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91.
Tropheryma whipplei in the Environment: Survey of Sewage Plant Influxes and Sewage Plant Workers 下载免费PDF全文
Maximilian Schniger-Hekele Dagmar Petermann Beate Weber Christian Müller 《Applied microbiology》2007,73(6):2033-2035
We studied the prevalence of Tropheryma whipplei in influxes to 46 sewage treatment plants and in stool, mouthwash fluids, and dental plaques of 64 healthy workers in those facilities and 146 disease control patients. T. whipplei was found in sewage water, in stool of healthy individuals, and significantly more often in stool of workers exposed to sewage water. 相似文献
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The evolutionary development of mammals involves mutations and fixations of chromosomal types. The Y chromosome polymorphism in cattle is important for the breeding strategy, since chromosomal incompatibilities in crossings result in fertility problems. In bulls of various breeds in Switzerland, data on chromosome status have been collected for over 20 years. Data from 7 years were analysed in this study through chromosome measurements and their normalization. Some highly significant differences were found between the 7 groups of breeds, especially between Holsteins and the original Swiss breeds Braunvieh and Simmental. Fleckvieh (purebred or crossbred) did not differ significantly from Black or Red Holsteins. The results were discussed with respect to fertility problems. The observed Y chromosome polymorphism should be taken into account in breeding, and research in this field should be continued. 相似文献
95.
Functional interactions between Prp8, Prp18, Slu7, and U5 snRNA during the second step of pre-mRNA splicing 下载免费PDF全文
After the second transesterification step of pre-mRNA splicing, the Prp22 helicase catalyzes release of spliced mRNA by disrupting contacts in the spliceosome that likely involve Prp8. Mutations at Arg1753 in Prp8, which suppress helicase-defective prp22 mutants, elicit temperature-sensitive growth phenotypes, indicating that interactions in the spliceosome involving Prp8-R1753 might be broken prematurely at 37 degrees C. Here we report that mutations in loop I of the U5 snRNA or in Prp18 can suppress the temperature-sensitive prp8-R1753 mutants. The same gain-of-function PRP18 alleles can also alleviate the growth phenotypes of multiple slu7-ts mutants, indicating a functional link between Prp8 and the second step splicing factors Prp18 and Slu7. These findings, together with the demonstration that changes at Arg1753 in Prp8 impair step 2 of pre-mRNA splicing in vitro, are consistent with a model in which (1) Arg1753 plays a role in stabilizing U5/exon interactions prior to exon joining and (2) these contacts persist until they are broken by the helicase Prp22. 相似文献
96.
Widl K Brettschneider J Schattauer D Süssmuth S Huber R Ludolph AC Tumani H 《Neurochemical research》2007,32(7):1163-1168
We aimed to establish age-related reference values for Erythropoietin (EPO) in cerebrospinal fluid (CSF) and to evaluate concentrations
in neurological diseases. CSF and serum EPO was measured in controls with tension-type headache (CTTH), in patients with ALS,
dementia and depression using ELISA technique.
Stability experiments showed CSF EPO to be stable for two and a half months and over two thaw/freeze cycles. A positive correlation
of CSF EPO with age was found (P < 0.01). We found a CSF/serum EPO concentration ratio of 0.126, pointing towards an intrathecal synthesis of EPO. The ALS
group showed significantly lowered CSF EPO compared to age-matched CTTH (P < 0.012), whereas the dementia and depression group showed no significant differences compared to CTTH.
The establishment of age-related reference values in a large cohort of controls will improve the interpretation of future
CSF EPO evaluations in neurological diseases.
The authors have not reported any conflicts of interest. 相似文献
97.
van Donselaar E Posthuma G Zeuschner D Humbel BM Slot JW 《Traffic (Copenhagen, Denmark)》2007,8(5):471-485
Immunogold labeling of cryosections according to Tokuyasu (Tokuyasu KT. A technique for ultracyotomy of cell suspensions and tissues. J Cell Biol 1973;57:551–565), is an important and widely used method for immunoelectron microscopy. These sections are cut from material that is chemically fixed at room temperature (room temparature fixation, RTF). Lately in many morphological studies fast freezing followed by cryosubstitution fixation (CSF) is used instead of RTF. We have explored some new methods for applying immunogold labeling on cryosections from high‐pressure frozen cells (HepG2 cells, primary chondrocytes) and tissues (cartilage and exocrine pancreas). As immunolabeling has to be carried out on thawed and stable sections, we explored two ways to achieve this: (1) The section fixation method, as briefly reported before (Liou W et al. Histochem Cell Biol 1996;106:41–58 and Möbius W et al. J Histochem Cytochem 2002;50:43–55.) in which cryosections from freshly frozen cells were stabilized in mixtures of sucrose and methyl cellulose and varying concentrations of glutaraldehyde, formaldehyde and uranyl acetate (UA). Only occasionally does this method reveal section areas with excellent cell preservation and negatively stained membranes like Tokuyasu sections of RTF material. (Liou et al.) (2) The rehydration method, a novel approach, in which CSF with glutaraldehyde and/or osmium tetroxide (OsO4) was followed by rehydration and cryosectioning as in the Tokuyasu method. Especially, the addition of UA and low concentrations of water to the CSF medium favored superb membrane contrast. Immunogold labeling was as efficient as with the Tokuyasu method. 相似文献
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Intra‐thallus differentiation of fatty acid and pigment profiles in some temperate Fucales and Laminariales 下载免费PDF全文
Intra‐thallus variation in fatty acid and pigment contents and profiles was investigated in five species of Laminariales (Alaria esculenta, Laminaria digitata, Laminaria hyperborea, Saccharina latissima, and Saccorhiza polyschides), and three Fucales (Ascophyllum nodosum, Fucus serratus, and Himanthalia elongata). Significant variation occurred across all species and compounds examined. Total fatty acids were generally higher in the fronds, with highest levels and largest variability observed in A. nodosum (1.5% of dry weight (DW) in the base, 6.3% of DW in frond tips). Percentages of the omega‐3 fatty acids 18:4 n‐3 and 20:5 n‐3 were generally higher in more distal parts, while 20:4 n‐6 exhibited a contrasting pattern, with higher levels in basal structures and holdfasts. Trends for pigments were similar to those for fatty acids in Laminariales. In the Fucales, highest levels were detected in the mid‐fronds, with lower concentrations in meristematic areas. Highest levels and greatest variability in pigments (e.g., chl a) was observed in F. serratus (1.07 mg · g?1 DW in the base, 3.04 mg · g?1 DW in the mid frond). Intra‐thallus variability was attributed to physiological functions of the respective thallus sections, e.g., photosynthetic activity, meristematic tissue, and to variations in physical attributes of the structures investigated. Regarding potential commercial nutritional applications, fronds appeared to represent most suitable source materials, due to higher levels of pigments, polyunsaturated fatty acids, and more preferable omega‐3/omega‐6 ratios. 相似文献