Chronic Helicobacter pylori infection is associated with peripheral arterial disease.

It is reported that Helicobacter pylori infection is associated with coronary atherosclerosis both epidemiologically and pathogenetically, but no conclusions have yet been reached. Therefore, we investigated the relationship between H. pylori infection and peripheral arterial disease (PAD). Sixty-nine patients with PAD attending Harasanshin General Hospital (Fukuoka, Japan) were compared with 143 controls (age-matched asymptomatic outpatients with hyperlipidemia). H. pylori infection was diagnosed by the detection of IgG antibodies, the (13)C-urea breath test, and histological examination. Multiple logistic regression analysis was used to assess the data. The 69 PAD patients and 143 controls were aged from 50 to 92 years. According to the Fontaine classification, 43/69 PAD patients (62.3%) were grade I, 25 (36.2%) were grade II, and 1 (0.14%) was grade III. The prevalence of H. pylori infection was higher in the PAD patients than in the controls (79.7% versus 44.8%; P < 0.01). Stepwise logistic regression analysis revealed that H. pylori infection and hypertension had a significant influence on the occurrence of PAD. Our results suggest that chronic H. pylori infection may be one of the risk factors for PAD.

Intrafamilial transmission of Helicobacter pylori among the population of endemic areas in Japan.

BACKGROUND: Helicobacter pylori (H. pylori) infection is a worldwide phenomenon related to several gastrointestinal diseases. However, because many aspects concerning the route of transmission remain unclear, we performed this epidemiologic study to clarify the route of intrafamilial transmission of H. pylori. MATERIALS AND METHODS: A retrospective study was performed in three widely separate areas in Japan to investigate the prevalence of H. pylori infection. In 1993, 613 residents were tested as were 4136 in 2002, including 1447 family members of 625 families. Antibody to H. pylori (anti-H. pylori) was determined by enzyme-linked immunosorbent assay. RESULTS: In 2002, the age-adjusted anti-H. pylori prevalence in Hoshino Village (67.5%) was significantly higher than in Kasuya Town (55.0%) and in Ishigaki City (54.7%) (p < .0001, p = .0039, respectively). The age-adjusted anti-H. pylori prevalence of Ishigaki City significantly decreased from 1993 (68.4%) to 2002 (52.5%), showing an age cohort effect. However, the prevalence did not significantly differ in children aged 0-6 years of Ishigaki City between 1993 (9.6%) and 2002 (10.3%). A familial analysis in 2002 demonstrated that the prevalence of anti-H. pylori was significantly higher in children with anti-H. pylori-positive (21.6%, 22 of 102) than with -negative mothers (3.2%, 3 of 95) (p < .0001, by Mantel-Haenszel test), whereas there was no significant difference between children with anti-H. pylori-positive and -negative fathers. Moreover, the prevalence was significantly higher in wives with anti-H. pylori-positive (64.0%, 208 of 325) than with -negative husbands (46.5%, 80 of 172) (p = .0071, by Mantel-Haenszel test) and in husbands with anti-H. pylori-positive (72.2%, 208 of 288) than with -negative wives (56.0%, 117 of 209) (p = .0106, by Mantel-Haenszel test). CONCLUSIONS: In the last decade, H. pylori infection decreased in the general population of Japan by improvement of general hygiene conditions, but did not differ in young children, most likely because of mother-to-child transmission.

Structure and implications for the thermal stability of phosphopantetheine adenylyltransferase from Thermus thermophilus.

Phosphopantetheine adenylyltransferase (PPAT) is an essential enzyme in bacteria that catalyzes the rate-limiting step in coenzyme A (CoA) biosynthesis by transferring an adenylyl group from ATP to 4'-phosphopantetheine (Ppant), yielding 3'-dephospho-CoA (dPCoA). The crystal structure of PPAT from Thermus thermophilus HB8 (Tt PPAT) complexed with Ppant has been determined by the molecular-replacement method at 1.5 A resolution. The overall fold of the enzyme is almost the same as that of Escherichia coli PPAT, a hexamer having point group 32. The asymmetric unit of Tt PPAT contains a monomer and the crystallographic triad and dyad coincide with the threefold and twofold axes of the hexamer, respectively. Most of the important atoms surrounding the active site in E. coli PPAT are conserved in Tt PPAT, indicating similarities in their substrate binding and enzymatic reaction. The notable difference between E. coli PPAT and Tt PPAT is the simultaneous substrate recognition by all six subunits of Tt PPAT compared with substrate recognition by only three subunits in E. coli PPAT. Comparative analysis also revealed that the higher stability of Tt PPAT arises from stabilization of each subunit by hydrophobic effects, hydrogen bonds and entropic effects.