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1.
HNO ; 67(4): 251-257, 2019 Apr.
Article in German | MEDLINE | ID: mdl-30887062

ABSTRACT

Increasing numbers of cochlear implant patients have residual hearing. Despite surgical and pharmacological efforts to preserve residual hearing, a significant number of these patients suffer a late, unexplained loss of residual hearing. Surgical trauma can be excluded as the cause. To investigate this phenomenon and because cells in their native environment react differently to stimuli (such as electrical current) than isolated cells, whole-organ explants from cochleae may be a better model. For early detection of synaptic changes in the organ of Corti, a high-resolution microscopic technique such as stimulated emission depletion (StED) can be used. The aim of this study was establishment of a qualitative and quantitative technique to determinate changes in the organ of Corti and its synapses after electrical stimulation. Explanted organs of Corti from postnatal rats (P2-4) were cultured on a coverslip for 24 h and subsequently exposed to biphasic pulsed electrical stimulation (amplitude 0.44-2.0 mA, pulse width 400 µs, interpulse delay 120 µs, repetition 1 kHz) for another 24 h. For visualization, the cytoskeleton and the ribbon synapses were stained immunocytochemically. For an early detectable response to electrical stimulation, the number of synapses was quantified. Organs of Corti without electrical stimulation served as a reference. Initial research has shown that electrical stimulation can cause changes in ribbon synapses and that StED can detect these alterations. The herein established model could be of great importance for identification of molecular changes in the organ of Corti in response to electrical or other stimuli.


Subject(s)
Cochlea , Electric Stimulation Therapy , Hearing Loss/prevention & control , Organ of Corti , Animals , Cochlear Implantation , Electric Stimulation , Hearing , Humans , Organ of Corti/cytology , Organ of Corti/ultrastructure , Rats
2.
Eye (Lond) ; 25(12): 1627-34, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21921959

ABSTRACT

PURPOSE: To evaluate the optical and anatomical effects of oral propranolol treatment for infantile periocular capillary haemangioma. METHODS: All children diagnosed with infantile capillary haemangioma in 2008-2010 at a tertiary paediatric medical centre underwent comprehensive evaluation, including imaging, by a multidisciplinary team followed by oral propranolol treatment. Clinical follow-up was performed regularly until the lesions disappeared. Main outcome measures included changes in anatomical extraocular extension, refractive sphere and cylindrical power, and spherical equivalent in the involved eye before and after treatment and between the two eyes. RESULTS: A total of 30 patients (8 male; mean age at diagnosis, 1.6±2.8 months) participated. The lesions affected the left eye in 53.3% and were located preseptally in 83.3%. Four patients (13.3%) received steroids before propranolol. A treatment dosage of 2 mg/kg per day was started at mean age 5.0±4.5 months, 3.3±4.3 months from disease onset. Side effects occurred in 11 patients and warranted a dose reduction (to 1 mg/kg per day) in 3 and treatment termination in 1. Findings were significant for mean reduction in involved extraocular area (P<0.0001), post-treatment reduction in mean cylindrical power in involved eyes (P=0.02), pre- and post-treatment differences in mean cylindrical power between involved and uninvolved eyes (P=0.02 and P=0.01, respectively), and post-treatment change in absolute values of mean spherical power between involved and uninvolved eyes (P=0.025). CONCLUSIONS: Early diagnosis of infantile periocular capillary haemangioma and prompt treatment with propranolol lead to a significant reduction in the involved ocular area, in astigmatism, and prevent ocular/facial disfiguration/deformation, without rebound. Propranolol is recommended as the preferred treatment compared with other accepted therapies.


