Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) main protease (Mpro) autocatalytically releases itself out of the viral polyprotein to form a fully active mature dimer in a manner that is not fully understood. Here, we introduce several tools to help elucidate differences between cis (intramolecular) and trans (intermolecular) proteolytic processing and to evaluate inhibition of precursor Mpro. We found that many mutations at the P1 position of the N-terminal autoprocessing site do not block cis autoprocessing but do inhibit trans processing. Notably, substituting the WT glutamine at the P1 position with isoleucine retains Mpro in an unprocessed precursor form that can be purified and further studied. We also developed a cell-based reporter assay suitable for compound library screening and evaluation in HEK293T cells. This assay can detect both overall Mpro inhibition and the fraction of uncleaved precursor form of Mpro through separable fluorescent signals. We observed that inhibitory compounds preferentially block mature Mpro. Bofutrelvir and a novel compound designed in-house showed the lowest selectivity between precursor and mature Mpro, indicating that inhibition of both forms may be possible. Additionally, we observed positive modulation of precursor activity at low concentrations of inhibitors. Our findings help expand understanding of the SARS-CoV-2 viral life cycle and may facilitate development of strategies to target precursor form of Mpro for inhibition or premature activation of Mpro.
- MeSH
- antivirové látky * farmakologie chemie MeSH
- farmakoterapie COVID-19 MeSH
- HEK293 buňky MeSH
- inhibitory proteas farmakologie chemie MeSH
- koronavirové proteasy 3C * metabolismus antagonisté a inhibitory chemie genetika MeSH
- lidé MeSH
- mutace MeSH
- objevování léků * metody MeSH
- proteolýza MeSH
- SARS-CoV-2 * enzymologie účinky léků metabolismus genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Dexamethasone 6 mg in patients with severe COVID-19 has been shown to decrease mortality and morbidity. The effects of higher doses of corticosteroid, that would further increase anti-inflammatory effects, are uncertain. The objective of our study was to assess the effect of 20 mg dexamethasone vs. 6 mg dexamethasone intravenously in patients with moderate-to-severe acute respiratory distress syndrome (ARDS) and COVID-19. METHODS: In a multicenter, open-label, randomized trial conducted in nine hospitals in the Czech Republic, we randomized adult patients with ARDS and COVID-19 requiring high-flow oxygen, noninvasive or invasive mechanical ventilation to receive either intravenous high-dose dexamethasone (20 mg/day on days 1-5, 10 mg/day on days 6-10) or standard-dose dexamethasone (6 mg/d, days 1-10). The primary outcome was 28-day ventilator-free days. The five secondary outcomes were 60-day mortality, C-reactive protein dynamics, 14-day WHO (World Health Organization) Clinical Progression Scale score, adverse events and 90-day Barthel index. The long-term outcomes were 180- and 360-day mortality and the Barthel index. The planned sample size was 300, with interim analysis after enrollment of 150 patients. RESULTS: The trial was stopped due to a lack of recruitment, and the follow-up was completed in February 2023. Among 234 randomized patients of 300 planned patients, the primary outcome was available for 224 patients (110 high-dose and 114 standard-dose dexamethasone; median [interquartile range (IQR)] age, 59.0 [48.5-66.0] years; 130 [58.0%] were receiving noninvasive or invasive mechanical ventilation at baseline). The mean number of 28-day ventilator-free days was 8.9 (± 11.5) days for high-dose dexamethasone and 8.0 (± 10.7) days for standard-dose dexamethasone, with an absolute difference of + 0.81 days (95% CI - 2.12-3.73 days). None of the prespecified secondary outcomes, including adverse events, differed between the groups. CONCLUSIONS: Despite not reaching its prespecified enrollment, there was no signal to either benefit or harm high-dose dexamethasone over standard-dose dexamethasone in patients with COVID-19 and moderate-to-severe ARDS. Trial registration Trial registration: ClinicalTrials.gov Identifier: NCT04663555. Registered 10 December 2020, https://clinicaltrials.gov/study/NCT04663555?term=NCT04663555&rank=1 and EudraCT: 2020-005887-70.
