Effect of bosentan on NF-kappaB, inflammation, and tissue factor in angiotensin II-induced end-organ damage

Reports on the effectiveness of endothelin receptor blockers in angiotensin (Ang) II-induced end-organ damage are conflicting, and the mechanisms involved are uncertain. We tested the hypothesis that endothelin (ET)(A/B) receptor blockade with bosentan (100 mg/kg by gavage after age 4 weeks) ameliorates cardiac and renal damage by decreasing inflammation in rats harboring both human renin and angiotensinogen genes (dTGR). Furthermore, we elucidated the effect of bosentan on tissue factor (TF), which is a key regulator of the extrinsic coagulation cascade. We compared bosentan with hydralazine (80 mg/L in the drinking water for 3 weeks) as a blood pressure control. Untreated dTGR featured hypertension, focal necrosis in heart and kidney, and a 45% mortality rate (9 of 20) at age 7 weeks. Compared with Sprague-Dawley controls, both systolic blood pressure and 24-hour albuminuria were increased in untreated dTGR (203+/-8 versus 111+/-2 mm Hg and 67.1+/-8.6 versus 0.3+/-0.06 mg/d at week 7, respectively). Bosentan and hydralazine both reduced blood pressure and cardiac hypertrophy. Mortality rate was markedly reduced by bosentan (1/15) and partially by hydralazine (4/15). However, only bosentan decreased albuminuria and renal injury. Untreated and hydralazine-treated dTGR showed increased nuclear factor (NF)-kappaB and AP-1 expression in the kidney and heart; the p65 NF-kappaB subunit was increased in the endothelium, vascular smooth muscles cells, infiltrating cells, glomeruli, and tubules. In the heart and kidney, ET(A/B) receptor blockade inhibited NF-kappaB and AP-1 activation compared with hydralazine treatment. Macrophage infiltration, ICAM-1 expression, and the integrin expression on infiltrating cells were markedly reduced. Renal vasculopathy was accompanied by increased tissue factor expression on macrophages and vessels of untreated and hydralazine-treated dTGR, which was markedly reduced by bosentan. Thus, ET(A/B) receptor blockade inhibits NF-kappaB and AP-1 activation and the NF-kappaB- and/or AP-1-regulated genes ICAM-1, VCAM-1, and TF, independent of blood pressure-related effects. We conclude that Ang II-induced NF-kappaB and AP-1 activation and subsequent inflammation and coagulation involve at least in part the ET(A/B) receptors.

Bone-muscle strength indices for the human lower leg

This cross-sectional study is based on images from the lower leg as assessed by peripheral quantitative computer tomography (pQCT). Measurements were performed in 39 female and 38 male control subjects and 15 female professional volleyball players, all between 18 and 30 years of age. The images were obtained at shank levels of 4%, 14%, 33%, and 66% from the distal end. Bone and muscle cross-sectional areas, and the bones' density-weighted area moment of resistance and of inertia were assessed. From these, muscle-bone strength indices (MBSIs) were developed for compression (CI = 100. bone area/muscle area) and bending (BI = 100. bone area moment of resistance/muscle area/tibia length). Significant correlations between muscle cross-sectional area and bone were found at all section levels investigated. The strongest correlation for compression was observed in the sections at 14% (correlation coefficient r = 0.74), where 4.10 +/- 0.46 cm(2) bone, on average, was related to 100 cm(2) muscle. The compression index (CI) at the 14% level was independent of the tibia length. Interestingly, the 15 athletes had significantly greater CIs than the control subjects. This is most probably due to the greater tension development in the athletes. The highest correlation for bending was for anteroposterior bending at 33% of tibia length (r = 0.81), where the area moment of resistance, R, was on, average, 4.21 +/- 0.54 cm(3)/100 cm(2) muscle/m tibia length. Analysis of the bones' area moment of inertia showed that buckling is a possible cause of bending at the 33% and 66% levels, but not at the 14% level. No gender differences in MBSI were found. Likewise, age was without significant effect. The data show that bone architecture depends critically on muscle cross section and tension development. Moreover, bone geometry (e.g., the tibia length) influences the geometrical distribution of bone mineral, as it was found that long bones adapted to the same compressive strength are wider than short ones. We conclude that MBSIs offer a powerful diagnostic tool for bone disorders and may contribute to improving the treatment of bone metabolic and other diseases.

