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Biomedical subjects

M Becker

Publications and source records attributed to M Becker.

At least 469 records · Page 26Linked to original sources
PubMedDate not supplied

Modulation of proteoglycan metabolism by hydrocortisone and by growth factors in rhabdomyosarcoma cell lines of different metastatic potentials.

Glycosaminoglycans of cultured nickel-induced rat rhabdomyosarcoma cell lines with different metastatic potentials, grown in the presence or in the absence of hydrocortisone and of growth factor (EDF and EDGF) were investigated comparatively. The newly formed [35S]sulphate and [3H]glucosamine-labelled glycosaminoglycans were analysed in the extra-, peri- and intra-cellular compartments of the following cell lines: the strongly metastatic and colonizing 9-4/0 parental line, the very weakly metastatic and weakly colonizing subline 8 and the very weakly metastatic but colonizing subline 13a2. The cell surface of the weakly metastatic 8 and 13a2 lines was richer at least 5 and 2 times respectively in sulphated glycosaminoglycan label than the surface of the strongly metastatic 9-4/0 parental line. Hydrocortisone provoked an approximately four-fold increase in the label of the sulphated cell surface glycosaminoglycans of the 9-4/0 line. The pattern of the labelled cell surface glycosaminoglycans of these cells become similar to that of cells from the very weakly invading subline 8. Hydrocortisone induced only minor changes in the distribution of the glycosaminoglycans in the 8 and 13a2 lines, and at the same time, their proliferation rate and differentiation state was only slightly affected by this drug. Conversely to hydrocortisone, EGF increases the proliferation of the 9-4/0 line and also increases the label in sulphated cell surface glycosaminoglycans. This increase is about 50 per cent of that obtained by hydrocortisone. Thus, the accumulation of the glycosaminoglycan label on the cell surface is not directly related to the cell growth in the case of these cells. The results suggest that sulphated cell surface glycosaminoglycans, especially chondroitin sulphate, are involved in the inhibition of metastasis formation of the rhabdomyosarcoma cell lines studied.

Animals↗
PubMedDate not supplied

[Aneurysmal bone cyst of the ethmoid bone].

Aneurysmal bone cysts is a benign, slow growing expansile lesion usually found in long bones or vertebrae. Only 5 cases of ABC of the ethmoid bone have been reported in the literature. Plain radiographs are not specific. CT and MRI are very useful to depict the extent of the lesion and demonstrate the presence of blood-fluid levels, which is a characteristic finding of ABC. We present one atypical case of ABC of the ethmoid bone in a 15-year-old female characterised by its extensive involvement and its rare location.

Adolescent↗
PubMedDate not supplied

[Pappataci fever].

Sandfly fever virus is known to cause pappataci fever. The sandfly fever virus belongs to the Genus Phlebovirus (family: Bunyaviridae) and is endemically found in areas of South Europe, Asia and Africa. In Germany, pappataci fever is only described in connection with travelling to endemic areas. We report on a 15 year-old girl suffering from sandfly fever virus infection after vacation in Turkey. The initial symptoms started with fever for about three days, frontal headache, nausea and arthralgia. After a short time of clinical improvement symptoms recurred and our patient entered hospital with signs of severe meningitis. Liquor analysis showed a lymphocytic meningitis. Due to multiple insect bites on her legs sandfly fever was suspected. Blood analysis confirmed an acute infection with sandfly virus Sicilian from which she completely recovered. ELISA and immunoblot analysis revealed an infection with sandfly virus serotype Sicilian, which was not encountered with meningitis so far. Our case report illustrates that due to increased tourism sandfly fever virus infection has to be considered as a cause of aseptic meningitis in travellers.

Adolescent↗
PubMedDate not supplied

The stomach and pulmonary interlobular space as unusual sites of osteosarcoma.

The authors report a girl with high-grade intraosseous osteosarcoma of the left femur who lost one eye during early infancy for an unknown reason. Nine months after treatment, osteosarcoma in the stomach was detected and completely excised when the girl underwent endoscopy for Helicobacter pylori infection. Three years later osteosarcoma in the pulmonary interlobular space was noticed and completely removed. The girl is doing well and free of disease 26 months after the last resection.

Child↗
PubMedDate not supplied

Long-term changes induced by high-dose irradiation of the head and neck region: imaging findings.

