Open MRI-guided microsurgery of intracranial tumours in or near eloquent brain areas

OBJECTIVES

Preservation of brain function while maximizing resection is the main aim of brain tumour surgery. The purpose of this study was to evaluate the efficacy of intra-operative magnetic resonance imaging to preserve brain function in patients with tumours in or near eloquent brain areas.

METHODS AND MATERIAL

Between August 1997 and January 1999 fifty-eight craniotomies for intracranial tumours or vascular malformations have been performed at the University of Leipzig using a 0.5 T superconducting MR system "SIGNA SP" (General Electric Medical Systems, USA). In 32 of these patients (15 male/17 female) with intracranial tumours, located in or near eloquent brain areas (sensorimotor cortex/speech center), 34 craniotomies were performed using the image guidance of the interventional MRI.

RESULTS

Using intra-operative MRI criteria, complete tumour removal could be achieved in 28 (82%) of 34 procedures. In 3 patients only subtotal tumour removal was possible, because the residual tumour was not visible on the intra-operative MR images, but could be identified on early diagnostic follow-up MR-scans. In 3 patients, incomplete tumour resection was performed in order to avoid neurological impairment. In these patients intra-operative MR-images revealed residual tissue abnormalities involving or encroaching on deep brain structures or motor/language cortex. Pre-operative neurological status was unchanged in 24 patients (70%), worsened in 4 patients (12%) and improved in 6 patients (18%).

CONCLUSIONS

Intra-operative MRI is helpful for navigation as well as to demonstrate the tumour margins to achieve a complete and safe resection of intracranial lesions located in or near eloquent brain areas. It enables an image based functional monitoring of the brain which is critical for motor, sensory or language function. Complications related to the surgical procedure are reduced and the risk of neurological deterioration due to tumour removal and postoperative complications is minimized.

Favorable outcome for children and adolescents with T-cell lymphoblastic lymphoma with an intensive ALL-type therapy without local radiotherapy

In study NHL-BFM 90 we investigated the efficacy of an ALL-type treatment without local radiotherapy for childhood T-cell lymphoblastic lymphoma (T-LBL). In particular, the prognostic impact of the speed of tumor regression was evaluated. From April 1990 to March 1995, 105 evaluable patients, 1.1-16.4 years of age, with T-LBL were enrolled into study NHL-BFM 90. Patients with stage I and II received an 8-drug induction followed by a consolidation including high-dose-methotrexate (MTX) and maintenance therapy up to a total therapy duration of 24 months. Patients with stage III and IV received an additional reinduction and cranial radiotherapy (CRT) (12 Gy for prophylaxis) between consolidation and maintenance. Residual tumor after completion of induction had to be resected. No local RT was applied. Patients received intensified chemotherapy if tumor regression on day 33 of induction was <70% or when vital residual tumor was present after the induction phase. With a median follow-up of 6.41 years, pEFS at 5 years is 91.4% (SE+/-2.7%). 101 patients were evaluable for the speed of tumor response. Two patients received intensified therapy due to <70% tumor regression on day 33. Of 19 patients with tumor residues after induction, 2 relapsed as compared to 4 of 80 patients with complete tumor regression. Our data demonstrate that, with intensive ALL-type chemotherapy but no local radiotherapy, an event-free survival rate of 90% can be achieved in childhood T-LBL. Providing tumor regression within 5 weeks is sufficient, tumor remnants after induction have weak prognostic impact.

