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排序方式: 共有323条查询结果,搜索用时 46 毫秒
61.
P G Pentchev H S Kruth M E Comly J D Butler M T Vanier D A Wenger S Patel 《The Journal of biological chemistry》1986,261(35):16775-16780
Low density lipoprotein (LDL) internalization by mutant type C Niemann-Pick (NPC) fibroblasts results in uptake of excess total cholesterol. Uptake of excess lipoprotein cholesterol appears to be mediated by the specific LDL receptor pathway. Associated with excessive LDL-cholesterol uptake is a lesion in early intracellular cholesteryl ester synthesis. In vitro acylCoA:cholesterol acyltransferase activity is normal in cell-free extracts of mutant cells. The ability of exogenous sterols to enhance intracellular esterification of [3H]mevalonate-derived [3H]cholesterol was severely limited in mutant cell cultures suggesting that in vivo activation and/or expression of activated acylCoA:cholesterol acyltransferase may be compromised by the primary mutation of type C Niemann-Pick disease. After 2 days of LDL uptake, rates of intracellular cholesteryl ester synthesis in mutant cells paralleled the rates of esterification in normal cells suggesting that specific early in vivo expression of the acyltransferase may be affected in this disorder. 相似文献
62.
DEVELOPMENTAL PROFILES OF GANGLIOSIDES IN HUMAN AND RAT BRAIN 总被引:23,自引:13,他引:10
Abstract— The developmental profiles of individual gangliosides of human brain were compared with those of rat brain. Interest was focused mainly on the pre- and early postnatal development. Human frontal lobe cortex covering the period from 10 foetal weeks to adult age and the cerebrum of rat from birth to 21 days were analysed. Lipid-NANA and lipid-P were followed; in the rat, also protein and brain weight. A limited number of samples of human cerebral white matter and cerebellar cortex were also studied. The following major results were obtained:
- 1 The ganglioside concentration increased approximately three-fold within a short period: in rat cerebrum, from birth to the 17th day; in human cerebral cortex, from the 15th foetal week to the age of about 6 months. The largest increase in the rat brain occurred by the 11th to the 13th day; in human brain by term. The relative increase of gangliosides during this period was more rapid than that of phospholipids.
- 2 A hitherto unknown distinct early period of ganglioside and phospholipid formation in rat occurred by the second to fourth day.
- 3 The changes in brain ganglioside pattern, characteristic of the developmental stages of the rat, were found to be equally pronounced in the human brain.
- 4 Regional developmental differences in the ganglioside pattern were demonstrated in human brain. A characteristic white matter pattern, rich in monosialogangliosides, had developed by the age of 1 year. The increase in ganglioside concentration and the formation of the definitive ganglioside pattern of cerebellar cortex occurred later than in cerebral cortex. This cerebellar pattern was characterized by a very large trisialoganglioside fraction.
- 5 The two periods of rapid ganglioside metabolism in rat brain preceded the two periods of rapid protein biosynthesis.
63.
64.
Hajimohammadi Bahador Ahmadian Salman Firoozi Zohre Askari Maryam Mohammadi Masoud Eslami Gilda Askari Vahideh Loni Elahe Barzegar-Bafrouei Raziyeh Boozhmehrani Mohammad Javad 《EcoHealth》2022,19(1):55-74
EcoHealth - Toxoplasma gondii causes toxoplasmosis with a global prevalence in the world. A large proportion of human illness is most frequently associated with consuming raw and undercooked meat... 相似文献
65.
66.
Silva AF Carvalho G Soares R Coelho AV Barreto Crespo MT 《Applied microbiology and biotechnology》2012,95(3):767-776
Extracellular polymeric substances (EPS) are keys in biomass aggregation and settleability in wastewater treatment systems. In membrane bioreactors (MBR), EPS are an important factor as they are considered to be largely responsible for membrane fouling. Proteins were shown to be the major component of EPS produced by activated sludge and to be correlated with the properties of the sludge, like settling, hydrophobicity and cell aggregation. Previous EPS proteomic studies of activated sludge revealed several problems, like the interference of other EPS molecules in protein analysis. In this study, a successful strategy was outlined to identify the proteins from soluble and bound EPS extracted from activated sludge of a lab-scale MBR. EPS samples were first subjected to pre-concentration through lyophilisation, centrifugal ultrafiltration or concentration with a dialysis membrane coated by a highly absorbent powder of polyacrylate-polyalcohol, preceded or not by a dialysis step. The highest protein concentration factors were achieved with the highly absorbent powder method without previous dialysis step. Four protein precipitation methods were then tested: acetone, trichloroacetic acid (TCA), perchloric acid and a commercial kit. Protein profiles were compared in 4–12 % sodium dodecyl sulphate polyacrylamide gel electrophoresis gels. Both acetone and TCA should be applied for the highest coverage for soluble EPS proteins, whereas TCA was the best method for bound EPS proteins. All visible bands of selected profiles were subjected to mass spectrometry analysis. A high number of proteins (25–32 for soluble EPS and 17 for bound EPS) were identified. As a conclusion of this study, a workflow is proposed for the successful proteome characterisation of soluble and bound EPS from activated sludge samples. 相似文献
67.
