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1.
ACS Infect Dis ; 10(9): 3158-3175, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39096289

RESUMO

SARS-CoV-2 and HCoV-OC43 belong to the same ß genus of the Coronaviridae family. SARS-CoV-2 was responsible for the recent COVID-19 pandemic, and HCoV-OC43 is the etiological agent of mild upper respiratory tract infections. SARS-COV-2 and HCoV-OC43 co-infections were found in children with respiratory symptoms during the COVID-19 pandemic. The two ß-coronaviruses share a high degree of homology between the 3CLpro active sites, so much so that the safer HCoV-OC43 has been suggested as a tool for the identification of new anti-SARS-COV-2 agents. Compounds 5 and 24 inhibited effectively both Wuhan and British SARS-CoV-2 patient isolates in Vero E6 cells and the HCoV-OC43 in MRC-5 cells at low micromolar concentrations. The inhibition was apparently exerted via targeting the 3CLpro active sites of both viruses. Compounds 5 and 24 at 100 µM inhibited the SARS-CoV-2 3CLpro activity of 61.78 and 67.30%, respectively. These findings highlight 5 and 24 as lead compounds of a novel class of antiviral agents with the potential to treat SARS-COV-2 and HCoV-OC43 infections.


Assuntos
Antivirais , Coronavirus Humano OC43 , SARS-CoV-2 , SARS-CoV-2/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/química , Antivirais/síntese química , Humanos , Coronavirus Humano OC43/efeitos dos fármacos , Coronavirus Humano OC43/fisiologia , Chlorocebus aethiops , Animais , Células Vero , Proteases 3C de Coronavírus/antagonistas & inibidores , Tratamento Farmacológico da COVID-19 , COVID-19/virologia , Linhagem Celular
2.
Trends Biochem Sci ; 48(10): 835-838, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37365086

RESUMO

In bacteria, cCMP and cUMP have a key role in defense against infection with bacterial viruses. Bacteriophages encode phosphodiesterases (PDEs; 'nucleases'; Apyc1), which cleave cCMP/cUMP, counteracting this defense. We propose that PDEs are of broader biological relevance, including cCMP/cUMP-cleaving PDEs of eukaryotic viruses, which may constitute new drug targets.


Assuntos
Diester Fosfórico Hidrolases , Viroses , Humanos , CMP Cíclico , Nucleotídeos Cíclicos
3.
J Med Virol ; 95(5): e28769, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37212312

RESUMO

The risk of infection after exposure to clade IIb mpox virus (MPXV) is unknown, and potential presymptomatic shedding of MPXV remains to be demonstrated. High-risk contacts of mpox patients were followed-up in a prospective longitudinal cohort study. Individuals reporting sexual contact, >15 min skin-to-skin contact, or living in the same household with an mpox patient were recruited in a sexual health clinic in Antwerp, Belgium. Participants kept a symptom diary, performed daily self-sampling (anorectal, genital, and saliva), and presented for weekly clinic visits for physical examination and sampling (blood and oropharyngeal). Samples were tested for MPXV by PCR. Between June 24 and July 31, 2022, 25 contacts were included, of which 12/18 (66.0%) sexual and 1/7 (14.0%) nonsexual contacts showed evidence of infection by MPXV-PCR. Six cases had typical mpox symptoms. Viral DNA was detected as early as 4 days before symptom onset in 5 of them. In 3 of these cases, replication-competent virus was demonstrated in the presymptomatic phase. These findings confirm the existence of presymptomatic shedding of replication-competent MPXV and emphasize the high risk of transmission during sexual contact. Sexual contacts of mpox cases should abstain from sex during the incubation period, irrespective of symptoms.


Assuntos
Mpox , Humanos , Estudos Longitudinais , Estudos Prospectivos , Eliminação de Partículas Virais , Instituições de Assistência Ambulatorial
4.
Viruses ; 15(2)2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36851802

RESUMO

Bacteriophage therapy holds promise in addressing the antibiotic-resistance crisis, globally and in Germany. Here, we provide an overview of the current situation (2023) of applied phage therapy and supporting research in Germany. The authors, an interdisciplinary group working on patient-focused bacteriophage research, addressed phage production, phage banks, susceptibility testing, clinical application, ongoing translational research, the regulatory situation, and the network structure in Germany. They identified critical shortcomings including the lack of clinical trials, a paucity of appropriate regulation and a shortage of phages for clinical use. Phage therapy is currently being applied to a limited number of patients as individual treatment trials. There is presently only one site in Germany for large-scale good-manufacturing-practice (GMP) phage production, and one clinic carrying out permission-free production of medicinal products. Several phage banks exist, but due to varying institutional policies, exchange among them is limited. The number of phage research projects has remarkably increased in recent years, some of which are part of structured networks. There is a demand for the expansion of production capacities with defined quality standards, a structured registry of all treated patients and clear therapeutic guidelines. Furthermore, the medical field is still poorly informed about phage therapy. The current status of non-approval, however, may also be regarded as advantageous, as insufficiently restricted use of phage therapy without adequate scientific evidence for effectiveness and safety must be prevented. In close coordination with the regulatory authorities, it seems sensible to first allow some centers to treat patients following the Belgian model. There is an urgent need for targeted networking and funding, particularly of translational research, to help advance the clinical application of phages.


