Simplicity within complexity: Seasonality and predictability of hospital admissions in the province of Ontario 1988–2001, a population-based analysis

Background  

Seasonality is a common feature of communicable diseases. Less well understood is whether seasonal patterns occur for non-communicable diseases. The overall effect of seasonal fluctuations on hospital admissions has not been systematically evaluated.     

Failure to thrive

Failure to thrive is one of the most common diagnostic problems in pediatrics. The term is applied to describe a still poorly defined entity. We will define failure to thrive, review the frequency of various etiologies, and present a logical approach to this problem.     

The effects of dietary nucleotides on intestinal blood flow in preterm infants

Nucleotides (NT) are reported to affect development of the immune and gastrointestinal systems, and they are currently added to most term infant formulas. In the present study, dietary NT effects on superior mesenteric artery blood flow were investigated. Formula-fed preterm infants were studied once with a 20 kcal/oz. term infant formula containing 80.6 mg/L of NT (NT+), and once with the same formula with no added NT (NT-) (n = 20, gestational age 28.0 +/- 2.2 wk). A reference group of preterm infants fed human milk was also studied (n = 20, gestational age 29.0 +/- 1.6 wk). Superior mesenteric artery blood flow velocities (BFV) were measured by Doppler ultrasound 15 min before and 30, 60, and 90 min after the start of the feed. BFV rose in all infants from baseline to 30 min after feed initiation, and progressively declined thereafter in infants fed NT- or human milk. However, NT+ feedings were associated with a minimal change in BFV between 60 and 90 min. As a result, the difference in blood flow velocities between baseline and 90 min was significantly greater with the NT+ versus the NT- feedings for the mean, peak systolic, and end diastolic velocities (p = 0.03, 0.05, and 0.03, respectively). BFV after the NT- and human milk feedings were similar. These data suggest that orally administered NT are associated with effects on the intestinal vasculature.     

Obesity in children

The alarming increase in obesity in children has become a major health problem in the increased incidence of type 2 diabetes as well as other complications including cardiovascular diseases, hepatic disorders, skeletal abnormalities, malignancies and in particular psychological disorders. Mechanisms of appetite and energy metabolism are mediated through hormones leptin and ghrelin, and neuropeptide-Y neurons as well as genetic factors. Control of obesity is largely through appetite control and physical exercise.     

Discrimination of normal and abnormal prothrombin and protein C in plasma using a calcium ion-inhibited monoclonal antibody to a common epitope on several vitamin K-dependent proteins

Vitamin K deficiency or administration of vitamin K antagonists results in the biosynthesis of abnormal des-gamma-carboxy forms of the vitamin K-dependent proteins. Monoclonal antibody H-11 binds several vitamin K- dependent proteins at a determinant that includes the first two residues of gamma-carboxyglutamic acid. Antibody H-11 binds fully carboxylated prothrombin and protein C in the presence of EDTA but binding is inhibited by the divalent metal ions, calcium, magnesium, and manganese. By contrast, des-gamma-carboxy prothrombin and protein C bind antibody H-11 the same in the presence of EDTA or calcium ion. Antibody H-11 thus appears to bind a conserved antigenic site containing gamma-carboxyglutamic acid that in the presence of divalent metal ion undergoes a conformational transition. This ability of antibody H-11 to bind des-gamma-carboxy prothrombin and protein C in the presence of calcium ion allowed the development of an immunoassay for these proteins in plasma. Prothrombin and protein C from stably anticoagulated individuals receiving warfarin were characterized by their ability to bind antibody H-11 in the presence of calcium ion. Binding of prothrombin and protein C to antibody H-11 in the presence of calcium correlated temporally with warfarin administration. The inability of calcium ion to inhibit binding of antibody H-11 to abnormal prothrombin and protein C in plasma suggests that the circulating forms of both proteins following warfarin administration cannot undergo the metal ion-dependent conformational transition that includes sequence residues 1 through 12.