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S Handt

Publications and source records attributed to S Handt.

At least 19 recordsLinked to original sources
PubMed2002

[Criteria of dignity in ultrasound mammography using a 10-MHz-transducer, also with regard to tumor size].

AIM: Ongoing technical progress has increased the accuracy of imaging in ultrasound mammography. Using a 10-MHz-transducer, eight different criteria of dignity were evaluated for validity, also with regard to the size of a tumor. MATERIALS AND METHODS: Over a period of three years, 446 breast tumors were ultrasonographically examined by two experienced medical doctors. The study comprised only suspicious lesions detected by mammography and/or manual palpation. Diagnostic validity was quantified by means of sensitivity, specificity, positive and negative predictive value, as well as the ODDS-ratio. RESULTS: Ultrasound mammography demonstrated a sensitivity of 94.0 %, specificity of 91.4 %, positive predictive value of 95.9 %, and a negative predictive value of 99.1 %. Eight different sonographic criteria were validated separately. The most important signs of malignancy were (in descending order): a highly echogenic halo, spikes, jagged contour, posterior acoustic shadowing, and discontinuity of tissue structure. Features of benign disease were: smooth edge, posterior acoustic enhancement, displacement margin, bilateral acoustic shadowing and continuity of tissue structure. Furthermore, it appeared that the size of a tumor only had consequences on posterior shadowing (p = 0.017). All other features did not show significant variation in relation to tumor size. CONCLUSION: We were able to prove that ultrasound mammography is an excellent medium for the differentiation of benign and malignant breast lesions, when precise indication criteria were adhered to, even in cases of small tumor size.

Adolescent↗
PubMed2001

Percutaneous retrieval of the Tulip vena cava filter: feasibility, short- and long-term changes--an experimental study in dogs.

PURPOSE: To evaluate experimentally the retrievability of the Tulip inferior vena cava (IVC) filter in an in vivo study. Changes which accompany venous healing after filter retrieval were investigated. METHODS: In 12 dogs, 23 filters were inserted percutaneously into the lumbar and intrahepatic segments of the IVC. Two weeks (n = 21 filters) or 3 weeks (n = 2 filters) after insertion, filter retrieval was attempted through an 11 Fr coaxial retrieval sheath system placed via the jugular vein. Follow-up studies before and after filter retrieval included cavography, computed tomography and intravascular ultrasound of the IVC. Seven dogs were killed immediately after filter retrieval to confirm short-term changes of the IVC, and 5 dogs were killed 6 months after filter retraction to evaluate long-term changes of the IVC related to filter retrieval. Post-mortem examinations and histologic specimens of the IVC were obtained to evaluate caval wall abnormalities secondary to filter removal. RESULTS: All but one filter were successfully retrieved 2 weeks post-implantation. However, 3 weeks after insertion, filter retrieval was impossible. There were no complications caused by filter extraction. Follow-up studies after filter retrieval revealed no significant changes in the integrity, morphology or composition of the IVC and pericaval tissue. Histologic examination 6 months after filter retrieval revealed only flimsy fibrotic intimal plaques at the sites of former hook insertion. CONCLUSION: The Tulip filter allows percutaneous insertion and retrieval up to 14 days after insertion, suggesting that it may be useful for either permanent or temporary prophylaxis against pulmonary embolism.

Animals↗
PubMed2001

[Direct evidence of cytomegalovirus in coronary atheromas of patients with advance coronary heart artery disease].

BACKGROUND AND AIM: Experimental and clinical data support an infectious cause of atherosclerosis and thereby coronary artery disease. This study was intended to assess the prevalence and possible clinical associations of the presence of cytomegalovirus DNA within coronary samples from patients undergoing coronary artery bypass grafting. PATIENTS AND METHODS: A coronary thrombendatherectomy was performed in 53 patients with advanced coronary artery disease. Two samples of each atheroma were used for further analysis and pathogen detection. RESULT: In 30% of patients with advanced coronary artery disease cytomegalovirus DNA was detected in coronary samples as assessed by highly sensitive PCR methods. The occurrence of the virus within the vessels was characterized by an inhomogeneous distribution pattern. CONCLUSION: Due to an increased proportion of restenotic lesions and a higher degree of calcification in cytomegalovirus-positive lesions, a causative association between the virus presence and mechanisms of restenosis post angioplasty is further supported. Antiviral pharmacological interventions to prevent restenosis in high-risk patients, however, seem not to be justified by the data currently available.

Aged↗
PubMed2001

Differences in genetic alterations between primary lobular and ductal breast cancers detected by comparative genomic hybridization.

