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1.
RSC Adv ; 12(48): 30860-30870, 2022 Oct 27.
Article in English | MEDLINE | ID: mdl-36349035

ABSTRACT

Photodeposition is a specific method for depositing metallic co-catalysts onto photocatalysts and was applied for immobilizing platinum nanoparticles onto cellulose, a photocatalytically inactive biopolymer. The obtained Pt@cellulose catalysts show narrow and well-dispersed nanoparticles with average sizes between 2 and 5 nm, whereby loading, size and distribution depend on the preparation conditions. The catalysts were investigated for the hydrogenation of para-nitrophenol via transfer hydrogenation using sodium borohydride as the hydrogen source, and the reaction rate constant was determined using the pseudo-first-order reaction rate law. The Pt@cellulose catalysts are catalytically active with rate constant values k from 0.09 × 10-3 to 0.43 × 10-3 min-1, which were higher than the rate constant of a commercial Pt@Al2O3 catalyst (k = 0.09 × 10-3 min-1). Additionally, the Pt@cellulose catalyst can be used for electrochemical hydrogenation of para-nitrophenol where the hydrogen is electrocatalytically formed. The electrochemical hydrogenation is faster compared to the transfer hydrogenation (k = 0.11 min-1).

2.
Phys Rev Lett ; 127(12): 127202, 2021 Sep 17.
Article in English | MEDLINE | ID: mdl-34597094

ABSTRACT

In oxide heterostructures, different materials are integrated into a single artificial crystal, resulting in a breaking of inversion symmetry across the heterointerfaces. A notable example is the interface between polar and nonpolar materials, where valence discontinuities lead to otherwise inaccessible charge and spin states. This approach paved the way for the discovery of numerous unconventional properties absent in the bulk constituents. However, control of the geometric structure of the electronic wave functions in correlated oxides remains an open challenge. Here, we create heterostructures consisting of ultrathin SrRuO_{3}, an itinerant ferromagnet hosting momentum-space sources of Berry curvature, and LaAlO_{3}, a polar wide-band-gap insulator. Transmission electron microscopy reveals an atomically sharp LaO/RuO_{2}/SrO interface configuration, leading to excess charge being pinned near the LaAlO_{3}/SrRuO_{3} interface. We demonstrate through magneto-optical characterization, theoretical calculations and transport measurements that the real-space charge reconstruction drives a reorganization of the topological charges in the band structure, thereby modifying the momentum-space Berry curvature in SrRuO_{3}. Our results illustrate how the topological and magnetic features of oxides can be manipulated by engineering charge discontinuities at oxide interfaces.

4.
J Urol ; 180(2): 737-41, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18554637

ABSTRACT

PURPOSE: Interstitial cystitis is a chronic inflammatory disease of the bladder and luminal nitric oxide has been shown to be increased in the bladder in patients with interstitial cystitis. We analyzed endogenous nitric oxide formation and inducible nitric oxide synthase gene expression in the bladder of patients with interstitial cystitis to obtain further knowledge of the localization of inducible nitric oxide synthase in the bladder mucosa. MATERIALS AND METHODS: Six patients with interstitial cystitis and 8 controls were studied. In these 2 groups endogenous nitric oxide formation was measured and inducible nitric oxide synthase expression in bladder biopsies was analyzed at the transcriptional and protein levels by real-time polymerase chain reaction and Western blot, respectively. Immunohistochemistry for inducible nitric oxide synthase was also performed. RESULTS: Patients with interstitial cystitis had higher inducible nitric oxide synthase mRNA expression and nitric oxide formation than controls (p <0.01 and <0.001, respectively). Inducible nitric oxide synthase protein expression was up-regulated in the interstitial cystitis group. Immunohistochemistry showed that inducible nitric oxide synthase was predominantly localized to the urothelium in patients with interstitial cystitis but inducible nitric oxide synthase-like immunoreactivity was also found in macrophages in the bladder mucosa. CONCLUSIONS: The increased levels of endogenously formed nitric oxide in patients with interstitial cystitis correspond to increased inducible nitric oxide synthase mRNA expression and protein levels in these patients. Furthermore, inducible nitric oxide synthase was found to be localized to the urothelium but it was also found in macrophages in the bladder mucosa. Whether high levels of endogenously formed nitric oxide are a part of the pathogenesis in interstitial cystitis and whether it has a protective or damaging role remain to be elucidated.


