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A Gschwendtner

Publications and source records attributed to A Gschwendtner.

At least 19 recordsLinked to original sources
PubMed2006

Brain volume changes in CADASIL: a serial MRI study in pure subcortical ischemic vascular disease.

BACKGROUND: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited small vessel disease causing stroke and subcortical vascular dementia. Recent studies in sporadic subcortical ischemic vascular disease have drawn attention to brain atrophy as a clinically important marker of disease progression. However, little is known about the role of brain atrophy and its clinical correlates in CADASIL. METHOD: The authors determined the normalized brain volume (NBV) and percent brain volume change (PBVC) over 2 years in 76 CADASIL subjects (45.1 +/- 9.7 years) using the SIENA (structural image evaluation using normalization of atrophy) software and its adaptation for cross-sectional measurements (SIENAX). Baseline assessments included systolic blood pressure (SBP), homocysteine levels, BMI, and APOE genotyping. T2-lesion volumes and clinical scales were assessed at both time points. RESULTS: The NBV significantly correlated with all clinical scores (Rankin, NIH Stroke Scale, Barthel, structured interview for the diagnosis of Alzheimer dementia and multi-infarct dementia, Mattis dementia rating scale) at both time points independently of age and sex. PBVC correlated with changes of all clinical scores (all p < 0.01) except for the Mattis dementia rating scale (p = 0.10). In a linear regression model, age (p < 0.001), male sex (p < 0.01), and SBP (p = 0.07) were the main risk factors for a lower NBV at baseline. Age (p < 0.001) and SBP (p = 0.01) were risk factors for brain volume loss during follow-up. Sample size estimates showed that the number of individuals needed to demonstrate a treatment effect in a trial can be reduced when PBVC is used as an endpoint. CONCLUSIONS: This study identifies brain atrophy as an important aspect of the disease process in CADASIL and establishes significant correlations with multiple clinical aspects including cognition. Age and systolic blood pressure are risk factors for brain volume loss during follow-up. Percent brain volume change seems promising as an adjunct outcome measure in future interventional trials.

Adult↗
PubMed2005

A patient with insidious onset of exertional dyspnoea.

The case history is presented of a 42 year old woman with pulmonary artery occlusion due to tuberculous vasculitis that masqueraded as chronic pulmonary artery embolism and led to severe life threatening haemoptysis necessitating emergency pneumonectomy. It is concluded that obliterative tuberculous endarteritis of the pulmonary arteries should be considered in the differential diagnosis of any acquired obstruction of pulmonary arteries.

Adult↗
PubMed2004

Characteristics of prostate cancers detected at low PSA levels.

BACKGROUND: When age-referenced PSA levels as recommended by Oesterling et al.1 were used as a biopsy criterion, only 25% of the cancers detected in a population based PSA Screening Project were organ-confined. This observation led to the decision to use low PSA levels as the sole indication for biopsy. Since 1995 age-referenced PSA levels of 1.25-3.25 ng/ml have been used in combination with a percentage free PSA cutoff of 18%. This PSA cutoff reduction led to a statistically significant migration to lower pathological stages with a decreased prostate cancer mortality in the years 1996-2001. However, concerns have been raised that screening with low PSA levels may detect clinically insignificant cancers. MATERIALS AND METHODS: We evaluated prostate cancer patients with low PSA levels in terms of heterogeneity, clinical significance, multifocality, and tumor biology including ploidy and proliferation index. RESULTS: Concerning heterogeneity the Gleason score of the needle biopsy failed to predict the Gleason score of the radical prostatectomy specimen in nearly 40% of prostate cancer patients; regarding multifocality 65% of patients with low PSA levels showed multifocal lesions and 36% exhibited tetraploid DNA distribution; more than 50% of tetraploid tumors were found in patients with tumor volumes of less than 0.5 cm(3). Ploidy correlated with the Ki-67 proliferation index, but not with tumor volume. CONCLUSIONS: These results demonstrate that small prostate cancers with low PSA levels and low tumor volumes exhibit all features of prostate cancers with higher tumor volumes and show the characteristics of malignant cancers, i.e., multifocality, tetraploidy, and high proliferative activity.

Adult↗
PubMed2001

Microglia and the early phase of immune surveillance in the axotomized facial motor nucleus: impaired microglial activation and lymphocyte recruitment but no effect on neuronal survival or axonal regeneration in macrophage-colony stimulating factor-deficient mice.

