Search

Background: To determine the burden of rotavirus disease before the introduction of rotavirus vaccines., Methods: From February 2005 to June 2006, prospective rotavirus surveillance was conducted in Cincinnati, Ohio, and Durham, North Carolina. Children < 5 years of age presenting at hospitals and outpatient clinics with acute gastroenteritis (AGE) of < 72 hours duration were enrolled. Stool samples were first tested for rotavirus by EIA and the VP7 type was determined by RT-polymerase chain reaction for rotavirus-positive samples. Medical costs were obtained from billing or accounting data., Results: A total of 1998 children were enrolled, with a mean age of 16.9 months. Among 1601 (80%) patients with a stool specimen, 44% were rotavirus positive. The rotavirus detection rate was 38% for patients admitted to hospital, 60% for patients requiring a short-stay hospital visit (< 24 hour hospitalization), 49% for emergency department visits, and 37% for outpatient visits. During the rotavirus season, rotavirus accounted for 56% of all AGE cases. Only 11% of rotavirus-positive children were assigned the rotavirus-specific ICD-9-CM code and this proportion varied considerably by clinical setting. The VP7 genotypes identified were G1, 79%; G2, 14%; G3, 5%; G9, 1%; and G12, 1%. For children hospitalized with rotavirus, the estimated median direct cost was $4565, the average length of stay was 1.9 days, and parents lost 3.4 days of work. For short-stay, emergency department, and outpatient visits, the estimated median costs were $3160, $867, and $75, respectively., Conclusions: Before the widespread use of rotavirus vaccines in the United States, rotavirus was prevalent among children treated in hospital-based and outpatient settings and was associated with a substantial proportion of pediatric medical visits for AGE.

Background: This observational study evaluated a modified immunoprophylactic regimen (hepatitis B immune globulin [HBIG]) and a dose of thimerosal-free monovalent hepatitis B (HB) vaccine shortly after birth followed by doses of thimerosal-free bivalent Haemophilus influenzae type b (Hib)-HB vaccine at 2 and 4 months of age, and a booster at 12 months of age) in infants at high risk of hepatitis B virus (HBV) infection (mothers HBeAg+)., Methods: Children >or=6 months of age vaccinated in routine clinical practice were tested twice (>or=6 months apart) for HBV antigens surface antigen (HBsAg) and "e" antigen, and for antibody to HBsAg. Partial nucleotide sequence analysis was performed on HBV DNA isolated from infants identified with a breakthrough chronic HBV infection. A fully sequential statistical design was used to maximize patient safety and study efficiency., Results: Four of 60 children developed chronic HBV infection despite vaccination, but at no point did the cumulative number of cases reach the boundary of statistical significance. Overall, the analysis adjusted for sequential testing yielded an estimated breakthrough rate of 6.7% (90% CI: 2.3%-14.6%). In a subset of uninfected children tested for antibody to HBsAg 1 to 4 months after the second dose of Hib-HB vaccine, 90% (9/10) had >or=10 milli-International Units per milliliter (mIU/mL). The third dose of Hib-HB vaccine induced a secondary increase in the level of antibody; 94.7% (18/19) of a second group developed >or=100 mIU/mL, with a geometric mean concentration of 771 mIU/mL (95% CI: 351.4-1692.1 mIU/mL)., Conclusion: The tested regimen is comparably effective to historical experience with a standard one employing HBIG plus monovalent thimerosal-containing HB vaccine given at 0, 1, and 6 months of age.

Early outgrowth of the vertebrate embryonic limb requires signalling by the apical ectodermal ridge (AER) to the progress zone (PZ), which in response proliferates and lays down the pattern of the presumptive limb in a proximal to distal progression. Signals from the PZ maintain the AER until the anlagen for the distal phalanges have been formed. The semidominant mouse mutant dactylaplasia (Dac) disrupts the maintenance of the AER, leading to truncation of distal structures of the developing footplate, or autopod. Adult Dac homozygotes thus lack hands and feet except for malformed single digits, whereas heterozygotes lack phalanges of the three middle digits. Dac resembles the human autosomal dominant split hand/foot malformation (SHFM) diseases. One of these, SHFM3, maps to chromosome 10q24 (Refs 6,7), which is syntenic to the Dac region on chromosome 19, and may disrupt the orthologue of Dac. We report here the positional cloning of Dac and show that it belongs to the F-box/WD40 gene family, which encodes adapters that target specific proteins for destruction by presenting them to the ubiquitination machinery. In conjuction with recent biochemical studies, this report demonstrates the importance of this gene family in vertebrate embryonic development.

Pudgy (pu) homozygous mice exhibit clear patterning defects at the earliest stages of somitogenesis, resulting in adult mice with severe vertebral and rib deformities. By positional cloning and complementation, we have determined that the pu phenotype is caused by a mutation in the delta-like 3 gene (Dll3), which is homologous to the Notch-ligand Delta in Drosophila. Histological and molecular marker analyses show that the pu mutation disrupts the proper formation of morphological borders in early somite formation and of rostral-caudal compartment boundaries within somites. Viability analysis also indicates an important role in early development. The results point to a key role for a Notch-signalling pathway in the initiation of patterning of vertebrate paraxial mesoderm.

The mouse syndactylism (sm) mutation impairs some of the earliest aspects of limb development and leads to subsequent abnormalities in digit formation. In sm homozygotes, the apical ectodermal ridge (AER) is hyperplastic by embryonic day 10.5, leading to abnormal dorsoventral thickening of the limb bud, subsequent merging of the skeletal condensations that give rise to cartilage and bone in the digits, and eventual fusion of digits. The AER hyperplasia and its effect on early digital patterning distinguish sm from many other syndactylies that result from later failure of cell death in the interdigital areas. Here we use positional cloning to show that the gene mutated in sm mice encodes the putative Notch ligand Serrate. The results provide direct evidence that a Notch signalling pathway is involved in the earliest stages of limb-bud patterning and support the idea that an ancient genetic mechanism underlies both AER formation in vertebrates and wing-margin formation in flies. In addition to cloning the sm gene, we have mapped three modifiers of sm, for which we suggest possible candidate genes.