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991.
Hassan Sadri Negar Nowroozi Larki Saeed Kolahian 《Biological trace element research》2017,178(2):246-252
The main objective was to determine the elemental profile of the lung lining fluid of rats which are used as model animals in various experiments. Lung lining fluid elemental constitution obtained after bronchoalveolar lavage fluid (BALF) was analyzed by inductively coupled plasma mass spectrometry (ICP-MS) to determine the biological trace elements along with calcium and magnesium. BALF was collected from healthy rats using a tracheal cannula. However, cells in BALF were counted to monitor any underlying inflammatory lung condition. Cell free BALF samples were processed and analyzed for the elements including magnesium (Mg), calcium (Ca), chromium (Cr), manganese (Mn), iron (Fe), nickel (Ni), copper (Cu), zinc (Zn), selenium (Se), bromine (Br), and iodine (I). In view of this, calcium concentration was the highest (6318.08 ± 3094.3 μg/L) and copper concentration was the lowest (0.89 ± 0.21 μg/L). The detected elements, from high to low concentration, include Ca > Mg > Fe > Br > I > Cr > Ni > Zn > Mn > Se > Cu. Pearson’s correlation analysis revealed no significant correlation between cell count and concentration of any of the element detected in BALF. Correlation analysis also revealed significant positive correlation among Fe, I, Cr, Ni, and Mn. Ca was found to be correlated negatively with Cu and positively with Se. Br and Mg found to be positively correlated with each other. Zn remained the only element that was not found to be correlated with any of the elements in the rat BALF. 相似文献
992.
Wojciech Roczniak Barbara Brodziak-Dopierała Elżbieta Cipora Agata Jakóbik-Kolon Joanna Kluczka Magdalena Babuśka-Roczniak 《Biological trace element research》2017,178(2):201-209
Osteoarthritis causes the degradation of the articular cartilage and periarticular bones. Trace elements influence the growth, development and condition of the bone tissue. Changes to the mineral composition of the bone tissue can cause degenerative changes and fractures. The aim of the research was to determine the content of cadmium (Cd), nickel (Ni), copper (Cu) and zinc (Zn) in the tibia, the femur and the meniscus in men and women who underwent a knee replacement surgery. Samples were collected from 50 patients, including 36 women and 14 men. The determination of trace elements content were performed by ICP-AES method, using Varian 710-ES. Average concentration in the tissues of the knee joint teeth amounted for cadmium 0.015, nickel 0.60, copper 0.89 and zinc 80.81 mg/kg wet weight. There were statistically significant differences in the content of cadmium, copper and zinc in different parts of the knee joint. There were no statistically significant differences in the content of cadmium, nickel, copper and zinc in women and men in the examined parts of the knee joint. Among the elements tested, copper and nickel showed a high content in the connective tissue (the meniscus) compared to the bone tissue (the tibia and the femur). 相似文献
993.
The study of change in intermediate phenotypes over time is important in genetics. In this paper we explore a new approach to phenotype definition in the genetic analysis of longitudinal phenotypes. We utilized data from the longitudinal Framingham Heart Study Family Cohort to investigate the familial aggregation and evidence for linkage to change in systolic blood pressure (SBP) over time. We used Gibbs sampling to derive sigma-squared-A-random-effects (SSARs) for the longitudinal phenotype, and then used these as a new phenotype in subsequent genome-wide linkage analyses. Additive genetic effects (sigma2A.time) were estimated to account for approximately 9.2% of the variance in the rate of change of SBP with age, while additive genetic effects (sigma2A) were estimated to account for approximately 43.9% of the variance in SBP at the mean age. The linkage results suggested that one or more major loci regulating change in SBP over time may localize to chromosomes 2, 3, 4, 6, 10, 11, 17, and 19. The results also suggested that one or more major loci regulating level of SBP may localize to chromosomes 3, 8, and 14. Our results support a genetic component to both SBP and change in SBP with age, and are consistent with a complex, multifactorial susceptibility to the development of hypertension. The use of SSARs derived from quantitative traits as input to a conventional linkage analysis appears to be valuable in the linkage analysis of genetically complex traits. We have now demonstrated in this paper the use of SSARs in the context of longitudinal family data. 相似文献
994.
995.
Lactobacillus delbrueckii was grown on sugarcane molasses, sugarcane juice and sugar beet juice in batch fermentation at pH 6 and at 40°C. After 72 h,
the lactic acid from 13% (w/v) sugarcane molasses (119 g total sugar l−1) and sugarcane juice (133 g total sugar l−1) was 107 g l−1 and 120 g l−1, respectively. With 10% (w/v) sugar beet juice (105 g total sugar l−1), 84 g lactic acid l−1 was produced. The optical purities of d-lactic acid from the feedstocks ranged from 97.2 to 98.3%. 相似文献
996.