Infiltrating ductal (DC) and lobular carcinoma (LC) of the breast represent the most frequently observed varieties of invasive breast cancer, characterized by differences in their histological and clinical properties. Although comparative genomic hybridization (CGH) of invasive breast carcinomas has revealed a complex and consistent pattern of DNA copy number changes, the data with regard to type specific aberrations are limited. A comprehensive study was therefore performed on 19 LCs and 29 DCs to ascertain type-specific differences of unbalanced DNA copy number changes by CGH. Statistical analysis revealed significantly higher frequencies for underrepresentation of chromosomes 16q (p<0.01), 22 (p<0.05), and 17q (p<0.05), and a lower frequency for overrepresentation of chromosome 8q (p<0.01) in LC. Similar frequencies of non-random chromosomal changes in LC and DC were obtained for gain of 1q (74%/59%) and loss of 19p (53%/52%), parts of 1p (42%/41%) and 11q (21%/24%). Less frequently, gains mainly involving parts of chromosomes 20q, 20p, 3q, and 5p and partial losses of chromosomes 17p and 13 were observed in both groups of tumours. Minimal regions of overlapping amplifications were mapped to 17q23 exclusively in DC (17%) and 11q13-q14 in both DC and LC (21% and 11%, respectively). High occurrences of DNA copy number decreases were detected at the distal part of chromosomes 1p, 19 and 22, but further analysis is required to confirm these imbalances. It is suggested that the observed differences are involved in the development of type-specific properties of DC and LC.

Adult↗
PubMed2001

Trisomy 8 as sole karyotypic aberration in an ovarian metastasizing Sertoli-Leydig cell tumor.

Sertoli-Leydig cell tumors (SLCTs) represent a rare group of sex-cord stromal tumors of the ovary of unknown pathogenesis. We report a SLCT of intermediate differentiation with peritoneal recurrence and lymph node metastasis 12 months after removal, including cytogenetic analysis by comparative genomic hybridization and fluorescence in situ hybridization, which showed trisomy 8 as sole unbalanced karyotypic aberration. Our results provide evidence that a simple numeric chromosomal abnormality in SLCT may be associated with a malignant phenotype and suggest that the molecular pathogenesis of SLCT may be different from ovarian granulosa-stromal cell tumors.

Adolescent↗
PubMed2001

Infectious agents in coronary lesions obtained by endatherectomy: pattern of distribution, coinfection, and clinical findings.

BACKGROUND: Cytomegalovirus (CMV), Chlamydia pneumoniae (C. pneumoniae), and Helicobacter pylori (H. pylori) have been implicated in atherosclerosis and restenosis after angioplasty. The patterns of distribution within coronary lesions and possible coinfections of these pathogens in the coronary vasculature had not previously been evaluated. DESIGN: A prospective, observational clinical study. METHODS: Large coronary specimens (9-105 mm long) were obtained by endatherectomy of 53 patients undergoing aortocoronary bypass surgery. Samples were taken from two different sites of every lesion, resulting in a total of 106 probes. Presence of each pathogen was determined by polymerase chain reaction, subsequent hybridization, and DNA sequencing. RESULTS: Cytomegalovirus and C. pneumoniae were detected in 30 and 32% of the samples, respectively; H. pylori was not detectable. The pathogens were not homogeneously distributed. A concurrent infection with both pathogens was observed in five of 106 (5%) lesions and five of 53 (9%) patients. Restenotic lesions were more often found in specimens in which cytomegalovirus was detected (five of 16 versus two of 37). Patients with C. pneumoniae-positive coronary lesions more commonly presented with unstable angina. CONCLUSIONS: Inhomogeneous infections with cytomegalovirus and C. pneumoniae of coronary atherosclerotic lesions are found to be prevalent when serial analysis is performed. Concurrent infection with both pathogens occurs coincidentally; however, possible clinical implications of this new observation and the pathogenic impact on atherosclerosis need further investigation.

Aged↗
PubMed2000

Simultaneous appearance of an adenomyoma and pancreatic heterotopia of the stomach.

Adenomyomas of the stomach are rare tumours characterised by duct/gland-like structures embedded within a smooth muscle stroma. Although the histogenesis of adenomyomas remains unclear, the histological appearance has justified the assumption that these are abortive forms of pancreatic heterotopia. We report an unusual case with simultaneous and independent appearance of both adenomyoma and pancreatic heterotopia of the stomach including immunohistochemical characterisation, supporting the concept of a common histiogenetic origin of both lesions.

