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PubMed2002

Gliomatosis peritonei: a report of two cases and review of the literature.

Gliomatosis peritonei is the implantation of miliary glial tissue within the peritoneal cavity of patients with ovarian teratomas. Up to now 86 cases of this rare entity have been reported. In addition to the small number of reported gliomatosis peritonei cases, a condition easily mistaken for peritoneal carcinomatosis, we report two further cases, one combined with endometriosis (fifth case published until now) and one without endometriosis. Both cases were followed up for more than 5.5 years. Thus, further data concerning biological behaviour and prognosis of this rare entity are made available. In addition, a review of all cases published until today is provided, thus summarising the data presently known.

Abdominal Pain↗

PubMed2002

Overexpressed protein disulfide isomerase in brains of patients with sporadic Creutzfeldt-Jakob disease.

Earlier studies have failed to detect covalent modifications in beta-sheet-rich scrapie isoform prion protein (PrP(Sc)) and have concluded that the conversion of alpha-helix-rich cellular form prion protein (PrP(C)) to PrP(Sc) represents purely conformational transition not involving chemical reactions. However, recent studies have shown that the intradisulfide bond of PrP(C) can play an important role for instability and conformational change to PrP(Sc). Interestingly, we found overexpressed protein disufide isomerase (PDI) in brains of sporadic Creutzfeldt-Jakob disease (sCJD, human prion disease) patients using two dimensional electrophoresis and Western blot analysis but not in other neurodegenerative disorders as Down Syndrome and Alzheimer's disease. However, proteinase K digestion and plasminogen binding assay of brain homogenates incubated with PDI suggest that PDI has no effect on either proteinase resistance or conformational change of PrP. Overexpression of PDI protein in sCJD brain may simply reflect a cellular defense response against the altered prion protein.

Aged↗

PubMed2001

Prediction of peptide ion mobilities via a priori calculations from intrinsic size parameters of amino acid residues.

Ion mobility spectrometry (IMS) has recently been established as a powerful tool to separate the protease digest mixtures and identify their peptide components. As accurate calculation of mobilities is critical for this technique, a new rapid method based on intrinsic size parameters (ISPs) of amino acid residues has been devised. However, those parameters had to be obtained by tedious statistical analysis of a large body of experimental data. Here we demonstrate that they can instead be derived a priori, based on the stoichiometry of a residue. Our main finding is that the ISP of a residue is essentially determined by its density, that is, the average mass/size ratio of its constituent atoms. This is in accordance with an interpretation in which peptides assume compact conformations in the gas phase dominated by the solvation of ionic charge.

Algorithms↗

PubMed2003

Biochemical markers of cerebrospinal ischemia after repair of aneurysms of the descending and thoracoabdominal aorta.

OBJECTIVE: To investigate the clinical potential of several markers of spinal cord ischemia in cerebrospinal fluid (CSF) and serum during aneurysm repair of the descending thoracic or thoracoabdominal aorta. DESIGN: Observational study of consecutive patients. Nonblinded, nonrandomized. SETTING: University hospital thoracic surgical unit. PARTICIPANTS: Eleven consecutive elective patients. INTERVENTIONS: Distal extracorporeal circulation and maintenance of CSF pressure <10 mmHg until intrathecal catheter removal. MEASUREMENTS AND MAIN RESULTS: CSF and serum levels of S100B (and its isoforms S100A1B and S100BB), neuronal-specific enolase (NSE), and the CSF levels of glial fibrillary acidic protein (GFAp) and lactate were determined. Two patients had postoperative neurologic deficit. One with a stroke showed a 540-fold increased GFAp, a 6-fold NSE, and S100B increase in CSF. One with paraplegia had a 270-fold increase in GFAp, a 2-fold increase in NSE, and 5-fold increased S100B in CSF. One patient without deficit increased GFAp 10-fold, NSE 4-fold, and S100B 23-fold in CSF. CSF lactate increased >50% in 6 of 9 patients without neurologic deficit. Serum S100B increased within 1 hour of surgery in all patients without any concomitant increase in CSF. S100A1B was about 70% of total S100B in both serum and CSF in patients with or without neurologic defects. S100B in CSF increased 3-fold in 3 of 9 asymptomatic patients. CONCLUSIONS: In patients with neurologic deficit, GFAp in CSF showed the most pronounced increase. Biochemical markers in CSF may increase without neurologic symptoms. There is a significant increase in serum S100B from surgical trauma alone without any increase in CSF.

