molecules into the bacteria. Hence, PBPs are the key factors in the mechanism of antibiotic resistance activity of MRSA. Developing therapies for MRSA-associated infections through compounds that directly act on PBPs is a recent promising approach. To achieve this goal, researchers are going to combine in silico, in vitro, and in vivo experiments to screen and elucidate the mechanism by which natural compounds from herbal plants or compounds in compound libraries such as alkaloids and flavonoids, promising antibiotics agents to inhibit MRSA, target PBPs. This review will introduce the structure properties and pathogen characteristics of SA and MRSA and some promising candidates from herbal medicine and commercial compounds with potential antimicrobial properties against SA and MRSA through interaction with housekeeping genes of PBPs. The information from this study will provide important scientific evidence in the evolution of S. aureus to become MRSA and the potential inhibitors against MRSA, which are innovative approaches to combat antibiotic-resistant Staphylococci in the future.

 

Author(s) Details

Tan Khanh Nguyen
Department of Scientific Management, Dong A University, Danang City- 550000, Vietnam.

Van Ngo Thai Bich
Faculty of Chemical Engineering, The University of Danang-University of Science and Technology, Danang City -550000, Vietnam.

Linh Thuy Thi Tran
Faculty of Pharmacy, Hue University of Medicine and Pharmacy, Hue University, Hue City-530000, Vietnam.

Sa Vo Duong Nguyen
Danang Dermato-Venereology Hospital, Danang City -550000, Vietnam.

Manh Hung Tran
School of Medicine and Pharmacy, The University of Danang, Danang City -550000, Vietnam.

Phu Tran Vinh Pham
VN-UK Institute for Research and Executive Education, The University of Danang, Danang-City 550000, Vietnam.

 

Please see the link:- https://doi.org/10.9734/bpi/rpmab/v5/1353

Physiologically-based Pharmacokinetic Modelling for Optimising Photoactivated Curcumin Dosing in Antimicrobial-Resistant Infections | Chapter 9 | Pharmaceutical Science: New Insights and Developments Vol. 6

 

Background: Photoactivated curcumin primarily exerts its therapeutic effects through the light-induced generation of reactive oxygen species (ROS), resulting in oxidative stress, mitochondrial apoptosis, and modulation of inflammatory pathways. This study aimed to develop whole-body physiologically based pharmacokinetic (PBPK) models to identify appropriate dosing regimens of photoactivated curcumin as an antimicrobial treatment for bacterial-resistant infections.

 

Methods: A whole-body physiologically based pharmacokinetic (PBPK) model was constructed using in vitro and human physiological parameters and validated against a clinical study of curcumin at oral doses of 4000, 6000, and 8000 mg. The verified model was used to simulate novel dosing strategies for photoactivated curcumin formulations. The rate of absorption and water-solubility properties influenced the once-daily and twice-daily oral dosing regimens of photoactivated curcumin. Considering long-acting intramuscular dosing, a weekly dose of 1500 mg with a first-order release rate from the intramuscular depot (Kim) of 0.012 /h and a weekly dose of 1250 mg with the Kim of 0.015 resulted in sufficient exposure. A daily dose of 200 mg with an infusion rate of 100 mg/h, twice-daily doses of 125 mg with an infusion rate of 250 mg/h, and three times-daily doses of 100 mg with an infusion rate of 200 mg/h provided satisfactory pharmacokinetic (PK) profiles.

 

Conclusion: PBPK modelling can be used as a tool to assist in dose optimisation strategies of photoactivated curcumin in various clinical conditions. The weekly intramuscular injection may improve compliance in diseases that require long-term treatment, thereby reducing selective pressure and drug resistance. The intravenous infusion could represent a suitable strategy for critically ill patients in the hospital.

Author(s) Details

Teerachat Sae-heng
Chulabhorn International College of Medicine, Thammasat University, Rangsit Center, 99 Moo 18, Phaholyothin Road, Klongneung Sub-District, Klong Luang District, Pathumthani 12121, Thailand and Center of Excellence in Pharmacology and Molecular Biology of Malaria and Cholangiocarcinoma, Chulabhorn International College of Medicine, Rangsit Center, 99 Moo 18, Phaholyothin Road, Klongneung Subdistrict, Klong Luang District, Pathumthani 12121, Thailand.

