Prevalence and epidemiological investigation of mgrB-dependent colistin resistance in extensively drug resistant Klebsiella pneumoniae in Iran.

Carbapenemases-producing K. pneumoniae are challenging antimicrobial therapy of hospitalised patients, which is further complicated by colistin resistance. The aim of this study was to investigate the molecular epidemiological insights into carbapenemases-producing and colistin-resistant clinical K. pneumoniaeA total of 162 colistin resistant clinical strains of K. pneumoniae were collected during 2017-2019. Antimicrobial susceptibility and the colistin minimum inhibitory concentration were determined. Using PCR assay, the prevalence of resistance-associated genes including blaKPC, blaIMP, blaVIM, blaOXA-48, blaNDM-1 and mcr-1 to -9 was examined. Additionally, a PCR assay was used to examine the mgrB gene in colistin-resistant bacteria. 94.4% of the tested strains were resistant to imipenem and 96.3% were resistant to meropenem. Colistin resistance (MIC > 4 µg/L) was observed in 161 isolates (99.4%) by Colistin Broth Disk Elution method. The KPC enzyme was the most common carbapenemase and was identified in 95 strains (58.6%), followed by the IMP, VIM and OXA-48 detected in 47 (29%), 23 (14.2%) and 12 (7.4%) isolates, respectively. However, no NDM-1 gene was detected. Additionally, none of the studied isolates harbored mcr variants, while mgrB gene was observed in 152 (92.6%) isolates. Colistin resistance of K. pneumoniae isolates may be associated with mgrB gene mutation. To stop the spread of resistant K. pneumoniae, surveillance must be improved, infection prevention protocols must be followed, and antibiotic stewardship must be practised.

Antibiotic resistance assessment and multi-drug efflux pumps of Enterococcus faecium isolated from clinical specimens.

INTRODUCTION: Enterococcus faecium is a major cause of community and hospital-acquired infections. Due to limited options for infection with fluoroquinolones-resistant Enterococci, novel therapeutics are urgently needed. Efflux pumps are contributed to fluoroquinolones resistance phenotype in this bacterium and novel inhibitors that target these efflux pumps could be effective in patients. In this research, the possible synergistic effect of an efflux pump inhibitor (EPI), thioridazine, with ciprofloxacin was investigated against clinical isolates of E. faecium. METHODOLOGY: A total of 88 isolates of E. faecium from clinical specimens were studied from August 2017 to September 2018. Conventional phenotypic and molecular methods characterized all the isolates. Standard susceptibility tests and molecular assays determined the antibiotic resistance profiles and the frequency of efflux pump genes. Minimum inhibitory concentrations (MICs) to ciprofloxacin (CIP) in the presence and absence of thioridazine were measured by the micro-broth dilution method. RESULTS: The highest antibiotic resistance rate among E. faecium isolates was related to ciprofloxacin (96.8%), levofloxacin (94.3%), and imipenem (90.9%), respectively. The highest frequency of efflux pump determinants was related to efmA (60, 68%), followed by emeA (48, 54.5%), and efrA and/or efrB genes (45, 51%). The efflux pump inhibitor showed ≥ 2-fold decrease in the MIC value of ciprofloxacin in 48.2% of the isolates. CONCLUSIONS: Efflux pump inhibitor genes efrAB, efmA, and emeA are common among the E. faecium clinical isolates. Our results supported the administration of thioridazine, as an efflux pump inhibitor, in fluoroquinolone-resistant E. faecium infections due to its synergistic effect with CIP.

Mobile genetic elements carrying aminoglycoside resistance genes in Acinetobacter baumannii isolates belonging to global clone 2.