High-dose irradiation is an effective treatment for tumors in the head and neck. Radiation-induced complications are uncommon but may result in chronic, progressive symptoms months or years after therapy. In 19 (1%) of 1,950 patients who underwent successful high-dose irradiation of head and neck tumors over a 5-year period, delayed radiation-induced changes were documented with imaging. These changes can be categorized as soft-tissue, bone, and cartilage necrosis; fibrosis leading to functional disorders; arteriopathy; central nervous system reactions, delayed myelopathy, and cranial nerve palsies; and the development of meningiomas. Radiologic features of radiation-induced soft-tissue, bone, and cartilage necrosis include inflammatory swelling adjacent to the area of involvement; deep gas-containing ulcerations; sclerotic appearance of the involved cartilages; fragmentation and sloughing of necrotic bone or cartilage; and abscess and fistula formation. Masticator muscle fibrosis appears as an area of diffusely increased signal intensity on T2-weighted images and of enhancement on postcontrast T1-weighted images. Radiation arteriopathy may manifest as occlusion, subocclusive sclerotic or atheromatous plaque, localized mural thrombus, aneurysm, or, rarely, spontaneous rupture. In central nervous system reactions, imaging findings include demyelination foci in the white matter, focal radiation necrosis, and severe brain atrophy. Radiation-induced meningiomas display the same imaging features as non-radiation-induced meningiomas at computed tomography, magnetic resonance imaging, and angiography, although follow-up examinations may reveal their more aggressive biologic behavior. Knowledge of the radiologic appearance of radiation-induced changes may prevent misinterpretations and facilitate treatment.

Aged↗
PubMedDate not supplied

Non-squamous cell neoplasms of the larynx: radiologic-pathologic correlation.

A variety of benign and malignant non-squamous cell neoplasms may affect the larynx. Most of these uncommon laryngeal neoplasms are located beneath an intact mucosa, making diagnosis difficult with endoscopy alone, and sampling errors may occur if only traditional superficial biopsies are performed. In some laryngeal neoplasms, radiologic evaluation allows the correct diagnosis. Hemangiomas have very high signal intensity at T2-weighted magnetic resonance (MR) imaging and strong enhancement at both computed tomography (CT) and MR imaging after administration of contrast material. Phleboliths, which are pathognomonic for hemangiomas, are easily identified at CT. Chondrogenic tumors typically manifest with coarse or stippled calcifications at CT. Because of their high water content, chondrogenic tumors have very high signal intensity on T2-weighted MR images, whereas only moderate enhancement is observed after administration of contrast material. Lipomas typically manifest at both CT and MR imaging as homogeneous nonenhancing lesions. They are isoattenuating to subcutaneous fat at CT and isointense relative to subcutaneous fat with all MR pulse sequences. Metastases from renal adenocarcinoma typically demonstrate strong contrast enhancement and flow voids at MR imaging, and metastases from melanotic melanoma usually have high signal intensity on T1-weighted MR images and low signal intensity on T2-weighted images owing to the paramagnetic properties of melanin. Although radiologic findings are nonspecific in most other non-squamous cell neoplasms of the larynx (eg, Kaposi sarcoma, hematopoietic tumors, tumors of the minor salivary glands, metastases from amelanotic melanoma), cross-sectional imaging can play an important role in the diagnostic work-up of these unusual tumors by delineating the extent of submucosal tumor spread and directing the endoscopist to the appropriate site for the deep, transmucosal biopsies needed to establish the diagnosis. In addition, CT and MR imaging are crucial for posttherapeutic monitoring and early detection of local recurrence.

Carcinoma, Squamous Cell↗
PubMedDate not supplied

Immunohistochemical detection of H-ras protooncoprotein p21 indicates favorable prognosis in node-negative breast cancer patients.

We tested primary breast carcinoma tissues from 297 patients using a monoclonal antibody (clone 235-1.7.1.) for the expression of p21(ras). 58% of tumors were p21(ras)-positive. When calculated in a univariate fashion, p21 expression correlated with proliferation activity (proliferating cell nuclear antigen) only. Using the log-rank test (median observation time 94 months) a significantly worse prognosis (disease-free survival, overall survival) relation was found with larger tumors, nodal involvement, anaplasia, rising proliferation activity, and lack of steroid receptors. Detection of p21(ras) correlated with a more favorable prognosis but only in node-negative patients. Stepwise correlation according to the Cox hazard model ranked p21 expression as a most significant predictor of prognosis second only to nodal status. These data suggest that detection of p21(ras) indicates the presence of a parameter which may act as tumor suppressor and benefit patients' survival.

Adult↗
PubMedDate not supplied

Prenatal diagnosis of common aneuploidies using multiplex quantitative fluorescent polymerase chain reaction.

