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961.
962.
Pingjuan Fang Xiaoying Wang Lu Zhang Guohua Yuan Zhi Chen Qi Zhang 《Journal of molecular histology》2010,41(4-5):199-203
LIM mineralization protein 1 (LMP-1) is an essential positive regulator of osteoblast differentiation, maturation and bone formation. Our previous investigations on the distribution of LMP-1 in mature human teeth indicated that LMP-1 might play a role in the odontoblast differentiation and dentin matrix mineralization. The aim of the present study was to use immunohistochemistry to determine the expression of LMP-1 during tooth development in mouse molars. In embryonic and postnatal Kunming mice, LMP-1 protein was expressed during molar development, but the expression levels and patterns differed at various developmental stages. At embryonic day 13.5 (E13.5), LMP-1 was found in the enamel organ. At E14.5, LMP-1 was detected in the entire enamel organ and in the underlying mesenchyme. At E16.5, LMP-1 was observed in the inner and outer enamel epithelium and the stratum intermedium. The expression also converged at the cusps in the dental papilla. At E18.5 and postnatal day 2.5 (P2.5), LMP-1 was restricted to the stratum intermedium, in differentiating dental papilla cells at cusps, while it disappeared in terminal differentiated ameloblasts and odontoblasts. At P13.5, no positive staining was detected in the odontoblasts or in the dental pulp cells. Therefore, LMP-1 showed spatiotemporal expression patterns during molar development and might participate in molar crown morphogenesis and odontoblast differentiation at late molar development. 相似文献
963.
Maomao Zeng Yang Xiao Yizeng Liang Bing Wang Xian Chen Dongsheng Cao Hongdong Li Mei Wang Zhiguang Zhou 《Metabolomics : Official journal of the Metabolomic Society》2010,6(2):303-311
In this paper, a new strategy for processing GC/MS based metabolic profiling data via multivariate methods was proposed, which
is applied to a small pilot study of impaired fasting glucose. The data obtained from plasma samples of impaired fasting glucose
patients and healthy controls were first treated by principal component analysis and partial least squares-discriminant analysis
to explore the differences and discriminators of the two groups. Subsequently, correlation analyses were employed to examine
the relationships between blood glucose and the discriminators or their linear combination, thus may be considered as potential
biomarkers of impaired fasting glucose. The results showed that the metabolic patterns of the two groups were different. Furthermore,
eleven metabolites were screened as discriminators. Levels of nine of the eleven discriminators, say lactate, 2-ketoisocaproic
acid, alanine, α-hydroxyisobutyric acid, urea, phosphoric acid, α-glycerophosphoric acid, palmitic acid and stearic acid,
were found to be significantly higher in impaired fasting glucose patients, while 1-monopalmitin and 1-monostearin showed
the opposite trend. Correlation analysis indicated that 2-ketoisocaproic acid, stearic acid were positively, while 1-monopalmitin
and 1-monostearin were negatively correlated with blood glucose. Moreover, blood glucose correlated well with the linear combination
of the eleven discriminators by canonical correlation analysis. The results have demonstrated that 2-ketoisocaproic acid,
stearic acid and the linear combination of the eleven discriminators may be considered as the potential biomarkers of impaired
fasting glucose and the proposed method may be useful in a larger study for exploring the metabolic alterations and biomarker
candidates of diseases. 相似文献
964.
Zhou J Zhang Y Wen X Cao J Li D Lin Q Wang H Liu Z Duan C Wu K Wang C 《Journal of cellular and molecular medicine》2010,14(11):2641-2645
Recently, the presence of telocytes was demonstrated in human and mammalian tissues and organs (digestive and extra-digestive organs, genitourinary organs, heart, placenta, lungs, pleura, striated muscle). Noteworthy, telocytes seem to play a significant role in the normal function and regeneration of myocardium. By cultures of telocytes in two- and three-dimensional environment we aimed to study the typical morphological features as well as functionality of telocytes, which will provide important support to understand their in vivo roles. Neonatal rat cardiomyocytes were isolated and cultured as seeding cells in vitro in two-dimensional environment. Furthermore, engineered myocardium tissue was constructed from isolated cells in three-dimensional collagen/Matrigel scaffolds. The identification of telocytes was performed by using histological and immunohistochemical methods. The results showed that typical telocytes are distributed among cardiomyocytes, connecting them by long telopodes. Telocytes have a typical fusiform cell body with two or three long moniliform telopodes, as main characteristics. The vital methylene blue staining showed the existence of telocytes in primary culture. Immunohistochemistry demonstrated that some c-kit or CD34 immuno-positive cells in engineered heart tissue had the morphology of telocytes, with a typical fusiform cell body and long moniliform telopodes. Also, a significant number of vimentin+ telocytes were present within engineered heart tissue. We suggest that the model of three-dimensional engineered heart tissue could be useful for the ongoing research on the functional relationships of telocytes with cardiomyocytes. Because the heart has the necessary potential of changing the muscle and non-muscle cells during the lifetime, telocytes might play an active role in the heart regeneration process. Moreover, telocytes might be a useful tool for cardiac tissue engineering. 相似文献
965.
