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Verheyden P, Katscher S, Schulz T, Schmidt F, Josten C. Open MR imaging in spine surgery: experimental investigations and first clinical experiences. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 1999; 8:346-53. [PMID: 10552316 PMCID: PMC3611200 DOI: 10.1007/s005860050186] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
INTRODUCTION The latest open MRI technology allows to perform open and closed surgical procedures under real-time imaging. Before performing spinal trauma surgery preclinical examinations had to be done to evaluate the artifacts caused by the implants. METHODS The MRT presented is a prototype developed by GE. Two vertically positioned magnetic coils are installed in an operation theater. By that means two surgeons are able to access the patient between the two coils. Numerous tests regarding the material of instruments and implants were necessary in advance. The specific size of the artifact depending on the pulse sequence and the positioning within the magnetic field had to be examined. RESULTS The magnifying factors of the artifact in the spin echo sequence regarding titanium are between 1.7 and 3.2, depending on the direction of the magnetic vector. Regarding stainless steel they are between 8.4 and 8.5. In the gradient echo sequence the factors are between 7.5 and 7.7 for titanium and between 16.9 and 18.0 for stainless steel. The tip of an implant is imaged with an accuracy of 0 to 2 mm. Since September 1997 16 patients with unstable fractures of the thoracic and lumbar spine have been treated by dorsal instrumentation in the open MRI. Percutaneous insertion of the internal fixator has proven a successful minimally invasive procedure. The positioning of the screws in the pedicle is secure, the degree of indirect reduction of the posterior wall of the vertebral body can be imaged immediately. The diameter of the spinal canal can be determined in any plane. DISCUSSION AND CONCLUSION The open MRI has proven useful in orthopedic and trauma surgery. The size and configuration of the artifacts caused by instruments and implants is predictable. Therefore exact positioning of the implants is achieved more easily. Dorsal instrumentation of unstable thoracolumbar fractures with a percutaneous technique has turned out safe and less traumatic under MR-imaging. Real-time imaging of soft tissue and bone in any plane improves security for the patient and allows the surgeon to work less invasively and more precisely.
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Groell R, Willfurth P, Schaffler GJ, Mayer R, Schmidt F, Uggowitzer MM, Tillich M, Genser B. Contrast-enhanced spiral CT of the head and neck: comparison of contrast material injection rates. AJNR Am J Neuroradiol 1999; 20:1732-6. [PMID: 10543650 PMCID: PMC7056187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
BACKGROUND AND PURPOSE Contrast-enhanced spiral CT studies of the head and neck are performed frequently using contrast material volumes of approximately 30 g iodine and a scan delay of 30-45 seconds. Because little is known about the effects of contrast material injection rates on tissue enhancement, this was prospectively investigated in our study. METHODS Ninety-seven patients underwent spiral CT of the head and neck. Each patient was assigned randomly to one of four groups who received 100 mL of nonionic contrast material (300 mg I/mL) at different monophasic injection flow rates with 1.5, 2, 3, and 4 mL/s. Scanning started after a constant delay of 35 seconds. The attenuation of the carotid artery, jugular vein, and sternocleidomastoid muscle was measured over time and the attenuation of the submandibular and thyroid gland was evaluated. Vascular attenuation of at least 150 HU was considered to be sufficient. RESULTS The mean scan time was 33+/-5 seconds. The study, using an injection rate of 2 mL/s, showed the longest time of sufficient overall (arterial and venous) vessel attenuation (27+/-4 seconds, P< or =.008). The injection flow rate did not influence significantly muscular attenuation (mean enhancement during scan time: 9+/-7 HU). The 1.5 mL/s protocol showed the lowest attenuation values of the submandibular gland (81+/-12 HU) and the highest attenuation values of the thyroid gland (164+/-22 HU), but the attenuation of the thyroid gland was not statistically different from that revealed by the 2 mL/s protocol. CONCLUSION Using 100 mL of intravenous contrast material with 300 mg I/mL for spiral CT studies of the entire head and neck, the optimal injection flow is 2 mL/s, whereas lower flow rates resulted in insufficient venous enhancement.