 

Juntra Karbwang
Drug Discovery and Development Center, Office of Advanced Science and Technology, Rangsit Center, Thammasat University, 99 Moo 18 Phaholyothin Road, Klongneung Subdistrict, Klong Luang District, Pathumthani, 12121, Thailand.

 

Rajith Kumar Reddi Rajoli
Department of Pharmacology and Therapeutics, Center of Excellence in Long-acting Therapeutics (CELT), University of Liverpool, Liverpool, L69 3BX, United Kingdom.

 

Marco Siccardi
Department of Pharmacology and Therapeutics, Center of Excellence in Long-acting Therapeutics (CELT), University of Liverpool, Liverpool, L69 3BX, United Kingdom.

 

Andrew Owen
Department of Pharmacology and Therapeutics, Center of Excellence in Long-acting Therapeutics (CELT), University of Liverpool, Liverpool, L69 3BX, United Kingdom.

Kesara Na-Bangchang
Chulabhorn International College of Medicine, Thammasat University, Rangsit Center, 99 Moo 18, Phaholyothin Road, Klongneung Sub-District, Klong Luang District, Pathumthani 12121, Thailand, Center of Excellence in Pharmacology and Molecular Biology of Malaria and Cholangiocarcinoma, Chulabhorn International College of Medicine, Rangsit Center, 99 Moo 18, Phaholyothin Road, Klongneung Subdistrict, Klong Luang District, Pathumthani 12121, Thailand and Drug Discovery and Development Center, Office of Advanced Science and Technology, Rangsit Center, Thammasat University, 99 Moo 18 Phaholyothin Road, Klongneung Subdistrict, Klong Luang District, Pathumthani, 12121, Thailand.

 

Please see the book here:- https://doi.org/10.9734/bpi/psnid/v6/5797

Nasal Carriage of Staphylococcus and MRSA with Their Mupirocin Susceptibility among Students in Health-care Settings | Chapter 2 | Research Perspectives of Microbiology and Biotechnology Vol. 8

Objectives: Colonisation of healthcare workers' anterior nares is one of the possible risk factors for nosocomial staphylococcal and Methicillin-resistant Staphylococcus aureus (MRSA) infections. These infections can spread to patients from there and put a strain on the healthcare system. In this regard, an attempt was made to compare the nasal carriage of Staphylococcus and MRSA, as well as their Mupirocin susceptibility, in students who are exposed to the healthcare system and those who are not.

Background: MRSA strains, with their nasal colonization, are well known for their high tendency to spread among the HCWs and from them to the patients, which in turn may lead to an increase in the treatment cost burden by prolonging the duration of hospital stays or the administration of expensive medications and spreading in the community.

Methods: Nasal swabs were collected from 100 paramedical students as the study group and 100 non-medical students as the control group, all in the age group between 18 and 21 years. 5% sheep blood agar and mannitol salt agar were used to isolate S. aureus, and antibiotic sensitivity was done by Kirby Bauer Disc Diffusion Technique. Cefoxitin disc (30 mg) and Vancomycin screen agar were used to detect MRSA and Vancomycin resistance, respectively. A 5 mg disc of Mupirocin was used to test the low-level resistance to Mupirocin and a 200 mg disc was used to test high-level resistance.

Results: The nasal carriage rate of S. aureus and MRSA was 23% and 8% in paramedical students and 17% and 4% in nonmedical students respectively. 83% of isolates from paraclinical students and 95% of isolates from non-medical students were susceptible to linezolid. Out of 12 MRSA strains from both groups, only one strain showed resistance to Mupirocin.

Conclusions: Nasal carriage of S. aureus and MRSA and antibiotic resistance of isolated strains were more common in paramedical students compared to non-medical students. Mupirocin resistance, even in a single case, needs to be addressed. Thus, it is advisable for the infection control team to routinely perform MRSA surveillance and to do nasal decolonization of healthcare workers to prevent the spread of infections among admitted patients.

 

Author (s) Details

 

Bharathi M
Department of Microbiology, Government Medical College, Srikakulam, Andhra Pradesh, India.

 

Sirisha T
Department of Microbiology, Government Medical College, Srikakulam, Andhra Pradesh, India.

 

Please see the book here:- https://doi.org/10.9734/bpi/rpmab/v8/2482