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Minimum Separators and Menger’s Theorem
No full textMenger’s theorem implies simply the following property: A minimum separator S of non-adjacent vertices u and v in a graph G remains a minimum uv-separator in G- e , for every e∈ E(G[ S] ) . In this paper, we prove the equivalence between Menger’s theorem and this property and so by given an elementary proof of it, we get a new proof of Menger’s theorem. © 2023, The Author(s), under exclusive licence to Springer Nature Japan KK, part of Springer Nature
Epac as a tractable therapeutic target
No full textIn 1957, cyclic adenosine monophosphate (cAMP) was identified as the first secondary messenger, and the first signaling cascade discovered was the cAMP-protein kinase A (PKA) pathway. Since then, cAMP has received increasing attention given its multitude of actions. Not long ago, a new cAMP effector named exchange protein directly activated by cAMP (Epac) emerged as a critical mediator of cAMP's actions. Epac mediates a plethora of pathophysiologic processes and contributes to the pathogenesis of several diseases such as cancer, cardiovascular disease, diabetes, lung fibrosis, neurological disorders, and others. These findings strongly underscore the potential of Epac as a tractable therapeutic target. In this context, Epac modulators seem to possess unique characteristics and advantages and hold the promise of providing more efficacious treatments for a wide array of diseases. This paper provides an in-depth dissection and analysis of Epac structure, distribution, subcellular compartmentalization, and signaling mechanisms. We elaborate on how these characteristics can be utilized to design specific, efficient, and safe Epac agonists and antagonists that can be incorporated into future pharmacotherapeutics. In addition, we provide a detailed portfolio for specific Epac modulators highlighting their discovery, advantages, potential concerns, and utilization in the context of clinical disease entities. © 202
Efficacy of lung cancer screening at the American University of Beirut Medical Center
Get PDFIntroduction: In Lebanon, a dedicated screening program for lung cancer is absent. Screening is largely based on the recommendation of an informed physician or the initiative of a patient. To better understand the situation, it is important to look at the available data on patients currently being screened for lung cancer in this country. Our aim in this study is to review the data and compare it with that in the literature as well as to assess the efficacy of the screening process followed. Methods: Our study accessed the electronic medical records of patients at the American University of Beirut Medical Center (AUBMC), a tertiary care center in Lebanon. We collected information on patients who underwent screening low-dose computed tomography (LDCT) scan between June 2019 and June 2021 inclusive. Records of all patients who underwent a non-contrast computed tomography (CT) scan at AUBMC during this period were collected and analyzed. Results: On average, our population had a 52.6 pack-year smoking history. Moreover, 47% of our population had an accurate pack-year reported, while 12% did not have enough information to even estimate their pack-year history. When looking at the accurate and estimated data, 5% of our population did not even meet the ≥20 pack-year smoking history. Eight patients had positive findings on the screening LDCT, which we defined as suspicious findings that require further workup (e.g., PET/CT or biopsy) or other significant incidental findings. Conclusion: A well-organized program for lung cancer screening in Lebanon is absent. Screening largely depends on the initiative of the physician or the patient. We were able to uncover multiple flaws in the screening method used, including poor documentation and follow-up. Although the screening method adopted retained some benefits in terms of detecting early malignancy, it lacked proper organization and was not ideal. A better, systematized screening program is needed to have optimal outcomes. Copyright © 2023 Harb, Alhafi and Tfayli
Interpersonal conflict and psychological well-being at work: the beneficial effects of teleworking and emotional intelligence
Get PDFPurpose: This cross-sectional study had several objectives. This paper aims to study the direct effect of teleworking on interpersonal conflict, the mediating role that interpersonal conflict can play between teleworking and psychological well-being, the moderating role emotional intelligence (EI) can play between teleworking and interpersonal conflict and whether this moderation effect can, in turn, be associated with psychological well-being (moderated mediation effect). Design/methodology/approach: Path analyses using Mplus software were performed on a sample of 264 employees from 19 small- and medium-sized organizations. Findings: While teleworking was associated with lower interpersonal conflict, it was not associated with enhanced psychological well-being. Interestingly, workload seemed to be associated with higher interpersonal conflict, while