Adult↗

PubMed1991

Mechanism of enolase: the crystal structure of enolase-Mg2(+)-2-phosphoglycerate/phosphoenolpyruvate complex at 2.2-A resolution.

Enolase in the presence of Mg2+ catalyzes the elimination of H2O from 2-phosphoglyceric acid (PGA) to form phosphoenolpyruvate (PEP) and the reverse reaction, the hydration of PEP to PGA. The structure of the ternary complex yeast enolase-Mg2(+)-PGA/PEP has been determined by X-ray diffraction and refined by crystallographic restrained least-squares to an R = 16.9% for those data with I/sigma (I) greater than or equal to 2 to 2.2-A resolution with a good geometry of the model. The structure indicates the substrate molecule in the active site has its hydroxyl group coordinated to the Mg2+ ion. The carboxylic group interacts with the side chains of His373 and Lys396. The phosphate group is H-bonded to the guanidinium group of Arg374. A water molecule H-bonded to the carboxylic groups of Glu168 and Glu211 is located at a 2.6-A distance from carbon-2 of the substrate in the direction of its proton. We propose that this cluster functions as the base abstracting the proton in the catalytic process. The proton is probably transferred, first to the water molecule, then to Glu168, and further to the substrate hydroxyl to form a water molecule. Some analogy is apparent between the initial stages of the enolase reverse reaction, the hydration of PEP, and the proteolytic mechanism of the metallohydrolases carboxypeptidase A and thermolysin. The substrate/product binding is accompanied by large movements of loops Ser36-His43 and Ser158-Gly162. The role of these conformational changes is not clear at this time.

Amino Acid Sequence↗

PubMed1982

Binding of fluoride by yeast enolase.

The kinetics of fluoride binding by yeast enolase have been examined by direct measurement of equilibrium fluoride (F) concentrations with an ion-specific electrode. Mg2+ and inorganic phosphate (Pi) affect the binding of F, and evidence is presented for an ordered binding mechanism in which phosphate and F interact with conformational and catalytic Mg2+ species, with the overall formation of a quaternary complex. A maximum of four atoms of F were bound per enzyme dimer, and the data point to the nonequivalent binding of pairs of F atoms. The dissociation constants were 5.0 X 10(-4) M and 8.2 X 10(-5) M for the first and second pairs of F atoms, respectively. The first pair of binding sites was filled when the ratio of phosphate ions/enolase dimer exceeded 2 and appeared to involve the pair of conformation Mg2+ ions. The binding of the second pair of F atoms followed the binding of catalytic Mg2+ in the presence of Pi and, furthermore, appeared to exhibit positive cooperativity with respect to F. The data suggest, also, that the binding of Pi may involve sequential addition of Pi pairs to the different Mg2+ species on the enzyme. F binding was at a maximum between pH 5.5 and pH 6.0, consistent with an involvement of the monovalent form of Pi. In the absence of added Pi, (MgF)+ appeared to be the preferred ligand. Addition of the enzyme substrate 2-phosphoglycerate led to the release of bound F. These findings are consistent with the known patterns of inhibition of enzymatic activity by F.

Dose-Response Relationship, Drug↗

PubMed2003

Immunohistochemical localization of human pineal tissue antigens in normal retina and retinoblastomas.

The normal human retina and retinoblastomas were examined immunohistochemically to assess the localization of pineal antigens in the retina and the oncogenesis and differentiation of retinoblastoma. In the present study, 41 eyes excised from children (aged 4 months to 7 years, all unilateral occurrence) diagnosed to have retinoblastoma and 4 eyes with normal retinas, were used. Retinoblastomas were histopathologically classified into well-differentiated, moderately-differentiated, and poorly-differentiated types. The antibodies used were 9 monoclonal antibodies to human pineal antigens and 6 antibodies to neural tissues. In the normal retina, staining patterns characteristic of retinal cell layers were observed with PP1, PP3, PP5, PP6, PI1, and PI2 antibodies. In retinoblastomas, PP5 antibody, which reacts with horizontal cells and ganglion cells, and PP6 antibody, which reacts with part of the bipolar cells in the inner nuclear layer, showed intense staining in well-differentiated retinoblastomas, but the intensity of staining and the positivity decreased with the degree of dedifferentiation. Antigens recognized by PP3 and PP4 antibodies were positive in all retinoblanstomas. Reactions to GFAP antibody and antibodies that recognize Müller cells were negative. Retinoblanstomas may express markers of not only photoreceptor cells but also other retinal nuclear cells. These results suggest that the retinoblastoma might be developed from visual stem cells, which are common progenitor cells of photoreceptor cells, intermediate neurons, and ganglion cells.

