A COVID–19-fertőzés és a védőoltások hatásosságának vizsgálata egészségügyi dolgozókon

Bevezetés: A COVID–19-pandémiát okozó SARS-CoV-2 koronavírusnak folyamatosan újabb variánsai jelennek meg, 2021. november óta a legtöbb fertőzést az omikron koronavírus-variáns okozta. Célkitűzés: A prospektív megfigyeléses kohorszvizsgálat célja a COVID–19-fertőzésre nagyobb rizikóval bíró, egész- ségügyben dolgozók körében két Pfizer–BioNTech-vakcina és az ezt követően önkéntesen felvett emlékeztető vakcina utáni COVID–19-fertőzések előfordulásának, a vakcina hatásosságának, biztonságosságának és immunogenitásá- nak vizsgálata volt. Módszer: A Betegápoló Irgalmasrend Budai Irgalmasrendi Kórháza egészségügyi és egészségügyben dolgozó munka- társainak két Pfizer–BioNTech (BNT162b2)-oltását 2021. január 7. és március 8. között kezdték meg. A harmadik, emlékeztető védőoltás típusának választása és időpontjának meghatározása önkéntes volt. 2021. január 7. és 2022. június 29. között követtük nyomon a dolgozókat. Felmértük a COVID–19-fertőzés előfordulását, az oltási reakció súlyosságát, a fertőzésre hajlamosító tényezőket és az oltások után a ’spike’ (S)-protein és a nukleokapszid (N)-protein elleni ellenanyag szintjének változási kinetikáját. Eredmények: 294 dolgozó – 96 orvos, 127 nővér és 71, egészségügyben dolgozó – adatait elemeztük, akiknek leg- alább három ellenanyagszint-mérésük történt a megfigyelési idő alatt. A harmadik, emlékeztető oltást 280 dolgozó kapta meg, a vakcinák megoszlása a következő volt: Pfizer–BioNTech (BNT162b2) (n = 210), Moderna COVID–19 (mRNA-1273) (n = 37), Sinopharm COVID–19 (n = 21), Janssen COVID–19 (n = 10) és AstraZeneca (ChAdOx1 nCoV-19) (n = 2). A megfigyelési időszakban 121 esetben történt fertőzés (41%). A COVID–19-fertőzések lefolyása többségében enyhe volt (97%), egy hét alatt gyógyult. A vizsgált időszakban 2 dolgozó halt meg: egy 56 éves nő két oltás után, COVID–19-fertőzéssel összefüggésbe nem hozható okból, és egy 58 éves férfi, aki a harmadik Pfizer-védőoltás után 6 hónappal zajló COVID–19-fertőzés után elhunyt. A fertőzés előfordulását nem befolyásolta az életkor, a nem, a kísérő betegségek, a dohányzás, a munkakör és a BMI. Az S-ellenanyag szintjének medián értéke az alapimmunizálás második oltása után 1 hónapig emelkedett (medián: 1173,0 U/ml), a 8. hónapig lassú csökkenő tendenciát mutatott (678,5–625,8–538,0 U/ml). A harmadik oltás után 1 hónappal lényegesen emelkedett az S-ellenanyag szintjének medián értéke (16 535,0 U/ml), az oltás utáni 3. hónaptól csökkenő tendenciát mutatott (9697,7 U/ml). Az S-antitest szintjének az oltások utáni kiugróan magas emelkedése összefüggést mutat az előzetes COVID–19-fertőzéssel. Az N-protein elleni ellenanyagszintet az oltás nem befolyásolta, emelkedése a fertőzéssel mutat összefüggést. Következtetés: Az emlékeztető vakcináció kevésbé hatott az omikron variáns okozta fertőzésre, de a betegség lefolyása enyhébb volt. Az alapimmunizáláshoz képest az emlékeztető oltás az S-antitest szintjének jelentősebb emelkedését okozta, ami összefüggést mutat a korábbi COVID–19-fertőzéssel

Lack of Small Intestinal Dysbiosis Following Long-Term Selective Inhibition of Cyclooxygenase-2 by Rofecoxib in the Rat

Intestinal dysbiosis is linked to numerous gastrointestinal disorders, including inflammatory bowel diseases. It is a question of debate if coxibs, selective inhibitors of cyclooxygenase (COX)-2, cause dysbiosis. Therefore, in the present study, we aimed to determine the effect of long-term (four weeks) selective inhibition of COX-2 on the small intestinal microbiota in the rat. In order to avoid mucosal damage due to topical effects and inflammation-driven microbial alterations, rofecoxib, a nonacidic compound, was used. The direct inhibitory effect of rofecoxib on the growth of bacteria was ruled out in vitro. The mucosa-sparing effect of rofecoxib was confirmed by macroscopic and histological analysis, as well as by measuring the intestinal levels of cytokines and tight junction proteins. Deep sequencing of bacterial 16S rRNA revealed that chronic rofecoxib treatment had no significant influence on the composition and diversity of jejunal microbiota. In conclusion, this is the first demonstration that long-term selective inhibition of COX-2 by rofecoxib does not cause small intestinal dysbiosis in rats. Moreover, inhibition of COX-2 activity is not likely to be responsible per se for microbial alterations caused by some coxibs, but other drug-specific properties may contribute to it

