Epidemiological and molecular characterization of invasive Streptococcus pneumoniae isolated following introduction of 7-valent conjugate vaccine in Kinki region, Japan, 2008-2013.

Streptococcus pneumoniae is one of the most common bacteria causing community-acquired pneumonia and meningitis. The use of 7-valent pneumococcal conjugate vaccine (PCV7) has reduced the incidence of pneumococcal disease while changing pneumococcal population through herd immunity and non-vaccine pneumococci replacement. This study investigated molecular epidemiologic characteristics of pneumococcal strains in the Kinki region of Japan from 2008 to 2013. A total of 159 invasive pneumococcal isolates were characterized by serotyping, antibiotic susceptibility testing, PCR analysis of penicillin-binding protein genes, multilocus sequence typing (MLST), and pulsed-field gel electrophoresis (PFGE). In adult populations, pediatric PCV7 introduction decreased isolates expressing PCV7 serotypes via herd immunity and increased isolates expressing non-PCV7 serotypes. The rate of penicillin resistance and isolates with alterations in all three pbp genes was higher in PCV7 type isolates than in non-PCV7 type isolates. In MLST analysis, all of serotype 19F isolates were of the same sequence type, ST236, which is the antimicrobial-resistant clone Taiwan19F-14, and the majority of serotypes 23F and 19A isolates were of ST1437 and ST3111 respectively, which are the predominant clones of antimicrobial-resistant pneumococci in Japan. In PFGE profiles, serotype 6B-ST2224, serotype 19F-ST236, serotype 19A-ST3111, and serotype 23F-ST1437 formed six separate clusters composed of genetically identical strains, and genetically identical serotype 22F-ST433 formed two different clusters between the pre- and post-PCV7 period. The results of molecular analysis suggest the spread and persistence of these identical antimicrobial resistant clones in the Kinki region and genetic changes of epidemic clone serotype 22F-ST433 before and after pediatric PCV7 introduction.

[Clinical microbiological investigation of vancomycin intermediate Staphylococcus aureus during glycopeptide therapy].

We isolated three strains of vancomycin intermediate Staphylococcus aureus (VISA) from a blood sample of a patient with infective endocarditis (VISA-1), postoperative pneumonia sputum (VISA-2), and pyogenic spondylitis blood sample (VISA-3). These VISA strains did not carry vanA, vanB, vanC1, or vanC2/C3 genes. Cell wall thickening was observed. VISA-1 and VISA-3 PFGE patterns showed the completely same pattern compared to the PFGE pattern of methicillin-resistant Staphylococcus aureus first isolated from patients 1 and 3. After 10 days on brain heart infusion agar, wall thickening in all three type of VISA was unchanged, but VISA-2 and VISA-3 reversed vancomycin susceptibility. The most suitable use of vancomycin in patients with MRSA infection thus appears to be in reducing the opportunity for cell wall thickening.

Effects of osthol on blood pressure and lipid metabolism in stroke-prone spontaneously hypertensive rats.

Osthol, a coumarin compound, was isolated from the dried fruits of Cnidium monnieri (Umbelliferae) and the effect of dietary osthol on hypertension and lipid metabolism was examined in stroke-prone spontaneously hypertensive rats (SHRSP). Six-week-old male SHRSP were fed the experimental diet containing 0.05% osthol by weight for 4 weeks with free access to the diet and water. Elevation of systolic blood pressure was significantly suppressed on and after 3 weeks. In addition, significant decreases in cholesterol and triglyceride contents in the liver were recognized without any significant changes in serum lipids profiles. A comparative study on hepatic mRNA expression indicated that osthol induced a significant increase in 3-hydroxy-3-methylglutaryl coenzymeA (HMG-CoA) reductase mRNA expression, which may lead to decrease in hepatic cholesterol pool through inhibition of the enzyme activity. Moreover, osthol induced a significant increase in acyl-CoA oxidase mRNA expression associated with an increase in carnitine palmitoyl transferase 1a mRNA expression, which suggests the acceleration of beta-oxidation of hepatic fatty acids. This may be responsible, at least in part, for the reduction of hepatic triglyceride content in SHRSP. These beneficial effects of osthol could be useful for both prevention of atherosclerosis and suppression of hepatic lipid accumulation.

Phytosterol additives increase blood pressure and promote stroke onset in salt-loaded stroke-prone spontaneously hypertensive rats.

1. To assess the effect of dietary phytosterol on stroke and the lifespan of salt-loaded stroke-prone spontaneously hypertensive rats (SHRSP), we investigated the effects of the addition of phytosterol to soybean oil (phytosterol content: 0.3%) on stroke onset, lifespan following onset of stroke and overall lifespan compared with canola oil (phytosterol content: 0.9%). 2. Six-week-old male SHRSP were fed a test diet prepared by the addition of canola oil (CA diet), soybean oil (SO diet), soybean oil plus 0.6% phytosterol (SO + 0.06P diet) or soybean oil plus 4.5% phytosterol (SO + 0.45P diet) as a 10% fat source. 3. Systolic blood pressure (SBP) increased in the SO + 0.06P and SO + 0.45P groups compared with the SO group and the increase was dependent on the amount of phytosterol added, indicating that the addition of phytosterol to soybean oil may promote an increase in SBP in salt-loaded SHRSP. 4. The onset of stroke was shortest in the SO + 0.45P group and survival after the onset of stroke was shortest in the CA group. Consequently, the SO + 0.45P and CA groups showed marked lifespan shortening, indicating that a fivefold greater amount of phytosterol was required to produce an effect equivalent to that of canola oil. 5. Investigation of the mRNA expression of ATP-binding cassette (ABC) transporters involved in intestinal phytosterol absorption indicated significant decreases in the intestinal mRNA expression of Abcg5 and Abcg8 in SHRSP and Wistar-Kyoto rats compared with Wistar rats. 6. In conclusion, the addition of phytosterol to soybean oil elevated SBP and promoted the onset of stroke, which may cause a reduction in survival time. However, a fivefold greater amount of phytosterol was required to produce an effect that was equivalent to the survival time-shortening effect of canola oil. The significant decrease in the intestinal mRNA expression of Abcg5 and Abcg8 in SHRSP may be responsible, at least in part, for the unfavourable effects observed following the addition of phytosterol.