Characteristics of medically attended influenza infection across age groups before the COVID-19 pandemic in Lebanon.

Background: Influenza represents a significant global health burden for individuals and society. This study assessed the burden of medically attended influenza at a tertiary medical center in Lebanon to describe the demographics, risk factors, and outcomes prior to the COVID-19 pandemic.

Methods: This was a retrospective review of patients who tested positive for the influenza virus during three seasons between July 1, 2016 to June 30, 2019, at the American University of Beirut Medical Center.

COVID-19 Vaccine Acceptance and Hesitancy Among Health Care Workers in Lebanon.

Background: Lebanon endured its worst economic and financial crisis in 2020-2021. To minimize the impact of COVID-19 pandemic, it is important to improve the overall COVID-19 vaccination rate. Given that vaccine hesitancy among health care workers (HCWs) affects the general population's decision to be vaccinated, our study assessed COVID-19 vaccine acceptance among Lebanon HCWs and identified barriers, demographic differences, and the most trusted sources of COVID-19 information.

Multisystem inflammatory syndrome in children (MIS-C) and "Near MIS-C": A continuum?

Introduction: Reports of multisystem inflammatory syndrome in children (MIS-C), following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, have been increasing worldwide, with an incidence varying significantly across studies based on the definition used for the diagnosis. At our tertiary medical center in Lebanon, we encountered several cases that presented a diagnostic challenge because they mimicked MIS-C but did not meet the US Centers for Disease Control and Prevention (CDC) definition. We decided to review these cases and describe their features in comparison with cases that met the CDC criteria of MIS-C and those that had an alternative diagnosis.

The impact of vaccination on the burden of invasive pneumococcal disease from a nationwide surveillance program in Lebanon: an unexpected increase in mortality driven by non-vaccine serotypes.

Background: The impact of pneumococcal conjugate vaccines (PCVs) on the burden of invasive pneumococcal disease (IPD) and serotype distribution was examined across age groups from data collected by the Lebanese Inter-Hospital Pneumococcal Surveillance Program.

Methods: Between 2005 and 2020, 593 invasive isolates were collected from 79 hospitals throughout Lebanon. Serotypes and antimicrobial resistance (AMR) profiles were identified, and trends compared over 3 eras: PCV7, post-PCV7/ pre-PCV13, and PCV13 eras.

The burden of laboratory-confirmed influenza infection in Lebanon between 2008 and 2016: a single tertiary care center experience.

Background: Influenza is a major cause of morbidity and mortality worldwide. Following the 2009 pandemic, there was widened interest in studying influenza burden in all regions. However, since data from the World Health Organization (WHO) Middle East and North Africa (MENA) region remain limited, we aimed to contribute to the understanding of influenza burden in Lebanon.

Genetic Diversity of Human Rotavirus A Among Hospitalized Children Under-5 Years in Lebanon.

Human rotavirus remains a major cause of gastroenteritis worldwide despite the availability of effective vaccines. In this study, we investigated the genetic diversity of rotaviruses circulating in Lebanon. We genetically characterized the VP4 and VP7 genes encoding the outer capsid proteins of 132 rotavirus-associated gastroenteritis specimens, previously identified in hospitalized children (<5 years) from 2011 to 2013 in Lebanon.

Epidemiology and characteristics of urinary tract infections in children and adolescents.

Background: Urinary tract infections (UTIs) are among the most common infections in the pediatric population. Over the last two decades, antibiotic resistance is increasing significantly as extended spectrum beta lactamase (ESBL) producing organisms are emerging. The aim of this study is to provide a comprehensive view of the epidemiologic characteristics of UTIs in hospitalized children, examine the risk factors of UTIs caused by ESBL-producing organisms, and determine the resistance patterns in the isolated organisms over the last 10 years.

Meningococcal serogroups A, C, W-135, and Y tetanus toxoid conjugate vaccine: a new conjugate vaccine against invasive meningococcal disease.