Subject(s)
Adrenergic beta-Antagonists/therapeutic use , Eyelid Neoplasms/drug therapy , Hemangioma, Capillary/drug therapy , Neoplastic Syndromes, Hereditary/drug therapy , Orbital Neoplasms/drug therapy , Propranolol/therapeutic use , Refraction, Ocular/physiology , Eyelid Neoplasms/pathology , Eyelid Neoplasms/physiopathology , Female , Hemangioma, Capillary/pathology , Hemangioma, Capillary/physiopathology , Humans , Infant , Male , Neoplastic Syndromes, Hereditary/pathology , Neoplastic Syndromes, Hereditary/physiopathology , Orbital Neoplasms/pathology , Orbital Neoplasms/physiopathology , Retrospective Studies
3.
Nervenarzt ; 77(5): 587-95, 2006 May.
Article in German | MEDLINE | ID: mdl-15965760

ABSTRACT

In order to evaluate risk assessment instruments for sex offenders in Germany, we compared the predictive validity of the Static-99, HCR-20, SVR-20, and PCL-R scales for 134 sex offenders. The mean follow-up time was 9 years (range 1-340 months), using the first entry into the National Register of Criminal Convictions as endpoint variable. For the estimate of predictive power, the area under the curve (AUC) of receiver operating characteristic (ROC) analysis was calculated. The AUC plots accurately identified violent or sexual recidivists and "false positives" at all scale levels. Comparing the predictive validity of these four instruments, the results favored Static-99. As for the limited sample size, differences between the assessment instruments were, however, not statistically significant. The ROC analysis for Static-99 showed that including treatment dropouts does not improve predictive accuracy (including dropouts: AUC 0.710; excluding dropouts: AUC 0.721). Kaplan-Meier survival analyses yielded highly a significant correlation to recidivism time point for two Static-99 and SVR-20 risk categories. Higher-risk categories were related to earlier recidivism. However, relying on the Static-99 and SVR-20 alone showed false positive results: for up to two out of three sex offenders, they predicted recidivism which did not occur.


Subject(s)
Forensic Psychiatry/methods , Psychological Tests/statistics & numerical data , Risk Assessment/methods , Sex Offenses/psychology , Sex Offenses/statistics & numerical data , Germany/epidemiology , Humans , Prognosis , ROC Curve , Reproducibility of Results , Risk Factors , Sensitivity and Specificity , Sex Offenses/prevention & control , Violence/psychology , Violence/statistics & numerical data
4.
Diagn Mol Pathol ; 8(2): 66-70, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10475380

ABSTRACT

Tumor cells in abdominal lavage specimens from patients with gastric carcinoma strongly predict subsequent peritoneal metastasis and poor prognosis. Reverse transcription (RT)-polymerase chain reaction (PCR) detection of wild-type E-cadherin has been claimed to be superior to conventional cytology for the detection of patients who subsequently develop peritoneal metastases. The present study tested this hypothesis and determined whether or not the detection of mutated, tumor-specific E-cadherin messenger RNA in abdominal lavage specimens serve as a useful diagnostic tool. Preoperative lavage specimens from 52 patients with diffuse-type gastric carcinoma and from 5 patients with benign disease were analyzed by conventional cytology and by RT-PCR for amplification of E-cadherin. Tumor cells were detected by cytology in 8 (15.3%) of the 52 patients with gastric cancer. The E-cadherin was detected in all 57 samples by RT-PCR. Two of these had abnormal E-cadherin amplification products confirmed to be mutations by direct sequencing, which were identical in the primary tumors. These findings suggest that the detection of wild-type E-cadherin is not sufficiently tumor specific. Also, for diffuse gastric carcinomas with confirmed E-cadherin mutations, detection of mutant E-cadherin by RT-PCR is a potentially valuable method for tumor cell detection in lavage specimens.


Subject(s)
Cadherins/genetics , Carcinoma/genetics , Peritoneal Lavage , Stomach Neoplasms/genetics , Ascitic Fluid/cytology , Cadherins/metabolism , Carcinoma/metabolism , Carcinoma/pathology , DNA Mutational Analysis , DNA, Complementary/genetics , Exons , Humans , Mutation , RNA, Messenger/genetics , Reverse Transcriptase Polymerase Chain Reaction , Sensitivity and Specificity , Sequence Deletion , Stomach Neoplasms/metabolism , Stomach Neoplasms/pathology
5.
Oncogene ; 18(30): 4301-12, 1999 Jul 29.
Article in English | MEDLINE | ID: mdl-10439038