- MeSH
- COVID-19 * mortalita komplikace MeSH
- dexamethason * aplikace a dávkování terapeutické užití MeSH
- farmakoterapie COVID-19 * MeSH
- lidé středního věku MeSH
- lidé MeSH
- SARS-CoV-2 MeSH
- senioři MeSH
- syndrom dechové tísně * farmakoterapie mortalita MeSH
- umělé dýchání * MeSH
- výsledek terapie MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- randomizované kontrolované studie MeSH
- Geografické názvy
- Česká republika MeSH
1. elektronické vydání 1 online zdroj (224 stran)
Díky publikaci, kterou právě držíte v rukou, získáte celkový přehled o účetnictví. Pro skutečnou pomoc úplnému začátečníkovi, ale i studentovi nebo i absolventovi rekvalifikačního kurzu je psána srozumitelně a logicky.
1. elektronické vydání 1 online zdroj (216 stran)
Kniha slouží k získání komplexního přehledu o účetnictví. Díky své srozumitelnosti a přehlednosti je vhodná i pro úplné začátečníky. Obsahuje řadu praktických příkladů.
1. elektronické vydání 1 online zdroj (216 stran)
Kniha slouží k získání komplexního přehledu o účetnictví. Díky své srozumitelnosti a přehlednosti je vhodná i pro úplné začátečníky. Obsahuje řadu praktických příkladů.
BACKGROUND: Since December 2019, SARS-CoV-2 virus has infected millions of people worldwide. In patients with COVID-19 pneumonia in need of oxygen therapy or mechanical ventilation, dexamethasone 6 mg per day is currently recommended. However, the dose of 6 mg of dexamethasone is currently being reappraised and may miss important therapeutic potential or may prevent potential deleterious effects of higher doses of corticosteroids. METHODS: REMED is a prospective, open-label, randomised controlled trial testing the superiority of dexamethasone 20 mg (dexamethasone 20 mg on days 1-5, followed by dexamethasone 10 mg on days 6-10) vs 6 mg administered once daily intravenously for 10 days in adult patients with moderate or severe ARDS due to confirmed COVID-19. Three hundred participants will be enrolled and followed up for 360 days after randomization. Patients will be randomised in a 1:1 ratio into one of the two treatment arms. The following stratification factors will be applied: age, Charlson Comorbidity Index, CRP levels and trial centre. The primary endpoint is the number of ventilator-free days (VFDs) at 28 days after randomisation. The secondary endpoints are mortality from any cause at 60 days after randomisation; dynamics of the inflammatory marker, change in WHO Clinical Progression Scale at day 14; and adverse events related to corticosteroids and independence at 90 days after randomisation assessed by the Barthel Index. The long-term outcomes of this study are to assess long-term consequences on mortality and quality of life at 180 and 360 days. The study will be conducted in the intensive care units (ICUs) of ten university hospitals in the Czech Republic. DISCUSSION: We aim to compare two different doses of dexamethasone in patients with moderate to severe ARDS undergoing mechanical ventilation regarding efficacy and safety. TRIAL REGISTRATION: EudraCT No. 2020-005887-70. ClinicalTrials.gov NCT04663555. Registered on December 11, 2020.
- MeSH
- COVID-19 * MeSH
- dexamethason škodlivé účinky MeSH
- dospělí MeSH
- farmakoterapie COVID-19 MeSH
- kvalita života MeSH
- lidé MeSH
- multicentrické studie jako téma MeSH
- prospektivní studie MeSH
- randomizované kontrolované studie jako téma MeSH
- SARS-CoV-2 MeSH
- syndrom dechové tísně * diagnóza farmakoterapie MeSH
- výsledek terapie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- protokol klinické studie MeSH
Viral proteases are indispensable for successful virion maturation, thus making them a prominent drug target. Their enzyme activity is tightly spatiotemporally regulated by expression in the precursor form with little or no activity, followed by activation via autoprocessing. These cleavage events are frequently triggered upon transportation to a specific compartment inside the host cell. Typically, precursor oligomerization or the presence of a co-factor is needed for activation. A detailed understanding of these mechanisms will allow ligands with non-canonical mechanisms of action to be designed, which would specifically modulate the initial irreversible steps of viral protease autoactivation. Binding sites exclusive to the precursor, including binding sites beyond the protease domain, can be exploited. Both inhibition and up-regulation of the proteolytic activity of viral proteases can be detrimental for the virus. All these possibilities are discussed using examples of medically relevant viruses including herpesviruses, adenoviruses, retroviruses, picornaviruses, caliciviruses, togaviruses, flaviviruses, and coronaviruses.