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Schulz T, Schneider JP, Winkel A, Daum W, Trantakis C, Bootz F, Laufer M, Dietrich J, Schmidt F. [MR-track pointer. A reusable device for localization during interventions]. ROFO-FORTSCHR RONTG 1999; 171:244-8. [PMID: 10520336 DOI: 10.1055/s-1999-11088] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
PURPOSE Development of an helpful instrument for a better planning and orientation during MR guided interventions. MATERIAL AND METHODS We developed a reusable, sterilizable instrument that can be filled both with a solution of Gd-DTPA (1%) and with a sodium chloride solution (0.9%). The pointer has a diameter of 3 and 5 mm resp. and its length is 100-150 mm. The instrument can be combined with an interactive stereotactic tracking device. RESULTS The MR-Track-Pointer can be fixed to the two handpieces of the integrated interactive tracking system without problems. The pointer can be seen both on T1w and T2w sequences inside and outside of the tissue. This new instrument can be interactively used for reliable planning the biopsy trajectory, planning craniotomies and identifying structures which are only visible on MR images. CONCLUSIONS The MR-Track-Pointer is an ideal supplement for the integrated virtual tracking system. It permits a minimal invasive orientation and facilitates the exact localisation of suspect lesions in sensible regions during MR guided interventions, e.g. diagnostic biopsies and tumour resections.
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Abstract
The spectrum of MR imaging-guided interventions includes biopsies, thermal ablation modalities, vascular applications, MR endoscopy and intraoperative MR imaging. The concept of MR guidance is based on the excellent morphologic and functional imaging achieved by MR. The most important recently published experimental and clinical results are discussed. In the future, MR imaging will play an important role in interventional radiology, minimal invasive therapy and guidance of surgical procedures.
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Seifert V, Zimmermann M, Trantakis C, Vitzthum HE, Kühnel K, Raabe A, Bootz F, Schneider JP, Schmidt F, Dietrich J. Open MRI-guided neurosurgery. Acta Neurochir (Wien) 1999; 141:455-64. [PMID: 10392200 DOI: 10.1007/s007010050325] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
OBJECTIVES A number of different image-guided surgical techniques have been developed during the past decade. None of these methods can provide the surgeon with information about the dynamic changes that occur intra-operatively. MATERIAL AND METHOD The first vertical open 0.5T MRI-scanner for intra-operative MRI-guided neurosurgery in Germany was installed at the University of Leipzig during the summer 1996. Since autumn 1996 a number of surgical procedures including biopsies (n = 31), craniotomies (n = 32), transsphenoidal procedures (n = 8) and interstitial lasertherapies (n = 3) have been performed using intra-operative MR image guidance. RESULTS The development of MR-compatible and MR-safe non-magnetic instruments and components had to be solved. Specific surgical instruments were developed to perform biopsies, craniotomies, microsurgical tumour resections and transsphenoidal procedures in the 0.5-T open MRI. Several components required adaptation including the head holder the stereotactic navigation device, the high speed drill, the suction unit, the ultrasonic aspirator, the bipolar coagulation, the laser probe and the surgical microscope. All these newly developed technical features enable the neurosurgeon to perform a large number of surgical procedures under direct control and guidance of intra-operative MR imaging. In contrast to frame-based for framless navigation systems, intra-operative MRI provides accurate and immediate information during the progress of surgery. These intra-operative images allow definitive localization and targeting of the lesions and accommodate anatomical changes that may occur during surgery. CONCLUSION Intra-operative MRI is helpful for navigation as well as determining of tumour margins to achieve a complete and safe resection of intracranial lesions. Complications related to the surgical procedure are reduced and the risk of neurological deterioration due to tumour removal and postoperative complications is minimized. It can be concluded that the intra-operative application of interventional MRI technology may represent a major step forward in the field of neurosurgery.
