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1.
Heliyon ; 10(4): e25934, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38384510

RESUMO

The railway industry has witnessed increasing adoption of digital technologies, known as Railway 4.0, that is revolutionizing operations, infrastructure, and transportation systems. However, developing countries face challenges in keeping pace with these technological advancements. With limited research on Railway 4.0 adoption in developing countries, this study was motivated to investigate the awareness, readiness, and challenges faced by railway professionals towards implementing Railway 4.0 technologies. The aim was to assess the level of awareness and preparedness and identify the key challenges influencing Railway 4.0 adoption in Nigeria's railway construction industry. A questionnaire survey (was distributed to professionals in the railway construction sector to gather their perspectives on awareness of, preparation for, and challenges associated with the use of Railway 4.0 technologies. The results revealed that awareness of Railway 4.0 technologies was moderate, while readiness was low among the professionals. Using exploratory factor analysis, 10 underlying challenge constructs were identified including lack of technical know-how, resistance to change, infrastructure limitations, and uncertainty about benefits, amongst others. Partial Least Square Structural Equation Modelling (PLS-SEM) confirmed these constructs, with reliability and availability, lack of technical know-how, lack of training and resources, and uncertainties in benefit and gains having significant influence on awareness and readiness. The study concludes that focused efforts in training, infrastructure improvement, supportive policies, and communicating the advantages of Railway 4.0 are critical to drive adoption in Nigeria and other developing economies. The findings provide insights into tailoring Railway 4.0 implementation strategies for developing contexts.

2.
J Glob Antimicrob Resist ; 31: 286-291, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36058511

RESUMO

OBJECTIVES: Acinetobacter baumannii is a significant opportunistic pathogen causing nosocomial infections. Infections caused by A. baumannii are often difficult to treat because this bacterium is often multidrug-resistant and shows high environmental adaptability. Here, we report on the analysis of three A. baumannii strains isolated from hospital effluents in South Africa. METHODS: Strains were isolated on Leeds Acinetobacter agar and were identified using VITEK®2 platform. Antibiotic susceptibility testing was performed using the Kirby-Bauer Disk diffusion method. Whole-genome sequencing was performed. The assembled contigs were annotated. Multilocus sequence type, antimicrobial resistance, and virulence genes were identified. RESULTS: The strains showed two multilocus sequence types, ST231 (FA34) and ST1552 (PL448, FG116). Based on their antibiotic susceptibility profiles, PL448 and FG116 were classified as extensively drug-resistant and FA34 as pandrug-resistant. FA34 harbored mutations in LpxA, LpxC, and PmrB, conferring resistance to colistin, but not mcr genes. All three strains encoded virulence genes for immune evasion (capsule, lipopolysaccharide [LPS]), iron uptake, and biofilm formation. FA34 was related to human strains from South Africa; PL448 and FG116 were related to a strain isolated in the United States from a human wound. CONCLUSIONS: The detection of extensively drug- and pandrug-resistant A. baumannii strains in hospital effluents is of particular concern. It indicates that wastewater might play a role in the spread of these bacteria. Our data provide insight into the molecular epidemiology, resistance, pathogenicity, and distribution of A. baumannii in South Africa.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Humanos , Acinetobacter baumannii/genética , Infecções por Acinetobacter/microbiologia , Águas Residuárias , África do Sul , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Hospitais
3.
J Glob Antimicrob Resist ; 29: 150-154, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35257970

RESUMO

OBJECTIVES: The resistome, virulome, mobilome and phylogenetic relationship of the Acinetobacter baumannii isolate FG121 depicting the multilocus sequence type (ST) 231 isolated from hospital effluent water in South Africa was determined using whole-genome sequence analysis. METHOD: A. baumannii FG121 was isolated on Leed Acinetobacter Medium (LAM) agar and the bacterial isolate was identified using the VITEK®2 platform. Antibiotic susceptibility testing was performed using Kirby-Bauer Disk diffusion method. A whole genome sequencing library was constructed from DNA extracted from the isolate using the Illumina Nextera XT library preparation kit and was sequenced using the Illumina NextSeq500 platform. Generated reads were de novo assembled using SpAdes v.3.9. The assembled contigs were annotated, and multilocus sequence type, antimicrobial resistance, and virulence genes were identified. RESULTS: The resistome was consistent with the resistance phenotype of the isolate with resistance determinants for beta-lactams, aminoglycosides, and tetracycline (blaADC-25, blaOXA-23, blaOXA-51, blaNDM-1, aph[3']-VIa and tet[B]). Global phylogenomic analysis using BacWGSTdb revealed that the isolate belonged to the multilocus sequence type ST-231, similar to previously reported isolates from South Africa, the United States, and related to the invasive KR3831 isolate identified from Oman in 2012, suggesting the isolate might be imported from abroad. Virulome analysis predicted both virulence and biofilm-determinants of A. baumannii, which may help to establish infections in adverse conditions. CONCLUSION: This is the first report on a carbapenemase-encoding A. baumannii ST-231 isolated from hospital effluent water. Our data will offer insight into the global phylogenetic, pathogenicity and distribution of A. baumannii in South Africa.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Águas Residuárias , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/genética , Antibacterianos/farmacologia , Proteínas de Bactérias , Farmacorresistência Bacteriana Múltipla/genética , Hospitais , Humanos , Filogenia , África do Sul , Águas Residuárias/microbiologia , beta-Lactamases
4.
J Glob Antimicrob Resist ; 27: 82-90, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34481121

