N-terminal domain of eotaxin-3 is important for activation of CC chemokine receptor 3

Eotaxin-3 belongs to the CC chemokine family, and specificallyrecognizes CC chemokine receptor (CCR) 3 that is expressed oneosinophils, basophils and helper T type 2 cells. The three-dimensionalstructure of eotaxin-3 determined by nuclear magnetic resonancehas revealed that the N-terminal nine residues preceding thefirst cysteine comprise an unstructured domain, which is alsoobserved in other chemokine molecules. In order to determinethe function of the N-terminal domain of eotaxin-3, we constructedvarious N-terminal-deletion mutants, and then examined theirbinding and chemotactic activities toward eosinophils in vitro.Competitive binding studies showed that the binding affinityof truncated mutant toward CCR3 was almost the same as thatof wild-type eotaxin-3 even though the N-terminal truncationinvolved the first through to the ninth residues. In contrast,the chemotactic activity gradually decreased with extensionof the N-terminal deletion, and when the deletion extended tothe eighth residue, the activity was not detected at all. Thus,the N-terminal nine residues are not critical for binding butthe N-terminal eight residues are essential for activation ofCCR3. The truncated eotaxin-3 proteins lacking the N-terminaleight or nine residues inhibited the chemotactic activity ofchemokines that recognize CCR3. The truncated mutants can possiblybe used for anti-allergic and anti-HIV-1 therapy.     

Incidence and influence of GB virus C and hepatitis C virus infection in patients undergoing bone marrow transplantation

Markers of GB virus C (GBV-C) and hepatitis C virus (HCV) were sought in 80 patients before and after they underwent BMT in a metropolitan hospital in Tokyo between 1990 and 1996. RNA of GBV-C was detected in 14 (18%) patients before BMT. Of the 55 patients who had been transfused, 14 (25%) possessed GBV-C RNA at a frequency significantly higher than in the 25 untransfused patients who were all negative (P < 0.01). HCV RNA was detected in three of the 55 (5%) transfused patients, but in none of the 25 untransfused patients. Sera at 3 months after BMT were available for 57 patients. GBV-C RNA persisted in all 10 patients who were infected before BMT, while it was detected in five of the remaining 47 (11%) patients who were not. However, persistent and/or ongoing GBV-C infection had no appreciable influence on patient morbidity or mortality. Two of the 57 patients were positive for HCV RNA before BMT and this persisted after BMT in both. HCV RNA became positive in eight of the remaining 55 (15%) patients who were negative before BMT. Of the 14 patients who received transfusions screened by the first-generation test at BMT, seven (50%) became positive for HCV RNA, a rate significantly higher than the one of 41 (2%) patients who received transfusions screened by the second-generation test (P < 0.001). These results indicate that BMT patients are at increased risk of GBV-C infection transmitted by transfusions received before and at the time of BMT, and that the risk of HCV infection has decreased after the implementation of the second-generation anti-HCV test.     

Dynamic buckling experiments of fluid-structure-coupled co-axial thin cylinder

The purpose of this paper is to clarify dynamic buckling behaviours such as buckling mode and buckling pressure for thin cylindrical shells immersed in fluid subjected to seismic excitations. For this purpose, dynamic buckling experiments of thin cylindrical shells placed inside a rigid liquid container are carried out using a shaking table. These shells and the container are intended to represent thermal baffles and a main vessel of a fast breeder reactor, respectively. The fluid pressure caused by horizontal excitation induces buckling deformation which involves flower-shaped deformation, which is a type of external pressure buckling. The buckling pressure is measured with various types of the test cylinders under seismic excitations and this pressure is confirmed to agree with static buckling pressure predicted by static buckling analysis. It is also found that sub-harmonic vibration occurs under a certain sinusoidal excitation inducing a sudden increase in response displacement at a lower pressure level than the buckling pressure under seismic excitations. Based on these experiments, it is pointed out that, in seismic design, to prevent the buckling of thermal baffles, static buckling analyses can be used as long as sub-harmonic vibration does not occur.     

Adsorption of Biomineralization Protein Mms6 on Magnetite (Fe3O4) Nanoparticles

Biomineralization is an elaborate process that controls the deposition of inorganic materials in living organisms with the aid of associated proteins. Magnetotactic bacteria mineralize magnetite (Fe₃O₄) nanoparticles with finely tuned morphologies in their cells. Mms6, a magnetosome membrane specific (Mms) protein isolated from the surfaces of bacterial magnetite nanoparticles, plays an important role in regulating the magnetite crystal morphology. Although the binding ability of Mms6 to magnetite nanoparticles has been speculated, the interactions between Mms6 and magnetite crystals have not been elucidated thus far. Here, we show a direct adsorption ability of Mms6 on magnetite nanoparticles in vitro. An adsorption isotherm indicates that Mms6 has a high adsorption affinity (Kd = 9.52 µM) to magnetite nanoparticles. In addition, Mms6 also demonstrated adsorption on other inorganic nanoparticles such as titanium oxide, zinc oxide, and hydroxyapatite. Therefore, Mms6 can potentially be utilized for the bioconjugation of functional proteins to inorganic material surfaces to modulate inorganic nanoparticles for biomedical and medicinal applications.     

