Geographical Distribution of Adolescent Body Height with Respect to Effective Day Length in Japan: An Ecological Analysis

The height of Japanese youth raised in the northern region tends to be greater than that of youth raised in the southern region; therefore, a geographical gradient in youth body height exists. Although this gradient has existed for about 100 years, the reasons for it remain unclear. Consideration of the nutritional improvement, economic growth, and intense migration that has occurred in this period indicates that it is probably the result of environmental rather than nutritional or genetic factors. To identify possible environmental factors, ecological analysis of prefecture-level data on the body size of 8- to 17-year-old youth averaged over a 13-year period (1996 to 2008) and Japanese mesh climatic data on the climatic variables of temperature, solar radiation, and effective day length (duration of photoperiod exceeding the threshold of light intensity) was performed. The geographical distribution of the standardized height of Japanese adolescents was found to be inversely correlated to a great extent with the distribution of effective day length at a light intensity greater than 4000 lx. The results of multiple regression analysis of effective day length, temperature, and weight (as an index of food intake) indicated that a combination of effective day length and weight was statistically significant as predictors of height in early adolescence; however, only effective day length was statistically significant as a predictor of height in late adolescence. Day length may affect height by affecting the secretion of melatonin, a hormone that inhibits sexual and skeletal maturation, which in turn induces increases in height. By affecting melatonin production, regional differences in the duration of the photoperiod may lead to regional differences in height. Exposure to light intensity greater than 4000 lx appears to be the threshold at which light intensity begins to affect the melatonin secretion of humans who spend much of their time indoors.     

Optimal production of glutathione by controlling the specific growth rate of yeast in fed-batch culture

The optimal of the specific growth rate was obtained with simple mathematical model in a yeast fed-batch cultures. The model was based on the mass balance around the fed-batch system and the relationship between the specific growth rate, mu, and the specific production rate of glutathione, rho(G). The optimal profile of mu was calculated as a bang-bang type, That is mu, should start from the maximum value, mu(max) and should be kept at mu(max); then mu should be switched to mu(c), which gives a maximum value of rho(G). It was proven from the maximum principle that switching was needed only once, with the switching time from mu(max) to mu(c) depending on the final required glutathione content. Finally, this ideal profile of mu for the maximum production of glutathione was realized by manipulating the substrates feed rate in the fed-batch culture. Using the extended Kalman filter and a programmed-controller/feedback-compensator (PF) system, mu could be controlled at the optimal profile obtained. As a result, the maximum production of glutathione was accomplished fairly successfully. However, further improvement in the controller performance for mu is desired. The control strategy employed here can be applied to other batch reaction processes.     

Microbial communities associated with acetate-rich gas-petroleum reservoir surface facilities

We evaluated the microbial communities in acetate-rich production waters from separators of a high-temperature gas-petroleum reservoir in Higashi-Niigata, Japan. Bacterial and archaeal 16S rRNA gene libraries constructed from these waters were dominated by Acetobacterium-, Methanofollis-, and Methanosarcina-related sequences. The libraries constructed from enrichment cultures of the production waters were dominated by sequences related to the Acetobacterium- and Methanofollis-related sequences.     

SSA/Ro52 autoantigen interacts with Dcp2 to enhance its decapping activity

We identified human decapping enzyme 2 (hDCP2) as a binding protein with Ro52, being colocalized in processing bodies (p-bodies). We also showed that the N-terminus and C-terminus of Ro52 bound to hDCP2. Moreover, Ro52 enhanced decapping activity of hDCP2 in a dose-dependent manner. Our data support the novel notion of the association between Ro52 with hDCP2 protein in cytoplasmic p-bodies, playing a role in mRNA metabolism in response to cellular stimulation.     

Dynamics of hepatitis B virus quasispecies in association with nucleos(t)ide analogue treatment determined by ultra-deep sequencing

Background and Aims

Although the advent of ultra-deep sequencing technology allows for the analysis of heretofore-undetectable minor viral mutants, a limited amount of information is currently available regarding the clinical implications of hepatitis B virus (HBV) genomic heterogeneity.

Methods

To characterize the HBV genetic heterogeneity in association with anti-viral therapy, we performed ultra-deep sequencing of full-genome HBV in the liver and serum of 19 patients with chronic viral infection, including 14 therapy-naïve and 5 nucleos(t)ide analogue(NA)-treated cases.

Results

Most genomic changes observed in viral variants were single base substitutions and were widely distributed throughout the HBV genome. Four of eight (50%) chronic therapy-naïve HBeAg-negative patients showed a relatively low prevalence of the G1896A pre-core (pre-C) mutant in the liver tissues, suggesting that other mutations were involved in their HBeAg seroconversion. Interestingly, liver tissues in 4 of 5 (80%) of the chronic NA-treated anti-HBe-positive cases had extremely low levels of the G1896A pre-C mutant (0.0%, 0.0%, 0.1%, and 1.1%), suggesting the high sensitivity of the G1896A pre-C mutant to NA. Moreover, various abundances of clones resistant to NA were common in both the liver and serum of treatment-naïve patients, and the proportion of M204VI mutants resistant to lamivudine and entecavir expanded in response to entecavir treatment in the serum of 35.7% (5/14) of patients, suggesting the putative risk of developing drug resistance to NA.