Aminoglycosides are used to treat infections caused by carbapenem-resistant Acinetobacter baumannii (CRAB) strains. However, resistance to aminoglycosides has increased remarkably in the last few years. Here, we aimed to determine the mobile genetic elements (MGEs) associated with resistance to aminoglycosides in the global clone 2 (GC2) A. baumannii. Among the 315 A. baumannii isolates, 97 isolates were identified as GC2, and 52 of GC2 isolates (53.6%) were resistant to all the aminoglycosides tested. The AbGRI3s carrying armA were detected in 88 GC2 isolates (90.7%), and of them, 17 isolates (19.3%) carried a new variant of AbGRI3 (AbGRI3ABI221). aphA6 was located in TnaphA6 of 30 isolates out of 55 aphA6-harboring isolates, and 20 isolates were found to harbor TnaphA6 on a RepAci6 plasmid. Tn6020 carrying aphA1b was detected in 51 isolates (52.5%), which was located within AbGRI2 resistance islands. The pRAY* carrying the aadB gene was detected in 43 isolates (44.3%), and no isolate was found to contain a class 1 integron harboring this gene. The GC2 A. baumannii isolates contained at least one MGE carrying the aminoglycoside resistance gene, located mostly either in the chromosome within AbGRIs or on the plasmids. Thus, it is likely that these MGEs play a role in the dissemination of aminoglycoside resistance genes in GC2 isolates from Iran.

The silent crisis of child abuse in the COVID-19 pandemic: A scoping review.

Background and Aims: The global outbreak of COVID-19 has become an international concern. The lives of children are severely affected by COVID-19 pandemic. There is evidence of a pandemic impact on violence against children. This scoping review study aimed to investigate the effects of the COVID-19 pandemic on child abuse. Methods: We searched PubMed, Scopus, and Web of Science databases to retrieve related studies. Regarding the recent incident of COVID-19, the articles were reviewed from 2019 to June 1, 2021. The terms Child abuse and COVID-19 were used in the precise search technique of each database. The search techniques were created to work with any scientific database that used the keywords given. Results: In the initial search of scientific databases, 568 articles were retrieved. After applying the inclusion and exclusion criteria during the screening process, 16 papers were included in the scoping review. Twelve articles have mentioned the increase of physical, psychological, and neglect types of abuse. However, sexual violence has not been reported in any of the articles. Four articles reported a reduction in the incidence of child abuse. Conclusion: During the COVID-19 pandemic, a crisis occurred in the form of an upsurge in violence toward children, since limits made to diminish the virus, in general, increased the danger to children. Numerous factors such as stress, poverty, financial situation, history of violence, school closures, and lack of contact with support organizations contribute to this phenomenon. Social action and support needed is the right of every child in need in this critical situation.

Global perspective on pediatric growth hormone registries: a systematic review.

BACKGROUND: Registries are considered valuable data sources for identification of pediatric conditions treated with growth hormone (GH), and their follow-up. Currently, there is no systematic literature review on the scope and characteristics of pediatric GH registries. Therefore, the purpose of this systematic review is to identify worldwide registries reported on pediatric GH treatment and to provide a summary of their main characteristics. CONTENT: Pediatric GH registries were identified through a systematic literature review. The search was performed on all related literature published up to January 30th, 2021. Basic information on pediatric GH registries, their type and scope, purpose, sources of data, target conditions, reported outcomes, and important variables were analyzed and presented. SUMMARY: Twenty two articles, reporting on 20 pediatric GH registries, were included in this review. Industrial funding was the most common funding source. The main target conditions included in the pediatric GH registries were: growth hormone deficiency, Turner syndrome, Prader Willi syndrome, small for gestational age, idiopathic short stature, and chronic renal insufficiency. The main objectives in establishing and running pediatric GH registries were assessing the safety and effectiveness of the treatment, describing the epidemiological aspects of target growth conditions and populations, serving public health surveillance, predicting and measuring treatment outcomes, exploring new and useful aspects of GH treatment, and improving the quality of patient care. OUTLOOK: This systematic review provides a global perspective on pediatric GH registries which can be used as a basis for the design and development of new GH registry systems at both national and international levels.

Carriage of CdtB Encoding Campylobacter spp., Salmonella enterica, and Yersinia entercolitica in Patients with Gastroenteritis and Irritable Bowel Syndrome.