OBJECTIVE: Prenatal diagnosis of foetal trisomies is usually performed by cytogenetic analysis. This requires lengthy laboratory procedures and it is expensive. Here, we report a retrospective study of quantitative fluorescent polymerase chain reaction (QF-PCR) for prenatal detection of trisomies 13, 18 and 21. METHODS: QF-PCR was performed on a total of 447 amniotic fluids blindly analysed without any knowledge of the cytogenetic results and 43 samples with known karyotype. All samples were tested with at least 4 small tandem repeat markers specific for each chromosome 13, 18 or 21. RESULTS: QF-PCR results on amniotic fluid were consistent with conventional cytogenetic data. QF-PCR detected 5 cases of trisomy 21, 2 cases of trisomy 18, 1 case of trisomy 13 and 1 case with Klinefelter's syndrome. CONCLUSIONS: QF-PCR has proved to be very useful in clinical settings, since it allows the detection of major numerical disorders in a few hours after sampling and thus reduces parental anxiety.

Aneuploidy↗
PubMedDate not supplied

Rare benign neoplasms of the larynx: rhabdomyoma and lipoma.

Two rare benign tumors of the larynx are presented. The first case is a recurrent multifocal rhabdomyoma, the second a lipoma of the larynx. Both tumors were growing beneath a normal-looking mucosa; deep biopsies were necessary to obtain a histologic diagnosis. Lipomas can be diagnosed by CT or MRI. A review of the literature of these two rare benign tumors is also presented.

Aged↗
PubMedDate not supplied

Effect of recombinant neutral endopeptidase (EC 3.4.24.11) on neuropeptide-mediated nasal fluid secretion and plasma exudation in the rat.

The nasal mucosa harbors sensory nerves containing neuropeptides such as substance P (SP), which are released by capsaicin. The neuropeptides are degraded by peptidases, e.g., neutral endopeptidase (NEP) that is present in the nasal mucosa. We studied the effect of enzymatically active recombinant NEP (rNEP) on neuropeptide-evoked secretion of nasal fluid and plasma exudation in rats. rNEP administered intranasally (i.n.) reduced the capsaicin-evoked nasal fluid secretion but failed to reduce the secretion evoked by SP (exogenous) under the experimental conditions used. rNEP reduced the increase in nasal plasma exudation evoked by capsaicin (endogenous neuropeptides). Because rNEP reduced neuropeptide-mediated nasal fluid secretion and plasma exudation in the rat, we suggest that peptidase activity in the nasal mucosa will determine the magnitude of the response to locally released neuropeptides.

Administration, Topical↗
PubMedDate not supplied

In vivo distribution and antitumour activity of liposomal 3',5'-O-dipalmitoyl-5-fluoro-2'-deoxyuridine.

3',5'-O-dipalmitoyl-5-fluoro-2'-deoxyuridine (FUdR-dipalmitate), a lipophilic prodrug of 5-fluoro-2'-deoxyuridine (FUdR), was incorporated in different types of liposomes. The in vivo distribution and intrahepatic deacylation of liposomal FUdR-dipalmitate was found to be strongly dependent on liposome composition and on drug to lipid ratio. The use of fluid-type liposomes (egg PC/PS/CHOL) rendered FUdR-dipalmitate more susceptible to enzymatic breakdown than solid-type liposomes (DSPC/DPPG/CHOL). A decrease of the retention of the drug in the body was also obtained when FUdR-dipalmitate was incorporated in solid-type liposomes with high drug to lipid ratio (1:10) than with low ratio (1:50). In spite of these substantial differences in the rates at which FUdR was liberated from liposomes with different fluidity, size, or drug to lipid ratio, only minor differences in therapeutic effect were observed in a number of murine tumour models (P388 leukaemia, Lewis Lung carcinoma, B16 melanoma and a C26 adenocarcinoma liver metastasis model). The lipophilic prodrug of FUdR exhibited antitumour activity at 100-600 times lower doses than the free drug. However, at these therapeutic doses FUdR-dipalmitate was also far more toxic. This prohibited the use of higher doses to increase antitumour activity.

Animals↗
PubMedDate not supplied

The PACS project in the radiology department of the LKH-Graz.