ABSTRACT

A major function of the cell-to-cell adhesion molecule E-cadherin is the maintenance of cell adhesion and tissue integrity. E-cadherin deficiency in tumours leads to changes in cell morphology and motility, so that E-cadherin is considered to be a suppressor of invasion. In this study we investigated the functional consequences of three tumour-associated gene mutations that affect the extracellular portion of E-cadherin: in-frame deletions of exons 8 or 9 and a point mutation in exon 8, as they were found in human gastric carcinomas. Human MDA-MB-435S breast carcinoma cells and mouse L fibroblasts were stably transfected with the wild-type and mutant cDNAs, and the resulting changes in localization of E-cadherin, cell morphology, strength of calcium-dependent aggregation as well as cell motility and actin cytoskeleton organization were studied. We found that cells transfected with wild-type E-cadherin showed an epitheloid morphology, while all cell lines expressing mutant E-cadherin exhibited more irregular cell shapes. Cells expressing E-cadherin mutated in exon 8 showed the most scattered appearance, whereas cells with deletion of exon 9 had an intermediate state. Mutant E-cadherins were localized to the lateral regions of cell-to-cell contact sites. Additionally, both exon 8-mutated E-cadherins showed apical and perinuclear localization, and actin filaments were drastically reduced. MDA-MB-435S cells with initial calcium-dependent cell aggregation exhibited decreased aggregation and, remarkably, increased cell motility, when mutant E-cadherin was expressed. Therefore, we conclude that these E-cadherin mutations may not simply affect cell adhesion but may act in a trans-dominant-active manner, i.e. lead to increased cell motility. Our study suggests that E-cadherin mutations affecting exons 8 or 9 are the cause of multiple morphological and functional disorders and could induce the scattered morphology and the invasive behaviour of diffuse type-gastric carcinomas.


Subject(s)
Actins/ultrastructure , Cadherins/genetics , Cell Adhesion , Cell Movement , Mutation , Stomach Neoplasms/genetics , Animals , Cadherins/metabolism , Exons , Fibroblasts/cytology , Fluorescent Antibody Technique , Humans , Mammary Neoplasms, Animal/genetics , Mice , Microscopy, Confocal , Models, Genetic , Point Mutation , Stomach Neoplasms/pathology , Transfection , Tumor Cells, Cultured , Wound Healing
6.
J Pathol ; 187(2): 164-72, 1999 Jan.
Article in English | MEDLINE | ID: mdl-10365091

ABSTRACT

Rhabdomyosarcomas bear a morphological and genetic resemblance to developing skeletal muscle. Apart from myogenic marker genes (bHLH factors, myosin, actin), cell adhesion molecules such as N-cadherin and N-CAM have been reported to be expressed both in rhabdomyosarcomas and during myogenesis. The present study demonstrates the expression of another cadherin, cadherin-11, in rhabdomyosarcomas and during differentiation of myoblasts in vitro: cadherin-11, a predominantly mesenchymal cell adhesion molecule, is highly expressed in embryonal rhabdomyosarcomas and alveolar rhabdomyosarcomas, which do not bear the Pax-3-FKHR fusion previously described. Cadherin-11 is down-regulated in normal skeletal muscle and after myotube formation in vitro. The results of this study suggest that cadherin-11 might be involved in myogenesis and that rhabdomyosarcomas may re-express or fail to down-regulate cadherin-11. Since alveolar rhabdomyosarcomas bearing the t(2;13) translocation do not express cadherin-11, it is postulated that Pax-3 and cadherin-11 might be linked and involved in the same myogenic pathway.


Subject(s)
Cadherins/metabolism , Muscle, Skeletal/metabolism , Neoplasm Proteins/metabolism , Rhabdomyosarcoma/metabolism , Animals , Blotting, Northern , Blotting, Western , Cell Culture Techniques , Cell Differentiation/physiology , Child , Fluorescent Antibody Technique , Humans , Mice , Mice, Inbred CBA , Muscle, Skeletal/cytology , Tumor Cells, Cultured
7.
Hum Mutat ; 13(2): 171, 1999.
Article in English | MEDLINE | ID: mdl-10094558

