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Infection and Drug Resistance 2024The World Health Organization (WHO) has classified carbapenem-resistant (), and () as high-priority pathogens, and carbapenem-resistant bacteria (CRB) have been... (Review)
Review
BACKGROUND
The World Health Organization (WHO) has classified carbapenem-resistant (), and () as high-priority pathogens, and carbapenem-resistant bacteria (CRB) have been reported to spread between humans, animals, and the environment.
OBJECTIVE
This study aimed to conduct a systematic review of carbapenem resistance in animals, foods, and the environment on the African continent and to provide recommendations and perspectives for better prevention and control of carbapenem resistance in Africa.
RESULTS
A total of 137 research articles collected from 2009 to 2023 were selected for this review, including articles reporting carbapenem-resistant bacteria in animals (81/137; 59.1%), the environment (66/137; 48.2%), and foods (26/137; 19%). Carbapenem-resistant bacterial species belonged to 31 genera and 17 families, including mainly spp. (68/127; 53.5%); spp. (45/127; 35.4%); spp. (20/127; 15.7%), spp. (19/127; 15%) and spp. (15/127; 11.8%). The prevalence of CRBs by country ranged from 1.1% to 48.5%, and the pooled prevalence of CRBs isolated from animal-environment-food in Africa was 19.1% (2804/14,684; Standard Deviation = 15). Twenty carbapenemase families belonging to A, B, C, and D Ambler classes were reported, including mainly carbapenemase genes from (44/84; 52.4%), (34/84; 40.5%), (23/84; 27.4%), (22/84; 26.2%), (19/84; 22.6%), and (12/84; 14.3%) families. The reported mobile genetic elements (MGE) carrying carbapenemase-encoding genes included plasmids (16/19; 84.2%), integrons (3/19; 15.8%), transposons (3/19; 15.8%), and insertion sequences (2/19; 10.5%). was often carried by (60kb-65kb) IncL/M-type pOXA-48 plasmids, while was often carried by (45-50kb) IncX-type plasmids. Moreover, 25 articles investigated and reported virulent and hypervirulent CRBs that carried multiple virulence factors.
CONCLUSION
Animal-environment-food ecosystems would constitute reservoirs of CRBs involved in human infections. The One Health approach and constant collaboration between governments are necessary to drastically reduce the mortality rates linked to antimicrobial resistance.
PubMed: 38715963
DOI: 10.2147/IDR.S458317 -
Northern Clinics of Istanbul 2023The World Health Organization has designated carbapenem-resistant (CRAB) as a "critical" pathogen on the global priority list of antibiotic-resistant bacteria. This... (Review)
Review
The World Health Organization has designated carbapenem-resistant (CRAB) as a "critical" pathogen on the global priority list of antibiotic-resistant bacteria. This study aims to discuss the molecular epidemiology of CRAB isolates in Turkiye in the last 12 years and the prevalence of gene regions associated with resistance or pathogenesis using a systematic review method. Our study consists of a literature search, determination of eligibility and exclusion criteria, qualitative analysis of studies, data extraction, and statistical analysis. All studies were analyzed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Guidelines. The incidence rates of blaOXA-23, blaOXA-23-like, blaOXA-24/40, blaOXA-24/40-like, blaOXA-51, blaOXA-51-like, blaOXA-58, and blaOXA-58-like genes in CRAB strains were 76.4%, 68.6%, 1.2%, 3.4%, 97.0%, 98.6%, 8.4%, and 17.1%, respectively. It was determined that the prevalence of the blaOXA-23 and blaOXA-58 gene regions showed a statistically significant change over the years. Due to the high prevalence of A. baumannii strains carrying the blaOXA-23 variant, it is necessary to follow its geographical distribution and transposon and plasmid movements. Based on available data, molecular surveillance of CRAB strains should be standardized. In addition, sterilization and disinfection processes applied within the scope of an effective struggle against CRAB strains that can remain live on surfaces for a long time should be reviewed frequently.
PubMed: 37719251
DOI: 10.14744/nci.2022.17003 -
Access Microbiology 2023In Central Africa, it is difficult to tackle antibiotic resistance, because of a lack of data and information on bacterial resistance, due to the low number of studies... (Review)
Review
BACKGROUND
In Central Africa, it is difficult to tackle antibiotic resistance, because of a lack of data and information on bacterial resistance, due to the low number of studies carried out in the field. To fill this gap, we carried out a systematic review of the various studies, and devised a molecular epidemiology of antimicrobial resistance from humans, animals and the environmental samples.
