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1.

Background

In humans, N-acetyl L-aspartate (NAA) has not been detected in other tissues than the brain. The physiological function of NAA is yet undefined. Recently, it has been suggested that NAA may function as a molecular water pump, responsible for the removal of large amounts of water from the human brain. Ovarian tumors typically present as large cystic masses with considerable fluid accumulation.

Methodology and Principal Findings

Using Gas Chromatography-Mass Spectrometry, we demonstrated that NAA was present in a high micromolar concentration in oCF of epithelial ovarian tumors (EOTs) of serous histology, sometimes in the same range as found in the extracellular space of the human brain. In contrast, oCF of EOTs with a mucinous, endometrioid and clear cell histological subtype contained a low micromolar concentration of NAA. Serous EOTs have a cellular differentiation pattern which resembles the lining of the fallopian tube and differs from the other histological subtypes. The NAA concentration in two samples of fluid accumulation in the fallopian tube (hydrosalpinx) was in the same ranges as NAA found in oCF of serous EOTs. The NAA concentration in oCF of patients with serous EOTs was mostly 10 to 50 fold higher than their normal serum NAA concentration, whereas in patients with other EOT subtypes, serum and cyst fluid NAA concentration was comparable.

Conclusions and Significance

The high concentration of NAA in cyst fluid of serous EOTs and low serum concentrations of NAA in these patients, suggest a local production of NAA in serous EOTs. Our findings provide the first identification of NAA concentrations high enough to suggest local production outside the human brain. Our findings contribute to the ongoing research understanding the physiological function of NAA in the human body.  相似文献   

2.
The P2 contents of nervous tissues from the human, rabbit, guinea pig, and Lewis rat were measured by radioimmunoassay. The ventral spinal roots contained more P2 than any other tissue. Human dorsal roots and peripheral nerves contained 41-65% of the amount in human ventral roots. Human olfactory and optic nerves and brain contained 1.1-2.7%, spinal cord, 2.8%, cranial nerve VIII, 11%, and cerebral grey matter, 0%. The relative amounts in the rabbit nervous system were similar except that the spinal cord contained 20% of the amount in the ventral roots. Qualitative estimates in the guinea pig showed that the spinal roots and peripheral nerves contained more P2 than the spinal cord, and that none was present in the brain. In the Lewis rat, P2 could be detected in the spinal roots and peripheral nerves but not in the CNS. The distribution of P2 in the human nervous system parallels the incidence and severity of lesions in acute polyradiculoneuritis. It also explains the absence of any lesions in the CNS when experimental allergic neuritis is induced in the Lewis rat.  相似文献   

3.
Carotenoid content of tobacco tissue grown in suspension culture was significantly affected by 2 mg . 1-1 I-naphthaleneacctic acid (NAA) and 500 mg . 1-1 (2-chloroethyl)-trimethyl-ammonium chloride (CCC). CCC caused a 4-fold increase of carotenoid concentration in the tissue and a 2-fold increase of carotenoid accumulation per one cultural flask mainly due to the appearance of significant amounts of lycopene. In the absence of NAA the tissue contained a much smaller amount of carotenoids and CCC failed to induce lycopene accumulation.  相似文献   

4.
The ganglioside composition of surgically removed human glioma tissue was shown to differ from that of normal adult brain tissue. First, it contained reduced amounts of the major normal brain gangliosides of the gangliotetraose series. Second, it contained increased proportions of gangliosides not detected in normal brain tissue. One of these was isolated and established as being sialyllactotetraosylceramide 3'-isoLM1. Radioimmunoassay for this ganglioside antigen in human glioma tissue revealed that 14/14 specimens of grades III and IV were positive but only 1/4 of grade II. Normal brain tissue was negative. These results suggest that sialyllactotetraosylceramide is a marker for human malignant gliomas.  相似文献   