Antibodies, Monoclonal↗

PubMed2006

Control analysis of the importance of phosphoglycerate enolase for metabolic fluxes in Lactococcus lactis subsp. lactis IL1403.

The glycolytic enzyme phosphoglycerate enolase (PGE) catalyses the step from 2-phosphoglycerate to phosphoenolpyruvate in glycolysis. A control analysis of PGE on growth, glycolytic flux and product formation in Lactococcus lactis subsp. lactis IL1403 is presented. A library of strains with a modulated expression of PGE from 36 to 232% relative to wildtype level was constructed. Selected strains were studied with respect to growth, glycolytic flux and product formation in a chemically defined medium. On the basis of these data, flux control coefficients of PGE on the respective fluxes were calculated. At wildtype level, PGE was found to have no significant flux control on growth, glycolytic flux or product formation, but at 36% of PGE activity relative to wildtype, the flux control on the growth rate was estimated to be C(PGE)J(micro) approximately equal to 0.7, on the glycolytic flux C(PGE)J(g) approximately equal to 0.8, on lactate formation C(PGE)J(lactate) approximately equal to 1.3, on formate formation C(PGE)J(formate) approximately equal to 0.5 and on acetate formation C(PGE) J(acetate) approximately equal to 0.25. These flux control coefficients show that the metabolism of L. lactis subsp. lactis IL1403 becomes slightly more mixed acid at reduced PGE activities. Estimation of the relative turnover of PGE indicates that excess capacity of PGE in L. lactis IL1403 may be as low as twofold.

Catalysis↗

PubMed1986

Molecular cloning and nucleotide sequence of a full-length cDNA for human alpha enolase.

We previously purified a 48-kDa protein (p48) that specifically reacts with an antiserum directed against the 12 carboxyl-terminal amino acids of the c-myc gene product. Using an antiserum directed against the purified p48, we have cloned a cDNA from a human expression library. This cDNA hybrid-selects an mRNA that translates to a 48-kDa protein that specifically reacts with anti-p48 serum. We have isolated a full-length cDNA that encodes p48 and spans 1755 bases. The coding region is 1299 bases long; 94 bases are 5' noncoding and 359 bases are 3' noncoding. The cDNA encodes a 433 amino acid protein that is 67% homologous to yeast enolase and 94% homologous to the rat non-neuronal enolase. The purified protein has been shown to have enolase activity and has been identified to be of the alpha type by isoenzyme analysis. The transcriptional regulation of enolase expression in response to mitogenic stimulation of peripheral blood lymphocytes and in response to heat shock is also discussed.

Amino Acid Sequence↗

PubMed2006

Neurogenesis in the adult rat piriform cortex.

Multipotent neural precursors have been suggested to exist in many parts of the adult mammalian brain. In the present study, we characterized the neurogenic potential in the piriform cortex of adult rats. Proliferation rates as detected by 5'-bromodeoxyuridine-labeling proved to be low when compared with the major neurogenic brain regions (i.e. the hippocampus and the subventricular zone). 5'-Bromodeoxyuridine/NeuN-labeling in accordance with doublecortin, polysialylated neural cell adhesion molecule, and TUC-4-labeling indicated that neuronal differentiation of newborn cells occurs predominantly in layer II of the piriform cortex. Many of the cells exhibited a pyramidal cell morphology. The lack of 5'-bromodeoxyuridine/NeuN-labeled cells 12 weeks after 5'-bromodeoxyuridine administration argued against long-term survival of newborn neurons in the piriform cortex.

Animals↗

PubMed2005

Induction of angiogenesis by platelet-activating factor in the rat striatum.