INTRODUCTION: Cytolethal distending toxin (Cdt) is one of the bacterial toxins that present in a variety of gram-negative human pathogens, such as E. coli, Salmonella spp., and Campylobacter spp. CDT is composed of three subunits encoded by three adjacent genes, including cdtA, cdtB, and cdtC. cdtB has been shown to have toxic activity and cause DNA damage in host cells. Despite its presence in different bacterial species, the role of CdtB in acute and chronic infections, such as gastroenteritis and irritable bowel syndrome (IBS), is unclear. To analyze this correlation, we studied the prevalence of cdtB among different enteropathogenic bacteria in patients with gastroenteritis and IBS compared with healthy people. MATERIALS AND METHODS: In this cross-sectional descriptive study, 230 stool samples were collected from patients with gastroenteritis, IBS, and healthy people. The presence of CdtB encoding bacteria, including Escherichia coli, Campylobacter spp., Yersinia entercolitica, Providencia alkalifacience, and Salmonella enterica, was examined by polymerase chain reaction using genus-specific primers. RESULTS: Out of 230 stool samples, CdtB encoding Campylobacter spp. were found in 34.6% (52/150), 6.25% (5/80), and 4% (2/50) of the patients with gastroenteritis, IBS, and the control group, respectively. Carriage of CdtB encoding Salmonella enterica was characterized among 5.3% (8/150) of the patients with gastroenteritis and 17.5% (14/80) of the IBS patients. Although none of the patients carried CdtB encoding E. coli and Providencia spp., cdtB of Y. enterocolitica was detected in one of the patients with gastroenteritis (0.6%). Statistical analysis showed significant correlation between infection with CdtB encoding Campylobacter spp. and IBS-D subtype. No significant correlation was found between infection with CdtB encoding bacteria and other clinical and demographic data. CONCLUSION: Our results confirmed a relatively higher frequency of CdtB encoding bacteria in the intestine of patients with gastroenteritis and those with IBS compared with healthy individuals. Regarding the frequency of CdtB encoding Salmonella and Campylobacter bacteria, it was proposed that infection with these enteropathogens could be considered a risk factor for the development or progression of IBS among Iranian patients. Further studies are needed to establish this involvement.

Smart Magnetic Nanocarriers for Multi-Stimuli On-Demand Drug Delivery.

In this study, we report the realization of drug-loaded smart magnetic nanocarriers constituted by superparamagnetic iron oxide nanoparticles encapsulated in a dual pH- and temperature-responsive poly (N-vinylcaprolactam-co-acrylic acid) copolymer to achieve highly controlled drug release and localized magnetic hyperthermia. The magnetic core was constituted by flower-like magnetite nanoparticles with a size of 16.4 nm prepared by the polyol approach, with good saturation magnetization and a high specific absorption rate. The core was encapsulated in poly (N-vinylcaprolactam-co-acrylic acid) obtaining magnetic nanocarriers that revealed reversible hydration/dehydration transition at the acidic condition and/or at temperatures above physiological body temperature, which can be triggered by magnetic hyperthermia. The efficacy of the system was proved by loading doxorubicin with very high encapsulation efficiency (>96.0%) at neutral pH. The double pH- and temperature-responsive nature of the magnetic nanocarriers facilitated a burst, almost complete release of the drug at acidic pH under hyperthermia conditions, while a negligible amount of doxorubicin was released at physiological body temperature at neutral pH, confirming that in addition to pH variation, drug release can be improved by hyperthermia treatment. These results suggest this multi-stimuli-sensitive nanoplatform is a promising candidate for remote-controlled drug release in combination with magnetic hyperthermia for cancer treatment.

Prevalence, species diversity, and antimicrobial susceptibility of Campylobacter strains in patients with diarrhea and poultry meat samples: one-year prospective study.

Background and Objectives: Source tracking of antimicrobial resistance in Campylobacter is useful for control measures. In this study, Campylobacter-associated diarrhea and homology in antimicrobial resistance of humans and poultry meat isolates were investigated. Materials and Methods: A total of 400 stools of patients and 100 poultry meat samples were analyzed. Susceptibility of the isolates was detected by disk diffusion, Etest, and agar dilution methods. Mismatch amplification mutation assay was used for the detection of mutations in the gyrA quinolone resistance determining region (QRDR). Results: Campylobacter spp., including C. jejuni, C. coli, and C. lari, were detected in 35% of the chicken meat and 6.75% of the stool samples, respectively. The QRDR mutation was detected in most of the stool and chicken meat samples. Although the frequency of resistance to tetracycline (53.5% and 62.8%), erythromycin (39.2% and 37.1%), and gentamicin (32.1% and 31.4%) was relatively similar, higher frequency of resistance to ciprofloxacin (51.4% vs 28.6%) and nalidixic acid (42.15% vs 28.6%) among the chicken meat, and ampicillin (50% and 17.1%) among the human stool was detected. Conclusion: High percentage of poultry meat samples is contaminated with different Campylobacter species, which shows homology with the patients' isolates in Tehran.

eHealth solutions to fight against COVID-19: A scoping review of applications.

