Active Participation, Mind-Body Stabilization, and Coping Strategies with Integrative Medicine in Breast Cancer Patients

PURPOSE

Increasing numbers of breast cancer survivors have led to a growing demand for integrative medicine. When patients have completed treatments associated with severe side effects, attention turns to reducing psychological symptoms, coping behavior, and self-care. The aim of this study was to assess patient-reported benefits in relation to active participation, mind-body stabilization, and coping strategies in breast cancer patients receiving integrative medicine.

METHODS

In a cross-sectional study, health counseling and treatment provided by a standardized integrative medicine consultancy service at the University Breast Center of Franconia were evaluated in 75 breast cancer patients over a 15-month period. At the baseline, the patients answered a questionnaire on their medical history, symptoms, and the treatment goals they were hoping to achieve with integrative medicine. Patient-reported outcomes relative to active participation, mind-body stabilization, and coping strategies were analyzed.

RESULTS

A large majority of the patients had previous experience with integrative medicine (91%). Most reported that they achieved their treatment goals with integrative medicine. Ninety-one percent achieved active participation in cancer treatment, 90% mind-body stabilization, and 79% improvement in coping strategies. Besides active participation, which was greatest in patients with stable disease, the success of integrative therapy was independent of age, concomitant diseases, previous integrative medicine experience, treatment state, and systemic cancer therapy.

CONCLUSION

Breast cancer patients benefit from the counseling and treatment provided with integrative medicine in mind-body stabilization and coping with cancer. Active participation in cancer treatment is important for the patients. Integrative treatment services should form part of routine patient care.

Diagnostic Accuracy of Breast Medical Tactile Examiners (MTEs): A Prospective Pilot Study

Background

The usefulness of clinical breast examination (CBE) in general and in breast cancer screening programs has been a matter of debate. This study investigated whether adding vision-impaired medical tactile examiners (MTEs) improves the predictiveness of CBE for suspicious lesions and analyzed the feasibility and acceptability of this approach.

Methods

The prospective study included 104 patients. Physicians and MTEs performed CBEs, and mammography and ultrasound results were used as the gold standard. Sensitivity and specificity were calculated and logistic regression models were used to compare the predictive value of CBE by physicians alone, MTEs alone, and physicians and MTEs combined.

Results

For CBEs by physicians alone, MTEs alone, and both combined, sensitivity was 71, 82, and 89% and specificity was 55, 45, and 35%, respectively. Using adjusted logistic regression models, the validated areas under the curve were 0.685, 0.692, and 0.710 (median bootstrapped p value (DeLong) = 0.381).

Conclusion

The predictive value for a suspicious breast lesion in CBEs performed by MTEs in patients without prior surgery was similar to that of physician-conducted CBEs. Including MTEs in the CBE procedure in breast units thus appears feasible and could be a way of utilizing their skills.

Initial clinical results with a fusion prototype for mammography and three-dimensional ultrasound with a standard mammography system and a standard ultrasound probe

BACKGROUND

Combinations *Equal contributors. of different imaging techniques in fusion devices appear to be associated with improvements in diagnostic assessment.

PURPOSE

The aim of this study was to test the feasibility of using an automated standard three-dimensional (3D) ultrasound (US) device fused with standard mammography for the first time in breast cancer patients.

MATERIAL AND METHODS

Digital mammograms and 3D automated US images were obtained in 23 patients with highly suspicious breast lesions. A recently developed fusion machine consisting of an ABVS 3D US transducer from an Acuson S2000 machine and a conventional Mammomat Inspiration device (both Siemens Healthcare GmbH, Erlangen, Germany) were used for the purpose. The feasibility of the examinations, imaging coverage, and patients' experience of the procedure were examined.

RESULTS

In 15 out of 19 patients, the region of interest (ROI) with the tumor marked in the mammogram was visible on US. The examination was experienced positively by the patients, with no unexpected pain or injury. The examination was time-saving and well tolerated.

