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1.
BMC Cancer ; 21(1): 1010, 2021 Sep 09.
Article in English | MEDLINE | ID: mdl-34503460

ABSTRACT

BACKGROUND: OptimalTTF-2 is a randomized, comparative, multi-center, investigator-initiated, interventional study aiming to test skull remodeling surgery in combination with Tumor Treating Fields therapy (TTFields) and best physicians choice medical oncological therapy for first recurrence in glioblastoma patients. OptimalTTF-2 is a phase 2 trial initiated in November 2020. Skull remodeling surgery consists of five burrholes, each 15 mm in diameter, directly over the tumor resection cavity. Preclinical research indicates that this procedure enhances the effect of Tumor Treating Fields considerably. We recently concluded a phase 1 safety/feasibility trial that indicated improved overall survival and no additional toxicity. This phase 2 trial aims to validate the efficacy of the proposed intervention. METHODS: The trial is designed as a comparative, 1:1 randomized, minimax two-stage phase 2 with an expected 70 patients to a maximum sample size of 84 patients. After 12-months follow-up of the first 52 patients, an interim futility analysis will be performed. The two trial arms will consist of either a) TTFields therapy combined with best physicians choice oncological treatment (control arm) or b) skull remodeling surgery, TTFields therapy and best practice oncology (interventional arm). Major eligibility criteria include age ≥ 18 years, 1st recurrence of supratentorial glioblastoma, Karnofsky performance score ≥ 70, focal tumor, and lack of significant co-morbidity. Study design aims to detect a 20% increase in overall survival after 12 months (OS12), assuming OS12 = 40% in the control group and OS12 = 60% in the intervention group. Secondary endpoints include hazard rate ratio of overall survival and progression-free survival, objective tumor response rate, quality of life, KPS, steroid dose, and toxicity. Toxicity, objective tumor response rate, and QoL will be assessed every 3rd month. Endpoint data will be collected at the end of the trial, including the occurrence of suspected unexpected serious adverse reactions (SUSARs), unacceptable serious adverse events (SAEs), withdrawal of consent, or loss-to-follow-up. DISCUSSION: New treatment modalities are highly needed for first recurrence glioblastoma. Our proposed treatment modality of skull remodeling surgery, Tumor Treating Fields, and best practice medical oncological therapy may increase overall survival significantly. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT0422399 , registered 13. January 2020.


Subject(s)
Brain Neoplasms/surgery , Glioblastoma/surgery , Neoplasm Recurrence, Local/surgery , Osteotomy/methods , Skull/surgery , Adult , Follow-Up Studies , Glioblastoma/mortality , Humans , Karnofsky Performance Status , Neoplasm Recurrence, Local/mortality , Progression-Free Survival , Prospective Studies , Quality of Life , Time Factors , Transducers
2.
Neuropathol Appl Neurobiol ; 47(1): 108-126, 2021 02.
Article in English | MEDLINE | ID: mdl-32696543

ABSTRACT

AIMS: We aimed to reclassify a population-based cohort of 529 adult glioma patients to evaluate the prognostic impact of the 2016 World Health Organization (WHO) central nervous system tumour classification. Moreover, we evaluated the feasibility of gene panel next-generation sequencing (NGS) in daily diagnostics of 225 prospective glioma patients. METHODS: The retrospective cohort was reclassified according to WHO 2016 criteria by immunohistochemistry for IDH-R132H, fluorescence in situ hybridization for 1p/19q-codeletion and gene panel NGS. All tumours of the prospective cohort were subjected to NGS analysis up-front. RESULTS: The entire population-based cohort was successfully reclassified according to WHO 2016 criteria. NGS results were obtained for 98% of the prospective patients. Survival analyses in the population-based cohort confirmed three major prognostic subgroups, that is, isocitrate dehydrogenase (IDH)-mutant and 1p/19q-codeleted oligodendrogliomas, IDH-mutant astrocytomas and IDH-wildtype glioblastomas. The distinction between WHO grade II and III was prognostic in patients with IDH-mutant astrocytoma. The survival of patients with IDH-wildtype diffuse astrocytomas carrying TERT promoter mutation and/or EGFR amplification overlapped with the poor survival of IDH-wildtype glioblastoma patients. CONCLUSIONS: Gene panel NGS proved feasible in daily diagnostics. In addition, our study confirms the prognostic role of glioma classification according to WHO 2016 in a large population-based cohort. Molecular features of glioblastoma in IDH-wildtype diffuse glioma were linked to poor survival corresponding to IDH-wildtype glioblastoma patients. The distinction between WHO grade II and III retained prognostic significance in patients with IDH-mutant diffuse astrocytic gliomas.


