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Small-sized nanoparticles are widely used in applications such as catalysis, nanoelectronics, and hydrogen storage. However, the small size causes a common problem: agglomeration on the support template. One solution is to use templates that limit the mobility of the nanoparticles. Graphene nanomeshes (GNMs) are two dimensional porous structures with controllably passivated pores. In this work, we employ first principles calculations to investigate the potential for using GNMs as support templates for Ni clusters and, at the same time, study their magnetic and hydrogen storage properties. We consider two Ni clusters (Ni6 and Ni13) and two GNMs (O-terminated and N-terminated), comparing our results to those of isolated Ni clusters and those of Ni clusters on graphene. High stability of the Ni clusters is found on the N-GNM in contrast to the O-GNM. We quantify the hydrogen storage capacity by calculating the adsorption energy for multiple H2 molecules. The values on Nix/N-GNM are significantly reduced as compared to the corresponding isolated Nix clusters, but a high hydrogen storage capacity is maintained. The fact that Nix/N-GNM hosts spin polarization is interesting for spintronic applications. [ABSTRACT FROM AUTHOR]

The magnetic and transport properties of the metal phthalocyanine (MPc) and F16MPc (M = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn and Ag) families of molecules in contact with S–Au wires are investigated by density functional theory within the local density approximation, including local electronic correlations on the central metal atom. The magnetic moments are found to be considerably modified under fluorination. In addition, they do not depend exclusively on the configuration of the outer electronic shell of the central metal atom (as in isolated MPc and F16MPc) but also on the interaction with the leads. Good agreement between the calculated conductance and experimental results is obtained. For M = Ag, a high spin filter efficiency and conductance is observed, giving rise to a potentially high sensitivity for chemical sensor applications. [ABSTRACT FROM AUTHOR]

Background: Antimicrobial resistance is an emerging problem worldwide, endangering antimicrobials efficacy and resulting in high rates of morbidity and mortality. It is one of the major concerns that health care facilities are facing nowadays. Mainly, extended-spectrum beta-lactamases (ESBL)-producing Enterobacterales play a role in hydrolyzing β-lactams, specifically the third-generation cephalosporins. This study aimed to investigate the prevalence of fecal carriage and molecular characterization of ESBL-producing Enterobacterales among Lebanese elderly residents in a long-term care facility (Dar Al-Ajaza Al Islamia Hospital)., Methods: Rectal culture swab specimens were collected from 132 patients at Dar Al Ajaza Al Islamia hospital between January 2019 till June 2020. The phenotype of ESBL producers was confirmed by a modified double disc synergy test and antibiotic susceptibility was determined using the Kirby-Bauer disk diffusion method. Genotypically, multiplex polymerase chain reaction was used to detect the ESBL genes., Results: The main Enterobacterales strain observed was E coli (90.15%) followed by Klebsiella pneumoniae (4.54%) and Klebsiella oxytoca (3.80%). It has been found that the ESBL percentage rate has decreased when compared to a study conducted previously at the same hospital. Moreover, the predominant ESBL gene was CTX-M (cefotaximase)., Conclusions: This study is the first to demonstrate the improved current status of ESBL in one long-term care facility. In addition, the CTX-M is still the major type in ESBL-producing organisms., (Copyright © 2023 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.)

Introduction: Antimicrobial resistance (AMR) is a worldwide problem that threatens treatment effectiveness against the most serious bacterial infections. AMR in Enterobacterales is highly prevalent in Lebanon. However, recent reports regarding the distribution of Enterobacterales and related antimicrobial susceptibility are scarce., Methodology: In this retrospective study at the Lebanese Hospital Geitaoui Medical Center in Lebanon, all data regarding culture specimens from urine, blood, sputum, deep tracheal aspirate, broncho-alveolar lavage, wounds, surgical sites, tissue, body fluids, and central venous catheter that were positive for at least one of the 4 bacterial isolates (Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae and Proteus mirabilis) were collected. All susceptibility testing was performed according to the Clinical and Laboratory Standards Institute guidelines., Results: A total of 4283 non-duplicate Enterobacterales were isolated during the study period (January 2017 to December 2020). Urine was the most common site of infection. E. coli was the most detected isolate as well as the leading pathogen in urine, wounds and surgical sites, and blood. Regarding antimicrobial susceptibility, the mean susceptibility to third generation cephalosporins was 55.53% and a mean extended-spectrum β-lactamases production of 31.2% was measured in E. coli. Mean carbapenem susceptibility was the lowest in K. pneumoniae and E. cloacae. The lowest mean susceptibility to fluoroquinolones was detected in E. coli isolates., Conclusions: This study identified the predominance of E. coli among Enterobacterales in Lebanese patients, with the urinary tract being the most common site of infection and underlined the high rates of AMR in Enterobacterales in Lebanon., Competing Interests: No Conflict of Interest is declared, (Copyright (c) 2023 Mahdi Fadlallah, Elie Salem Sokhn.)