Open MRI-guided microsurgery of intracranial tumours. Preliminary experience using a vertical open MRI-scanner

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. The development of open configurated MRI-scanners leads to new perspectives in the intra-operative management and resection control of intracranial tumours.

MATERIAL AND METHOD

Using a vertical open 0.5 T MRI-scanner for intra-operative MR image guided neurosurgery, forty-four patients (20 female/24 male) with different intracranial tumours have been operated on since August 1997. The patients ranged in age from 20 to 70 years (mean +/- standard deviation = 47.2 +/- 15.9 ys).

RESULTS

In 36 (82%) of 44 patients the tumours were completely removed with the aid of MR image-guidance. In 8 cases (18%) complete removal was not achieved. Postoperatively 6 (14%) of 44 patients developed neurological deficits which were transient in 5 cases (paresis, dysphasia). In these patients the tumours were located in or near eloquent brain areas (sensorimotor cortex/speech center).

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 foreward in the field of neurosurgery.

[The radiological and surgical management of nonpalpable breast lesions]

In this retrospective study the results of surgical biopsy of suspected breast cancer in 319 outpatients are reported. In 113 cases (35.4%) the lesion was palpable, in 206 cases (64.6%) it was not. Concerning the nonpalpable lesions, mammography was performed in 98 patients (47.6%) for work-up of fibrocystic changes, in 41 patients (19.9%) for initial participation in a breast cancer prevention program, and in 33 patients (16.0%) for surveillance after breast conservation therapy. Prior to operation, 84.0% (n = 173) of the nonpalpable lesions were detected by mammography, 11.2% (n = 23) by sonography, and 4.8% (n = 10) by magnetic resonance imaging. Intra-operative specimen mammography was carried out in every case detected by mammography. In 19.4% (n = 40) of 206 nonpalpable lesions a malignant tumor was found. Twenty-five percent (n = 10) of all marked tumors were diagnosed and treated as in-situ stage tumors, while 65% (n = 26) were diagnosed and treated as tumors in the pT1 stage. As regards the nodal stage, 85% (n = 34) of the tumors were diagnosed and treated as pNO tumors, and 100% (n = 40) were found to be free from any distant metastases. Consequently, for improving prognosis and, at the same time, for reducing the rate of breast amputations as a means of curative therapy of breast cancer, regular screening in defined risk groups is necessary. Surgical treatment of patients with small and nonpalpable findings should be reserved for departments with marking and quick-freezing facilities.

[Raeder- and Collet-Siccard-Syndrome. Acute pareses of cranial nerves symptomatic of a dissection of internal carotid artery]

Acute cerebral nerve paresis can be caused in many different ways. One of the more rare causes of paresis of one or more neural pathways is dissection of the internal carotid artery. Early diagnosis is important, even with atypical symptoms, since prompt anticoagulative therapy can hinder stroke from embolism due to the dissection. We report on two patients with Raeder's syndrome and Collet-Sicard syndrome resulting from dissection of the internal carotid artery. Besides the cranial and caudal nerves involved in our study, loss of function has also been reported with the sixth to eighth cranial nerves, so that any painful, sudden cranial nerve deficiency can indicate possible carotid dissection.