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Kuhlmann MK, Schmidt F, Köhler H. High protein/energy vs. standard protein/energy nutritional regimen in the treatment of malnourished hemodialysis patients. MINERAL AND ELECTROLYTE METABOLISM 1999; 25:306-10. [PMID: 10681657 DOI: 10.1159/000057465] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Although malnutrition is frequently encountered in maintenance hemodialysis (MHD) patients, a clear method of treating this complication is still lacking. Failure of nutritional support regimens may be due to inadequate support of dietary needs. Therefore, a high vs. standard or low protein/energy dietary regimen was studied in malnourished MHD patients. A total of 18 malnourished MHD patients selected according to subjective global assessment (SGA)-scores and biochemical indicators of malnutrition (serum albumin <40 g/l, cholesterol <200 mg/dl, prealbumin <30 mg/dl; two out of three) were assigned to three treatment groups: (A: 45 kcal/kg/d and 1.5 g protein/kg/d; B: 35 kcal/kg/d and 1.2 g protein/kg/d; C: spontaneous intake supplemented with 10% of mean protein and energy intake). A and B received food supplements at appropriate dosing to reach the targeted nutritional intake. During 3-month follow-up nutrient intake was assessed by repeated 4-day dietary diaries. Compliance and tolerance was good in each group. Weight gain (1.2+/-0.4 kg) was observed in group A, but not in B and C. Serum albumin levels increased by 1.0+/-0.5 g/l in group A, but not in B and C. Prealbumin and cholesterol levels were unaffected. Weight change correlated with mean dietary energy intake, but not with mean dietary protein intake. We conclude that prescription of 45 kcal/kg/d and 1.5 g protein/kg/d may be necessary to achieve weight gain and improvement of nutritional indices in malnourished MHD pts. Oral food supplements can be used safely and effectively to increase nutrient intake to high levels in these patients.
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Behr TM, Memtsoudis S, Vougioukas V, Liersch T, Gratz S, Schmidt F, Lorf T, Post S, Wörmann B, Hiddemann W, Ringe B, Becker W. Radioimmunotherapy of colorectal cancer in small volume disease and in an adjuvant setting: preclinical evaluation in comparison to equitoxic chemotherapy and initial results of an ongoing phase-I/II clinical trial. Anticancer Res 1999; 19:2427-32. [PMID: 10470170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
The 5-year survival of colorectal cancer patients with distant metastases is below 30%, despite the development and use of a variety of chemotherapeutic regimens. Therefore, new therapeutic strategies are warranted. Whereas radioimmunotherapy (RIT) has shown disappointing results in bulky disease, it may be a promising therapeutic alternative in limited and small volume disease. The aim of this study was, therefore, to compare, in a preclinical study, the therapeutic efficacy of RIT in colorectal cancer to equitoxic chemotherapy, as well as to evaluate, in a pilot clinical trial, its efficacy in small volume disease. Nude mice, bearing subcutaneous or metastatic human colon cancer xenografts, were injected either with the unlabeled or 131I-labeled monoclonal antibodies (MAbs), CO17-1A (which is a murine IgG2a directed against a 41-kD membrane glycoprotein) or F023C5 (which is an anti-CEA MAb of murine IgG1 subtype), or were administered 5-fluorouracil/folinic acid (5-FU/LV) at equitoxic doses. In a pilot clinical study, 10 colorectal cancer patients with small volume metastatic disease (all lesions < or = 3 cm) have been entered so far in an ongoing mCi/m2-based dose escalation study with the 131I-labeled F023C5. In the animals, the maximum tolerated activities (MTD) of 131I-labeled CO17-1A and F023C5 were 300 microCi and 600 microCi, respectively, corresponding to blood doses of approximately 15 Gy each. Accordingly, myelotoxicity was dose-limiting. The MTD in the chemotherapy group was 0.6 mg 5-FU/1.8 mg LV, given as intravenous bolus 1 h apart for 5 subsequent days. Whereas no significant therapeutic effects were seen with both unlabeled MAbs or 5-FU/LV chemotherapy, tumor growth was retarded significantly with both radiolabeled antibodies. In the metastatic model, chemotherapy prolonged life for only a few weeks, whereas RIT led to cures in 35-55% of the animals. As was the case in the animals, myelotoxicity seems to be dose-limiting in patients as well. Encouraging anti-tumor effects were observed, lasting for up to more than 12 months. These data suggest that radioimmunotherapy may be a viable therapeutic option in colorectal cancer patients with limited disease. Myelotoxicity is the only dose-limiting organ toxicity. Although most patients were treated below the MTD, anti-tumor effects are encouraging. Further studies are ongoing.