- MeSH
- antivirové látky farmakologie MeSH
- Flavivirus účinky léků metabolismus MeSH
- Herpesviridae účinky léků metabolismus MeSH
- HIV-1 účinky léků MeSH
- inhibitory virových proteáz farmakologie MeSH
- lidé MeSH
- lidské adenoviry účinky léků metabolismus MeSH
- SARS-CoV-2 účinky léků metabolismus MeSH
- virové nemoci farmakoterapie MeSH
- virové proteasy biosyntéza metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
1. elektronické vydání 1 online zdroj (208 stran)
K získání komplexního pohledu na účetnictví slouží právě tato publikace! Určena i pro úplné začátečníky! Její srozumitelnost a přehlednost ocení student účetnictví i absolvent rekvalifikačního kurzu účetnictví.
Chřipka je dobře známé virové onemocnění dýchacích cest. Je třeba odlišit chřipku od chřipce podobných onemocnění a jiných akutních respiračních infekcí. Chřipkové onemocnění může mít komplikovaný průběh, v některých případech vyžaduje hospitalizaci a zahájení antivirové terapie. Komplikace chřipky dělíme na plicní a mimoplicní. Dále můžeme komplikace dělit na primární (způsobené chřipkovým virem) a sekundární (vyvolané druhotnou bakteriální infekcí). Prevence chřipky je pasivní (dodržování osobní hygieny) a aktivní (vakcinace).
Influenza is a well-known viral disease of the respiratory tract. It must be distinguished from influenza-like illnesses and other acute respiratory infections. Influenza may have a complicated course, with some cases requiring hospitalization and initiation of antiviral therapy. Influenza complications are divided into pulmonary and extrapulmonary. Complications can further be divided into primary (caused by an influenza virus) and secondary (caused by secondary bacterial infection). Prevention of influenza is both passive (maintaining personal hygiene) and active (vaccination).
- MeSH
- chřipka lidská * diagnóza komplikace prevence a kontrola MeSH
- lidé MeSH
- neurologické manifestace MeSH
- vakcinace MeSH
- vakcíny proti chřipce MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
OBJECTIVES: The primary objective of this study is to test the hypothesis that administration of dexamethasone 20 mg is superior to a 6 mg dose in adult patients with moderate or severe ARDS due to confirmed COVID-19. The secondary objective is to investigate the efficacy and safety of dexamethasone 20 mg versus dexamethasone 6 mg. The exploratory objective of this study is to assess long-term consequences on mortality and quality of life at 180 and 360 days. TRIAL DESIGN: REMED is a prospective, phase II, open-label, randomised controlled trial testing superiority of dexamethasone 20 mg vs 6 mg. The trial aims to be pragmatic, i.e. designed to evaluate the effectiveness of the intervention in conditions that are close to real-life routine clinical practice. PARTICIPANTS: The study is multi-centre and will be conducted in the intensive care units (ICUs) of ten university hospitals in the Czech Republic. INCLUSION CRITERIA: Subjects will be eligible for the trial if they meet all of the following criteria: 1. Adult (≥18 years of age) at time of enrolment; 2. Present COVID-19 (infection confirmed by RT-PCR or antigen testing); 3. Intubation/mechanical ventilation or ongoing high-flow nasal cannula (HFNC) oxygen therapy; 4. Moderate or severe ARDS according to Berlin criteria: • Moderate - PaO2/FiO2 100-200 mmHg; • Severe - PaO2/FiO2 < 100 mmHg; 5. Admission to ICU in the last 24 hours. EXCLUSION CRITERIA: Subjects will not be eligible for the trial if they meet any of the following criteria: 1. Known allergy/hypersensitivity to dexamethasone or excipients of the investigational medicinal product (e.g. parabens, benzyl alcohol); 2. Fulfilled criteria for ARDS for ≥14 days at enrolment; 3. Pregnancy or breastfeeding; 4. Unwillingness to comply with contraception measurements from enrolment until at least 1 week after the last dose of dexamethasone (sexual abstinence is considered an adequate contraception method); 5. End-of-life decision or patient is expected to die within next 24 hours; 6. Decision not to intubate or ceilings of care in place; 7. Immunosuppression and/or immunosuppressive drugs in medical history: a) Systemic immunosuppressive drugs or chemotherapy in the past 30 days; b) Systemic corticosteroid use before hospitalization; c) Any dose of dexamethasone during the present hospital stay for COVID-19 for ≥5 days before enrolment; d) Systemic corticosteroids during present hospital stay for conditions other than COVID-19 (e.g. septic shock); 8. Current haematological or generalized solid malignancy; 9. Any contraindication