Biomedical subjects

Ellen Gelpi

Publications and source records attributed to Ellen Gelpi.

28 records · Page 2Linked to original sources

PubMed2005

Visualization of Central European tick-borne encephalitis infection in fatal human cases.

Central European tick-borne encephalitis (TBE) is caused by a flavivirus vectored by the Ixodes ricinus tick. In severe infections, TBE presents as (myelo)meningoencephalitis with considerable mortality. Characteristic neuropathologic changes feature a multinodular to patchy polioencephalomyelitis accentuated in spinal cord, brainstem, and cerebellum. Visualization of viral infection by immunohistochemistry has not yet been achieved. We analyzed immunohistochemically the distribution of viral antigens and its correlation with neuropathologic changes, serological data, and disease duration in 28 brains of cases with a clinical diagnosis of TBE and neuropathologically confirmed (meningo)encephalomyelitis. In 20 brains (including 10 seropositives), viral antigens were detectable. These cases were characterized by relatively short clinical duration ranging from 4 to 35 days. Immunoreactivity was most prominent in perikarya and processes of Purkinje cells and large neurons of dentate nucleus, inferior olives, and anterior horns. In addition, immunoreactivity was detected in neurons of other brainstem nuclei, isocortex, and basal ganglia. There was an inverse topographical association of severe inflammatory changes with presence of viral antigens. Some cytotoxic T cells were in direct contact with tick-borne encephalitis virus (TBEV)-infected neurons. We conclude that 1) TBE viral antigens are immunohistochemically detectable in brains of fatal cases with relatively short natural clinical course; 2) TBE virus neurotropism preferentially targets large neurons of anterior horns, medulla oblongata, pons, dentate nucleus, Purkinje cells, and striatum; 3) topographical correlation between inflammatory changes and distribution of viral antigens is poor; and 4) immunologic mechanisms may contribute to nerve cell destruction in human TBE.

Adolescent↗

PubMed2005

Recurrent and metastatic clivus chordoma: systemic palliative therapy retards disease progression.

We report on a male patient with progressive and metastatic clivus chordoma treated over a period of 9 years by a multidisciplinary approach. Within the first 4 years, the patient underwent surgery four times. Thereafter, he received radiotherapy and subsequent chemotherapy. Stabilization of disease was achieved repeatedly for variable periods under local radiotherapy, systemic chemotherapy, immunomodulatory and anti-angiogenic therapy with isotretinoin and interferon-alpha, followed by thalidomide. Due to the occurrence of brain and lung metastases 8 years after initial diagnosis, liposomal doxorubicin was added to thalidomide. At the last follow-up control the patient had stable disease, with no progression of the intracranial tumor and regression of pulmonary metastases. He is in a good physical, psychological and neurological condition with a Karnofsky score of 80. Our observations show that multimodal therapy including a systemic palliative approach is associated with long quiescent intervals in recurrent chordoma and with regression of its metastases. Use of substances with high efficacy on tumor tissue and low toxicity, allowing long-term administration, seems promising in similar situations.

Chordoma↗

PubMed2005

Pleomorphic xanthoastrocytoma with anaplastic features presenting without GFAP immunoreactivity: implications for differential diagnosis.

Pleomorphic xanthoastrocytoma (PXA) is an uncommon, usually low-grade, astrocytic tumor. Characteristic histological features include tumor cell pleomorphism and lipidization of tumor cells. Albeit prognosis in PXA is generally good, cases with histological signs of anaplasia have been observed. In these cases, the differential diagnosis needs to exclude other malignancies, for example, glioblastoma or malignant fibrous histiocytoma. Immunocytochemical detection of GFAP may support exclusion of non-glial neoplasms resembling PXA. However, GFAP expression in PXA may be faint or focal, although complete lack of GFAP has not been described. A 43-year-old woman was operated on for a left occipital parasagital tumor attached to the dura. Histopathology showed a pleomorphic tumor with moderate mitotic activity and necrosis, lack of GFAP immunoreactivity and ultrastructural detection of premelanosome-like structures. These features led to the tentative diagnosis of amelanotic melanoma, and the patient was irradiated. Three years later she had local tumor recurrence and underwent another operation. The recurrent tumor showed similar plain histology as the first specimen. In contrast, anti-GFAP immunoreactivity was now detectable in pleomorphic tumor cells. Anti-GFAP staining of the first biopsy was repeated using monoclonal and polyclonal antibodies in combination with prolonged tissue pretreatment. Focal GFAP staining of tumor cells was now achieved. We conclude that non-standard GFAP staining protocols may enhance sensitivity and thus lead to detection of a low level of GFAP expression in tumor specimens, in which PXA is considered in the differential diagnosis. This may avoid misleading diagnostic considerations that impact on postoperative patient management.