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Wagner S, Bennek J, Gräfe G, Schmidt F, Thiele J, Wittekind C, Meier T. Chondromatosis of the ankle joint (Reichel syndrome). Pediatr Surg Int 1999; 15:437-9. [PMID: 10415314 DOI: 10.1007/s003830050627] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
A case of chondromatosis of the upper ankle joint in childhood is described. It is a monoarticular disease with a good prognosis, frequently without known prior trauma or inflammation, although often free fragments of cartilage are seen in the joint cavities. It originates from the synovium of the joint, and is known in the literature as Reichel syndrome.
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Hein G, Schmidt F, Barta U, Müller A. Is there a psoriatic osteopathy? -- the activity of bone resorption in psoriatics is related to inflammatory joint process. Eur J Med Res 1999; 4:187-92. [PMID: 10336408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Abstract
The aim of this study was to examine former own histomorphological results by using biochemical markers of bone collagen catabolism in patients with psoriasis vulgaris and psoriatic arthritis and to compare these results with those from rheumatoid arthritis. - The diagnosis of PsA was made according to the diagnostic criteria of Moll and Wright modified by Bennet. Urine was collected from 99 patients with PsA, 21 patients suffering from PS without articular manifestations, 154 patients with RA fulfilling the ACR criteria of 1987, and 80 healthy controls. Pyridinoline and deoxypyridinoline in urine were analyzed by HPLC, levels of CrP and ESR were estimated using laboratory assessment. - Both crosslinks show a elevated excretion in PsA (particularly in active PsA / aPsA) as well as in RA. PS and Controls show no significant difference in the elimination of crosslinks. The levels of both crosslinks are higher in females than males in all groups. With the exception of Dpyd levels in urine which only show a tendency to correlate with ESR, there are positive correlations between measured crosslink-levels in urine and markers of inflammation. The Pyd/Dpyd ratio displays a significant correlation with ESR. - An increased breakdown of collagen I and II was found only in active forms of psoriatic arthritis and in rheumatoid arthritis. Our biochemical results do not demonstrate a complete agreement with former scintigraphic or histological investigations of other authors and own histomorphological results.
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Schmidt F, Sorantin E, Szepesvàri C, Graif E, Becker M, Mayer H, Hartwagner K. An automatic method for the identification and interpretation of clustered microcalcifications in mammograms. Phys Med Biol 1999; 44:1231-43. [PMID: 10368015 DOI: 10.1088/0031-9155/44/5/011] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We investigated a method for a fully automatic identification and interpretation process for clustered microcalcifications in mammograms. Mammographic films of 100 patients containing microcalcifications with known histology were digitized and preprocessed using standard techniques. Microcalcifications detected by an artificial neural network (ANN) were clustered and some cluster features served as the input of another ANN trained to differentiate between typical and atypical clusters, while others were fed into an ANN trained on typical clusters to evaluate these lesions. The measured sensitivity for the detection of grouped microcalcifications was 0.98. For the task of differentiation between typical and atypical clusters an Az value of 0.87 was computed, while for the diagnosis an Az value of 0.87 with a sensitivity of 0.97 and a specificity of 0.47 was obtained. The results show that a fully automatic computer system was developed for the identification and interpretation of clustered microcalcitications in mammograms with the ability to differentiate most benign lesions from malignant ones in an automatically selected subset of cases.