METHOD
A systematic search of all publications from 2005 to 2020 on bacterial resistance in Central Africa (Gabon, Cameroon, Democratic Republic of Congo, Central African Republic, Chad, Republic of Congo, Equatorial Guinea, São Tomé and Príncipe, Angola) was performed on Pubmed, Google scholar and African Journals Online (AJOL). All circulating resistance genes, prevalence and genetic carriers of these resistances were collected. The study area was limited to the nine countries of Central Africa.
RESULTS
A total of 517 studies were identified through a literature search, and 60 studies carried out in eight countries were included. Among all articles included, 43 articles were from humans. Our study revealed not only the circulation of beta-lactamase and carbapenemase genes, but also several other types of resistance genes. To finish, we noticed that some studies reported mobile genetic elements such as integrons, transposons, and plasmids.
CONCLUSION
The scarcity of data poses difficulties in the implementation of effective strategies against antibiotic resistance, which requires a health policy in a 'One Health' approach.
PubMed: 37691840
DOI: 10.1099/acmi.0.000556.v5 -
European Journal of Medical Research Jul 2023Dental pulp stem cells (DPSCs) are adult stem cells with multi-directional differentiation potential derived from ectoderm. Vitro experiments have shown that adding... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Dental pulp stem cells (DPSCs) are adult stem cells with multi-directional differentiation potential derived from ectoderm. Vitro experiments have shown that adding cytokines can help DPSCs to be transformed from multipotent stem cells to osteoblasts. TGF-β has been proved to have an effect on the proliferation and mineralization of bone tissue, but its effect on the osteogenesis and proliferation of dental pulp stem cells is still uncertain. We aim to determine the effect of TGF-β on the osteogenesis and proliferation of dental pulp stem cells.
METHODS
We have identified studies from the Cochrane Central Register of Controlled Trials, PubMed, Embase, and China national knowledge infrastructure (CNKI) for studies interested in TGF-β and proliferation and differentiation of dental pulp stem cells in the following indicators: A490 (an index for evaluating cell proliferation), bone sialoprotein (BSP), Col plasmid-1 (Col-1), osteocalcin (OCN), runt-related transcription factor 2 (Runx-2); and the number of mineralized nodules. Any language restrictions were rejected. Furthermore, we drew a forest plot for each outcome. We conducted a sensitivity analysis, data analysis, heterogeneity, and publication bias test. We evaluate the quality of each study under the guidance of Cochrane's tool for quality assessment.
RESULTS
The pooled data showed that TGF-β could promote the proliferation and ossification of dental pulp stem cells. All the included results support this conclusion except for the number of mineralized nodules: TGF-β increases the A490 index (SMD 3.11, 95% CI [0.54-5.69]), promotes the production of BSP (SMD 3.11, 95% CI [0.81-6.77]), promotes the expression of Col-1 (SMD 4.71, 95% CI [1.25-8.16]) and Runx-2 (SMD 3.37, 95% CI [- 0.63 to 7.36]), increases the content of OCN (SMD 4.32, 95% CI [1.20-7.44]) in dental pulp, and has no significant effect on the number of mineralized nodules (SMD 3.87, 95% CI [- 1.76 to 9.51]) in dental pulp stem cells.
CONCLUSIONS
TGF-β promotes the proliferation and osteogenesis of dental pulp stem cells.
Topics: Humans; Cell Differentiation; Cell Proliferation; Cells, Cultured; Dental Pulp; Osteogenesis; Stem Cells; Transforming Growth Factor beta
PubMed: 37501191
DOI: 10.1186/s40001-023-01227-y -
3 Biotech Jun 2023The present study reviewed and discussed the promising affinity tags for one-step purification and immobilization of recombinant proteins. The approach used to structure... (Review)
Review
A systematic review about affinity tags for one-step purification and immobilization of recombinant proteins: integrated bioprocesses aiming both economic and environmental sustainability.
The present study reviewed and discussed the promising affinity tags for one-step purification and immobilization of recombinant proteins. The approach used to structure this systematic review was The Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) methodology. The Scopus and Web of Science databases were used to perform the bibliographic survey by which 267 articles were selected. After the inclusion/exclusion criteria and the screening process, from 25 chosen documents, we identified 7 types of tags used in the last 10 years, carbohydrate-binding module tag (CBM), polyhistidine (His-tag), elastin-like polypeptides (ELPs), silaffin-3-derived pentalysine cluster (Sil3k tag), N-acetylmuramidase (AcmA tag), modified haloalkane dehalogenase (HaloTag), and aldehyde from a lipase polypeptide (Aldehyde tag). The most used bacterial host for expressing the targeted protein was and the most used expression vector was pET-28a. The results demonstrated two main immobilization and purification methods: the use of supports and the use of self-aggregating tags without the need of support, depending on the tag used. Besides, the chosen terminal for cloning the tag proved to be very important once it could alter enzyme activity. In conclusion, the best tag for protein one-step purification and immobilization was CBM tag, due to the eco-friendly supports that can be provided from industry wastes, the fast immobilization with high specificity, and the reduced cost of the process.
