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1.
Int J Mol Sci ; 23(7)2022 Mar 22.
Article in English | MEDLINE | ID: covidwho-1785726

ABSTRACT

Fluorine represents a privileged building block in pharmaceutical chemistry. Diethylaminosulfur-trifluoride (DAST) is a reagent commonly used for replacement of alcoholic hydroxyl groups with fluorine and is also known to catalyze water elimination and cyclic Beckmann-rearrangement type reactions. In this work we aimed to use DAST for diversity-oriented semisynthetic transformation of natural products bearing multiple hydroxyl groups to prepare new bioactive compounds. Four ecdysteroids, including a new constituent of Cyanotis arachnoidea, were selected as starting materials for DAST-catalyzed transformations. The newly prepared compounds represented combinations of various structural changes DAST was known to catalyze, and a unique cyclopropane ring closure that was found for the first time. Several compounds demonstrated in vitro antitumor properties. A new 17-N-acetylecdysteroid (13) exerted potent antiproliferative activity and no cytotoxicity on drug susceptible and multi-drug resistant mouse T-cell lymphoma cells. Further, compound 13 acted in significant synergism with doxorubicin without detectable direct ABCB1 inhibition. Our results demonstrate that DAST is a versatile tool for diversity-oriented synthesis to expand chemical space towards new bioactive compounds.


Subject(s)
Ecdysteroids , Fluorine , Animals , Catalysis , Diethylamines/chemistry , Ecdysteroids/chemistry , Fluorine/chemistry , Mice
2.
PLoS Pathog ; 18(2): e1010268, 2022 02.
Article in English | MEDLINE | ID: covidwho-1753212

ABSTRACT

Next generation sequencing has revealed the presence of numerous RNA viruses in animal reservoir hosts, including many closely related to known human pathogens. Despite their zoonotic potential, most of these viruses remain understudied due to not yet being cultured. While reverse genetic systems can facilitate virus rescue, this is often hindered by missing viral genome ends. A prime example is Lloviu virus (LLOV), an uncultured filovirus that is closely related to the highly pathogenic Ebola virus. Using minigenome systems, we complemented the missing LLOV genomic ends and identified cis-acting elements required for LLOV replication that were lacking in the published sequence. We leveraged these data to generate recombinant full-length LLOV clones and rescue infectious virus. Similar to other filoviruses, recombinant LLOV (rLLOV) forms filamentous virions and induces the formation of characteristic inclusions in the cytoplasm of the infected cells, as shown by electron microscopy. Known target cells of Ebola virus, including macrophages and hepatocytes, are permissive to rLLOV infection, suggesting that humans could be potential hosts. However, inflammatory responses in human macrophages, a hallmark of Ebola virus disease, are not induced by rLLOV. Additional tropism testing identified pneumocytes as capable of robust rLLOV and Ebola virus infection. We also used rLLOV to test antivirals targeting multiple facets of the replication cycle. Rescue of uncultured viruses of pathogenic concern represents a valuable tool in our arsenal for pandemic preparedness.


Subject(s)
Ebolavirus/genetics , Filoviridae Infections/virology , Filoviridae/genetics , Virus Replication , Animals , Cell Line , Chlorocebus aethiops , Genetic Complementation Test , Genome, Viral , Hemorrhagic Fever, Ebola/virology , Host Microbial Interactions , Humans , Inclusion Bodies/virology , Induced Pluripotent Stem Cells/virology , Macrophages/virology , RNA, Viral , Reverse Genetics , Vero Cells , Virion/genetics
3.
Klin Monbl Augenheilkd ; 238(6): 715-720, 2021 Jun.
Article in English | MEDLINE | ID: covidwho-1139766