Bihao Cao Yaqing Lu Guoju Chen Jianjun Lei 《Plant Cell, Tissue and Organ Culture》2010,103(2):217-226
The translationally controlled tumor protein (TCTP) is an important component of the target of rapamycin (TOR) signaling pathway,
the major regulator of cell growth in animals and fungi. Despite its relevance, knowledge on plant TCTP homologs is still
limited. In the present study, the full-length BoTCTP cDNA was isolated from a cabbage (Brassica oleracea L.) cDNA library. The BoTCTP cDNA encodes a polypeptide of 168 amino acids and shared the highly conserved GTPase binding surface in all of the species
analyzed. Northern blotting analysis showed that BoTCTP was specifically expressed in the root and stem. Furthermore, the expression of BoTCTP could be obviously enhanced by stress stimuli, including high temperature and salt stresses, while no significant changes
in the BoTCTP expression were observed under ABA stress. Functional analysis of BoTCTP was performed by the silencing of BoTCTP using RNA interference (RNAi) and the BoTCTP RNAi plants exhibited reduced vegetative growth rate and decreased tolerance of the cold, high temperature, and salt stresses.
The reported results clearly suggest that the BoTCTP gene is involved in the regulation of both growth and stress response in cabbage. 相似文献
966.
Effect of exogenous spermidine on polyamine metabolism in water hyacinth leaves under mercury stress 总被引:3,自引:0,他引:3
The influence of exogenous spermidine (Spd) on arginine decarboxylase (ADC), ornithine decarboxylase (ODC), polyamine oxidase
(PAO) activities and polyamines (PAs), proline contents in water hyacinth leaves under Mercury (Hg) stress was investigated
after 6 days treatment. The results showed that free putrescine (Put) content increased, the contents of free spermidine (Spd)
and spermine (Spm) and the (Spd + Spm)/Put ratio in water hyacinth leaves decreased significantly with the increase of the
Hg concentrations. Hg stress also disturbed the activities of ADC, ODC and PAO and caused changes on proline content. Compared
to the Hg-treatment only, exogenous Spd (0.1 mM) significantly reduced the accumulation of free Put, increased the contents
of free Spd and Spm and the ratio of (Spd + Spm)/Put in water hyacinth leaves. Furthermore, exogenous Spd enhanced the activities
of ADC, ODC and PAO and significantly increased proline content. The PS-conjugated PAs and PIS-bound PAs changed in the same
trend as free PAs. These results suggest that exogenous Spd can alleviate the metabolic disturbance of polyamines caused by
Hg in water hyacinth leaves. 相似文献
967.