CONCLUSION

In conclusion, we have shown initial clinical feasibility of an US/radiography fusion prototype with good localization and evaluation of the ROIs. The combined examination was well tolerated. The simultaneous evaluation with mammography and US imaging may be able to improve detection and reduce examiner-related variability.

Supportive Infusions in Integrative Breast and Gynecological Oncology - Report on Patients' Satisfaction and Self-reported Effects and Side Effects

Background During cancer therapy, many patients suffer from malnutrition or vitamin deficiency. Treatment for nutrition-related deficiencies should therefore include nutritional therapy and possibly oral or intravenous substitution of micronutrients. Little information exists on multinutrient infusion therapies. The aim of this study was to develop standardized infusion protocols for integrative medicine infusions with micronutrients (IMed infusions) and to report on side effects of the treatment and patientsʼ satisfaction with it.

Methods For the IMed consultancy service, four special formulas for intravenous use were developed in cooperation with the pharmacy at Erlangen University Hospital. A retrospective cross-sectional study was conducted between October 2015 and January 2018 in which 45 patients with gynecological or breast cancer (BC) and IMed infusion therapy were included. Follow-up data were obtained from 20 patients using a standardized questionnaire on IMed infusions.

Results A total of 280 IMed infusions were administered in the study period. The majority of the patients received an IMed regeneration infusion (78%). The majority of the patients had BC and were receiving chemotherapy. Most patients reported a high or very high level of satisfaction with the organization (60%), general treatment (65%) and counseling (85%). Subjective improvement in their disease-related and therapy-induced symptoms, such as fatigue, polyneuropathy and physical efficiency, was reported by 70% of the patients, while 75% reported a subjective increase in quality of life. Side effects were rare and minor.

Conclusions Therapy with IMed infusions in women with BC or gynecological cancer requires the same standards set for drug therapy. Although vitamins represent dietary supplements, appropriate assessment of the patientʼs medical history is needed and patients must receive appropriate information. For this purpose, standardized processes, as in the context of an IMed consultancy service, are helpful.

Self-reported Improvement in Side Effects and Quality of Life With Integrative Medicine in Breast Cancer Patients

Purpose. Although the demand from patients for integrative medicine is increasing, complementary medicine services are still quite heterogeneous and have not been incorporated into clinical routine. The aim of this study was to systematically evaluate improvements in side effects and quality of life associated with a hospital-based integrative medicine program in the modern breast cancer patient care setting. Methods. In a cross-sectional study, integrative health counseling and treatment were evaluated in women with breast cancer. Over a 15-month period, data for 75 patients from an integrative medicine consultancy service with standardized operating procedures were collected at the University Breast Center for Franconia. At baseline, the patients answered a questionnaire on their medical history, symptoms, and the treatment goals they were hoping to achieve with integrative medicine. In the follow-up, patient-reported outcomes related to side effects of conventional cancer treatment and patients’ quality of life were analyzed. Results. Among 60 patients with the therapy goal of reducing the side effects of conventional treatment, 46 (76.7%) were successful. Among 57 patients hoping to improve disease-related quality of life, 46 (82%) reported success. Whereas patients with metastatic disease achieved a reduction in the side effects of conventional therapy, quality-of-life improvements were predominantly achieved by patients with a good treatment prognosis. Conclusions. Breast cancer patients benefit from the counseling and treatment provided with integrative medicine in all phases of tumor disease. Integrative treatment services should be included as part of patient care in clinical routine work to offer patients the maximum quality of care and safety with complementary therapies.

TILGen: A Program to Investigate Immune Targets in Breast Cancer Patients - First Results on the Influence of Tumor-Infiltrating Lymphocytes

BACKGROUND

Despite advancements in the treatment of primary and metastatic breast cancer, many patients lack a durable response to these treatments. Patients with triple-negative breast cancer (TNBC) and human epidermal growth factor receptor 2(HER2)-positive breast cancer who do not have a pathological complete response (pCR) after neoadjuvant chemotherapy (NACT) have a very poor prognosis. Tumor-infiltrating lymphocytes (TILs) have been identified as a predictive marker for pCR after NACT in TNBC and HER2-positive breast cancer. These patient populations could also be suitable for novel treatment strategies including neoepitope-based therapies. This work analyses the effect of TILs on the pCR in neoadjuvantly treated patients in the TILGen study and presents the procedures aimed at establishing neoepitope-based therapies in this study.

