Angiotensin-converting enzyme 2 (ACE2) in COVID-19 and other diseases.

The coronavirus SARS-CoV-2 was detected in isolates of pneumonia patients in January 2020. The virus cannot multiply extracellularly but requires access to the cells of a host organism. SARS-CoV-2 uses angiotensin-converting enzyme 2 (ACE2) as a receptor, to which it docks with its spikes. ACE2 belongs to the renin angiotensin system (RAS), whose inhibitors have been used for years against high blood pressure. Renin is an endopeptidase that is predominantly formed in the juxtaglomerular apparatus of the kidney and cleaves the decapeptide angiotensin I (Ang I) from angiotensinogen. Through the angiotensin-converting enzyme (ACE), another 2 C-terminal amino acids are removed from Ang I, so that finally the active octapeptide angiotensin II (Ang II) is formed. The biological effect of Ang II via the angiotensin II receptor subtype 1 (AT1-R) consists of vasoconstriction, fibrosis, proliferation, inflammation, and thrombosis formation. ACE2 is a peptidase that is a homolog of ACE. ACE2 is predominantly expressed by pulmonary alveolar epithelial cells in humans and has been detected in arterial and venous endothelial cells. In contrast to the dicarboxy-peptidase ACE, ACE2 is a monocarboxypeptidase that cleaves only one amino acid from the C-terminal end of the peptides. ACE2 can hydrolyze the nonapeptide Ang-(1-9) from the decapeptide Ang I and the heptapeptide Ang-(1-7) from the octapeptide Ang II. Ang-(1-7) acts predominantly antagonistically (vasodilatory, anti-fibrotic, anti-proliferative, anti-inflammatory, anti-thrombogenetically) via the G protein-coupled Mas receptor to the AT1-R-mediated effects of Ang II. In the pathogenesis of COVID-19 infection, it is therefore assumed that there is an imbalance due to overstimulation of the AT1 receptor in conjunction with a weakening of the biological effects of the Mas receptor.Copyright © 2022 Dustri-Verlag Dr. K. Feistle.

Jahrestagung der Gesellschaft fur Padiatrische Nephrologie.

The proceedings contain 92 papers. The topics discussed include: cellular and humoral immune responses after SARS-CoV-2 vaccination in pediatric kidney recipients;adult outcomes of childhood-onset idiopathic nephrotic syndrome: findings from a health insurance database;the genetic landscape and clinical spectrum of nephronophthisis and related ciliopathies;translational profiling of developing podocytes during glomerulogenesis;MAGED2 is required under hypoxia for cAMP signaling by inhibiting MDM2-dependent endocytosis of G-Alpha-S;high throughput investigation of the metabolic flux of intact cortical kidney tubules;peritoneal membrane junction and solute transporter expression and function in health, CKD and PD;and Function and interaction of coronavirus ion channel proteins.

Antimalarial phytochemicals as potential inhibitors of SARS-CoV-2 guanine N7-methyltransferase (nsp 14): an integrated computational approach.

The inhibition of capping enzymes such as guanine-N7-methyltransferase (GMT) is an attractive target for regulating viral replication, transcription, virulence, and pathogenesis. Thus, compounds that target the Severe Acute Respiratory Syndrome Corona Virus 2 GMT (S2GMT) will enhance drug development against COVID-19. In this study, an in-house library of 249 phytochemicals from African medicinal plants was screened using computational approaches including homology modeling, molecular docking, molecular dynamic simulations, binding free energy calculations based on molecular mechanics/Poisson-Boltzmann surface area (MMPBSA) and Absorption-Distribution-Metabolism-Excretion-Toxicity (ADMET) analysis for inhibitors of S2GMT. The top-ten ranked phytochemicals (TTRP) obtained from the docking analysis to S2GMT were further docked to SARS-COV N7-MTase. Among the TTRP, the top-four ranked phytocompounds (TFRP) viz: 3 alkaloids (Isocryptolepine, 10'-Hydroxyusambarensine and Isostrychnopentamine) and a flavonoid (Mulberrofuran F) interacted strongly with critical catalytic residues whose interference either reduce or completely abolish N7-MTase activity, indicating their potential as capping machinery disruptors. The interactions of TFRP with the catalytic residues of S2GMT were preserved in a 100 ns simulated dynamic environment, thereby, demonstrating high degree of structural stability. The MMPBSA binding free energy calculations corroborated the docking scores with biscryptolepine having the highest binding free energy to S2GMT. The TFRP showed favourable drug-likeness and ADMET properties over a wide range of molecular descriptors. Therefore, the TFRP can be further explored as potential S2GMT inhibitors in in vitro and in vivo experiments.Communicated by Ramaswamy H. Sarma.

