RESUMO
T-cell immunoglobulin and mucin protein 3 (Tim-3), also known as Hepatitis A virus cellular receptor 2, has been discovered to have a negative regulatory effect on murine T-cell responses. Galectin-9 exhibits various biological effects, including cell aggregation, eosinophil chemoattraction, activation, and apoptosis, observed in murine thymocytes, T-cells, and human melanoma cells. Such approach demonstrated that Galectin-9 acts as a binding partner on Tim-3 and mediates the T-cell inhibitory effects. Tl-gal is a homologous protein to galectin-9, isolated from the adult stage of the canine gastrointestinal nematode parasite Toxascaris leonina. However, molecular mechanism between Tim-3 and galectin-9 is still remain unknown. Here, we describe the cryo-electron microscopy and X-ray structures and interactions of the Tim-3 and Tl-gal complex as well as their biochemical and biophysical characterization. In the structure, Ser46 residue of Tl-gal NCRD was bound to Asp25 residue of hTim-3. Compared to our previous study, the binding site of the complex is the same as the sugar binding site (the Ser46 residue) of Tl-gal. In addition, analysis of the complex structure revealed that the four Tl-gal molecules were in an open form packing and one mTim-3 peptide was bound to one Tl-gal molecule. These observations suggest that how Tl-gal binds hTim3 is essential to understanding the molecular mechanism for the Tim-3-galectin 9 interaction that regulates immune responses. This could potentially serve as a therapeutic target for inflammatory diseases.
Assuntos
Receptor Celular 2 do Vírus da Hepatite A , Toxascaris , Adulto , Camundongos , Animais , Humanos , Cães , Toxascaris/química , Toxascaris/metabolismo , Microscopia Crioeletrônica , Galectinas/metabolismo , Imunoglobulinas , MucinasRESUMO
The increasing prevalence of mobility impairments underscores the urgent need for accessible and affordable mobility aids. To overcome the mobility limitations of people with disabilities, there is an increasing need for the development of lightweight and portable powered wheelchairs that can be easily loaded. This study aimed to perform an early health technology assessment and a formative usability evaluation on a modular (detachable) powered wheelchair. It aimed to gauge device satisfaction among users, pinpoint areas for improvement, and detect any unforeseen errors to inform future development. Engaging 16 participants, including powered wheelchair users, healthcare professionals, and caregivers, the research evaluated the wheelchair's functionality in various scenarios, emphasizing safety, effectiveness, and convenience. Statistical analyses of task performance and satisfaction surveys highlighted that, while powered wheelchair users successfully completed tasks focusing on driving and power control, healthcare professionals and caregivers encountered difficulties with the wheelchair's assembly and disassembly. Despite general positivity, the surveys indicated mixed satisfaction levels regarding safety, validity, and convenience, with specific issues related to frame durability, seat comfort, and control mechanisms. These findings suggest that refining the wheelchair's design and addressing user concerns could significantly enhance satisfaction and mobility services. Future efforts will include a thorough review of an advanced prototype and further satisfaction assessments.
We believe that our study makes a significant contribution to the literature by addressing a critical gap in the understanding of user-centric design and usability testing for powered wheelchairs.By emphasizing the importance of early assessments and incorporating user feedback into the development process, our research offers practical insights for creating more accessible and user-friendly mobility solutions.This contribution is particularly relevant in the context of advancing assistive technology and improving the quality of life for individuals with disabilities.