Evidence for a single-spin azimuthal asymmetry in semi-inclusive pion electroproduction

Single-spin asymmetries for semi-inclusive pion production in deep-inelastic scattering have been measured for the first time. A significant target-spin asymmetry of the distribution in the azimuthal angle straight phi of the pion relative to the lepton scattering plane was formed for pi(+) electroproduction on a longitudinally polarized hydrogen target. The corresponding analyzing power in the sinstraight phi moment of the cross section is 0.022+/-0.005+/-0.003. This result can be interpreted as the effect of terms in the cross section involving chiral-odd spin distribution functions in combination with a chiral-odd fragmentation function that is sensitive to the transverse polarization of the fragmenting quark.

Evidence for a melatonin receptor within pancreatic islets of neonate rats: functional, autoradiographic, and molecular investigations

In a recent perifusion investigation, we showed that the pineal secretory product melatonin reduces insulin secretion from isolated pancreatic islets of neonate rats stimulated with potassium chloride (KCl), glucose, and forskolin. This effect of melatonin was reproduced with doses ranging from 200 pmol/L to 5 micromol/L. Because it is generally accepted that melatonin exerts some of its biological effects through specific, high-affinity pertussis-toxin-sensitive G-protein-coupled receptors, we blocked the putative melatonin receptor of pancreatic islets using both the non-hydrolyzable guanosine triphosphate analog guanosine 5'-O-(3-thiotriphosphate) (GTPgammaS, 30 micromol/L) and the melatonin antagonist luzindole (10 micromol/L). Both GTPgammaS and luzindole caused a near normalization of the melatonin-induced inhibition of the forskolin-stimulated insulin secretion. To localize putative melatonin receptors within the pancreatic islets autoradiographic studies were additionally carried out. These investigations showed specific binding of 2-[125I]iodomelatonin, which were in exact correspondence with the localization of the islets. In addition, gray-level analysis showed that unlabeled melatonin was able to reduce the binding of 2-[125I]iodomelatonin in a dose-dependent manner. Concentrations of unlabeled melatonin of 10(-9) mol/L produced a 50% reduction in specific binding, whereas concentrations of 10(-6) mol/L displaced the binding completely. Likewise, the results of molecular investigations showed that the rat pancreas contains a melatonin receptor, since reverse transcription polymerase chain reaction (RT-PCR) experiments, using specific primers for the rat melatonin receptor Mel1a, showed that mRNA for this melatonin receptor type is expressed in pancreatic tissue of newborn rats. In summary, it may be said that our functional. autoradiographic, and molecular results indicate that the Mel1a receptor is located on the pancreatic islets, possibly in the beta cells.

Detection of BRCA1 and BRCA2 mutations in breast cancer families by a comprehensive two-stage screening procedure

We have developed a 2-stage protocol for BRCA1 and BRCA2 mutation screening from blood spot paper. Stage 1 screening was aimed to analyze patients at highest risk for the most common disease-associated sequence variants listed in the BIC database. Accordingly, stage1 testing implied detection of 18 disease- associated BRCA1 and 9 BRCA2 mutations by adapting the 5' nuclease assay to heterozygote screening. For stage 2 screening, we applied the conformation sensitive gel electrophoresis (CSGE) method by adapting this technique to automated heteroduplex analysis of BRCA1 and BRCA2 using fragment scanning on an ABI 377 sequencing device. Of the 120 patients with a family history of breast and ovarian cancer who took part in this study so far, 45 entered stage 1 testing. Disease-associated mutations were detected in 6 patients by stage 1 testing (13%). For these patients, the final result was available within 10 days. Mutation 300T-->G was found in 2 patients. One patient with mutation 3036delACAA in BRCA2 reported only 1 sister with a multifocal bilateral breast cancer. New disease-associated mutations were detected in 2 of the 114 patients who entered the stage 2 test (1.7%). Of particular interest was 1 patient who was diagnosed with a medullary breast carcinoma at age 39 and who had no family history of breast cancer. We conclude that pre-screening by 5' nuclease assay for the mutations most frequently seen in a given population represents a relatively effective first line of analysis. Subsequent detailed analysis by fluorescence conformation sensitive gel electrophoresis (F-CSGE) and fragment sequencing is a sensitive alternative to full nucleotide sequencing.