Subject(s)
Biomarkers, Tumor/genetics , Brain Neoplasms/diagnosis , Glioma/pathology , High-Throughput Nucleotide Sequencing , Adolescent , Adult , Aged , Aged, 80 and over , Astrocytoma/diagnosis , Astrocytoma/genetics , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Female , Glioblastoma/diagnosis , Glioblastoma/genetics , Glioma/diagnosis , Glioma/genetics , Humans , Isocitrate Dehydrogenase/genetics , Male , Middle Aged , Mutation/genetics , Prognosis , Telomerase/genetics , Young Adult
4.
Acta Neurochir (Wien) ; 162(12): 3001-3004, 2020 12.
Article in English | MEDLINE | ID: mdl-32240377

ABSTRACT

A lobular capillary hemangioma, previously known as a pyogenic granuloma, is a benign vascular lesion of the skin or mucous membrane. We report a case of capillary hemangioma of lobular subtype in the calvarium of a 28-year-old pregnant woman which presented as a sore and rapidly growing bulge over the left fronto-parietal region. Magnetic resonance imaging of the brain and skull showed an expansive tumor with brain displacement, skull erosion, and scalp infiltration. The tumor was surgically removed, and histopathological examination showed a capillary hemangioma of lobular subtype. To the best of our knowledge, this is the first report of a lobular capillary hemangioma in the calvarium, and it represents a rarity to be considered among the many other differential diagnoses for neurosurgical lesions involving the skull, especially in pregnant women.


Subject(s)
Bone Diseases/surgery , Granuloma, Pyogenic/surgery , Pregnancy Complications/surgery , Skull/surgery , Adult , Bone Diseases/diagnosis , Bone Diseases/pathology , Diagnosis, Differential , Female , Granuloma, Pyogenic/diagnosis , Granuloma, Pyogenic/pathology , Humans , Magnetic Resonance Imaging , Pregnancy , Pregnancy Complications/diagnosis , Pregnancy Complications/pathology , Pregnant Women , Skull/pathology
5.
Neurocrit Care ; 29(3): 496-503, 2018 Dec.
Article in English | MEDLINE | ID: mdl-29508265

ABSTRACT

BACKGROUND: Cerebral mitochondrial dysfunction is prominent in the pathophysiology of severe bacterial meningitis. In the present study, we hypothesize that the metabolic changes seen after intracisternal lipopolysaccharide (LPS) injection in a piglet model of meningitis is compatible with mitochondrial dysfunction and resembles the metabolic patterns seen in patients with bacterial meningitis. METHODS: Eight pigs received LPS injection in cisterna magna, and four pigs received NaCl in cisterna magna as a control. Biochemical variables related to energy metabolism were monitored by intracerebral microdialysis technique and included interstitial glucose, lactate, pyruvate, glutamate, and glycerol. The intracranial pressure (ICP) and brain tissue oxygen tension (PbtO2) were also monitored along with physiological variables including mean arterial pressure, blood glucose, lactate, and partial pressure of O2 and CO2. Pigs were monitored for 60 min at baseline and 240 min after LPS/NaCl injection. RESULTS: After LPS injection, a significant increase in cerebral lactate/pyruvate ratio (LPR) compared to control group was registered (p = 0.01). This increase was due to a significant increased lactate with stable and normal values of pyruvate. No significant change in PbtO2 or ICP was registered. No changes in physiological variables were observed. CONCLUSIONS: The metabolic changes after intracisternal LPS injection is compatible with disturbance in the oxidative metabolism and partly due to mitochondrial dysfunction with increasing cerebral LPR due to increased lactate and normal pyruvate, PbtO2, and ICP. The metabolic pattern resembles the one observed in patients with bacterial meningitis. Metabolic monitoring in these patients is feasible to monitor for cerebral metabolic derangements otherwise missed by conventional intensive care monitoring.