5.
The content, types and the fine structures of proteoglycans (PGs) present in human normal nasal cartilage (HNNC) were investigated and compared with those in human scoliotic nasal cartilage (HSNC). Three PG types were identified in both HNNC and HSNC; the large-sized high buoyant density aggrecan, which is the predominant PG population, and the small-sized low buoyant density biglycan and decorin. HSNC contained a significantly higher amount of keratan sulfate (KS)-rich aggrecan (30%) of smaller hydrodynamic size as compared to HNNC. The average molecular sizes (Mrs) of aggecan-derived chondroitin sulfate (CS) chains in both HNNC and HSNC were identical (18 kDa), but they significantly differ in disaccharide composition, since CS isolated from HSNC contained higher proportions of 6-sulfated disaccharides as compared to those from HNNC. Scoliotic tissue contained also higher amounts (67%) of the small PGs, biglycan and decorin as compared to HNNC. It is worth noticing that both normal and scoliotic human nasal cartilage contain also non-glycanated forms of decorin and biglycan. Dermatan sulfate (DS) was the predominant glycosaminoglycan (GAG) present on biglycan and decorin in both tissues. The small PGs-derived CS chains in both normal and scoliotic cartilage had the same Mr (20 kDa), whereas DS chains from scoliotic cartilage were of greater Mr (32 kDa) than those from normal cartilage (24 kDa). Furthermore, scoliotic tissue-derived DS chains contained higher amounts of iduronate (20%) as compared to those of normal cartilage (12%). Disaccharide analysis of small PGs showed that both HNNC and HSNC were rich in 4-sulfated disaccharides and in each case, the small size PGs contained a considerably higher proportion of 4-sulfated disaccharides than the aggrecan of the same tissue. The higher amounts of matrix PGs identified in scoliotic tissue as well as the differences in fine chemical composition of their GAG chains may reflect the modified architecture and functional failure of scoliotic tissue.  相似文献   

6.
7.
Free sphingoid bases in normal murine tissues   总被引:6,自引:0,他引:6  
Free sphingoid bases, which have been considered not to occur naturally, were detected in murine tissues by derivatization with o-phthalaldehyde and the use of high-performance liquid chromatography. The concentrations were 10-30 pmol/mg tissue. The lung contained the largest amounts of sphingoid bases. In the molecular species of sphingoid bases, the most abundant was C18-sphingenine followed by C18-sphinganine, 4-hydroxysphinganine and C20-sphingenine, in that order. The central nervous tissues contained relatively high amounts of C20-sphingenine and there was a high concentration of 4-hydroxysphinganine in the kidney. In addition, galactosylsphingenine was detected simultaneously in the spinal cord and sciatic nerve. Sphingoid bases were purified from normal murine lungs using lipid-extraction, cation-exchange and silicic acid column chromatographies, alkaline saponification and preparative thin-layer chromatography. In the purified sphingoid bases, erythro-C18-sphingenine and erythro-C18-sphinganine were identified using thin-layer chromatography, high-performance liquid chromatography and fast-atom-bombardment mass spectrometry. Free sphingoid bases occurring in normal tissues may be metabolic intermediates required for the synthesis or be products of degradation of the sphingolipids and function to regulate cellular metabolism.  相似文献   