Blood pressure-independent effects in rats with human renin and angiotensinogen genes

The blood pressure-independent effects of angiotensin II (Ang II) were examined in double transgenic rats (dTGR) harboring human renin and human angiotensinogen genes, in which the end-organ damage is due to the human components of the renin angiotensin system. Triple-drug therapy (hydralazine 80 mg/L, reserpine 5 mg/L, and hydrochlorothiazide 25 mg/L in drinking water) was started immediately after weaning. Triple-drug therapy normalized blood pressure and coronary resistance, only partially prevented cardiac hypertrophy, and had no effect on ratio of renal weight to body weight. Although triple-drug therapy delayed the onset of renal damage, severe albuminuria nevertheless occurred. Semiquantitative scoring of ED-1-positive and MIB-5-positive (nuclear cell proliferation-associated antigen Ki-67) cells showed profound perivascular monocyte/macrophage infiltration and cell proliferation in kidneys and hearts of untreated dTGR. Triple-drug therapy had only a minimal effect on local inflammatory response or vascular cell proliferation. In contrast, a novel orally active human renin inhibitor (HRI), 30 mg/kg by gavage for 4 weeks, normalized blood pressure and coronary resistance and also prevented cardiac hypertrophy and albuminuria. ED-1-positive cells and MIB-5-positive cells were decreased by HRI in hearts and kidneys almost to levels observed in normotensive Sprague-Dawley rats. The renoprotective effects of HRI were at least in part due to improved renal hemodynamics and distal tubular function, since HRI shifted renal pressure-diuresis/natriuresis curves leftward by approximately 35 mm Hg, increased glomerular filtration rate and renal blood flow, and shifted the fractional water and sodium excretion curves leftward. In untreated dTGR, plasma Ang II was increased by 400% and renal Ang II level was increased by 300% compared with Sprague-Dawley rats. HRI decreased plasma human renin activity by 95% and normalized Ang II levels in both plasma and kidney compared with triple-drug therapy. Our findings indicate that in dTGR harboring human renin and angiotensinogen genes, Ang II causes end-organ damage and promotes inflammatory response and cellular growth largely independent of blood pressure.

Photodynamic therapy for advanced bile duct cancer: evidence for improved palliation and extended survival

Median survival time of nonresectable hilar bile duct cancer is only 4 to 6 months owing to tumor spread in the biliary tree, refractory cholestasis, and sepsis or liver failure. We explored whether local photodynamic therapy of nonresectable bile duct cancer could improve survival. A sample size of 23 patients is required to detect an increase in 6-month survival rate from less than 50% to greater than 70% in a single-arm phase-II trial with a statistical power of 80% (Fleming's single step procedure; alpha = 0.05). Twenty-three consecutive patients (8 women, 15 men; 67 +/- 14 years) with nonresectable bile duct cancer (Bismuth type III n = 2, type IV n = 21) were treated with photodynamic therapy and biliary endoprosthesis. Photofrin (QLT Pharmaceuticals, Vancouver, Canada) (2 mg/kg body weight intravenously) was photoactivated after 1 to 4 days with laser light (630 nm; 242 J/cm(2)) via endoscopic retrograde access. The 6-month survival rate was 91% after diagnosis and 74% after start of photodynamic therapy (30-day mortality rate was 4%) at a median follow-up time of 10.3 months after diagnosis. Causes of death were tumor progression (n = 9) and bacterial infections (n = 4). The median rate of local tumor response was 74%, 54%, 29%, and 67% after the first, second, third, fourth, and fifth photodynamic therapy. Time to progression ranged from 3 to 8 months. All patients, except 1 with diffuse liver metastases, improved in cholestasis, performance, and quality of life. Photodynamic therapy can prevent tumor occlusion of hilar bile ducts. The apparent benefit in survival time should be confirmed in a controlled trial versus palliation by endoprosthesis only.

