Search

Stilbenes contained in various foods are associated with health beneficial effects. In this study six natural and one synthetic stilbene were tested for their potential to regulate the activity of lipoxygenase and cyclooxygenasein vitro. The most potent inhibitor of 5-lipoxygenase was pterostilbene (IC50= 9.32 μM), whereas the strongest inhibitor of cyclooxygenase-1 and cyclooxygenase-2 was pinostilbene (IC50s= 1.90 and 0.35 μM, respectively). Pterostilbene (IC50s= 11.70 and 27.04 μM for cyclooxygenase-1 and cyclooxygenase-2, respectively) and oxyresveratrol (IC50s= 18.49; 2.79 and 14.71 μM for 5-lipoxygenase, cyclooxygenase-1, and cyclooxygenase-2, respectively) were capable to inhibit catalytic activity of all three tested enzymes. Isorhapontigenin (IC50s= 8.81 and 24.00 μM for cyclooxygenase-1 and cyclooxygenase-2, respectively) and rhapontigenin (IC50s= 24.55 and 36.12 μM for cyclooxygenase-1 and cyclooxygenase-2, respectively) were only moderate or weak inhibitors of both cyclooxygenase forms. In summary, these results indicated that besides the known cyclooxygenase inhibitor resveratrol also other natural stilbenes could be potent inhibitors of the arachidonic acid pathway and deserve further attention as compounds with promising health benefits. [ABSTRACT FROM PUBLISHER]

The aim of the present study was to elucidate the effect of the food additivetert-butylhydroquinone (TBHQ), its metabolitetert-butylbenzoquinone (TBQ), the indirect food additive 2,5-di-tert-butylhydroquinone (DTBHQ) and five other structurally related quinones on the enzymatic activity of cyclooxygenase-1 and -2 (COX-1, -2) and 5-lipoxygenase (5-LO). In a study conducted on purified enzymes TBHQ affected neither COX-1 nor COX-2 activity, but inhibited 5-LO in human neutrophils with an IC50of 13.5 µM. In contrast, DTBHQ regulated the activity of 5-LO as well as the activity of COX-2 (IC50= 1.8 and 14.1 for 5-LO and COX-2, respectively). Thein silicostudies on DTBHQ indicated interactions with the catalytic iron of 5-LO and possible hydrogen bond interactions with His367 or His372. These data suggest that TBHQ and DTBHQ influence arachidonic acid (AA) metabolism in biologically relevant concentrationsin vitroand should be further studied for their possible effect on the AA pathwayin vivo. [ABSTRACT FROM PUBLISHER]

The aim of this study was to evaluate in vitro anti-proliferative (tested on MCF-7, MDA-MB-231, and MCF- 10A cell lines) and anti-inflammatory (evaluated as inhibition of prostaglandin E2 synthesis catalyzed by cyclooxygenase-2) effect of various extracts from Vaccinium bracteatum leaves and fruits. The highest anti-proliferative effect possessed leaf dichloromethane extract with IC50 values ranging from 93 to 198 µg/mL. In the case of cyclooxygenase-2 inhibition, n-hexane, dichloromethane, and ethanol fruit extracts showed the best activity with IC50 values = 2.0, 5.4, and 12.7 µg/mL, respectively. These results indicate that V. bracteatum leaves and fruits could be useful source of anti-cancer and anti-inflammatory compounds. [ABSTRACT FROM AUTHOR]

Possible anti-inflammatory effect of carvacrol was evaluated by in vitro cyclooxygenase-2 (COX-2) assay. Carvacrol inhibited production of prostaglandin E2 catalysed by COX-2 with an IC50 value of 0.8 μM what is practically the same concentration as the IC50 obtained for the standard inhibitors indomethacin and NS-398 with values of 0.7 μM and 0.8 μM, respectively. The COX-1 was inhibited approximately at the same rate (IC50 of 0.7 μM for carvacrol), which suggests non-selective inhibition of both enzyme isoforms. The results of the study demonstrate possible anti-inflammatory potential of this compound due to the inhibition of inducible COX-2 isoform. [ABSTRACT FROM AUTHOR]

Abstract: The effect of exposure to 100mg/L zinc oxide (nZnO), fullerene soot (FS) or titanium dioxide (nTiO2) nanoparticles on gene expression in Arabidopsis thaliana roots was studied using microarrays. After 7d, nZnO, FS, or nTiO2 exposure resulted in 660 up- and 826 down-regulated genes, 232 up- and 189 down-regulated genes, and 80 up- and 74 down-regulated genes, respectively (expression difference>2-fold; p[t test]<0.05). The genes induced by nZnO and FS include mainly ontology groups annotated as stress responsive, including both abiotic (oxidative, salt, water deprivation) and biotic (wounding and defense to pathogens) stimuli. The down-regulated genes upon nZnO exposure were involved in cell organization and biogenesis, including translation, nucleosome assembly and microtubule based process. FS largely repressed the transcription of genes involved in electron transport and energy pathways. Only mild changes in gene expression were observed upon nTiO2 exposure, which resulted in up- and down-regulation of genes involved mainly in responses to biotic and abiotic stimuli. The data clearly indicate that the mechanisms of phytotoxicity are highly nanoparticle dependent despite of a limited overlap in gene expression response. [Copyright &y& Elsevier]

