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"Girgis, Michael"
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Vertebrate and Invertebrate Animal and New In Vitro Models for Studying Neisseria Biology
2023
The history of Neisseria research has involved the use of a wide variety of vertebrate and invertebrate animal models, from insects to humans. In this review, we itemise these models and describe how they have made significant contributions to understanding the pathophysiology of Neisseria infections and to the development and testing of vaccines and antimicrobials. We also look ahead, briefly, to their potential replacement by complex in vitro cellular models.
Journal Article
Pharmacokinetic and metabolomic studies with a BIO 300 Oral Powder formulation in nonhuman primates
2022
BIO 300, a pharmaceutical formulation of genistein, is being developed as a radiation countermeasure to treat hematopoietic acute radiation syndrome (H-ARS) and the delayed effects of acute radiation exposure (DEARE). Several studies have affirmed its safety and efficacy in alleviating the damaging effects of ionizing radiation. However, dose optimization of any drug has always been an important area of research because unnecessarily high drug doses may result in serious complications. In this study, we assessed the pharmacokinetics (PK) and metabolic profiles of two different doses of a novel solid-dosage formulation of BIO 300 (BIO 300 Oral Powder; 100 mg/kg and 200 mg/kg), when administered orally to nonhuman primates (NHPs). While the T
max
values of both doses remained the same, the area under the curve at 48 h (AUC
0-48
) was tripled by doubling the dose. Additionally, we monitored serum samples for global metabolomic/lipidomic changes using high resolution mass spectrometry followed by functional pathway analysis prior to and at various time points up to 48 h post drug administration. Interestingly, the metabolomic profiles of sera from NHPs that received the lower dose demonstrated a transient perturbation in numerous metabolites between the 4 and 12 h time points. Eventually, the metabolite abundance reverted to near-normal by 48 h. These study results are consistent with our previous studies focused on the PK and metabolomic analysis for parenteral and oral aqueous nanosuspension formulations of BIO 300. This study affirms that administration of a single dose of up to 200 mg/kg of BIO 300 Oral Powder is safe in NHPs and conferred no metabolomic-mediated safety features.
Journal Article
Seriousness and outcomes of reported adverse drug reactions in old and new antiseizure medications: a pharmacovigilance study using EudraVigilance database
by
Bácskay, Ildikó
,
Fekete, Klára
,
Horváth, László
in
adverse drug reaction
,
adverse events
,
Anticonvulsants
2024
Introduction: Epilepsy is a widespread disease requiring long-term drug treatment. The aim of this study was to collect information on reported suspected adverse drug reactions (sADRs) of antiseizure medications (ASMs) and study their seriousness and outcomes in various system organ classifications (SOCs). We intended to compare old and new ASMs’ ADRs. Methods: Using EudraVigilance (EV) database, we extracted line listings of reported sADRs with different ASMs over the period from January 2012 to December 2021. The list of ASMs was compiled according to the Anatomical therapeutic chemical classification system. The Medical Dictionary for Regulatory Activities version 24.0 was used for determining the SOCs of individual reported preferred terms (PTs) sADRs. In addition, we calculated the Reporting Odds Ratio (ROR), 95% confidence interval (95% CI), p-value (statistically significant if p< 0.05) and chi-square statistics. Results: A total of 276,694 reports were contained in the exported line listings which included 1,051,142 individual sADRs reported as PTs such as seizure (3.49%), drug ineffective (2.46%), somnolence (1.32%), dizziness (1.29%) and represented four SOCs: nervous system disorders (19.26%), general disorders and administration site conditions (14.39%), psychiatric disorders (11.29%) and injury, poisoning and procedural complications (9.79). Among patients, the age group between 18 and 64 years had the highest percentage (52.40%), followed by those aged over 64 years (18.75%). Of all the reported PTs, 882,706 (83.98%) had reported seriousness. Old ASMs had a significant positive association with “caused/prolonged hospitalisation” , “congenital anomaly” , “disabling” , “life threatening” and “results in death” , while new ASMS with ‘other medically important condition’ . There were 386 (0.04%) PTs related to Sudden Unexpected Death in Epilepsy (SUDEP). Conclusion: In our study, we examined 10 years’ reported sADRs of ASMs in the EV international database. The majority of PTs were serious. Old ASMs were generally more commonly associated with undesired outcomes and seriousness. Considering their expected seriousness and outcomes, the safety profile of the different ASMs, can play a cardinal role in the selection of ASMs.
