Takahiro Sumiya

Large scale deletions in the Saccharomyces cerevisiae genome create strains with altered regulation of carbon metabolism

Saccharomyces cerevisiae, for centuries the yeast that has been the workhorse for the fermentative production of ethanol, is now also a model system for biological research. The recent development of chromosome-splitting techniques has enabled the manipulation of the yeast genome on a large scale, and this has allowed us to explore questions with both biological and industrial relevance, the number of genes required for growth and the genome organization responsible for the ethanol production. To approach these questions, we successively deleted portions of the yeast genome and constructed a mutant that had lost about 5% of the genome and that gave an increased yield of ethanol and glycerol while showing levels of resistance to various stresses nearly equivalent to those of the parental strain. Further systematic deletion could lead to the formation of a eukaryotic cell with a minimum set of genes exhibiting appropriately altered regulation for enhanced metabolite production.

Relationship between adult stature and timing of the pubertal growth spurt

Various literature report that little or no correlation exists between adult stature (AS) and the timing of the pubertal growth spurt in stature. No direct linear relationship between AS and age at peak height velocity (PHV) was evident in the Hiroshima Growth Study sample. However, the partial correlation between AS and age at PHV was negative when stature at PHV was controlled. That is, AS and age at PHV negatively correlate with each other so that the older the age at PHV, the lower the AS when stature at PHV is statistically controlled. This is clearly shown by the scatter diagrams of AS and age at PHV. There is a similar relationship between AS and age at takeoff (or age at minimum height velocity). The stature increment during adolescence negatively correlates with age at PHV, and the stature increment highly correlates with length of adolescence.

Influence of Pneumococcal Conjugate Vaccine on Acute Otitis Media with Severe Middle Ear Inflammation: A Retrospective Multicenter Study

The Japanese guidelines for acute otitis media in children recommend classifying acute otitis media by age, manifestations and local findings, and also recommend myringotomy for moderate-grade cases with severe local findings, severe-grade cases, and treatment-resistant cases. The heptavalent pneumococcal conjugate vaccine was released in Japan in February 2010. In Hiroshima City, public funding allowing free inoculation with this vaccine was initiated from January 2011, and the number of vaccinated individuals has since increased dramatically. This study investigated changes in the number of myringotomies performed to treat acute otitis media during the 5-year period from January 2008 to December 2012 at two hospitals and five clinics in the Asa Area of Hiroshima City, Japan. A total of 3,165 myringotomies for acute otitis media were performed. The rate of procedures per child-year performed in <5-year-old children decreased by 29.1% in 2011 and by 25.2% in 2012 compared to the mean rate performed in the 3 years prior to the introduction of public funding. A total of 895 myringotomies were performed for 1-year-old infants. The rate of myringotomies per child-year performed for acute otitis media in 1-year-old infants decreased significantly in the 2 years after the introduction of public funding for heptavalent pneumococcal conjugate vaccine compared to all years before introduction (p<0.000001). Our results suggest a benefit of heptavalent pneumococcal conjugate vaccine for acute otitis media in reducing the financial burden of myringotomy. In addition, this vaccine may help prevent acute otitis media with severe middle ear inflammation in 1-year-old infants.

Influence of pneumococcal conjugate vaccines on acute otitis media in Japan

OBJECTIVE This study investigated: (i) changes in the incidence of acute otitis media (AOM) following introduction of public funding for free inoculation with 7- and 13-valent pneumococcal conjugate vaccines (PCV7 and PCV13, respectively) and (ii) changes in the rate of myringotomies for AOM (MyfA) in children 1year following the publication of the first edition of the clinical practice guidelines for the diagnosis and management of AOM in children in Japan. METHODS PCV7 was launched on the Japanese market in 2010 and gained public funding in 2011. PCV7 was replaced with PCV13 in November 2013. Using the Japan Medical Data Center Claims Database, an 11-year study conducted between January 2005 and December 2015 investigated the decline in the incidence of visits to medical institutions (VtMI) due to all-cause AOM in children <15years. The rate of MyfA from January 2007 to December 2015was also investigated and changes before and after introduction of public funding for PCV7 (pfPCV7) and PCV13 (pfPCV13) for children were examined. Statistical data for the age group between 10 years and <15years served as the control. An analysis was conducted to examine changes for each age group, from infants that had received PCVs to children <5years. Statistical analysis was performed using the chi-square test and Ryans multiple comparison tests. Ryans multiple comparison tests were applied at a 5% level of significance. Due to significant changes in the guidelines on the indications for myringotomy introduced in 2013, statistical analysis of the rate of MyfA was limited to the pre- and post-PCV7 period. RESULTS After introduction of pfPCV7 and pfPCV13, no significant suppression of the incidence of VtMI was observed in any age group. There was a gradual decline in the rate of MyfA after 2011. Compared to the control group, significant differences in all age groups from infants to children <5years were observed (p<0.009, chi-square test). Within 2 years after the introduction of PCV7, a significant decline in the rate of MyfA was observed in 1- and 5-year-olds using Ryans multiple comparison tests at a 5% level of significance. CONCLUSION The preventative effect of PCVs on AOM was not established in this study. There was, however, a significant decline in the rate of MyfA among 1- and 5-year-olds. Taking into consideration past studies, PCV7 may play a role in preventing the aggravation of AOM in 1-year-olds. When evaluating the effectiveness of PCVs, measures to evaluate severity may be as important as evaluating disease prevention.

Influence of Pneumococcal Conjugate Vaccine on Otitis Media

The vaccine developed for pneumococcal diseases is a heptavalent conjugate vaccine (PCV 7). This particular vaccine consists of capsular polysaccharides originated from seven different Streptococcus pneumoniae species along with the protein diphtheria crm197 as conjugate antigens. In a month time after inoculation in children this vaccine is able to increase the IgG level sufficiently to combat the pneumococcal infections.