Activation of microglia is among the first cellular changes in the injured CNS. However, little is known about their specific contribution to secondary damage or repair processes in neighboring neurons and nonneuronal cells or to the immune surveillance of the damaged tissue. Animal models with defective microglial response such as osteopetrosis provide an approach to explore these effects. Osteopetrosis (op) is an autosomal recessive mutation with a complete deficiency of the macrophage-colony stimulating factor (MCSF; CSF-1), an important mitogen for brain microglia. In the current study we examined the effects of this MCSF deficiency on the microglial reaction and the overall cellular response to nerve injury in the mouse axotomized facial motor nucleus. In the brain, MCSF receptor immunoreactivity was found only on microglia and was strongly up-regulated following injury. MCSF deficiency led to a failure of microglia to show a normal increase in early activation markers (thrombospondin, MCSF receptor, alpha M beta 2- and alpha 5 beta 1-integrins), to spread on the surface of axotomized motoneurons, and to proliferate after injury. Early recruitment of CD3(+) T-lymphocytes to the facial nucleus 24 hours after injury was reduced by 60%. In contrast, the neuronal and astrocyte response was not affected. There was a normal increase in the neuropeptides calcitonin gene-related peptide and galanin, neuronal c-JUN, and NADPH-diaphorase and a decrease in choline acetyltransferase and acetylcholinesterase. Astrocyte glial fibrillary acidic protein immunoreactivity also showed a normal increase. There was a normal influx of macrophages and granulocytes into the injured facial nerve. Synaptic stripping, neuronal survival, and speed of axonal regeneration were also not affected. The current results show a strong, selective effect of MCSF on the early activation of microglia and, indirectly, on lymphocyte recruitment. This early phase of microglial activation appears not to be involved in the process of repair following peripheral nerve injury. However, it is important in the initiation of inflammatory changes in the brain and in the interaction with the immune system.

Animals↗
PubMed2001

Interleukin-6 (IL6) and cellular response to facial nerve injury: effects on lymphocyte recruitment, early microglial activation and axonal outgrowth in IL6-deficient mice.

Nerve injury triggers numerous changes in the injured neurons and surrounding non-neuronal cells. Of particular interest are molecular signals that play a role in the overall orchestration of this multifaceted cellular response. Here we investigated the function of interleukin-6 (IL6), a multifunctional neurotrophin and cytokine rapidly expressed in the injured nervous system, using the facial axotomy model in IL6-deficient mice and wild-type controls. Transgenic deletion of IL6 caused a massive decrease in the recruitment of CD3-positive T-lymphocytes and early microglial activation during the first 4 days after injury in the axotomized facial nucleus. This was accompanied by a more moderate reduction in peripheral regeneration at day 4, lymphocyte recruitment (day 14) and enhanced perikaryal sprouting (day 14). Motoneuron cell death, phagocytosis by microglial cells and recruitment of granulocytes and macrophages into injured peripheral nerve were not affected. In summary, IL6 lead to a variety of effects on the cellular response to neural trauma. However, the particularly strong actions on lymphocytes and microglia suggest that this cytokine plays a central role in the initiation of immune surveillance in the injured central nervous system.

Animals↗
PubMed2001

Primary gastrointestinal B-cell lymphoma. A clincopathological and immunohistochemical study of 61 cases with an evaluation of prognostic parameters.

