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1.
RSC Adv ; 13(27): 18253-18261, 2023 Jun 15.
Article in English | MEDLINE | ID: mdl-37350858

ABSTRACT

Influenza infections are often exacerbated by secondary bacterial infections, primarily caused by Streptococcus pneumoniae. Both respiratory pathogens have neuraminidases that support infection. Therefore, we hypothesized that dual inhibitors of viral and bacterial neuraminidases might be an advantageous strategy for treating seasonal and pandemic influenza pneumonia complicated by bacterial infections. By screening our in-house chemical library, we discovered a new chemotype that may be of interest for a further campaign to find small molecules against influenza. Our exploration of the pyrrolo[2,3-e]indazole space led to the identification of two hit compounds, 6h and 12. These molecules were well-tolerated by MDCK cells and inhibited the replication of H3N2 and H1N1 influenza A virus strains. Moreover, both compounds suppress viral and pneumococcal neuraminidases indicating their dual activity. Given its antiviral activity, pyrrolo[2,3-e]indazole has been identified as a promising scaffold for the development of novel neuraminidase inhibitors that are active against influenza A virus and S. pneumoniae.

2.
Eur J Med Chem ; 188: 112007, 2020 Feb 15.
Article in English | MEDLINE | ID: mdl-31881489

ABSTRACT

Today, there are no medicines to treat enterovirus and rhinovirus infections. In the present study, a series of novel pleconaril derivatives with substitutions in the isoxazole and phenyl rings was synthesized and evaluated for their antiviral activity against a panel of pleconaril-sensitive and -resistant enteroviruses. Studies of the structure-activity relationship demonstrate the crucial role of the N,N-dimethylcarbamoyl group in the isoxazole ring for antiviral activity against pleconaril-resistant viruses. In addition, one or two substituents in the phenyl ring directly impact on the spectrum of antienteroviral activity. The 3-(3-methyl-4-(3-(3-N,N-dimethylcarbamoyl-isoxazol-5-yl)propoxy)phenyl)-5-trifluoromethyl-1,2,4-oxadiazole 10g was among the compounds exhibiting the strongest activity against pleconaril-resistant as well as pleconaril-susceptible enteroviruses with IC50 values from 0.02 to 5.25 µM in this series. Compound 10g demonstrated markedly less CYP3A4 induction than pleconaril, was non-mutagenic, and was bioavailable after intragastric administration in mice. These results highlight compound 10g as a promising potential candidate as a broad spectrum enterovirus and rhinovirus inhibitor for further preclinical investigations.


Subject(s)
Antiviral Agents/pharmacology , Enterovirus/drug effects , Oxadiazoles/pharmacology , Animals , Antiviral Agents/administration & dosage , Antiviral Agents/chemistry , Cell Survival/drug effects , Dose-Response Relationship, Drug , HeLa Cells , Humans , Male , Mice , Mice, Inbred BALB C , Microbial Sensitivity Tests , Molecular Structure , Oxadiazoles/administration & dosage , Oxadiazoles/chemistry , Oxazoles , Structure-Activity Relationship
3.
Berl Munch Tierarztl Wochenschr ; 126(11-12): 491-9, 2013.
Article in German | MEDLINE | ID: mdl-24511824

ABSTRACT

Classical swine fever (CSF) in wild boar repeatedly appeared in different federal states of the Federal Republic of Germany since 1995, from which it has been successfully eradicated sometimes fast, sometimes in a more time taking way using oral immunization as a main element of control. Since 2005 the cases focused solely on North Rhine-Westphalia and Rhineland-Palatinate. In the present study, therefore, the situation of CSF in wild boar has been closely investigated concerning the period 2005 to 2012 in these two regions. It is noteworthy that in this period two different variants of the virus subtype 2.3 occurred in two regionally defined areas of the "Eifel" and "Westerwald" as well as in the "Pfalz". The two Federal States have undertaken extensive oral vaccination campaigns and surveillance activities, which enabled an assessment of the existing virus prevalence and serological prevalence in the different regions. After an initial high serological prevalence, caused probably by interaction of infection and vaccination, the serological levels stabilized seasonally adjusted in a range from 50 to 60% in almost all areas. The vaccination campaigns have been maintained by both Federal States over a period of at least 2.5 years after virus has been detected for the last time. In consequence Germany as a whole has been recognized for the first time to be officially free from CSF in wild boar. By genotyping of virus isolates it has been demonstrated that the virus changed over time and played a role in the outbreak area "Westerwald".


Subject(s)
Classical Swine Fever Virus/immunology , Classical Swine Fever/prevention & control , Vaccination/veterinary , Viral Vaccines/administration & dosage , Administration, Oral , Animals , Antibodies, Viral/blood , Classical Swine Fever/epidemiology , Classical Swine Fever Virus/classification , Classical Swine Fever Virus/genetics , Genotyping Techniques/veterinary , Germany/epidemiology , Seroepidemiologic Studies , Sus scrofa , Swine , Vaccination/methods , Vaccination/standards
4.
Biol Chem ; 390(9): 893-7, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19558322

ABSTRACT

Exogenous application of recombinant TIMP-1 protein modified by addition of a glycosylphosphatidylinositol (GPI) anchor allows efficient insertion of the fusion protein into cell membranes. This 'cell surface engineering' leads to changes in the proteolytic environment. TIMP-1-GPI shows enhanced as well as novel in vitro biological activities including suppression of proliferation, reduced migration, and inhibition of invasion of the colon carcinoma cell line SW480. Treatment of SW480 tumors implanted in Rag (-/-) common gamma chain (-/-) C57BL/6 mice with peritumorally applied TIMP-1-GPI, control rhTIMP-1 protein, or vehicle shows that TIMP-1-GPI leads to a significant reduction in tumor growth.