ABSTRACT

BACKGROUND: To estimate the impact of the COVID-19 pandemic on emergency inpatient volume in a tertiary eye care center in Germany with corneal main subspecialization. MATERIAL AND METHODS: A retrospective review of ocular emergency patients who attended the inpatient unit of the Department of Ophthalmology of Saarland University, Homburg/Saar, Germany during the COVID-19 pandemic, between 1 March and 30 April 2020, in comparison to the same time period in 2019. For each subject, clinical history and surgical reports were reviewed. After 24 March 2020, PCR examinations for SARS-CoV-2 were performed from throat swab specimens in all patients using real-time RT-PCR. RESULTS: Totally, 135 patients were admitted in 2019 and 115 patients in 2020 as emergency cases. The patient age at the time of admission did not differ significantly between the two time periods (63.6 ± 17.9 years vs. 62.5 ± 19.6 years) (p = 0.792), but the average length of hospital stays increased significantly for 2020 (4.0 ± 3.6 vs. 4.4 ± 2.7 days, p = 0.043). The percentage of admissions due to acute corneal hydrops (0% vs. 3.5%) increased significantly from 2019 to 2020 (χ2 = 4.772, p = 0.028), however, there was not a significant difference between the two years for any other diagnosis (χ2 ≤ 3.564, p ≥ 0.059). From 2019 to 2020, the percentage of acute intravitreal anti-VEGF injections decreased significantly (7.9% vs. 1.3%, χ2 = 3.985, p = 0.045), but the proportion of other emergency surgeries did not differ between the two years (χ2 ≤ 3.617, p ≥ 0.057). COVID-19 PCR examination was performed in 66 (57.4%) cases in 2020 and all samples (100%) were negative. CONCLUSIONS: The COVID pandemic did not change emergency inpatient volume in our department, but duration of hospital stay was extended on average by 8 hours, mainly due to additional COVID-19-PCR examinations. The proportion of the most frequently performed surgeries did not change remarkably between 2019 and 2020, but with the introduction of Muraine's sutures in 2019, the percentage of admissions with acute corneal hydrops (with or without subsequent surgery) increased for 2020. No urgent surgery had to be postponed due to the COVID-19 pandemic at our department; all operations were performed successfully.


Subject(s)
COVID-19 , Pandemics , Child, Preschool , Emergency Service, Hospital , Germany/epidemiology , Humans , Inpatients , Retrospective Studies , SARS-CoV-2
4.
Genes (Basel) ; 12(2)2021 01 29.
Article in English | MEDLINE | ID: covidwho-1055035

ABSTRACT

SARS-CoV-2 is a recently emerged, novel human coronavirus responsible for the currently ongoing COVID-19 pandemic. Recombination is a well-known evolutionary strategy of coronaviruses, which may frequently result in significant genetic alterations, such as deletions throughout the genome. In this study we identified a co-infection with two genetically different SARS-CoV-2 viruses within a single patient sample via amplicon-based next generation sequencing in Hungary. The recessive strain contained an 84 base pair deletion in the receptor binding domain of the spike protein gene and was found to be gradually displaced by a dominant non-deleterious variant over-time. We have identified the region of the receptor-binding domain (RBD) that is affected by the mutation, created homology models of the RBDΔ84 mutant, and based on the available experimental data and calculations, we propose that the mutation has a deteriorating effect on the binding of RBD to the angiotensin-converting enzyme 2 (ACE2) receptor, which results in the negative selection of this variant. Extending the sequencing capacity toward the discovery of emerging recombinant or deleterious strains may facilitate the early recognition of novel strains with altered phenotypic attributes and understanding of key elements of spike protein evolution. Such studies may greatly contribute to future therapeutic research and general understanding of genomic processes of the virus.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , SARS-CoV-2/genetics , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/metabolism , Amino Acid Sequence , Animals , Base Sequence , Binding Sites , COVID-19/metabolism , COVID-19/virology , Cell Line , Chlorocebus aethiops , Computer Simulation , Humans , Pandemics , Protein Binding , Protein Domains , Sequence Deletion , Vero Cells
5.
Viruses ; 12(12)2020 12 06.
Article in English | MEDLINE | ID: covidwho-967433

ABSTRACT

Severe Acute Respiratory Syndrome Coronavirus 2 is the third highly pathogenic human coronavirus in history. Since the emergence in Hubei province, China, during late 2019, the situation evolved to pandemic level. Following China, Europe was the second epicenter of the pandemic. To better comprehend the detailed founder mechanisms of the epidemic evolution in Central-Eastern Europe, particularly in Hungary, we determined the full-length SARS-CoV-2 genomes from 32 clinical samples collected from laboratory confirmed COVID-19 patients over the first month of disease in Hungary. We applied a haplotype network analysis on all available complete genomic sequences of SARS-CoV-2 from GISAID database as of 21 April 2020. We performed additional phylogenetic and phylogeographic analyses to achieve the recognition of multiple and parallel introductory events into our region. Here, we present a publicly available network imaging of the worldwide haplotype relations of SARS-CoV-2 sequences and conclude the founder mechanisms of the outbreak in Central-Eastern Europe.