Adding low-dose antidepressants to interferon alpha treatment for chronic hepatitis C improved psychiatric tolerability in a patient with schizoaffective psychosis

Treatment of chronic hepatitis C with interferon alpha (IFN-alpha) is relatively contraindicated in patients with psychiatric disorders because of possible severe psychiatric side effects. We report on a case of a female patient with a chronic schizoaffective psychosis, who was treated for 3 months with 3 x 3 mio IE IFN-alpha s.c./week because of a chronic hepatitis C (genotype 1b). Psychosis was stable with flupentixol monotherapy. After 2 months, she developed a severe depressive syndrome which lead to suicidal ideation. Until this time, she was without any antidepressive medication. Depressive symptoms disappeared after interferon therapy was stopped. Under prophylactic treatment with low-dose trimipramine (50 mg) or nefazodone (200 mg/day) therapy with IFN-alpha 3 x 3 mio IE/week was re-established after several months and again 2 years later adding ribavirin 1200 mg/day, a virustaticum. In contrast to the symptoms during monotherapy with IFN-alpha, during the time of both combination treatments, no psychiatric side effects occurred. While for ribavirin antidepressant effects are not known, we suppose that antidepressants may prevent changes in serotonergic or noradrenergic neurotransmission caused by IFN-alpha.

A phase II study of pegylated liposomal doxorubicin for treatment of advanced hepatocellular carcinoma

BACKGROUND

Pegylated liposomal doxorubicin has an enhanced efficacy and reduced toxicity compared with free doxorubicin. The efficacy and toxicity of pegylated liposomal doxorubicin was investigated in patients with hepatocellular carcinoma.

PATIENTS AND METHODS

Patients with histologically confirmed, locally advanced or metastatic hepatocellular carcinoma and a Karnofsky index > 60% were included in this prospective single-arm study. Exclusion criteria were liver cirrhosis stage Child-Pugh C, previous chemotherapy, or chemoembolization. Pegylated liposomal doxorubicin was given in a dose of 30 mg/m2 every three weeks until progression of disease. After inclusion of five patients the dose could be escalated to 40 mg/m2 in absence of toxicity grade 3 and 4.

RESULTS

Sixteen patients were evaluable for response. No objective response was achieved. The median survival time was 140 days (95% confidence interval: 126-154 days). Treatment toxicities grade > or = 3 comprised increased liver enzymes in patients with preexisting grade 1 or 2 elevation (n = 6), hematologic toxicity (n = 5), and hypersensitivity (n = 2).

CONCLUSIONS

Pegylated liposomal doxorubicin is not effective for treatment of advanced hepatocellular carcinoma. The favorable toxicity profile was confirmed even in patients with underlying liver disease.

NF-kappaB inhibition ameliorates angiotensin II-induced inflammatory damage in rats

We recently reported that the activation of nuclear factor-kappaB (NF-kappaB) promotes inflammation in rats harboring both human renin and angiotensinogen genes (double-transgenic rats [dTGR]). We tested the hypothesis that the antioxidant pyrrolidine dithiocarbamate (PDTC) inhibits NF-kappaB and ameliorates renal and cardiac end-organ damage. dTGR feature hypertension, severe renal and cardiac damage, and a 40% mortality rate at 7 weeks. Electrophoretic mobility shift assay showed increased NF-kappaB DNA binding activity in hearts and kidneys of dTGR. Chronic PDTC (200 mg/kg SC) treatment decreased blood pressure (162+/-8 versus 190+/-7 mm Hg; P=0.02) in dTGR compared with dTGR controls. The cardiac hypertrophy index was also significantly reduced (4.90+/-0.1 versus 5.77+/-0.1 mg/g; P<0. 001). PDTC reduced 24-hour albuminuria by >95% (2.5+/-0.8 versus 57. 1+/-8.7 mg/d; P<0.001) and prevented death. Vascular injury was ameliorated in small renal and cardiac vessels. Electrophoretic mobility shift assay showed that PDTC inhibited NF-kappaB binding activity in heart and kidney, whereas AP-1 activity in the kidney was not decreased. dTGR exhibited increased left ventricular c-fos and c-jun mRNA expression. PDTC treatment reduced c-fos but not c-jun mRNA. Immunohistochemistry showed increased p65 NF-kappaB subunit expression in the endothelium and smooth muscle cells of damaged small vessels, as well as infiltrating cells in glomeruli, tubules, and collecting ducts of dTGR. PDTC markedly reduced the immunoreactivity of p65. PDTC also prevented the NF-kappaB-dependent transactivation of the intercellular adhesion molecule ICAM-1 and inducible nitric oxide synthase. Monocyte infiltration was markedly increased in dTGR kidneys and hearts. Chronic treatment reduced monocyte/macrophage infiltration by 72% and 64%, respectively. Thus, these results demonstrate that PDTC inhibits NF-kappaB activity, ameliorates inflammation, and protects against angiotensin II-induced end-organ damage.