ABSTRACT

The cell adhesion molecule E-cadherin (CDH1; MIM# 192090) has been implicated in numerous cellular functions, ranging from controlling morphogenesis to suppressing tumor invasion. We describe 11 previously unreported somatic E-cadherin mutations in two subgroups of gastric and breast cancer showing markedly reduced homophilic cell-to-cell interactions. Using reverse transcription-polymerase chain reaction (RT-PCR) and direct sequencing of the entire coding region 5 mutations were detected in diffuse-type gastric cancer specimens. The sequence alterations include 3 missense mutations affecting exons 3, 10, and 12. Furthermore, two in-frame deletions were identified removing 63 and 9 base pairs from exon 4 and 5, respectively. In invasive Lobular breast cancer 6 E-cadherin mutations were detected after RT-PCR amplification and direct sequencing or using single strand conformation polymorphism (SSCP) analysis followed by sequencing. In addition to two nonsense mutations affecting exon 2, four out-of-frame deletions removing 115 base pairs (entire exon 2), 224 base pairs (entire exon 3), 8 base pairs from exon 12 or 1 base pair from exon 13 were seen. Our report confirms the general principle that in diffuse-type gastric cancer E-cadherin mutations result in structurally altered proteins with possible reduced adhesive functions whereas in invasive lobular breast carcinomas complete loss-of-function mutations are characteristic.


Subject(s)
Breast Neoplasms/genetics , Cadherins/genetics , Mutation/genetics , Stomach Neoplasms/genetics , Humans , Polymorphism, Single-Stranded Conformational , Reverse Transcriptase Polymerase Chain Reaction
8.
Pathologe ; 18(2): 124-30, 1997 Mar.
Article in German | MEDLINE | ID: mdl-9244870

ABSTRACT

The frequency and prognostic relevance of sarcoid-like lesions and microcarcinosis in regional lymph nodes in gastric cancer (n = 113; pT1-3, pN0-1, pM0, R0) were investigated; the prognostic value was compared with pT and pN stage, grading and Laurén's tumor classification with Cox's multivariate regression-model. Sarcoid like lesions were found in 34% of the cases (n = 113). Statistical analysis did not indicate that they had any prognostic value or showed whether or not microcarcinosis or metastasis was present; they were independent of pT stage, histological tumor type, tumor grading, and the clinical course of disease. Microcarcinosis (defined as scattered carcinoma cells within lymph node sinuses or pulp without adjacent stromal reaction) was revealed by immunohistochemistry in 90% of pN0 cases; the presence of 3 or more tumor cells per lymph node section in over 10% of sampled lymph nodes per case carried a significant prognostic value. In microcarcinosis without evidence of metastasis, the number of tumor cells and the number of involved lymph nodes are of prognostic value. In pN1 cases microcarcinosis was found as well as the metastases in 97% and had no additional prognostic value. Microcarcinosis alone has a different significance from lymph node metastasis for prognosis.


Subject(s)
Adenocarcinoma/pathology , Lymph Nodes/pathology , Adenocarcinoma/surgery , Biomarkers, Tumor/analysis , Epithelium/pathology , Humans , Immunoenzyme Techniques , Lymph Node Excision , Lymph Nodes/surgery , Lymphatic Metastasis , Neoplasm Staging , Prognosis , Spleen/pathology , Splenic Neoplasms/pathology , Splenic Neoplasms/secondary , Stomach/pathology
9.
J Orofac Orthop ; 57(4): 246-58, 1996 Aug.
Article in English, German | MEDLINE | ID: mdl-8765800

ABSTRACT

The subject of this study is an analysis of the possible specific ethnic characteristics of the craniofacial morphology within the Saxon population. For this purpose we analyzed, in a cephalometric cross-sectional study, lateral cephalometric radiographs taken between 1992 and 1994 of 10,047 orthodontically untreated native Saxon patients. The cephalometric analysis used was a synthesis of several classic procedures as applied at Leipzig University. Among the sagittal parameters there was a relatively high prevalence of mandibular retrognathism and skeletal distal jaw relationship. The vertical parameters displayed a relatively good balance between vertical and horizontal growth patterns. With respect to sexual dimorphism, the differences in the angular parameters and in the indices of relationship were only moderate and so almost irrelevant in clinical terms. Among the age-related changes, the focus is on the increase in the degree of prognathism of both jaws and the anterior rotation of the mandible.