Assuntos
Bacteriófagos , Terapia por Fagos , Humanos , Comércio , Alemanha , Sistema de Registros
5.
ACS Sens ; 8(2): 630-639, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36719711

RESUMO

The emergence of multi-drug-resistant Klebsiella pneumoniae (Kp) strains constitutes an enormous threat to global health as multi-drug resistance-associated treatment failure causes high mortality rates in nosocomial infections. Rapid pathogen detection and antibiotic resistance screening are therefore crucial for successful therapy and thus patient survival. Reporter phage-based diagnostics offer a way to speed up pathogen identification and resistance testing as integration of reporter genes into highly specific phages allows real-time detection of phage replication and thus living host cells. Kp-specific phages use the host's capsule, a major virulence factor of Kp, as a receptor for adsorption. To date, 80 different Kp capsule types (K-serotypes) have been described with predominant capsule types varying between different countries and continents. Therefore, reporter phages need to be customized according to the locally prevailing variants. Recently, we described the autographivirus vB_KpP_TUN1 (TUN1), which specifically infects Kp K64 strains, the most predominant capsule type at the military hospital in Tunis (MHT) that is also associated with high mortality rates. In this work, we developed the highly specific recombinant reporter phage rTUN1::nLuc, which produces nanoluciferase (nLuc) upon host infection and thus enables rapid detection of Kp K64 cells in clinical matrices such as blood and urine. At the same time, rTUN1::nLuc allows for rapid antibiotic susceptibility testing and therefore identification of suitable antibiotic treatment in less than 3 h.


Assuntos
Bacteriófagos , Klebsiella pneumoniae , Humanos , Klebsiella pneumoniae/genética , Fatores de Virulência , Antibacterianos
6.
Infection ; 51(1): 265-270, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35816222

RESUMO

BACKGROUND: Monkeypox is a zoonotic orthopoxvirus infection endemic in central and western Africa. In May 2022, human monkeypox infections including human-to-human transmission were reported in a multi-country outbreak in Europe and North America. CASE PRESENTATIONS: Here we present the first two cases of monkeypox infection in humans diagnosed in Germany. We present clinical and virological findings, including the detection of monkeypox virus DNA in blood and semen. The clinical presentation and medical history of our patients suggest close physical contact during sexual interactions as the route of infection. CONCLUSION: Monkeypox requires rapid diagnosis and prompt public health response. The disease should be considered in the current situation especially the differential diagnosis of vesicular or pustular rash, particularly in patients with frequent sexual contacts. Most importantly, it is essential to raise awareness among all health professionals for the rapid and correct recognition and diagnosis of this disease, which is probably still underreported in Europe (Adler et al. in Lancet Infect Dis https://doi.org/10.1016/s1473-3099(22)00228-6 , 2022).


Assuntos
Mpox , Humanos , Animais , Mpox/diagnóstico , Mpox/epidemiologia , Alemanha/epidemiologia , Europa (Continente) , Zoonoses , Diagnóstico Diferencial
7.
Nat Med ; 28(11): 2288-2292, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35961373

RESUMO

The magnitude of the 2022 multi-country monkeypox virus (MPXV) outbreak has surpassed any preceding outbreak. It is unclear whether asymptomatic or otherwise undiagnosed infections are fuelling this epidemic. In this study, we aimed to assess whether undiagnosed infections occurred among men attending a Belgian sexual health clinic in May 2022. We retrospectively screened 224 samples collected for gonorrhea and chlamydia testing using an MPXV PCR assay and identified MPXV-DNA-positive samples from four men. At the time of sampling, one man had a painful rash, and three men had reported no symptoms. Upon clinical examination 21-37 days later, these three men were free of clinical signs, and they reported not having experienced any symptoms. Serology confirmed MPXV exposure in all three men, and MPXV was cultured from two cases. These findings show that certain cases of monkeypox remain undiagnosed and suggest that testing and quarantining of individuals reporting symptoms may not suffice to contain the outbreak.