Dielectric spectroscopy of Schizosaccharomyces pombe using electrorotation and electroorientation

Two complementary AC electrokinetic techniques electrorotation (ER) and electroorientation (EO) enabled the dielectric characterization of the rod-shaped fission yeast Schizosaccharomyces pombe. The use of microstructured electrodes allowed both ER and EO measurements to be performed over wide ranges of field frequency and medium conductivity. Due to their layered structure, living S. pombe cells exhibited up to three well resolved peaks in their ER spectra and also two distinct orientations, i.e., parallel or perpendicular to the imposed linear field. Heat treatment and enzymatic protoplast isolation led to dramatic changes in the electrokinetic behavior of fission yeast. Application of the theoretical models linking the ER and EO spectra yielded the dielectric parameters of the major structural units of S. pombe cells (cell wall, plasma membrane and cytosol). The dielectric characterization of yeasts has an enormous impact in biotechnology and biomedicine, because electric field pulse techniques (electrofusion and electropermeabilization) are widely used for production of transgenic yeast strains of economic importance. The present study also showed that combined ER and EO measurements can be employed as a powerful diagnostic tool for analyzing changes in yeast structure and physiology upon exposure to various stress conditions.

Neuropeptides: brain messengers of many faces

Neuropeptides 2001, 2nd Joint Meeting of the European Neuropeptide Club and the American Summer Neuropeptide Conference (11th Annual Meeting). 6-11 May 2001 with Satellite Symposium, Israeli-French Symposium, Israel Ministry of Science, Culture and Sport, 6 May 2001, held at Maale Hachmicha and Tel Aviv University, Israel.

Liposomal amphotericin B for prophylaxis of invasive fungal infections in high-risk paediatric patients with chemotherapy-related neutropenia: interim analysis of a prospective study

Invasive fungal infections (IFI) are a major cause of morbidity and mortality in patients with cancer. A retrospective analysis of children with cancer at high risk for IFI treated at Münster University Hospital showed that the incidence (7.4% vs. 1.8%) and lethality (28.1% vs. 0) of documented IFI were lower in patients receiving systemic antifungal prophylaxis with liposomal amphotericin B (l-AmB) in comparison to a historical control group. To determine whether this decline in incidence and lethality was due to antifungal prophylaxis or was produced by advances in diagnostic procedures and early empirical antifungal therapy, a prospective study was initiated. Patients in the prophylaxis arm received thrice-weekly 1 mg kg(-1) body weight l-AmB, whilst patients in the early intervention arm received no prophylaxis. Diagnostic procedures and antifungal therapy for suspected or proven IFI were initiated as clinically indicated for all patients. The primary endpoint of the study was the incidence of IFI. Secondary endpoints were the use of therapeutic doses of l-AmB, the safety of prophylactic l-AmB, and the total consumption of l-AmB for antifungal therapy. The interim analysis after 1 year showed no differences between the two approaches with respect to the incidence of IFI and to safety issues.

Pathobiology of neuropathic pain

This review deals with physiological and biological mechanisms of neuropathic pain, that is, pain induced by injury or disease of the nervous system. Animal models of neuropathic pain mostly use injury to a peripheral nerve, therefore, our focus is on results from nerve injury models. To make sure that the nerve injury models are related to pain, the behavior was assessed of animals following nerve injury, i.e. partial/total nerve transection/ligation or chronic nerve constriction. The following behaviors observed in such animals are considered to indicate pain: (a) autotomy, i.e. self-attack, assessed by counting the number of wounds implied, (b) hyperalgesia, i.e. strong withdrawal responses to a moderate heat stimulus, (c) allodynia, i.e. withdrawal in response to non-noxious tactile or cold stimuli. These behavioral parameters have been exploited to study the pharmacology and modulation of neuropathic pain. Nerve fibers develop abnormal ectopic excitability at or near the site of nerve injury. The mechanisms include unusual distributions of Na(+) channels, as well as abnormal responses to endogenous pain producing substances and cytokines such as tumor necrosis factor alpha (TNF-alpha). Persistent abnormal excitability of sensory nerve endings in a neuroma is considered a mechanism of stump pain after amputation. Any local nerve injury tends to spread to distant parts of the peripheral and central nervous system. This includes erratic mechano-sensitivity along the injured nerve including the cell bodies in the dorsal root ganglion (DRG) as well as ongoing activity in the dorsal horn. The spread of pathophysiology includes upregulation of nitric oxide synthase (NOS) in axotomized neurons, deafferentation hypersensitivity of spinal neurons following afferent cell death, long-term potentiation (LTP) of spinal synaptic transmission and attenuation of central pain inhibitory mechanisms. In particular, the efficacy of opioids at the spinal level is much decreased following nerve injury. Repeated or prolonged noxious stimulation and the persistent abnormal input following nerve injury activate a number of intracellular second messenger systems, implying phosphorylation by protein kinases, particularly protein kinase C (PKC). Intracellular signal cascades result in immediate early gene (IEG) induction which is considered as the overture of a widespread change in protein synthesis, a general basis for nervous system plasticity. Although these processes of increasing nervous system excitability may be considered as a strategy to compensate functional deficits following nerve injury, its by-product is widespread nervous system sensitization resulting in pain and hyperalgesia. An important sequela of nerve injury and other nervous system diseases such as virus attack is apoptosis of neurons in the peripheral and central nervous system. Apoptosis seems to induce neuronal sensitization and loss of inhibitory systems, and these irreversible processes might be in common to nervous system damage by brain trauma or ischemia as well as neuropathic pain. The cellular pathobiology including apoptosis suggests future strategies against neuropathic pain that emphasize preventive aspects.