decision authority and support garnered from one’s supervisor seemed to be associated with lower interpersonal conflict. Teleworking was indirectly associated with higher psychological well-being via interpersonal conflict. Finally, EI played a moderating role between teleworking and lower interpersonal conflict. This was, in turn, associated with higher psychological well-being. Practical implications: EI is an essential skill to develop in the workplace. Originality/value: A deepened understanding of the role played by EI at work could help organizations to provide positive work environments, both in person and online. This is especially relevant today, with the continued increase in teleworking practices and the resulting rapidly changing interpersonal relationships. © 2023, Emerald Publishing Limited
Office-based blue laser therapy for dyspnea in patients with type 3 Reinke’s edema
Get PDFPurpose: To investigate the effectiveness of in-office blue laser therapy on dyspnea in patients with type 3 Reinke’s edema. Methods: The medical records and video-recordings of patients with Reinke’s edema type 3 who had undergone office-based blue laser therapy between March 2022 and January 2023 were reviewed. The primary outcome measures assessed before and after surgery were dyspnea severity, risk of obstructive sleep apnea (OSA), and disease regression. The severity of dyspnea was measured using the Dyspnea Severity Index (DSI), the risk of OSA was assessed using the STOP-BANG questionnaire, and disease regression was assessed by reviewing the laryngeal examination before and after surgery. The Voice Handicap Index-10 (VHI-10) was used as a secondary outcome measure. Result: A total of 10 patients were included. The mean age of the study population was 58.9 ± 4.2 years. The male-to-female ratio was 2:3. In total, 20 vocal fold lesions were treated among which 18 were reviewed. Eight lesions regressed completely and 10 partially. There was a statistically significant drop in the mean score of DSI after surgery (16.1 ± 10.2 pre-operatively vs 2.3 ± 2.3 post-operatively, p-value < 0.001). The mean STOP-BANG score decreased from 4.8 ± 1.47 to 3.1 ± 1.28 (p-value = 0.001). There was also a significant improvement in VHI-10 score (22.7 ± 7.0 vs 4.4 ± 5.6, p-value < 0.001). Conclusion: Office-based blue laser therapy offers a safe and effective treatment for shortness of breath in patients with type 3 Reinke’s edema. © 2023, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature
How to transform urban institutional green spaces into Ancillary Botanic Gardens to expand informal botanical learning opportunities in cities
Get PDFSince many cities lack botanical gardens, we introduced the concept of Ancillary Botanic Gardens (ABG), which builds on the premise that organizations can expand informal botanical learning by adding a secondary function to their institutional green spaces. This study guides the application of the ABG concept in various spatial and functional contexts by offering practical and interpretive tools to organizations who are less used to working with nature but are interested in mitigating urban residents’ detachment from nature. Online maps of 220 botanic gardens were reviewed to define types of plant collections and produce an exhaustive list of physical botanic garden elements. The collected information was developed into an ABG field checklist that was tested on three case studies in Lebanon and then used to develop guidelines for ABG establishment. The guidelines and checklist are meant to empower and guide organizations interested in establishing an ABG. © 2023, Springer Nature Limited
Pneumonitis in Non-Small Cell Lung Cancer Patients Receiving Atezolizumab Post Chemo-Radiation
Get PDFObjective: The use of Durvalumab following chemoradiotherapy in patients with stage III NSCLC, considerably increased PFS (progression free survival) and OS (overall survival). Unfortunately, Durvalumab is currently not reimbursed for this indication in Lebanon so far. We have used Atezolizumab on a series of patients to the similar mechanism of action. We report in this paper the incidence of pneumonitis using this approach. Methods: We selected from our lung cancer registry, a group of patients diagnosed with stage III NSCLC, who received Atezolizumab (Tecentriq) as consolidation therapy following concurrent chemoradiation therapy. We specifically look at the incidence and severity of pneumonitis based on Common Toxicity Criteria and Adverse Events (CTCAE). Finally, we analyzed patient and tumor characteristics looking for predictive markers for pneumonitis. Result: Of the 14 patients who met our selection criteria, 8 developed pneumonitis and 6 did not. Age, gender and smoking status did not affect the probability of having pneumonitis, with p-values of 0.98,1 and 0.86 respectively. The impact of having PDL-1 status on pneumonitis could not be assessed due to our small sample size. The mean onset of pneumonitis after completion of chemoradiotherapy is 3.62 and after starting Atezolizumab is 2.45 months. Conclusion: The administration of Atezolizumab carries a significant risk of developing pneumonitis following chemoradiation therapy for NSCLC. The presence of certain factors and tumor characteristics might affect the chances of having pneumonitis. However due to our small sample size, definitive conclusions could not be drawn. © This work is licensed under a Creative Commons Attribution-Non Commercial 4.0 International License