Subject(s)
Cerebrum/metabolism , Lactic Acid/metabolism , Lipopolysaccharides/pharmacology , Meningitis, Bacterial/metabolism , Mitochondrial Diseases/metabolism , Pyruvic Acid/metabolism , Animals , Disease Models, Animal , Female , Lipopolysaccharides/administration & dosage , Microdialysis , Neurophysiological Monitoring , Swine
6.
Eur J Clin Microbiol Infect Dis ; 36(10): 1975-1980, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28578477

ABSTRACT

It is well described that patients with pulmonary arteriovenous malformations (PAVMs) and Hereditary Hemorrhagic Telangiectasia (HHT) have an increased risk of cerebral abscess (CA). However, as both CA and HHT are rare, the proportion of patients with CA who are diagnosed with HHT has not been previously described. A retrospective study was carried out of all patients treated surgically for CA between January 1995 and September 2014 at the Department of Neurosurgery, Odense University Hospital. The cases were then cross-referenced with the Danish HHT database. Eighty patients aged 5-79 years were included. The incidence of CA was 0.33/100,000/year. Two patients (2.5%) were registered as having HHT. Bacterial pathogens were identified in 70% of all cases, most frequently streptococci species (46.3%). The most common predisposing condition was odontogenic infection (20%), followed by post-operative infection (13.8%) and post-trauma (6.3%). Patients undergoing a full diagnostic program to determine predisposing conditions causing CA increased over the 20-year period from 11.8% to 65.2%. The 3-month and 1-year mortality rates were 7.5% and 11.25%, respectively. There is an overrepresentation of HHT patients in a cohort of patients with CA, and HHT should be investigated as the cause of the CA if no other apparent cause can be identified.


Subject(s)
Brain Abscess/epidemiology , Telangiectasia, Hereditary Hemorrhagic/complications , Adolescent , Adult , Aged , Bacteria/classification , Bacteria/isolation & purification , Brain Abscess/microbiology , Brain Abscess/surgery , Child , Child, Preschool , Denmark/epidemiology , Female , Hospitals , Humans , Incidence , Male , Middle Aged , Prevalence , Retrospective Studies , Young Adult
7.
Acta Physiol (Oxf) ; 219(3): 640-651, 2017 03.
Article in English | MEDLINE | ID: mdl-27273014

ABSTRACT

AIM: Calcium channel blockers are widely used in cardiovascular diseases. Besides L-type channels, T- and P/Q-type calcium channels are involved in the contraction of human renal blood vessels. It was hypothesized that T- and P/Q-type channels are involved in the contraction of human brain and mammary blood vessels. METHODS: Internal mammary arteries from bypass surgery patients and cerebral arterioles from patients with brain tumours with and without hypertension were tested in a myograph and perfusion set-up. PCR and immunohistochemistry were performed on isolated blood vessels. RESULTS: The P/Q-type antagonist ω-agatoxin IVA (10-8  mol L-1 ) and the T-type calcium blocker mibefradil (10-7  mol L-1 ) inhibited KCl depolarization-induced contraction in mammary arteries from hypertensive patients with no effect on blood vessels from normotensive patients. ω-Agatoxin IVA decreased contraction in cerebral arterioles from hypertensive patients. L-type blocker nifedipine abolished the contraction in mammary arteries. PCR analysis showed expression of P/Q-type (Cav 2.1), T-type (Cav 3.1 and Cav 3.2) and L-type (Cav 1.2) calcium channels in mammary and cerebral arteries. Immunohistochemical labelling of mammary and cerebral arteries revealed the presence of Cav 2.1 in endothelial and smooth muscle cells. Cav 3.1 was also detected in mammary arteries. CONCLUSION: P/Q- and T-type Cav are present in human internal mammary arteries and in cerebral penetrating arterioles. P/Q- and T-type calcium channels are involved in the contraction of mammary arteries from hypertensive patients but not from normotensive patients. Furthermore, in cerebral arterioles P/Q-type channels importance was restricted to hypertensive patients might lead to that T- and P/Q-type channels could be a new target in hypertensive patients.