PubMed: 37193330
DOI: 10.1007/s13205-023-03616-w -
Applied and Environmental Microbiology Feb 2023Site-specific recombinases (integrases) can mediate the horizontal transfer of genomic islands. The ability to integrate large DNA sequences into target sites is very...
Site-specific recombinases (integrases) can mediate the horizontal transfer of genomic islands. The ability to integrate large DNA sequences into target sites is very important for genetic engineering in prokaryotic and eukaryotic cells. Here, we characterized an unprecedented catalogue of 530 tyrosine-type integrases by examining genes potentially encoding tyrosine integrases in bacterial genomic islands. The phylogeny of putative tyrosine integrases revealed that these integrases form an evolutionary clade that is distinct from those already known and are affiliated with novel integrase groups. We systematically searched for candidate integrase genes, and their integration activities were validated in a bacterial model. We verified the integration functions of six representative novel integrases by using a two-plasmid integration system consisting of a donor plasmid carrying the integrase gene and site and a recipient plasmid harboring an site in -deficient Escherichia coli. Further quantitative reverse transcription-PCR (qRT-PCR) assays validated that the six selected integrases can be expressed with their native promoters in E. coli. The region reductions showed that the extent of sites of integrases is approximately 200 bp for integration capacity. In addition, mutational analysis showed that the conserved tyrosine at the C terminus is essential for catalysis, confirming that these candidate proteins belong to the tyrosine-type recombinase superfamily, i.e., tyrosine integrases. This study revealed that the novel integrases from bacterial genomic islands have site-specific recombination functions, which is of physiological significance for their genomic islands in bacterial chromosomes. More importantly, our discovery expands the toolbox for genetic engineering, especially for efficient integration activity. Site-specific recombinases or integrases have high specificity for DNA large fragment integration, which is urgently needed for gene editing. However, known integrases are not sufficient for meeting multiple integrations. In this work, we discovered an array of integrases through bioinformatics analysis in bacterial genomes. Phylogeny and functional assays revealed that these new integrases belong to tyrosine-type integrases and have the ability to conduct site-specific recombination. Moreover, region extent and catalysis site analysis were characterized. Our study provides the methodology for discovery of novel integrases and increases the capacity of weapon pool for genetic engineering in bacteria.
Topics: Integrases; Genomic Islands; Escherichia coli; Tyrosine; Plasmids; Bacteriophages; Attachment Sites, Microbiological
PubMed: 36719242
DOI: 10.1128/aem.01738-22 -
Infection and Drug Resistance 2022Carbapenemases are β-lactamase enzymes that hydrolyze a variety of β-lactams including carbapenem and belong to different Ambler classes (A, B, D). These enzymes can... (Review)
Review
Carbapenemases are β-lactamase enzymes that hydrolyze a variety of β-lactams including carbapenem and belong to different Ambler classes (A, B, D). These enzymes can be encoded by plasmid or chromosomal-mediated genes. The major issues associated with carbapenemases-producing organisms are compromising the activity and increasing the resistance to carbapenems which are the last resort antibiotics used in treating serious infections. The global increase of pathogen, carbapenem-resistant has significantly threatened public health. Thus, there is a pressing need for a better understanding of this pathogen, to know the various carbapenem resistance encoding genes and dissemination of resistance genes from which help in developing strategies to overcome this problem. The horizontal transfer of resistant determinants through mobile genetic elements increases the incidence of multidrug, extensive drug, and Pan-drug resistant . Therefore, the current review aims to know the various mechanisms of carbapenem resistance, categorize and discuss carbapenemases encoding genes and various mobile genetic elements, and the prevalence of carbapenemase genes in recent years in from various geographical regions.
PubMed: 36579124
DOI: 10.2147/IDR.S386641 -
Pharmaceutics Dec 2022The exact mechanisms of nucleic acid (NA) delivery with gene electrotransfer (GET) are still unknown, which represents a limitation for its broader use. Further, not... (Review)
Review
The exact mechanisms of nucleic acid (NA) delivery with gene electrotransfer (GET) are still unknown, which represents a limitation for its broader use. Further, not knowing the effects that different experimental electrical and biological parameters have on GET additionally hinders GET optimization, resulting in the majority of research being performed using a trial-and-error approach. To explore the current state of knowledge, we conducted a systematic literature review of GET papers in in vitro conditions and performed meta-analyses of the reported GET efficiency. For now, there is no universal GET strategy that would be appropriate for all experimental aims. Apart from the availability of the required electroporation device and electrodes, the choice of an optimal GET approach depends on parameters such as the electroporation medium; type and origin of cells; and the size, concentration, promoter, and type of the NA to be transfected. Equally important are appropriate controls and the measurement or evaluation of the output pulses to allow a fair and unbiased evaluation of the experimental results. Since many experimental electrical and biological parameters can affect GET, it is important that all used parameters are adequately reported to enable the comparison of results, as well as potentially faster and more efficient experiment planning and optimization.