Frequency of SARS-CoV-2 infection in hemodialysis patients

Patients with end-stage chronic kidney disease treated with hemodialysis are at risk of infection and severe course of the new coronavirus infection. This opinion was based on the data obtained as a result of PCR testing during the active phase of the disease with detailed clinical symptoms. However, this diagnostic method does not allow one to fully assess the prevalence of infection in the population. The aim - studying of the frequency of SARS-CoV-2 infection in patients receiving hemodialysis treatment and the spectrum of antiviral antibodies, depending on the nature of the course of COVID-19. Material and methods. 100 patients with chronic kidney disease (stage 5D) treated at the outpatient Dialysis Center (MCVTP) were included in the study by a simple random sample. The assessment of SARS-CoV-2 infection was carried out by analyzing the material of smears obtained from the naso-oropharynx by PCR and blood serum samples by ELISA. The study excluded 14 patients with dubious results for the determination of serological markers SARS-CoV-2 and 1 patient with active infection, who was isolated from the RNA of the virus. Results. IgM and IgG antibodies were detected in 49 (57.6%) of the 85 examined patients. 24 of them (group 1) were diagnosed with COVID-19 infection with typical clinical symptoms 3-9 months ago, and 25 (group 2) had no clinical manifestations of the acute respiratory infection at the appropriate time suggesting an asymptomatic course of the disease. IgM class antibodies were detected with equal frequency in group 1 and in group 2 (33.3 vs 24.0%, respectively, p<0.6). IgG antibodies exclusively to the nucleocapsid N-protein (IgGn) were detected only in the latent form of the disease (32%), while antibodies against the S-protein (spike protein) of the virus (IgGs and IgGn+s) were detected more often in the manifest form compared to the asymptomatic one (100 vs 60%, respectively, p<0.05). Conclusion. In a random cohort of patient receiving hemodialysis treatment, more than half were asymptomatic.Despite a wide range of prevention measures, SARS-CoV-2 infection among patients treated with hemodialysis is more than 2 times higher than in the general population.Copyright © 2021 Geotar Media Publishing Group. All rights reserved.

In silico identification of the potential natural inhibitors of SARS-CoV-2 Guanine-N7 methyltransferase

Background: The outbreak of the COVID-19 pandemic caused by the SARS-CoV-2 has triggered intense scientific research into the possible therapeutic strategies that can combat the ravaging disease. One of such strategies is the inhibition of an important enzyme that affects an important physiological process of the virus. The enzyme, Guanine-N7 Methyltransferase is responsible for the capping of the SARS-CoV-2 mRNA to conceal it from the host's cellular defense. The aim of the study: This study aims at computationally identifying the potential natural inhibitors of the SARS-CoV-2 Guanine-N7 methyltransferase binding at the active site (Pocket 41). Material(s) and Method(s): A library of small molecules was obtained from edible African plants and was molecularly docked against the SARS-CoV-2 Guanine-N7 methyltransferase (QHD43415_13. pdb) using the Pyrx software. Sinefungin, an approved antiviral drug had a binding score of -7.6 kcal/ mol with the target was chosen as a standard. Using the molecular descriptors of the compounds, virtual screening for oral availability was performed using the Pubchem and SWISSADME web tools. The online servers pkCSM and Molinspiration were used for further screening for the pharmacokinetic properties and bioactivity respectively. The molecular dynamic simulation and analyses of the Apo and Holo proteins were performed using the GROMACS software on the Galaxy webserver. Result(s): With a total RMSD of 77.78, average RMSD of 3.704, total regional (active site) RMSF of 30.61, average regional RMSF of 1.91, gyration of 6.9986, and B factor of 696.14, Crinamidine showed the greatest distortion of the target. Conclusion(s): All the lead compounds performed better than the standard while Crinamidine is predicted to show the greatest inhibitory activity. Further tests are required to further investigate the inhibitory activities of the lead compounds.Copyright © 2022 Belgorod State National Research University. All right reserved.