Flow cytometry phenotypization of thyroidal lymphoid infiltrate and functional status in Hashimoto's thyroiditis 总被引:1,自引:0,他引:1
Zeppa P Marino G Lepore M Troncone G Lupoli GA Biondi B Picardi M Pane F Vetrani A Palombini L 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2006,28(3):148-156
OBJECTIVE: To evaluate the thyroidal lymphoid infiltrate (TLI) in thyroidal functional status (TFS) for differences among patients with Hashimoto's thyroiditis (HT). STUDY DESIGN: Flow-cytometry (FC) was applied to thyroidal fine-needle cytology samples in 57 patients. TLI was analyzed using a fluorescence-activated cell sorter (FACS) scan and fluorescence antibodies CD3, CD4, CD5, CD8, CD10, and CD19 and kappa and lambda light chains. TFS was determined by serum thyroid-stimulating hormone (TSH), FT3 and FT4 immunoassays, in specific clinical settings, to classify the cases as hyperthyroid, euthyroid and hypothyroid. FC assessment was then compared with the corresponding TFS. RESULTS: B-lymphocytes were present in 44 cases (77%). T-lymphocytes were present in all the cases; CD4/CD8 = 2:1 ratio was observed in 16 euthyroid, 1 hyperthyroid and 3 hypothyroid; CD4/CD8 > or = 3:1 ratio in 22 euthyroid, 2 hyperthyroid and 2 hypothyroid cases; CD4/CD8 < or = 1:1 ratio in 1 euthyroid, 3 hyperthyroid and in 7 hypothyroid cases. Grouping hyperthyroid and hypothyroid cases, a significant association was observed with the CD4/CD8 < or = 1:1 ratio (p < 0.01). CONCLUSION: Intrathyroidal CD4/CD8 < 1:1 ratio might be the expression of intense apoptosis in the early phases of HT, generally followed by the restoration of CD4/CD8 balance; persistence of increased intrathyroidal CD8 might be related to intense thyroidal damage and thus an increasing risk of hypothyroidism. 相似文献
68.
Weber D Erosa G Sterner O Anke T 《Zeitschrift für Naturforschung. C, Journal of biosciences》2006,61(9-10):663-669
The metabolites of two different Ripartites species, R. tricholoma (A. & S. ex Fr.) Karst. and R. metrodii Huijsm. were investigated. Three new sesquiterpenes were isolated from three different strains. In addition, the strains produced 13-oxo-9(Z),11(E)-octadecadienoic acid, psathyrellon A, 5-desoxyilludosin, an illudane (previously isolated from a Bovista sp.) 96042 and demethylovalicin, five known compounds. 相似文献
69.
Filomena Freitas Margarida F. Temudo Gilda Carvalho Adrian Oehmen Maria A.M. Reis 《Bioresource technology》2009,100(6):1969-1976
In this study, it is proposed that short sequencing batch reactor (SBR) cycles select and maintain a robust and active biomass, able to cope with typical disturbances occurring in wastewater treatment plants. In order to test this hypothesis, an SBR system was subjected to COD, N and P shock loads. It was shown that the sludge enriched in the SBR operated with short cycles was able to rapidly recover from the tested disturbances. COD and N removal recovered within 1–2 days for shock loads of 10 times the standard concentration. The P removal took up to 2–3 sludge ages to fully recover from the COD spike, but the enhanced biological phosphorus removal (EBPR) performance was still able to be totally re-established after each of the tests, even in theoretically adverse conditions for the growth of polyphosphate accumulating organisms. 相似文献
70.
Malinowska M Wilkinson FL Langford-Smith KJ Langford-Smith A Brown JR Crawford BE Vanier MT Grynkiewicz G Wynn RF Wraith JE Wegrzyn G Bigger BW 《PloS one》2010,5(12):e14192