PK/PD investigation of antiviral host matriptase/TMPRSS2 inhibitors in cell models.

Certain corona- and influenza viruses utilize type II transmembrane serine proteases for cell entry, making these enzymes potential drug targets for the treatment of viral respiratory infections. In this study, the cytotoxicity and inhibitory effects of seven matriptase/TMPRSS2 inhibitors (MI-21, MI-463, MI-472, MI-485, MI-1900, MI-1903, and MI-1904) on cytochrome P450 enzymes were evaluated using fluorometric assays. Additionally, their antiviral activity against influenza A virus subtypes H1N1 and H9N2 was assessed. The metabolic depletion rates of these inhibitors in human primary hepatocytes were determined over a 120-min period by LC-MS/MS, and PK parameters were calculated. The tested compounds, with the exception of MI-21, displayed potent inhibition of CYP3A4, while all compounds lacked inhibitory effects on CYP1A2, CYP2C9, CYP2C19, and CYP2D6. The differences between the CYP3A4 activity within the series were rationalized by ligand docking. Elucidation of PK parameters showed that inhibitors MI-463, MI-472, MI-485, MI-1900 and MI-1904 were more stable compounds than MI-21 and MI-1903. Anti-H1N1 properties of inhibitors MI-463 and MI-1900 and anti-H9N2 effects of MI-463 were shown at 20 and 50 µM after 24 h incubation with the inhibitors, suggesting that these inhibitors can be applied to block entry of these viruses by suppressing host matriptase/TMPRSS2-mediated cleavage.

Coating with Hypertonic Saline Improves Virus Protection of Filtering Facepiece Manyfold-Benefit of Salt Impregnation in Times of Pandemic.

Recently, as is evident with the COVID-19 pandemic, virus-containing aerosols can rapidly spread worldwide. As a consequence, filtering facepieces (FFP) are essential tools to protect against airborne viral particles. Incorrect donning and doffing of masks and a lack of hand-hygiene cause contagion by the wearers' own hands. This study aimed to prove that hypertonic saline effectively reduces the infectious viral load on treated masks. Therefore, a hypertonic salt solution´s protective effect on surgical masks was investigated, specifically analyzing the infectivity of aerosolized Alphacoronavirus 1 in pigs (Transmissible Gastroenteritis Virus (TGEV)). Uncoated and hypertonic salt pre-coated FFPs were sprayed with TGEV. After drying, a defined part of the mask was rinsed with the medium, and the eluent was used for the infection of a porcine testicular cell line. Additionally, airborne microorganisms´ long-term infectivity of sodium-chloride in phosphate-buffered saline comprising 5% saccharose was investigated. In the results from an initial Median Tissue Culture Infectious Dose, infection rate of TGEV was minimally reduced by untreated FFP. In contrast, this could be reduced by a factor of 104 if FFPs were treated with hypertonic salt solutions. Airborne pathogens did not contaminate the growth medium if salt concentrations exceeded 5%. We conclude that hypertonic saline is a vital tool for anti-virus protection, exponentially improving the impact of FFPs.

High prevalence, genetic diversity and a potentially novel genotype of Sapelovirus A (Picornaviridae) in enteric and respiratory samples in Hungarian swine farms.

All of the known porcine sapeloviruses (PSVs) currently belong to a single genotype in the genus Sapelovirus (family Picornaviridae). Here, the complete genome of a second, possibly recombinant, genotype of PSV strain SZ1M-F/PSV/HUN2013 (MN807752) from a faecal sample of a paraplegic pig in Hungary was characterized using viral metagenomics and RT-PCR. This sapelovirus strain showed only 64 % nucleotide identity in the VP1 region to its closest PSV-1 relative. Complete VP1 sequence-based epidemiological investigations of PSVs circulating in Hungary showed the presence of diverse strains found in high prevalence in enteric and respiratory samples collected from both asymptomatic and paraplegic pigs from 12 swine farms. Virus isolation attempts using PK-15 cell cultures were successful in 3/8 cases for the classic but not the novel PSV genotype. Sequence comparisons of faeces and isolate strains derived VP1 showed that cultured PSV strains not always represent the dominant PSVs found in vivo.

Frequency of diarrhoea-associated viruses in swine of various ages in Hungary.

Enteric viral diseases of swine are one of the most frequent disorders causing huge economic losses in pork production. After the reappearance of an emerging enteropathogen, porcine epidemic diarrhoea virus (PEDV) in Hungary in 2016, an extensive survey was initiated in an attempt to identify diarrhoea-related porcine viruses, including adeno-, astro-, boca-, calici-, circo-, corona-, kobu-, rota- and Torque teno viruses. A total of 384 faecal samples collected during a twoyear period from diarrhoeic and asymptomatic pigs of various ages in 17 farms were screened by conventional and real-time PCR methods. Half of the samples contained at least one examined virus with the dominance of kobuvirus (55.1%) followed by bocaviruses (33.2%) and rotavirus groups A and C together (20.9%), while coronaviruses including PEDV were not found in this set of samples. Statistical analysis showed a highly significant difference (P < 0.0001) in the frequency of single infections compared to mixed ones with the exception of weaned pigs, in which group additionally most viruses were detected. The results of this study suggest that the complexity of this disease may vary with age, which makes the prevention of diarrhoea a challenge, especially in weaned pigs.

Evaluation of in vitro inhibitory potential of type-I interferons and different antiviral compounds on rabies virus replication.