Subject(s)
Facial Bones/anatomy & histology , Orthodontics , Skull/anatomy & histology , Adolescent , Adult , Aging , Cephalometry/statistics & numerical data , Child , Child, Preschool , Facial Bones/diagnostic imaging , Female , Germany , Humans , Male , Orthodontics/statistics & numerical data , Radiography , Reference Values , Sex Characteristics , Skull/diagnostic imaging , White People
11.
Hum Genet ; 96(6): 739-40, 1995 Dec.
Article in English | MEDLINE | ID: mdl-8522339

ABSTRACT

We report four DNA variants in the gene coding for the cell adhesion molecule E-cadherin. The polymorphisms affect codons 115, 133, 582 and the 3'-non-coding region.


Subject(s)
Cadherins/genetics , Genetic Variation , Polymorphism, Genetic , Alleles , Base Sequence , Codon , DNA Primers , Gastric Mucosa/metabolism , Gene Frequency , Humans , Molecular Sequence Data , Polymerase Chain Reaction , Stomach Neoplasms/genetics
13.
Cancer Res ; 54(14): 3845-52, 1994 Jul 15.
Article in English | MEDLINE | ID: mdl-8033105

ABSTRACT

The calcium-dependent homophilic cell adhesion molecule and candidate suppressor gene, E (epithelial)-cadherin, plays a major role in the organization and integrity of most epithelial tissues. Diffusely growing gastric carcinomas show markedly reduced homophilic cell-to-cell interactions. We speculated that mutations in the E-cadherin gene may be responsible for the scattered phenotype of this type of carcinoma. For that reason we have examined E-cadherin in 26 diffuse type, 20 intestinal type and 7 mixed gastric carcinomas (Laurén's classification) at the DNA, RNA, and protein levels. Reverse transcription polymerase chain reaction and direct sequencing of amplified E-cadherin complementary DNA fragments revealed inframe skipping of either exon 8 or exon 9 in 10 patients with diffuse tumors and an exon 9 deletion in one patient with a mixed carcinoma; both exons encode putative calcium binding domains. These alterations were not seen in nontumorous gastric tissues. Splice site mutations responsible for the exon deletions were identified in six of these patients, eliminating the possibility of alternative splicing mechanisms. Five of these splice site alterations were confirmed as somatic mutations. Non-splice site mutations were observed in three diffuse type tumors, namely a 69-base pair deletion of exon 10 and two point mutations, one of which destroys a putative calcium binding region. Immunohistochemical evaluation showed E-cadherin immunoreactivity in tumors and lymph node metastases of patients expressing abnormal mRNA. The allelic status of the E-cadherin gene was analyzed in one patient, revealing loss of heterozygosity with retention of a mutated E-cadherin allele. Overall, E-cadherin mutations were identified in 50% (13 of 26) of the diffuse type and in 14% (1 of 7) of the mixed carcinomas. In contrast, two silent E-cadherin mutations (not changing the amino acid sequence) were detected in two tumors of the intestinal type. Our study provides strong in vivo evidence that E-cadherin gene mutations may contribute to the development of diffusely growing gastric carcinomas and support a tumor/metastasis suppressor gene hypothesis.


Subject(s)
Cadherins/genetics , Mutation , Stomach Neoplasms/genetics , Base Sequence , Chromosome Deletion , Humans , Lymphatic Metastasis , Molecular Sequence Data , Polymerase Chain Reaction , RNA, Messenger/analysis
14.
Ophthalmologica ; 208(5): 262-6, 1994.
Article in English | MEDLINE | ID: mdl-7816419

ABSTRACT

Before introducing new antibiotics for corneal organ culture solutions, information about the endothelial cell toxicity is necessary. Therefore, we preserved 132 pig corneas in minimum essential medium with 2% fetal calf serum and 5% dextran T 500 and added 50, 100, 250 and 500 micrograms/cm3 cefmenoxime. Slight endothelial cell damage occurred at a concentration of 100 micrograms/cm3. Damage to endothelial cells was demonstrated by the inhibited uptake of fluorescein diacetate and by other staining procedures. 30% of the substance remained stable during a 10-day culture period as demonstrated by an HPLC method.