8.
The content, types and the fine structures of proteoglycans (PGs) present in human normal nasal cartilage (HNNC) were investigated and compared with those in human scoliotic nasal cartilage (HSNC). Three PG types were identified in both HNNC and HSNC; the large-sized high buoyant density aggrecan, which is the predominant PG population, and the small-sized low buoyant density biglycan and decorin. HSNC contained a significantly higher amount of keratan sulfate (KS)-rich aggrecan (30%) of smaller hydrodynamic size as compared to HNNC. The average molecular sizes (M(r)s) of aggecan-derived chondroitin sulfate (CS) chains in both HNNC and HSNC were identical (18 kDa), but they significantly differ in disaccharide composition, since CS isolated from HSNC contained higher proportions of 6-sulfated disaccharides as compared to those from HNNC. Scoliotic tissue contained also higher amounts (67%) of the small PGs, biglycan and decorin as compared to HNNC. It is worth noticing that both normal and scoliotic human nasal cartilage contain also non-glycanated forms of decorin and biglycan. Dermatan sulfate (DS) was the predominant glycosaminoglycan (GAG) present on biglycan and decorin in both tissues. The small PGs-derived CS chains in both normal and scoliotic cartilage had the same M(r) (20 kDa), whereas DS chains from scoliotic cartilage were of greater M(r) (32 kDa) than those from normal cartilage (24 kDa). Furthermore, scoliotic tissue-derived DS chains contained higher amounts of iduronate (20%) as compared to those of normal cartilage (12%). Disaccharide analysis of small PGs showed that both HNNC and HSNC were rich in 4-sulfated disaccharides and in each case, the small size PGs contained a considerably higher proportion of 4-sulfated disaccharides than the aggrecan of the same tissue. The higher amounts of matrix PGs identified in scoliotic tissue as well as the differences in fine chemical composition of their GAG chains may reflect the modified architecture and functional failure of scoliotic tissue.  相似文献   

9.
10.
The glycosphingolipids of normal human lymphocytes from individual donors were analysed by high-pressure liquid chromatography. In addition, purified T- and B-lymphocytes were examined separately. Lactosylceramide was shown to be the major neutral glycosphingolipid in human lymphocytes, and monohexosylceramide, trihexosylceramide, globoside and paragloboside were all detected in smaller amounts. Analysis of purified B- and T-cell fractions revealed that each of these populations contained a similar qualitative profile for neutral glycosphingolipids, but that quantitatively, B-cells contained several times more of each glycosphingolipid per cell than did T-cells.  相似文献   

11.
Abstract: A simple and sensitive gas-chromatographic method for the determination of N-acetyl- l -aspartic acid (NA-Asp), N-acetyl-α-aspartylglutamic acid (NA-Asp-Glu) and β-citryl- l -glutamic acid (β-CG) was developed. The organ, regional and phylogenetic distributions of these compounds were studied. NA-Asp and NA-Asp-Glu were highly concentrated in nervous tissue, and less than 1% of the amounts in the nervous tissues were found in nonnervous organs. These two compounds showed a reciprocal relationship in their regional distribution in mature brains, but such a relationship was not evident or was even reversed in immature brains. The two compounds also showed different developmental changes in different regions of the brain. Fish brain contained a relatively high concentration of NA-Asp, but only a trace amount of NA-Asp-Glu. By contrast, a 10 times higher concentration of NA-Asp-Glu than NA-Asp was found in frog brain. Reptilian brain contained similar amounts of each compound. Avian and mammalian brain had NA-Asp at a roughly 10 times higher concentration than NA-Asp-Glu. β-CG occurred at the highest concentration in the immature brain of rat and guinea pig, but disappeared in the mature brains. The adult frog brain, however, contained a large amount of β-CG. In the adult rat, testis contained the highest concentration of β-CG.  相似文献   

12.
Investigations were carried out to determine levels of biogenic monoamines in the central nervous tissue of seven species of terrestrial gastropods (taxonomic family: Helicidae) using high-performance liquid chromatography (HPLC) with electrochemical detection (ELCD). The central nervous tissue of all species examined contained assayable amounts of dopamine (DA) and serotonin (5-HT). Noradrenaline (NA) was occasionally present; adrenaline (A) could not be detected. The central ganglia of two Mediterranean species generally contain 3-4 times more 5-HT relative to DA than the ganglia of the other species which contain amounts of 5-HT only slightly higher than DA.  相似文献   