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Schneider JP, Dietrich J, Lieberenz S, Schmidt F, Sorge O, Trantakis C, Seifert V, Kellermann S, Schober R, Franke P. Preliminary experience with interactive guided brain biopsies using a vertically opened 0.5-T MR system. Eur Radiol 1999; 9:230-6. [PMID: 10101643 DOI: 10.1007/s003300050660] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The purpose of our study was to evaluate the feasibility and accuracy of brain biopsies performed within a vertically opened MR system. We worked with the interventional 0.5-T MR "SIGNA SP" (General Electric Medical Systems, Milwaukee, Wis.) with an integrated tracking device "Flashpoint Position Encoder" (Image Guided Technologies, USA). As a holding device for this instrument we constructed a special frame. The whole system allows an exact adjustment of an optimum biopsy direction and guidance of the biopsy in a non-stereotactic, interactive mode in near real-time. As biopsy tools we used MR-compatible aspiration and specially made side-cut needles (Daum, Germany; E-Z-EM, USA). We performed a prospective diagnostic brain biopsy study in 18 patients. Guidance of the needle was carried out using gradient-echo single-slice technique. The sample was taken after controlling the exact position of the needle tip on spin-echo images. In 12 cases an exact neuropathological diagnosis was possible. In 6 cases of negative biopsy (4 aspiration biopsies) the samples were not representative. Our results demonstrate the feasibility of interactive MR-guided minimally invasive brain biopsies in an open MR system. The best results were achieved using cut needles for biopsies of contrast-enhancing lesions visible on T1-weighted gradient-echo guidance sequence.
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Desbene S, Van HD, Michel S, Tillequin F, Koch M, Schmidt F, Florent JC, Monneret C, Straub R, Czech J, Gerken M, Bosslet K. Application of the ADEPT strategy to the MDR resistance in cancer chemotherapy. ANTI-CANCER DRUG DESIGN 1999; 14:93-106. [PMID: 10405636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
New prodrugs consisting of a beta-D-glucuronic acid linked to a MDR reversal agent (verapamil, quinine or dipyridamole) through a self-immolative spacer were synthesized. Four of them were selected for their reduced cytoxicity and beta-glucuronidase enzymatic efficient hydrolysis. Combined use of these prodrugs with a beta-D-glucuronyl-spacer-doxorubicin (HMR1826) according to an ADEPT strategy restored in vitro the sensibility of a MDR resistant strain.
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Schmidt F, Schuster M, Streffer J, Schabet M, Weller M. Topotecan-based combination chemotherapy for human malignant glioma. Anticancer Res 1999; 19:1217-21. [PMID: 10368678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
BACKGROUND Topotecan has been considered a promising agent for the adjuvant chemotherapy of human malignant glioma because of its novel mode of action, its activity against other solid tumors, and its good penetration across the blood-brain barrier. However, the clinical effects of topotecan monotherapy in malignant glioma have been disappointing. MATERIALS AND METHODS We sought to identify suitable partners for topotecan combination chemotherapy of malignant glioma using two well-characterized human malignant glioma cell lines, T98G and LN-229. The effects of co-exposure to topotecan and other chemotherapy drugs were assessed in cytotoxic and clonogenic cell death assays. RESULTS We found additive, less-than-additive, or occasional antagonistic effects, but never synergistic activity of topotecan with either CCNU, VM26 or vincristine, in acute cytotoxicity or in clonogenic cell death assays, with simultaneous or sequential drug exposure. VM26 or vincristine followed by topotecan yielded the most favourable results. Further, prolonged exposure of the glioma cells to topotecan and either CCNU, VM26, vincristine, cisplatin, doxorubicin or cytarabine resulted in additive but not synergistic growth inhibition. CONCLUSIONS The present study fails to identify a specific partner for topotecan-based combination chemotherapy of malignant glioma among the chemotherapeutic drugs examined here. While this does not exclude a possible synergy of the drug combinations examined here in vivo, a focus on novel partners for topotecan or topotecan-based chemoimmunotherapy may be more promising.