VSV-BASED COVID VACCINE FOR THE PREVENTION OF BREAKTHROUGH SARS-CoV-2 INFECTIONS

Background: More than 12 billion doses of COVID-19 vaccine administrations and over 630 million natural infections should have developed adequate levels of herd immunity over the last three years. However, there have been many new waves of coronavirus infections. The development of safe and effective vaccines to control breakthrough SARS-CoV-2 infections remain an urgent priority. We have developed a recombinant VSV vector-based vaccine to fulfill this worldwide need. Method(s): We have used a recombinant vesicular stomatitis virus (rVSV)-based prime-boost immunization strategy to develop an effective COVID-19 recall vaccine candidate. We have constructed an attenuated recombinant VSV genome carrying the full-length Spike protein gene of SARS-CoV-2. Adding the honeybee melittin signal peptide (msp) at the N-terminus enhanced the protein expression and adding the VSV G protein transmembrane domain and the cytoplasmic tail (Gtc) at the C-terminus of the Spike protein allowed efficient incorporation of the Spike protein into pseudotype VSV. Result(s): In immunized mice, rVSV with chimeric rVSV-msp-S-Gtc induced high levels of potent neutralizing antibodies (nAbs) and CD8+ T cell responses, while the full-length Spike with Gtc proved to be the superior immunogen. More importantly, rVSV-msp-S-Gtc-vaccinated animals were completely protected from subsequent SARS-CoV-2 challenges. Furthermore, rVSV-Wuhan and rVSV-Delta vaccines, and an rVSV-Trivalent (mixed rVSV-Wuhan, -Beta and -Delta) vaccine elicited potent nAbs against live SARS-CoV-2 Wuhan (USAWA1), Beta (B.1.351), Delta (B.1.617.2) and Omicron (B.1.1.529) viruses. Heterologous boosting of rVSV-Wuhan with rVSV-Delta induced strong nAb responses against Delta and Omicron viruses, with the rVSV-Trivalent vaccine consistently inducing effective nAbs against all the SARS-CoV-2 variants tested. All rVSV-msp-S-Gtc vaccines also elicited an immunodominant Spike-specific CD8+ T cell response. Conclusion(s): rVSV vaccines targeting SARS-CoV-2 variants of concern can be considered as an effective booster vaccine in the global fight against COVID-19.

A dual-functional module cellular electrochemical sensing platform for simultaneous detection guanine and xanthine.

The separation of the superimposed electrochemical signals of intracellular guanine (G) and xanthine (X) is difficult, which is great obstacle to the application of cell electrochemistry. In this paper, independent functional modules, G-functional module (G-FM) and X-functional module (X-FM), were constructed by molecular imprinting technology for sensitive detection of G and X without mutual interference, then integrated in dual-functional module cellular electrochemical sensing platform (DMCEP) as signal sensing units. DMCEP transmitted signals of G and X in cells synchronously to two windows by two signal sensing channels, and achieved the separation of superimposed signals of G and X in cells. DMCEP exhibited satisfactory reproducibility with relative standard deviation (RSD) of 3.10 and 2.22 %, repeatability with RSD of 3.72 and 3.05 % for G and X detection, and detection limit 0.05 µΜ for G and 0.06 µΜ for X. Good linear relationships between cell concentrations and the signals of G and X on DMCEP were shown in range of 0.75-85 × 106 and 3-85 × 106 cells/mL, respectively. The growth of MCF-7 cells was tracked by DMCEP, and showed consistent trend with the cell counting method, while the change of cell viability from lag to logarithmic phase captured by DMCEP was earlier than that of cell counting method. This strategy provided the foundation for the establishment of the cell viability electrochemical detection method, and new insights into the simultaneous recording of other analyses with superimposed peak positions and the simultaneous tracking of multiple biomarkers.

Interface of G-quadruplex with both stabilizing and destabilizing ligands for targeting various diseases.