Assuntos
Mpox , Saúde Sexual , Masculino , Humanos , Monkeypox virus , Mpox/diagnóstico , Mpox/epidemiologia , Estudos Retrospectivos , Bélgica/epidemiologia
8.
Cell Chem Biol ; 29(9): 1434-1445.e7, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35820417

RESUMO

Bacteriophages are potent therapeutics against biohazardous bacteria, which rapidly develop multidrug resistance. However, routine administration of phage therapy is hampered by a lack of rapid production, safe bioengineering, and detailed characterization of phages. Thus, we demonstrate a comprehensive cell-free platform for personalized production, transient engineering, and proteomic characterization of a broad spectrum of phages. Using mass spectrometry, we validated hypothetical and non-structural proteins and could also monitor the protein expression during phage assembly. Notably, a few microliters of a one-pot reaction produced effective doses of phages against enteroaggregative Escherichia coli (EAEC), Yersinia pestis, and Klebsiella pneumoniae. By co-expressing suitable host factors, we could extend the range of cell-free production to phages targeting gram-positive bacteria. We further introduce a non-genomic phage engineering method, which adds functionalities for only one replication cycle. In summary, we expect this cell-free methodology to foster reverse and forward phage engineering and customized production of clinical-grade bacteriophages.


Assuntos
Bacteriófagos , Bactérias , Farmacorresistência Bacteriana Múltipla , Escherichia coli , Klebsiella pneumoniae , Proteômica
9.
Virus Genes ; 58(3): 188-202, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35347588

RESUMO

Chikungunya virus (CHIKV), a (re)emerging arbovirus, is the causative agent of chikungunya fever. To date, no approved vaccine or specific antiviral therapy are available. CHIKV has repeatedly been responsible for serious economic and public health impacts in countries where CHIKV epidemics occurred. Antiviral tests in vitro are generally performed in Vero-B4 cells, a well characterised cell line derived from the kidney of an African green monkey. In this work we characterised a CHIKV patient isolate from Brazil (CHIKVBrazil) with regard to cell affinity, infectivity, propagation and cell damage and compared it with a high-passage lab strain (CHIKVRoss). Infecting various cell lines (Vero-B4, A549, Huh-7, DBTRG, U251, and U138) with both virus strains, we found distinct differences between the two viruses. CHIKVBrazil does not cause cytopathic effects (CPE) in the human hepatocarcinoma cell line Huh-7. Neither CHIKVBrazil nor CHIKVRoss caused CPE on A549 human lung epithelial cells. The human astrocyte derived glioblastoma cell lines U138 and U251 were found to be effective models for lytic infection with both virus strains and we discuss their predictive potential for neurogenic CHIKV disease. We also detected significant differences in antiviral efficacies regarding the two CHIKV strains. Generally, the antivirals ribavirin, hydroxychloroquine (HCQ) and T-1105 seem to work better against CHIKVBrazil in glioblastoma cells than in Vero-B4. Finally, full genome analyses of the CHIKV isolates were done in order to determine their lineage and possibly explain differences in tissue range and antiviral compound efficacies.


Assuntos
Febre de Chikungunya , Vírus Chikungunya , Glioblastoma , Antivirais/farmacologia , Antivirais/uso terapêutico , Brasil , Linhagem Celular , Vírus Chikungunya/genética , Chlorocebus aethiops , Glioblastoma/genética , Especificidade de Hospedeiro , Humanos , Replicação Viral
10.
Pharmaceuticals (Basel) ; 15(2)2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35215298

RESUMO

Despite numerous advances in personalized phage therapy, smooth logistics are challenging, particularly for multidrug-resistant Gram-negative bacterial infections requiring high numbers of specific lytic phages. We conducted this study to pave the way for efficient logistics for critically ill patients by (1) closely examining and improving a current pipeline under realistic conditions, (2) offering guidelines for each step, leading to safe and high-quality phage supplies, and (3) providing a tool to evaluate the pipeline's efficiency. Due to varying stipulations for quality and safety in different countries, we focused the pipeline on all steps up to a required phage product by a cell-free extract system. The first of three study runs included patients with respiratory bacterial infections from four intensive care units, and it revealed a cumulative time of up to 23 days. Ultimately, adjustment of specific set points of the vulnerable components of the pipeline, phage isolation, and titration increased the pipeline's efficiency by 15% and decreased the maximum required time to 13 days. We present a site-independent practical approach to establish and optimize pipelines for personalized phage delivery, the co-organization of pipeline components between different institutions, non-binding guidelines for every step, and an efficiency check for phage laboratories.

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