METHODS

Neoadjuvantly treated HER2-positive and TNBC patients were eligible for the presented analysis concerning the association between TILs and pCR. A total of 146 patients could be identified within the TILGen study. TILs were evaluated as percentage of stromal tumor tissue in core biopsies at primary diagnosis. The phenotype 'lymphocyte-predominant breast cancer' (LPBC) was associated with pCR by logistic regression adjusted for estrogen receptor status, progesterone receptor status, HER2 status, age at diagnosis, and grading.

RESULTS

LPBC was seen in 24 (16.4%) patients. In this patient group, 66.7% achieved a pCR, while the pCR rate was 32.8% in patients with a low TIL count. The adjusted odds ratio was 6.60 (95% confidence interval 2.02-21.56; p < 0.01).

CONCLUSION

TILs are a strong predictor of pCR in TNBC and HER2-positive breast cancer patients. Implications for the use of this information including the effect on prognosis might help to identify patients most likely to benefit from a neoepitope-based therapy approach.

Implementation and Feasibility of Electronic Patient-Reported Outcome (ePRO) Data Entry in the PRAEGNANT Real-Time Advanced and Metastatic Breast Cancer Registry

PURPOSE

Patient-reported outcomes (PROs) have been incorporated into clinical trials for many symptoms and medical conditions. A transition from paper-based capture of PROs to electronic PROs (ePROs) has recently started. This study reports on the feasibility of ePRO assessment in a prospective registry including molecular data for patients with advanced breast cancer.

METHODS

As part of the PRAEGNANT network, patients were invited by clinical trial staff, physicians, and nurses to complete three standardized Internet-based questionnaires (EQ 5D 5 L, CES-D and IPAQ). Feasibility was assessed by the staff members who assigned the user accounts by the patients. The completeness of the questionnaires was also assessed.

RESULTS

Fifteen of 17 patients who were asked agreed to participate to complete the PRO questionnaires (EQ-5D-5L and CES-D). However, the IPAQ (physical activity) questionnaire was only validly completed by 9 patients. Feasibility was ranked better by the physicians and dedicated clinical trial staff than by the nursing staff.

CONCLUSIONS

Incorporating ePRO questionnaires into an advanced breast cancer registry is feasible, and no major hurdles were reported. Involving stakeholders from the start, the application is tailored to the capacities and abilities of both patients and clinical staff. The patients' compliance was better with some questionnaires, but others may present difficulties.

A Standard Mammography Unit - Standard 3D Ultrasound Probe Fusion Prototype: First Results

AIM

The combination of different imaging modalities through the use of fusion devices promises significant diagnostic improvement for breast pathology. The aim of this study was to evaluate image quality and clinical feasibility of a prototype fusion device (fusion prototype) constructed from a standard tomosynthesis mammography unit and a standard 3D ultrasound probe using a new method of breast compression.

MATERIALS AND METHODS

Imaging was performed on 5 mastectomy specimens from patients with confirmed DCIS or invasive carcinoma (BI-RADS ^™ 6). For the preclinical fusion prototype an ABVS system ultrasound probe from an Acuson S2000 was integrated into a MAMMOMAT Inspiration (both Siemens Healthcare Ltd) and, with the aid of a newly developed compression plate, digital mammogram and automated 3D ultrasound images were obtained.

RESULTS

The quality of digital mammogram images produced by the fusion prototype was comparable to those produced using conventional compression. The newly developed compression plate did not influence the applied x-ray dose. The method was not more labour intensive or time-consuming than conventional mammography. From the technical perspective, fusion of the two modalities was achievable.

