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Biomedical subjects

T Mattfeldt

Publications and source records attributed to T Mattfeldt.

At least 37 records · Page 2Linked to original sources
PubMed1999

Total, subtotal, and partial surgical removal of cervicofacial lymphangiomas.

OBJECTIVES: To compare different surgical interventions for the treatment of extensive cervicofacial lymphangiomas and to define the minimal extent of surgery necessary to control disease. DESIGN: Retrospective study. Mean +/- SD follow-up was 31+/-4 months after surgery. Surgical procedures were grouped as follows: (1) total removal, (2) subtotal removal (all cystic structures removed, small plaques of cyst walls left attached to vital structures), (3) partial removal (major cysts removed, some partially resected cystic structures left in place), and (4) incision and aspiration with subsequent compression bandage. Control of disease was defined as no recurrent or residual tumor or as recurrent or residual tumor less than 10% of initial tumor size without evidence of growth on several postoperative examinations and without clinical symptoms or aesthetic disfigurement. PATIENTS: Twenty-one patients with cervicofacial lymphangiomas (>3 cm in maximum diameter) without thoracic involvement were evaluated. Fifteen patients were 6 years or younger and 6 were older than 6 years. No surgery was yet performed in 3 patients, for a total of 24 surgical interventions in 18 patients. SETTING: Hospitalized care in 2 referral centers. RESULTS: After total removal, disease was controlled in 5 of 5 cases; after subtotal removal, in 8 of 9 cases; after partial removal, in 1 of 7 cases; and after incision and aspiration with subsequent compression bandage, in 0 of 3 cases. Two complications were encountered-1 fully reversible paresis of the marginal branch of the facial nerve and 1 secondary healing. CONCLUSIONS: Surgical removal of cervicofacial lymphangiomas is a safe treatment modality. Disease control can be achieved if all cystic structures are removed. Small plaques of cyst walls attached to vital structures may be left in place. If small cystic extensions of lymphangiomas are only opened and left in place or if lymphangiomas are only drained following compression bandage, symptomatic residual tumor or recurrence is frequent.

Child↗
PubMed1999

Tumor of the ampulla of Vater: experience with local or radical resection in 171 consecutively treated patients.

HYPOTHESIS: This study was designed to evaluate prospectively oncological factors determining survival after resection of tumors of the papilla, comparing local and radical oncological resection. We hypothesized that, in malignant lesions of the ampulla, the T and N stages are major determinants of the patient's long-term outcome. BACKGROUND DATA: The frequency of malignant lesions in adenomas of the papilla is about 26%. Villous adenoma of the ampulla is considered a premalignant lesion. Local excision has been recommended for benign adenoma and pancreatoduodenectomy for malignant lesions. PATIENTS AND METHODS: From January 1, 1982, through June 30, 1997, 171 patients with tumors of the ampulla of Vater were surgically treated. Demographics, intraoperative factors, tumor pathological findings, and postoperative short- and long-term follow-up data were documented prospectively. Of the patients, 45 had adenoma of the papilla and 126 had malignant lesions of the ampulla. RESULTS: Local resection was performed in 40 of the 45 patients with adenoma. In 98 of the 126 patients with malignant lesions, a radical Kausch-Whipple resection or pylorus-preserving pancreatoduodenectomy was used. Of the patients with benign adenoma, 40 had local resection and 5 had pylorus-preserving pancreatic head resection, with a hospital mortality of 0%. Thirty of 35 patients had villous adenoma, 9 (30%) of the 30 with severe dysplasia. Of the 126 patients with malignant lesions, 98 had partial pancreatoduodenectomy and 10 had ampullectomy, with an overall hospital mortality of 3.1% for patients who underwent resection. Seventy-eight of the 98 patients had an R0 resection. The 5-year survival probability for all patients who underwent resection was 84% for cancer stage I, 70% for stage II, and 27% for stage III. In 8 patients with villous adenoma and carcinoma in situ and in 10 patients with cancer in the adenoma, ampullectomy with local lymph node dissection was performed. In 4 of the patients who had villous adenoma and a carcinoma in stage pT1 N0, an R0 resection was performed, resulting in cure of cancer. On the basis of a multivariate regression analysis, the prognosis after oncological resection of cancer of the ampulla is determined by the absence of lymph node metastasis (P<.05), the absence of infiltration into the pancreatic head tissue (P<.05), and the application of an R0 resection. CONCLUSIONS: In patients with villous adenoma of the ampulla, ampullectomy was an adequate surgical treatment. In patients with a low-risk cancer in stages pTis and pT1 N0 M0, G1 or G2, a local resection with ampullectomy including local lymph node dissection is justified. An oncological resection of cancer of the ampulla by means of a pylorus-preserving partial pancreatoduodenectomy or the Kausch-Whipple resection is the surgical procedure of choice; the 3- and 5-year survival rates were 72% and 52%, respectively, in patients with R0 resections.

