Beta-selection: abundance of TCRbeta-/gammadelta- CD44- CD25- (DN4) cells in the foetal thymus

Expression of TCRbeta and pre-TCR signalling are essential for differentiation of CD4- CD8- double negative (DN) thymocytes to the CD4+ CD8+ double-positive (DP) stage. Thymocyte development in adult Rag1, Rag2 or TCRbetadelta-deficient mice is arrested at the DN3 stage leading to the assumption that pre-TCR signalling and beta-selection occur at, and are obligatory for, the transition from DN3 to DN4. We show that the majority of DN3 and DN4 cells that differentiate during early embryogenesis in wild-type mice do not express intracellular (ic) TCRbeta/gammadelta. These foetal icTCRbeta-/gammadelta- DN4 cells were T lineage as determined by expression of Thy1 and icCD3 and TCRbeta DJ rearrangement. In addition, in the foetal Rag1-/- thymus, a normal percentage of DN4 cells were present. In wild-type mice after hydrocortisone-induced synchronisation of differentiation, the majority of DN4 cells that first emerged did not express icTCRbeta/gammadelta, showing that adult thymocytes can also differentiate to the DN4 stage independently of pre-TCR signalling. Pre-TCR signalling induced expansion in the DN4 population, but lack of TCRbeta/gammadelta expression did not immediately induce apoptosis. Our data demonstrate in vivo differentiation from DN3 to DN4 cell in the absence of TCRbeta/gammadelta expression in the foetal thymus, and after hydrocortisone treatment of adult mice.     

Barriers to Surgical Care Among Children in Somaliland: An Application of the Three Delays Framework

World Journal of Surgery - There are complex barriers that increase delays to surgical care in low- and middle-income countries, particularly among the vulnerable population of children....     

Renal Outcomes in Patients with Type 1 Diabetes and Macroalbuminuria

Macroalbuminuria, defined as urine albumin excretion rate (AER)≥300 mg/d, has long been considered a stage of irreversible kidney damage that leads reliably to GFR loss. We examined the long-term renal outcomes of persons with type 1 diabetes who developed incident macroalbuminuria during the Diabetes Control and Complications Trial (DCCT)/Epidemiology of Diabetes Interventions and Complications (EDIC) study. One hundred fifty-nine participants developed incident macroalbuminuria and were subsequently followed for a median duration of 9 years (maximum of 25 years). At the time of macroalbuminuria diagnosis, mean (SD) age was 37 (9) years, mean (SD) duration of diabetes was 17 (5) years, median AER was 524 mg/d, and mean (SD) eGFR was 108 (20) ml/min per 1.73 m². Ten years after macroalbuminuria diagnosis, the cumulative incidence of a sustained reduction in AER to <300 mg/d was 52%, mostly but not entirely under treatment with renin-angiotensin system inhibitors. The cumulative incidence of impaired GFR (sustained eGFR<60 ml/min per 1.73 m²) 10 years after macroalbuminuria diagnosis was 32%, including 16% who developed ESRD. Lower hemoglobin A1c and BP and regression to AER<300 mg/d were associated with reduced risk of developing impaired GFR. In conclusion, people with type 1 diabetes who develop macroalbuminuria are at high risk of progressive kidney disease. However, through at least 10 years of follow-up, AER could often be controlled, and GFR frequently remained in the normal range.Macroalbuminuria, defined as urine albumin excretion rate (AER)≥300 mg/d, has long been considered a stage of irreversible kidney damage that leads reliably to GFR loss.¹ In early published type 1 diabetes cohorts, macroalbuminuria was associated with a 15-year cumulative incidence of ESRD as high as 75%.^2,3 However, contemporary long-term renal outcomes of macroalbuminuria have not been fully characterized.The Diabetes Control and Complications Trial (DCCT) and its observational follow-up, the Epidemiology of Diabetes Interventions and Complications (EDIC) study, present a valuable opportunity to examine macroalbuminuria and its long-term clinical outcomes. In DCCT/EDIC, the onset of macroalbuminuria can be defined with confidence using frequent longitudinal measurements of AER, participants have been followed for up to 25 years after the diagnosis of macroalbuminuria, and outcomes were meticulously recorded using standardized methods. Previous work in this cohort has shown that most cases of impaired GFR are preceded by macroalbuminuria,⁴ which is associated with a 50-fold higher risk of developing impaired GFR (eGFR<60 ml/min per 1.73 m²).⁵ Here, we extend these studies by comprehensively evaluating the long-term renal outcomes of incident macroalbuminuria in the DCCT/EDIC cohort and examining the risk factors for its progression to impaired GFR.     

Timeliness of infant vaccination and factors related with delay in Flanders,Belgium

Achieving high vaccination coverage is a necessary, but not a sufficient indicator of the quality of a vaccination programme, in terms of control and prevention of childhood infectious diseases. For optimal protection of infants, timeliness of vaccination is increasingly recognized as another important target.     

Breastfeeding after maternal immunisation during pregnancy: Providing immunological protection to the newborn: A review

Vaccination during pregnancy results in an augmentation of disease specific maternal antibodies. Immunoglobulin G (IgG) is mainly transferred through the placenta during the third trimester of pregnancy, while secretory Immunoglobulin A (sIgA) is passed through breast milk. At birth, newborns are partially protected against infectious diseases by these antibodies.