A new endotoxin adsorber: first clinical application

In an open, uncontrolled pilot study, 5 men and 1 woman with suspected gram-negative sepsis were treated with a new whole-blood endotoxin adsorption system. Lipopolysaccharide (LPS) adsorption was carried out by hemoperfusion over high-affinity polymethacrylate-bound albumin (Fresenius Endotoxin Adsorber EN 500). All patients suffered from endotoxemia (>20 pg/ml LAL) and met at least two systemic inflammatory response syndrome (SIRS) criteria. Four patients suffered from pneumonia due to mechanical ventilation, one from peritonitis, and one from pneumonia and peritonitis. Endotoxin adsorption was very well tolerated, and efficient LPS removal was shown in all patients. Apache II score immediately before immunoadsorption was 23.5 and was 22.3 after the last treatment. All 6 critically ill patients improved substantially and were discharged from the intensive care unit. LPS whole blood immunoadsorption is a promising new method. No side effects have been observed thus far. A large controlled study to prove clinical efficacy in patients with severe sepsis is under way.

Intervertebral disc calcification in childhood--a case report and review of the literature

The authors report the case of a 10-year-old girl with intervertebral disc calcifications from the levels C6/C7 to Th1/Th2, presenting with a herniated calcified intervertebral disc at the C7/Th1 level, causing spinal cord compression with subsequent progressive paresis and sensory loss of her left leg. After anterior cervical discectomy and fusion the neurological deficits completely resolved within 2 weeks. It can be concluded that calcification of an intervertebral disc is a rare syndrome in childhood, causing progressive neurological deficit only in a few reported cases. Although the treatment of choice is conservative, surgery is required in patients who develop progressive neurological deficit.

The risk of haemorrhage associated with early postoperative heparin administration after intracranial surgery

BACKGROUND

To analyse the rate of postoperative haemorrhage during a 4-year period of early postoperative administration (< 24 hours) of fractionated heparin plus compression stockings in a large cohort of patients undergoing intracranial surgery.

METHOD

A total of 1564 patients who underwent intracranial surgery at our institution were included in our study. 1197 of the 1564 patients (77%) had major intracranial surgery (group 1). Group 2 was made up of 367 patients in whom ventriculoperitoneal shunting or external ventriculostomy was performed (minor intracranial procedures). All patients were investigated retrospectively for the occurrence of major postoperative haemorrhage confirmed by CT scanning and requiring surgical evacuation. The protocol for prophylaxis of thrombo-embolic events included early (< 24 hours) postoperative fractionated low-dose heparin (3 x 5000 IE subcutaneously) until discharge plus intra- and postoperative compression stockings.

