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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 -
Scientific Reports Apr 2022The comprehensive effect size of several commercial vaccines and vaccine candidates against edema disease (ED) has not been evaluated to date. To integrate the... (Meta-Analysis)
Meta-Analysis
The comprehensive effect size of several commercial vaccines and vaccine candidates against edema disease (ED) has not been evaluated to date. To integrate the effectiveness of ED vaccines reported so far and to compare and evaluate the posterior-effect estimates of each vaccine type with network models, we identified eligible studies (n = 12) from the electronic databases using specified search strings. Data for dichotomous outcomes (i.e., mortality and clinical symptoms) and continuous outcomes (i.e., fecal shedding and average daily gain) were extracted and analyzed. Conventional meta-analysis shows that, compared with that in non-vaccinated pigs, vaccinated animals are likely to show reduced mortality (OR = 0.07) and clinical signs of ED (OR = 0.11), and increased productivity (SMD = 0.73). Although reduced fecal shedding (SMD = - 1.29) was observed in vaccinated pigs, this could not be fully determined on insufficient grounds. In contrast to mortality and clinical symptoms, fecal shedding (I = 88%) and average daily gain (I = 85%) showed immense heterogeneity, which was attributed to the small sample size and vaccination route, respectively. According to the Bayesian network meta-analysis, the plasmid-based DNA vaccine demonstrated a better effect for all outcomes compared to other types of vaccines. However, these findings should be carefully interpreted with consideration to potential mediators, insufficient data, and inconsistent network models.
Topics: Animals; Bayes Theorem; Edema; Edema Disease of Swine; Escherichia coli Infections; Network Meta-Analysis; Shiga-Toxigenic Escherichia coli; Swine; Vaccine Efficacy
PubMed: 35440612
DOI: 10.1038/s41598-022-10439-x -
Microorganisms Mar 2022Beta-lactamase (BL) production is a major public health problem. Although not the most frequent AmpC type, AmpC-BL is increasingly isolated, especially plasmid AmpC-BL...
Beta-lactamase (BL) production is a major public health problem. Although not the most frequent AmpC type, AmpC-BL is increasingly isolated, especially plasmid AmpC-BL (pAmpC-BL). The objective of this study was to review information published to date on pAmpC-BL in and and on the epidemiology and detection methods used by clinical microbiology laboratories, by performing a systematic review using the MEDLINE PubMed database. The predictive capacity of a screening method to detect AmpC-BL using disks with cloxacillin (CLX) was also evaluated by studying 102 clinical isolates grown in CHROMID ESBL medium with the addition of cefepime (FEP), cefoxitin (FOX), ertapenem (ETP), CLX, and oxacillin with CLX. The review, which included 149 publications, suggests that certain risk factors (prolonged hospitalization and previous use of cephalosporins) are associated with infections by pAmpC-BL-producing microorganisms. The worldwide prevalence has increased over the past 10 years, with a positivity rate ranging between 0.1 and 40%, although AmpC was only detected when sought in a targeted manner. CMY-2 type has been the most prevalent pAmpC-BL-producing microorganism. The most frequently used phenotypic method has been the double-disk synergy test (using CLX disks or phenyl-boronic acid and cefotaxime [CTX] and ceftazidime) and the disk method combined with these inhibitors. In regard to screening methods, a 1-µg oxacillin disk with CLX showed 88.9% sensitivity, 100% specificity, 100% positive predictive value (PPV), 98.9% negative predictive value (NPV), and 98.9% validity index (VI). This predictive capacity is reduced with the addition of extended-spectrum beta-lactamases, showing 62.5% sensitivity, 100% specificity, 100% PPV, 93.5% NPV, and 94.1% VI. In conclusion, there has been a worldwide increase in the number of isolates with pAmpC-BL, especially in Asia, with CMY-2 being the most frequently detected pAmpC-BL-producing type of microorganism. Reduction in its spread requires routine screening with a combination of phenotypic methods (with AmpC inhibitors) and genotypic methods (multiplex PCR). In conclusion, the proposed screening technique is an easy-to-apply and inexpensive test for the detection of AmpC-producing isolates in the routine screening of multidrug-resistant microorganisms.
PubMed: 35336186
DOI: 10.3390/microorganisms10030611 -
Osong Public Health and Research... Feb 2022Yersinia pestis, the cause of plague and a potential biological weapon, has always been a threatening pathogen. Some strains of Y. pestis have varying degrees of...