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Schulz T, Prietzel T, Bier T, Mühlig K, Schmidt F. [An intraosseous lipoma of the calcaneus]. ROFO-FORTSCHR RONTG 1999; 170:324-5. [PMID: 10230445 DOI: 10.1055/s-2007-1011048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Schmidt F, Mannsåker T, Løvlie R. [Creatinine and calcium in urine and blood after brief exposure to magnetic fields]. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 1999; 119:491-4. [PMID: 10081371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
In this experimental study, 35 males were exposed to artificial magnetic fields. The fields were produced by a set of Helmholz coils internally isolated by a Faraday cage which effectively eliminated electrical fields. Each participant stayed inside the coils for 40 minutes on two occasions with an interval of seven days, but was actually only once exposed to a static magnetic field (9.6 mT) and oscillating magnetic fields of variable frequency and strength. Urine and blood samples were taken before and after exposure, and before and after non-exposure. Analysis detected significant changes in serum creatinine level after exposure (p < 0.0001). The changes in serum creatinine level in the nonexposed situation were significantly smaller than the changes found in the exposed situation (p < 0.0001). The changes i urine creatinine after 40 minutes of exposure was also found to be significant (p < 0.01). Exposure to magnetic fields may induce biological reactions.
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Evers S, Schmidt F, Bauer B, Voss H, Grotemeyer KH, Husstedt IW. The impact of ergotamine-induced headache and ergotamine withdrawal on information processing. Psychopharmacology (Berl) 1999; 142:61-7. [PMID: 10102783 DOI: 10.1007/s002130050862] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Ergotamine abuse and subsequent ergotamine-induced headache is a common problem in the pharmacological treatment of migraine and other headache types; often, withdrawal therapy is necessary. This study investigated whether ergotamine abuse affects information processing and whether withdrawal therapy can lead to an improvement of information processing. We designed a standardized neurophysiological retrospective (ergotamine abuse) and prospective (ergotamine withdrawal) study in a supraregional headache outpatient clinic. Seventy-one patients abusing ergotamine derivatives with subsequent daily headache were enrolled and compared to 36 migraine patients without ergotamine intake and 36 healthy subjects. Information processing was evaluated by latencies and amplitudes of visually evoked event-related potentials (ERP) before and after ergotamine withdrawal therapy. P3 latency of the ERP was significantly increased in ergotamine abuse (442 +/- 45 ms) versus migraine (415 +/- 40 ms) and healthy subjects (410 +/- 33 ms), there was no difference between ergotamine tartrate and dihydroergotamine abuse. The migraine specific loss of habituation in information processing as measured by P3 latency could not be observed in migraine patients with ergotamine abuse. After successful withdrawal therapy in 36 patients, the abnormally prolonged P3 latency was significantly shortened (452 +/- 47 ms versus 433 +/- 30 ms; P < 0.004). Our findings imply that information processing is impaired by ergotamine abuse and can be improved but not normalized after withdrawal therapy. Furthermore, our data provide strong evidence that ergotamine, besides its peripheral effects, has a central mode of action.
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Berr F, Wiedmann M, Mössner J, Tannapfel A, Schmidt F. Detection of cholangiocarcinoma in primary sclerosing cholangitis by positron emission tomography. Hepatology 1999; 29:611-3. [PMID: 10026030 DOI: 10.1002/hep.510290210] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
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Luft FC, Mervaala E, Müller DN, Gross V, Schmidt F, Park JK, Schmitz C, Lippoldt A, Breu V, Dechend R, Dragun D, Schneider W, Ganten D, Haller H. Hypertension-induced end-organ damage : A new transgenic approach to an old problem. Hypertension 1999; 33:212-8. [PMID: 9931107 DOI: 10.1161/01.hyp.33.1.212] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Angiotensin (Ang) II-induced organ damage has fascinated students of hypertension since the work of Wilson and Byrom. We are investigating a double transgenic rat (dTGR) model, in which rats transgenic for the human angiotensinogen and renin genes are crossed. These rats develop moderately severe hypertension but die of end-organ cardiac and renal damage by week 7. The heart shows necrosis and fibrosis, whereas the kidneys resemble the hemolytic-uremic syndrome vasculopathy. Surface adhesion molecules (ICAM-1 and VCAM-1) are expressed early on the endothelium, while the corresponding ligands are found on circulating leukocytes. Leukocyte infiltration in the vascular wall accompanies PAI-1, MCP-1, and VEGF expression. The expression of TGF-beta and deposition of extracellular matrix proteins follows, which is accompanied by fibrinoid vasculitis in small vessels of the heart and kidneys. Angiotensin-converting enzyme inhibitors and AT1 receptor blockers each lowered blood pressure and shifted pressure natriuresis partially leftward by different mechanisms. When combined, they normalized blood pressure, pressure natriuresis, and protected from vasculopathy completely. Renin inhibition lowered blood pressure partially, but protected from vasculopathy completely. Endothelin receptor blockade had no influence on blood pressure but protected from vasculopathy and improved survival. We show evidence that Ang II stimulates oxidative stress directly or indirectly via endothelin 1 and that NFkappaB is upregulated in this model. We speculate that the transcription factors NFkappaB and AP-1 are involved with initiating chemokine and cytokine expression, leading to the above cascade. The unique model and our pharmacological probes will enable us to test these hypotheses.