FINDINGS

Major postoperative haemorrhages were observed in 31 of the 1564 patients (2.0%). In three patients, the haemorrhage occurred on the day of surgery before the administration of heparin. The haemorrhage rate of patients receiving heparin was 1.8% (28/1564). All haemorrhages occurred in patients undergoing major intracranial procedures (group 1; 31/1197; 2.6%). There was no haemorrhage in minor intracranial procedures (group 2; 0/367; 0%).

INTERPRETATION

Although retrospective, this is to date the largest study supporting the concept of postoperative pharmacological thrombo-embolic propylaxis in patients undergoing intracranial surgery. The question as to whether pharmacological prophylaxis is beneficial for a given patient can only be answered by weighing the risk reduction of thrombo-embolic events against the risk increase of postoperative haemorrhage associated with different surgical procedures and heparin protocols.

Effects of the opioid remifentanil on olfactory function in healthy volunteers

The effects of opioids on human subjective olfactory function have rarely been investigated. This is despite the fact that opioid receptors are widely distributed throughout the olfactory systems. Using an established validated test of subjective olfactory function, olfactory threshold, odor discrimination and odor identification performance were tested in 16 healthy volunteers before opioid administration and at steady state after 3 hours remifentanil infusion. Each one man and one women were assigned randomly to one out of eight predefined remifentanil target plasma concentrations: 0, 1.2, 1.8, 2.4, 3, 3.6, 4.8, and 6 ng/ml. In the thirteen subjects that had completed the tests, olfactory thresholds were elevated with increasing remifentanil dose, and this correlated statistically significant with the remifentanil dose. Remifentanil plasma concentrations were linearly related to changes in olfactory thresholds. In contrast, effects of remifentanil on odor discrimination and identification were not statistically significant. However, remifentanil target plasma concentrations were also significantly correlated with the subjects' ratings of tiredness and drowsiness, although only drowsiness was significantly correlated with the differences in odor thresholds. We conclude that opioid administration leads to impaired olfactory function expressed in raised olfactory thresholds. This is compatible with previously reported opioidergic effects at the level of the olfactory bulb.

Differential time courses of skin blood flow and hyperalgesia in the human sunburn reaction following ultraviolet irradiation of the skin

The response of skin to ultraviolet (UV) irradiation is an inflammation with pronounced vasodilation and hyperalgesia. Volunteers underwent UV irradiation of patches of forearm skin 3 cm in diameter. The intensity of the UV irradiation (290-320 nm) ranged between 133 mJ/cm2 and 400 mJ/cm2. Changes in skin blood flow were measured with laser Doppler technique at 3, 6, 9, 12, 24, 30, 36, 48, 60, 72, 96 and 216 h post UV irradiation. The alteration in pain threshold was measured for heat with a Peltier thermode and for pressure with a metal stylus. The effect of repeated topical pre-treatment 4 days prior to UV irradiation with 1.5 g of 0.04% capsaicin containing ointment was also investigated.UV irradiation resulted in a dose-dependent increase of skin blood flow for more than 96 h post-irradiation. There were two peaks of blood flow at 12 h and 36 h. Topical application of capsaicin prior to UV irradiation attenuated blood flow from 30 h to 45 h post UV irradiation. Enhanced blood flow was also present 5 mm outside the irradiated area (flare reaction). The control level of heat pain threshold was 44.5+/-0.7;C in normal skin. Heat pain thresholds were lowered by up to 7.761.2;C in UV-irradiated areas in a dose-dependent fashion. The control level of pressure pain threshold was 15.260.3N. Pressure pain thresholds were lowered by up to 6 N in irradiated areas. Maximal hyperalgesia coincided with the second peak of skin blood flow between 30 h and 60 h post UV irradiation. The effects of topical application of capsaicin suggests an involvement of neuropeptide mechanisms in the late phase of the human sunburn reaction.