We hereby present a retrospective clinicopathological and immunohistochemical study of surgically resected primary gastrointestinal (GI) lymphoma with an analysis of parameters of potential prognostic relevance. From a larger series of 144 cases of primary GI lymphomas, we chose 61 cases with sufficient clinical follow-up (mean 60, range 1-219 months), classified either as extranodal marginal zone B-cell lymphoma of MALT type (MALT lymphoma) or diffuse large B-cell lymphoma (DLBCL), after having excluded other subtypes. In addition to conventional clinical and morphological parameters, the expression levels of Ki-67 (MIB-1), bcl-2 and p53 were evaluated for prognostic significance. Twenty-one (34.4%) cases were classified as pure low grade marginal zone B-cell lymphoma of MALT type, 12 (19.7%) cases as low grade MALT lymphoma with a high grade component (mixed type), and 28 (45.9%) cases as primary extranodal DLBCL. Most of the lymphomas (53/61; 86.9%) were localized in the stomach, 3 (4.9%) in the small bowel, 3 (4.9%) multifocal in both stomach and small intestine and 2 (3.3%) in the large bowel. MIB-1 expression in more than 30% of tumor cells was detected in 42 (68.6%), bcl-2 expression in 20 (32.8%) and p53 accumulation in more than 10% of neoplastic cells in 16 (26.2%) lymphomas. Both high Ki-67 expression and p53 accumulation were more prevalent in the DLBCL. 30 (49%) patients showed lymph node involvement at surgery, 14 (23%) patients suffered tumor recurrence, and 24 (38.5%) died during the follow-up period. Tumor recurrence occurred primarily in patients who had presented lymph node involvement (9/14, 64.3%). The 5-year survival rate was 66.1% for all patients. Important prognostic factors for overall survival were tumor stage (p < .004) and p53 accumulation (p < .05) in univariate analysis, and tumor stage in multivariate analysis (p < .001). Although p53 accumulation did not reach statistical significance in our small study group, it may be both important in the transformation of low grade MALT lymphoma and an indicator for aggressive behavior in high grade tumors.

Adult↗
PubMed2001

Fourth updated ESACP consensus report on diagnostic DNA image cytometry.

A task force of experts in the field of diagnostic DNA image cytometry, invited by the ESACP, and further scientists or physicians revealing experience in that diagnostic procedure (names are given in Addendum A), agreed upon the following 4th updated Consensus Report on Standardised Diagnostic DNA Image Cytometry during the 7th International Congress of that society in Caen, 2001. This report is based on the three preceding ones [6,14,17]. It deals with the following items:- Critical review and update of the definitions given in the 1997 Consensus Update;- Review and detailed description of basic terms, principles and algorithms for diagnostic interpretation;- Recommendations concerning diagnostic or prognostic applications in specific fields of tumour pathology. This update is not aimed to substitute the 1997 consensus, but to make necessary addenda and give more detailed descriptions of those items not unequivocally to interpret by potential users of the methodology.

Algorithms↗
PubMed2000

Optimized preembedding method improves the histologic yield of prostatic core needle biopsies.

BACKGROUND: The aim of this study was to optimize the core shape of prostatic core needle biopsies using a novel preembedding method, and to investigate the influence of the number of cores per tissue block on the histologic yield per section level. METHODS: Twenty-four core needle biopsies were taken from a fresh prostatectomy specimen, using an 18-gauge needle. Twelve core needle biopsies were conventionally fixed floating free in formalin-filled containers, whereas 12 biopsies were stretched between two nylon meshes, and placed in tissue cassettes before fixation. The total number of tissue sections per paraffin block necessary for complete workup of the tissue was determined. Using image analysis, the relation of the area of every fifth section level was calculated in relation to the total projected area of the biopsies. Both methods of tissue processing were compared for both parameters. RESULTS: In contrast to the curved biopsies after conventional processing, the optimized preembedding method generally led to stretched cores after fixation and embedding. This method led to a 100% decrease in total number of tissue sections necessary for complete workup and to higher percentages of the tissue amount per section level compared to the total projected core area. These parameters were also influenced by the number of cores per paraffin block, but to a minor degree. CONCLUSIONS: This study shows that optimized preembedding of prostatic needle biopsies improves the histologic yield per section level. The continuous occurrence of representative sections could improve diagnostic accuracy in the histological examination of prostatic core needle biopsies.

Biopsy, Needle↗
PubMed2000

[Value of bronchoalvoeolar lavage in the diagnosis of lung disease].

Bronchoalveolar lavage (BAL) is an important tool for evaluating interstitial lung diseases. It provides information on inflammatory cells which play an important role in the pathogenesis of such diseases and complements the information of the lung biopsy. The method is based on the observation, that the cells recovered by BAL reflect the population of cells in pulmonary parenchyma. In healthy subjects the main cells in the lavage fluid are macrophages (> or = 80%), lymphocytes (10-20%), some few neutrophils (< or = 4%), eosinophils (< or = 3%) and single mast cells. There are significant differences in the distribution of cell types in never-smokers, exsmokers and current smokers. Generally the increase in the number of lymphocytes is a hallmark of granulomatous and allergic lung diseases. Evaluation of the lymphocyte surface antigen phenotypos allows the recognition of sarcoidosis (increased proportion of T-helper lymphozytes) and extrinsic allergic alveolitis (increased proportion of T-suppressor lymphocytes). High neutrophil counts are characteristic of fibrosing processes or of occupational diseases caused by inhalation of inorganic dust. The evaluation of the diagnostic accuracy of the BAL is difficult because the final diagnosis of many symptomatically cured patients is not clear. Nevertheless, the evaluation of our cases showed a surprisingly high overall diagnostic accuracy (> 80%). However, the accuracy of negative diagnosis (exclusion of a certain disease) is slightly higher than this of the positive ones (diagnosis confirmed).