Subject(s)
Biomarkers/metabolism , Cystitis, Interstitial/enzymology , Cystitis, Interstitial/pathology , Nitric Oxide Synthase Type II/metabolism , Aged , Biopsy, Needle , Blotting, Western , Cystitis, Interstitial/physiopathology , Disease Progression , Female , Gene Expression Regulation , Humans , Immunohistochemistry , Middle Aged , Nitric Oxide Synthase Type II/genetics , Prognosis , Reference Values , Reverse Transcriptase Polymerase Chain Reaction , Risk Assessment , Sensitivity and Specificity , Severity of Illness Index
5.
Article in English | MEDLINE | ID: mdl-19163514

ABSTRACT

In this contribution, a first prototype for mobile respiratory motion detection using optical fibers embedded into textiles is presented. The developed system consists of a T-shirt with an integrated fiber sensor and a portable monitoring unit with a wireless communication link enabling the data analysis and visualization on a PC. A great effort is done worldwide to develop mobile solutions for health monitoring of vital signs for patients needing continuous medical care. Wearable, comfortable and smart textiles incorporating sensors are good approaches to solve this problem. In most of the cases, electrical sensors are integrated, showing significant limits such as for the monitoring of anaesthetized patients during Magnetic Resonance Imaging (MRI). OFSETH (Optical Fibre Embedded into technical Textile for Healthcare) uses optical sensor technologies to extend the current capabilities of medical technical textiles.


Subject(s)
Fiber Optic Technology , Monitoring, Ambulatory/instrumentation , Monitoring, Physiologic/instrumentation , Monitoring, Physiologic/methods , Telemedicine/instrumentation , Algorithms , Clothing , Computers , Equipment Design , Humans , Monitoring, Ambulatory/methods , Motion , Respiration , Signal Processing, Computer-Assisted , Software , Telemedicine/methods , Telemetry , Textiles
6.
Theor Appl Genet ; 115(6): 793-805, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17646961

ABSTRACT

Sugar beet (Beta vulgaris) is an important root crop for sucrose production. A study was conducted to find a new abundant source of microsatellite (SSR) markers in order to develop marker assistance for breeding. Different sources of existing microsatellites were used and new ones were developed to compare their efficiency to reveal diversity in mapping population and mapping coverage. Forty-one microsatellite markers were isolated from a B. vulgaris ssp maritima genomic library and 201 SSRs were extracted from a B. vulgaris ssp vulgaris library. Data mining was applied on GenBank B. vulgaris expressed sequence tags (ESTs), 803 EST-SSRs were identified over 19,709 ESTs. Characteristics, polymorphism and cross-species transferability of these microsatellites were compared. Based on these markers, a high density genetic map was constructed using 92 F(2) individuals from a cross between a sugar and a table beet. The map contains 284 markers, spans over 555 cM and covers the nine chromosomes of the species with an average markers density of one marker every 2.2 cM. A set of markers for assignation to the nine chromosomes of sugar beet is provided.