Cyclosporin A protects against angiotensin II-induced end-organ damage in double transgenic rats harboring human renin and angiotensinogen genes

Leukocyte infiltration and adhesion molecule activation play a central role in the pathogenesis of angiotensin II (Ang II)-induced end-organ damage in double transgenic rats (dTGR) harboring human renin and angiotensinogen genes. We tested the hypothesis that the immunosuppressive agent cyclosporine (CsA) protects against the Ang II-induced myocardial and renal damage in dTGR. Furthermore, we investigated the influence of CsA on interleukin-6 (IL-6) and inducible nitric oxide synthase (iNOS) expression and the DNA binding activity of transcription factor necrosis factor-kappaB (NF-kappaB). The 4-week-old rats were divided into 4 groups: (1) control dTGR (n=20), (2) dTGR plus CsA (5 mg/kg SC for 3 weeks, n=15), (3) normotensive Sprague-Dawley (SD) rats (n=10), and (4) SD rats plus CsA (n=8). In dTGR, CsA completely prevented cardiovascular death (0 of 15 versus 9 of 20), decreased 24-hour albuminuria by 90% and systolic blood pressure by 35 mm Hg, and protected against the development of cardiac hypertrophy. Whole blood CsA concentrations 24 hours after the last drug treatment were 850+/-15 ng/mL. Semiquantitative ED-1 and Ki-67 (a nuclear cell proliferation-associated antigen) scoring showed that CsA prevented perivascular monocyte/macrophage infiltration and prevented cell proliferation in the kidneys and hearts of dTGR, respectively. The beneficial effects of CsA were, at least in part, mediated by the suppression of IL-6 and iNOS expression. Electrophoretic mobility shift assay revealed that CsA regulated inflammatory response in part through the NF-kappaB transcriptional pathway. In contrast to dTGR, CsA increased blood pressure in normotensive SD rats by 10 mm Hg and had no effect on cardiac mass or 24-hour urinary albumin excretion. Perivascular monocyte/macrophage infiltration, IL-6, and iNOS expression or cell proliferation were not affected by CsA in SD rats. Our findings indicate that CsA protects against Ang II-induced end-organ damage and underscore the central role of vascular inflammatory response in the pathogenesis of myocardial and renal damage in dTGR. The beneficial effects of CsA in the kidney and heart are mediated, at least in part, by suppression of IL-6 and iNOS expression via NF-kappaB transcriptional pathway.

The dispute about the external sphincter and the urogenital diaphragm

PURPOSE

Basic scientific facts, such as anatomical structures, are rarely subjected to critical reappraisal. Nevertheless, several clinical phenomena exist which are inconsistent with the description of the anatomy of the so-called external sphincter muscle and urogenital diaphragm.

MATERIALS AND METHODS

We performed a global examination of the anatomy of the entire lower urinary tract in 50 male autopsy specimens. For comparison magnetic resonance imaging of the same regions was performed on 12 healthy patients.