Adenoma↗
PubMed1999

Intraductal papillary mucinous tumor of the pancreas.

BACKGROUND: Since 1996 the classification of pancreatic tumors was replaced by the new World Health Organization nomenclature. Formerly mucinous cystadenomas are now distinguished between intraductal papillary mucinous tumors of the pancreas (IPMT) and mucinous cystadenomas. METHODS: We reevaluated the pathological specimen and surgical therapy of 23 consecutive patients and followed up these patients up for 4 years in median. Between 1987 and 1997 we treated 8 patients with IPMT and 15 patients with mucinous cystadenomas. RESULTS: Eighty-five per cent of all patients were symptomatic. Ultrasonography and computed tomography were the most sensitive diagnostic techniques. In 25%, the entire pancreas was involved with IPMT; that was not the case in any of the patients with mucinous cystadenoma. All patients were resected with no perioperative mortality. After dismissal from the hospital, all resected patients are still alive after a median follow-up of 4 years. In no patient with IPMT, but in 1 patient with mucinous cystadenoma, the tumor recurred. CONCLUSION: Surgical resection is the treatment of choice in all cystic tumors, and the late outcome of IPMT is as good as for mucinous cystadenoma.

Cystadenoma, Mucinous↗
PubMed1999

Prediction of prostatic cancer progression after radical prostatectomy using artificial neural networks: a feasibility study.

OBJECTIVE: To report a methodological feasibility study in a small series of patients with node-negative organ-confined prostatic cancer, using artificial neural networks to predict tumour progression after radical prostatectomy and thus help to identify high-risk patients who would benefit from adjuvant treatment. PATIENTS AND METHODS: A group of 20 patients with pT2N0 prostatic cancer and postoperative tumour progression was compared with a control group of 20 patients with no progression, matched for age, duration of follow-up and preoperative serum prostate-specific antigen level. Histopathological data were obtained from the radical prostatectomy specimens, i.e. the Gleason score, World Health Organisation (WHO) grade and maximum diameter of the tumour transects. The volume and surface area of the epithelial tumour component and of the lumina of the neoplastic glands per unit tissue volume were estimated by morphometric methods. To predict recurrence, multilayer feedforward networks with backpropagation (MLFF-BP), two implementations of learning vector quantization (LVQ), and linear discriminant analysis (LDA) were applied. The ability of these models to correctly classify new cases was tested using the 'leave-one-out' technique. RESULTS: Progression was predicted correctly in 85% of newly presented cases from the three routine histopathological variables alone. On the basis of the four morphometric variables alone progression was predicted correctly in 93% of cases. The use of all seven variables as input data only slightly improved the quality of prediction. The best results were obtained by the LVQ networks and LDA, followed by MLFF-BP networks. CONCLUSIONS: In this methodological feasibility study, the progression of pT2N0 prostatic cancer after radical prostatectomy could be predicted with good accuracy, sensitivity and specificity from routine variables or morphometric texture variables using artificial neural networks. These results suggest that this approach should be assessed in a prospective study with more cases.

Biopsy↗
PubMed1999

[Conjunctival pseudolymphoma in infectious mononucleosis].