The PACS-project of Graz was started two years ago in cooperation with Siemens Erlangen. The system environment consists of three CT-devices (DR2, DR3, DRH) connected to an Ethernet-based LAN (CTnet), which is linked to a second Ethernet via a MicroVAX II. This computer works as a gateway, as an image-converter and as an archive. All CT-images of one device (DRH) are transmitted to the PACS system. The images are organized in patient-oriented folders. The physician is able to make reports about those examinations for which he is responsible. The availability of tools for secondary image processing during the reporting session (windowing, zooming, displaying statistic information, etc.) and further image-functions should make the PACS system more convenient for the physician than film-based images. After reporting, all scans which are relevant for the diagnosis (according to the physician's opinion) are selected, automatically reorganized in folders and transmitted to the archive. This needs about one to two minutes per examination. Some internal data-structures and further future aspects concerning the improvement of reliability and user acceptance are mentioned.

Database Management Systems↗
PubMedDate not supplied

H-ras gene amplification or mutation is not common in human primary breast cancer.

In a clinical study we found that patients with primary node negative breast cancer whose tumors showed high expression of H-ras had a significantly better prognosis than patients whose carcinomas did not. In the present study, these tissue specimens showed no H-ras gene mutation. The rate of gene amplification was 5% and did not correlate with the level of H-ras expression. These data indicate that increased expression and not amplification of the H-ras gene is valuable, if H-ras has a favorable role with respect to clinical outcome. This might be a general protective reaction as long as no mutation event has occurred in the H-ras gene.

Adult↗
PubMedDate not supplied

Expression of CD44 isoforms in human breast carcinoma xenografts is not influenced by the treatment of mice with cytostatics or (anti-)hormones.

CD44 standard (s) and variant (v) isoforms have been discussed to be implicated in progression and metastasis of different malignomas. For breast carcinomas, the results of different studies are contradictory. These apparent discrepancies suggest that CD44 isoforms are not available on the tumour cell surface, but could be regulated by different endogenous and exogenous factors. Here we report the regulation of CD44 isoforms in xenografted breast cancer cell lines by cytostatics, hormones and antihormones. The human breast cancer models MDA-MB 435, MCF-7, NCI/ADR, 4296, 4151 and 4134 were transplanted into the mammary fat pad of nude mice. When tumours reached a palpable size, animals were treated with farmorubicine, cyclophosphamide, estradiol, tamoxifen or progesterone, respectively. At different times after treatment, serum and tumours were taken. The expression of CD44 and its isoforms was determined by immunohistochemistry and RT-PCR, serum levels were measured by human specific ELISA kits. Serum levels of CD44s and v6 varied among the tumours. For 3/6 tumours we found differences between control groups and treated animals. Immunohistochemical results remained unchanged: each tumour showed a specific pattern of CD44 expression, but this pattern did not change when the animals received cytostatics, hormones or antihormones. The same held true for RT-PCR-results. Also, the time of tumour collection had no influence on CD44 expression. Therefore, it can be concluded, that in the xenografted breast cancer cell lines a regulation of CD44 isoforms by farmorubicine, cyclophosphamide, estradiol, progesterone or tamoxifen could not be found, while serum levels were influenced in some cases probably due to tumour cell kill and shedding of surface proteins into blood stream.

Animals↗
PubMedDate not supplied

Lack of correlation between P53 expression, BCL-2 expression, apoptosis and ex vivo chemosensitivity in advanced human breast cancer.

The relationship between apoptosis and chemosensitivity remains complex. We tested the chemosensitivity of 45 patients with advanced breast cancer (BC) ex vivo against anthracyclines (A: doxorubicin, epirubicin), taxanes (T: paclitaxel, docetaxel), cisplatin (DDP) and CMF and any correlation with the expression of p53, Bcl-2 and apoptosis. Viable cells were processed for ex vivo ATP Tumor Chemosensitivity Assay (ATP-TCA). Immunohistochemistry was performed in corresponding tumor samples. Apoptosis prior to chemotherapy was assayed using a TUNEL Test. Of 45 BC tested, 18 (40%) were p53+ and 37 (82%) showed high Bcl-2 expression. Apoptosis was detected in 29 (64.4%) specimens. The Ex vivo Response Rate (EVRR) for T was 75.6% in all cases. This was the highest rate among the 4 drugs tested followed by CMF (66.7%). For A and DDP the positive rates were lower (27.6% and 10.6%, respectively). A significant correlation (r = 0.589, p < or = 0.01) was found between tumors which were sensitive to A and DDP. There was no association between chemosensitivity and apoptosis. Moreover tests for p53 and Bcl-2 did not show a correlation to ex vivo chemosensitivity. Pretreatment apoptotic parameters are unlikely to predict the individual response of breast cancer to antineoplastic agents.

Antineoplastic Agents↗