Adenomyoma↗
PubMed2000

Benign metastasizing leiomyoma: a cytogenetically balanced but clonal disease.

Benign metastasizing leiomyoma (BML) is a rare condition, characterized by the occurrence of multiple smooth-muscle nodules, most often located in the lung after previous hysterectomy because of histologically benign appearing leiomyoma. Although the condition resembles a metastatic process, case studies provided evidence that it may be the result of an intravenous leiomyomatosis or an independent and multifocal smooth-muscle proliferation. Comparative genomic hybridization and X-chromosome inactivation analysis were used in a case of BML to determine whether pulmonary and uterine tumors are related one to another. A balanced karyotype, previously reported in leiomyomas and an identical X-chromosome inactivation pattern found in all tumorlets, is most consistent with a monoclonal origin of both uterine and pulmonary tumors and the interpretation that pulmonary lesions are metastatic.

Adult↗
PubMed2000

Interphase cytogenetics of multicentric renal cell tumours confirm associations of specific aberrations with defined cytomorphologies.

To demonstrate associations of certain chromosomal aberrations with defined renal cell tumour (RCT) subtypes, we analysed 239 tumour nephrectomy cases for specimens with multicentric tumours. Chromosomal in situ hybridization was then performed on 15 cases with 34 foci (16 conventional renal cell carcinomas (RCCs), and 18 papillary RCTs (11 carcinomas and seven adenomas) for specific chromosomal aberrations, using alpha-satellite probes for chromosomes 3, 7 or 17. Particular preference was given to cases which had separate foci with different cytomorphologies. Furthermore, we compared aberrations in relation to tumour size, stage, grade and between different foci in a specimen. Thirty-four cases had multiple tumours. Forty-seven per cent of the multicentric tumours were conventional RCCs and 53% papillary RCTs (against 83% solitary conventional RCCs and 5% solitary papillary RCTs). Three conventional RCCs sized 8 mm (G3), 13 cm (pT2, G2) and 15 cm (pT3b, G3), respectively, revealed monosomy 3, and 13 were disomic. Seventeen papillary RCTs (11 carcinomas and six adenomas) displayed trisomy 17, irrespective of size or grade. Four papillary carcinomas and six papillary adenomas had trisomy 7, and the rest (seven papillary carcinomas and one papillary adenoma) revealed disomy 7. In conclusion, papillary RCTs were tendentially multicentric. Although specific for conventional RCCs heedless of size, monosomy 3 was only observed in high-grade and/or advanced tumours. Trisomy 17 was only detectable in papillary RCTs irrespective of tumour state, showing increased copies with tumour growth. Papillary RCTs also appeared to lose some copies of chromosome 7 with tumour progress, possibly reflecting malignancy.

Carcinoma, Papillary↗
PubMed2000

Evaluation of in vivo biocompatibility of different devices for interventional closure of the patent ductus arteriosus in an animal model.

OBJECTIVE: To evaluate the in vivo biocompatibility of three different devices following interventional closure of a patent ductus arteriosus (PDA) in an animal model. MATERIALS AND METHODS: A medical grade stainless steel coil (n = 8), a nickel/titanium coil (n = 10), and a polyvinylalcohol foam plug knitted on a titanium wire frame (n = 11) were used for interventional closure of PDA in a neonatal lamb model. The PDA had been maintained by repetitive angioplasty. Between one and 278 days after implantation the animals were killed and the ductal block removed. In addition to standard histology and scanning electron microscopy, immunohistochemical staining for biocompatibility screening was also undertaken. RESULTS: Electron microscopy revealed the growth of a cellular layer in a cobblestone pattern on the implant surfaces with blood contact, which was completed as early as five weeks after implantation of all devices. Immunohistochemical staining of these superficial cells showed an endothelial cell phenotype. After initial thrombus formation causing occlusion of the PDA after implantation there was ingrowth of fibromuscular cells resembling smooth muscle cells. Transformation of thrombotic material was completed within six weeks in the polyvinylalcohol plug and around the nickel/titanium coil, and within six months after implantation of the stainless steel coil. An implant related foreign body reaction was seen in only one of the stainless steel coil specimens and in two of the nickel/titanium coil specimens. CONCLUSION: After implantation, organisation of thrombotic material with ingrowth of fibromuscular cells was demonstrated in a material dependent time pattern. The time it took for endothelium to cover the implants was independent of the type of implant. Little or no inflammatory reaction of the surrounding tissue was seen nine months after implantation.

Animals↗
PubMed2000

Expression of heat shock proteins 72/73 in human peritoneal mesothelial cells in vivo and in vitro.