Background: eHealth has a notable potential to help in prevention, diagnosis, treatment, screening, management, and control of the COVID-19 pandemic. Since ehealth is considered here broadly, as an umbrella term, it also covers subsets like telehealth and mhealth. This study aimed to review the literature to identify and classify subdomains of eHealth solutions that have been utilized, developed, or suggested for the COVID-19 pandemic. Methods: A comprehensive literature search was performed using the PubMed, Scopus, Embase, and Cochrane library databases in April 2020, with no time limitation. The search strategy was built based on 2 concept domains of eHealth solutions and covid-19. For each concept domain, the search query comprised a combination of free text keywords identified from reference papers and controlled vocabulary terms. Obtained results were classified, graphically presented, and discussed. Results: Of the 423 studies identified initially, 35 were included in this study. From related papers, general characteristics, study objective, eHealth-related outcomes, target populations, eHealth interventions, health service category, eHealth solution, and eHealth domain were extracted, classified, and tabulated. Most publication types were ideas, editorials, or opinions (46%). The most targeted populations were people of the community and medical staff (80%). The most implemented or suggested eHealth solution was telehealth (63%), followed by mhealth, health information technology, and health data analytics. Most of the COVID-19 ehealth interventions designed or suggested for improving prevention (48%) and diagnosis (48%). Most of the studies applied or proposed eHealth solutions for general practice or epidemiological purposes (48%). Conclusion: eHealth solutions have the potential to provide useful services to help in COVID-19 pandemics in terms of prevention, diagnosis, treatment, screening, surveillance, resource allocation, education, management, and control. The obtained results from this review might be used for a better understanding of current ehealth solutions provided or recommended in response to the COVID-19 pandemic.

Activity of temocillin and comparators against urinary Escherichia coli and Klebsiella pneumoniae from Iran.

To evaluate the ground susceptibility of urinary Escherichia coli and Klebsiella pneumoniae to temocillin, the susceptibility of temocillin and comparators against 500 clinical isolates (231 E. coli and 269 K. pneumoniae) was tested. Temocillin was either found as the most active antibiotic (susceptibility rate of 92%) or the fourth most active antibiotic (65%), as per its urinary and systemic breakpoint, respectively. No difference of activity was observed in isolates expressing ESBL/AmpC enzymes. Considering the percentage of isolates expressing beta-lactamases and the need to spare broad-spectrum antibiotics, temocillin seems promising for treating urinary tract infections.

Recent advancements in the production of rhamnolipid biosurfactants by Pseudomonas aeruginosa.

Rhamnolipid (RL) biosurfactant which is produced by Pseudomonas species is one of the most effective surface-active agents investigated in the literature. Over the years, many efforts have been made and an array of techniques has been developed for the isolation of RL produced strains as well as RL homolog characterization. Reports show that RL productivity by the best-known producer, Pseudomonas aeruginosa, is very diverse, from less than 1 gr/l to more than 200 g L-1. There are some major parameters that can affect RL productivity. These are culture conditions, medium composition, the mode of operation (batch, fed-batch and continuous), bioengineering/gene manipulation and finally extraction methods. The present paper seeks to provide a comprehensive overview on the production of rhamnolipid biosurfactant by different species of Pseudomonas bacteria. In addition, we have extensively reviewed their potential for possible future applications.

Hybrid Nanogels: Stealth and Biocompatible Structures for Drug Delivery Applications.

Considering nanogels, we have focused our attention on hybrid nanosystems for drug delivery and biomedical purposes. The distinctive strength of these structures is the capability to join the properties of nanosystems with the polymeric structures, where versatility is strongly demanded for biomedical applications. Alongside with the therapeutic effect, a non-secondary requirement of the nanosystem is indeed its biocompatibility. The importance to fulfill this aim is not only driven by the priority to reduce, as much as possible, the inflammatory or the immune response of the organism, but also by the need to improve circulation lifetime, biodistribution, and bioavailability of the carried drugs. In this framework, we have therefore gathered the hybrid nanogels specifically designed to increase their biocompatibility, evade the recognition by the immune system, and overcome the self-defense mechanisms present in the bloodstream of the host organism. The works have been essentially organized according to the hybrid morphologies and to the strategies adopted to fulfill these aims: Nanogels combined with nanoparticles or with liposomes, and involving polyethylene glycol chains or zwitterionic polymers.