Guanine-rich DNA sequences may fold back into non-canonical four-stranded secondary structures termed as G-quadruplexes. The role of G-quadruplexes has already been well established in different diseases like cancer, neurological and viral disorders etc. Also, several small molecules have been reported, which can influence the involvement of G-quadruplexes either through stabilization or destabilization in the cellular environment. Growing statistics have associated G-quadruplex assemblies to a discrete biological process in vivo, including DNA replication, transcription, genomic stability, and epigenetic regulation. DNA G-quadruplex existence in human telomere is well recognized attractive target for anticancer drugs. G-quadruplex-interactive ligands have been known to prevent telomerase access as well as telomere capping. To the best of our understanding, the role of G-quadruplexes in virology, neuropharmacology, cancer progression and its treatment has not been discussed on a single platform till date. This review aims to enhance our knowledge regarding these magical sticky quadruplex structures, which have been quite significantly proved to be the part of many cellular processes along with their established in vivo existence. Understanding regarding stabilizing or destabilizing ligands of these multistranded guanine quadruplex structures might be proved as the facilitator of drug discovery process for many incurable diseases in future.

COVID-19 AS A CAUSE OF COMA IN ADULT ONSET VANISHING WHITE MATTER DISEASE

A 34 year old female presented with fever, diarrhoea, confusion, and a decline in mobility, having recently tested positive for COVID-19. Her medical history included patent foramen ovale, primary ovarian failure and leukoencephalopathy which had been investigated in her 20s leading to a clinical diagnosis of Vanishing White Matter disease (VWM). On admission she deteriorated rapidly with decreased GCS requiring frequent critical care review. MRI demonstrated mild progression of the cerebral atrophy and slight increase in the 'cystic' changes in the white matter. Lumbar puncture was unremarkable. EEG demonstrated widespread cerebral dysfunction with frontotemporal emphasis but without seizure activity. She was managed with supportive care recovering to her baseline function within days. VWM is a leukodystrophy caused by recessive mutations in eukaryotic initiation factor 2B (eIF2b) complex. Adult onset presentations have been described which have a slowly progressive course. Patients with VWM are known to rapidly decline with fever, and mild head injury occasionally resulting in coma. Our case high-lights the potentially devastating effects of a neurotropic virus such as COVID-19 in VWM, and the need to consider rare genetic disorders in adult patients presenting with extensive white matter abnormalities on MRI and premature ovarian failure.

Never Cared for What They Do: High Structural Stability of Guanine-Quadruplexes in the Presence of Strand-Break Damage

DNA integrity is an important factor that assures genome stability and, more generally, the viability of cells and organisms. In the presence of DNA damage, the normal cell cycle is perturbed when cells activate their repair processes. Although efficient, the repair system is not always able to ensure complete restoration of gene integrity. In these cases, mutations not only may occur, but the accumulation of lesions can either lead to carcinogenesis or reach a threshold that induces apoptosis and programmed cell death. Among the different types of DNA lesions, strand breaks produced by ionizing radiation are the most toxic due to the inherent difficultly of repair, which may lead to genomic instability. In this article we show, by using classical molecular simulation techniques, that compared to canonical double-helical B-DNA, guanine-quadruplex (G4) arrangements show remarkable structural stability, even in the presence of two strand breaks. Since G4-DNA is recognized for its regulatory roles in cell senescence and gene expression, including oncogenes, this stability may be related to an evolutionary cellular response aimed at minimizing the effects of ionizing radiation.

Design of a multi-epitope-based peptide vaccine against the S and N proteins of SARS-COV-2 using immunoinformatics approach