BACKGROUND: The most frequent manifestation of an infection with Epstein-Barr virus is the mostly unilateral transient follicular conjunctivitis. PATIENT: A 19-year-old man was evaluated for a unilateral salmon colored subconjunctival mass that had developed over one week. Additionally, the patient had painful cervical lymph nodes and a sore throat. Blood tests demonstrated a lymphocytosis and a high titer for Epstein-Barr-Virus-IgG and -IgM which was consistent with infectious mononucleosis. A biopsy form the conjunctival mass showed a mixed cellular infiltrate including lymphocytes, plasma cells, histocytes, and cells with a prominent eosinophilic nucleolus. The lesion displayed a spontaneous regression over the following 8 weeks. CONCLUSION: Infectious mononucleosis should be considered with a conjunctival tumor which may mimic a lymphoma.

Adult↗
PubMed1998

Chromosomal changes during progression of transitional cell carcinoma of the bladder and delineation of the amplified interval on chromosome arm 8q.

The cascade of genetic alterations leading to malignant transformation has been described for adenocarcinoma of the colon but is not established for other common tumor entities. In the present study, different stages of transitional cell carcinoma (TCC) of the bladder are analyzed by comparative genomic hybridization. A dynamic pattern of the chromosomal changes during tumor progression is described. Deletion of chromosome arm 9q is the earliest genetic alteration in pTa tumors. In stage pT1 carcinomas, losses of 9q, 9p, and 11p and gain of 1q and 8q are the most common. In addition to the changes specific for earlier stages, gain of 5p and 20q becomes prominent in carcinomas stage > or =pT2. Association analysis reveals a remarkable cooccurrence of 9p deletion with gain of 5p and 20q in > or =pT2 tumors. In order to determine more precisely the size of the amplified segment and the degree of amplification on chromosome arm 8q in stage pT1 tumors, this region was analyzed by semiquantitative PCR using polymorphic microsatellite markers. These studies revealed an up to 13-fold amplification. The common region of amplification could be narrowed down to 8q22.3 and between GAAT1A4 and D8S1834 (about 7 cM).

Carcinoma, Transitional Cell↗
PubMed1998

Cystic tumours of the pancreas: diagnostic accuracy, pathologic observations and surgical consequences.

BACKGROUND: Cystic neoplasms of the pancreas account for only 1% of primary pancreatic lesions. However, patients with these tumors are diagnosed more frequently. Up to now, nonsurgical management is still the established form of treatment of benign cystic tumours of the pancreas. METHODS: Between 1987 and 1996 we treated 51 patients with serous and mucinous cystadenoma and their malignant counterparts, serous and mucinous cystadenocarcinoma. RESULTS: Eighty-five percent of the patients presented symptoms. Computed tomography and endoscopic cholangiopancreatography (ERCP) were the most sensitive diagnostic techniques; however, in three patients with serous cystadenoma and in one patient with serous cystadenocarcinoma, ERCP findings were completely normal. The tumour was resected in all but one patient. There was no perioperative mortality. After dismissal from the hospital, all patients in whom benign tumours had been resected are still alive; however, the late mortality of mucinous cystadenocarcinoma was 36% after a median follow-up of 6 years. CONCLUSION: Surgical resection is recommended in all cystic tumours, even in serous cystic tumours, because symptoms may develop and malignant transformation to serous cystadenocarcinoma is possible.

Adult↗
PubMed1998

Modulation of Ca2+-activated K+ channels in human vascular cells by insulin and basic fibroblast growth factor.