Carbapenem-resistant Enterobacterales (CRE) pathogens have been increasingly isolated and reported in Lebanon. Several studies have been published over the last two decades about the CRE situation in the country. However, compared to the worldwide data, those studies are scarce and mostly restricted to single center studies. In this review, we aim to present a comprehensive and reliable report illustrating the current situation regarding CRE in Lebanon. Variable studies have shown an increasing pattern of carbapenem resistance in Enterobacterales since the first reports of CRE isolates in 2007 and 2008. Escherichia coli and Klebsiella pneumoniae were the most detected ones. The OXA-48 class D carbapenemases were the most prevalent carbapenemases among CRE isolates. Moreover, the emergence of other carbapenemases like the NDM class B carbapenemase has been noticed. Strict infection control measures in hospitals, including the identification of CRE carriers, are needed in Lebanese hospitals since carriage is a potential risk for the spread of CRE in healthcare settings. The dissemination of CRE in the community is noticed and attributed to multiple causes, such as the refugee crisis, water contamination, and antimicrobial misuse. In conclusion, strict infection control measures in healthcare settings, in addition to accurate antimicrobial stewardship program implementation, are urgently needed., Competing Interests: The authors declare that there are no conflicts of interest., (Copyright © 2023 Mahdi Fadlallah et al.)

Background: CMV infection prevalence in kidney transplant recipients (KTR) is reported to be high in the literature, reaching rates of over 80%., Objectives: The primary endpoints were the evaluation of the prevalence, the risks factors, and the effects of CMV infection on graft function and survival, as well as patient survival at three years after kidney transplantation., Material and Methods: We retrospectively reviewed the medical records of 288 kidney transplant patients operated in three Lebanese transplant centers between 1998 and 2017 with three years of follow-up. The patients were divided into two groups: those free of any CMV infection (271 patients (94%); Group I) and those who suffered from CMV infection (17 patients (6%); Group II)., Results: Baseline demographics of the two groups were similar, including recipient and donor gender and age, cause of renal disease, recipient body mass index, pre-transplant fasting blood sugar and dialysis duration, HLA matching between donor and recipient, degree of sensitization in the recipient, type of CMV prophylaxis, maintenance immunosuppression and immunological characteristics. The prevalence of CMV infection is 5.9% among KTR. There were significant differences between the two groups concerning the type of induction therapy and the duration of anti-CMV prophylaxis. The rate of infected patients and infectious episodes were significantly higher in Group II. At 3-years, graft function and survival, patient survival, and the rate of new-onset diabetes were similar between the two groups., Conclusion: The present study is the first to explore the incidence and risk factors of CMV in kidney transplant patients in Lebanon. Comprehensive nationwide studies are therefore necessary to determine the epidemiology and risk factors of CMV infection after kidney transplantation in Lebanon., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Objective: To examine the auditory function in a group of children with type 1 diabetes, and to study the association between hearing impairment and duration of illness, metabolic control and diabetic complication., Methods: Sixty-three diabetic patients below the age of 18 attending the university hospital in Khartoum, Sudan were investigated together with 63 age and sex matched non-diabetic controls. Pure-tone audiometric tests were performed using an Amplaid 300 clinical audiometer in a soundproof room. Both air and bone conduction were tested at frequencies between 250-8000 Hz and 250-4000 Hz respectively. Hearing impairment was noted at auditory threshold above 25 dB in any frequency and the magnitude of hearing loss was assessed according to auditory threshold in conversational frequencies only., Results: The hearing acuity was lower in the diabetic patients than in the control subjects in all tested frequencies, but the differences achieve statistical significance only at middle and high frequencies. The hearing loss was symmetrical, generally mild, and affects both sexes equally. Duration of diabetes, HbA1c concentration, and angiopathic complications showed positive correlation with the increased hearing thresholds; while, age at onset, insulin dose per day, presence of neuropathy, and frequency of DKA and hypoglycaemic episodes were not associated., Conclusion: Hearing loss occurs early in diabetic children and is related to the duration of the disease and the degree of metabolic control. Strict glycemic control might prevent or delay this complication.