Background: As the new pandemic created by COVID-19 virus created the need of rapid acquisition of a suitable vaccine against SARS-CoV-2 to develop Immunity and to reduce the mortality, the aim of this study was to identify SARS-CoV-2 S protein and N antigenic epitopes by using immunoinformatic methods to design a vaccine against SARS-CoV-2, for which S and N protein-dependent epitopes are predicted. B cell, CTL and HTL were determined based on antigenicity, allergenicity and toxicity that were non-allergenic, non-toxic, and antigenic and were selected for the design of a multi-epitope vaccine structure. Then, in order to increase the safety of Hbd-3 and Hbd-2 as adjuvants, they were connected to the N and C terminals of the vaccine construct, respectively, with a linker. The three-dimensional structure of the structure was predicted and optimized, and its quality was evaluated. The vaccine construct was ligated to MHCI. Finally, after optimizing the codon to increase expression in E. coli K12, the vaccine construct was cloned into pET28a (+) vector. Results: Epitopes which were used in our survey were based on non-allergenic, non-toxic and antigenic. Therefore, 543-amino-acid-long multi-epitope vaccine formation was invented through linking 9 cytotoxic CTL, 5 HTL and 14 B cell epitopes with appropriate adjuvants and connectors that can control the SARS coronavirus 2 infection and could be more assessed in medical scientific researches. Conclusion: We believe that the proposed multi-epitope vaccine can effectively evoke an immune response toward SARS-CoV-2.

Proteomic approaches define rocaglates as translation remodelers with multiple protein targets

Intro: Deregulated protein synthesis is a common trait across solid and hematologic malignancies and an attractive target for cancer therapy. Rocaglates compounds that inhibit eukaryotic initiation factor 4A1 (eIF4A1), the essential DEAD-box RNA helicase that resolves mRNA 5'UTR secondary structures during cap-dependent translation initiation. Rocaglates' unique mechanism of action causes sequence-selective mRNA binding by eIF4A1, clamping the inactive helicase onto the transcript. This suppresses translation globally and affects many oncogenic and pro-survival transcripts in particular. Zotatifin, the first-in class synthetic rocaglate, is currently in Phase I clinical trials for the treatment of solid tumors and as an antiviral against SARS-CoV2. Currently, eIF4A1 and DDX3 are the only reported targets of rocaglate-mediated RNA clamping. Employing unbiased proteomic approaches, we have discovered that rocaglates, thought to act as pure eIF4A/translation inhibitors, extensively remodel the translation machinery and translatome. Additionally, mass-spec interrogation for proteins interacting with specific RNA sequences reveals novel targets of rocaglate-mediated, sequence-specific RNA clamping. Methods: We conducted original mass-spectrometry analyses of translational reprogramming by rocaglates. TMT-pSILAC assessed acute changes in protein production, while MATRIX, which captures high-resolution profiles of the translation machinery, revealed translation factors that drive reprogramming in response to rocaglate exposure. We validated results biochemically, in cellulo, and in vivo using patient-derived xenograft (PDX) mouse models. To probe existing and novel rocaglate RNA-clamping targets, we developed unbiased “clampome” assays - in cellulo protein-RNA-pull downs followed by mass-spec analysis of proteins with increased binding to RNA in the presence of rocaglates. Results: We find rocaglates, including zotatifin, have effects far more complex than simple “translational inhibition” as currently defined. Indeed, translatome analysis by TMT-pSILAC revealed myriad up-regulated proteins that drive hitherto unrecognized cytotoxic mechanisms. The GEF-H1 guanine exchange factor, for example, drives anti-survival RHOA/JNK activation, suggesting novel candidate biomarkers of rocaglate clinical outcomes. Translation-machinery analysis by MATRIX identifed rocaglate-induced dependence on specific translation factors including eEF1ϵ1 that drive remodeling. Novel rocaglate RNA-binding targets revealed by clampome studies remain under detailed evaluation as mediators of drug activities. Discussion: Our original proteome-level interrogation revealed that the complete cellular response to these historical “translation inhibitors” is mediated by comprehensive translational landscape remodeling. Effects on a broader suite of RNA binding proteins than eIF4A1 alone we suggest mediate the potent antitumor activities of these unique compounds, elucidation of which permits development of novel precision approaches to targeted translational deregulation in cancer.

The Impact of COVID-19 On Comorbidities: A Review Of Recent Updates For Combating It.