Subject(s)
Cefmenoxime/toxicity , Endothelium, Corneal/drug effects , Animals , Biological Transport/drug effects , Cell Survival , Cornea , Culture Media , Dose-Response Relationship, Drug , Endothelium, Corneal/metabolism , Endothelium, Corneal/pathology , Fluoresceins/metabolism , Necrosis , Organ Culture Techniques , Organ Preservation , Swine
15.
Cancer Res ; 53(23): 5797-801, 1993 Dec 01.
Article in English | MEDLINE | ID: mdl-8242638

ABSTRACT

Archival specimens of 25 pulmonary carcinoids including 15 cases of typical carcinoid, 9 atypical carcinoids, and 1 large-cell neuroendocrine carcinoma were analyzed for mutations in exons 5 to 8 of the p53 gene. Mutations were identified in 4 tumors, including 3 out of 15 (20%) typical carcinoids and the single large-cell neuroendocrine carcinoma, but none of the atypical carcinomas showed a mutation. The mutations were acquired during tumor development since they were not present in the corresponding nontumorous tissue. All mutations in the typical carcinoids, a tumor type without epidemiological link to cigarette smoking, were G to A transitions. The level of p53 protein was investigated by immunohistochemistry with the polyclonal antibody CM-1. None of the pulmonary carcinoids investigated showed a positive reaction, despite the presence of missense mutations in two cases. Negative staining of carcinoids with mutations was also observed with the monoclonal antibodies pAb1801 and DO-1. Our data suggest that point mutations of the p53 gene are infrequent in pulmonary carcinoids thus contrasting the findings in other histological types of lung cancer, in particular small-cell lung cancer. Moreover, negative immunostaining for p53 is no indicator for the absence of p53 missense mutations in typical carcinoids.


Subject(s)
Carcinoid Tumor/genetics , Genes, p53 , Lung Neoplasms/genetics , Point Mutation , Adult , Aged , Base Sequence , Carcinoma, Small Cell/genetics , Female , Humans , Immunohistochemistry , Male , Middle Aged , Molecular Sequence Data , Tumor Suppressor Protein p53/analysis
17.
Am J Pathol ; 142(3): 907-15, 1993 Mar.
Article in English | MEDLINE | ID: mdl-8384408

ABSTRACT

The spectrum of p53 gene mutations was determined in formalin-fixed, paraffin-embedded samples of small-cell lung cancer derived from 28 patients. By direct sequencing of exons 5, 7, and 8, including their flanking intron sequences, 18 mutations were identified in 17 tumors (61%), and in all but two of these the wild type allele was lost. In 8 cases, the mutation detected in the tumor was absent from the corresponding normal tissue, indicating that these mutations were somatically acquired. In two patients, identical mutations were found in the primary tumor and corresponding metastases. In a further case, an intrapulmonary metastasis did not show the mutation detected in the primary tumor. The local distribution of the mutations resembled that reported in non-small cell lung cancer and gave no indication of distinct bot spot regions. G-to-T transversions were the predominant type of mutation, reflecting a possible genotoxic influence of carcinogens contained in tobacco smoke. Mutations were equally distributed among tumors with intermediate and oat cell histology and did not show a significant association to age and gender of the patients. Also, no significant relationship was observed between the presence of a mutation and tumor stage (T, N, M) or survival. However, transitions at CpG dinucleotides were restricted to tumors without detectable metastases at the time of biopsy, whereas all other mutations occurred in metastasizing small cell lung cancer.


Subject(s)
Carcinoma, Small Cell/genetics , Genes , Lung Neoplasms/genetics , Point Mutation , Tumor Suppressor Protein p53/genetics , Base Sequence , Carcinoma, Small Cell/pathology , Carcinoma, Small Cell/secondary , Humans , Lung Neoplasms/pathology , Molecular Probes/genetics , Molecular Sequence Data
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