Optical Imaging of the Nanoscale Structure and Dynamics of Biological Membranes

Biological membranes serve as the fundamental unit of life, allowing the compartmentalization of cellular contents into subunits with specific functions. The bilayer structure, consisting of lipids, proteins, small molecules, and sugars, also serves many other complex functions in addition to maintaining the relative stability of the inner compartments. Signal transduction, regulation of solute exchange, active transport, and energy transduction through ion gradients all take place at biological membranes, primarily with the assistance of membrane proteins. For these functions, membrane structure is often critical. The fluid-mosaic model introduced by Singer and Nicolson in 1972 evokes the dynamic and fluid nature of biological membranes.(1) According to this model, integral and peripheral proteins are oriented in a viscous phospholipid bilayer. Both proteins and lipids can diffuse laterally through the two-dimensional structure. Modern experimental evidence has shown, however, that the structure of the membrane is considerably more complex; various domains in the biological membranes, such as lipid rafts and confinement regions, form a more complicated molecular organization. The proper organization and dynamics of the membrane components are critical for the function of the entire cell. For example, cell signaling is often initiated at biological membranes and requires receptors to diffuse and assemble into complexes and clusters, and the resulting downstream events have consequences throughout the cell. Revealing the molecular level details of these signaling events is the foundation to understanding numerous unsolved questions regarding cellular life

Coagulation factors and natural anticoagulants as surrogate markers of preeclampsia and its subtypes: A case-control study in a Ghanaian population

Preeclampsia (PE) is associated with endothelial injury and hemostatic abnormalities. However, the diagnostic role of coagulation parameters and natural anticoagulants in predicting PE has not been explored in Ghana. This study assessed plasma levels of these factors as surrogate markers of PE and its subtypes. This case-control study included 90 women with PE (cases) and 90 normotensive pregnant women (controls). Blood samples were drawn for the estimation of complete blood count and coagulation tests. The prothrombin time (PT), activated partial thromboplastin time (APTT), and the calculation of the international normalized ratio (INR) were determined by an ACL elite coagulometer while the levels of protein C (PC), protein S (PS), antithrombin III (ATIII), and D-dimers were also measured using the solid-phase sandwich enzyme-linked immunosorbent assay (ELISA) method. All statistical analyses were performed using the R Language for Statistical Computing. Results showed significantly (p \u3c .05) shortened APTT (28.25 s) and higher D-dimer levels (1219.00 ng/mL) among PE women, as well as low levels of PC (1.02 g/mL), PS (6.58 g/mL), and ATIII (3.99 ng/mL). No significant difference was found in terms of PT and INR. From the receiver operating characteristic analysis, PC, PS, and ATIII could significantly predict PE and its subtypes at certain cutoffs with high accuracies (area under the curve [AUC] ≥ 0.70). Most women with PE are in a hypercoagulable state with lower natural anticoagulants. PC, PS, and ATIII are good predictive and diagnostic markers of PE and its subtypes (early-onset PE [EO-PE] and late-onset PE [LO-PE]) and should be explored in future studies

Corrigendum to "European Society for Vascular Surgery (ESVS) 2022 Clinical Practice Guidelines on the Management of Chronic Venous Disease of the Lower Limbs. [Eur J Vasc Endovasc Surg (2022) 63, 184-267]"

proofepub_ahead_of_prin

Editor's Choice – European Society for Vascular Surgery (ESVS) 2022 Clinical Practice Guidelines on the Management of Chronic Venous Disease of the Lower Limbs

Corrigendum: Volume 64, Issues 2–3, 2022, 284-285Peer reviewe

Direct and residual effects of phosphate fertilizer on maize (Zea mays L) grown on an Ultisol in Kumasi, Ghana

(Ghana Journal of Agricultural Science, 1987-90, 20-23: 93-100