Bronchoalveolar Lavage↗
PubMed1999

Underestimated health hazard: proposal for an ergonomic microscope workstation.

Working daily for a long time with a standard microscope causes back pain, fibromyalgia, or tension headache in up to 80% of microscopists. These complaints may be prevented by an ergonomic design of the microscope workstation, leading to a beneficial and significant reduction of electromyographical activity in the most strained muscle groups as shown by surface electromyographic recordings.

Adult↗
PubMed1999

Nuclear chromatin texture analysis of nonmalignant tissue can detect adjacent prostatic adenocarcinoma.

BACKGROUND: The aim of this study was to investigate the possibility of identifying prostatic adenocarcinoma by nuclear chromatin texture feature analysis of adjacent histologically benign-looking tissue. METHODS: Two hundred and forty prostatectomy specimens were selected from the archives of the Department of Pathology, University of Innsbruck. These consisted of 67 cases of benign prostatic hyperplasia (BPH) and 173 cases of prostatic adenocarcinoma (PAC). The specimen collection was divided randomly into a training set and test set. Cytospin preparations of disaggregated cells prepared from paraffin-embedded material were stained specifically for DNA by the Feulgen method. For the cancer cases, only tissue that histologically appeared nonmalignant, from the vicinity of the lesion, was used in the sample preparation. Only normal-appearing diploid cell nuclei were analyzed from both the BPH and PAC groups. A discriminator comprised of three nuclear texture features to separate BPH from PAC cases was derived from the training set of cases, and then applied to the independent test set cases. RESULTS: PAC cases were separated from BPH cases with a sensitivity of 90% and a specificity of 97% on the independent test set of cases. CONCLUSIONS: This retrospective investigation demonstrates that by high-resolution image cytometry it is possible to detect the presence of prostatic adenocarcinoma with very high reliability when examining prostate samples that only contain histologically normal-looking cells. This method could become clinically relevant in identification of cancers missed by histologically negative core needle biopsies.

Adenocarcinoma↗
PubMed1999

Quantitative assessment of bladder carcinoma by acid labile DNA assay.

BACKGROUND: Effective noninvasive methods for monitoring patients with bladder carcinoma and screening for bladder carcinoma that show better performance than the methods currently in use would be desirable for detecting urothelial carcinoma at an early, easily treatable stage. A rapidly hydrolyzed component of nuclear DNA has been described, the increase of which has been linked to malignancy. Quantitative determination of acid labile DNA has been applied successfully to detect other neoplasms. This study investigates the potential of this method to detect transitional cell carcinomas. METHODS: Touch imprints of transurethral resection material from 62 cases of nonmalignant urothelium (control group including reactive changes) and 94 cases of bladder carcinoma were analyzed. The full Feulgen hydrolysis profiles of the nonmalignant and malignant urothelial cells were compared by measuring the staining density of the nuclei using digital image analysis after various hydrolysis times. Twenty cells were sampled randomly from among the cells measured for calculation of the mean optical density (MOD). The MOD of each time was used to build the hydrolysis profile of a case. RESULTS: A hydrolysis time of 10 minutes was found to be the most discriminative between control and carcinoma cases. Applying a single threshold MOD value of 101 resulted in a test sensitivity of 95.7%, a specificity of 94.4%, a positive predictive value of 98.3%, a negative predictive value of 95.9%, and an area under the receiver operating characteristic curve of 0.97. CONCLUSIONS: The results of this pilot study suggest that measurement of the rapidly hydrolyzed component of DNA present in the nuclei of bladder urothelium offers a highly sensitive and reliable supplement to the qualitative and subjective cytologic procedures currently in use.

Carcinoma, Transitional Cell↗
PubMed1999

Septicaemia and endomyocarditis caused by Aerococcus urinae.

Aerococcus urinae, an uncommon urinary tract pathogen, was recently shown to cause septicaemia and endocarditis in a few patients in Denmark and the Netherlands. In Austria this is the first report of a fatal course of endomyocarditis by Aerococcus urinae, associated with multiple septic infarcts.