Invasive meningococcal disease is a serious infection that occurs worldwide. It is caused by Neisseria meningitidis, of which six serogroups (A, B, C, W-135, X, and Y) are responsible for most infections. The case fatality rate of meningococcal disease remains high and can lead to significant sequelae.

Review of meningococcal vaccines with updates on immunization in adults.

Meningococcal disease is a serious and global life-threatening disease. Six serogroups (A, B, C, W-135, X, and Y) account for the majority of meningococcal disease worldwide. Meningococcal polysaccharide vaccines were introduced several decades ago and have led to the decline in the burden of disease.

Prospects and challenges in the introduction of human papillomavirus vaccines in the extended Middle East and North Africa region.

The development of effective and safe human papillomavirus (HPV) vaccines provides a great opportunity to prevent a devastating disease, cervical cancer, and a host of other related diseases. However, the introduction of these vaccines has been slow in the Extended Middle East and North Africa (EMENA) region. Only one country has introduced the vaccine and few countries plan HPV vaccine introduction in the coming 5 years.

Quadrivalent meningococcal serogroups A, C, W, and Y tetanus toxoid conjugate vaccine (MenACWY-TT): a review.

Introduction: Meningococcal disease poses serious health risks globally. The six Neisseria meningitidis serogroups responsible for most of the disease burden are A, B, C, W, X and Y. The case fatality rate remains high worldwide and prevention by vaccination remains the best strategy.

Genetic diversity and antiviral drug resistance of pandemic H1N1 2009 in Lebanon.

Background: In June 2009, the World Health Organization announced the 21st century's first influenza pandemic caused by pandemic influenza H1N1 2009 (H1N1 pdm).

Objectives: Our goal was to analyze antiviral drug resistance and the phylogenetic relationships among hemagglutinin (HA) and neuraminidase (NA) genes of H1N1 pdm samples in Lebanon.

Study Design: Nasopharyngeal swabs were collected from 197 patients with influenza-like illness from May 2009 through January 2010.

Antiviral drug susceptibilities of seasonal human influenza viruses in Lebanon, 2008-09 season.

The emergence of antiviral drug-resistant strains of the influenza virus in addition to the rapid spread of the recent pandemic A(H1N1) 2009 virus highlight the importance of surveillance of influenza in identifying new variants as they appear. In this study, genetic characteristics and antiviral susceptibility patterns of influenza samples collected in Lebanon during the 2008-09 season were investigated. Forty influenza virus samples were isolated from 89 nasopharyngeal swabs obtained from patients with influenza-like illness.

Activated protein C attenuates acute lung injury and apoptosis in a hyperoxic animal model.

Evidence suggests that activated protein C (APC) attenuates acute lung injury (ALI) through antithrombotic and anti-inflammatory mechanisms. The aim of this study was to determine the effects of APC on ALI in adult rats exposed to hyperoxic environment. Rats were divided into control, hyperoxia, hyperoxia + APC, and APC.

Modulation of total ceramide and constituent ceramide species in the acutely and chronically hypoxic mouse heart at different ages.

Ceramide has been implicated in regulatory processes vital for cell survival under different stressors, most notably hypoxia. Little has been done to investigate the contributions of the different ceramide species to the regulation of cell survival. This study aims to highlight the patterns of variation in total ceramide and its species in the growing and hypoxic mouse heart.

De novo N-palmitoylsphingosine synthesis is the major biochemical mechanism of ceramide accumulation following p53 up-regulation.

The tumor suppressor protein p53 and the putative lipid tumor suppressor ceramide play pivotal roles in inducing cell cycle arrest or in driving the cell towards apoptosis. Previously we had shown that, in a p53-dependent model of cell death, ceramide accumulated in a p53-dependent manner [Dbaibo GS, Pushkareva MY, Rachid RA, Alter N, Smyth MJ, Obeid LM, Hannun YA. J Clin Invest 1998;102:329-339].

