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91.
Detection of Noroviruses in Tap Water in Japan by Means of a New Method for Concentrating Enteric Viruses in Large Volumes of Freshwater 总被引:2,自引:1,他引:1
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A virus concentration method using a cation-coated filter was developed for large-volume freshwater applications. Poliovirus type 1 (LSc 2ab Sabin strain) inoculated into 40 ml of MilliQ (ultrapure) water was adsorbed effectively to a negatively charged filter (Millipore HA, 0.45-μm pore size) coated with aluminum ions, 99% (range, 81 to 114%) of which were recovered by elution with 1.0 mM NaOH (pH 10.8) following an acid rinse with 0.5 mM H2SO4 (pH 3.0). More than 80% poliovirus recovery yields were obtained from 500-ml, 1,000-ml, and 10-liter MilliQ water samples and from tap water samples. This method, followed by TaqMan PCR detection, was applied to determine the presence of noroviruses in tap water in Tokyo, Japan. In a 14-month survey, 4 (4.1%) and 7 (7.1%) of 98 tap water samples (100 to 532 liters) contained a detectable amount of noroviruses of genotype 1 and genotype 2, respectively. This method was proved to be useful for surveying the occurrence of enteric viruses, including noroviruses, in large volumes of freshwater. 相似文献
92.
Kumemura H Harada M Yanagimoto C Koga H Kawaguchi T Hanada S Taniguchi E Ueno T Sata M 《Biochemical and biophysical research communications》2008,367(1):33-40
Microtubules (MTs) and microfilaments (MFs) are known to modulate mitochondrial morphology, distribution and function. However, little is known evidence about the role of intermediate filaments (IFs) in modulating mitochondria except desmin. To investigate whether or not the IFs regulate mitochondrial morphology, distribution, and function, we manipulated the IFs of cultured epithelial cells to express a mutant keratin 18 (K18). In contrast to the filamentous expression of wild K18, mutant K18 induced aggregation of K8/18, showing no fine IF network in the cells. In mutant K18-transfected cells, the mitochondria were fragmented into small spheroids, although they were observed as mitochondrial fibers in un-transfected or wild K18-transfected cells. Fluorescence recovery after photobleaching of fluorescence-labeled mitochondria was markedly less in the mutant K18-transfected cells, although a significant recovery was confirmed in wild K18-transfected cells. These findings suggest that the IFs are important for the maintenance of normal mitochondrial structures. 相似文献
93.
A ten-year summary of reproductive parameters for ring-tailed lemurs at berenty, madagascar 总被引:2,自引:2,他引:0
Naoki Koyama Masayuki Nakamichi Ryo Oda Naomi Miyamoto Shinichiro Ichino Yukio Takahata 《Primates; journal of primatology》2001,42(1):1-14
From 1989 to 1998, 204 live births were recorded for ring-tailed lemurs (Lemur catta) at Berenty, Madagascar. Excluding unknown birth dates, the peak month of birth was September, with 82.0% (146/178) occurring
during this period. The offspring sex ratio (1∶1.19) was not significantly different from 1∶1, and there was no association
with the mother's age. The first births occurred at the ages of 2 to 4 yr. The annual birth rate was very low at the age of
2 yr (11.1%), but increased thereafter: to 50.0% at the age of 3 yr, and to 75–85% at the age of 4 or more years. Multiple
births were very rare, since only three sets of twins and one set of triplets were recorded. As for the interbirth interval,
a one-year interval was the most common (92.2%). Infant mortality within the first year was 37.7% (77/204). Neonatal mortality
within the first month accounted for 31.2% of all infant dealths. 相似文献
94.