Subject(s)
COVID-19/epidemiology , Disease Outbreaks , RNA, Viral/genetics , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Sequence Analysis, DNA , COVID-19/virology , China/epidemiology , Europe/epidemiology , Europe, Eastern/epidemiology , Gene Regulatory Networks , Genome, Viral , Humans , Hungary/epidemiology , Oropharynx/virology
6.
J Neurointerv Surg ; 12(9): 829-830, 2020 09.
Article in English | MEDLINE | ID: covidwho-721215
7.
Geroscience ; 42(5): 1229-1236, 2020 10.
Article in English | MEDLINE | ID: covidwho-695497

ABSTRACT

Coronavirus disease 2019 (COVID-19) is a highly contagious infectious disease caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). From the epidemiological data, the picture emerges that the more severe etiopathologies among COVID-19 patients are found in elderly people. The risk of death due to COVID-19 increases exponentially with age. Eight out of 10 COVID-19 related deaths occur in people older than 65 years of age. Older patients with comorbid conditions such as hypertension, heart failure, diabetes mellitus, asthma, chronic obstructive pulmonary disease, and cancer have a much higher case fatality rate. Governments and public health authorities all over the world have realized that protections of vulnerable older adults should be a priority during the COVID-19 pandemic. COVID-19 is a zoonotic disease. The SARS-CoV-2 virus was originally transmitted likely from a bat or a pangolin to humans. Recent evidence suggests that SARS-CoV-2, similar to other coronaviruses, can infect several species of animals, including companion animals such as dogs, cats, and ferrets although their viral loads remain low. While the main source of infection transmission therefore is human to human, there are a few rare cases of pets contracting the infection from a SARS-CoV-2-infected human. Although there is no evidence that pets actively transmit SARS-CoV-2 via animal-to-human transmission, senior pet ownership potentially may pose a small risk to older adults by (1) potentially enabling animal-to-human transmission of SARS-CoV-2 in the most vulnerable population and (2) by increasing the exposition risk for the elderly due to the necessity to care for the pet and, in the case of dogs, to take them outside the house several times per day. In this overview, the available evidence on SARS-CoV-2 infection in pets is considered and the potential for spread of COVID-19 from companion animals to older individuals and the importance of prevention are discussed.


Subject(s)
Betacoronavirus , Coronavirus Infections/transmission , Disease Transmission, Infectious/statistics & numerical data , Pandemics , Pneumonia, Viral/transmission , Zoonoses/transmission , Animals , COVID-19 , Coronavirus Infections/epidemiology , Humans , Pneumonia, Viral/epidemiology , SARS-CoV-2 , Zoonoses/epidemiology
8.
Geroscience ; 42(4): 1093-1099, 2020 Aug.
Article in English | MEDLINE | ID: covidwho-291453

ABSTRACT

The global impact of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is significant in terms of public health effects and its long-term socio-economic implications. Among all social groups, the elderly is by far the most affected age group regarding morbidity and mortality. In multiple countries spanning several continents, there are an increasing number of reports referencing the novel coronavirus disease-2019 (COVID-19) spread among nursing homes. These areas are now recognized as potent hotspots regarding the pandemic, which one considers with special regard. Herein, we present currently available data of fatal COVID-19 cases throughout Hungary, along with the analysis of the co-morbidity network. We also report on viral genomic data originating from a nursing home resident. The genomic data was used for viral haplotype network analysis. We emphasize the urgent need for public health authorities to focus on nursing homes and residential service units worldwide, especially in the care of the elderly and infirmed. Our results further emphasize the recent statement released by the World Health Organization (WHO) regarding the vulnerability among seniors and especially the high risk of COVID-19 emergence throughout nursing and social homes.

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