Subject(s)
Beta vulgaris/genetics , Expressed Sequence Tags , Genome, Plant , Microsatellite Repeats , Breeding , Chromosome Mapping , Databases, Nucleic Acid , Genetic Linkage , Genetic Markers , Genomic Library , Polymorphism, Genetic , Repetitive Sequences, Nucleic Acid , Species Specificity
7.
Neurosci Lett ; 417(1): 36-41, 2007 Apr 24.
Article in English | MEDLINE | ID: mdl-17397999

ABSTRACT

In order to detect possible links between structural and neurochemical brain abnormalities we applied high resolution morphometric imaging and short-echo time absolute-quantification magnetic resonance spectroscopy (MRS) at the left hand side to the amygdala in 12 patients with borderline personality disorder (BPD) and 10 group-matched healthy controls. Confirming earlier reports we found a significant 11-17% reduction of amygdalar volumes in patients with BPD. In addition there was a significant 17% increase of left amygdalar creatine concentrations in BPD patients. Left amygdalar creatine concentration correlated positively with measures of anxiety and negatively with amygdalar volume. This pilot study of simultaneous amygdalar morphometry and spectroscopy in BPD reveals a possible link between amygdalar volume loss, psychopathology and neurochemical abnormalities in terms of creatine signals.


Subject(s)
Amygdala/metabolism , Amygdala/physiopathology , Borderline Personality Disorder/metabolism , Borderline Personality Disorder/physiopathology , Brain Chemistry/physiology , Energy Metabolism/physiology , Adult , Amygdala/pathology , Anxiety Disorders/diagnosis , Anxiety Disorders/metabolism , Anxiety Disorders/physiopathology , Atrophy/diagnosis , Atrophy/metabolism , Atrophy/physiopathology , Borderline Personality Disorder/diagnosis , Creatine/analysis , Creatine/metabolism , Female , Functional Laterality/physiology , Humans , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy , Male , Predictive Value of Tests , Up-Regulation/physiology
8.
Nucleic Acids Res ; 33(Database issue): D619-21, 2005 Jan 01.
Article in English | MEDLINE | ID: mdl-15608274

ABSTRACT

The crop expressed sequence tag database, CR-EST (http://pgrc.ipk-gatersleben.de/cr-est/), is a publicly available online resource providing access to sequence, classification, clustering and annotation data of crop EST projects. CR-EST currently holds more than 200,000 sequences derived from 41 cDNA libraries of four species: barley, wheat, pea and potato. The barley section comprises approximately one-third of all publicly available ESTs. CR-EST deploys an automatic EST preparation pipeline that includes the identification of chimeric clones in order to transparently display the data quality. Sequences are clustered in species-specific projects to currently generate a non-redundant set of approximately 22,600 consensus sequences and approximately 17,200 singletons, which form the basis of the provided set of unigenes. A web application allows the user to compute BLAST alignments of query sequences against the CR-EST database, query data from Gene Ontology and metabolic pathway annotations and query sequence similarities from stored BLAST results. CR-EST also features interactive JAVA-based tools, allowing the visualization of open reading frames and the explorative analysis of Gene Ontology mappings applied to ESTs.


Subject(s)
Crops, Agricultural/genetics , Databases, Nucleic Acid , Expressed Sequence Tags/chemistry , Genes, Plant , Database Management Systems , Hordeum/genetics , Pisum sativum/genetics , Sequence Analysis, DNA , Solanum tuberosum/genetics , Triticum/genetics , User-Computer Interface
9.
Inflamm Res ; 53 Suppl 2: S116-21, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15338061

