Transient hypertension and sustained tachycardia in mice housed individually in metabolism cages.

The novel environment of a metabolic cage can be stressful for rodents, but few studies have attempted to quantify this stress-response. Therefore, we determined the effects on mean arterial pressure (MAP) and heart rate (HR), of placing mice of both sexes in metabolism cages for 2 days. After surgical implantation of a carotid artery catheter mice recovered individually in standard cages for 5 days. Mice then spent 2 days in metabolism cages. MAP and HR were monitored in the standard cage on Day 5 and in metabolism cages on Days 6-7. MAP increased by 18+/-3 and 22+/-4 %, while HR increased by 27+/-4 and 27+/-6 %, in males and females, respectively, during the first hours after cage switch. MAP decreased to baseline in the fourth and eighth h following metabolism cage switch in males and females, respectively. However, HR remained significantly elevated in both sexes during the entire two-day period in metabolism cages. Females had lower MAP than males both pre- and post-metabolism cage switch, but there were no sex differences in HR. These results demonstrate sustained changes in cardiovascular function when mice are housed in metabolism cages, which could potentially affect renal function.

Prenatal and newborn screening for hemoglobinopathies.

The hemoglobinopathies encompass a heterogeneous group of disorders associated with mutations in both the alpha-globin and beta-globin genes. Increased immigration of high-risk populations has prompted the implementation of prenatal and newborn screening programs for hemoglobinopathies across Europe and North America. In Canada, the UK, and other European countries, prenatal screening to identify hemoglobinopathy carriers and offer prenatal diagnostic testing to couples at risk is linked to newborn screening, while in the United States, it is still not universally performed. The structure of screening programs, whether prenatal or postnatal, universal or selective, varies greatly among these countries and within the United States. The laboratory methods used to identify hemoglobinopathies are based on the prevalence of hemoglobinopathies within the population and the type of screening performed. Advances in molecular testing have facilitated the diagnosis of complex thalassemias and sickling disorders observed in ethnically diverse populations. This review summarizes the current approaches and methods used for carrier detection, prenatal diagnosis, and newborn screening.

Bone marrow transplantation in sickle cell anemia.

Hematopoietic cell transplantation (HCT) is a treatment with curative potential for sickle cell disease (SCD). The experience of HCT for persons with beta-thalassemia major has been successfully extended to SCD. Currently, the event-free survival rate after allogeneic-matched sibling HCT for SCD is 82%. However, short-term and long-term transplant-related complications remain substantial barriers to HCT, particularly in older patients with life-long complications of SCD. Novel conditioning regimens that minimize transplant-associated toxicity have been developed and show promise for wider application of HCT. Alternative stem cell sources may also expand the availability of HCT for selected patients with SCD.

A day care-based study of the efficacy of Haemophilus b polysaccharide vaccine.

To assess the efficacy of the Haemophilus b polysaccharide vaccine following licensure and to evaluate the risk of Haemophilus influenzae type b (Hib) disease in the week following vaccination, we conducted a day care-based case-control efficacy study using cases of invasive Hib disease ascertained through active surveillance in areas with a total population of 34 million. For each patient 18 to 59 months old, up to three 18- to 59-month-old controls were chosen from the same day care classroom. Using conditional logistic regression, the vaccine efficacy was estimated to be 45% (95% confidence interval = -1% to 70%) and did not change significantly after accounting for potential biases. In addition, three (3%) of 104 patients vs five (2%) of 207 controls were vaccinated within seven days before the patients' dates of admission (odds ratio = 1.8, 95% confidence interval = 0.3 to 10.2), which does not suggest an increased risk of Hib disease in the week following immunization. This study suggests that the efficacy of the currently used HBPV is less than expected from previous studies and points out the usefulness of case-control studies for monitoring vaccine efficacy following licensure.