Adult↗

PubMed2005

Left ventricular hypertrabeculation/noncompaction as a cardiac manifestation of Duchenne muscular dystrophy under non-invasive positive-pressure ventilation.

Though cardiac involvement is a frequent finding in patients with Duchenne muscular dystrophy (DMD) at the wheel-chair-bound stage, left ventricular hypertrabeculation (LVHT) has not been reported. The patient is a 28-year-old male with the typical clinical features of end stage DMD. Since the age of 16 years he required ventilatory support by means of non-invasive positive-pressure ventilation (NIPPV), initially intermittently and since age 27 permanently. Since the age of 21 years he developed chronic heart failure, and since age 24 atrial flutter, successfully treated with amiodarone. After discontinuation of amiodarone because of hyperthyroidism, he developed atrial fibrillation. Echocardiography at age 28 revealed mitral insufficiency, enlarged left atrial diameter, and, surprisingly, LVHT. Since LVHT was absent at the initial echocardiographic examination, it was regarded acquired. The case shows that cardiac involvement in DMD may not only comprise rhythm abnormalities, valve abnormalities, and dilative cardiomyopathy, but also LVHT in single cases.

Adult↗

PubMed2004

Expression of hypoxia-related tissue factors correlates with diminished survival of adjuvantly treated patients with chromosome 1p aberrant oligodendroglial neoplasms and therapeutic implications.

PURPOSE: Oligodendroglial neoplasms with chromosome 1p deletion are chemosensitive, and stratified adjuvant therapies have been proposed on the basis of 1p status. In this study, we evaluated expression of hypoxia-related factors and its influence on survival in oligodendroglial brain tumors with chromosome 1p aberrations. EXPERIMENTAL DESIGN: Forty-four primary and 16 recurrent oligodendroglial neoplasms with 1p aberrations (deletion or imbalance) were investigated immunohistochemically for expression of hypoxia-inducible factor 1alpha and carbonic anhydrase-9. We used in situ hybridization to investigate expression of vascular endothelial growth factor-mRNA. We defined as "low hypoxia score" expression of no or only one marker and as "high hypoxia score" expression of two or three markers. The predominant vascular patterns of tumors were defined as classic or bizarre vascular formations, based on anti-CD34-immunostaining. RESULTS: High hypoxia score was evident in 16 of 44 (36.4%) primary tumor specimens and in 14 of 16 (87.5%) recurrent tumors (P = 0.001). High hypoxia score was associated with the presence of bizarre vascular proliferations and WHO grade III. In the subgroup of patients who received adjuvant therapy, univariate analysis showed significantly shorter survival of patients with high hypoxia score (n = 27; P = 0.0145). For all of the primary tumors, hypoxia score was an independent prognostic factor (P = 0.045). CONCLUSIONS: A fraction of oligodendroglial neoplasms with 1p aberrations shows evidence of tissue hypoxia, which significantly influences survival of patients receiving adjuvant therapy. Evaluation of tissue hypoxia could become useful for recruitment of patients for individualized therapy strategies, e.g., selection of patients with hypoxic tumors for hyperbaric oxygenation preceding radiotherapy.

Adult↗

PubMed2004

Value and limits of immunohistochemistry in differential diagnosis of clear cell primary brain tumors.