Abundance, isotopic composition and morphological imprints of the planktonic foraminifera Globorotalia scitula (Brady) were closely examined for possible use as a novel reconstruction tool of chemical environments in sub-intermediate depth seawater in the past. Based on the MOCNES plankton tow observation of dwelling depths of G. scitula and the isotopic compositions together with hydrochemistry data, the empirical relations between isotopic disequilibria in carbon (Δδ13C=δ13CG. scitula−δ13CDIC) and oxygen (Δδ18O=δ18OG. scitula−δ18Ow) isotopes in the carbonate tests and the seawater δ18O and δ13C of dissolved inorganic carbon (DIC), respectively, are introduced. The morphological information such as pore density and porosity is also examined for significant relations to carbonate chemistry. Shell porosity is strongly correlated saturation state of calcite. The dissolution of living G. scitula tests may promote the observed isotopic differences as well as the increases in porosity. Δδ18O of G. scitula is found effectively to be linear function of both water temperature and calcite saturation state (Ω), and thereby temperature equation for G. scitula is provided, while Δδ13C of G. scitula is a linear function of only calcite saturation state.The equation was validated by using Globorotalia scitula collected by a sediment trap in intermediate water depths. Satisfactory agreements were found between observed and calculated Δδ18O from the empirical equations based on temperature and hydrochemistry data at sediment trap deployment site, indicating that the equation may be useful in paleo-environmental reconstruction of sub-intermediate water. The sediment trap observation further suggests that the abundance of G. scitula does not necessarily correspond to surface water productivity and to POC flux, but instead, it correlates well with the supply of fine organic matter, which appears to be a result of water convection. Thus, G. scitula may be an unambiguous and excellent paleo-environmental recorder for carbonate chemistry and for fine organic matter transport to the depths, if isotopic and morphological observations are combined. 相似文献
95.
96.
Elise A. Lamont Ping Wang Shinichiro Enomoto Klaudyna Borewicz Ahmed Abdallah Richard E. Isaacson Srinand Sreevatsan 《PloS one》2014,9(12)
Francisella tularensis, a Gram-negative bacterium and causative agent of tularemia, is categorized as a Class A select agent by the Centers for Disease Control and Prevention due to its ease of dissemination and ability to cause disease. Oropharyngeal and gastrointestinal tularemia may occur due to ingestion of contaminated food and water. Despite the concern to public health, little research is focused on F. tularensis detection in food and environmental matrices. Current diagnostics rely on host responses and amplification of F. tularensis genetic elements via Polymerase Chain Reaction; however, both tools are limited by development of an antibody response and limit of detection, respectively. During our investigation to develop an improved culture medium to aid F. tularensis diagnostics, we found enhanced F. tularensis growth using the spent culture filtrate. Addition of the spent culture filtrate allowed for increased detection of F. tularensis in mixed cultures of food and environmental matrices. Ultraperformance liquid chromatography (UPLC)/MS analysis identified several unique chemicals within the spent culture supernatant of which carnosine had a matching m/z ratio. Addition of 0.625 mg/mL of carnosine to conventional F. tularensis medium increased the growth of F. tularensis at low inoculums. In order to further enrich F. tularensis cells, we developed a DNA aptamer cocktail to physically separate F. tularensis from other bacteria present in food and environmental matrices. The combined enrichment steps resulted in a detection range of 1–106 CFU/mL (starting inoculums) in both soil and lettuce backgrounds. We propose that the two-step enrichment process may be utilized for easy field diagnostics and subtyping of suspected F. tularensis contamination as well as a tool to aid in basic research of F. tularensis ecology. 相似文献
97.
Yukiko Hiraiwa Akihiro Morinaka Takayoshi Fukushima Toshiaki Kudo 《Bioorganic & medicinal chemistry letters》2009,19(17):5162-5165
4-Butyl-3-methylphthalic acid was recognized as a metallo-β-lactamase inhibitor. The structure–activity relationship study of substituted phthalic acids afforded 3-phenylphthalic acid derivatives as potent IMP-1 inhibitors. On the other hand, 3-substituted with 4-hydroxyphenyl phthalic acid derivative displayed a potent combination effect with biapenem (BIPM) against Pseudomonas aeruginosa that produce IMP-1. 相似文献
98.
99.
Shinichiro Gondo Shogo Isayama Koichiro Kusunoki 《Biotechnology and bioengineering》1975,17(3):423-431
The effect of internal diffusion on the slope and the intercept of the LineweaverBurk plots for the immobilized enzyme was considered theoretically and it was found that the slope and the intercept are influenced not only by the dimensionless term M but also by the range of the dimensionless bulk substrate concentration ζb. The dependencies of the slope and the intercept on M and on the rate of ζb are shown graphically. Accurate estimations of M and the maximum velocity of the immobilized enzyme give the true, not apparent, Michaelis constant. It is shown that the linear correlations in the Lineweaver-Burk plots do not always coincide with the correlations for the estimation of M and the maximum velocity. It also is shown that large values of M may induce a serious error in the estimation of M with large values of ζb and in an estimation of the maximum velocity with small values of ζb. 相似文献
100.
Plant Molecular Biology - Identification of the subfamily X leucine-rich repeat receptor-like kinases in the recently sequenced moss and hornwort genomes points to their diversification into... 相似文献