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A Petzold

Publications and source records attributed to A Petzold.

At least 37 records · Page 2Linked to original sources
PubMed2004

An ELISA for glial fibrillary acidic protein.

Glial fibrillary acidic protein (GFAP) is the major intermediate filament protein of the astrocyte, and body fluid levels of GFAP are an important tool for estimating astrogliosis and astrocytic activation in vivo. This paper presents a new sandwich ELISA allowing quantification of GFAP(SMI26) from the cerebrospinal fluid (CSF). The sensitivity of the GFAP(SMI26) ELISA is 5 pg/ml with a recovery of 94% and a mean within- and between-batch precision of 6% and 10%, respectively. The upper reference value for CSF GFAP(SMI26) levels (9 pg/ml) was defined as the 95% cumulative frequency from 315 CSF samples. Based on this cut-off, a significantly higher proportion of patients with subarachnoid hemorrhage (100%), traumatic brain injury (100%), dementia (76%) and normal pressure hydrocephalus (85%) had pathologically elevated CSF GFAP(SMI26) levels compared to patients with peripheral nervous system disorders (0%). In a critical review of the literature, we compare the analytical and clinical sensitivity of previous GFAP ELISA methods with particular reference to patients with dementia.

Animals↗
PubMed2004

Axonal degeneration and inflammation in acute optic neuritis.

AIMS: To investigate whether plasma biomarkers for axonal injury and inflammation are related to loss and recovery of visual function in acute optic neuritis (ON). METHODS: Eighteen patients with ON and 14 controls were investigated in a longitudinal, prospective study. Plasma phosphorylated neurofilament heavy chain (NfHSMI35; a surrogate marker of axonal injury), nitric oxide metabolites (NOx), and citrulline (surrogate markers of inflammation) were measured. RESULTS: Patients with ON had higher median plasma NfHSMI35 values than controls (0.17 versus 0.005 ng/ml; p < 0.05) and higher NOx values (49 versus 35.5 microM; p < 0.001). Plasma NfHSMI35 values correlated inversely with visual acuity at presentation (R = -0.67; p = 0.01). NfHSMI35 was higher in patients with poor recovery of visual acuity than in those with good recovery (0.25 ng/ml versus 0.09 ng/ml; p < 0.05). Three of four patients with high NfHSMI35 and high NOx values experienced a poor recovery as opposed to only one of five with high NOx but normal NfH(SMI35) values. CONCLUSIONS: NfHSMI35, a surrogate marker for axonal damage, is a prognostic indicator and should be considered in the design of neuroprotective treatment strategies.

Acute Disease↗
PubMed2004

Treatment response in relation to inflammatory and axonal surrogate marker in multiple sclerosis.

BACKGROUND: This study aimed to investigate if treatment response could retrospectively be related to inflammatory or axonal pathology as measured by plasma surrogate markers. METHODS: In this 1-year observational study 30 multiple sclerosis (MS) patients with relapsing-remitting disease were treated with intramuscular IFNbeta-1a or subcutaneous IFNbeta-1b. Responders and nonresponders were defined according to clinical and magnetic resonance imaging criteria. The control group consisted of 14 healthy subjects. Plasma levels of surrogate markers for inflammation (nitric oxide metabolites (NOx)), astrocytic activation (S100B) and axonal damage (NfH(SM135)) were measured using standard assays. RESULTS: There were 11 nonresponders and 19 responders to IFNbeta treatment. Median S100B levels were elevated in a higher proportion of treatment responders (63%, 42.9 pg/mL) compared to nonresponders (18%, 11.7 pg/mL, P < 0.05, Fisher's exact test) and controls (0%, 2 pg/mL, P < 0.001). Levels of NOx were found to be more frequently elevated in nonresponders (72%, 39 microM) compared to healthy controls (0%, 37 microM, P < 0.05). Levels of NfH(SM135) were more frequently elevated in responders (58%, 300 pg/mL, P < 0.001) and nonresponders (72%, 500 pg/mL, P < 0.001) compared to controls (0%, 4.5 pg/mL). CONCLUSION: Patients with relapsing-remitting MS who had surrogate marker supported evidence for astrocytic activation responded more frequently to treatment with IFNbeta.

Adjuvants, Immunologic↗
PubMed2003

Cerebrospinal fluid (CSF) and serum S100B: release and wash-out pattern.