Subject(s)
Calcium Channels/metabolism , Cerebral Arteries/metabolism , Hypertension/metabolism , Mammary Arteries/metabolism , Vasoconstriction/physiology , Aged , Calcium Channel Blockers/pharmacology , Calcium Channels/drug effects , Cerebral Arteries/drug effects , Female , Humans , Immunohistochemistry , Male , Mammary Arteries/drug effects , Middle Aged , Organ Culture Techniques , Patch-Clamp Techniques , Polymerase Chain Reaction , Vasoconstriction/drug effects
8.
Eur J Neurosci ; 27(8): 2089-102, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18412629

ABSTRACT

The neuroprotective effect of neuropeptide Y (NPY) receptor activation was investigated in organotypic mouse hippocampal slice cultures exposed to the glutamate receptor agonist alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA). Exposure of 2-week-old slice cultures, derived from 7-day-old C57BL/6 mice, to 8 microm AMPA, for 24 h, induced degeneration of CA1 and CA3 pyramidal cells, as measured by cellular uptake of propidium iodide (PI). A significant neuroprotection, with a reduction of PI uptake in CA1 and CA3 pyramidal cell layers, was observed after incubation with a Y(2) receptor agonist [NPY(13-36), 300 nm]. This effect was sensitive to the presence of the selective Y(2) receptor antagonist (BIIE0246, 1 microm), but was not affected by addition of TrkB-Fc or by a neutralizing antibody against brain-derived neurotrophic factor (BDNF). Moreover, addition of a Y(1) receptor antagonist (BIBP3226, 1 microm) or a NPY-neutralizing antibody helped to disclose a neuroprotective role of endogenous NPY in CA1 region. Cultures exposed to 8 microm AMPA for 24 h, displayed, as measured by an enzyme-linked immunosorbent assay, a significant increase in BDNF. In such cultures there was an up-regulation of neuronal TrkB immunoreactivity, as well as the presence of BDNF-immunoreactive microglial cells at sites of injury. Thus, an increase of AMPA-receptor mediated neurodegeneration, in the mouse hippocampus, was prevented by neuroprotective pathways activated by NPY receptors (Y(1) and Y(2)), which can be affected by BDNF released by microglia and neurons.


Subject(s)
Brain-Derived Neurotrophic Factor/metabolism , Microglia/metabolism , Neurons/metabolism , Neuropeptide Y/metabolism , Receptors, Neuropeptide Y/metabolism , Animals , Enzyme-Linked Immunosorbent Assay , Hippocampus/metabolism , Immunohistochemistry , Mice , Mice, Inbred C57BL , Organ Culture Techniques , Receptors, AMPA/metabolism , Receptors, Neuropeptide Y/antagonists & inhibitors , Reverse Transcriptase Polymerase Chain Reaction
9.
Neuroscience ; 126(3): 665-76, 2004.
Article in English | MEDLINE | ID: mdl-15183516

ABSTRACT

Activity-dependent brain-derived neurotrophic factor (BDNF) expression is Ca2+-dependent, yet little is known about the Ca2+ channel contributions that might direct selective expression of the multiple BDNF transcripts. Here, effects of pilocarpine-induced seizure activity on total BDNF expression and on the individual sensitivity of BDNF transcripts to glutamate receptor and Ca2+ channel blockers were evaluated using hippocampal slice cultures and in situ hybridization of transcript-specific cRNA probes directed against mRNAs for the four 5' exons (I-IV) of the BDNF gene. mRNAs for nerve growth factor (NGF) and tyrosine kinase B (trkB) also were studied. Pilocarpine (5 mM) induced a dose- and time-dependent increase in total BDNF (exon V) mRNA expression in the dentate granule cells and CA3-CA1 pyramidal cells with maximal effects at 6 and 24 h, respectively. Increases were blocked by co-treatment with the alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid/kainate 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX: 25 microM) and the N-methyl-d-aspartic acid receptor antagonist 2-amino-5-phosphonovaleric acid (APV; 25 microM), whereas the L-type voltage sensitive Ca2+ channel blocker nifedipine (20 microM) was without detectable effect. Maximal NGF and trkB mRNA expression was induced by pilocarpine at 4 and 12 h, respectively. For the individual BDNF transcripts, APV blocked pilocarpine-induced increases in transcript II, whereas nifedipine blocked increases in transcripts I and III. Transcript IV levels were not altered by treatment. These results indicate that transcript II makes the greatest contribution to pilocarpine effects on total BDNF mRNA content in this model and provides evidence for regional and Ca2+ channel-specific differences in activity-dependent regulation of the different BDNF transcripts in hippocampus.