CONCLUSION

In this study, using only a few mastectomy specimens, the fusion of an automated 3D ultrasound machine with a standard mammography unit delivered images of comparable quality to conventional mammography. The device allows simultaneous ultrasound - the second important imaging modality in complementary breast diagnostics - without increasing examination time or requiring additional staff.

17beta-Estradiol reduces cortical lesion size in the glutamate excitotoxicity model by enhancing extracellular lactate: a new neuroprotective pathway

Estrogens play an important role in neuronal function and in protecting neurones in the cerebral cortex against pathological conditions. An in vivo model of glutamate excitotoxicity in which glutamate is applied to the cortex of rats through a microdialysis probe has been used to investigate the neuroprotective processes initiated by 17beta-estradiol. Rats were pre-treated with 17beta-estradiol (i.v.) before local application of 100 mM glutamate into the cortex through a microdialysis probe. Pre-treatment with 17beta-estradiol significantly reduced the size of the glutamate-induced cortical lesion. In the cortical microdialysates collected from the probe, a peak of lactate was observed immediately after glutamate application. After 17beta-estradiol pre-treatment this peak of lactate was significantly higher with estradiol than without 120 min after glutamate application, reaching 700% basal level at the end of measurement. The level of extracellular glucose was markedly decreased with and without 17beta-estradiol pre-treatment. Local blockage of neuronal lactate transporters with alpha-cyano-4-hydroxycinnamate (4-CIN) completely abolished the neuroprotective effect of 17beta-estradiol and induced a larger cortical lesion. An accumulation of extracellular lactate was observed after inhibition of the lactate transporters suggesting that transport of lactate into neurones is necessary for the neuroprotective effect of 17beta-estradiol. The anti-estrogen tamoxifen also abolished the neuroprotective effect of 17beta-estradiol on the lesion size and inhibited the production of lactate. These results suggest a new neuroprotective mechanism of 17beta-estradiol by activating glutamate-stimulated lactate production, which is estrogen receptor-dependent.

Microdialytical monitoring of uric and ascorbic acids in the brains of patients after severe brain injury and during neurovascular surgery

OBJECTIVES

Microdialysis has been extensively used to monitor brain metabolism in the extracellular fluid of patients with severe head injury, to detect the onset of secondary ischaemic damage. The aim was to investigate whether concentrations of uric and ascorbic acids were altered in such patients. Both these compounds play a part in free radical metabolism, which is accelerated after ischaemia and brain injury.

METHODS

Patients with aneurysm or bypass operations were monitored intraoperatively to assess concentrations in minimally disturbed tissue. Afterwards, 13 patients with severe head trauma were monitored for up to 13 days in the intensive care unit.

RESULTS

Intraoperatively, concentrations of both ascorbic and uric acids were significantly higher in the bypass group than in patients with aneurysm, which might be attributed to chronic ischaemic conditions caused by the unilateral occlusion of the carotid artery. In the patients with trauma, mean values of uric acid, varying between 6 microM and 180 microM, did not correlate with type of injury (contusion or diffuse) or duration of monitoring time. Patients who died had significantly higher concentrations of uric acid than those with a good outcome. Ascorbic acid could be detected only intermittently, probably due to technical problems. Concentrations of these two compounds could not be correlated with clinical findings during the course of monitoring.

CONCLUSIONS

Although uric and ascorbic acids are influenced by ischaemic conditions-for example, in bypass patients, neither compound is suitable for monitoring for free radical activity after severe head injury. Patients with a bad outcome tended to have higher concentrations of uric acid.

Extracellular levels of glucose and lactate measured by quantitative microdialysis in the human brain

The aim of this study was to use quantitative microdialysis to estimate the true extracellular concentrations of glucose and lactate in minimally disturbed human brain. These values are important as criteria for microdialytical monitoring in critical care patients and for determining therapy. Microdialysis procedures were carried out during tumor operations, the probe being inserted distant from the site of manipulation in minimally disturbed tissue. Two methods were used: 1. The zero net flux method of Lönnroth. 2. The low flow method (10 mm membrane length, flow rate 0.3 microliter min-1, high in vivo recovery). Both methods gave similar values of about 2000 microM for lactate and slightly less for glucose (1700 microM). Glucose levels correspond with those measured by other methods in humans, allowing for the fact that our patients were anesthetised. Extracellular glucose levels were positively correlated with blood glucose values measured before the operation, and with extracellular lactate. Results confirm that extracellular glucose is zero when blood glucose is about 2 mM.