Coronavirus disease is caused by the SARS-CoV-2 virus. The virus first appeared in Wuhan (China) in December 2019 and has spread globally. Till now, it affected 269 million people with 5.3 million deaths in 224 countries and territories. With the emergence of variants like Omicron, the COVID-19 cases grew exponentially, with thousands of deaths. The general symptoms of COVID-19 include fever, sore throat, cough, lung infections, and, in severe cases, acute respiratory distress syndrome, sepsis, and death. SARS-CoV-2 predominantly affects the lung, but it can also affect other organs such as the brain, heart, and gastrointestinal system. It is observed that 75 % of hospitalized COVID-19 patients have at least one COVID-19 associated comorbidity. The most common reported comorbidities are hypertension, NDs, diabetes, cancer, endothelial dysfunction, and CVDs. Moreover, older and pre-existing polypharmacy patients have worsened COVID-19 associated complications. SARS-CoV-2 also results in the hypercoagulability issues like gangrene, stroke, pulmonary embolism, and other associated complications. This review aims to provide the latest information on the impact of the COVID-19 on pre-existing comorbidities such as CVDs, NDs, COPD, and other complications. This review will help us to understand the current scenario of COVID-19 and comorbidities; thus, it will play an important role in the management and decision-making efforts to tackle such complications.

A Real World Experience of Combined Treatment with Romidepsin and Azacitidine in Patients with Peripheral T-Cell Lymphoma

BACKGROUND Patients with peripheral T-cell lymphoma (PTCL) lack good treatment options, particularly in the relapsed and refractory setting (Mak V et al. J Clin Oncol 2013). The development of the targeted therapies in PTCL has been lagging behind those developed for B cell lymphomas. Our work suggested that combinations of epigenetic therapies can be a safe and effective approach for patients with PTCL, particularly those with T-cell lymphomas with a follicular helper phenotype (Marchi E et al. Br. J Haematol 2015;O'Connor O.A. et al;Blood 2019;Falchi L et al. Blood 2020). While the reason for this is not clear, it is thought recurrent mutations in epigenetic factors, including Ten-Eleven Translocation-2 (TET2), DNA methyl transferase-3A (DNMT3A) and isocitrate dehydrogenase-2 (IDH2) may contribute for their increased vulnerability (Couronné L. et al. N Eng J Med 2012;Lemonnier F et al. Blood 2012). Despite these presumptions, a direct explanation for the sensitivity to epigenetic based treatment remains to be established. OBJECTIVES To evaluate the merits of romidepsin plus subcutaneous azacitidine in patients with PTCL when administered in a ‘real-world’ scenario. METHODS We retrospectively identified PTCL patients that were treated with azacitidine and romidepsin outside of a clinical trial based upon queries regarding off study use. The study was reviewed and approved by each Medical Center Institutional Review Board. We have identified 13 patients world-wide whose pretreatment characteristics are shown in Table 1. These patients were treated using 3 different schedules: Schedule A: azacitidine 75mg/m2 s.c. on days 1-7, romidepsin 14 mg/m2 on day 1, 8 and 15 of a 28 day cycle (total of 6 patients);Schedule