RESULTS

Direct comparison of the results of both methods revealed the exact same topography of the bladder neck. The external sphincter or musculus sphincter urethrae is an independent morphological unit separated from the surrounding pelvic floor muscles by connective tissue.

CONCLUSIONS

The musculus transversus perinei profundus or deep transverse perineal muscle, which is believed to constitute the major element of the urogenital diaphragm, does not exist. There is histomorphological evidence that the external sphincter consists of a striated (musculus sphincter urethrae transversostriatus) and smooth muscle (musculus sphincter urethrae glaber) component.

Open MR imaging in spine surgery: experimental investigations and first clinical experiences

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.

Contrast-enhanced spiral CT of the head and neck: comparison of contrast material injection rates

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.

[MR-track pointer. A reusable device for localization during interventions]

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.

[MR imaging-guided interventions]

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.

Open MRI-guided neurosurgery

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.

High protein/energy vs. standard protein/energy nutritional regimen in the treatment of malnourished hemodialysis patients

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.

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

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.

Chondromatosis of the ankle joint (Reichel syndrome)

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.

Is there a psoriatic osteopathy? -- the activity of bone resorption in psoriatics is related to inflammatory joint process

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.

An automatic method for the identification and interpretation of clustered microcalcifications in mammograms

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.

Preliminary experience with interactive guided brain biopsies using a vertically opened 0.5-T MR system

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.

Application of the ADEPT strategy to the MDR resistance in cancer chemotherapy

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.

Topotecan-based combination chemotherapy for human malignant glioma

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.

[Creatinine and calcium in urine and blood after brief exposure to magnetic fields]

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.

The impact of ergotamine-induced headache and ergotamine withdrawal on information processing

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.

Hypertension-induced end-organ damage : A new transgenic approach to an old problem

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.

Monocyte infiltration and adhesion molecules in a rat model of high human renin hypertension

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.

Medical audit after 26,711 breast imaging studies: improved rate of detection of small breast carcinomas (classified as Tis or T1a,b)

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.]

DNA quantification and ploidy patterns in human adrenocortical neoplasms

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.

Relapse of pulmonary Mycobacterium kansasii disease associated with large-cell cancer of the lung: a case report

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.

Acute effects of recombinant human interleukin-6 on endocrine and central nervous sleep functions in healthy men

Interleukin-6 (IL-6) is a proinflammatory cytokine that has been shown to mediate, in addition to immune reactions, various endocrine and central nervous components of the acute phase response. In this context, the present study aimed to specify the contributions of IL-6 to the regulation of pituitary-adrenal secretory activity and GH and TSH secretion, as well as to the regulation of central nervous sleep and mood in healthy men. Effects of a low dose of IL-6 (0.5 microgram/kg body weight) were assessed, inducing plasma IL-6 concentrations closely comparable with those typically observed after infectious challenge. Each of the 16 male subjects participated in two 14-h sessions (between 1800 and 0800 h), receiving either placebo or human recombinant IL-6 sc at 1900 h. Blood was collected repeatedly to determine plasma hormone levels, serum concentrations of cytokines, and C-reactive protein. Moreover, mood was assessed, and sleep recordings were obtained between 2300 and 0700 h. The cytokine induced a prolonged increased in plasma concentrations of ACTH and cortisol (P < 0.001), but led to a decrease in TSH concentrations (P < 0.01). In response to IL-6, subjects reported fatigue and felt more inactive and less capable of concentrating than after placebo. Sleep architecture was altered significantly by the cytokine. Slow-wave sleep was decreased during the first half and increased during the second half of sleep. Rapid eye movement sleep during the entire nocturnal sleep time was significantly decreased. After IL-6, body temperature rose slightly. C-reactive protein concentrations were dramatically increased 12.5 h after substance administration (P < 0.001). IL-6 did not affect serum concentrations of IL-2, IL-8, interferon-alpha, and interferon-gamma. The results underscore the importance of IL-6 in the cascade of cytokines for the neuroendocrine response during the acute phase reaction. In addition, IL-6 appears to be involved in changes of sleep and behavior accompanying infection and inflammatory disorders.