ABSTRACT

OBJECTIVE: Antibiotic prophylaxis is used in many surgical procedures but there are frequent cardiovascular instabilities following antibiotics in perioperative period. A clinic modelling randomised trial (CMRT) in pigs was developed to compare the effects of 2 commonly used antibiotic combinations on cardiovascular stability during major surgery. MATERIALS AND METHODS: Thirty pigs (both sexes) were randomised into 3 groups, receiving either saline (placebo), co-amoxiclav or cefuroxime/metronidazole in clinically relevant doses as antibiotic prophylaxis. A laparotomy was performed and the abdomen remained open. Surgical complications were simulated by removing one third of the blood volume. For fluid resuscitation, 500 ml hetastarch (HAES(TM)) were infused rapidly (therapy of complication) and polymyxin B (15 mg/kg bodyweight) was applied for induction of histamine release reactions (complication of therapy). The main end points were histamine release reactions, these were classified by 2 blinded investigators. RESULTS: Neither cardiovascular changes nor histamine release reactions were detected immediately after the administration of antibiotics or placebo alone. Plasma histamine concentrations increased after bleeding in the co-amoxiclav group (p < 0.05). After fluid resuscitation and induction of anaphylactoid reactions, the median histamine release and cardiovascular changes were not significantly different between the groups. However, the incidence of typical histamine release related reactions differed significantly between the groups: 8/10 for the controls, 6/10 in the co-amoxiclav and 2/10 in the cefuroxime/metronidazole group (p < 0.05). CONCLUSIONS: The stability and reproducibility of this model clearly demonstrated the concept of a 'clinic modelling randomised trial' as a useful tool. Antibiotic prophylaxis influences the organism's capability to cope with intraoperative bleeding and fluid resuscitation problems. Indeed antibiotic prophylaxis may be beneficial. These effects of antibiotics could only be demonstrated in complex surgical models. Thus new antibiotics should be investigated in complex animal models prior to prospective randomised clinical trials or usage in clinical practice.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antibiotic Prophylaxis , Cardiovascular System/drug effects , Surgical Wound Infection/prevention & control , Animals , Blood Pressure/drug effects , Blood Pressure/physiology , Disease Models, Animal , Female , Heart Rate/drug effects , Heart Rate/physiology , Histamine Release/drug effects , Male , Random Allocation , Swine
10.
Magn Reson Med ; 52(4): 851-9, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15389967

ABSTRACT

The use of body coils is favored for homogeneous excitation, and such coils are often paired with surface coils or arrays for sensitive reception in many MRI applications. While the body coil's physical size and resultant electrical length make this circuit difficult to design for any field strength, recent efforts to build efficient body coils for applications at 3T and above have been especially challenging. To meet this challenge, we developed an efficient new transverse electromagnetic (TEM) body coil and demonstrated its use in human studies at field strengths up to 4 T. Head, body, and breast images were acquired within peak power constraints of <8 kW. Bench studies indicate that these body coils are feasible to 8 T. RF shimming was used to remove a high-field-related cardiac imaging artifact in these preliminary studies. P41RR13230


Subject(s)
Image Enhancement/instrumentation , Equipment Design , Humans , Magnetic Resonance Imaging/instrumentation
11.
Mol Genet Metab ; 82(3): 208-13, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15234333

ABSTRACT

Deficiency of guanidinoacetate methyltransferase (GAMT), the first described creatine biosynthesis defect, leads to depletion of creatine and phosphocreatine, and accumulation of guanidinoacetate in brain. This results in epilepsy, mental retardation, and extrapyramidal movement disorders. Investigation of skeletal muscle by proton and phosphorus magnetic resonance spectroscopy before therapy demonstrated the presence of considerable amounts of creatine and phosphocreatine, and accumulation of phosphorylated guanidinoacetate in a 7-year-old boy diagnosed with GAMT deficiency, suggesting separate mechanisms for creatine uptake and synthesis in brain and skeletal muscle. The combination of creatine supplementation and a guanidinoacetate-lowering therapeutic approach resulted in improvement of clinical symptoms and metabolite concentrations in brain, muscle, and body fluids.