B: azacitidine 75mg/m2 s.c. on days 1-5, romidepsin 14 mg/m2 on day 8, 15 and 22 of a 35 day cycle;and Schedule C (total of 2 patients): azacitidine 75mg/m2 s.c. on days 1-7, romidepsin 12-14 mg/m2 on day 8, 15 and 22 of a 28 day cycle (total of 5 patients). RESULTS We retrospectively identified 13 patients that were treated with romidepsin and azacitidine off study. Ten patients had angioimmunoblastic lymphoma (AITL), 2 had adult T-cell leukemia/lymphoma (ATLL) and 1 had PTCL-NOS. Eight of the 13 patients had next generation sequencing performed. Most common mutations found were those of TET2 (5 pts), RHOA (4pts), IDH2 (3pts) and DNMT3A (1 pt). One ATLL patient had mutations in TRAF3, FAT1 and MED12. Among these 13 patients, overall response rate (ORR) was 84% and the complete response rate (CR) was 61%. Median number of cycles was 3 (range 1-12). Treatment was well tolerated but notable adverse effects included nausea, fatigue, rash, neutropenia and thrombocytopenia. One patient experienced febrile neutropenia while another had pulmonary infiltrates (differential diagnosis included drug toxicity versus infection). Thrombocytopenia was the most common reason for dose reduction of romidepsin (to 12mg/m2) or its omission on day 8, 15 or 22. In 3 patients, azacitidine and romidepsin were used to achieve remission prior to allogeneic transplant (range of cycles 1-3), with all 3 patients were in CR at their last disease assessment. One patient died of transplant related mortality 8 months after his allogeneic stem cell transplant. There was 1 patient with AITL (treatment naïve) noted to have progression of disease at first imaging following 2 cycles of romidepsin and azacitidine. On the day of her PET/CT, she was however diagnosed with symptomatic Covid19 infection and was hospitalized. A repeat PET/CT 6 weeks later (without any additional lymphoma treatment) revealed PR. CONCLUSIONS Subcutaneous azacitidine and romidepsin administered in a ‘real-world’ situation is highly effective in patients with relapsed PTCL with tolerable toxicity, and can be used to successfully bridge patients to stem cell transplant. Notably, the efficacy was similar to the one reported on a clinical study with oral azacitidine and romidepsin. [Formula presented] Disclosures: Kalac: Astra Zeneca: Consultancy;Kyowa Kirin Consultancy;Gilead: Consultancy;Johnson and Johnson: Research Funding;Guidepoint: Consultancy;GLG: Consultancy. Tam: Beigene: Research Funding;Janssen: Research Funding;Abbvie: Research Funding;Loxo: Honoraria;Beigene: Honoraria;Janssen: Honoraria;Abbvie: Honoraria. Montanari: Seattle Genetics: Research Funding. O'Connor: Servier: Research Funding;Mundipharma: Honoraria;Myeloid Therapeutics: Current equity holder in publicly-traded company, Honoraria, Membership on an entity's Board of Directors or advisory committees;Kymera: Current equity holder in publicly-traded company, Honoraria, Membership on an entity's Board of Directors or advisory committees;Astex: Research Funding;BMS: Research Funding;Merck: Research Funding;TG Therapeutics: Current Employment, Current equity holder in publicly-traded company. Marchi: BMS: Research Funding;Astex: Research Funding;Merck: Research Funding;Myeloid Therapeutics: Honoraria;Kyowa Kirin: Honoraria;Kymera Therapeutics: Other: Scientific Advisor.