Subject(s)
Brain-Derived Neurotrophic Factor/genetics , Calcium/metabolism , Pilocarpine/pharmacology , Seizures/physiopathology , Alternative Splicing , Animals , Brain-Derived Neurotrophic Factor/biosynthesis , Brain-Derived Neurotrophic Factor/drug effects , Calcium Channel Blockers/pharmacology , Dose-Response Relationship, Drug , Excitatory Amino Acid Antagonists/pharmacology , Gene Expression Regulation , Hippocampus/drug effects , Hippocampus/metabolism , In Situ Hybridization , Muscarinic Agonists/pharmacology , Nerve Growth Factor/drug effects , Nerve Growth Factor/metabolism , Organ Culture Techniques , RNA, Messenger/analysis , Rats , Receptor, trkB/drug effects , Receptor, trkB/metabolism , Seizures/chemically induced , Time Factors
10.
J Biol Chem ; 276(36): 33547-53, 2001 Sep 07.
Article in English | MEDLINE | ID: mdl-11435437

ABSTRACT

In plants a group of proteins termed nonspecific lipid transfer proteins are found. These proteins bind and catalyze transfer of lipids in vitro, but their in vivo function is unknown. They have been suggested to be involved in different aspects of plant physiology and cell biology, including the formation of cutin and involvement in stress and pathogen responses, but there is yet no direct demonstration of an in vivo function. We have found and characterized a novel post-translational modification of the barley nonspecific lipid transfer protein, LTP1. The protein-modification bond is of a new type in which an aspartic acid in LTP1 is bound to the modification through what most likely is an ester bond. The chemical structure of the modification has been characterized by means of two-dimensional homo- and heteronuclear nuclear magnetic resonance spectroscopy as well as mass spectrometry and is found to be lipid-like in nature. The modification does not resemble any standard lipid post-translational modification but is similar to a compound with known antimicrobial activity.


Subject(s)
Hordeum/chemistry , Lipids/chemistry , Plant Proteins/chemistry , Protein Tyrosine Phosphatases/chemistry , Saccharomyces cerevisiae Proteins , Amino Acids/chemistry , Aspartic Acid/chemistry , Carbohydrates/chemistry , Carboxylic Acids/chemistry , Esters/chemistry , Glycosylation , Hydrogen-Ion Concentration , Kinetics , Magnetic Resonance Spectroscopy , Mass Spectrometry , Models, Chemical , Models, Molecular , Peptides/chemistry , Protein Processing, Post-Translational , Temperature , Time Factors , Trypsin/chemistry
11.
J Laryngol Otol ; 115(6): 504-6, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11429081

ABSTRACT

Calcium pyrophosphate dihydrate crystal deposition disease, exhibits several clinical manifestations, from absence of symptoms to severely destructive arthropathy or conditions simulating neoplasm, which is frequently related to the temporomandibular joint. Fifteen of the 31 reported cases of tophaceous pseudogout were found in the head and neck region. A patient presented with a parotid swelling, which initially was suspected to be malignant because of the following findings: radiodensity, progression into the joint, osseous destruction of the major ala of the sphenoid and a fine needle aspirate with crystals, osteoblasts, megakaryocytes and irregular cells of varying size. At surgery there was found a tumour consisting of a white, firm gritty material. It progressed to the skull base where material had to be left, because of the presence of the nerves and vessels. A frozen specimen was reported to be benign. Histological examination showed inflammatory cells, macrophages, a chondroid material with embedded metaplastic chondroid cells and giant cells of foreign body type. Crystal examination of X-ray diffraction revealed calcium pyrophosphate dihydrate.


Subject(s)
Chondrocalcinosis/diagnosis , Parotid Diseases/diagnosis , Diagnosis, Differential , Female , Humans , Middle Aged , Parotid Neoplasms/diagnosis , Tomography, X-Ray Computed
12.
Ugeskr Laeger ; 162(25): 3616-7, 2000 Jun 19.
Article in Danish | MEDLINE | ID: mdl-11016289

ABSTRACT

Tophaceous pseudogout is a rare form of calcium pyrophosphate dihydrate (CPPD) crystal deposition disease. Half of the 31 reported cases of tophaceous pseudogout are in the head and neck region. This patient presented with a parotid tumour, that was initially suspected to be malignant based on radiology and cytology. Operation disclosed a tumour progressing to the base of the skull, histological examination showed inflammatory cells, macrophages, metaplastic chondroid cells and giant cells of foreign-body-type. X-ray diffraction revealed two crystal forms of CPPD.