A four lumen screwing device for multiparametric brain monitoring

We describe multiparametric monitoring in severe head trauma using a new screwing device. Our aim was to create a screw which would make the implantation of the probes and thus multiparametric monitoring easier. The new screw allows us to implant 3 probes (microdialysis, Paratrend and an intracranial pressure device) through one burr hole. The screw has four channels, the fourth being for ventricular drainage. We monitored 13 patients with severe head trauma (GCS = 3-8) for up to 7 days. Brain tissue pO2, pCO2, pH, and temperature were measured on-line with the Paratrend 7 machine. The microdialytic parameters glucose, lactate, pyruvate and glutamate were determined semi on-line with a CMA 600 enzymatic analyser. There were no complications in any of the patients that could be ascribed to the screw.

Extracellular glutamate and other metabolites in and around RG2 rat glioma: an intracerebral microdialysis study

The current study determined the extracellular content of glutamate, 10 additional amino acids, lactate, glucose and some antioxidants in a rodent model of malignant glioma, its peritumoral space and the adjacent cortex. RG2 tumors were induced in the right frontal cortex of Fischer-344 rats (n = 10) by a standardized procedure to obtain a maximum sagittal tumor width of 3-4 mm diameter. After confirmation of tumor growth and localization by contrast enhanced MRI three microdialysis probes were implanted simultaneously in the cortex: at the tumor implantation site (tumor), 2 mm caudally, brain around tumor (BAT) and 4 mm caudally (cortex) to the site of implantation. Dialysate concentrations of glutamate were increased 3.9-fold in tumor and 2-fold in BAT compared with cortex. Glycine was elevated 11.4-fold in tumor and 2.6-fold in BAT. Lactate was increased 1.7-fold in tumor, 1.2-fold in BAT. Levels of glucose, ascorbic acid and uric acid were not significantly different in tumor, BAT and cortex. The increased dialysate levels of glutamate and glycine in the peritumoral space may contribute to impaired neuronal function and epileptiform activity associated with this tumor type in humans.

Chronic effects of an aminosteroid on microdialytically measured parameters after experimental middle cerebral artery occlusion in the rat

The effects of the neuroprotective aminosteroid U74006F (tirilazad mesylate, Freedox) were monitored microdialytically in rat cortex during three 4h periods beginning immediately, 25h and 49h after permanent middle cerebral artery occlusion. Either U74006F or vehicle only was administered 15 min, 2h, 6h, 12h and 24h after operation. The dialysate was analysed for on-line pH, ascorbic acid, uric acid, glucose and lactate. The efficacy of post-ischaemic treatment was shown by: a) lesion volume 53h after operation was significantly smaller in U74006F-treated animals; b) microdialytic findings were very similar to those found previously with pre-ischaemic drug application (reduction in release of ascorbic acid, uric acid and lactate, increased pH); c) an effect of U74006F on lactate release could still be seen on days 2 and 3; and d) increases in uric acid on days 2 and 3, possibly reflecting delayed cell death, were smaller in aminosteroid treated animals.

[Intraoperative and postoperative microdialysis measurement of the human heart--feasibility and initial results]

STUDY OBJECTIVE

Microdialysis measurements of human cardiac metabolism during and after cardiac operations have not been published up to now. The goal of this study was to evaluate feasibility of the method in a clinical setting and to interpret first results.

PATIENTS AND METHODS

In 5 patients microdialysis measurements were made in regular intervals during aortocoronary bypass surgery. Analysis of dialysate was done by high performance liquid chromatography or enzymatic fluorometry. In the last 2 patients measurements were also taken during the postoperative course up to the time of extubation.