Insulin and basic fibroblast growth factor (bFGF) play an important role in the pathogenesis of atherosclerosis and have been shown to have vasodilatory effects. Since modulation of vascular ion channels determines membrane potential and thereby influences essential Ca2+-dependent intracellular pathways, we have investigated the effect of insulin and bFGF on Ca2+-activated K+ channels (BKCa) in human umbilical vein endothelial cells (HUVEC) and smooth muscle cells. The latter were obtained from either atherosclerotic plaques (SMCP) or from media segments (SMCM) of human coronary arteries. Using the patch-clamp technique, insulin (100 microU/ml) caused a significant increase in BKCa open-state probability in SMCP and HUVEC, whereas no significant changes were observed in SMCM. Basic FGF (30 ng/ml) revealed a significant increase in BKCa activity in HUVEC and a significant decrease in the BKCa open-state probability in SMCP, but caused no changes in SMCM. Thus, growth factors modulate vascular BKCa in a cell-type specific manner, which may be of importance concerning vasoactive and atherogenic effects of growth factors.

Arteriosclerosis↗
PubMed1998

Genetic alterations in chronic pancreatitis: evidence for early occurrence of p53 but not K-ras mutations.

BACKGROUND: In patients suffering from chronic pancreatitis the risk for the development of pancreatic cancer ranges from 4 to 6 per cent. Various mutations are associated with pancreatic cancer, especially of p53 and K-ras. The incidence of these mutations in resected chronic pancreatitic tissue was investigated. METHODS: In the present study DNA from 80 samples of tissue from patients with chronic pancreatitis was isolated and subjected to single-strand conformation polymorphism (SSCP) analysis of p53 exons 5-9 and restriction fragment length polymorphism analysis of K-ras (codon 12). RESULTS: No mutations in the K-ras gene were detected. On SSCP analysis, eight of 80 cases of chronic pancreatitis showed alterations (two in exon 5, four in exon 6, two in exon 7). DNA sequence analysis revealed one deletion of 21 amino acids (exon 5), four polymorphisms in exon 6 with no change in the amino acid sequence, one point mutation in exon 5, and two point mutations located in the intron between exons 6 and 7. CONCLUSION: These data show that in some cases of chronic pancreatitis mutations in the p53 gene occur without morphological evidence of pancreatic cancer.

Chronic Disease↗
PubMed1998

Expression of intercellular adhesion molecule-1 in human coronary endothelial and smooth muscle cells after stimulation with tumor necrosis factor-alpha.

BACKGROUND: The intercellular adhesion molecule-1 (ICAM-1) is one of several human cell adhesion molecules that play a critical role in the early stages of postangioplasty restenosis. In this study, the in-vitro expression of ICAM-1 in human coronary endothelial cells and human coronary smooth muscle cells (SMC) after stimulation with tumor necrosis factor-alpha (TNF-alpha) was investigated. METHODS AND RESULTS: SMC were isolated from the media of normal human coronary arteries (n = 26) up to 10 h post mortem (HCMSMC) and from human atherosclerotic coronary arteries (HCPSMC) that were extracted by thrombendarterectomy (n = 25). Endothelial cells of human coronary arteries (HCAEC) were purchased from Clonetics (Cell System, Remagen, Germany), and endothelial cells from human umbilical cord veins (HUVEC) were isolated after vaginal delivery. For investigations of the effect of TNF-alpha (2.5, 5, 10, and 20 ng/ml) on the proliferative activity of HUVEC, HCAEC, HCPSMC, and HCMSMC, serum-free media was used. After 24 h cell number and cell size distribution were measured in a cell analyzer system. The proliferation of HCPSMC and HCMSMC was increased by TNF-alpha; however, significant differences compared with controls were not reached. The proliferation of HUVEC and HCAEC was significantly reduced by TNF-alpha. For investigations of the effect of TNF-alpha (2.5, 5, 10, and 20 ng/ml) on the surface expression of ICAM-1, monoclonal anti-ICAM-1 antibodies (84H10) were used. The expression of ICAM-1 was analyzed using an immunofluorescence microscope. For flow cytometry analysis, 5 x 10(3) cells (100% gated) were analyzed using a fluorescence-activated cell sorter. In control cultures with no stimulation, the expression of ICAM-1 was positive in HCAEC, HCPSMC, HCMSMC, and HUVEC. TNF-alpha stimulated the expression of ICAM-1 in a time- and dose-dependent manner. After maximal stimulation with TNF-alpha (20 ng/ml for 24 h), the expression of ICAM-1 was stronger in HCMSMC than in HCPSMC. CONCLUSIONS: These results suggest that the cytokine TNF-alpha regulates the expression of ICAM-1 in both human coronary endothelial cells and SMC, and could therefore play an important role in the pathophysiology of inflammatory and immune processes in restenosis after angioplasty.