S100B is an important brain specific protein for monitoring damage and activation of astrocytes. Using a straight forward, non-resource demanding in-house ELISA technique we measured S100B in cerebrospinal fluid (CSF) and serum in patients with traumatic brain injury (TBI) (serum), subarachnoid hemorrhage (SAH) (CSF, serum), intracranial hemorrhage (ICH) (CSF, serum), normal controls (NC) (serum) and a reference population (CSF, N=409). The release and wash-out pattern found in CSF and serum are discussed in relation to the three main determinants for increased brain specific protein levels in body fluids: (i) total mass effect; (ii) pathology; and (iii) time effect.

Adult↗
PubMed2003

Serum and urine nitrate and nitrite are not reliable indicators of intrathecal nitric oxide production in acute brain injury.

This study examined the correlation between nitric oxide (NO) metabolites in the three major body fluid compartments and assessed performance of newly described vanadium-based assay for simultaneous detection of nitrite and nitrate (NO(x)) in human samples. Vanadium reduces nitrate to nitrite, which can be measured after a colorimetric reaction with Griess reagents. Cisternal cerebro spinal fluid (CSF), serum and urine samples from 10 patients with acute brain injury (ABI) were compared to control subjects. Significantly higher CSF NO(x) levels were found in brain injury patients compared to control patients (19.7+/-13.7 vs. 6.5+/-2.3 microM; p=0.01), which persisted for 10-day period of observation. The serum and urine levels of NO(x) on admission were not statistically different (42.8+/-28.2 microM; 584.1+/-337.8 micromol/g Cr, respectively) from controls (36.8+/-14.8 microM; 819.7+/-356.0 micromol/g Cr), but tended to decrease during the disease course reaching the lowest level on day 6 (serum: 19.3+/-8.4 microM, urine: 300.4+/-111.9 micromol/g Cr). CSF levels of NO(x) correlated moderately with those in serum (p=0.001, R=0.5). Serum NO(x) concentrations correlated weakly with urine levels (p=0.04, R=0.3). There was no significant correlation between CSF NO(x) and urine NO(x) levels. In conclusion, patients suffering brain injury had increased NO(x) concentrations in CSF, which remained independent from other body fluid compartments. Serum and urinary NO(x) levels cannot be used as a reliable index to assess intrathecal NO production.

Adult↗
PubMed2003

Multiple sclerosis: Neurofilament light chain antibodies are correlated to cerebral atrophy.

OBJECTIVE: To evaluate markers of axonal damage in CSF and serum of patients with different subtypes of MS in relation to measures of disease progression on MRI. METHODS: In 51 patients with MS (21 relapsing-remitting, 20 secondary progressive, 10 primary progressive), levels of heavy and light neurofilaments (NfH and NfL) and antibodies to neurofilaments (anti-NfL and -NfH) as well as the total immunoglobulin G (IgG) were analyzed. MRI analysis included T2 hyperintense, T1 hypointense, and gadolinium enhancing lesions and markers of cerebral atrophy (ventricular and parenchymal fractions). RESULTS: For the total group, correlations were found between the anti-NfL index and the parenchymal fraction (PF) (r = -0.51, p < 0.001), T2 lesion load (r = 0.41, p < 0.05), ventricular fraction (r = 0.37, p < 0.05), and T1 lesion load (r = 0.37, p < 0.05). For the anti-NfH index, a correlation was found with the PF (r = -0.39, p < 0.05). No correlations were found between the IgG index and MRI measures. CONCLUSIONS: Intrathecal production of anti-NfL antibodies may serve as a marker of tissue damage, particularly axonal loss, in MS.

Adult↗
PubMed2003

Cerebrospinal fluid S100B correlates with brain atrophy in Alzheimer's disease.

S100B is a predominantly astrocytic protein with dose-dependent cytotoxic and neurotrophic properties encoded on chromosome 21q22.3. Concentrations of S100B were measured in the cerebrospinal fluid (CSF) of 31 patients with Alzheimer's disease (AD), 36 patients with frontotemporal lobe dementia (FTLD) and 49 patients with other non-inflammatory neurological diseases. Additional CSF S100B concentrations were correlated with normalised brain volume measurements in AD and FTLD. CSF S100B was significantly higher in AD (Mean+/-standard deviation=0.4+/-0.2 ng/ml) and FTLD (0.42+/-0.19 ng/ml) patients when compared with control subjects (0.25+/-0.08, P<0.001). In patients with AD, S100B correlated negatively with normalised brain volume (R(S)=-0.53, P<0.001). No such correlation was found for FTLD patients. This study supports the concept that S100B is of pathological relevance for degeneration of the central nervous system in AD.