Leukocyte accumulation during peritonitis leads to an injurious microenvironment which is involved in the host defense reaction but is also thought to cause peritoneal damage. We tested the hypothesis that mesothelial cells (MC) respond to the injurious microenvironment during peritonitis by an increased expression of heat shock proteins (HSP 72/73), a basic way by which cells are protected against injury. Comparison of resting MC and activated MC during peritonitis in vivo by means of immunohistochemistry revealed an increased expression of HSP 72/73. As assessed by Western immunoblotting, incubation of MC in vitro with tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) caused a time-dependent induction of HSP 72/73 expression, which was maximal 6 h after stimulation. We suggest that the increased HSP 72/73 expression of MC during peritonitis is in part induced by TNF-alpha and IL-1beta and may exert a cell-protective function, lessening MC damage during peritonitis.

Base Sequence↗
PubMed2000

[Ovarian mucinous adenocarcinoma, mucocele of the appendix and pseudomyxoma peritonei: case report with immunohistochemical analysis].

Women with pseudomyxoma peritonei may have both, appendiceal and ovarian mucinous tumors, and there is a considerable debate regarding the site of origin of the tumor in such cases. Recent studies which have investigated the histological and immunohistochemical profile of these tumors showed, that ovarian tumors in most cases are secondary to the appendiceal tumors. In our case report we demonstrate that, despite of extensive immunohistochemical examinations (analysis of CK 7, 18, 20, CEA, HAM 56), it may be difficult to determine the histogenetic origin of pseudomyxoma peritonei.

Adenocarcinoma, Mucinous↗
PubMed1999

Expression of glypican-4 in haematopoietic-progenitor and bone-marrow-stromal cells.

Heparan sulphate proteoglycans and the extracellular matrix of bone-marrow-stromal cells are important components of the microenvironment of haematopoietic tissues and are involved in the interaction of haematopoietic stem and stromal cells. Previous studies have emphasized the role of heparan sulphate proteoglycan synthesis by bone-marrow-stromal cells. In the present study we describe the expression of glypican-4 (GPC-4), belonging to the glypican family, in bone-marrow-stromal cells and haematopoietic-progenitor cells of human and murine origin. Expression of GPC-4 was shown on the mRNA-level by reverse transcription-PCR and Northern blot analysis. Amplification products were cloned and sequenced, to confirm these results. To analyze the expression of GPC-4 on the protein level, polyclonal antibodies against selected peptides were raised in rabbits. Western blot analysis showed expression of GPC-4 as a heparan sulphate proteoglycan in the human haematopoietic-progenitor cell line TF-1 and normal human bone marrow. These results were confirmed by FACS analysis of TF-1 cells. Furthermore, GPC-4-positive progenitor cells and stromal cells were enriched from normal human bone marrow by magnetic-cell sorting and analysed by confocal laser-scanning microscopy.

Amino Acid Sequence↗
PubMed1999

[Radioprotection of human endothelial cells by sodium selenite].

BACKGROUND: Sodium selenite is applied in tumor patients during chemo- or radiotherapy due to its cytoprotective effects. Aim of our study was to evaluate the effect of exposure with sodium selenite on proliferation of human endothelial and tumor cells after irradiation. MATERIALS AND METHODS: We studied the proliferative activity of human umbilical vein endothelial cells in comparison to tumor cells of the HeLa, MIA Paca-2 and SiHa cell line after single-dose irradiation with 2 or 10 Gy and controls without irradiation. All cells had been exposed to different concentrations of sodium selenite prior to irradiation. Evaluation was done by BrdU-ELISA. RESULTS: Exposure of human endothelial cells with sodium selenite concentrations > or = 100 micrograms/l led to an increase of BrdU proliferation index. This effect was markedly weaker in HeLa cells and not found in SiHa and MIA Paca-2. CONCLUSIONS: High concentrations of sodium selenite can counteract the decrease of proliferative activity caused by irradiation in human endothelial cells and thus exert a radioprotective effect on these cells. This effect was observed by far stronger in endothelial cells than in tumor cells, implying the possible clinical use of sodium selenite as a protective agent for normal tissue in radiotherapy.

Cell Division↗
PubMed1999

Expression and function of beta(1) and beta(3) integrins of human mesothelial cells in vitro.