Cell Division↗
PubMed1998

[Cystic neoplasms of the pancreas: surgical therapy and chances for cure].

Between 1986 and 1997 we treated 67 patients with 68 cystic tumors of the pancreas including 17 mucinous cystadenocarcinomas, four serous cystadenocarcinomas, 15 mucinous cystadenomas, 18 serous cystadenomas, ten intraductal papillary-mucinous tumors, three solid-pseudopapillary tumors, and one cystic neuroendocrine tumor. Regarding surgical therapy our results reveal a differentiated management with respect to the histological findings. While in benign tumors a local resection is adequate the cystadenocarcinomas require an extended resection. In general there is an indication for surgical therapy in all cystic tumors of the pancreas--not only in malignant neoplasias. A nonoperative management is not justified. With a mean follow-up of 35 months the prognosis of the patients with a benign cystic tumor was excellent revealing a mortality of 0% whereas survival of the patients with a cystadenocarcinoma was 67% at five years.

Adult↗
PubMed1998

[Radical surgery in cystadenoma of the pancreas--long-term experiences with 35 patients].

We report on 15 patients with mucinous and 19 patients with serous cystadenoma of the pancreas. Cystadenomas were more common in female patients (22/12), and CT was the most sensitive diagnostic tool. There was no mortality in the short or the long term (median 6 years); however, mucinous cystadenomas tend to recur when not treated by radical resection.

Aged↗
PubMed1997

XX-agonadism in a fetus with multiple dysraphic lesions: a new syndrome.

We report on a 19-week-old fetus with a 46,XX karyotype, normal female external genitalia, complete gonadal agenesis, large encephalocele, spina bifida, and omphalocele. We postulate a new syndrome. Hitherto no consistent malformation patterns have been observed in agonadism patients. True agonadism, including even the unusual finding of an XX gonosomal status, is obviously not as rare as suggested.

Abnormalities, Multiple↗
PubMed1997

Ca(2+)-activated K+ channels in human smooth muscle cells of coronary atherosclerotic plaques and coronary media segments.

The behavior of Ca(2+)-activated K+ channels of large conductance (BKCa) in smooth muscle cells, which were obtained from atherosclerotic plaque material (SMCP) and from media segments (SMCM) of human coronary arteries, were compared using the patch-clamp technique. Voltage-clamp protocols in cell-attached patches revealed the characteristic voltage-dependent activation of BKCa in both cell groups. Single-channel conduction as 216.4 +/- 16.7 pS (n = 6) in SMCP and 199.9 +/- 6.7 pS (n = 6) in SMCM in symmetrical 140 mM K+ solutions. Using outside-out patches, external perfusion with 500 microM tetraethylammonium ions caused a typical "flickery block" of the unitary current. The selective BKCa channel inhibitor iberiotoxin (50 nM) effectively blocked BKCa, channel activity. Comparing BKCa open-state probabilities (P0) at +80 mV in cell-attached patches, a highly significant difference between SMCP (P0 = 0.1438 +/- 0.1301; n = 15) and SMCM (P0 = 0.0093 +/- 0.0044; n = 15; Kruskal-Wallis test, p < 0.001) was found. In contrast to this finding, there was no significant difference in the open-state probability of BKCa, between SMCP (P0 = 0.542 +/- 0.0237; n = 9) and SMCM (P0 = 0.0472 +/- 0.0218; n = 10; p = n.s.) using inside-out patches. The results show an interesting difference in the behavior of large conductance Ca(2+)-activated K+ channel in SMCP compared to SMCM with a significantly higher channel activity in human smooth muscle cells obtained from coronary atherosclerotic plaque material. This finding may indicate an important functional role of BKCa channels in the development of atherosclerosis.