Hidden Cardiotoxicity of Rofecoxib Can be Revealed in Experimental Models of Ischemia/Reperfusion

Cardiac adverse effects are among the leading causes of the discontinuation of clinical trials and the withdrawal of drugs from the market. The novel concept of 'hidden cardiotoxicity' is defined as cardiotoxicity of a drug that manifests in the diseased (e.g. ischemic/reperfused), but not in the healthy heart or as a drug-induced deterioration of cardiac stress adaptation (e.g. ischemic conditioning). Here, we aimed to test if the cardiotoxicity of a selective COX-2 inhibitor rofecoxib that was revealed during its clinical use, i.e., increased occurrence of proarrhythmic and thrombotic events, could have been revealed in early phases of drug development by using preclinical models of ischemia/reperfusion (I/R) injury. Rats that were treated with rofecoxib or vehicle for four weeks were subjected to 30 min. coronary artery occlusion and 120 min. reperfusion with or without cardioprotection that is induced by ischemic preconditioning (IPC). Rofecoxib increased overall the arrhythmias including ventricular fibrillation (VF) during I/R. The proarrhythmic effect of rofecoxib during I/R was not observed in the IPC group. Rofecoxib prolonged the action potential duration (APD) in isolated papillary muscles, which was not seen in the simulated IPC group. Interestingly, while showing hidden cardiotoxicity manifested as a proarrhythmic effect during I/R, rofecoxib decreased the infarct size and increased the survival of adult rat cardiac myocytes that were subjected to simulated I/R injury. This is the first demonstration that rofecoxib increased acute mortality due to its proarrhythmic effect via increased APD during I/R. Rofecoxib did not interfere with the cardiprotective effect of IPC; moreover, IPC was able to protect against rofecoxib-induced hidden cardiotoxicity. These results show that cardiac safety testing with simple preclinical models of I/R injury uncovers hidden cardiotoxicity of rofecoxib and might reveal the hidden cardiotoxicity of other drugs

Törzsfejlesztés optimalizálása antibiotikum és antimikotikum termelő ipari mikroorganizmus produktivitásának fokozására

Az szakdolgozatot ipari titok védi.MSc/MABiotechnológiag

Similar and Distinct Mechanisms in the Protective Processes of Upper and Lower Gastrointestinal Tract

Gastrointestinal (GI) mucosal integrity is based on the balance of aggressive and protective mechanisms. Mucosal damage may occur when the injurious factors become dominant or the mucosal defensive processes are impaired. The main target of the therapy against GI mucosal injury is the reduction of aggressive factors, however, the therapeutic possibilities for stimulation of mucosal defensive processes are rather limited. This overview focuses on the gastric and intestinal mucosal protective mechanisms and discusses the main targets that increase protective processes and increase the mucosal resistance to injurious stimuli at pre-epithelial, epithelial and sub-epithelial levels

Chronic treatment with rofecoxib but not ischemic preconditioning of the myocardium ameliorates early intestinal damage following cardiac ischemia/reperfusion injury in rats

There is some recent evidence that cardiac ischemia/reperfusion (I/R) injury induces intestinal damage within days, which contributes to adverse cardiovascular outcomes after myocardial infarction. However, it is not clear whether remote gut injury has any detectable early signs, and whether different interventions aiming to reduce cardiac damage are also effective at protecting the intestine. Previously, we found that chronic treatment with rofecoxib, a selective inhibitor of cyclooxygenase-2 (COX-2), limited myocardial infarct size to a comparable extent as cardiac ischemic preconditioning (IPC) in rats subjected to 30-min coronary artery occlusion and 120-min reperfusion. In the present study, we aimed to analyse the early intestinal alterations caused by cardiac I/R injury, with or without the above-mentioned infart size-limiting interventions. We found that cardiac I/R injury induced histological changes in the small intestine within 2 hours, which were accompanied by elevated tissue level of COX-2 and showed positive correlation with the activity of matrix metalloproteinase-2 (MMP-2), but not of MMP-9 in the plasma. All these changes were prevented by rofecoxib treatment. By contrast, cardiac IPC failed to reduce intestinal injury and plasma MMP-2 activity, although it prevented the transient reduction in jejunal blood flow in response to cardiac I/R. Our results demonstrate for the first time that rapid development of intestinal damage follows cardiac I/R, and that two similarly effective infarct size-limiting interventions, rofecoxib treatment and cardiac IPC, have different impacts on cardiac I/R-induced gut injury. Furthermore, intestinal damage correlates with plasma MMP-2 activity, which may be a biomarker for its early diagnosis

14-O-Methylmorphine: A Novel Selective Mu-Opioid Receptor Agonist with High Efficacy and Affinity.