Dong Li Zheng Li Jianwei Yu Nan Cao Ruyin Liu Min Yang 《Applied and environmental microbiology》2010,76(21):7171-7180
The role of bacteria in the occasional emergence of red water, which has been documented worldwide, has yet to be determined. To better understand the mechanisms that drive occurrences of red water, the bacterial community composition and the relative abundance of several functional bacterial groups in a water distribution system of Beijing during a large-scale red water event were determined using several molecular methods. Individual clone libraries of the 16S rRNA gene were constructed for three red water samples and one sample of normal water. Beta-, Alpha-, and Gammaproteobacteria comprised the major bacterial communities in both red water and normal water samples, in agreement with previous reports. A high percentage of red water clones (25.2 to 57.1%) were affiliated with or closely related to a diverse array of iron-oxidizing bacteria, including the neutrophilic microaerobic genera Gallionella and Sideroxydans, the acidophilic species Acidothiobacillus ferrooxidans, and the anaerobic denitrifying Thermomonas bacteria. The genus Gallionella comprised 18.7 to 28.6% of all clones in the three red water libraries. Quantitative real-time PCR analysis showed that the 16S rRNA gene copy concentration of Gallionella spp. was between (4.1 ± 0.9) × 107 (mean ± standard deviation) and (1.6 ± 0.3) × 108 per liter in red water, accounting for 13.1% ± 2.9% to 17.2% ± 3.6% of the total Bacteria spp. in these samples. By comparison, the percentages of Gallionella spp. in the normal water samples were 0.1% or lower (below the limit of detection), suggesting an important role of Gallionella spp. in the formation of red water.On occasion, extensive precipitation of iron oxides in drinking water distribution systems manifests as red water at the tap and results in serious deterioration of water quality, with undesirable esthetic and health effects (18, 40, 46). The abundance of ferrous iron in source water or the acceleration of corrosion of iron pipelines after the loosening of chemical and microbial films from the interior surfaces of distribution systems might be the sources of iron oxides in red water. Switching of water sources has been observed to be associated with red water due to disruption of the delicate chemical equilibrium in water supply systems (18). High concentrations of anions, particularly sulfate ions, have been recognized as a causative agent of red water in many cases, reflected in high values on indices such as the Larson-Skold index (18, 29). Other physicochemical factors, such as insufficient disinfection residue, extended hydraulic retention time, low levels of dissolved oxygen, high temperature, low alkalinity, and high chloride concentration, have also been implicated in the emergence of red water (18, 46).In addition to physicochemical factors, microorganisms may also participate in the unique phenomenon of red water. Drinking water distribution systems are a unique niche for microorganisms, despite oligotrophic conditions and the presence of free or combined chlorine (3, 18). Phylogenetically diverse bacterial groups can inhabit the bulk water or biofilms attached to pipes. Culture-based and independent analyses have revealed that members of the class Proteobacteria, including the Alpha-, Beta-, and Gammaproteobacteria, are typically the most abundant bacterial group in water distribution systems, followed by bacterial phyla such as Actinobacteria, Firmicutes, and Bacteroidetes (13, 38). Bacteria inhabiting distribution systems mainly fill functions of diverse carbon source utilization and nitrification, as well as microbial corrosion (3). Meanwhile, during periods of red water, abundant ferrous iron in the bulk water creates favorable conditions for the growth of bacteria in the distribution systems, as this iron scavenges residual chlorine and serves as an energy source for iron-oxidizing bacteria. Some neutrophilic iron oxidizers, such as Gallionella spp. and Leptothrix ochracea, which have occasionally been observed in association with red water events because of their distinct morphology, can promote the precipitation of iron oxides by converting ferrous iron to ferric iron (9, 46). As very little energy can be generated during the oxidation of ferrous to ferric iron, a large quantity of iron needs to be oxidized to support the growth of lithotrophic iron oxidizers. It has been calculated that the ratio of iron to the weight of bacterial cell material could be up to approximately 450 to 500, assuming that the oxidation of ferrous iron provides the sole energy for the synthesis of cell material (9). Emerson et al. have found that the oxidation rate of ferrous iron could be up to 600 to 960 nmol per h per cm3 of mat material that contained up to 109 bacterial cells, most of which were iron oxidizers like Gallionella spp. and Leptothrix ochracea, and the oxidation rate of ferrous iron by iron oxidizers could be as high as four times that of dissolved oxygen (15). These neutrophilic iron oxidizers have been even utilized to remove iron from groundwater by passage of preaerated water through sand filters during drinking water treatment (24, 36). Thus, iron-oxidizing species might play an important role in red water events. With the exception of specific neutrophilic iron oxidizers (e.g., Gallionella spp. and Leptothrix ochracea), the whole microbial community composition in red water and the presence of potentially functional groups, including neutrophilic iron-oxidizing bacteria in red water, is poorly defined, possibly because the appearance of this unique phenomenon in real distribution systems is so irregular. To better understand the mechanisms that drive the emergence of red water, the bacterial community composition and the relative abundance of several functional bacterial groups in a water distribution system of Beijing during a large-scale red water event were determined using several molecular methods. The results of this comprehensive investigation of the biological component of red water will provide valuable information for those managing red water events in water distribution systems. 相似文献
968.