White-light frequency comb generation with a diode-pumped Cr:LiSAF laser

We have created a broad spectrum spanning more than an optical octave by launching femtosecond pulses from a battery operated Cr:LiSAF laser into a photonic crystal fiber. Despite the massive broadening in the fiber, the comb structure of the spectrum is preserved, and this frequency comb is perfectly suited for applications in optical frequency metrology.

[Improved treatment results in children with AML: Results of study AML-BFM 93]

BACKGROUND

In the multicenter trial AML-BFM 93 daunorubicin or idarubicin was randomly applied in all patients during induction in combination with cytarabine and etoposide. After induction all patients were stratified to the standard or high risk group. To improve outcome in high risk patients high dose cytarabine and mitoxantrone (HAM) was introduced. The placing of HAM as either the 2nd or 3rd therapy block was randomized to evaluate the efficacy and toxicity accordingly.

PATIENTS AND METHODS

471 children with de novo AML entered the trial AML-BFM 93 (161 standard risk, 310 high risk).

RESULTS

Overall, 387 of 471 (82 %) patients achieved remission, 5-year survival, event free survival (EFS), and disease free survival were 60 % SE 3 %, 51 % SE 2 % and 62 % SE 3 %, respectively. Idarubicin-based induction resulted in a significantly better blast cell reduction in the bone marrow on day 15 (25 of 144=17 % patients with > 5 % blasts compared to 46 of 149=31 % patients after daunorubicin, pchi(2)=0.01). This was, however, mainly seen in high risk patients treated with idarubicin (19 % vs. 38 %, pchi(2)=0.007). Cardiotoxicity, WHO grade 1 - 3 shortening fraction reduction after induction occurred in 6 % patients in both arms. In the total group of patients probabilities of five years event-free survival and disease-free survival were similar for patients treated with daunorubicin or idarubicin. However, in patients presenting with more than 5 % blasts on day 15 there was a trend for a better outcome after treatment with idarubicin (p logrank 0.06). Outcome in high risk patients was superior in study 93 compared to study 87 (remission rate and 5-year pEFS in study AML-BFM 93 vs. study 87: 78 % vs. 68 %, p=0.007, and 44 % vs. 31 %, p logrank=0.01). The placing of HAM as the 2nd or 3rd therapy block was of minor importance. However, patients who received the daunorubicin treatment during induction benefited from early HAM.

CONCLUSION

Compared to study AML-BFM 87 treatment results in study AML 93 improved significantly in high risk patients. This can partly be contributed to the better response on day 15 after idarubicin induction but is mainly due to the introduction of HAM.

Clinical outcome of patients with childhood acute lymphoblastic leukaemia and an initial leukaemic blood blast count of less than 1000 per microliter

BACKGROUND

One of the strongest predictive factors for therapy outcome in childhood acute lymphoblastic leukaemia (ALL), treated according to ALL-BFM protocols, is the response to initial prednisone treatment. Prednisone response is characterized by the peripheral leukaemic blast count. The threshold value for the characterisation as good or poor prednisone response is 1000 blasts/microliter on day eight of initial prednisone treatment. It is frequently being discussed, whether patients with ALL that initially present with < 1000 blasts/microliter and still show < 1000 blasts/microliter by day eight of treatment, have the same therapy outcome as prednisone good-responders with initially >/= 1000 blasts/microliter.

PATIENTS AND METHODS

We evaluated all patients included in the ALL-BFM 90 study showing good prednisone response. This group included 660 patients presenting with < 1000 blasts/microliter at diagnosis. We compared these patients with the prednisone good-responders that initially presented with >/= 1000 blasts/microliter. In addition we analysed all patients who showed an increasing blast count within the threshold of 1000 blasts/microliter by day eight of treatment.

RESULTS

Children presenting with ALL and < 1000 blasts/microliter at diagnosis showed a small but significantly better outcome than prednisone good-responders with initially >/= 1000 blasts/microliter (5 year pEFS 0.86 vs. 0.81, P value 0.0064). If analyzed by treatment group, no significant differences were found. Patients with < 1000 blasts/microliter on day eight of treatment but increasing blast count from diagnosis until day eight did not perform worse.