Adult↗
PubMed2003

A specific ELISA for measuring neurofilament heavy chain phosphoforms.

Neurofilaments (Nf) are the major constitutents of the axoskeleton and body fluid Nf levels are an important tool for estimating axonal degeneration in vivo. This paper presents a new sandwich ELISA allowing quantification of the NfH(SMI35) phosphoform from CSF, brain tissue and cell culture homogenates. The sensitivity of the NfH(SMI35) ELISA is 0.2 ng/ml with a recovery of 119% and a mean within- and between-batch precision of 10.6% and 23%, respectively. CSF NfH(SMI35) was stable at 4 degrees C, is not influenced by freeze-thaw cycles, and proteolysis present at room temperature could be prevented by adding protease inhibitors. Aggregate formation was observed for HPLC-purified bovine NfH and could be resolved by sonication. The upper reference value for CSF NfH(SMI35) levels (0.73 ng/ml) was defined as the 95% cumulative frequency from 416 CSF samples. Based on this cutoff, a significantly higher proportion of patients with amyotrophic lateral sclerosis, space-occupying lesions, disc prolapse and subarachnoid haemorrhage had pathologically elevated NfH(SMI35) levels compared to patients with cluster headache or demyelinating disease.A new nomenclature is proposed to facilitate the comparison between ELISA, immunoblotting and immunocytochemistry.

Animals↗
PubMed2003

Quantification of neurodegeneration by measurement of brain-specific proteins.

Quantification of neurodegeneration in animal models is typically assessed by time-consuming and observer-dependent immunocytochemistry. This study aimed to investigate if newly developed ELISA techniques could provide an observer-independent, cost-effective and time-saving tool for this purpose. Neurofilament heavy chain (NfH(SM135)), astrocytic glial fibrillary acidic protein (GFAP), S100B and ferritin, markers of axonal loss, gliosis, astrocyte activation and microglial activation, respectively, were quantified in the spinal cord homogenates of mice with chronic relapsing experimental allergic encephalomyelitis (CREAE, n=8) and controls (n=7). Levels of GFAP were found to be threefold elevated in CREAE (13 ng/mg protein) when compared to control animals (4.5 ng/mg protein, p<0.001). The inverse was observed for NfH(SM135) (21 ng/mg protein vs. 63 ng/mg protein, p<0.001), ferritin (542 ng/mg protein vs. 858 ng/mg protein, p<0.001) and S100B (786 ng/mg protein vs. 2080 ng/mg protein, N.S.). These findings were confirmed by immunocytochemistry, which demonstrated intense staining for GFAP and decreased staining for NfH(SM135) in CREAE compared to control animals. These findings indicate that axonal loss and gliosis can be estimated biochemically using the newly developed ELISA assays for NfH(SM135) and GFAP. These assays may facilitate the quantification of pathological features involved in neurodegeneration.

Animals↗
PubMed2003

Molecular monitoring of response to imatinib (Glivec) in CML patients pretreated with interferon alpha. Low levels of residual disease are associated with continuous remission.

A significant proportion of chronic myeloid leukemia (CML) patients achieve a major cytogenetic remission (MCR) to imatinib therapy after failing interferon (IFN) alpha-based protocols. We sought to determine levels of residual disease in patients with MCR using various molecular methods and to establish a relation between residual BCR-ABL transcript levels and rate of relapse in complete cytogenetic remission (CCR). Response was measured by conventional cytogenetic analysis, hypermetaphase and interphase fluorescence in situ hybridization (HM-FISH, IP-FISH) of bone marrow (BM) cells, qualitative nested and quantitative reverse transcriptase polymerase chain reaction (RT-PCR) for BCR-ABL transcripts. We investigated 323 peripheral blood (PB) and BM samples from 48 CML patients who achieved a complete (Ph+ 0%; n=41) or partial (Ph+ 1-34%; n=7) cytogenetic remission after 3-20 months of imatinib therapy. Prior to imatinib, 35 patients were in chronic phase (CP), eight in accelerated phase (AP), four in myeloid and one in lymphoid blast crisis. HM-FISH results correlated with ratios BCR-ABL/ABL in PB and BM. In patients with CCR, residual disease was detectable by HM-FISH (31%), IP-FISH (18%), and RT-PCR (100%). During follow-up, BCR-ABL became undetectable in two patients (one CP, one AP) by both nested and quantitative RT-PCR. CCR is ongoing in 30 evaluable patients, 11 patients have relapsed. At the time of best response, median ratios BCR-ABL/ABL were 2.1% (range 0.82-7.8) in patients with subsequent relapse and 0.075% (range 0-3.9) in patients with ongoing remission (P=0.0011). All 16 CP patients, who achieved ratios BCR-ABL/ABL <0.1% as best molecular response are in continuous remission, while 6/13 patients (46%) with ratios >/=0.1% have relapsed (P=0.0036). We conclude that: (i) in patients with CCR to imatinib, HM-FISH and RT-PCR usually reveal residual BCR-ABL+ cells; (ii) RT-PCR results derived from PB and BM are comparable in CP CML; and (iii) low levels of residual disease with ratios BCR-ABL/ABL &<0.1% are associated with continuous remission.