14-O-methyl (14-O-Me) group in morphine-6-O-sulfate (M6SU) or oxymorphone has been reported to be essential for enhanced affinity, potency and antinociceptive effect of these opioids. Herein we report on the pharmacological properties (potency, affinity and efficacy) of the new compound, 14-O-methylmorphine (14-O-MeM) in in vitro. Additionally, we also investigated the antinociceptive effect of the novel compound, as well as its inhibitory action on gastrointestinal transit in in vivo. The potency and efficacy of test compound were measured by [35S]GTPgammaS binding, isolated mouse vas deferens (MVD) and rat vas deferens (RVD) assays. The affinity of 14-O-MeM for opioid receptors was assessed by radioligand binding and MVD assays. The antinociceptive and gastrointestinal effects of the novel compound were evaluated in the rat tail-flick test and charcoal meal test, respectively. Morphine, DAMGO, Ile5,6 deltorphin II, deltorphin II and U-69593 were used as reference compounds. 14-O-MeM showed higher efficacy (Emax) and potency (EC50) than morphine in MVD, RVD or [35S]GTPgammaS binding. In addition, 14-O-MeM compared to morphine showed higher affinity for mu-opioid receptor (MOR). In vivo, in rat tail-flick test 14-O-MeM proved to be stronger antinociceptive agent than morphine after peripheral or central administration. Additionally, both compounds inhibited the gastrointestinal peristalsis. However, when the antinociceptive and antitransit doses for each test compound are compared, 14-O-MeM proved to have slightly more favorable pharmacological profile. Our results affirm that 14-O-MeM, an opioid of high efficacy and affinity for MOR can be considered as a novel analgesic agent of potential clinical value

A comprehensive time course and correlation analysis of indomethacin-induced inflammation, bile acid alterations and dysbiosis in the rat small intestine

It has been proposed that changes in microbiota due to nonsteroidal anti-inflammatory drugs (NSAIDs) alter the composition of bile, and elevation of hydrophobic secondary bile acids contributes to small intestinal damage. However, little is known about the effect of NSAIDs on small intestinal bile acids, and whether bile alterations correlate with mucosal injury and dysbiosis. Here we determined the ileal bile acid metabolome and microbiota 24, 48 and 72 h after indomethacin treatment, and their correlation with each other and with tissue damage in rats. In parallel with the development of inflammation, indomethacin increased the ileal proportion of glycine and taurine conjugated bile acids, but not bile hydrophobicity. Firmicutes decreased with time, whereas Gammaproteobacteria increased first, but declined later and were partially replaced by Bilophila, Bacteroides and Fusobacterium. Mucosal injury correlated negatively with unconjugated bile acids and Gram-positive bacteria, and positively with taurine conjugates and some Gram-negative taxa. Strong positive correlation was found between Lactobacillaceae, Ruminococcaceae, Clostridiaceae and unconjugated bile acids. Indomethacin-induced dysbiosis was not likely due to direct antibacterial effects or alterations in luminal pH. Here we provide the first detailed characterization of indomethacin-induced time-dependent alterations in small intestinal bile acid composition, and their associations with mucosal injury and dysbiosis. Our results suggest that increased bile hydrophobicity is not likely to contribute to indomethacin-induced small intestinal damage

The Peripheral Versus Central Antinociception of a Novel Opioid Agonist: Acute Inflammatory Pain in Rats.

Opioid analgesics devoid of central side effects are unmet medical need in the treatment of acute pain (e.g. post-operative pain). Recently, we have reported on 14-O-methylmorphine-6-O-sulfate (14-O-MeM6SU), a novel opioid agonist of high efficacy producing peripheral antinociception in subchronic inflammatory pain in certain doses. The present study focused on the antinociceptive effect of 14-O-MeM6SU compared to morphine in formalin test of an early/acute (Phase I) and late/tonic (Phase II) pain phases. Subcutaneous 14-O-MeM6SU (253-1012 nmol/kg) and morphine (3884-31075 nmol/kg) dose dependently reduced the pain behaviors of both phases. Co-administered naloxone methiodide (NAL-M), a peripherally acting opioid antagonist, abolished the antinociceptive effect of 506 nmol/kg 14-O-MeM6SU. On the other hand, the effects of 14-O-MeM6SU (1012 nmol/kg) and morphine (15538 nmol/kg) were only partially affected by NAL-M, indicating the contribution of CNS to antinociception. Locally injected test compounds into formalin treated paws caused antinociception in both phases. Locally effective doses of test compounds were also injected into contralateral paws. Morphine showed effects in both phases, 14-O-MeM6SU in certain doses failed to produce antinociception in either phase. A NAL-M reversible systemic dose of 14-O-MeM6SU and the lowest systemic effective dose of morphine were evaluated for their sedative effects following isoflurane-induced sleeping (righting reflex). In contrast to morphine, 14-O-MeM6SU in certain antinociceptive doses showed no impact on sleeping time. These data highlight that high efficacy opioids of limited CNS penetration in certain doses mitigate somatic and inflammatory pain by targeting MOR at the periphery