CONCLUSION

The prognostic value of the prednisone response is not restricted to childhood ALL patients presenting with >/= 1000 blasts/microliter at diagnosis, but retains its strength as a strong predictor of treatment outcome also in patients with < 1000 blasts/microliter at diagnosis.

Short-pulse B-non-Hodgkin lymphoma-type chemotherapy is efficacious treatment for pediatric anaplastic large cell lymphoma: a report of the Berlin-Frankfurt-Münster Group Trial NHL-BFM 90

Anaplastic large-cell lymphoma (ALCL) accounts for approximately 10% of pediatric non-Hodgkin lymphoma (NHL). Previous experience from NHL-Berlin-Frankfurt-Münster (BFM) trials indicated that the short-pulse B-NHL-type treatment strategy may also be efficacious for ALCL. The purpose of this study was to test the efficacy of this protocol for treatment of childhood ALCL in a large prospective multicenter trial and to define risk factors. From April 1990 to March 1995, 89 patients younger than 18 years of age with newly diagnosed ALCL were enrolled in trial NHL-BFM 90. Immunophenotype was T-cell in 40 patients, B-cell in 5, null in 31, and not determined in 13. Stages were as follows: I, n = 8; II, n = 20; III, n = 55; IV, n = 6. Extranodal manifestations were as follows: mediastinum, n = 28; lung, n = 13; skin, n = 16; soft tissue, n = 13; bone, n = 14; central nervous system, n = 1; bone marrow, n = 5. After a cytoreductive prephase, treatment was stratified into 3 branches: patients in K1 (stage I and II resected) received three 5-day courses (methotrexate [MTX] 0.5 g/m(2), dexamethasone, oxazaphorins, etoposide, cytarabine, doxorubicin, and intrathecal therapy); patients in K2 (stage II nonresected and stage III) received 6 courses; patients in K3 (stage IV or multifocal bone disease) received 6 intensified courses including MTX 5 g/m(2), high-dose cytarabine/etoposide. The Kaplan-Meier estimate for a 5-year event-free survival was 76% +/- 5% (median follow-up, 5.6 years) for all patients and 100%, 73% +/- 6%, and 79% +/- 11% for K1, K2, and K3, respectively. Events were as follows: progression during therapy, n = 2; progression or relapse after therapy, n = 20; second malignancy, n = 1. It was concluded that short-pulse chemotherapy, stratified according to stage, is effective treatment for pediatric ALCL. B symptoms were associated with increased risk of failure. (Blood. 2001;97:3699-3706)

Improved treatment results in high-risk pediatric acute myeloid leukemia patients after intensification with high-dose cytarabine and mitoxantrone: results of Study Acute Myeloid Leukemia-Berlin-Frankfurt-Münster 93

PURPOSE

To improve outcome in high-risk patients, high-dose cytarabine and mitoxantrone (HAM) was introduced into the treatment of children with acute myelogenous leukemia (AML) in study AML-BFM 93. Patients were randomized to HAM as either the second or third therapy block, for the purpose of evaluation of efficacy and toxicity.

PATIENTS AND METHODS

A total of 471 children with de novo AML were entered onto the trial; 161 were at standard risk and 310 were at high risk. After the randomized induction (daunorubicin v idarubicin), further therapy, with the exception of HAM, was identical in the two risk groups and also comparable to that in study Acute Myeloid Leukemia-Berlin-Frankfurt-Münster (AML-BFM) 87.