Spectra of Photobiological Inactivation of SARS-CoV-2 by Solar UVB Radiation (280-320 nm)

Primary photoacceptors and spectra of photobiological inactivation of the SARS-CoV-2 molecular structures (genome and S-spike protein) by UVB radiation were determined for the first time based on experimental ground-based observations of the intensity and spectrum of solar UVB radiation in Tomsk (56 degrees 29 ' N, 84 degrees 56.89 ' E) from March 26, 2020, to March 26, 2021, and the analysis of works on the structure and chemical molecular composition of SARS-CoV-2.

TANDEM EUS-GUIDED FINE NEEDLE INJECTION OF INTRACYSTIC SUBMICRON PARTICLE PACLITAXEL (NANOPAC®) AS TREATMENT FOR BRANCH-DUCT IPMN: AN INTERIM SAFETY, PHARMACOKINETIC, AND EFFICACY ANALYSIS

BACKGROUND: Branch duct (BD)-IPMNs with increased risk for malignant transformation are typically treated with surgical resection, and alternate therapies are needed for patients with prohibitive risks for perioperative complications. Injection of cysts with paclitaxel may prevent or reverse transformation, but current formulations are not retained in cysts to provide durable benefit. A Submicron Particle formulation of Paclitaxel (SPP) has been designed to avoid clearance into the systemic circulation and effectively provides a depot effect releasing the drug at constant saturation levels. In this initial study of EUS-guided fine needle injection (FNI) with SPP we evaluated safety, tolerability, pharmacokinetics, and cyst response in BD-IPMNs. METHODS: A diagnosis of BD-IPMNs was confirmed by EUSguided confocal laser endomicroscopy and cyst fluid next generation sequencing. Subjects received EUS-FNI of SPP (15mg/mL concentration) at volumes equal to the aspirated cyst fluid as part of an ongoing clinical trial [NCT03188991] (Study was interrupted due to COVID-19 pandemic). This report covers 5 of the study subjects enrolled at one site. SPP was administered on two occasions 12 weeks apart in 4/5 subjects and once in 1 subject. CT Scans were performed at 0, 12, and 24 weeks to assess changes in cyst size. RESULTS: The mean6standard deviation duration of follow-up from 1st EUS-FNI was 37.3±19.8 weeks. The mean size on CT-Scan of BD-IPMNs at time 0 weeks (1st EUS-FNI) was 3.360.8 cm, 12 weeks (2nd EUS-FNI) was 3.02±1.2 cm, and 24 weeks was 3.15±1.8 cm (Table 1). The mean dosage of SPP injected by EUS-FNI was 75±39 mg for 1st dose and 40.6±15.1 mg for 2nd dose. No dose limiting toxicities, study-related serious adverse events, or clinically significant changes in blood work were observed. The paclitaxel levels (PK) in plasma and cyst fluid is shown in Figure 1. Systemic paclitaxel concentration did not exceed 1 ng/mL at any point post-administration, falling below lower limit of quantitation (25 pg/mL) within, at most, 4 weeks. Cyst fluid analysis confirmed sustained presence of SPP for at least 12 weeks. At baseline evaluation, 4 of 5 subjects had GNAS mutations in cyst fluid (Table 1). In total, DNA mutations (KRAS or GNAS) were not detectable in two of 4 (50%) subjects after EUS-FNI with SPP (Table 1);both subjects (Figure 1) had a dose-dependent high intracystic concentration (> 1000 ng/mL) of SPP immediately prior to 2nd EUS-FNI (week 12). CONCLUSION: EUS-FNI of intracystic SPP appears to be safe and tolerable in patients with BD-IPMNs. SPP is likely retained in these cysts up to 12 weeks in a dose-dependent manner and higher doses are associated with regression of mutations that are specific for BD-IPMNs. Future studies with additional injections and longer-term follow-up are needed to understand the durability of the benefits observed.(Table presented)(figure presented)

Potential molecular link between the ß-amyloid precursor protein (APP) and hypoxanthine-guanine phosphoribosyltransferase (HGprt) enzyme in Lesch-Nyhan disease and cancer.

Lesch-Nyhan disease (LND) is a rare X-linked inherited neurogenetic disorders of purine metabolic in which the cytoplasmic enzyme, hypoxanthine-guanine phosphoribosyltransferase (HGprt) is defective. Despite having been characterized over 60 years ago, however, up to now, there is no satisfactory explanation of how deficits in enzyme HGprt can lead to LND with the development of the persistent and severe self-injurious behavior. Recently, a role for epistasis between the mutated hypoxanthine phosphoribosyltransferase 1 (HPRT1) and the ß-amyloid precursor protein (APP) genes affecting the regulation of alternative APP pre-mRNA splicing in LND has been demonstrated. Furthermore, there were also some reported cases of LND developing thrombosis while APP is an important regulator of vein thrombosis and controls coagulation. Otherwise, the surface expression of HGprt enzyme was also observed in several somatic tissue cancers while APP and the APP-like protein-2 (APLP2) are deregulated in cancer cells and linked to increased tumor cell proliferation, migration, and invasion. The present review provides a discussion about these findings and suggests a potential molecular link between APP and HGprt via epistasis between HPRT1 and APP genes affecting the regulation of alternative APP pre-mRNA splicing. As a perspective, expression vectors for HGprt enzyme and APP are constructed as described in Ref. # 24 (Nguyen KV, Naviaux RK, Nyhan WL (2020) Lesch-Nyhan disease: I. Construction of expression vectors for hypoxanthine-guanine phosphoribosyltransferase (HGprt) enzyme and amyloid precursor protein (APP). Nucleosides Nucleotides Nucleic Acids 39: 905-922), and they could be used as tools for clarification of these issues. In addition, these expression vectors, especially the one with the glycosyl-phosphatidylinositol (GPI) anchor can be used as a model for the construction of expression vectors for any protein targeting to the cell plasma membrane for studying intermolecular interactions and could be therefore useful in the vaccines as well as antiviral drugs development (studying intermolecular interactions between the spike glycoprotein of the severe acute respiratory syndrome coronavirus 2, SARS-CoV-2, as well as its variants and the angiotensin-converting enzyme 2, ACE2, in coronavirus disease 2019 (COVID-19) [43],[44], for example).