RESUMO
Knowledge of childbirth outcomes of Black and Latinx individuals during the coronavirus pandemic is limited. Black/African American and Latinx/Hispanic individuals were matched to non-Hispanic white individuals on socio-demographics. Minority individuals were nearly three times more likely to have clinically significant traumatic stress in response to childbirth and two times more likely to report postpartum depression. Unplanned Cesarean rates were higher and incidences of skin-to-skin and breastfeeding were lower in the minority group. Racial and ethnic maternal disparities exist during COVID-19.
RESUMO
The Na+/H+ antiporter in vacuolar membranes transports Na+ from the cytoplasm to vacuoles using a pH gradient generated by proton pumps, which could reduce Na+ toxicity. It is uncertain that whether the woody plants have the same mechanism. Through differential centrifugation and sucrose density gradient centrifugation, tonoplast vesicles were isolated from Populus tremula calli broken by blender. After establishing pH gradient by V-ATPase, Na+ could dissipate the pH gradient, which indicates that there is Na+/H+ antiporter in the tonoplast vesicles from Populus tremula calli (Km=11.4 mmol/L). Amiloride could inhibit the Na+/H+ antiporter activity. The antiporter could transport Na+ and K+, the affinity for Na+ is higher. Salt stress decreased Km and Vmax.
RESUMO
It is generally believed that sphingomyelin- and cholesterol-enriched microdomains can be isolated as detergent-resistant membranes (DRMs) from plasma membrane and organelle membranes. Here the isolation of microdomains from porcine cardiac sarcoplasmic reticulum (SR) membranes is described. These SR-derived detergent-resistant membranes (SR-DRMs) enriched in sphingomyelin and cholesterol have a low buoyant density. Both ganglioside GM1 and caveolin-3 in the SR, known as a marker protein of caveolae at plasma membrane are present in the SR-DRMs. It was demonstrated that significant amount of SERCAs together with caveolin-3 associates with SR-DRMs, and are fully functional. The results suggested that SR membranes like other biomembranes,such as the plasma membrane, contained microdomains.
RESUMO
Four methods were compared to purify Fo from porcine h ear t mitochondria. The best results were obtained by the following method: after re moving F1-ATPase with NaBr incubation from submitochondrial FoF1-ATPase, Fo was solubilized with CHAPS and purified by sucrose density gradient centri fugation. SDS-PAGE with silver staining showed about 85% purity of the isolated Fo and 9 different subunits including b, OSCP, d, a, e, F6, IF1, A6L and c. The purified Fo was then incorporated into asolectin liposomes, the reconst ituted Fo showed higher H+ translocation activity and after Fo was reconst ituted with F1-ATPase, the resulted FoF1-ATPase complex exhibited high A TP hydrolysis activity and high sensitivity to oligomycin. The results provide e vidence for successful purification, reconstitution of Fo with high H+ trans location activity and its relationship with phospholipids.
RESUMO
Synaptosomes were isolated from pig brain by homogenization, differential centrifugation and sucrose gradient centrifugation. After synaptosome lysis in hypoosmotic buffer, the plasma membrane vesicles were collected. Following the solubilization of plasma membrane vesicles in Triton X-100, the solubilized protein was applied to calmodulin affinity chromatography colurnn, and the delipidated plasma membrane Ca2 + -ATPase was purified to nearly homogeneity. The novel feature of this purification is the use of large affinity column and heavy washing to facilitate the purified Ca2+ -ATPase with higher activity and protein yield. The specific activity of the purified Ca2+ -ATPase was recovered to a maximum of 3.32 μmol· mg-1· min-1 after incubation with asolectin. Silver staining of SDS-PAGE revealed a single protein band around Mr 140 000, showing the purity was over 90 %. Different Ca2 + concentrations dramatically affect the specific activity of Ca2 + -ATPase.