RESULTS

Overall, 387 (82%) of 471 patients achieved complete remission, and 5-year survival, event-free survival (EFS), and disease-free survival rates were 60%, 51%, and 62%, respectively. Idarubicin induction resulted in a significantly better blast cell reduction in the bone marrow on day 15. Estimated survival and probability of EFS were superior in study AML-BFM 93 compared with study AML-BFM 87 (P =.01, log-rank test). This improvement, however, was restricted to the 310 high-risk patients (remission rate and probability of 5-year EFS in study AML-BFM 93 v study AML-BFM 87: 78% v 68%, P =.007; and 44% v 31%, P =.01, log-rank test). Probability of 5-year EFS among standard-risk patients in study AML-BFM 93 was similar to that in study AML-BFM 87 (65% v 63%, P = not significant). Whether HAM was placed as the second or third therapy block was of minor importance. However, patients who received the less intensive daunorubicin treatment during induction benefited from early HAM.

CONCLUSION

Improved treatment results in children with high-risk AML in study AML-BFM 93 must be attributed mainly to the introduction of HAM.

Rivet-like titanium clamp fixation of cranial bone flaps during open magnetic resonance-guided neurosurgery

A new implant technique for bone flap fixation after magnetic resonance image-guided neurosurgical procedures in the first vertical open 0.5T MRI scanner is described. Between May 1998 and December 1998 cranial bone flap refixation was performed in 20 patients using rivet-like titanium cranial bone flap fixation clamps. In all cases, a safe and solid refixation of the bone flap was achieved. Intraoperative and postoperative MRI quality was not influenced. Rivet-like titanium clamp bone fixation is a safe procedure which can be easily performed under the special circumstances during neurosurgical operations with interventional MRI.

Inhibition of endothelin-converting enzyme activity in the rabbit basilar artery

OBJECTIVE

Endothelin (ET)-1 may be involved in the regulation of cerebrovascular resistance under pathological conditions, most notably during the development of vasospasm after subarachnoid hemorrhage. Blocking ET-converting enzyme activity may be a promising approach to the prevention of cerebral vasospasm after subarachnoid hemorrhage.

METHODS

In this study, the effects of several putative ET-converting enzyme inhibitors were investigated after intracisternal application in rabbits, to inhibit basilar artery contractions induced by big ET-1 (2 x 10(-6) mol/L).

RESULTS

In the group pretreated with [D-Val22]big ET-1[16-38] (2 x 10(-5) mol/L) (n = 8), the angiographically measured diameter of the basilar artery changed from 0.63 +/- 0.12 mm to 0.66 +/- 0.12 mm. In the control group (n = 8), the diameter of the basilar artery decreased from 0.71 +/- 0.13 mm to 0.57 +/- 0.15 mm. These results corresponded to an increase in vessel diameter of 5 +/- 10% in the treatment group and a decrease in vessel diameter of 20 +/- 16% in the control group (P = 0.014). In the group pretreated with captopril (2 x 10(-4) mol/L) (n = 8), the angiographically measured diameter of the basilar artery changed from 0.64 +/- 0.11 mm to 0.71 +/- 0.10 mm. These results corresponded to an increase in vessel diameter of 14 +/- 19% in the treatment group, compared with a decrease in vessel diameter of 20 +/- 16% in the control group (P = 0.014).

CONCLUSION

These results demonstrate that [D-Val22]big ET-1[16-38] and captopril act as highly potent ET-converting enzyme inhibitors, affecting big ET-1-induced contraction of the rabbit basilar artery.

[Management of patients with chronic pain syndromes--deficits and perspectives]

Just little more than 10 years ago, pain was still considered a neglected aspect of medicine. Since that time, however, significant progress has been made in this field. The magnitude of the problem is evident from the fact that some 5 million Germans suffer from chronic pain, 600,000 of whom are considered to be particularly affected. It is with regard to these pain patients that the term "chronic pain disorder" has been coined. The mechanisms of progressive pain chronicity form one of the central topics in pain research. The plasticity of neuronal pain systems seems to be particularly relevant in this area. Increasingly, interdisciplinary pain management is available to patients with chronic pain disorder, demonstrating both the possibility of improvement for the chronic pain patient and the reduction in costs for the health care system. The number of such pain treatment/management facilities still needs to be expanded because "divinum est sedare dolorem"--it is divine to alleviate pain (Galen of Pergamon).