Adult↗
PubMed2002

Markers for different glial cell responses in multiple sclerosis: clinical and pathological correlations.

Disease progression in multiple sclerosis occurs within the interface of glial activation and gliosis. This study aimed to investigate the relationship between biomarkers of different glial cell responses: (i) to disease dynamics and the clinical subtypes of multiple sclerosis; (ii) to disability; and (iii) to cross-validate these findings in a post-mortem study. To address the first goal, 51 patients with multiple sclerosis [20 relapsing remitting (RR), 21 secondary progressive (SP) and 10 primary progressive (PP)] and 51 neurological control patients were included. Disability was assessed using the ambulation index (AI), the Expanded Disability Status Scale score (EDSS) and the 9-hole PEG test (9HPT). Patients underwent lumbar puncture within 7 days of clinical assessment. Post-mortem brain tissue (12 multiple sclerosis and eight control patients) was classified histologically and adjacent sites were homogenized for protein analysis. S100B, ferritin and glial-fibrillary acidic protein (GFAP) were quantified in CSF and brain-tissue homogenate by ELISA (enzyme-linked immunosorbent assay) techniques developed in-house. There was a significant trend for increasing S100B levels from PP to SP to RR multiple sclerosis (P < 0.05). S100B was significantly higher in RR multiple sclerosis than in control patients (P < 0.01), whilst ferritin levels were significantly higher in SP multiple sclerosis than in control patients (P < 0.01). The S100B : ferritin ratio discriminated patients with RR multiple sclerosis from SP, PP or control patients (P < 0.05, P < 0.01 and P < 0.01, respectively). Multiple sclerosis patients with poor ambulation (AI > or =7) or severe disability (EDSS >6.5) had significantly higher CSF GFAP levels than less disabled multiple sclerosis or control patients (P < 0.01 and P < 0.001, respectively). There was a correlation between GFAP levels and ambulation in SP multiple sclerosis (r = 0.57, P < 0.01), and between S100B level and the 9HPT in PP multiple sclerosis patients (r = -0.85, P < 0.01). The post-mortem study showed significantly higher S100B levels in the acute than in the subacute plaques (P < 0.01), whilst ferritin levels were elevated in all multiple sclerosis lesion stages. Both GFAP and S100B levels were significantly higher in the cortex of multiple sclerosis than in control brain homogenate (P < 0.001 and P < 0.05, respectively). We found that S100B is a good marker for the relapsing phase of the disease (confirmed by post-mortem observation) as opposed to ferritin, which is elevated throughout the entire course. GFAP correlated with disability scales and may therefore be a marker for irreversible damage. The results of this study have broad implications for finding new and sensitive outcome measures for treatment trials that aim to delay the development of disability. They may also be considered in future classifications of multiple sclerosis patients.

Adult↗
PubMed2001

Recurrent ptosis.

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Blepharoptosis↗
PubMed2001

Relapsing intracranial Rosai-Dorfman disease.

Two patients presenting with recurrent visual impairment due to relapsing intracranial Rosai-Dorfman disease are described. In both patients a preoperative diagnosis of meningioma was made. Histological examination disclosed the characteristic picture of S100 and CD68 positive histiocytosis with prominent lymphophagocytosis. In both patients complete tumour removal by surgery was impossible with residual tissue being the origin of relapsing disease. Low dose radiation led to partial recovery of vision and resolution of the intracranial mass. Review of the literature on intracranial Rosai-Dorfman disease leads to the suggestion that postoperative radiotherapy may be advisable in all cases.

Aged↗