Subject(s)
Chondrocalcinosis/diagnosis , Parotid Neoplasms/diagnosis , Chondrocalcinosis/diagnostic imaging , Chondrocalcinosis/pathology , Diagnosis, Differential , Female , Humans , Middle Aged , Parotid Neoplasms/diagnostic imaging , Parotid Neoplasms/pathology , Tomography, X-Ray Computed
13.
J Mol Biol ; 301(5): 1307-14, 2000 Sep 01.
Article in English | MEDLINE | ID: mdl-10966822

ABSTRACT

A burst phase in the early folding of the four-helix two-state folder protein acyl-coenzyme A binding protein (ACBP) has been detected using quenched-flow in combination with site-specific NMR-detected hydrogen exchange. Several of the burst phase structures coincide with a structure consisting of eight conserved hydrophobic residues at the interface between the two N and C-terminal helices. Previous mutation studies have shown that the formation of this structure is rate limiting for the final folding of ACBP. The burst phase structures observed in ACBP are different from the previously reported collapsed types of burst phase intermediates observed in the folding of other proteins.


Subject(s)
Carrier Proteins/chemistry , Carrier Proteins/metabolism , Protein Folding , Amides/chemistry , Amides/metabolism , Animals , Cattle , Conserved Sequence , Diazepam Binding Inhibitor , Hydrogen/metabolism , Hydrogen Bonding , Hydrogen-Ion Concentration , Isoleucine/metabolism , Kinetics , Magnetic Resonance Spectroscopy , Models, Molecular , Protein Structure, Secondary , Protons , Serine/metabolism
14.
Epilepsia ; 41(S1): 48-51, 2000.
Article in English | MEDLINE | ID: mdl-10768301

ABSTRACT

PURPOSE: This study was undertaken to test the hypothesis that topiramate (TPM) exerts a negative modulatory effect on some types of alpha-amino-3-hydroxy-5-methylisoxazole-4-proprionic acid (AMPA)/kainate receptors by binding to the site at which protein kinase A (PKA) phosphorylates the receptor-channel complex. METHODS: The effect of TPM on kainate- or domoate-induced [14C]guanidinium ion flux through iGluR6 channels expressed in baby hamster kidney (BHK) cells was evaluated. Because the hypothesis predicts that TPM will bind only in the dephosphorylated state, a variety of experimental conditions were used to either promote or impede the phosphorylation of the receptor-channel complex. These included the use of dibutyryl cyclic adenosine monophosphate (cAMP) and forskolin to activate PKA, H-9 and H-89 to inhibit PKA, and okadaic acid to inhibit protein phosphatases. RESULTS: Kainate (1 microM) induced a gradual accumulation of [14C]guanidinium into the cells that plateaued approximately 30 min after initiation of the reaction, whereas domoate (0.1 microM) caused a rapid accumulation into the cells that peaked within 5 min; thereafter, the amount of [14C]guanidinium in the cells declined gradually. Topiramate, at 0.1 and 100 microM, did not significantly affect the [14C]guanidinium accumulation under any of the experimental conditions used. CONCLUSIONS: The results of this study are not consistent with the hypothesis tested. However, the results must be interpreted cautiously because iGluR6 receptors expressed in the BHK cells and the functional state of proteins that regulate AMPA/receptors (e.g., PSD-95) may not be sufficiently similar to the receptors and functional state in neurons to serve as a true test of the hypothesis.


Subject(s)
Anticonvulsants/pharmacokinetics , Cyclic AMP-Dependent Protein Kinases/metabolism , Fructose/analogs & derivatives , Guanidine/metabolism , Receptors, Glutamate/metabolism , Animals , Anticonvulsants/pharmacology , Carbon Radioisotopes , Cell Line , Colforsin/pharmacology , Cricetinae , Cyclic AMP/pharmacology , Fructose/pharmacokinetics , Fructose/pharmacology , Kainic Acid/analogs & derivatives , Kainic Acid/pharmacology , Kidney , Phosphorylation , Receptors, AMPA/drug effects , Receptors, AMPA/metabolism , Receptors, Glutamate/drug effects , Receptors, Kainic Acid/drug effects , Receptors, Kainic Acid/metabolism , Scintillation Counting/instrumentation , Topiramate , Transfection
15.
Int J Dev Neurosci ; 18(2-3): 221-35, 2000.
Article in English | MEDLINE | ID: mdl-10715577