Clear cell histology is the hallmark of oligodendroglioma (OG) but also characterizes clear cell ependymoma (CCE) and central neurocytoma (CN). Immunohistochemistry for glial and neuronal proteins may support differential diagnosis. We investigated systematically diagnostic value and limits of immunohistochemistry using representative tumor specimens (>1 cm in diameter) of well-defined OGs, CCEs, and CNs (n=10, respectively). Antibodies comprised anti-neuron specific nuclear protein (NEUN), anti-synaptophysin, anti-neuron-specific enolase, anti-microtubule-associated protein 2, anti-phosphorylated neurofilament protein, anti-non-phosphorylated neurofilament protein, anti-glial fibrillary acidic protein (GFAP), anti-S100 protein, anti-vimentin (VIM), and anti-epithelial membrane antigen (EMA). Among the panel of antibodies anti-NEUN, anti-VIM and anti-EMA proved most useful for differential diagnosis. Prominent (>90%) anti-NEUN immunolabeling of tumor cells clearly distinguished CNs from OGs and CCEs. Anti-VIM immunolabeling and a characteristic cytoplasmic dot-like anti-EMA immunoreactivity pattern of tumor cells were detectable only in OGs and CCEs. Furthermore, prominent anti-VIM immunoreactivity and anti-EMA cell membrane staining including ring-like staining pattern is characteristic for CCEs. Additionally, a widespread gliofibrillary and minigemistocytic cytoplasmic anti-GFAP immunostaining pattern is restricted to some OGs. Our data indicate that immunohistochemistry using anti-NEUN, anti-VIM, and anti-EMA on representative tumor specimens allows clear-cut distinction of CNs vs OGs and CCEs. Anti-VIM, anti-EMA, and anti-GFAP support differential diagnosis of OGs vs CCEs. Nevertheless, it is noted that due to focal expression of glial proteins in CNs and, conversely, of neuronal proteins in OGs and CCEs, immunohistochemistry is of limited value on small tumor specimens.

Biomarkers, Tumor↗

PubMed2004

The prion protein in human neuromuscular diseases.

The basis of human prion diseases affecting the nervous system is accumulation of a disease-associated conformer (PrPSc) of the normal cellular prion protein (PrPC). Earlier studies demonstrated increased expression of PrPC in inclusion body myositis (IBM), dermato-, and polymyositis, as well as neurogenic muscle atrophy. To define the spectrum and reliability of PrPC immunoreactivity, its expression was examined systematically in a series of pathologically characterized muscular disorders by means of immunohistochemistry, confocal laser microscopy, and immunogold electron microscopy. Anti-PrPC immunolabelling of rimmed vacuoles was observed in IBM, inclusions of myofibrillary myopathy, targets, regenerating, and atrophic fibres, mononuclear cells, in addition to ragged red fibres in mitochondrial myopathies, and focal sarcolemmal immunostaining in non-diseased controls. Quantitative analysis demonstrated that, in neurogenic muscle lesions, anti-PrPC staining detects a significantly broader spectrum of fibres than anti-vimentin or anti-NCAM. In dystrophic muscle, PrPC expression was mainly restricted to regenerating fibres. In IBM, PrPC expression was not confined to rimmed vacuoles or vacuolated fibres and only a small percentage (7.1%) of rimmed vacuoles were PrPC positive. Ultrastructurally, PrPC was observed in the cytoplasm of lymphocytes, in the myofibrillar network of targets, and in rimmed vacuoles. Knowledge of disease circumstances with altered expression of PrPC is important in the setting of a potentially increased chance for extraneural PrPC-PrPSc conversion. In addition, our observations suggest that PrPC may have a general stress-response effect in various neuromuscular disorders.

Chronic Disease↗

PubMed2004

Natively unfolded tubulin polymerization promoting protein TPPP/p25 is a common marker of alpha-synucleinopathies.

