Staphylococcus aureus surface protein SasG contributes to intercellular autoaggregation of Staphylococcus aureus.

Staphylococcus aureus surface protein G (SasG) is one of cell surface proteins with cell-wall sorting motif. The sasG mutant showed significantly reduced cell aggregation and biofilm formation. SasG is comprised of variable A domain and multiple tandem repeats of B domain, native-PAGE and in vitro formaldehyde cross-linking experiments revealed that the recombinant protein of the A domain showed homo-oligomerization as an octamer, but B domain did not. This study shows that SasG-A domain contributes to intercellular autoaggregation by homo-oligomerization, and that may facilitate the adherence to host-tissues in the infection of S. aureus.

Rare association of severe hypoplasia of the abdominal aorta with imperforate anus, colonic atresia, and choledochal cyst.

Hypoplasia of the abdominal aorta (HAA) is a rare condition that causes marked hypertension. Although multiple etiologies have been postulated for HAA, congenital structural anomalies are rarely observed except in cases associated with some hereditary syndromes. The authors describe a neonatal case with HAA complicated by multiple anomalies including colonic atresia (CA), imperforate anus, choledochal cyst, facial cleft, and brain defects. This patient showed CA in the descending colon and caliber change in the transverse colon mimicking Hirschsprung disease, both of which were thought to be caused by vascular insult to the mesentery due to HAA. Although multiple surgical corrections were successfully performed, the hypertension was uncontrollable.

Whole genome sequence of Staphylococcus saprophyticus reveals the pathogenesis of uncomplicated urinary tract infection.

Staphylococcus saprophyticus is a uropathogenic Staphylococcus frequently isolated from young female outpatients presenting with uncomplicated urinary tract infections. We sequenced the whole genome of S. saprophyticus type strain ATCC 15305, which harbors a circular chromosome of 2,516,575 bp with 2,446 ORFs and two plasmids. Comparative genomic analyses with the strains of two other species, Staphylococcus aureus and Staphylococcus epidermidis, as well as experimental data, revealed the following characteristics of the S. saprophyticus genome. S. saprophyticus does not possess any virulence factors found in S. aureus, such as coagulase, enterotoxins, exoenzymes, and extracellular matrix-binding proteins, although it does have a remarkable paralog expansion of transport systems related to highly variable ion contents in the urinary environment. A further unique feature is that only a single ORF is predictable as a cell wall-anchored protein, and it shows positive hemagglutination and adherence to human bladder cell associated with initial colonization in the urinary tract. It also shows significantly high urease activity in S. saprophyticus. The uropathogenicity of S. saprophyticus can be attributed to its genome that is needed for its survival in the human urinary tract by means of novel cell wall-anchored adhesin and redundant uro-adaptive transport systems, together with urease.

Placental vascular compromise in jejunoileal atresia.

BACKGROUND/PURPOSE: The mechanisms of intrauterine vascular disruptions that result in the development of jejunoileal atresia (JIA) are not fully understood. Monochorionic twinning with fetal death of a cotwin is known to be correlated with the development of JIA in the survivor through placental communication. The aim of this study was to evaluate whether other placental vascular compromises might contribute to the development of JIA. METHODS: Forty-five newborns (23 boys and 22 girls) who were treated for JIA at Tsukuba University Hospital from 1978 to 2003 were reviewed. Placental findings were informative in 23 cases. RESULTS: No or slight abnormality of the placenta was found in 19 cases. Significant placental abnormalities were found in 4 patients who also had a low birth weight. One patient with apple peel atresia (APA) had excessive torsion of the umbilical cord (UC), which was inserted at the margin of the placenta, and there was an adjacent area of infarction. One patent with multiple atresia (MA) was a surviving monochorionic twin with intrauterine fetal death of the other. Another case of MA showed marginal insertion of the UC. Severe placental abnormalities including wide infarction, cyst formation, and marginal insertion of the UC were found in 1 case of MA. These 3 cases of MA were complicated with other anomalies including brain anomaly. CONCLUSIONS: Placental vascular compromises were involved infrequently in JIA but might possibly be responsible for the development of JIA as well as associated anomalies and a low birth weight as chronic insults since an early stage of gestation in some cases.

Aneurysm of the superficial femoral artery in an infant.

An isolated arterial aneurysm in childhood is extremely rare. We report a 1-year-old girl with an aneurysm of the right superficial femoral artery, presenting as an asymptomatic mass of the thigh. The aneurysm involved the whole superficial femoral artery (9 cm in length), and surgical treatment would have required replacement of the affected artery. Conservative treatment was chosen, influenced by the patient's rapid growth at that time. Non-invasive, 3-D contrast-enhanced magnetic resonance angiography (MRA) was useful as an alternative to conventional angiography for detailed evaluation of the femoral arteries, including the aneurysm.