RESUMO
Background: The Sickle Pan-African Research Consortium (SPARCO) and Sickle Africa Data Coordinating Center (SADaCC) were set up with funding from the US National Institute of Health (NIH) for physicians, scientists, patients, support groups, and statisticians to collaborate to reduce the high disease burden and alleviate the impact of Sickle Cell Disease (SCD) in Africa. For 5 years, SPARCO and SADaCC have been collecting basic clinical and demographic data from Nigeria, Tanzania, and Ghana. The resulting database will support analyses to estimate significant clinical events and provide directions for targeting interventions and assessing their impacts. Method: The Nigerian study sited at Centre of Excellence for Sickle Cell Disease Research and Training (CESRTA), University of Abuja, adopted REDCap for online database management. The case report form (CRF) was adapted from 1,400 data elements adopted by SPARCO sites. It captures 215 data elements of interest across sub-sites, i.e., demographic, social, diagnostic, clinical, laboratory, imaging, and others. These were harmonized using the SADaCC data dictionary. REDCap was installed on University of Abuja cloud server at https://www.redcap.uniabuja.edu.ng. Data collected at the sites are sent to CESRTA for collation, cleaning and uploading to the database. Results: 7,767 people living with sickle cell disease were enrolled at 25 health institutions across the six zones in Nigeria with 5,295 having had at least one follow-up visit with their clinical data updated. They range from 44 to 1,180 from 3 centers from South East, 4 from South, 5 from South West, 8 from North Central, 4 in North West and 3 in the North East. North West has registered 1,383 patients, representing 17.8%; North East, 359 (4.6%); North Central, 2,947 (37.9%); South West, 1,609 (20.7%); South, 442 (5.7%) and South East, 1,027 patients (13.2%). Conclusion: The database is being used to support studies including analysis of clinical phenotypes of SCD in Nigeria, and evaluation of Hydroxyurea use in SCD. Reports undergoing review in journals have relied on the ease of data access in REDCap. The database is regularly updated by batch and individual record uploads while we are utilizing REDCap's in-built functions to generate simple statistic.
RESUMO
Membrane-bound transcription factor site-1 protease (S1P) is an emerging clinical target due to its roles in lipogenesis, lysosomal biogenesis, unfolded protein response and viral glycoprotein processing. In this study, homology model of S1P was created in order to understand the structural basis for S1P inhibition by PF429242 using molecular docking, molecular dynamics simulation and in silico kinetics studies. PF429242 was docked (GlideScorePF429242=-5.20 kcal/mol) into the catalytic triad (D218, H249 and S414) and validated (R2=0.5686). The reversible binding kinetic parameter (Koff/Kon) was estimated at=7.28E-03 M with fully bound and apo-states interspersed by 3 transient ligand-bound states with unique binding signatures; water plays a major role in PF429242 dissociation from the catalytic site. Communication between key catalytic triad residues is altered in the presence of PF429242. In apo-S1P state, S414-S307/V216-D218 is the preferred route but in PF429242-bound state, S414-S417/V216-D218 is preferred. Communication between S414 and H249 is also shortened in PF429242 bound state; here, only L410 is required unlike apo-state, which requires P418, V256 and F252. Ligand binding did not alter the communication route between S414 and H249 as both recruited D244 and G220. In conclusion, PF429242 binds tightly but reversible to S1P and the details of this interaction has been presented to guide future efforts at developing novel inhibitors. Site-1-protease; PF429242; Kon/Koff; Network analysis.