Mesothelial cells (MC) and extracellular matrix (ECM) components are thought to play a pivotal regulatory role during the inflammatory-reparative response of serosal membranes. Integrins are known to serve as cellular ECM receptors, but mesothelial integrin expression and its function, particularly its role for attachment to different ECM components, remain to be elucidated. The aim of the present study was to characterize the integrin expression of human omentum majus derived MC (HOMC) in vitro by immunohistochemistry and to investigate their functional significance with regard to HOMC adhesion to fibronectin (fn), vitronectin (vn), collagen IV (coll IV), and laminin (ln). Mesothelial cells in vitro strongly expressed beta(1), beta(3), alpha(2), alpha(3), alpha(5), and alpha(v) chains. A weak reactivity was found for alpha(1) and alpha(6), but no alpha(4) reactivity was detectable. Compared to the control, fn, vn, coll IV, and ln caused a significant 2.6-, 2.2-, 2-, and 1.6-fold increase of HOMC adhesion, respectively. Inhibition studies revealed that HOMC attachment to fn is mediated by alpha(5)beta(1), alpha(v)beta(1), and alpha(v)beta(3), with a synergistic effect of alpha(5)beta(1) and alpha(v)beta(3). Adhesion to vn is mediated by alpha(v)beta(1) and alpha(v)beta(3). Integrins alpha(1)beta(1), alpha(2)beta(1), and alpha(3)beta(1) mediate adhesion to coll IV and ln. We suggest that the integrin expression and function of mesothelial cells described here play an important role in the interaction of MC with the ECM, particularly during the acute and chronic inflammatory-reparative response of serosal membranes.

Antigens, CD↗
PubMed1999

[Radical perineal prostatectomy without lymphadenectomy. Patients with cT1 + 2, G1 +2, PSA < or = 10 ng/ml prostate carcinoma].

Pelvic lymphadenectomy in patients with organ confined prostate cancer (PCa) is of no therapeutic value and is questionable in many patients because of the low incidence of metastases. 49 patients with < or = cT2 b, G1 + 2, PSA < or = 10 ng/ml underwent laparocopic pelvine lymphadenectomy and radical perineal prostatectomy. Only 1 patient (2%) had microscopic metastases which were missed on frozen section. Because of these own results and those reported in the literature we then performed in patients with this constellation the radical perineal prostatectomy without lymphadenectomy (n = 32). The differences present in both groups concerning complication rate and morbidity are due to laparoscopic lymphadenectomy and the learning curve in perineal prostatectomy.

Aged↗
PubMed1999

The role of soluble adhesion molecules in evaluating endothelial cell activation in preeclampsia.

OBJECTIVE: Adhesion molecules, such as vascular cell adhesion molecule 1, are known to be increased in the serum of patients with preeclampsia, indicating that these molecules are possible markers of endothelial cell activation. We investigated the influence of serum from women with preeclampsia on the expression of adhesion molecules by cultured endothelial cells. STUDY DESIGN: Human umbilical vein endothelial cells were cultured in Ham/Iscove modified Dulbecco's medium containing 20% pooled human serum, l -glutamine (200 mmol/L), penicillin, and streptomycin. We stimulated these cells for 24 hours with sera from patients with preeclampsia and then determined the levels of vascular cell adhesion molecule 1, intercellular cell adhesion molecule 1, E-selectin, and P-selectin in the supernatant and in the maternal serum by means of enzyme-linked immunosorbent assay. These results were compared with those of sera obtained from normotensive pregnant and nonpregnant women. In addition, the expressions of these adhesion molecules on the endothelial surface were determined by immunofluo-rescence microscopy. RESULTS: Only for vascular cell adhesion molecule 1 and E-selectin were elevated plasma levels found in hypertensive patients, whereas intercellular cell adhesion molecule 1 and P-selectin showed similar plasma levels in all the patients. No differences in the levels of the adhesion molecules were found between the supernatants of endothelial cell cultures after stimulation with sera from patients with preeclampsia and those after stimulation with normotensive control sera. In contrast, with immunofluorescence microscopy we could detect higher amounts of vascular cell adhesion molecule 1, intercellular cell adhesion molecule 1, and E-selectin on the endothelial surface after stimulation with sera from women with preeclampsia. CONCLUSION: Although vascular cell adhesion molecule 1 and E-selectin were elevated in maternal serum samples from women with preeclampsia and on the endothelial surface after stimulation with such sera, there were no detectable increases in the levels of both of these adhesion molecules in the supernatant of cultured endothelial cells. We therefore assume that sera from women with preeclampsia may cause endothelial cell activation. Because we could not detect elevated concentrations of any of the investigated adhesion molecules in the supernatant of endothelial cells, we believe that factors other than sera from women with preeclampsia seem to play a major role in the release of soluble forms of adhesion molecules from the endothelial membrane.

Adult↗