Subject(s)
Brain/metabolism , Creatine/metabolism , Glycine/analogs & derivatives , Methyltransferases/deficiency , Muscle, Skeletal/metabolism , Arginine/blood , Child , Creatine/cerebrospinal fluid , Creatine/therapeutic use , Creatinine/blood , Creatinine/urine , Gas Chromatography-Mass Spectrometry , Glycine/blood , Glycine/cerebrospinal fluid , Glycine/urine , Guanidinoacetate N-Methyltransferase , Humans , Magnetic Resonance Spectroscopy , Male , Ornithine/blood , Phosphocreatine/metabolism , Turkey
12.
Neuroimage ; 20(1): 385-92, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14527598

ABSTRACT

Subtle prefrontal and limbic structural abnormalities have been reported in borderline personality disorder (BPD). In order to further validate the previously reported findings and to more precisely describe the nature of the structural change we performed a voxel-based morphometric (VBM) study in patients with BPD. Twenty female patients with BPD and 21 female healthy controls were investigated. High-resolution 3-D datasets were acquired and analyzed following an optimized protocol of VBM in the framework of statistical parametric mapping (SPM99). Gray matter volume loss was found in the left amygdala. No other differences in gray or white matter volume or density were found anywhere else in the brain. Our findings support the hypothesis that temporolimbic abnormalities play a role in the pathophysiology of BPD. Prefrontal structural alterations in BPD were not observed in this study.


Subject(s)
Borderline Personality Disorder/pathology , Brain/pathology , Magnetic Resonance Imaging , Adult , Amygdala/pathology , Borderline Personality Disorder/psychology , Cerebral Cortex/pathology , Female , Humans , Image Processing, Computer-Assisted , Limbic System/pathology , Probability , Psychiatric Status Rating Scales
13.
Mol Genet Genomics ; 270(1): 24-33, 2003 Oct.
Article in English | MEDLINE | ID: mdl-12938038

ABSTRACT

The public EST (expressed sequence tag) databases represent an enormous but heterogeneous repository of sequences, including many from a broad selection of plant species and a wide range of distinct varieties. The significant redundancy within large EST collections makes them an attractive resource for rapid pre-selection of candidate sequence polymorphisms. Here we present a strategy that allows rapid identification of candidate SNPs in barley (Hordeum vulgare L.) using publicly available EST databases. Analysis of 271,630 EST sequences from different cDNA libraries, representing 23 different barley varieties, resulted in the generation of 56,302 tentative consensus sequences. In all, 8171 of these unigene sequences are members of clusters with six or more ESTs. By applying a novel SNP detection algorithm (SNiPpER) to these sequences, we identified 3069 candidate inter-varietal SNPs. In order to verify these candidate SNPs, we selected a small subset of 63 present in 36 ESTs. Of the 63 SNPs selected, we were able to validate 54 (86%) using a direct sequencing approach. For further verification, 28 ESTs were mapped to distinct loci within the barley genome. The polymorphism information content (PIC) and nucleotide diversity (pi) values of the SNPs identified by the SNiPpER algorithm are significantly higher than those that were obtained by random sequencing. This demonstrates the efficiency of our strategy for SNP identification and the cost-efficient development of EST-based SNP-markers.


Subject(s)
Expressed Sequence Tags , Hordeum/genetics , Polymorphism, Single Nucleotide , Chromatography, High Pressure Liquid , DNA, Plant/genetics , DNA, Plant/isolation & purification , Genetic Markers , Molecular Sequence Data
14.
Theor Appl Genet ; 106(3): 411-22, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12589540

ABSTRACT

A software tool was developed for the identification of simple sequence repeats (SSRs) in a barley ( Hordeum vulgare L.) EST (expressed sequence tag) database comprising 24,595 sequences. In total, 1,856 SSR-containing sequences were identified. Trimeric SSR repeat motifs appeared to be the most abundant type. A subset of 311 primer pairs flanking SSR loci have been used for screening polymorphisms among six barley cultivars, being parents of three mapping populations. As a result, 76 EST-derived SSR-markers were integrated into a barley genetic consensus map. A correlation between polymorphism and the number of repeats was observed for SSRs built of dimeric up to tetrameric units. 3'-ESTs yielded a higher portion of polymorphic SSRs (64%) than 5'-ESTs did. The estimated PIC (polymorphic information content) value was 0.45 +/- 0.03. Approximately 80% of the SSR-markers amplified DNA fragments in Hordeum bulbosum, followed by rye, wheat (both about 60%) and rice (40%). A subset of 38 EST-derived SSR-markers comprising 114 alleles were used to investigate genetic diversity among 54 barley cultivars. In accordance with a previous, RFLP-based, study, spring and winter cultivars, as well as two- and six-rowed barleys, formed separate clades upon PCoA analysis. The results show that: (1) with the software tool developed, EST databases can be efficiently exploited for the development of cDNA-SSRs, (2) EST-derived SSRs are significantly less polymorphic than those derived from genomic regions, (3) a considerable portion of the developed SSRs can be transferred to related species, and (4) compared to RFLP-markers, cDNA-SSRs yield similar patterns of genetic diversity.