Five different compounds were tested for their in vitro inhibitory effect against RABV multiplication in mouse neuroblastoma (N2A) cell line. N2A cells were infected with the fixed RABV strain CVS-11 one hour prior to adding antivirals or their respective combinations. The infectious titre of RABV as well as the quantity of viral RNA was determined in the cell culturing medium after 48 h. All five tested compounds (mouse interferon (IFN)-α and -ß, ribavirin, favipiravir (T-705) and sorafenib) reduced viral replication in a concentration-dependent manner: IFN-ß and sorafenib both provided 73.71% relative inhibition of viral replication in the highest non-cytotoxic concentration, while ribavirin caused 48.07%, IFN-α caused 44.87% and favipiravir caused 35.25% relative inhibition, respectively. When applied in combination, their antiviral activity was not synergistic, but a pronounced inhibition was detected when IFN-ß was combined with sorafenib, ribavirin, or favipiravir. The highest antiviral effect was caused by the combination of IFN-ß and sorafenib (77.19% relative inhibition). In other combinations there was an antagonistic effect detected in the reduction of viral replication. The results demonstrate that these compounds can be promising candidates for a potential combination treatment of rabies, noting that some combinations are not favourable in vitro, which makes thorough in vivo studies necessary.

Combination therapy of rabies-infected mice with inhibitors of pro-inflammatory host response, antiviral compounds and human rabies immunoglobulin.

Recent studies demonstrated that inhibitors of pro-inflammatory molecular cascades triggered by rabies infection in the central nervous system (CNS) can enhance survival in mouse model and that certain antiviral compounds interfere with rabies virus replication in vitro. In this study different combinations of therapeutics were tested to evaluate their effect on survival in rabies-infected mice, as well as on viral load in the CNS. C57Bl/6 mice were infected with Silver-haired bat rabies virus (SHBRV)-18 at virus dose approaching LD50 and LD100. In one experimental group daily treatments were initiated 4 h before-, in other groups 48 or 96 h after challenge. In the first experiment therapeutic combination contained inhibitors of tumour necrosis factor-α (infliximab), caspase-1 (Ac-YVAD-cmk), and a multikinase inhibitor (sorafenib). In the treated groups there was a notable but not significant increase of survival compared to the virus infected, non-treated mice. The addition of human rabies immunoglobulins (HRIG) to the combination in the second experiment almost completely prevented mortality in the pre-exposure treatment group along with a significant reduction of viral titres in the CNS. Post-exposure treatments also greatly improved survival rates. As part of the combination with immunomodulatory compounds, HRIG had a higher impact on survival than alone. In the third experiment the combination was further supplemented with type-I interferons, ribavirin and favipiravir (T-705). As a blood-brain barrier opener, mannitol was also administered. This treatment was unable to prevent lethal consequences of SHBRV-18 infection; furthermore, it caused toxicity in treated mice, presumably due to interaction among the components. In all experiments, viral loads in the CNS were similar in mice that succumbed to rabies regardless of treatment. According to the findings, inhibitors of detrimental host response to rabies combined with antibodies can be considered among the possible therapeutic and post-exposure options in human rabies cases.

Metabolites of Lactobacillus plantarum 2142 prevent oxidative stress-induced overexpression of proinflammatory cytokines in IPEC-J2 cell line.

Probiotics have already proven beneficial effects in the treatment of several intestinal infections, but the underlying mechanisms how the probiotics can affect responses of porcine IPEC-J2 enterocytes to oxidative stress remained to be elucidated. The immunomodulatory effect of five bacterial strains (Lactobacillus plantarum 2142, Lactobacillus casei Shirota, Bifidobacterium animalis subsp. lactis BB-12, Bacillus amyloliquefaciens CECT 5940 and Enterococcus faecium CECT 4515) on 1 mM peroxide-triggered upregulation of interleukin (IL)-8 and tumor necrosis factor alpha (TNF-α) level was screened by q RT-PCR. Our data revealed that spent culture supernatant (SCS) of L. plantarum 2142 had significant lowering effect on IL-8 and TNF-α level with concomitant promoting activity on protective Hsp70 gene expression. According to our results, lactic acid (racemic, D: - and L: -lactic acid) and acetic acid produced by lactobacilli had no protective effect in quenching upregulation of proinflammatory cytokines. Furthermore, L. plantarum 2142-specific supernatant peptides were detected by gel electrophoresis and capillary zone electrophoresis.

Tako-tsubo syndrome associated with sexual intercourse.

We present a case of Tako-tsubo syndrome induced by sexual activity. This is the first reported case of reversible left ventricular dysfunction associated with sexual intercourse, which necessitated mechanical ventilation in this female patient with acute heart failure.

N-terminal pro-brain natriuretic peptide and tombstoning ST-segment elevation in patients with anterior wall acute myocardial infarction.

Tombstoning ST-segment elevation myocardial infarction (STEMI) has been associated with a poor prognosis ever since Wimalaratna's first description of this clinical entity, and the reasons for this are not fully understood. We studied 87 consecutive patients who had anterior STEMI (January 2004 to September 2004) to compare the form of STEMI, coronary anatomy, and initial N-terminus pro-brain natriuretic peptide (NT-pro-BNP) level. Patients who had tombstoning STEMI had higher levels of NT-pro-BNP despite significant differences in cardiac enzyme levels or extent of coronary disease. This finding suggests that, in addition to changing the shape of repolarization, decreased microcirculation plays a role in the development of increased wall tension. Increased wall tension in turn is the probable cause of higher NT-pro-BNP levels and increased mortality.

[Acute ST segment elevation during noncardiogenic shock]. / Nem cardiogen shock által indukált tranziens ST-eleváció.

Transient elevation of the ST segment was observed in a patient during noncardiogenic shock. The coronarography was negative. The patient received dopamine infusion. The 48 yr-old man had Crohn disease with septicaemia and ARDS. The exact pathomechanism is not known, but the negative coronarography ruled out the epicardial coronary disease. The suggested mechanisms are dopamine induced coronary vasoconstriction or complement activation.