The novel basic, heat-stable tubulin polymerization promoting protein TPPP/p25 is associated with microtubules in vitro and can induce the formation of aberrant microtubule assemblies. We show by 1H-NMR spectroscopy that TPPP/p25 is natively unfolded. Antisera against peptide 186GKGKAGRVDLVDESG200NH2 (186-200) are highly specific to TPPP/p25. Immunohistochemistry and confocal microscopy demonstrates that TPPP/p25 is enriched in filamentous alpha-synuclein bearing Lewy bodies of Parkinson's (PD) and diffuse Lewy body disease (DLBD), as well as glial inclusions of multiple system atrophy (MSA). There is a correlation between TPPP/p25 and alpha-synuclein immunoreactivity in Western blot. In contrast, TPPP/p25 is not associated with abnormally phosphorylated tau in various inclusions of Pick's disease (PiD), progressive supranuclear palsy (PSP), and corticobasal degeneration (CBD). However, electron microscopy confirms clusters of TPPP/p25 immunoreactivity along filaments of unstructured but not compact neurofibrillary tangles in Alzheimer's disease (AD). TPPP/p25 seems to be a novel marker of alpha-synucleinopathies.

Aged↗

PubMed2004

Rationale for diagnosing human prion disease.

Human prion diseases (PrD) like Creutzfeldt-Jakob disease (CJD) include sporadic, acquired and familial neurodegenerative disorders. The central events in the neuropathological process of PrDs are severe neuronal loss, spongiform change and accumulation of abnormal prion protein (PrPSc). The latter is a conformational variant of the host-encoded cellular PrP (PrPC), a copper-binding protein. The physiological role of PrPC is debated. Definitive diagnosis of PrD is based on post mortem demonstration of PrPSc by immunohistochemistry or Western blot. Mutations in the PrP gene (PRNP), the polymorphic site at codon 129, and the molecular characteristic of protease resistant PrP influence the phenotype. Clinical symptoms, cranial MRI scan, EEG and investigation of 14-3-3 protein in cerebrospinal fluid (CSF) suggest a diagnosis of probable CJD. Variant CJD, related to bovine spongiform encephalopathy, shows a different clinical course, symmetrical high intensity MRI signal in the pulvinar, presence of PrPSc in tonsil biopsy tissue, and a lower sensitivity of CSF 14-3-3 protein compared to sporadic CJD. Future possibilities in diagnosis of PrDs include either the demonstration of PrPSc in body fluids or disease associated changes in laboratory variables or gene expression.

14-3-3 Proteins↗

PubMed2003

Fluorescent in situ hybridization on isolated tumor cell nuclei: a sensitive method for 1p and 19q deletion analysis in paraffin-embedded oligodendroglial tumor specimens.

In oligodendroglial neoplasms, losses of chromosomal material at 1p and 19q associate with chemosensitivity and prolonged survival. Thus, 1p/19q testing is increasingly proposed for use in brain tumor diagnosis and prognostic assessment. Fluorescent in situ hybridization (FISH) is a classic technique for investigation of 1p/19q status in paraffin-embedded tissues. A major limitation of this method is truncation of tumor cell nuclei complicating assessment of hybridization results. In our study, we analyzed 1p and 19q status in a series of 79 oligodendroglial neoplasms (49 oligodendrogliomas, 30 oligoastrocytomas, WHO: 57 Grade II, 22 Grade III tumors) and controls (gliotic brain tissue: n = 4, diffuse low-grade astrocytoma: n = 4) using FISH on isolated whole tumor cell nuclei, prepared as cytospin preparations, thus bypassing the problem of nuclear truncation. For interpretation of FISH results, we used consensus criteria as defined by the SIOP-Europe Neuroblastoma Study Group for analysis of peripheral neuroblastic tumors. FISH yielded interpretable results in 98.7% for 1p and 92.1% for 19q. Chromosome 1p/19q alterations comprised deletions (1p: 79.5%, 19q: 80%) and imbalances (1p: 11.5%, 19q: 12.9%). 1p aberrations were more frequent in oligodendroglioma than in oligoastrocytoma (100% versus 75.9%, P =.001). The frequency of 1p/19q alterations was not significantly different in WHO Grade II or Grade III tumors or in primary and recurrent tumors. We conclude that FISH on isolated cell nuclei, with application of the SIOP Europe Neuroblastoma consensus criteria, is a sensitive method for detection and interpretation of 1p and 19q aberrations in paraffin-embedded tissue specimens of oligodendroglial neoplasms.

Brain Neoplasms↗