[New method of MR-guided mammary biopsy]

PURPOSE

With a recently installed new open MR tomograph (Signa SP, General Electric MS) it is possible for the first time to examine patients with obscure lesions of the mamma by MR imaging in a sitting position, similar to mammography.

METHOD

The newly developed positioning device with integrated surface coil permits in combination with the vertical gap in the new magnet and imaging of the mamma with a "real time" sequence a biopsy procedure within a short time and in a manner that is acceptable for the patient. By means of an integrated interactive scan plane guiding system ("flash point tracking system") and special MR-compatible needles and wires tissue samples can be taken, or marking by a wire can be carried out within a short time.

RESULTS

Phantom experiments and first in vivo experience (10 patients) show that by means of the new mamma fixation and biopsy device a MRI of one breast in a sitting position for detecting an enhancing lesion and a MR-guided biopsy of this lesion is possible. The whole procedure takes about 25-35 minutes, comparable to the conventional stereotactic method.

CONCLUSION

Direct patient access and the interactive guided biopsy allow in future both new diagnostic information (histological results after biopsy or after wire-guided open biopsy of a lesion only visible in MR) and the development of minimal invasive therapeutic procedures, e.g. MR-guided and -controlled interstitial thermotherapy.

[Operation of multidisciplinary, interventional 0.5 Tesla magnetic resonance tomograph. Technical and logistic problems and initial clinical results]

Multidisciplinary usage of a MRI system with a superconducting 0.5-T magnet (Signa SP, General Electric) with a vertical gap suited for diagnostic and therapeutic interventions raises complex problems. The MR equipment, including a special localizing system and the instruments for diagnostic and therapeutic interventions, is described. Before putting the system into operation tests were necessary to check MR compatibility of various materials and instruments and to build some auxiliary equipment. We report on the coordinating activities of the radiologist in the context of MR use by different medical specialities. Within the course of 12 months, 428 examinations/interventions of different kinds were carried out, among them 75 functional examinations of the spine or of joints, 31 diagnostic biopsies, 23 cerebral biopsies, and 23 operations. The special design of the Signa SP allows the whole scale of functional examinations, up to complete neurosurgical interventions, in the sitting position and under nearly real-time imaging control.

Theory and application of passive SAW radio transponders as sensors

Surface acoustic wave (SAW) radio transponders make it possible to read identification codes or measurement values from a remote location. The decisive advantage of these SAW transponders lies in their passive operation (i.e., no power-supply), and in the possibility of wireless installation at particularly inaccessible locations. The passive SAW transponders are maintenance free. Identification marks respond to an interrogation signal with their nonchanging identification pattern. In wireless SAW sensors the physical or chemical properties to be detected change the propagation characteristics of the SAW. SAW radio transponders are advantageously placed on moving or rotating parts and in hazardous environments such as contaminated or high voltage areas. They also can be used for contactless measurements in high vacuum process chambers, under concrete, extreme heat, or strong radioactive radiation, where the use of conventional sensors is complicated, dangerous, or expensive. In this paper we discuss the principles of wireless passive SAW transponders and present a radio frequency interrogation unit and several passive radio SAW sensors developed for noncontact measurements of temperatures, pressures, torques, and currents.

[Radiologic imaging of MALT lymphoma. (Comparison between stomach roentgen image, computerized tomography and magnetic resonance tomography]

The new classification of primary lymphomas of the stomach according to the MALT concept is very promising in therapy planning and prognostic estimation. This new classification sets strict requirements for imaging diagnostics. Besides endosonography which allows the determination of the infiltration depth in stages E I1 and E I2 in an excellent manner, computed tomography and, possibly, magnetic resonance tomography are indispensible for evaluation of higher stages and of the resectability of a lymphoma. Further MRI examinations are recommended.