Shuqing Cao Xiaohui Bian Shaotong Jiang Zhengyi Chen Hongyong Jian Zehua Sun 《Acta Physiologiae Plantarum》2010,32(1):19-25
As sessile organisms, plants usually experience several stresses simultaneously. It was shown that stress cross-tolerance may be induced by different stressors, including biotic factors as well as heavy metal, hypoxia, ultraviolet-B radiation, heat, high salt, drought, and cold stresses. However, it is unclear whether there is a cross-tolerance toward cold and lead (Pb) stresses in Arabidopsis. In this study, we showed that cold pretreatment enhanced Pb(II) resistance in Arabidopsis, as indicated by lower reduction of root length, fresh weight, and chlorophyll content in the cold-treated plants than the control ones. In the cold-treated seedlings, lower Pb contents were detected in roots and shoots in comparison to the control. This was associated, at least in part, with the activation of the expression of AtPDR12 gene, a pump excluding Pb(II) and/or Pb(II)-containing toxic compounds from the cytoplasm to the exterior of the cell. This finding was further supported by genetic evidence showing that cold treatment was unable to enhance resistance of atpdr12 mutant to Pb(II) stress but could enhance Pb(II) resistance of the wild type. In addition, we also found that cold-induced enhanced Pb(II) resistance was glutathione-independent. Taken together, all these results suggest that cold treatment enhanced Pb(II) resistance in Arabidopsis, at least in part, by activating the expression of AtPDR12 gene. 相似文献
969.
Dunwei Ci Dong Jiang Bernd Wollenweber Tingbo Dai Qi Jing Weixing Cao 《Acta Physiologiae Plantarum》2010,32(2):365-373
Seedlings of wheat (Triticum aestivum L.) cultivars Jing 411, Jinmai 30 and Yangmai 10 were exposed to 0, 10, 20, 30, 40 or 50 μM of CdCl2 in a solution culture experiment. The effects of cadmium (Cd) stress on wheat growth, leaf photon energy conversion, gas
exchange, and Cd accumulation in wheat seedlings were investigated. Gas exchange was monitored at 3, 9, 24 days after treatment
(DAT). Growth parameters, chlorophyll content, leaf chlorophyll fluorescence, and Cd concentration in shoot and root were
measured at 24 DAT. Seedling growth, gas exchange, chlorophyll content, chlorophyll fluorescence parameters were generally
depressed by Cd stress, especially under the high Cd concentrations. Cd concentration and accumulation in both shoots and
roots increased with increasing external Cd concentrations. Relationships between corrected parameters of growth, photosynthesis
and fluorescence and corrected Cd concentrations in shoots and roots could be explained by the regression model Y = K/(1 + exp(a + bX)). Jing 411 was found to be Cd tolerant considering parameters of chlorophyll content, photosynthesis and chlorophyll fluorescence
in which less Cd translocation was from roots into shoots. The high Cd concentrations were in shoots and roots in Yangmai
10 which has been found to be a relative Cd tolerant cultivar in terms of most growth parameters. 相似文献
970.
Mesenchymal stem cells derived from human umbilical cord ameliorate ischemia/reperfusion-induced acute renal failure in rats 总被引:1,自引:0,他引:1
Huiling Cao Hui Qian Wenrong Xu Wei Zhu Xu Zhang Yuan Chen Mei Wang Yongming Yan Ying Xie 《Biotechnology letters》2010,32(5):725-732
Mesenchymal stem cells (MSCs) are candidates for cell therapy of kidney diseases. However, the application of MSC derived
from human umbilical cord (UC-MSC) in treating acute renal failure (ARF) has not been reported. UC-MSCs, 106, were transplantated via the left carotid artery into ARF rats which was established by clamping bilateral pedicles for 60 min
and reperfusing. Serum creatinine and urea nitrogen decreased 4.8 times and 3.6 times as well as caspase-3 and IL-1β decreased
5.8 times and 9 times compared to control groups, respectively. The percent of proliferative cell nuclear antigen (PCNA)-positive
cells (53% ± 7.5%) was higher than that in the control groups (17% ± 4.5%). In addition, the transplanted UC-MSCs could reside
in local injury sites, leading to the relief of hyperemia and inflammation, but no obvious transdifferentiation into renal-like
cells. The results lay the foundation for further study on the potential application of UC-MSC in human disease. 相似文献