122 research outputs found
Self-identity discrepancy theory: Exploring returning South African Cuban-trained medical students sense of belonging
Background: The Nelson Mandela-Fidel Castro Collaboration programme (NMFCMC) between South Africa and Cuba was established in 1996. South African students, undergo five years of medical training in Cuba and finish the final eighteen months of training in South Africa. These students experience academic difficulties on their return.
Methods: All twelve NMFCMC students enrolled at the University of KwaZulu-Natal in 2015 participated in this study. Data were elicited using focus group interviews, narrative interviews, found photovoice and the Collage Life Story Elicitation Technique.
Results: Challenges faced by participants resulted in identity discrepancy, which in turn promoted unfavourable attitudes, affect, psychological and physical behaviours towards participants’ belongingness.
Conclusion: Returning NMFCMC students experienced difficulties in assimilation due to identity discrepancies and frustrated sense of belonging. Focusing on reinforcing positive aspects of identity, and interpersonal relationships through moderating the tendency of local teachers and students to emphasise the “otherness” of the NMFCMC student is crucial
Lipids Regulate Lck Protein Activity through Their Interactions with the Lck Src Homology 2 Domain.
Lymphocyte-specific protein-tyrosine kinase (Lck) plays an essential role in T cell receptor (TCR) signaling and T cell development, but its activation mechanism is not fully understood. To explore the possibility that plasma membrane (PM) lipids control TCR signaling activities of Lck, we measured the membrane binding properties of its regulatory Src homology 2 (SH2) and Src homology 3 domains. The Lck SH2 domain binds anionic PM lipids with high affinity but with low specificity. Electrostatic potential calculation, NMR analysis, and mutational studies identified the lipid-binding site of the Lck SH2 domain that includes surface-exposed basic, aromatic, and hydrophobic residues but not the phospho-Tyr binding pocket. Mutation of lipid binding residues greatly reduced the interaction of Lck with the chain in the activated TCR signaling complex and its overall TCR signaling activities. These results suggest that PM lipids, including phosphatidylinositol 4,5-bisphosphate and phosphatidylinositol 3,4,5-trisphosphate, modulate interaction of Lck with its binding partners in the TCR signaling complex and its TCR signaling activities in a spatiotemporally specific manner via its SH2 domain.1175Ysciescopu
SH2 domains serve as lipid binding modules for pTyr-signaling proteins
The Src-homology 2 (SH2) domain is a protein interaction domain that directs myriad phosphotyrosine (pY)-signaling pathways. Genome-wide screening of human SH2 domains reveals that similar to 90% of SH2 domains bind plasma membrane lipids and many have high phosphoinositide specificity. They bind lipids using surface cationic patches separate from pY-binding pockets, thus binding lipids and the pY motif independently. The patches form grooves for specific lipid headgroup recognition or flat surfaces for non-specific membrane binding and both types of interaction are important for cellular function and regulation of SH2 domain-containing proteins. Cellular studies with ZAP70 showed that multiple lipids bind its C-terminal SH2 domain in a spatiotemporally specific manner and thereby exert exquisite spatiotemporal control over its protein binding and signaling activities in T cells. Collectively, this study reveals how lipids control SH2 domain-mediated cellular protein-protein interaction networks and suggest a new strategy for therapeutic modulation of pY-signaling pathways.112620Ysciescopu
Implementation of Low Cost Automatic Gear Suggestion System
The present automatic transmission is fully mechanically controlled and costs very high. But the proposed gear suggestion mechanism design makes driving much easier and to achieve efficient driving. It is similar to other transmission system on vehicle as it allows an internal combustion engine, best suited to run at high rotational speed to provide torque outputs necessary for vehicular travel. By this system the manual mechanical gear-shifting system will remain unchanged because it suggests the gear change based on increased speed. This article touches on a PIC microcontroller and a Proximity sensor. The main advantage of using mid-range microcontroller is that it is of low-cost and reliable. This technique can also be used to identify the gear position.
DOI: 10.17762/ijritcc2321-8169.16045
South African Paediatric Surgical Outcomes Study : a 14-day prospective, observational cohort study of paediatric surgical patients
BACKGROUND : Children comprise a large proportion of the population in sub-Saharan Africa. The burden of paediatric surgical disease exceeds available resources in Africa, potentially increasing morbidity and mortality. There are few prospective paediatric perioperative outcomes studies, especially in low- and middle-income countries (LMICs).
METHODS : We conducted a 14-day multicentre, prospective, observational cohort study of paediatric patients (aged <16 yrs) undergoing surgery in 43 government-funded hospitals in South Africa. The primary outcome was the incidence of in-hospital postoperative complications.
RESULTS : We recruited 2024 patients at 43 hospitals. The overall incidence of postoperative complications was 9.7% [95% confidence interval (CI): 8.4–11.0]. The most common postoperative complications were infective (7.3%; 95% CI: 6.2–8.4%). In-hospital mortality rate was 1.1% (95% CI: 0.6–1.5), of which nine of the deaths (41%) were in ASA physical status 1 and 2 patients. The preoperative risk factors independently associated with postoperative complications were ASA physcial status, urgency of surgery, severity of surgery, and an infective indication for surgery.
CONCLUSIONS : The risk factors, frequency, and type of complications after paediatric surgery differ between LMICs and high-income countries. The in-hospital mortality is 10 times greater than in high-income countries. These findings should be used to develop strategies to improve paediatric surgical outcomes in LMICs, and support the need for larger prospective, observational paediatric surgical outcomes research in LMICs.
CLINICAL TRIAL REGISTRATION : NCT03367832.Jan Pretorius Research Fund; Discipline of Anaesthesiology and Critical Care, Nelson R Mandela School of Medicine, University of KwaZulu-Natal; Department of Anaesthesia and Perioperative Medicine, Groote Schuur Hospital and University of Cape Town; Department of Anaesthesia, University of the Witwatersrand; and the Paediatric Anaesthesia Community of South Africa (PACSA).https://bjanaesthesia.org2020-02-01gl2019Anaesthesiolog
ChemInform Abstract: MOLECULAR ADDITION COMPOUNDS. 7. SYNTHESIS OF ADDITION COMPOUNDS OF BORON TRIFLUORIDE, BORANE, AND ALANE WITH N,N,N′N′-TETRAMETHYLETHYLENEDIAMINE AND TRIETHYLENEDIAMINE BY PRECIPITATION FROM ETHER SOLVENTS
ChemInform Abstract: Substitution with Retention in Organoboranes and Utilization of the Phenomenon for a General Synthesis of Pure Enantiomers
ChemInform Abstract: IMPROVED PROCEDURES FOR THE SYNTHESIS OF DIISOPINOCAMPHEYLBORANE OF HIGH OPTICAL PURITY
Molecular addition compounds of N,N,N′,N′-tetramethylethylenediamine with boron trifluoride and monoalkylboranes
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