The Role of Orthodontics, Orthognathic Surgery and Adjunct Surgical Procedures in the Esthetic Rehabilitation of the Face and Smile: Potential and Limitations
Get PDFFor nearly a century, orthodontists have mainly focused on occlusion as the primary objective of orthodontic therapy. The introduction of the soft tissue paradigm has shifted treatment planning from hard tissue to soft tissue and reinforced the key role of facial esthetics in orthodontic diagnosis and treatment planning. Whereas occlusion is rooted in measurable definitions of Class I and other “keys to occlusion”, esthetics is more subjective, based not only on the orthodontist's assessment but also on personal and cultural preferences rather than rigid norms. The aim in this paper is to demonstrate that orthognathic surgery potentially narrows the gap between esthetics and function, even though surgery may have its own limitations. Three reports are presented on patients whose clinical examination, records evaluation and treatment planning have focused on facial and smile esthetics, and treatment approaches that combined orthodontics, orthognathic surgery and appropriate adjunct procedures to enhance the overall esthetic outcome. © 2023 Elsevier Inc
Identifying Chromatin Binding Sites of Ten Eleven Translocation Protein dTet in Drosophila Melanogaster Central Nervous System
No full textEpigenetics refers to changes in gene expression without changing the DNA sequence and it has been shown to be involved in normal development and disease. There are various mechanisms through which gene expression is modulated and that includes histone modifications, micro-RNA, noncoding RNA and DNA methylation. DNA methylation is the focus of this study, and it refers to the addition of a methyl group on the cytosine residue by a family of DNA methyltransferases (DNMTs). Methylation occurs at CpG sites near gene promoters and silences gene expression. The reverse process, which is DNA demethylation, turns genes “on” and is facilitated by TET proteins as they are involved in the oxidation of 5-methyl cytosine (5mC). There are 3 mammalian TET proteins TET (1-3). Compared to mammals, Drosophila Melanogaster expresses one TET (dTet) that is most similar to TET3 based on sequence similarity in the catalytic domain. dTet is expressed in muscles and imaginal discs in embryos, in neurons during development, and in the brain specifically in the midline glia and optic chiasm of 3rd instar larvae. The substrate of dTet are 5mC on RNA, and 6-methyl Adenine on DNA unlike the mammalian system which is 5mC on both DNA and RNA. In this study we opt to investigate dTet binding to DNA as well as assess m6A mark on DNA of Drosophila brain using chromatin immunoprecipitation sequencing (ChIP-seq). This study will contribute to better understanding of dTet role in gene regulation that could be extrapolated to the mammalian nervous system. The findings of this study could additionally shed light on possible therapeutic targets for many diseases, for example cancer, where gene regulation is disrupted
Impact of International Monetary Funds' Conditionality on Health Sector: A Threat or Opportunity for Lebanon?
No full textK2P Evidence summaries use global research evidence to provide insight on public health priority topics that are ambiguous and have important uncertainty. This document informs policymakers and other stakeholders by synthesizing the best available evidence and presenting its relevance to local contexts. Evidence summaries do not provide recommendations but rather articulate evidence in a clear, objective and factual manner.Includes bibliographical references (pages 41-45)Arabic version: أثر مشروطية صندوق النقد الدولي على قطاع الصحة: تهديد أم فرصة للبنان؟ http://hdl.handle.net/10938/34834Since October 2019, Lebanon has been suffering from an unprecedented economic and financial crisis, exacerbated by political instability in the country, the COVID-19 pandemic, and the Beirut port explosion. The economic and financial crisis in Lebanon is ranked among the top 10 most severe crises globally since the mid-19th century. Lebanon’s economic downfall had a crippling effect on all healthcare sectors, and COVID-19 has further aggravated the crisis. The nation's healthcare system is currently is at a brink of collapse with significant loss of medical staff, a scarcity of medical supplies, and a disruption in the delivery of healthcare. This evidence document aims to answer the following question: What effects will the IMF reforms have on the health sector and what are the implications for Lebanon? The document is structured as follows: 1) overview of the IMF; 2) impact of IMF conditionalities on health system and health systems and outcomes, and 3) implications and way forward for Lebanon