13.
beta-Hexosaminidase (EC 3.2.1.20; Hex) activity and isoenzyme characteristics were analyzed in human normal and leukemic leukocytes. Unseparated CLL and CML cells had a specific activity that was lower, whereas ALL and AML blasts had a higher specific activity than normal lymphocytes and granulocytes. CLL B-cells had a lower specific activity compared with that in normal non-T-lymphocytes; CLL T-cells and normal T-cells had similar activity. Isoenzyme separation was performed by chromatofocusing on PBE-94 coupled with an automated enzyme assay. When using a single linear pH elution gradient, normal leukocytes and all leukemia cells contained two forms of isoenzyme (B and A). When a double pH elution gradient was performed, an extra distinct form of Hex (I) was recorded. Hex I was present in small amounts in normal granulocytes and PHA-stimulated normal lymphocytes; isoenzyme I was found in high amounts in all leukemias tested. The activity ratios I/B and I/A, as well as the I isoenzyme profile, may facilitate differentiation between normal and leukemic cells and between lymphoblastic and myeloblastic leukemias.  相似文献   

14.
Meristems of Ophiopogon japonicus (Liliaceae) were grown on a modified MS medium without auxins or cytokinins and plantlets and embryogenic callus were obtained at a low frequency. When meristems growing on modified basal medium were briefly soaked in 0.54 mM naphtaleneacetic acid (NAA) or temporarily grown on medium that contained NAA or NAA and benzyladenine, a larger proportion of meristems developed into plantlets or produced callus and additional plantlets following their return to basal medium. Calluses grown in liquid culture without auxins or cytokinins produced abundant single cells and cell aggregates. Larger cell aggregates formed embryo-like structures that produced roots, cotyledons, and then plantlets following transfer to soilid medium. Prolonged liquid culture produced embryo-like structures directly in liquid medium. These structures met many of the criteria for somatic embryos and developed into normal plantlets when placed on solid medium.  相似文献   

15.
Gangliosides, cholesterol, and phospholipids were quantitated in the tissues of 11 human neural tumors and the cells of two gliomas cultured in vitro. All tumor tissues contained higher water concentrations but lower total lipid concentrations than either human grey or white matter. In general they contained less cholesterol, sphingomyelin, and serine glycerophospholipid but more choline glycerophospholipid than white matter. Concentrations of total ganglioside sialic acid were intermediate between grey and white matter. Compared with normal brain, all tumors had greater proportions of the structurally less complex gangliosides and smaller proportions of the more complex gangliosides. This was most marked in the rapidly growing tumors while the better differentiated astrocytomas contained the greatest proportions of complex gangliosides. The cells of the cultured tumors contained amounts of total lipid and total phospholipid similar to their parent tissues. However, the cultures had less cholesterol, sphingomyelin, and total ganglioside than their parent tissues. There were significant amounts of choline and ethanolamine plasmalogens in both cultures and parent tissues. The ganglioside patterns of both cultures were complex but they contained a greater proportion of structurally simpler gangliosides than their parent tissues.-Yates, A. J., D. K. Thompson, C. P. Boesel, C. Albrightson, and R. W. Hart. Lipid composition of human neural tumors.  相似文献   

16.
Soybean somatic embryogenesis: interactions between sucrose and auxin   总被引:6,自引:0,他引:6  
The interaction between sucrose and auxin in soybean (Glycine max L. Merr.) somatic embryogenesis was investigated by culturing immature cotyledon explants on factorial combinations of NAA (6.25, 12.5, 25 and 50 mg/l) and sucrose (0.5, 1, 2 and 4%). A significant interaction between sugar and auxin was observed; balanced concentrations of the two components were required for optimal embryo production and normality. The highest numbers of normal somatic embryos were produced on media which contained combinations of low to intermediate levels of sucrose (1 or 2%) and NAA (6.25 or 12.5 mg/l). Cotyledon explants from induction media having a low (0.5%) sucrose content showed the most efficient embryogenesis in secondary culture. The highest frequencies of germination (32 to 41%) were seen among embryos induced on media containing 0.5% sucrose.Abbreviations BAP 6-benzylaminopurine - NAA 1-naphthaleneacetic acid This paper (No. 88-3-161) is published with the approval of the Director of the Kentucky Agricultural Experiment Station.  相似文献   