Relationship between metabolic hormones and ovulation of dominant follicle during the first follicular wave post-partum in high-producing dairy cows

Recent studies suggest that IGF-I is a crucial regulatory factor in follicular growth during early post-partum period. The aim of the present study was to determine in detail the changing profiles of metabolic and reproductive hormones in relation to ovulation of the dominant follicle (DF) of the first follicular wave post-partum in high-producing dairy cows. Plasma concentrations of related hormones in 22 multiparous Holstein cows were measured from 4 weeks pre-partum to 3 weeks post-partum, and the development of DF was observed with colour Doppler ultrasound. Thirteen cows showed ovulation by 15.2 days post-partum. Anovulatory cows showed higher GH and lower IGF-I levels than those in ovulatory cows during the peri-partum period. Each DF developed similarly, and a clear blood flow in the follicle wall was observed despite ovulation or anovulation. In addition, detailed endocrine profiles were analyzed in 9 out of the 22 cows. Five cows showed an increase in plasma oestradiol-17beta (E2) with follicular growth followed by E2 peak, LH surge and ovulation. In these cows, plasma IGF-I concentrations remained high until 10 days post-partum followed by a gradual decrease. Subsequently, the insulin level increased together with the E2 peak towards ovulation. These profiles were not observed in anovulatory cows. In conclusion, our data strongly support the concept that IGF-I and insulin represent 'metabolic signals' of the resumption of ovarian function post-partum in high-producing dairy cows. Moreover, we provide the first visual evidence that both ovulatory and anovulatory DFs of the first follicular wave post-partum are similarly supplied with active blood flow.     

Effects of blueberry and cranberry consumption on type 2 diabetes glycemic control: A systematic review

The metabolic effects of cranberry and blueberry consumption on glycemic control have been evaluated in vitro and in animal models as well as in human studies, although findings have not been systematically reviewed yet. Therefore, a systematic review was carried out of relevant randomized clinical trials (RCTs) in order to assess the effect of berries (blueberry and cranberry) consumption on type 2 diabetes (T2DM) glycemic control. Some evidences were also discussed on the anti-diabetic mechanisms exerted by berries polyphenols. Studies were identified by searching electronic databases: LILACS, PubMed/MEDLINE, Scopus, The Cochrane Library and Web of Science. Three authors independently searched and extracted RCTs in which the effect of berries (cranberry or blueberry) consumption on T2DM glycemic control was assessed. A total of 7 RCTs, involving 270 adults with type 2 diabetes were included. Despite the heterogeneity of the administration forms (in natura, dried, extract, preparations – juice), dosage, duration of the intervention and type of population of the studies involving these two berries some studies highlight the potential benefit of berries, especially of blueberry, on glucose metabolism in T2DM subjects. Daily cranberry juice (240 mL) consumption for 12 weeks and blueberry extract or powder supplementation (9.1 to 9.8 mg of anthocyanins, respectively) for 8 to 12 weeks showed a beneficial effect on glucose control in T2DM subjects. Those results indicate a promising use of these berries in T2DM management; although more studies are required to better understand the mechanisms involved.     

Vitamin B6 suppresses serine protease inhibitor 3 expression in the colon of rats and in TNF-α-stimulated HT-29 cells

Scope: Previous reports in the areas of animal studies and, recently epidemiology, have linked anti‐tumorigenic and anti‐inflammatory effects to dietary vitamin B6. This study investigated the molecular mechanism of these effects of vitamin B6. Methods and results: DNA microarray analysis was used to obtain information on changes in colon gene expression from vitamin B6 (pyridoxine) repletion in vitamin B6‐deficient rats. Pyridoxine supplementation down‐regulated the inflammatory molecule, serine protease inhibitor clade A member 3 (SPI‐3) mRNA expression in the colon. This study also showed that tumor necrosis factor α (TNF‐α) induced SPI‐3 mRNA expression in HT‐29 human colon cancer cells, and vitamin B6 (pyridoxal hydrochloride) pretreatment of HT‐29 cells inhibited TNF ‐induced mRNA expression of SPI‐3. Vitamin B6 inhibited TNF‐α‐induced NF‐κB activation via suppression of IκBα degradation in HT‐29 cells. HT‐29 cells stably expressing epitope‐tagged ubiquitin were generated and vitamin B6 pretreatment was shown to inhibit ubiquitination of the IkB protein in response to TNF‐α‐i. Conclusion: Vitamin B6 suppressed SPI‐3 expression in the colon of rats and in TNF‐α‐stimulated HT‐29 cells. Further, this study showed a possible role of vitamin B6 in the regulation of protein ubiquitination.     

Analysis of methane production by microorganisms indigenous to a depleted oil reservoir for application in Microbial Enhanced Oil Recovery

We examined methane production by microorganisms collected from a depleted oilfield. Our results indicated that microorganisms indigenous to the petroleum reservoir could effectively utilize yeast extract, suggesting that the indigenous microorganisms and proteinaceous nutrients could be recruitable for Microbially Enhanced Oil Recovery.