Biosurfactants from probiotic bacteria: A review.

Among microorganisms, bacteria are the main group of biosurfactant-producing organisms. Different types of bacteria including Pseudomonas sp., Acinetobacter sp., Bacillus sp., and Arthrobacter sp. are among the most commonly studied bacteria in the realm of scientific research. However, due to the pathogenic nature of the producing organisms, the application of these compounds is restricted, therefore, not suitable for use in food-related industries. Given that probiotic bacteria impact human health, applying probiotics as nonpathogenic and safe organisms have gained much attention for the production of biosurfactants in recent years. Most biosurfactants obtained from probiotic bacteria are related to a number of lactic acid bacteria (LAB). These types of biosurfactants are classified based on their structures as protein-carbohydrate complexes, lipids, or fatty acids. The present paper seeks to provide comprehensive and useful information about the production of various kinds of biosurfactants by different probiotic bacteria. In addition, we have extensively reviewed their potential for possible future applications.

Prevalence of virulence determinants and antibiotic resistance patterns of Enterococcus faecalis strains in patients with community-acquired urinary tract infections in Iran.

The aim of this study was to characterize virulence factors and antibiotic resistance patterns in E. faecalis strains obtained from community-acquired urinary tract infections. A total of 70 E. faecalis isolates from Labbafinejad Hospital in Tehran were collected. Antibiotic resistance and virulence determinants were examined by phenotypic and molecular methods. Among 70 E. faecalis isolates, efba (97.1%), ace (95.7%), and gelE (94.3%) were the most prevalent virulence genes. The most common antibiotic resistance pattern was tetracycline (88.6%) and minocycline (87.1%). Multi-drug resistant phenotype was detected among 10% of them. Our results showed capability of E. faecalis strains for infection of the urinary tract in community. Involvement of virulence determinants in the pathogenesis of community acquired E. faecalis strains was proposed due to their high prevalence rates. Food producing animals were proposed as their environmental reservoirs, due to dominance of tetracycline resistance phenotype among them.

Emergence of blaCTX-M-15, blaTEM-169 and blaPER-1 extended-spectrum ß-lactamase genes among different Salmonella enterica serovars from human faecal samples.

BACKGROUND: Broad-spectrum ß-lactams are used for empirical therapy of severe infections with non-typhoid Salmonella serotypes; however, activities of these drugs against the strains producing different ß-lactamase is not so clear. This study investigated the prevalence of ß-lactamase genes among isolates of S. enterica serovars from human faecal samples and determined their diversity in activity against different ß-lactams. METHODS: Antimicrobial resistance of faecal isolates of S. enterica to extended-spectrum cephalosporins was analysed and MIC values were determined for the strains presenting extended-spectrum ß-lactamases (ESBLs) phenotypes. The ß-lactamase genes were identified by PCR and sequencing. ß-lactamase activity of the Salmonella strains exhibiting ESBL phenotype was detected by biological, iodometric, spectrophotometry and nitrocefin assays. RESULTS: Out of 202 S. enterica isolates, ESBLs phenotype was detected among 3.4% (7/202) of the strains. blaTEM-1 and blaCTX-M-15 were among the frequent ß-lactamase genes. Detection of blaTEM-169 in S. enterica serovar Typhimurium and S. enterica serovar Bredeney and blaPER-1 in S. enterica serovar Infantis was a new finding in this experiment. Location of blaCTX-M-15/blaTEM-169/blaPER-1 genes on plasmid was confirmed in a transformation experiment. While crude extracts of the enzymes from each strain showed higher activity against cephalothin and cefotaxime, the lowest activity was detected against ceftazidime. The greatest synergistic activity was seen in a strain of S. enterica that carried blaCTX-M-15 and blaPER-1 genes compared with those presenting blaCTX-M-15/blaTEM-169 or blaCTX-M-15/blaTEM-1 genotypes. CONCLUSIONS: The results show dissemination of ESBLs encoding genes and their combined activity among different serovars of S. enterica that are a threat for future treatment options.