5\u27-nucleotidase, oxidative stress and antioxidant status in alcohol consumers and cirrhotic patients

Uvod: Cilj istraživanja bio je izmjeriti aktivnost enzima 5\u27-nukleotidaza kod bolesnika s cirozom jetre i osoba koje uzimaju alkohol. U istraživanju se ispitivao i oksidacijski stres, antioksidansi te njihova povezanost s 5\u27-nukleotidazom. Materijali i metode: Istraživanje je provedeno u tri skupine po 25 ispitanika jednake dobi i spola: I. skupina (kontrolni ispitanici), II. skupina (osobe koje uzimaju alkohol, tj. konzumenti alkohola) i III. skupina (bolesnici s cirozom jetre). Uzorci krvi prikupljeni od ispitanika centrifugirani su kako bi se odvojila plazma za analizu 5\u27-nukleotidaze. Odvojene stanice su tri puta isprane 0,9-postotnom hladnom fiziološkom otopinom i upotrebljene za analizu glutationa, malondialdehida i superoksid-dismutaze. Rezultati: Aktivnost 5\u27-nukleotidaze u serumu bila je statistički značajno povišena kod skupine bolesnika s cirozom i skupine konzumenata alkohola. Koncentracije malondialdehida bile su također statistički značajno povišene kod bolesnika s cirozom jetre i konzumenata alkohola. Koncentracije glutationa i superoksid-dismutaze bile su statistički značajno snižene u obje skupine. Zaključak: Iz ovih rezultata može se zaključiti da je aktivnost 5\u27-nukleotidaze u serumu dosljedno viša kod bolesnika s cirozom jetre i osoba koje uzimaju alkohol. Zapažena razlika mogla bi ukazivati na opseg oštećenja jetre, oštećenja hepatobilijarnog sustava i opstrukcije jetre.Background: The present study was undertaken to determine the 5\u27-nucleotidase enzyme activity in liver cirrhotic patients and alcohol consumers. Oxidative stress, antioxidants and their association with 5\u27-nucleotidase were also investigated. Methods: The study included three groups of 25 age and sex matched subjects: group I (control), group II (alcohol consumers) and group III (cirrhotic patients). Blood samples were collected and centrifuged for separation of plasma for analysis of 5\u27-nucleotidase. Separated cells were washed thrice with 0.9% w/v cold normal saline and used for the analysis of glutathione, malondialdehyde and superoxide dismutase. Results: The activity of serum 5\u27-nucleotidase was significantly increased in both cirrhotic patients and alcohol consumers. The levels of malondialdehyde were also significantly increased in both cirrhotic patients and alcohol consumers. The levels of glutathione and superoxide dismutase were significantly decreased in both cirrhotic patients and alcohol consumers. Conclusions: Study results indicated the activity of serum 5\u27-nucleotidase to be consistently higher in cirrhotic patients and alcohol consumers. The difference recorded might be pointing to the extent of liver damage, hepatobiliary damage, and biliary stasis

Effect of Hydrocortisone on Mortality and Organ Support in Patients With Severe COVID-19: The REMAP-CAP COVID-19 Corticosteroid Domain Randomized Clinical Trial.