Journal Article
Hypoxia-activated neuropeptide Y/Y5 receptor/RhoA pathway triggers chromosomal instability and bone metastasis in Ewing sarcoma
2022
Adverse prognosis in Ewing sarcoma (ES) is associated with the presence of metastases, particularly in bone, tumor hypoxia and chromosomal instability (CIN). Yet, a mechanistic link between these factors remains unknown. We demonstrate that in ES, tumor hypoxia selectively exacerbates bone metastasis. This process is triggered by hypoxia-induced stimulation of the neuropeptide Y (NPY)/Y5 receptor (Y5R) pathway, which leads to RhoA over-activation and cytokinesis failure. These mitotic defects result in the formation of polyploid ES cells, the progeny of which exhibit high CIN, an ability to invade and colonize bone, and a resistance to chemotherapy. Blocking Y5R in hypoxic ES tumors prevents polyploidization and bone metastasis. Our findings provide evidence for the role of the hypoxia-inducible NPY/Y5R/RhoA axis in promoting genomic changes and subsequent osseous dissemination in ES, and suggest that targeting this pathway may prevent CIN and disease progression in ES and other cancers rich in NPY and Y5R.
Ewing sarcoma tumour cells frequently metastasize to the bone but the molecular mechanisms governing this process are not well understood. Here, the authors show that neuropeptide Y/Y5 receptor pathway is activated in the hypoxic tumour microenvironment, which results in cytokinesis defects and chromosomal instability, leading to bone invasion.
Journal Article
Analysis of the metabolomic profile in serum of irradiated nonhuman primates treated with Ex-Rad, a radiation countermeasure
by
Li, Yaoxiang
,
Fatanmi, Oluseyi O.
,
Wise, Stephen Y.
in
631/154/53
,
631/154/53/2421
,
Animal models
2021
To date, the United States Food and Drug Administration (FDA) has approved four drugs to mitigate hematopoietic acute radiation syndrome and all four are repurposed radiomitigators. There are several additional drug candidates currently under evaluation that may also be helpful for use during a widespread emergency. One possible candidate is Ex-Rad, also known as ON01210, a chlorobenzyl sulfone derivative (organosulfur compound), which is a novel, small-molecule kinase inhibitor with demonstrated efficacy in the murine model. In this study, we have evaluated the metabolomic and lipidomic profiles in serum samples of nonhuman primates (NHPs) treated with Ex-Rad after exposure to ionizing radiation. Two different dose administration schedules (Ex-Rad I administered 24 and 36 h post-irradiation, and Ex-Rad II administered 48 and 60 h post-irradiation), were used and evaluated using a global molecular profiling approach. We observed alterations in biochemical pathways relating to inflammation and oxidative stress after radiation exposure that were alleviated in animals that received Ex-Rad I or Ex-Rad II. The results from this study lend credence to the possible radiomitigative effects of this drug possibly via a dampening of metabolism-based tissue injury, thus aiding in recovery of vital, radiation-injured organ systems.
Journal Article
Six years’ experience and trends of serum 25-hydroxy vitamin D concentration and the effect of vitamin D3 consumption on these trends
by
Bácskay, Ildikó
,
Horváth, László
,
Tóth, Béla E.