Arsenic trioxide induces accumulation of cytotoxic levels of ceramide in acute promyelocytic leukemia and adult T-cell leukemia/lymphoma cells through de novo ceramide synthesis and inhibition of glucosylceramide synthase activity.

Background And Objectives: Arsenic trioxide (ATO) is an effective treatment for acute promyelocytic leukemia (APL) and potentially for human T-cell leukemia virus type I (HTLV-I) associated adult T-cell leukemia/lymphoma (ATL). Many cytotoxic drugs induce apoptosis through the generation and accumulation of the sphingolipid breakdown product, ceramide, a coordinator of the cellular response to stress. We, therefore, investigated the contribution of ceramide to the mechanism of action of ATO in APL and ATL.

Apoptosis and the activity of ceramide, Bax and Bcl-2 in the lungs of neonatal rats exposed to limited and prolonged hyperoxia.

Background: The aim of the study is to examine the effect of limited and prolonged hyperoxia on neonatal rat lung. This is done by examining the morphologic changes of apoptosis, the expression of ceramide, an important mediator of apoptosis, the expression of inflammatory mediators represented by IL-1beta and the expression of 2 proto-oncogenes that appear to modulate apoptosis (Bax and Bcl-2).

Methods: Newborn rats were placed in chambers containing room air or oxygen above 90% for 7 days.

The CLN9 protein, a regulator of dihydroceramide synthase.

A new variant of a group of pediatric neurodegenerative diseases known as neuronal ceroid lipofuscinosis (NCL) or Batten disease has been identified. It is termed CLN9-deficient. CLN9-deficient fibroblasts have a distinctive phenotype of rapid growth and increased apoptosis and diminished levels of ceramide, dihydroceramide, and sphingomyelin.

Regulation of the sphingolipid signaling pathways in the growing and hypoxic rat heart.

Sphingolipids (SLs) have a biomodulatory role in physiological as well as pathological cardiovascular conditions. This study aims to assess the variation of SL mediators and metabolizing enzymes in the growing and hypoxic rat heart. Sprague-Dawley rats were placed in a hypoxic environment at birth.

Ceramide regulates SR protein phosphorylation during adenoviral infection.

In this study, we show that adenoviral infection induced accumulation of the sphingolipid ceramide in a dose- and time-dependent manner. This accumulation preceded cell lysis, occurred in the absence of biochemical evidence of apoptosis, and was derived from de novo synthesis of ceramide. An adenovirus mutant that lacks the adenovirus death protein (ADP) produced ceramide accumulation in the absence of cell lysis.

Neonatal neck mass in identical twins: an unusual presentation.

Identical twins were noted to have a soft asymptomatic neck mass, each on the opposite side, at 1 week of age. The mass took a dramatic course 1 week later to present as a neck abscess, yet without systemic symptoms. Ultrasonography was highly suggestive of an infected lymphatic malformation (cystic hygroma).

Human T-cell lymphotropic virus type I-transformed T-cells have a partial defect in ceramide synthesis in response to N-(4-hydroxyphenyl)retinamide.

Treatment with the synthetic retinoid HPR [N-(4-hydroxyphenyl)-retinamide] causes growth arrest and apoptosis in HTLV-I (human T-cell lymphotropic virus type-I)-positive and HTLV-I-negative malignant T-cells. It was observed that HPR-mediated growth inhibition was associated with ceramide accumulation only in HTLV-I-negative cells. The aim of the present study was to investigate the mechanism by which HPR differentially regulates ceramide metabolism in HTLV-I-negative and HTLV-I-positive malignant T-cells.

Ceramide inhibits IL-2 production by preventing protein kinase C-dependent NF-kappaB activation: possible role in protein kinase Ctheta regulation.

The role of the sphingolipid ceramide in modulating the immune response has been controversial, in part because of conflicting data regarding its ability to regulate the transcription factor NF-kappaB. To help clarify this role, we investigated the effects of ceramide on IL-2, a central NF-kappaB target. We found that ceramide inhibited protein kinase C (PKC)-mediated activation of NF-kappaB.