Calcium↗
PubMed1997

Nonlinear deterministic analysis of tissue texture: a stereological study on mastopathic and mammary cancer tissue using chaos theory.

Signals from some dynamical systems look like stochastic processes although their latent mechanism is deterministic. When such systems show sensitive dependence on small changes of initial conditions, they are denoted as deterministic chaos. Motivated by recent advances in statistical inference methods for chaotic systems and by the concept of spatial chaos, we present a deterministic approach to the study of epithelial tissue texture. Methods for estimation of the autocorrelation function, for evaluation of the power spectrum, for attractor reconstruction, for estimation of the Lyapunov exponent and of the correlation dimension, and for the generation of surrogate data sets are outlined. In our biological example, these methods are applied to 20 cases of mastopathy as compared to 20 cases of mammary cancer. The input signals for the analysis were estimates of epithelial fraction measured at low magnification within 5100 equally spaced line segments per case perpendicular to an arbitrarily directed axis. The results suggest the existence of a low-dimensional deterministic attractor in mastopathic tissue texture, which is replaced by coloured noise in the majority of mammary carcinomas. Biological mechanisms for this finding and scale effects are discussed, and some methodological aspects and possible extensions of our approach are outlined.

Breast Neoplasms↗
PubMed1997

Laser therapy in dogs and humans--is there a difference?

OBJECTIVE: To compare quantitatively the reduction of volume of benign prostatic hyperplasia (BPH) achieved by laser therapy in dogs and men. PATIENTS, MATERIALS AND METHODS: Twelve mongrels, with a mean prostatic volume of 33.4 mL, underwent transurethral laser treatment using an Nd:YAG laser with an Ultraline fibre at 60 W power setting. The reduction in prostatic volume was assessed quantitatively 3 months after treatment using stereological methods. Forty patients (mean age 70.2 years, range 51-84) with symptomatic BPH (pre-operative mean prostate volume 46.3 mL) were treated under similar operative conditions with the same laser, power and fibre system. Their urinary performance was assessed before and 6 months after treatment using urinary flow rates, residual volume and a symptom score, and their prostatic volume and necrosis assessed using transrectal ultrasonography. RESULTS: After laser treatment, the mean reduction in the dog prostate volume was 50% and in the patients was only 21%. The different impact was probably caused by anatomical differences between the human and dog prostate; the human prostate consists mainly of stromal tissue and the canine prostate of glandular epithelium. CONCLUSIONS: The canine model gives only an approximate guide to the extent of tissue destruction that laser treatment can achieve in men with BPH. Furthermore, tissue differences between men may also affect the response to laser treatment.

Aged↗
PubMed1996

Xp-duplications with and without sex reversal.

Duplications in Xp including the DSS (dosage sensitive sex reversal) region cause male to female sex reversal. We investigated two patients from families with Xp duplications. The first case was one of two sisters with karyotype 46,XY,der(22),t(X;22)(p11.3;p11)mat and unambiguous female genitalia. The living sister was developmentally retarded, and showed multiple dysmorphic features and an acrocallosal syndrome. The second case was a boy with a maternally inherited direct duplication of Xp21.3-pter with the breakpoint close to the DSS locus. He had multiple abnormalities and micropenis, but otherwise unambiguous male genitalia. We performed quantitative Southern blot analysis with probes from Xp22.13 to p21.2 to define the duplicated region. Clinical, cytogenetic, and molecular data from both patients were compared with those of previously reported related cases. A comparison of the extragenital symptoms revealed no differences between patients with or without sex reversal. In both cases, the symptoms were non-specific. Among 22 patients with a duplication in Xp, nine had unambiguous female genitalia and a well-documented duplication of the DSS region. Two patients with duplication of DSS showed ambiguous external genitalia. From these data, we conclude that induction of testicular tissue may start in these patients, but that the type of genitalia depends on the degree of subsequent degeneration by a gene in DSS.

Abnormalities, Multiple↗