RESUMO

OBJECTIVES: Discharge of drug-resistant, biofilm-forming pathogens from hospital effluent water into municipal wastewater treatment plants poses a public health concern. This study examined the relationship between antibiotic resistance levels and biofilm formation of Acinetobacter baumannii strains isolated from hospital effluents. METHODS: Antibiotic susceptibility of 71 A. baumannii isolates was evaluated by the Kirby-Bauer disk diffusion method. Minimum inhibitory concentrations (MICs) were determined by the agar dilution method, while the minimum biofilm eradication concentration (MBEC) was determined by the broth dilution method. Genotyping was performed for plasmid DNA. Biofilm formation was evaluated by the microtitre plate method and was quantified using crystal violet. A P-value of <0.05 was regarded as statistically significant in all tests. RESULTS: Extensively drug-resistant (XDR) strains made up 58% of the isolates, while multidrug-resistant (MDR) and pandrug-resistant (PDR) strains made up 50% of the isolates from final effluent. The MBEC of ciprofloxacin increased by 255-fold, while that of ceftazidime was as high as 63-1310-fold compared with their respective MICs. Isolates were classified into four plasmid pattern groups with no association between biofilm formation and plasmid type (P = 0.0921). The degree of biofilm formation was independent of the level of antibiotic resistance, although MDR, XDR and PDR isolates produced significant biofilm biomass (P = 0.2580). CONCLUSION: These results suggest that hospital effluent is a potential source of MDR biofilm-forming A. baumannii strains. Appropriate treatment and disposal of effluents are essential to prevent the presence of drug-resistant pathogens in wastewater.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Acinetobacter baumannii/genética , Antibacterianos/farmacologia , Biofilmes , Farmacorresistência Bacteriana Múltipla , Humanos , África do Sul , Centros de Atenção Terciária , Água/farmacologia
5.
Infect Drug Resist ; 12: 3523-3536, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31814741

RESUMO

BACKGROUND: Biofilm formation is an important virulence factor expressed by Acinetobacter baumannii. It shields and protects microbial cells from host immune responses, antibiotics, and other anti-infectives. Its effects on Acinetobacter baumannii infection treatments notwithstanding, important environmental factors that influence its formation have not been fully investigated. METHODS: Biofilm formation was assessed using the qualitative modified Congo red assay and quantitative microtiter plate methods. The combined effect of temperature, medium and shear force was determined by measuring adherence (OD570 nm) in microtiter plate after incubation at 26°C, 30°C, and 37°C when biofilm-grown cells were cultured in the presence of minimal nutrient medium (EAOB) and nutrient-rich medium (TSB) without or with agitation at 50 rpm. Antibiotics susceptibility of meropenem, imipenem, and ciprofloxacin were tested with Kirby-Bauer disc method. P<0.05 was considered statistically significant in all the tests. RESULTS: A noticeable variation in adherence was observed among the isolates cultured with both media. Biofilm forming capacity of the isolates range from 0.09-0.33. The majority of the isolates had their relative biofilm-forming capacity significantly (p<0.05) higher than the positive control, Acinetobacter baumannii ATCC 19606. The biofilm biomass during growth in nutrient-rich medium (TSB) without shaking was significantly different (p<0.05; Tukey's test) among the three temperatures tested compared with when it was cultured in EAOB without shaking. A positive correlation was observed between biofilm formation and resistance to imipenem (r=0.2889; p=0.05). There was a statistically significant difference among the median of the three source groups (p<0.05) compared with the median between the source groups. CONCLUSION: This observation extended further the view that A. baumannii biofilm formation is enhanced when nutrient-poor medium is used at room temperature (26°C) with or without agitation compared to growth at 37°C.

6.
Infect Drug Resist ; 11: 2277-2299, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30532562

RESUMO

Acinetobacter baumannii is a leading cause of nosocomial infections due to its increased antibiotic resistance and virulence. The ability of A. baumannii to form biofilms contributes to its survival in adverse environmental conditions including hospital environments and medical devices. A. baumannii has undoubtedly propelled the interest of biomedical researchers due to its broad range of associated infections especially in hospital intensive care units. The interplay among microbial physicochemistry, alterations in the phenotype and genotypic determinants, and the impact of existing ecological niche and the chemistry of antimicrobial agents has led to enhanced biofilm formation resulting in limited access of drugs to their specific targets. Understanding the triggers to biofilm formation is a step towards limiting and containing biofilm-associated infections and development of biofilm-specific countermeasures. The present review therefore focused on explaining the impact of environmental factors, antimicrobial resistance, gene alteration and regulation, and the prevailing microbial ecology in A. baumannii biofilm formation and gives insights into prospective anti-infective treatments.

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