Regulation of cyclin-dependent kinase inhibitor p21<Superscript>WAF1/CIP1</Superscript> by protein kinase Cδ-mediated phosphorylation 总被引:1,自引:0,他引:1
Oh YT Chun KH Park BD Choi JS Lee SK 《Apoptosis : an international journal on programmed cell death》2007,12(7):1339-1347
Cyclin-dependent kinase (CDK) inhibitor p21WAF1/CIP1(-/-)-null mice have an increased incidence of tumor formation. Here, we demonstrate that p21WAF1/CIP1 is unstable in HeLa cells treated with siRNA duplexes that target PKCδ. PKCδ phosphorylates p21WAF1/CIP1 at a serine residue (146Ser) located in its C-terminal domain. In cells treated with 12-O-tetradecanoylphorbol 13-acetate, the levels of both p21WAF1/CIP1 and its 146Ser-phosphorylated form increased significantly. We also show that a substitution, resulting from a single nucleotide polymorphism
(SNP) at 149Asp found in certain cancer patients, strongly compromises PKCδ-mediated phosphorylation at 146Ser and results in cells that are relatively resistant to TNFα-induced apoptosis. Thus, post-translational phosphorylation
of p21WAF1/CIP1 is important from an apoptotic cell death, and may also have patho-physiological relevance for the development of human cancer. 相似文献
997.
Palmroth MR Koskinen PE Kaksonen AH Münster U Pichtel J Puhakka JA 《Biodegradation》2007,18(6):769-782
In the current study, the microbial ecology of weathered hydrocarbon and heavy metal contaminated soil undergoing phytoremediation
was studied. The relationship of functional diversity, measured as carbon source utilisation in Biolog plates and extracellular
enzymatic activities, and genetic diversity of bacteria was evaluated. Denaturing gradient gel electrophoresis was used for
community analyses at the species level. Bulk soil and rhizosphere soil from pine and poplar plantations were analysed separately
to determine if the plant rhizosphere impacted hydrocarbon degradation. Prevailing microbial communities in the field site
were both genetically and metabolically diverse. Furthermore, both tree rhizosphere and fertilisation affected the compositions
of these communities and increased activities of extracellular aminopeptidases. In addition, the abundance of alkane hydroxylase
and naphthalene dioxygenase genes in the communities was low, but the prevalence of these genes was increased by the addition
of bioavailable hydrocarbons. Tree rhizosphere communities had greater hydrocarbon degradation potential than those of bulk
soil. Hydrocarbon utilising communities were dominated generally by the species Ralstonia eutropha and bacteria belonging to the genus Burkholderia. Despite the presence of viable hydrocarbon-degrading microbiota, decomposition of hydrocarbons from weathered hydrocarbon
contaminated soil over four years, regardless of the presence of vegetation, was low in unfertilised soil. Compost addition
enhanced the removal of hydrocarbons. 相似文献
998.
Tileye Feyissa Li-Hua Zhu Legesse Negash Margareta Welander 《Plant Cell, Tissue and Organ Culture》2007,88(3):277-288
The effects of growth regulators, wounding and antibiotics on regeneration of Hagenia abyssinica were investigated and the rolB gene was introduced into this species by Agrobacterium-mediated transformation. Regeneration was affected by type of growth regulators, wounding and antibiotics. Up to 100% regeneration
could be obtained. Three transformed clones (T1, T2.1, T2.2), confirmed by PCR and Southern blot, were obtained only by excluding
kanamycin from the selection medium 6 weeks after culture, followed by selection during shoot multiplication. RT-PCR revealed
strong expression of rolB gene in shoots and roots of all the transgenic clones, but from leaf samples, it was detected only in T1. Rooting frequency
was 77% (T1), 50% (T2.1), 57% (T2.2) and 0% for control shoots on growth regulator-free rooting medium. 相似文献
999.
We investigated clonal traits in the dioecious herb Rumex acetosella to characterize sexual dimorphism in clonal forms and to correlate below-ground clonal patterns and above-ground ramet distributions.
We recorded creeping root length, branching patterns, ramet and clump (caespitose ramets from the same position on the root)
sprouting patterns, and biomass allocations in three females and males. We also estimated the patch size of flowering ramets
within a quadrat. No sexual dimorphism was detected in the frequencies of branches and flowering ramets per root length. Male
plants allocated proportionally more biomass to below-ground organs. Total root length did not differ between the sexes. Females
sprouted more clumps with fewer flowering ramets per root length than males, which sprouted fewer clumps with more flowering
ramets, which meant that clump sprouting patterns were phalanx-like in females and guerrilla-like in males. Flowering ramets
were aggregately distributed in both females and males and patch sizes were similar between sexes, indicating that the spreader
propagations were not found in the guerrilla-like males. We assumed that sexual dimorphism occurred in response to physiological
integration for higher reproductive effort in females. 相似文献
1000.
The phylogenetic species richness of the bacteria in the gut of the termite Reticulitermes flavipes was examined using near full-length 16S rRNA gene sequencing and amplified rDNA restriction analysis (ARDRA). We amplified
the genes by polymerase chain reaction (PCR) directly from a mixed population of termite gut bacteria and isolated them using
cloning techniques. Sequence analysis of 42 clones identified a broad taxonomic range of ribotypes from six phyla within the
domain Bacteria: Proteobacteria, Spirochaetes, Bacteroidetes, Firmicutes, Actinobacteria, and the recently proposed “Endomicrobia.” Analysis of the sequence data suggested the presence of a termite specific bacterial lineage within Bacteroidetes. The ARDRA data included 261 different ARDRA profiles of 512 clones analyzed. These data suggest the gut flora in R. flavipes is extremely diverse. 相似文献