in
25-Hydroxyvitamin D
,
Circulatory system
,
COVID-19
2023
Introduction: Vitamin D (vitD) deficiency may have importance in some diseases, but there is a lack of data in our country to clarify the current situation. Our aim was to examine the basic characteristics of patients’ vitD status, and the ratio of vitD deficiency and its relation to certain diseases, assess seasonality and trends, and reveal the indirect impact of the COVID-19 pandemic on vitD 3 supplementation at the patient population level. Methods: Anonymized data on 25(OH)D test results were obtained from the clinical data registry of a tertiary teaching hospital covering the period between 1 January 2015 and 30 June 2021. VitD consumption (pharmacy sale) data were retrieved from the database of the National Health Insurance Fund of Hungary in order to calculate the defined daily dose (DDD)/1,000 inhabitants/day. Descriptive statistics and odds ratios with their 95% confidence intervals were calculated. The two-sample t -test and F-test were used to analyze our patients’ data. Significant differences were considered if p <0.05. Results: Altogether, 45,567 samples were investigated; the mean age was 49 ± 19.1 years and 68.4% of them were female subjects. Overall, 20% of all patients had hypovitaminosis D, and just over 7% of patients had vitD deficiency. Male subjects had higher odds for hypovitaminosis or vitD deficiency (65.4 ± 28.2 nmol/L vs. 68.4 ± 28.4 nmol/L; p <0.0001). The mean 25(OH)D concentration has changed during the year, reaching a peak in September and a minimum in February. Patients with diseases of the circulatory system, genitourinary system, certain conditions originating in the perinatal period, and “sine morbo” (i.e., without a disease; such as those aged over 45 years and female teenagers) had statistically higher odds for lower 25(OH)D concentrations ( p <0.00001). VitD consumption showed seasonality, being higher in autumn and winter. A slight increase started in the season of 2017/18, and two huge peaks were detected at the beginning of 2020 and 2021 in association with the COVID-19 waves. Conclusion: Our data are the first to describe data concerning vitD in our region. It reinforces the notion of vitD 3 supplementation for some risk groups and also in healthy individuals. To prevent the winter decline, vitD 3 supplementation should be started in September. This and the results during the COVID-19 pandemic highlight the importance of health education encouraging vitamin D 3 supplementation.
Journal Article
DNA origami presenting the receptor binding domain of SARS-CoV-2 elicit robust protective immune response
2023
Effective and safe vaccines are invaluable tools in the arsenal to fight infectious diseases. The rapid spreading of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) responsible for the coronavirus disease 2019 pandemic has highlighted the need to develop methods for rapid and efficient vaccine development. DNA origami nanoparticles (DNA-NPs) presenting multiple antigens in prescribed nanoscale patterns have recently emerged as a safe, efficient, and easily scalable alternative for rational design of vaccines. Here, we are leveraging the unique properties of these DNA-NPs and demonstrate that precisely patterning ten copies of a reconstituted trimer of the receptor binding domain (RBD) of SARS-CoV-2 along with CpG adjuvants on the DNA-NPs is able to elicit a robust protective immunity against SARS-CoV-2 in a mouse model. Our results demonstrate the potential of our DNA-NP-based approach for developing safe and effective nanovaccines against infectious diseases with prolonged antibody response and effective protection in the context of a viral challenge.
A DNA origami nanoparticle-based vaccine against SARS-Cov-2 co-delivers viral RBD antigen and CpG adjuvant and elicits a robust protective immunity against the virus in a mouse model.
Journal Article
Regenerative Endodontics and Minimally Invasive Dentistry: Intertwining Paths Crossing Over Into Clinical Translation
by
Elnawam, Hisham
,
Abdelmougod, Menatallah
,
Mobarak, Ahmed
in
Antigens
,
Bacteria
,
Bioengineering and Biotechnology
2022
Regenerative endodontic procedures have been described for over a decade as a paradigm shift in the treatment of immature necrotic permanent teeth, owing to their ability to allow root maturation with subsequent enhancement of the tooth’s fracture resistance in addition to the potential for regeneration of vital intracanal tissues. Concomitantly, minimally invasive endodontics is another rising concept with the main concern of preservation of tooth structure. Stemming from their potential to preserve the original tooth structure, both regenerative and minimally invasive endodontics could be considered as two revolutionary sciences with one common goal. Achieving this goal would entail not only employing the appropriate strategies to recreate the ideal regenerative niche but modifying existing concepts and protocols currently being implemented in regenerative endodontics to address two important challenges affecting the outcome of these procedures; conservation of tooth structure and achieving effective disinfection. Therefore, the search for new biomimetic cell-friendly disinfecting agents and strategies is crucial if such a novel integratory concept is to be foreseen in the future. This could be attainable by advocating a new merged concept of “minimally invasive regenerative endodontic procedures (MIREPs),” through modifying the clinical protocol of REPs by incorporating a minimally invasive access cavity design/preparation and biomimetic disinfection protocol, which could enhance clinical treatment outcomes and in the future; allow for personalized disinfection/regeneration protocols to further optimize the outcomes of MIREPs. In this review, we aim to introduce this new concept, its realization and challenges along with future perspectives for clinical implementation.