The morphology of the vascular supply of peripheral branches of cardiac nerves has not been systematically described until now. The aim of this study was to describe the architectonics of the vasa nervorum of epicardial nerves in porcine hearts by using two injection techniques. Twenty-three hearts from young healthy pigs were used. In 10 hearts India ink solution was injected into the origin of the anterior interventricular branch. In another 10 hearts India ink solution was injected retrogradely through the coronary sinus. The hearts were then analyzed using a magnifying glass and light microscopy. The arterial injection showed the entirety of the rich venous components of the vasa nervorum, which often consisted of paired veins accompanying the epicardial nerves. The thickness of the nerves ranged from 50 to 815 μm. The vasa nervorum drained into larger subepicardial veins. In seven of the hearts prepared with venous injections the vasa nervorum of epicardial nerves were visualized in the same detail as in the arterial preparations and India ink solution filled the right ventricle via the smallest cardiac veins. The histological analysis of these seven hearts showed complete dehiscence and functional insufficiency of small and larger veins valves. In the other three hearts prepared with venous injections the valves were competent, which prevented retrograde filling of larger and smaller veins. The results obtained expand the current knowledge on epicardial nerves vasa nervorum and provide anatomical evidence behind the mechanism of retrograde application of cardioplegic solutions in cardiac surgery., (© 2021 American Association for Anatomy.)

Performance of a two-stage biofiltration system was investigated for removal of styrene-acetone mixtures. High steady-state acetone loadings (above C(in)(Ac) = 0.5 g.m(-3) corresponding to the loadings > 34.5 g.m(-3).h(-1)) resulted in a significant inhibition of the system's performance in both acetone and styrene removal. This inhibition was shown to result from the acetone accumulation within the upstream trickle-bed bioreactor (TBR) circulating mineral medium, which was observed by direct chromatographic measurements. Placing a biofilter (BF) downstream to this TBR overcomes the inhibition as long as the biofilter has a sufficient bed height. A different kind of inhibition of styrene biodegradation was observed within the biofilter at very high acetone loadings (above C(in)(Ac) = 1.1 g.m(-3) or 76 g.m(-3).h(-1) loading). In addition to steady-state measurements, dynamic tests confirmed that the reactor overloading can be readily overcome, once the accumulated acetone in the TBR fluids is degraded. No sizable metabolite accumulation in the medium was observed for either TBR or BF. Analyses of the biodegradation activities of microbial isolates from the biofilm corroborated the trends observed for the two-stage biofiltration system, particularly the occurrence of an inhibition threshold by excess acetone.

Background and Objective: A new "less invasive" technique avoiding thoracic epidural analgesia has be en tested for suitability as a routine procedure for cardiac anesthesia. Early postoperative extubation is an important step in this fasttrack procedure., Materials and Methods: Consecutive patients (n = 547; age, 35-82 years; mean age, 64 year s; male to female ratio, 3.5) underwent general anesthesia with ultra-short-acting opiates and then underwent coronary surgery (n = 465), valve surgery (n = 38), or combined and other procedures (n = 44) a r;. In 51.4% cases, coronary artery bypass grafting was performed off pump. The percentage of patients extubated within 10 minutes after skin closure was the primary end point. In addition, we attempted to identify the limiting factors of the procedure tested., Results and Discussion: Of the 547 patients, 499 (91%) were extubated within 10 minutes after skin closure. Early extubation failed in 48 (9%) of the patients. The mortality rate was 1.5%. One (0.2%) of the patients needed early reintubation because of pneumothorax. Postoperative myocardial ischemia was recorded in 10 (1.8%) of the patients. Ninetysix (17.5%) of the patients were treated pharmacologically for newly developed atrial fibrillation. None of the patients needed hemodialysis. Transient neurological disorders were recorded in 10 (1.8%) of the patients. The early extubation failure group showed statistically significantly higher rates of preoperative lung dysfunction, use of extracorporeal circulation, administration of inotropic drugs in the operating room, and statistically significantly longer duration of surgery., Conclusion: Early extubation proved suitable as a routine procedure for the vast majority of patients. With a good postoperative analgetic protocol, there is no need for thoracic epidural analgesia. Such avoidance of thoracic epidural analgesia is a further step in minimizing invasiveness in cardiac surgery.