for corticosteroid administration, e.g. • intractable hyperglycaemia; • active gastrointestinal bleeding; • adrenal gland disorders; • presence of superinfection diagnosed with locally established clinical and laboratory criteria without adequate antimicrobial treatment; 10. Cardiac arrest before ICU admission; 11. Participation in another interventional trial in the last 30 days. INTERVENTION AND COMPARATOR: Dexamethasone solution for injection/infusion is the investigational medicinal product as well as the comparator. The trial will assess two doses, 20 mg (investigational) vs 6 mg (comparator). Patients in the intervention group will receive dexamethasone 20 mg intravenously once daily on day 1-5, followed by dexamethasone 10 mg intravenously once daily on day 6-10. Patients in the control group will receive dexamethasone 6 mg day 1-10. All authorized medicinal products containing dexamethasone in the form of solution for i.v. injection/infusion can be used. MAIN OUTCOMES: Primary endpoint: Number of ventilator-free days (VFDs) at 28 days after randomisation, defined as being alive and free from mechanical ventilation. SECONDARY ENDPOINTS: a) Mortality from any cause at 60 days after randomisation; b) Dynamics of inflammatory marker (C-Reactive Protein, CRP) change from Day 1 to Day 14; c) WHO Clinical Progression Scale at Day 14; d) Adverse events related to corticosteroids (new infections, new thrombotic complications) until Day 28 or hospital discharge; e) Independence at 90 days after randomisation assessed by Barthel Index. The long-term outcomes of this study are to assess long-term consequences on mortality and quality of life at 180 and 360 days through telephone structured interviews using the Barthel Index. RANDOMISATION: Randomisation will be carried out within the electronic case report form (eCRF) by the stratified permuted block randomisation method. Allocation sequences will be prepared by a statistician independent of the study team. Allocation to the treatment arm of an individual patient will not be available to the investigators before completion of the whole randomisation process. The following stratification factors will be applied: • Age <65 and ≥ 65; • Charlson Comorbidity index (CCI) <3 and ≥3; • CRP <150 mg/L and ≥150 mg/L • Trial centre. Patients will be randomised in a 1 : 1 ratio into one of the two treatment arms. Randomisation through the eCRF will be available 24 hours every day. BLINDING (MASKING): This is an open-label trial in which the participants and the study staff will be aware of the allocated intervention. Blinded pre-planned statistical analysis will be performed. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): The sample size is calculated to detect the difference of 3 VFDs at 28 days (primary efficacy endpoint) between the two treatment arms with a two-sided type I error of 0.05 and power of 80%. Based on data from a multi-centre randomised controlled trial in COVID-19 ARDS patients in Brazil and a multi-centre observational study from French and Belgian ICUs regarding moderate to severe ARDS related to COVID-19, investigators assumed a standard deviation of VFD at 28 days as 9. Using these assumptions, a total of 142 patients per treatment arm would be needed. After adjustment for a drop-out rate, 150 per treatment arm (300 patients per study) will be enrolled. TRIAL STATUS: This is protocol version 1.1, 15.01.2021. The trial is due to start on 2 February 2021 and recruitment is expected to be completed by December 2021. TRIAL REGISTRATION: The study protocol was registered on EudraCT No.:2020-005887-70, and on December 11, 2020 on ClinicalTrials.gov (Title: Effect of Two Different Doses of Dexamethasone in Patients With ARDS and COVID-19 (REMED)) Identifier: NCT04663555 with a last update posted on February 1, 2021. FULL PROTOCOL: The full protocol (version 1.1) is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest of expediting dissemination of this material, the standard formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.
- MeSH
- COVID-19 komplikace terapie MeSH
- délka pobytu MeSH
- dexamethason aplikace a dávkování MeSH
- glukokortikoidy aplikace a dávkování MeSH
- hodnocení ekvivalence jako téma MeSH
- klinické zkoušky, fáze II jako téma MeSH
- lidé MeSH
- multicentrické studie jako téma MeSH
- progrese nemoci MeSH
- randomizované kontrolované studie jako téma MeSH
- SARS-CoV-2 MeSH
- syndrom dechové tísně etiologie terapie MeSH
- umělé dýchání * MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- dopisy MeSH
- protokol klinické studie MeSH