PubMed: 36559197
DOI: 10.3390/pharmaceutics14122700 -
Tropical Medicine and Infectious Disease Dec 2022The emergence of genetic mutations in chromosomal genes and the transmissible plasmid-mediated colistin resistance gene may have helped in the spread of colistin... (Review)
Review
The emergence of genetic mutations in chromosomal genes and the transmissible plasmid-mediated colistin resistance gene may have helped in the spread of colistin resistance among various Klebsiella pneumoniae (K. pneumoniae) isolates and other different bacteria. In this study, the prevalence of mutated colistin-resistant K. pneumoniae isolates was studied globally using a systematic review and meta-analysis approach. A systematic search was conducted in databases including PubMed, ScienceDirect, Scopus and Google Scholar. The pooled prevalence of mutated colistin resistance in K. pneumoniae isolates was analyzed using Comprehensive Meta-Analysis Software (CMA). A total of 50 articles were included in this study. The pooled prevalence of mutated colistin resistance in K. pneumoniae was estimated at 75.4% (95% CI = 67.2−82.1) at high heterogeneity (I2 = 81.742%, p-value < 0.001). Meanwhile, the results of the subgroup analysis demonstrated the highest prevalence in Saudi Arabia with 97.9% (95% CI = 74.1−99.9%) and Egypt, with 4.5% (95% CI = 0.6−26.1%), had the lowest. The majority of mutations could be observed in the mgrB gene (88%), pmrB gene (54%) and phoQ gene (44%). The current study showed a high prevalence of the mutation of colistin resistance genes in K. pneumoniae. Therefore, it is recommended that regular monitoring be performed to control the spread of colistin resistance.
PubMed: 36548669
DOI: 10.3390/tropicalmed7120414 -
Pathogens (Basel, Switzerland) Jun 2022Antimicrobial resistance is a serious public-health problem throughout the world. , the most common Gram-negative microorganism, has developed different resistance... (Review)
Review
Antimicrobial resistance is a serious public-health problem throughout the world. , the most common Gram-negative microorganism, has developed different resistance mechanisms, making treating infections difficult. Colistin is considered a last-resort drug in the treatment of infections caused by . Plasmid-mediated mobile-colistin-resistant () genes in , now disseminated globally, are considered a major public-health threat. Humans, chickens, and pigs are the main reservoirs for and the sources of antibiotic resistance. Hence, an up-to-date and precise estimate of the global prevalence of resistance genes in these reservoirs is necessary to understand more precisely the worldwide spread and to more effectively implement control and prevention strategies. : Publications were identified in the PubMed database on the basis of the PRISMA guidelines. English full-text articles were selected from December 2014 to March 2021. Descriptive statistics and a meta-analysis were performed in Excel and R software, respectively. Colistin resistance was defined as the molecular-genetic detection of the genes. The crude and estimated prevalence were calculated for each host and continent. The studies were divided into two groups; community-based when they involved isolates from healthy humans, chickens, or pigs, and clinical studies when they involved only hospital, outpatient, or laboratory isolates. : A total of 1278 studies were identified and 218 were included in this systematic review and meta-analysis, divided into community studies (159 studies) and clinical studies (59 studies). The general prevalence of -mediated colistin-resistant () was 6.51% (n = 11,583/177,720), reported in 54 countries and on five continents; Asia with 119 studies followed by Europe with 61 studies registered the most articles. Asia reported the major diversity of -variants (eight of nine, except ). Worldwide, chickens and pigs proved to be the principal reservoir of with an estimated prevalence of 15.8% and 14.9%, respectively. Healthy humans and clinical isolates showed a lower prevalence with 7.4% and 4.2% respectively. : In this systematic review and meta-analysis, the worldwide prevalence of in isolated from healthy humans, chickens, and pigs was investigated. A wide prevalence and distribution of genes was demonstrated on all continents in isolates from the selected reservoirs. Understanding the epidemiology and occurrence in the reservoirs of in on different continents of the world facilitates tracing how genes are transmitted and determining the infection risks for humans. This knowledge can be used to reduce the incidence of zoonotic transmission by implementing the appropriate control programs.
PubMed: 35745513
DOI: 10.3390/pathogens11060659