ABSTRACT

The regulation of oligodendrocyte gene expression and myelination in vivo in the normal and injured adult CNS is still poorly understood. We have analyzed the effects of axotomy-induced axonal sprouting and microglial activation, on oligodendrocyte myelin basic protein (MBP) gene expression from 2 to 35 days after transection of the entorhino-hippocampal perforant path axonal projection. In situ hybridization analysis showed that anterograde axonal and terminal degeneration lead to upregulated oligodendrocyte MBP mRNA expression starting between day 2 and day 4, in (1) the deep part of stratum radiatum of CA3 and the dentate hilus, which display axonal sprouting but no degenerative changes or microglial activation, and (2) the outer part of the molecular layer of the fascia dentata, and in stratum moleculare of CA3 and stratum lacunosum-moleculare of CA1, areas that display dense anterograde axonal and terminal degeneration, myelin degenerative changes, microglial activation and axotomi-induced axonal sprouting. Oligodendrocyte MBP mRNA expression reached maximum in both these areas at day 7. MBP gene transcription remained constant in stratum radiatum, stratum pyramidale and stratum oriens of CA1, areas that were unaffected by perforant path transection. These results provide strong evidence that oligodendrocyte MBP gene expression can be regulated by axonal sprouting independently of microglial activation in the injured adult CNS.


Subject(s)
Axons/enzymology , Hippocampus/physiology , Myelin Basic Protein/genetics , Nerve Regeneration/physiology , Wallerian Degeneration/physiopathology , Acetylcholinesterase/analysis , Animals , Axons/chemistry , Coloring Agents , Denervation , Entorhinal Cortex/chemistry , Entorhinal Cortex/cytology , Entorhinal Cortex/physiology , Gene Expression/physiology , Hippocampus/chemistry , Hippocampus/cytology , Male , Mice , Mice, Inbred C57BL , Microglia/physiology , Neuronal Plasticity/physiology , Oligodendroglia/physiology , Perforant Pathway/chemistry , Perforant Pathway/cytology , Perforant Pathway/physiology , RNA, Messenger/analysis , Silver Staining , Tolonium Chloride
16.
Exp Brain Res ; 135(3): 319-30, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11146810

ABSTRACT

Heparin affin regulatory peptide (HARP), also known as pleiotrophin or heparin-binding growth-associated molecule, is a developmentally regulated extracellular matrix protein that induces cell proliferation and promotes neurite outgrowth in vitro as well as pre- and postsynaptic developmental differentiation in vivo. Here we have investigated the expression of HARP mRNA and protein in the perforant path lesioned C57B1/6 mouse hippocampal formation from 1 to 35 days after surgery. This type of lesion induces a dense anterograde and terminal axonal degeneration, activation of glial cells, and reactive axonal sprouting within the perforant path zones of the fascia dentata and hippocampus as well as axotomy-induced retrograde neuronal degeneration in the entorhinal cortex. Analysis of sham- and unoperated control mice showed that HARP mRNA is expressed in neurons and white and gray matter glial cells as well as vascular and pial cells throughout the normal, adult brain. Lesioning induced high levels of HARP mRNA in astroglial-like cells in the denervated zones of fascia dentata and hippocampus as soon as day 2 postlesion. This expression reached maximum at day 4, and declined toward normal at day 7-14. Combined HARP in situ hybridization and glial fibrillary acidic protein (GFAP) immunohistochemical staining and double immunofluorescent stainings for GFAP and HARP at day 4 postlesion showed colocalization of HARP mRNA and protein to hypertrophic GFAP-immunopositive astrocytes in the denervated areas. Finally, the axotomized entorhinal layer II neurons, which expressed high levels of HARP mRNA in the normal brain, exhibited a marked decline in hybridization signal after axotomy. The induction of high levels of HARP mRNA and protein in astrocytes in the denervated areas of fascia dentata and hippocampus is of particular interest as astrocytes and astrocyte-derived factors are known to be implicated in axonal growth and regeneration and in rescuing injured neurons.