Subject(s)
DNA, Plant/genetics , Expressed Sequence Tags , Genes, Plant , Hordeum/genetics , Microsatellite Repeats , Polymorphism, Single Nucleotide , Databases, Factual , Genetic Linkage , Genetic Markers , Genome, Plant , Repetitive Sequences, Nucleic Acid , Time Factors
15.
Neurosci Lett ; 328(3): 319-21, 2002 Aug 16.
Article in English | MEDLINE | ID: mdl-12147334

ABSTRACT

Attention deficit hyperactivity disorder (ADHD) is a common psychiatric disorder in childhood and adolescence and in a considerable number of patients it persists into adulthood. A network of brain regions have been shown to be abnormal in ADHD. In the present study we used magnetic resonance volumetry to investigate a possible role of the orbitofrontal cortex (OFC). Eight never medicated male patients fulfilling diagnostic criteria for ADHD and 17 male healthy controls were investigated. There was a significant reduction of the volume of the left OFC in patients with ADHD. It remains unknown whether small volumes are a primary deficit or a result of dysfunctional activation during childhood in terms of a residual deficit or a specific type of adult outcome of the disease.


Subject(s)
Attention Deficit Disorder with Hyperactivity/diagnosis , Frontal Lobe/pathology , Magnetic Resonance Imaging , Adult , Humans , Male
16.
Eur Radiol ; 12(4): 858-61, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11960238

ABSTRACT

Nonketotic hyperglycinemia (NKH) is an inborn error of amino acid metabolism caused by a defect in the glycine cleavage multienzyme complex resulting in high concentrations of glycine within the brain and spinal cord. Quantitative magnetic resonance spectroscopy ((1)H-MRS) allows measurement of absolute glycine concentrations within different parts of the brain in vivo. In addition, (1)H-MRS may be useful in monitoring treatment of NKH and to differentiate this disease from other disorders of glycine metabolism.


Subject(s)
Brain/metabolism , Hyperglycinemia, Nonketotic/diagnosis , Brain Chemistry , Glycine/analysis , Humans , Infant, Newborn , Magnetic Resonance Spectroscopy , Male
17.
J Neuropsychiatry Clin Neurosci ; 13(4): 511-4, 2001.
Article in English | MEDLINE | ID: mdl-11748321

ABSTRACT

The authors examined the brains of patients with borderline personality disorder (BPD) by using short echo time single voxel spectroscopy and found a significant 19% reduction of absolute N-acetylaspartate concentrations in the dorsolateral prefrontal cortex in BPD (P=0.01) compared with control subjects.