Angiogenesis, the formation of new blood vessels, has been studied following injection of platelet-activating factor into the rat striatum. Immunohistochemical analysis for laminin showed that platelet-activating factor induced significant neovascularization in the striatum. A dose-dependent loss of striatal neurons accompanied this angiogenic activity. The platelet-activating factor-induced neovascularization and neurodegeneration were attenuated by the platelet-activating factor receptor antagonist, BN52021, or the inducible nitric oxide synthase inhibitor, aminoguanidine. Additionally, these agents significantly reduced levels of the angiogenic agent vascular endothelial growth factor, which was markedly enhanced in platelet-activating factor-injected striatum. Double immunofluorescence staining demonstrated that expression of vascular endothelial growth factor and inducible nitric oxide synthase were predominantly localized to microglia, suggesting that inflammatory responses mediated by activated microglia could contribute to platelet-activating factor-induced angiogenesis and neuronal loss.

Animals↗

PubMed1993

Neurocytoma/lipoma (neurolipocytoma) of the cerebellum.

We describe a unique tumour that was removed from the posterior fossa of a woman aged 50 years. It was characterized histologically by bland, oval cells with fibrillary cytoplasm and by small groups of lipocytes. Immunocytochemical studies demonstrated expression of synaptophysin, neuron specific enolase and PGP 9.5, but a few cells also expressed glial fibrillary acidic protein and desmin. The combination of neuroectodermal and mesodermal features in this tumour is discussed in relation to primitive neuroectodermal tumours and neurocytoma.

Cerebellar Neoplasms↗

PubMed2006

Identity of SMCT1 (SLC5A8) as a neuron-specific Na+-coupled transporter for active uptake of L-lactate and ketone bodies in the brain.

SMCT1 is a sodium-coupled (Na(+)-coupled) transporter for l-lactate and short-chain fatty acids. Here, we show that the ketone bodies, beta-d-hydroxybutyrate and acetoacetate, and the branched-chain ketoacid, alpha-ketoisocaproate, are also substrates for the transporter. The transport of these compounds via human SMCT1 is Na(+)-coupled and electrogenic. The Michaelis constant is 1.4 +/- 0.1 mm for beta-d-hydroxybutyrate, 0.21 +/- 0.04 mm for acetoacetate and 0.21 +/- 0.03 mm for alpha-ketoisocaproate. The Na(+) : substrate stoichiometry is 2 : 1. As l-lactate and ketone bodies constitute primary energy substrates for neurons, we investigated the expression pattern of this transporter in the brain. In situ hybridization studies demonstrate widespread expression of SMCT1 mRNA in mouse brain. Immunofluorescence analysis shows that SMCT1 protein is expressed exclusively in neurons. SMCT1 protein co-localizes with MCT2, a neuron-specific Na(+)-independent monocarboxylate transporter. In contrast, there was no overlap of signals for SMCT1 and MCT1, the latter being expressed only in non-neuronal cells. We also demonstrate the neuron-specific expression of SMCT1 in mixed cultures of rat cortical neurons and astrocytes. This represents the first report of an Na(+)-coupled transport system for a major group of energy substrates in neurons. These findings suggest that SMCT1 may play a critical role in the entry of l-lactate and ketone bodies into neurons by a process driven by an electrochemical Na(+) gradient and hence, contribute to the maintenance of the energy status and function of neurons.

Animals↗

PubMed1991

Abnormal gene expressions of stroma cells in patients with tuberous sclerosis.

The characteristics of stroma cells in tissues and the cloned cells, which derived from adenomata sebacea in the skin of patients with tuberous sclerosis, were investigated using histochemical, biochemical, flow cytofluorometric, electron microscopic, and immunofluorescent techniques, and the following results were obtained: 1. The stroma cells from adenoma sebaceum show a distinct pleomorphism. 2. They reveal glial cell-like gene expressions rather than fibroblastic ones in both tissue and cultured condition. 3. In culture their DNA histograms show abnormal patterns, suggesting the presence of nuclei that contain unequal quantities of DNA. 4. Some of these cells show distinct chromosome disarrangement in metaphase followed by abnormal divisions indicating the presence of a functional defect in the "centromere-microtubule-centriole" system. 5. It is characteristic that even in the cloned cells some changes spontaneously occur in the growth and differentiation of cells with an unstable frequency.

Adenoma↗

PubMedDate not supplied

Neuron-specific enolase, S-100 protein, myelin basic protein and lactate in CSF in dementia.