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Mervaala EM, Müller DN, Park JK, Schmidt F, Löhn M, Breu V, Dragun D, Ganten D, Haller H, Luft FC. Monocyte infiltration and adhesion molecules in a rat model of high human renin hypertension. Hypertension 1999; 33:389-95. [PMID: 9931135 DOI: 10.1161/01.hyp.33.1.389] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Hypertension and kidney damage in the double transgenic rat (dTGR) harboring both human renin and human angiotensinogen genes are dependent on the human components of the renin angiotensin system. We tested the hypothesis that monocyte infiltration and increased adhesion molecule expression are involved in the pathogenesis of kidney damage in dTGR. We also evaluated the effects of long-term angiotensin-converting enzyme (ACE) inhibition, AT1 blockade, and human renin inhibition on monocyte recruitment and inflammatory response in dTGR. Systolic blood pressure and 24-hour albuminuria were markedly increased in 7-week-old dTGR as compared with age-matched normotensive Sprague Dawley rats. We found a significant monocyte/macrophage infiltration in the renal perivascular space and increased expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in the interstitium, intima, and adventitia of the small renal vessels. alphaLbeta2 integrin and alpha4beta1 integrin, the corresponding ligands for ICAM-1 and VCAM-1, were also found on infiltrating monocytes/macrophages. The expression of plasminogen activator inhibitor-1 and fibronectin in the kidneys of dTGR were increased and distributed similarly to ICAM-1. In 4-week-old dTGR, long-term treatment with ACE inhibition (cilazapril), AT1 receptor blockade (valsartan), and human renin inhibition (RO 65-7219) (each drug 10 mg/kg by gavage once a day for 3 weeks) completely prevented the development of albuminuria. However, only cilazapril and valsartan were able to decrease blood pressure to normotensive levels. Interestingly, the drugs were all equally effective in preventing monocyte/macrophage infiltration and the overexpression of adhesion molecules, plasminogen activator inhibitor-1, and fibronectin in the kidney. Our findings indicate that angiotensin II causes monocyte recruitment and vascular inflammatory response in the kidney by blood pressure-dependent and blood pressure-independent mechanisms. ACE inhibition, AT1 receptor blockade, and human renin inhibition all prevent monocyte/macrophage infiltration and increased adhesion molecule expression in the kidneys of dTGR.
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Schmidt F, Hartwagner KA, Spork EB, Groell R. Medical audit after 26,711 breast imaging studies: improved rate of detection of small breast carcinomas (classified as Tis or T1a,b). Cancer 1998; 83:2516-20. [PMID: 9874457 DOI: 10.1002/(sici)1097-0142(19981215)83:12<2516::aid-cncr16>3.0.co;2-#] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Patients with breast carcinomas 1 cm or smaller are known to have the highest long term survival rates. This pathologic measurement was used as a quality indicator of the performance of different reporting radiologists. METHODS A total of 26,711 diagnostic breast imaging studies were performed over a period of 5 years. Within the first 18 months, several general radiologists reported mammograms, whereas during the rest of the evaluated period only 1 radiologist was responsible for all mammography reporting. Radiologic findings leading to open biopsy were correlated with the histologic results. The cancer sizes from the histologic reports were recorded, and the number of Tis, T1a, and T1b cancers were correlated with all cancers found at open biopsy. The change in the relative percentage of small cancers was evaluated, along with the positive predictive value (PPV). RESULTS Between 1991 and 1995, 26,711 breast imaging studies were performed. This resulted in 2698 open biopsies with 620 breast carcinomas detected. In the first 2 years, the percentages of small cancers detected (Tis or T1a,b) were 27.2% and 25.7%, respectively. In the third, fourth, and fifth years, the percentages increased to 38.8%, 34.5%, and 38.8%, respectively. At the same time, the PPV increased slightly, from 0.23 in 1991 to 0.27 in 1995. CONCLUSIONS The detection of curable early stage breast carcinomas requires the dedication and commitment of a small group of radiologists who are willing to spend most of their time on this single subject. This will increase considerably the number of early stage cancers found and reduce the number of false-positive diagnoses. [See editorial counterpoint on pages 2430-1 and reply to counterpoint on pages 2432-3.]