Conclusion

Our findings illustrate the strong advantage of deep sequencing on viral genome as a tool for dissecting the pathophysiology of HBV infection.     

Suppression of matrix metalloproteinase production in nasal fibroblasts by tranilast, an antiallergic agent, in vitro

Allergic rhinitis is an inflammatory disease characterized by nasal wall remodeling with intense infiltration of eosinophils and mast cells/basophils. Matrix metalloproteinases (MMPs), MMP-2 and MMP-9, are the major proteolytic enzymes that induce airway remodeling. These enzymes are also important in the migration of inflammatory cells through basement membrane components. We evaluated whether tranilast (TR) could inhibit MMP production from nasal fibroblasts in response to tumor necrosis factor-alpha (TNF-alpha) stimulation in vitro. Nasal fibroblasts (NF) were established from nasal polyp tissues taken from patients with allergic rhinitis. NF (2 x 10(5) cells/mL) were stimulated with TNF-alpha in the presence of various concentrations of TR. After 24 hours, the culture supernatants were obtained and assayed for MMP-2, MMP-9, TIMP-1, and TIMP-2 levels by ELISA. The influence of TR on mRNA expression of MMPs and TIMPs in cells cultured for 12 hours was also evaluated by RT-PCR. TR at more than 5 x 10(-5) M inhibited the production of MMP-2 and MMP-9 from NF in response to TNF-alpha stimulation, whereas TIMP-1 and TIMP-2 production was scarcely affected. TR also inhibited MMP mRNA expression in NF after TNF-alpha stimulation. The present data suggest that the attenuating effect of TR on MMP-2 and MMP-9 production from NF induced by inflammatory stimulation may underlie the therapeutic mode of action of the agent in patients with allergic diseases, including allergic rhinitis.     

Purification and characterization of a novel enzyme, arylalkyl acylamidase, from Pseudomonas putida Sc2.

A novel enzyme, arylalkyl acylamidase, which shows a strict specificity for N-acetyl arylalkylamines, but not acetanilide derivatives, was purified from the culture broth of Pseudomonas putida Sc2. The purified enzyme appeared to be homogeneous, as judged by native and SDS/PAGE. The enzyme has a molecular mass of approximately 150 kDa and consists of four identical subunits. The purified enzyme catalyzed the hydrolysis of N-acetyl-2-phenylethylamine to 2-phenylethylamine and acetic acid at the rate of 6.25 mumol.min-1.mg-1 at 30 degrees C. It also catalyzed the hydrolysis of various N-acetyl arylalkylamines containing a benzene or indole ring, and acetic acid arylalkyl esters. The enzyme did not hydrolyze acetanilide, N-acetyl aliphatic amines, N-acetyl amino acids, N-acetyl amino sugars or acylthiocholine. The apparent Km for N-acetylbenzylamine, N-acetyl-2-phenylethylamine and N-acetyl-3-phenylpropylamine are 41 mM, 0.31 mM and 1.6 mM, respectively. The purified enzyme was sensitive to thiol reagents such as Ag2SO4, HgCl2 and p-chloromercuribenzoic acid, and its activity was enhanced by divalent metal ions such as Zn2+, Mg2+ and Mn2+.     

Antimicrobial susceptibility and genetic relatedness of bovine Stenotrophomonas maltophilia isolates from a mastitis outbreak

Aims: To evaluate the antimicrobial susceptibility and genetic relatedness of 11 Stenotrophomonas maltophilia isolates from an outbreak of bovine clinical mastitis in one herd and two isolates from two separate mastitis cases in two other herds. Methods and Results: Thirteen S. maltophilia isolates were obtained from milk samples from 11 cows from three dairy herds in Japan during 2008. We tested their susceptibility to 14 antimicrobials by broth microdilution and identified their genotypes by enterobacterial repetitive intergenic consensus 2 (ERIC2)‐PCR. Every cow had acute mild mastitis (slightly watery foremilk with flakes) without systemic symptoms and all resolved within 3–5 weeks of diagnosis. Eleven of the 13 isolates derived from nine cows in one herd over a 7‐month period exhibited a closely related ERIC2 type (A). The remaining two isolates derived from two cows from two other herds exhibited two distinct ERIC2 types (B and C). Most of the 13 isolates exhibited susceptibility to trimethoprim‐sulfamethoxazole, chloramphenicol, minocycline and levofloxacin; however, they were resistant to four β‐lactams, kanamycin, gentamicin and oxytetracycline. They were intermediate to enrofloxacin. Conclusions: Eleven closely related S. maltophilia isolates were involved in a herd outbreak of mastitis to some extent. Bovine S. maltophilia isolates exhibited resistance to many classes of antimicrobials. Significance and impact of study: This is a rare report of a herd outbreak of bovine mastitis involving closely related S. maltophilia isolates.