Subject(s)
Colonic Neoplasms/drug therapy , DNA-Binding Proteins/physiology , Glycosylphosphatidylinositols/therapeutic use , Tissue Inhibitor of Metalloproteinase-1/therapeutic use , Animals , Cell Line, Tumor , Cell Movement/drug effects , Cell Proliferation/drug effects , DNA-Binding Proteins/genetics , Glycosylphosphatidylinositols/chemistry , Humans , Matrix Metalloproteinase 7/metabolism , Matrix Metalloproteinase 9/metabolism , Mice , Mice, Inbred C57BL , Tissue Inhibitor of Metalloproteinase-1/chemistry
5.
Parasitol Res ; 101(1): 219-28, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17385085

ABSTRACT

In August 2006, Bluetongue virus disease (BTD) was detected for the first time in the Netherlands, Belgium, Germany and Northern France. Serological tests as well as reverse transcriptase polymerase chain reaction (RT-PCR) proved the occurrence of Bluetongue virus (BTV) in diseased sheep and cattle, and the virus was identified as serotype 8. Therefore, the search for possible vectors was immediately initiated in the outbreak region in Germany. Traps with automatically regulated ultraviolet light lamps were placed at two different farms with sero-positive cattle, and insect monitoring was done from August 2006 until January 2007. The caught arthropods were weekly determined, and it could be observed that midges of the dipteran family Ceratopogonidae occurred in large numbers, sometimes representing up to 40% of all individuals. The microscopical analysis of the wing morphology showed that the species (complex) Culicoides obsoletus was most abundant covering about 97% of the analysed midges. On the second place ranged C. pulicaris, while C. nubeculosus and C. festivipennis were found only as single individuals. Fed and unfed females were separated, sent to the National Reference Laboratory for Bluetongue disease (Friedrich-Loeffler-Institut, Isle of Riems, Germany) and investigated with a BTV-8-specific real-time RT-PCR. It could be demonstrated that at both farms both fed and unfed C. obsoletus were tested positive for BTV-8 genomes, while none of the other species scored positive. This finding strongly supports that the BTD-epidemic, which reached in the meantime wide regions of North Rhine-Westphalia in Germany and of the neighbouring countries with several hundreds of affected farms, is initiated by virus transmission during the blood meal of midges of the C. obsoletus complex. Since they were captured still at the 21st of December close to cattle with clinical signs, it must be feared that BTV-8 is now established in Central Europe, where it had been absent until now.


Subject(s)
Bluetongue/epidemiology , Ceratopogonidae/virology , Disease Outbreaks/veterinary , Animals , Belgium/epidemiology , Cattle , Cattle Diseases/epidemiology , Cattle Diseases/virology , Ceratopogonidae/anatomy & histology , Female , France/epidemiology , Germany/epidemiology , Male , Netherlands/epidemiology , Sheep , Sheep Diseases/epidemiology , Sheep Diseases/virology , Wings, Animal/anatomy & histology
6.
J Virol ; 80(13): 6629-36, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16775350

ABSTRACT

Recently, it was demonstrated that the coxsackievirus B3 variant PD (CVB3 PD) is able to infect coxsackievirus-adenovirus receptor (CAR)-lacking cells by using heparan sulfates (HS) as additional receptors (A. E. Zautner, U. Korner, A. Henke, C. Badorff, and M. Schmidtke, J. Virol. 77:10071-10077, 2003). For this study, competition experiments with growth factors binding to known HS sequences as well as with specifically desulfated heparins were performed with Chinese hamster ovary cells (CHO-K1) to determine the structural requirements of HS for interaction with CVB3. Hepatocyte growth factor interacting with HS sequences containing [IdUA-GlcNSO(3)(6OSO(3))](n), but not basic fibroblast growth factor binding to [HexUA-GlcNSO(3)-HexUA-GlcNSO(3)-IdUA(2OSO(3))](n), was shown to compete effectively with CVB3 PD for cell surface HS. Whereas unmodified heparin and 2-O-desulfated heparin strongly inhibited the CVB3 PD-induced cytopathic effect, the antiviral activity was markedly reduced after N-, O- and 6-O-desulfation of heparin. Taken together, these results indicate that 6-O- and N-sulfation of GlcNAc of HS is crucial for HS interaction with CVB3 PD and that the disaccharide [IdUA-GlcNSO(3)(6OSO(3))](n) is involved in viral binding. Results from experiments with various inhibitors of endocytic pathways suggest that HS-mediated virus internalization is pH dependent. Despite the fact that CVB3 PD initiates infection about four times slower by making use of HS as a receptor than by using CAR, the time required for a complete viral life cycle in Chinese hamster ovary cells was independent of the utilized receptor.


Subject(s)
Endocytosis/drug effects , Enterovirus B, Human/metabolism , Enterovirus Infections/metabolism , Heparitin Sulfate/pharmacology , Animals , Anticoagulants/pharmacology , CHO Cells , Coxsackie and Adenovirus Receptor-Like Membrane Protein , Cricetinae , Cricetulus , Cytopathogenic Effect, Viral/drug effects , Drug Antagonism , Drug Synergism , Fibroblast Growth Factors/pharmacology , Heparin/pharmacology , Hepatocyte Growth Factor/pharmacology , Humans , Hydrogen-Ion Concentration , Receptors, Virus/deficiency , Time Factors
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