Yersinia pestis, the cause of plague and a potential biological weapon, has always been a threatening pathogen. Some strains of Y. pestis have varying degrees of antibiotic resistance. Thus, this systematic review was conducted to alert clinicians to this pathogen's potential antimicrobial resistance. A review of the literature was conducted for experimental reports and systematic reviews on the topics of plague, Y. pestis, and antibiotic resistance. From 1995 to 2021, 7 Y. pestis isolates with 4 antibiotic resistance mechanisms were reported. In Y. pestis 17/95, 16/95, and 2180H, resistance was mediated by transferable plasmids. Each plasmid contained resistance genes encoded within specific transposons. Strain 17/95 presented multiple drug resistance, since plasmid 1202 contained 10 resistance determinants. Strains 16/95 and 2180H showed single antibiotic resistance because both additional plasmids in these strains carried only 1 antimicrobial determinant. Strains 12/87, S19960127, 56/13, and 59/13 exhibited streptomycin resistance due to an rpsl gene mutation, a novel mechanism that was discovered recently. Y. pestis can acquire antibiotic resistance in nature not only via conjugative transfer of antimicrobial-resistant plasmids from other bacteria, but also by gene point mutations. Global surveillance should be strengthened to identify antibiotic-resistant Y. pestis strains by whole-genome sequencing and drug susceptibility testing.
PubMed: 35255676
DOI: 10.24171/j.phrp.2021.0288 -
Antibiotics (Basel, Switzerland) Feb 2022Antimicrobial resistance to treatments for infection (CDI) poses a significant threat to global health. is widely thought to be susceptible to oral vancomycin, which... (Review)
Review
Antimicrobial resistance to treatments for infection (CDI) poses a significant threat to global health. is widely thought to be susceptible to oral vancomycin, which is increasingly the mainstay of CDI treatment. However, clinical labs do not conduct susceptibility testing, presenting a challenge to detecting the emergence and impact of resistance. In this systematic review, we describe gene determinants and associated clinical and laboratory mechanisms of vancomycin resistance in , including drug-binding site alterations, efflux pumps, RNA polymerase mutations, and biofilm formation. Additional research is needed to further characterize these mechanisms and understand their clinical impact.
PubMed: 35203860
DOI: 10.3390/antibiotics11020258 -
Environmental Microbiology Mar 2022Gram-negative bacteria (GNB) continue to develop resistance against important antibiotics including last-resort ones such as carbapenems and polymyxins. An analysis of... (Meta-Analysis)
Meta-Analysis
Gram-negative bacteria (GNB) continue to develop resistance against important antibiotics including last-resort ones such as carbapenems and polymyxins. An analysis of GNB with co-resistance to carbapenems and polymyxins from a One Health perspective is presented. Data of species name, country, source of isolation, resistance genes (ARGs), plasmid type, clones and mobile genetic elements (MGEs) were deduced from 129 articles from January 2016 to March 2021. Available genomes and plasmids were obtained from PATRIC and NCBI. Resistomes and methylomes were analysed using BAcWGSTdb and REBASE whilst Kaptive was used to predict capsule typing. Plasmids and other MEGs were identified using MGE Finder and ResFinder. Phylogenetic analyses were done using RAxML and annotated with MEGA 7. A total of 877 isolates, 32 genomes and 44 plasmid sequences were analysed. Most of these isolates were reported in Asian countries and were isolated from clinical, animal and environmental sources. Colistin resistance was mostly mediated by mgrB inactivation (37%; n = 322) and mcr-1 (36%; n = 312), while OXA-48/181 was the most reported carbapenemase. IncX and IncI were the most common plasmids hosting carbapenemases and mcr genes. The isolates were co-resistant to other antibiotics, with floR (chloramphenicol) and fosA3 (fosfomycin) being common; E. coli ST156 and K. pneumoniae ST258 strains were common globally. Virulence genes and capsular KL-types were also detected. Type I, II, III and IV restriction modification systems were detected, comprising various MTases and restriction enzymes. The escalation of highly resistant isolates drains the economy due to untreatable bacterial infections, which leads to increasing global mortality rates and healthcare costs.
Topics: Animals; Anti-Bacterial Agents; Carbapenems; Drug Resistance, Bacterial; Epigenomics; Escherichia coli; Escherichia coli Proteins; Gram-Negative Bacteria; Klebsiella pneumoniae; Microbial Sensitivity Tests; One Health; Phylogeny; Plasmids; Polymyxins; beta-Lactamases
PubMed: 35129271
DOI: 10.1111/1462-2920.15930 -
Antimicrobial Resistance and Infection... Jan 2022Antimicrobial resistance is swiftly increasing all over the world. In Africa, it manifests more in pathogenic bacteria in form of antibiotic resistance (ABR). On this... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Antimicrobial resistance is swiftly increasing all over the world. In Africa, it manifests more in pathogenic bacteria in form of antibiotic resistance (ABR). On this continent, bacterial contamination of commonly used herbal medicine (HM) is on the increase, but information about antimicrobial resistance in these contaminants is limited due to fragmented studies. Here, we analyzed research that characterized ABR in pathogenic bacteria isolated from HM in Africa since 2000; to generate a comprehensive understanding of the drug-resistant bacterial contamination burden in this region.