17.
Transthyretin cDNA was isolated from a rat liver cDNA library. Analysis of the nucleotide sequence revealed a signal peptide-like sequence preceding a section coding for a full length subunit and an untranslated sequence at the 3' end. The deduced primary structure of rat transthyretin was compared with that of human transthyretin. It was highly conserved at the binding sites for thyroxine and the interfaces and core regions of the subunits. The cDNA for transthyretin was used to measure mRNA levels by hybridization. During acute inflammation, the amount of transthyretin mRNA in liver decreased (reaching a minimum of 25% of the normal level 36 h after inducing inflammation), suggesting regulation of transthyretin synthesis at the mRNA level. Transthyretin mRNA was found only in the liver and in the choroid plexus, but not in other parts of the central nervous system nor in the adrenal glands, kidney, spleen, testes, heart, lung, intestine, and ovaries. One gram of choroid plexus contained about 25 times larger amounts of transthyretin mRNA than 1 g of liver. By synthesizing an important hormone carrier protein, the choroid plexus may be an important link in the chemical communication between the central nervous system and the bloodstream.  相似文献   

18.
A highly reproducible procedure was developed for gas-liquid chromatographic analysis of trimethylsilyl derivatives of normal human cerebrospinal fluid. Fourteen normal human cerebrospinal fluid samples tested with this procedure contained alpha- and beta-glucose as well as isomers of two unidentified sugars. Chromatographic changes in three cases of meningeal inflammation (two cryptococcosis and one thalamic astrocytoma) were limited to decreased concentrations of all sugars. In one case of early meningitis, the concentrations of the unknown sugars decreased before glucose. Now that a reproducible chromatogram of the trimethylsilyl derivatives of normal human cerebrospinal fluid has been established, more samples of abnormal cerebrospinal fluid should be prepared by these methods and examined by gas-liquid chromatography. It may be possible to identify unique products of infectious agents which will permit rapid diagnosis of central nervous system infection.  相似文献   

19.
Molecular defect in processing alpha-fucosidase in fucosidosis   总被引:2,自引:0,他引:2  
In normal human skin fibroblasts, an enzymatically active 53,000-dalton form of alpha-fucosidase is processed to a 50,000-dalton mature form. Endoglycosidase-H treatment of [35S]methionine pulse-chase labelled material immunoprecipated with a polyclonal antibody to alpha-L-fucosidase (Andrews-Smith & Alhadeff, Biochim. Biophys. Acta 715: 90-96 (1982)) indicated the removal of a single N-linked oligosaccharide unit from both precursor and mature form of alpha-L-fucosidase. Tunicamycin pretreatment of normal fibroblasts indicated that no other N-linked oligosaccharide units were present. Studies on fibroblasts from patients with less than 5% of normal alpha-L-fucosidase activity (fucosidosis) showed 8 of 11 patients synthesized no detectable alpha-fucosidase protein whereas 2 synthesized normal amounts of 53,000 dalton precursor, none of the mature 50,000 dalton form was detectable and one contained small amounts of cross-reacting material. This is the first evidence for processing of alpha-L-fucosidase in cells and the first precise evidence of a molecular defect in fucosidosis.  相似文献   

20.
Myelin was prepared from the brachial plexus and cervical spinal cord of adult squirrel monkeys (Saimiri sciureus). Brachial plexus myelin contained a larger amount of sphingomyelin and smaller amounts of cholesterol, lipid galactose, ethanolamine phosphoglyceride, choline phosphoglyceride, and alk-1-enyl ether than spinal cord myelin when compared as ratios to total lipid phosphorus. The peripheral nervous system myelin had a higher proportion of protein. All of these differences were statistically significant. Thus peripheral nervous system myelin and central nervous system myelin differ in protein content and lipid composition in this subhuman primate.  相似文献   

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