A non-class I MHC intestinal epithelial surface glycoprotein, gp180, binds to CD8

The activation of CD8(+) T cells by normal intestinal epithelial cells in antigen-specific or allogeneic mixed cell culture systems has significant implications for the modulation of mucosal immune responses due to the fact that these T cells appear to have regulatory rather than cytolytic activity. A 180-kDa glycoprotein (gp180) has been identified and shown to be important in CD8(+) T cell activation by intestinal epithelial cells. In this study, we examine, in further detail, the role that the CD8 molecule plays in this interaction. It has been previously shown that monoclonal antibodies against gp180 inhibited the activation of CD8-associated p56(lck) in T cells. Although indirectly suggested by these data, there was no evidence that the activation of this protein tyrosine kinase was a direct result of gp180 interacting with the CD8 molecule. In this study, we document that soluble gp180 is able to bind to CD8-Fc fusion proteins and is absorbed by human CD8 alpha but not CD4 transfected murine T cells and that this interaction is dependent upon carbohydrate on the gp180 molecule. Furthermore, the sites used for binding by gp180 are distinct from those used by the conventional CD8 ligand, class I MHC. Thus, gp180 appears to be a novel CD8 ligand that plays an important role in the activation of CD8-associated kinases and of CD8(+) T cells.     

Comparative responsiveness of Short-Form 12 and Minnesota Living With Heart Failure Questionnaire in patients with heart failure

BACKGROUND: The Short-Form 12 (SF-12) and Living With Heart Failure Questionnaire (LHFQ) are commonly used to measure quality of life (QOL) in heart failure outcomes research. Their comparative responsiveness, however, has not been documented. METHODS AND RESULTS: A prospective cohort study was conducted among patients attending a university-based heart failure clinic between April 1997 and September 1998. All patients received comprehensive heart failure care management. QOL of patients was assessed by the SF-12 and LHFQ at baseline and 3 months. Of 87 patients completing follow-up, the mean change score was 10.1 for the LHFQ and 5.8 for the SF-12 (both Ps < .001). The change scores of the instruments were correlated (r = 0.61; P < .001). The SF-12 had a greater ability than the LHFQ to statistically detect change in physical health but was less sensitive to changes in mental health. The LHFQ performed better than the SF-12 in the ability to distinguish the differences in perceived global health transition. CONCLUSION: The LHFQ is more responsive than the SF-12 to changes in QOL. The SF-12 should not be used alone to measure the changes in QOL of patients with heart failure.     

Coronavirus disease 2019 pandemic,restriction, and orthopedic trauma: Retrospective observational study

In 2019, the Coronavirus disease 2019 (Covid-19) was reported in Wuhan, China. Governments in various countries had taken many safeguards. This study investigated the incidence of orthopedic trauma in a rural region epidemiologically and guided source distribution and medical professionals to sustain healthcare systems.Between December 2019 and August 2020, 1651 patients admitted to orthopedics and traumatology clinics with trauma were evaluated in this study. Patients were grouped into 3 groups: pre-covid, restriction, and permitted groups. Age, sex, and fracture types of patients were recorded.The number of patients in the pre-covid period was 629 (38.1%), those were 334 (20.2%) in the restriction period, and 688 (41.7%) patients were admitted in the permitted period. A total of 1203 (72.9%) patients with upper extremity fractures, 383 (23.2%) patients with lower extremity fractures, and 65 (3.9%) patients with axial skeleton and pelvic ring fractures were included in the study. The lowest rates were found in the restriction period when all fractures were evaluated according to the admission periods. There were significant differences between admission dates and the fractures (P < .001).In this study, a decrease in orthopedic trauma rates was observed by half in the restriction period compared with the other 2 periods. Public health precautions had led to a reduction in the incidence of orthopedic trauma in all age groups.     

Arterial supply to the human anterior cruciate ligament

The arterial supply to the anterior cruciate ligament (ACL) was prepared for study by injecting a fresh cadaver knee with an epoxy lead-oxide solution and subsequently immersing it in 10% formalin for a 2-week period. The vasculature of the ACL was exposed through dissection for examination. A second specimen was prepared similarly and was evaluated by a CAT scan. ACL vascularization arises from the middle genicular artery and vessels of the infrapatella fat pad and adjacent synovium. The artery gives rise to periligamentous vessels which form a web-like network within the synovial membrane. These periligamentous vessels give rise to penetrating branches which transversely cross the ACL and anastomose with a network of longitudinally oriented endoligamentous vessels. Terminal branches of the inferior medial and lateral genicular arteries supply the distal portion of the ACL directly. The extremities of the ACL seem to be better vascularized than the middle part, and the proximal portion seems to have a greater vascular density than the distal portion. The arteries at the ligamentous-osseous junctions of the ACL do not significantly contribute to the ligament's vascularity. Ramifications concerning the ACL's blood supply as it relates to athletic training is also discussed.