Subject(s)
Carrier Proteins/biosynthesis , Cytokines/biosynthesis , Hippocampus/metabolism , Nerve Growth Factors/biosynthesis , Perforant Pathway/physiology , Animals , Coloring Agents , Fluorescent Dyes , Glial Fibrillary Acidic Protein/metabolism , Immunohistochemistry , In Situ Hybridization , Male , Mice , Mice, Inbred C57BL , Nerve Degeneration , Nerve Tissue Proteins/biosynthesis , Paraffin Embedding , RNA, Messenger/biosynthesis
17.
Curr Opin Drug Discov Devel ; 3(5): 605-9, 2000 Sep.
Article in English | MEDLINE | ID: mdl-19649888

ABSTRACT

During the past year, the understanding of the structure and function of neural cell adhesion has advanced considerably. The three-dimensional structures of several of the individual modules of the neural cell adhesion molecule (NCAM) have been determined, as well as the structure of the complex between two identical fragments of the NCAM. Also during the past year, a link between homophilic cell adhesion and several signal transduction pathways has been proposed, connecting the event of cell surface adhesion to cellular responses such as neurite outgrowth. Finally, the stimulation of neurite outgrowth by an agent that binds to the first module of NCAM has been described.

18.
Biochim Biophys Acta ; 1441(2-3): 150-61, 1999 Nov 23.
Article in English | MEDLINE | ID: mdl-10570243

ABSTRACT

Acyl-coenzyme A binding proteins are known from a large group of eukaryote species and to bind a long chain length acyl-CoA ester with very high affinity. Detailed biochemical mapping of ligand binding properties has been obtained as well as in-depth structural studies on the bovine apo-protein and of the complex with palmitoyl-CoA using NMR spectroscopy. In the four alpha-helix bundle structure, a set of 21 highly conserved residues present in more that 90% of all known sequences of acyl-coenzyme A binding proteins constitutes three separate mini-cores. These residues are predominantly located at the helix-helix interfaces. From studies of a large set of mutant proteins the role of the conserved residues has been related to structure, function, folding and stability.


Subject(s)
Carrier Proteins , Amino Acid Sequence , Animals , Carrier Proteins/chemistry , Carrier Proteins/genetics , Carrier Proteins/metabolism , Diazepam Binding Inhibitor , Humans , Models, Molecular , Molecular Sequence Data , Molecular Structure , Mutagenesis , Sequence Alignment
19.
Nat Biotechnol ; 17(10): 1000-5, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10504702

ABSTRACT

The neural cell adhesion molecule (NCAM) plays a key role in neural development, regeneration, and learning. In this study, we identified a synthetic peptide-ligand of the NCAM Ig1 module by combinatorial chemistry and showed it could modulate NCAM-mediated cell adhesion and signal transduction with high potency. In cultures of dissociated neurons, this peptide, termed C3, stimulated neurite outgrowth by activating a signaling pathway identical to that activated by homophilic NCAM binding. A similar effect was shown for the NCAM Ig2 module, the endogenous ligand of NCAM Ig1. By nuclear magnetic resonance spectroscopy, the C3 binding site in the NCAM Ig1 module was mapped and shown to be different from the binding site of the NCAM Ig2 module. The C3 peptide may prove useful as a lead in development of therapies for neurodegenerative disorders, and the C3 binding site of NCAM Ig1 may represent a target for discovery of nonpeptide drugs.


Subject(s)
Cell Adhesion Molecules, Neuronal/metabolism , Combinatorial Chemistry Techniques , Neurites/metabolism , Peptide Library , Peptides/metabolism , Amino Acid Sequence , Consensus Sequence , Immunoglobulins/metabolism , Ligands , Magnetic Resonance Spectroscopy , Molecular Sequence Data , Signal Transduction , Surface Plasmon Resonance
20.
J Magn Reson ; 140(1): 259-63, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10479570

ABSTRACT

A set of three improved two-dimensional (2D) NMR methods for measuring one-bond (15)N-(1)H coupling constants in the protein backbone is presented. They are tailored to suit the size of the TROSY effect, i.e., the degree of interference between dipolar and chemical shift anisotropy relaxation mechanisms. The methods edit 2D spectra into two separate subspectra corresponding to the two possible spin states of the coupling partner. Cross talk between the two subspectra is a second order effect in the difference between the actual coupling constants and the one used in setting the pertinent delays of the pulse sequences. This relatively high degree of editing accuracy makes the methods useful for applications to molecules subjected to weak alignment where the one-bond coupling constants are linear combinations of a scalar J and a residual dipolar contribution containing important structural information. A demonstration of the new methods is shown for the (15)N-labeled protein chymotrypsin inhibitor 2 in a lipid bicelle mixture.


Subject(s)
Magnetic Resonance Spectroscopy/methods , Phospholipids/chemistry , Hydrogen/chemistry , Hydrogen Bonding , Nitrogen/chemistry , Nitrogen Isotopes
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