Subject(s)
Aspartic Acid/analogs & derivatives , Aspartic Acid/metabolism , Borderline Personality Disorder/diagnosis , Energy Metabolism/physiology , Magnetic Resonance Spectroscopy , Prefrontal Cortex/pathology , Adult , Blood Glucose/metabolism , Borderline Personality Disorder/pathology , Brain Mapping , Corpus Striatum/pathology , Female , Humans , Reference Values
18.
Neurosci Lett ; 304(1-2): 117-9, 2001 May 18.
Article in English | MEDLINE | ID: mdl-11335068

ABSTRACT

The DSM-IV distinguishes three subtypes of attention deficit hyperactivity disorder: The predominantly inattentive subtype (ADD), the hyperactive-impulsive subtype (ADHD) and the combined subtype. We used short echo time (1)H-magnetic resonance spectroscopy (TE=30 ms, TR=3000 ms) for absolute quantification of neurometabolites using the LC model algorithm to investigate a possible metabolic neuropathology in adult patients with ADD and ADHD and compared their spectra with healthy controls (n=5 in each group). Spectra were acquired in the left dorsolateral prefrontal cortex and the left striatum. There was a significant group difference in N-acetylaspartate (NAA) concentration in the left dorsolateral prefrontal cortex distinguishing patients with the ADHD from patients with pure ADD and healthy controls. The absolute NAA concentration was significantly reduced only in the ADHD group. Since NAA-depletion reflects a state of neuronal dysfunction, this finding indicates evidence of subtle left prefrontal neuropathology in ADHD in adults.


Subject(s)
Aspartic Acid/metabolism , Attention Deficit Disorder with Hyperactivity/metabolism , Corpus Striatum/metabolism , Magnetic Resonance Spectroscopy/methods , Prefrontal Cortex/metabolism , Adult , Analysis of Variance , Attention Deficit Disorder with Hyperactivity/diagnosis , Corpus Striatum/pathology , Humans , Male , Prefrontal Cortex/pathology
19.
AJNR Am J Neuroradiol ; 22(5): 824-30, 2001 May.
Article in English | MEDLINE | ID: mdl-11337322

ABSTRACT

SUMMARY: Lhermitte-Duclos disease (LDD) is a rare cerebellar lesion with features of both malformation and benign neoplasm. However, the fundamental nature of the entity, its pathogenesis, and the exact genetic alterations remain unknown. We describe MR findings (including perfusion- and diffusion-weighted images) in two patients with LDD, as well as findings from single-photon emission CT (SPECT), MR spectroscopy (MRS), and fluorodeoxyglucose (FDG) positron emission tomography (PET) that give additional information about tumor pathophysiology. MR imaging usually distinguishes the LDD by its characteristic "tiger-striped" appearance. The regions of increased regional cerebral blood volume (rCBV) within the lesion correlated closely to the regions of FDG-hypermetabolism and high thallium (201-Tl) uptake. Proton MRS revealed an increased level of lactate and decreased level of myo-inositiol and N-acetyl-aspartate, as observed in low-grade gliomas, but decreased levels of choline. Our cases indicate that the functional investigations give additional information about tumor pathophysiology and reflect the histopathologic controversial entity with both characteristics found in low-grade gliomas and characteristics not typical for tumors.


Subject(s)
Cerebellar Neoplasms/diagnosis , Ganglioneuroma/diagnosis , Adult , Cerebellar Neoplasms/pathology , Female , Ganglioneuroma/pathology , Humans , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy , Male , Middle Aged , Tomography, Emission-Computed , Tomography, Emission-Computed, Single-Photon , Tomography, X-Ray Computed
20.
Ann Neurol ; 49(4): 518-21, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11310630

ABSTRACT

N-acetylaspartate (NAA) contributes to the most prominent signal in proton magnetic resonance spectroscopy (1H-MRS) of the adult human brain. We report the absence of NAA in the brain of a 3-year-old child with neurodevelopmental retardation and moderately delayed myelination. Since normal concentration of NAA in body fluids is hardly detectable, 1H-MRS is a noninvasive technique for identifying neurometabolic diseases with absent NAA. This report puts NAA as a neuronal marker to question.


Subject(s)
Aspartic Acid/analogs & derivatives , Aspartic Acid/analysis , Brain/metabolism , Magnetic Resonance Spectroscopy , Nervous System Diseases/metabolism , Child, Preschool , Dipeptides/analysis , Humans , Male
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