Journal Article
An optimized method for the isolation of urinary extracellular vesicles for molecular phenotyping: detection of biomarkers for radiation exposure
2022
Background
Urinary extracellular vesicles (EVs) are a source of biomarkers with broad potential applications across clinical research, including monitoring radiation exposure. A key limitation to their implementation is minimal standardization in EV isolation and analytical methods. Further, most urinary EV isolation protocols necessitate large volumes of sample. This study aimed to compare and optimize isolation and analytical methods for EVs from small volumes of urine.
Methods
3 EV isolation methods were compared: ultracentrifugation, magnetic bead-based, and size-exclusion chromatography from 0.5 mL or 1 mL of rat and human urine. EV yield and mass spectrometry signals (Q-ToF and Triple Quad) were evaluated from each method. Metabolomic profiling was performed on EVs isolated from the urine of rats exposed to ionizing radiation 1-, 14-, 30- or 90-days post-exposure, and human urine from patients receiving thoracic radiotherapy for the treatment of lung cancer pre- and post-treatment.
Results
Size-exclusion chromatography is the preferred method for EV isolation from 0.5 mL of urine. Mass spectrometry-based metabolomic analyses of EV cargo identified biochemical changes induced by radiation, including altered nucleotide, folate, and lipid metabolism. We have provided standard operating procedures for implementation of these methods in other laboratories.
Conclusions
We demonstrate that EVs can be isolated from small volumes of urine and analytically investigated for their biochemical contents to detect radiation induced metabolomic changes. These findings lay a groundwork for future development of methods to monitor response to radiotherapy and can be extended to an array of molecular phenotyping studies aimed at characterizing EV cargo.
Journal Article
A multi‐omics approach identifies pancreatic cancer cell extracellular vesicles as mediators of the unfolded protein response in normal pancreatic epithelial cells
by
Banerjee, Partha P.
,
Li, Yaoxiang
,
Trevino, Jose G.
in
Adenocarcinoma
,
Biosynthesis
,
Carcinoma, Pancreatic Ductal - metabolism
2022
Although cancer‐derived extracellular vesicles (cEVs) are thought to play a pivotal role in promoting cancer progression events, their precise effect on neighbouring normal cells is unknown. In this study, we investigated the impact of pancreatic cancer ductal adenocarcinoma (PDAC) derived EVs on recipient non‐tumourigenic pancreatic normal epithelial cells upon internalization. We demonstrate that cEVs are readily internalized and induce endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) in treated normal pancreatic epithelial cells within 24 h. We further show that PDAC cEVs increase cell proliferation, migration, and invasion and that these changes are regulated at least in part, by the UPR mediator DDIT3. Subsequently, these cells release several inflammatory cytokines. Leveraging a layered multi‐omics approach, we analysed EV cargo from a panel of six PDAC and two normal pancreas cell lines, using multiple EV isolation methods. We found that cEVs were enriched for an array of biomolecules which can induce or regulate ER stress and the UPR, including palmitic acid, sphingomyelins, metabolic regulators of tRNA charging and proteins which regulate trafficking and degradation. We further show that palmitic acid, at doses relevant to those found in cEVs, is sufficient to induce ER stress in normal pancreas cells. These results suggest that cEV cargo packaging may be designed to disseminate proliferative and invasive characteristics upon internalization by distant recipient normal cells, hitherto unreported. This study is among the first to highlight a major role for PDAC cEVs to induce stress in treated normal pancreas cells that may modulate a systemic response leading to altered phenotypes. These findings highlight the importance of EVs in mediating disease aetiology and open potential areas of investigation toward understanding the role of cEV lipids in promoting cell transformation in the surrounding microenvironment.
Journal Article