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Berr F, Schmidt F. Hilar bile duct carcinoma. J Hepatol 1998; 29:826. [PMID: 9833922 DOI: 10.1016/s0168-8278(98)80265-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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Pignatelli D, Leitão D, Maia M, Schmidt F. DNA quantification and ploidy patterns in human adrenocortical neoplasms. Endocr Res 1998; 24:869-74. [PMID: 9888590 DOI: 10.3109/07435809809032700] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The determination of DNA ploidy and the study of the cell cycle in adrenocortical tumoral cells could help in the distinction between benign and malignant lesions and also in the prediction of the biological behaviour of these tumors. We analysed 32 cases of adrenal tissue (8 normal adrenals--N, 12 benign adenomas--A and 12 carcinomas--C). DNA was quantified by image analysis of Feulgen stained sections (Ahrens System) employing ACAS3 software. The DNA content was considered to be diploid in 70% of the N and in 67% of the A groups and in none of C. In this latter group nearly 90% were triploid or tetraploid while this did not occur in any of the A cases. The percentage of cases with a 5c-exceeding rate (5cER) above 5% was nil in the N and A groups and 100% in C. In what concerns the distribution in the cell cycle we found a very distinctive pattern between the groups as the percentage of cases in which the S-phase fraction exceeded 33% was nil in the normals, 8% in A and 83% in the C cases. In conclusion, there was a good correlation between the analysed parameters and the clinically defined groups of adrenal cortex tumors.
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Domej W, Maier A, Schmidt F, Dimai HP, Wirnsberger GH. Relapse of pulmonary Mycobacterium kansasii disease associated with large-cell cancer of the lung: a case report. Oncol Rep 1998; 5:853-6. [PMID: 9625831 DOI: 10.3892/or.5.4.853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A 43-year-old caucasian male diabetic presented with purulent cough and a history of weight-loss, elevated temperature, night-sweat and dyspnea. Four years previously, the patient had undergone a 12-month antimycobacterial regimen because of pulmonary mycobacterium kansasii (MK) disease of the left upper lobe (LUL). Treatment had led to complete recovery with the exception of minor fibrous residuals in the involved pulmonary segments. Chest radiograph and computed tomography (CT), performed on recent admission, revealed a dense infiltration of these residual-containing segments. Microbiological evaluation of bronchial brushings, aspirates and histology of the transbronchial biopsies indicated a relapse of pulmonary MK disease. Although antimycobacterial treatment was started immediately, therapeutic effects were only minimal and remained to be limited to the initial phase of the treatment. After four weeks of treatment, the patient's general condition worsened again. Follow-up CT of the lung showed a marked increase of the infiltration in the left apicoposterior lobe and re-bronchoscopy showed a tumorous protrusion of the bronchial wall involving the apicoposterior segment ostium, a finding which was not seen in the previous bronchoscopy. Histology of the transbronchial biopsies revealed a carcinoma mainly from large-cell type.
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Grupp C, Schmidt F, Braun F, Lorf T, Ringe B, Müller GA. Haemolytic uraemic syndrome (HUS) during treatment with cyclosporin A after renal transplantation--is tacrolimus the answer? Nephrol Dial Transplant 1998; 13:1629-31. [PMID: 9681701 DOI: 10.1093/ndt/13.7.1629] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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