METHODS
The study was conducted according to standards of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). We searched for articles from 12 databases. These were: PubMed, Science Direct, Scifinder scholar, Google scholar, HerbMed, Medline, EMBASE, Cochrane Library, International Pharmaceutical Abstracts, Commonwealth Agricultural Bureau Abstracts, African Journal Online, and Biological Abstracts. Prevalence and ABR traits of bacterial isolates, Cochran's Q test, and the I statistic for heterogeneity were evaluated using MedCalcs software. A random-effects model was used to determine the pooled prevalence of ABR traits. The potential sources of heterogeneity were examined through sensitivity analysis, subgroup analysis, and meta-regression at a 95% level of significance.
FINDINGS
Eighteen studies met our inclusion criteria. The pooled prevalence of bacterial resistance to at least one conventional drug was 86.51% (95% CI = 61.247-99.357%). The studies were highly heterogeneous (I = 99.17%; p < 0.0001), with no evidence of publication bias. The most prevalent multidrug-resistant species was Escherichia coli (24.0%). The most highly resisted drug was Ceftazidime with a pooled prevalence of 95.10% (95% CI = 78.51-99.87%), while the drug-class was 3 generation cephalosporins; 91.64% (95% CI = 78.64-96.73%). None of the eligible studies tested isolates for Carbapenem resistance. Extended Spectrum β-lactamase genes were detected in 89 (37.2%) isolates, mostly Salmonella spp., Proteus vulgaris, and K. pneumonia. Resistance plasmids were found in 6 (5.8%) isolates; the heaviest plasmid weighed 23,130 Kilobases, and Proteus vulgaris harbored the majority (n = 5; 83.3%).
CONCLUSIONS
Herbal medicines in Africa harbor bacterial contaminants which are highly resistant to conventional medicines. This points to a potential treatment failure when these contaminants are involved in diseases causation. More research on this subject is recommended, to fill the evidence gaps and support the formation of collaborative quality control mechanisms for the herbal medicine industry in Africa.
Topics: Africa; Anti-Bacterial Agents; Bacteria; Drug Contamination; Drug Resistance, Bacterial; Food Contamination; Herbal Medicine
PubMed: 35063036
DOI: 10.1186/s13756-022-01054-6 -
Virology Journal Dec 2021Vaccination against HCV is an effective measure in reduction of virus-related public health burden and mortality. However, no prophylactic vaccine is available as of...
BACKGROUND
Vaccination against HCV is an effective measure in reduction of virus-related public health burden and mortality. However, no prophylactic vaccine is available as of yet. DNA-based immunization is a promising modality to generate cellular and humoral immune responses. The objective of this study is to provide a systematic review of HCV DNA vaccines and investigate and discuss the strategies employed to optimize their efficacies.
METHODS
MEDLINE (PubMed), Web of Science, Scopus, ScienceDirect, and databases in persian language including the Regional Information Centre for Science & Technology (RICeST), the Scientific Information Database and the Iranian Research Institute for Information Science and Technology (IranDoc) were examined to identify studies pertaining to HCV nucleic acid vaccine development from 2000 to 2020.
RESULTS
Twenty-seven articles were included. Studies related to HCV RNA vaccines were yet to be published. A variety of strategies were identified with the potential to optimize HCV DNA vaccines such as incorporating multiple viral proteins and molecular tags such as HBsAg and Immunoglobulin Fc, multi-epitope expression, co-expression plasmid utilization, recombinant subunit immunogens, heterologous prime-boosting, incorporating NS3 mutants in DNA vaccines, utilization of adjuvants, employment of less explored methods such as Gene Electro Transfer, construction of multi- CTL epitopes, utilizing co/post translational modifications and polycistronic genes, among others. The effectiveness of the aforementioned strategies in boosting immune response and improving vaccine potency was assessed.
CONCLUSIONS
The recent progress on HCV vaccine development was examined in this systematic review to identify candidates with most promising prophylactic and therapeutic potential.
Topics: Animals; Hepacivirus; Hepatitis C; Humans; Iran; Mice; Mice, Inbred BALB C; Vaccines, DNA; Viral Hepatitis Vaccines
PubMed: 34903252
DOI: 10.1186/s12985-021-01716-8