Importance: Evidence regarding corticosteroid use for severe coronavirus disease 2019 (COVID-19) is limited. Objective: To determine whether hydrocortisone improves outcome for patients with severe COVID-19. Design, Setting, and Participants: An ongoing adaptive platform trial testing multiple interventions within multiple therapeutic domains, for example, antiviral agents, corticosteroids, or immunoglobulin. Between March 9 and June 17, 2020, 614 adult patients with suspected or confirmed COVID-19 were enrolled and randomized within at least 1 domain following admission to an intensive care unit (ICU) for respiratory or cardiovascular organ support at 121 sites in 8 countries. Of these, 403 were randomized to open-label interventions within the corticosteroid domain. The domain was halted after results from another trial were released. Follow-up ended August 12, 2020. Interventions: The corticosteroid domain randomized participants to a fixed 7-day course of intravenous hydrocortisone (50 mg or 100 mg every 6 hours) (n = 143), a shock-dependent course (50 mg every 6 hours when shock was clinically evident) (n = 152), or no hydrocortisone (n = 108). Main Outcomes and Measures: The primary end point was organ support-free days (days alive and free of ICU-based respiratory or cardiovascular support) within 21 days, where patients who died were assigned -1 day. The primary analysis was a bayesian cumulative logistic model that included all patients enrolled with severe COVID-19, adjusting for age, sex, site, region, time, assignment to interventions within other domains, and domain and intervention eligibility. Superiority was defined as the posterior probability of an odds ratio greater than 1 (threshold for trial conclusion of superiority >99%). Results: After excluding 19 participants who withdrew consent, there were 384 patients (mean age, 60 years; 29% female) randomized to the fixed-dose (n = 137), shock-dependent (n = 146), and no (n = 101) hydrocortisone groups; 379 (99%) completed the study and were included in the analysis. The mean age for the 3 groups ranged between 59.5 and 60.4 years; most patients were male (range, 70.6%-71.5%); mean body mass index ranged between 29.7 and 30.9; and patients receiving mechanical ventilation ranged between 50.0% and 63.5%. For the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively, the median organ support-free days were 0 (IQR, -1 to 15), 0 (IQR, -1 to 13), and 0 (-1 to 11) days (composed of 30%, 26%, and 33% mortality rates and 11.5, 9.5, and 6 median organ support-free days among survivors). The median adjusted odds ratio and bayesian probability of superiority were 1.43 (95% credible interval, 0.91-2.27) and 93% for fixed-dose hydrocortisone, respectively, and were 1.22 (95% credible interval, 0.76-1.94) and 80% for shock-dependent hydrocortisone compared with no hydrocortisone. Serious adverse events were reported in 4 (3%), 5 (3%), and 1 (1%) patients in the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively. Conclusions and Relevance: Among patients with severe COVID-19, treatment with a 7-day fixed-dose course of hydrocortisone or shock-dependent dosing of hydrocortisone, compared with no hydrocortisone, resulted in 93% and 80% probabilities of superiority with regard to the odds of improvement in organ support-free days within 21 days. However, the trial was stopped early and no treatment strategy met prespecified criteria for statistical superiority, precluding definitive conclusions. Trial Registration: ClinicalTrials.gov Identifier: NCT02735707

<i>In vitro </i>studies on peroxidative changes leading to hemolysis of erythrocytes infested with malarial parasite <i>Plasmodium vivax</i>

729-730Blood erythrocytes of 25 confirmed malarial patients infested with P. vivax were analyzed for peroxidation and hemolysis and results compared with 10 uninfected normal control samples. Results indicated significant increase in peroxide formation measured as malondialdehyde, both in presence and absence of H2O2, in parasite infested erythrocytes. These changes induced hemolysis of infected erythrocytes which was increased manifold in presence of H2O2 and could probably be the reason for extensive anemia reported in malaria

The USP46 complex deubiquitylates LRP6 to promote Wnt/β-catenin signaling

The relative abundance of Wnt receptors plays a crucial role in controlling Wnt signaling in tissue homeostasis and human disease. While the ubiquitin ligases that ubiquitylate Wnt receptors are well-characterized, the deubiquitylase that reverses these reactions remains unclear. Herein, we identify USP46, UAF1, and WDR20 (USP46 complex) as positive regulators of Wnt signaling in cultured human cells. We find that the USP46 complex is similarly required for Wnt signaling in Xenopus and zebrafish embryos. We demonstrate that Wnt signaling promotes the association between the USP46 complex and cell surface Wnt coreceptor, LRP6. Knockdown of USP46 decreases steady-state levels of LRP6 and increases the level of ubiquitylated LRP6. In contrast, overexpression of the USP46 complex blocks ubiquitylation of LRP6 by the ubiquitin ligases RNF43 and ZNFR3. Size exclusion chromatography studies suggest that the size of the USP46 cytoplasmic complex increases upon Wnt stimulation. Finally, we show that USP46 is essential for Wnt-dependent intestinal organoid viability, likely via its role in LRP6 receptor homeostasis. We propose a model in which the USP46 complex increases the steady-state level of cell surface LRP6 and facilitates the assembly of LRP6 into signalosomes via a pruning mechanism that removes sterically hindering ubiquitin chains