The pattern of injury of the specific cell structures of the central nervous system (CNS) is different in the various types of the dementia syndrome. We challenged the hypothesis that this could be reflected in specific patterns of brain-specific proteins in the cerebrospinal fluid (CSF). The neuron-specific enolase (NSE), S-100, myelin basic protein (MBP) and lactate levels were retrospectively analyzed in the CSF of 159 patients with various types of dementia. A previous study from our department demonstrated age-related reference values for the brain-specific proteins in the CSF. The present study affirmed the strikingly high NSE and S-100 values in the CSF of patients with autopsydiagnosed Creutzfeld-Jacob disease: NSE, S-100 and MBP levels in the CSF of patients with various other types of dementia, and controls, did not differ significantly. Therefore we concluded that a single determination of CSF concentrations of these brain-specific proteins were of little value in the differential diagnosis of the dementia syndrome. In the diagnosis of normal pressure hydrocephalus increased levels of CSF lactate may be helpful.

Aged↗

PubMed1989

Influence of epidermal growth factor on the maturation of fetal rat brain cells in aggregate culture. An immunocytochemical study.

Maturation of astrocytes, neurons, and oligodendrocytes was studied in serum-free aggregating cell cultures of fetal rat telencephalon by an immunocytochemical approach. Cell type-specific immunofluorescence staining was examined by using antibodies directed against glial fibrillary acidic protein (GFAP) and vimentin, two astroglial markers; neuron-specific enolase (NSE) and neurofilament (NF), two neuronal markers, and galactocerebroside (GC), an oligodendroglial marker. It was found that the cellular maturation in aggregates is characterized by distinct developmental increases in immunoreactivity for GFAP, vimentin, NSE, NF, and GC, and by a subsequent decrease of vimentin-positive structures in more differentiated cultures. These findings are in agreement with observations in vivo, and they corroborate previous biochemical studies of this histotypic culture system. Treatment of very immature cultures with a low dose of epidermal growth factor (EGF, 5 ng/ml) enhanced the developmental increase in GFAP, NSE, NF and GC immunoreactivity, suggesting an acceleration of neuronal and glial maturation. In addition, EGF was found to alter the cellular organization within the aggregates, presumably by influencing cell migration.

Animals↗

PubMed1993

Neuron-specific enolase and glial fibrillary acidic protein in vitamin-A-induced mouse myeloschisis: an immunohistochemical study.

In an effort to establish the appropriate timing of myeloschisis repair, changes in the exposed neural tissue were studied during fetal development. Neuron-specific enolase (NSE) and glial fibrillary acidic protein (GFAP) were examined immunohistochemically in mice with vitamin-A-induced myeloschisis. As in the normally developing lumbosacral spinal cord, NSE was already expressed in the cytoplasm of neurons in the basal plate of the neural plaque in 16-day-old embryos. GFAP became positive at day 17 both in normal embryos and at the outer border of the plaques in dysraphic embryos. Expression of both NSE and GFAP in normal controls was unchanged in intensity and localization during later fetal development. In contrast, the expression of GFAP increased during later development in the neural plaque of dysraphic animals and suggests a progressive gliosis of tissue with the passage of time. The expression of NSE in the plaque did not change during this time. These results suggest that the neural plaque retains intact neurons in the face of progressive gliosis. Moreover, the results suggest that repair of the myeloschisis should start before irreversible changes are established by progressive gliosis.

Animals↗

PubMed1991

Morphologic and immunohistochemical characterization of Leydig cell tumor variants in Wistar rats.

During a routine long-term drug safety study, lasting approximately 2 1/2 yr, male Wistar rats, treated with a prolactin-inhibiting compound, developed an excess of Leydig cell tumors (LCTs). Most tumors were typical for the rat but a small number showed an unusual variation and some appeared malignant. The variation consisted of glandular and/or tubular structures within the tumor mass which occasionally anastomosed and contained an eosinophilic periodic-acid Schiff (PAS) positive material. In a few of these variants, malignant features such as cellular atypia, capsular, and lymphatic invasion and necrosis were seen. No metastases were detected. Detailed morphological and immunohistochemical investigations were conducted in order to establish the cell of origin of these variants. Glandular/tubular structures were found to stain with varying intensity for vimentin and cytokeratin, but were always negative for beta-tubulin. The results indicated that the cell of origin of these LCT variants was indeed the Leydig cell and that glandular and/or tubular structures within LCTs represented a form of Leydig cell metaplasia.

Animals↗