Adult↗
PubMed1999

DNA-ploidy analysis correlates with the histogenetic classification of thymic epithelial tumours.

The ploidy values of the epithelial component were determined in a series of thymomas and organotypic thymic carcinomas using image cytometry and the results were compared with the histological tumour subtypes according to the histogenetic classification introduced by Marino, Müller Hermelink, and Kirchner (MMHK). Forty-six cases of thymic epithelial tumours were included in the study. After reclassification according to the MMHK classification, the distribution among the subtypes was as follows: three medullary, nine mixed type, five predominantly cortical (organoid), 16 cortical thymomas, and 13 well-differentiated thymic carcinomas. Single cell preparations were made from paraffin-embedded tumour tissue and stained according to Feulgen. Ploidy analysis was performed using an automated image analysis system. In five cases, DNA cytometry could not be performed, for technical reasons. The remaining 41 cases consisted of 11 diploid and 30 non-diploid tumours. The percentage of aneuploid tumours in the different subtypes increased from medullary (0 per cent) through mixed type (44.4 per cent), predominantly cortical (75 per cent), cortical (83.3 per cent) to well-differentiated thymic carcinomas (100 per cent). DNA-ploidy determination using image cytometry correlates with the concept of the MMHK classification of thymomas.

Humans↗
PubMed1999

Are nuclear texture features a suitable tool for predicting non-organ-confined prostate cancer?

PURPOSE: We investigated the possibility of determining organ confinement of prostate cancer using multiple nuclear texture features determined by fully automated high resolution image analysis combined with preoperative serum PSA levels. MATERIALS AND METHODS: The study population consisted of 145 patients (61 organ confined and 84 non-organ-confined cases). Nuclear texture features were determined using single cell preparations of radical prostatectomy specimens. Nuclear texture features were extracted and analyzed by multivariate logistic regression analysis in order to build a classifier for distinguishing between organ confined and non-organ-confined tumors. The classifier was designed in a cell by cell model and tested on a case by case analysis. RESULTS: The predictive probability of the trained classifier in the cell by cell analysis had a sensitivity of 63%, a specificity of 53%, a positive predictive value of 75% and a negative predictive value of 38% and an area under the ROC curve of 0.58. In the case by case analysis the sensitivity was 70%, the specificity was 54%, positive predictive value 78%, negative predictive value 74%, area under the ROC curve 0.62. When preoperative PSA was included in the algorithm, sensitivity raised to 80%, specificity to 60%, the positive predictive value raised to 79%, the negative predictive value to 52% and the area under the ROC curve to 0.70. CONCLUSIONS: In contrast to former studies using tissue sections, our results suggest that nuclear texture features extracted from single cell preparations cannot be used as a reliable parameter for the determination of organ confinement in prostatic adenocarcinomas.

Adenocarcinoma↗
PubMed1999

Quantitative assessment of bladder cancer by nuclear texture analysis using automated high resolution image cytometry.

The aim of this study was to investigate the possibility of identifying urothelial neoplasia by nuclear chromatin texture feature analysis using high resolution image cytometry to improve the diagnostic accuracy of cytologic examination in the detection and monitoring of bladder cancer. Touch imprints of transurethral resection material of 56 control group (CG) cases of nonmalignant urothelium and 94 tumor group (TG) cases of bladder cancer were analyzed. The specimen collection was divided randomly into a training set and a test set. Cells were stained specifically for DNA by the Feulgen method. Only diploid cell nuclei were analyzed from both groups. A discriminator comprised of three nuclear texture features was derived from the training set of cases to separate CG from TG cases. This discriminator was then applied to the independent test set. CG cases were separated from TG cases with a sensitivity of 97% and a specificity of 95% on the independent test set of cases. When dividing TG cases into high-risk and low-risk groups, sensitivity in the low-risk group was 93%. None of the high-risk cases was misclassified (sensitivity, 100%). This retrospective investigation demonstrates that by high-resolution image cytometry it is possible to distinguish between urothelial neoplasia and normal urothelium with high reliability when examining diploid cell nuclei only. This method is superior to DNA ploidy analysis using image or flow cytometry and may become clinically relevant as a supplement to conventional cytologic examination. These promising results should be confirmed on cytologic preparations derived from bladder washings or voided urine.

Adult↗