RESULTS

During aortic cross clamping a mean 7-fold rise of the radical scavenger glutathione was observed (range 0.9-15.4; p = 0.06). During reperfusion the glucose/lactate(Glc/Lac)-rate rose from 0.4 to 3.1 (p = 0.02). Concentrations of ascorbic acid, cysteine and uric acid remained neutral or showed no regular changes. In the 2 patients who were also observed postoperatively, lactate rose significantly at 190 min and 340 min postoperatively (decrease in Glc/Lac-ratio from 2.5 to 0.4 and 2.0 to 0.4 respectively).

CONCLUSIONS

Microdialytic measurements of metabolic parameters can be performed on the human heart in a clinical setting. So far no complications have been observed and the microdialysis probe can be installed in such a fashion, that it can be easily removed transcutaneously during the postoperative course. Substances that are important in ischemia and reperfusion can be measured and their concentrations show changes that are not just artefacts. Postoperatively, metabolic alterations may be observed in the myocardial septum that are not recordable with conventional techniques (i.e., pressure measurements, cardiac output, ECG).

Microdialytic monitoring during cerebrovascular surgery

Using microdialysis, levels of metabolites in the extracellular fluid of the cerebral cortex were monitored during neurovascular surgery (9 aneurysm and 5 extra-intracranial bypass operations). Our aim was to use microdialysis to detect any local ischemia which might be caused by brain retraction or temporary clipping. Parameters were therefore quantified whose levels in the dialysate are known to be influenced by ischemia (on-line pH, ascorbic acid, uric acid, glutathione, cysteine, glucose, lactate, glucose:lactate ratio). In the aneurysm series, on-line pH fell after introduction of the retractor, and in the majority of cases the other parameters also showed changes in accordance with ischemic conditions in the region of the probe. These changes disappeared at the end of retraction, or sometimes even before. During the bypass operations, there were no marked changes in on-line pH or in any of the measured parameters. However, in some of these patients values for the glucose:lactate ratio, ascorbic acid and uric acid lay outside the suggested basal levels for minimally disturbed cortex, indicating possible changes in metabolism caused by inadequate perfusion (carotid artery occlusion). We conclude that microdialysis is a sensitive method of detecting intraoperative changes in cerebral metabolism.

Cerebral microdialysis as a diagnostic tool in acute brain injury

In the past 10 years, the management of brain injury has shown several advances. Besides new diagnostic tools many new tentative approaches have been investigated, such as jugular bulb measurement of oxygen and lactate differences and near-infrared spectroscopy. The latest tool is microdialysis, which uses a probe as an interface to the brain. This method uses internally perfused semi-permeable membrane probes, which allow neurochemical water-soluble substances to be collected outside the brain for further analysis. Since the late 1980s the first results of microdialysis in neurointensive care show that chemical substances such as lactate, glucose, amino acids, metabolites of several biochemical mechanisms and electrolytes are measurable. This heterogeneous approach now waits for validation for clinical use and for the most challenging aspect, the clinical interpretation and use to improve therapy. The aim of this review is to describe the state of the art of this new technique, including our own experiences and concepts.

Microdialytic monitoring during a cardiovascular operation

In an aorta-coronary bypass operation, the heart is excluded from the circulation for many minutes, leading to ischemia. During this time the heart is cooled in order to mitigate damage. Microdialysis has been shown to be very suitable for detecting ischaemic changes e.g. in brain. We therefore used this method to study the time courses of several neurochemical parameters which have been shown to indicate ischaemia in animal models (ascorbic acid, glutathione, cysteine, uric acid, glucose, lactate and pH), during such a bypass operation. Three patients were investigated, the microdialysis probe being inserted into the interventricular septum of the heart. Our results show that microdialysis is technically feasible in the human heart in a clinical setting, although the operation becomes more demanding for the surgeon. All the above-mentioned parameters could be detected in the heart muscle. Some of them showed changes characteristic of ischaemia, and the effects of cooling on the metabolism could also be noted. Long term measurements are planned to enable delayed damage to be disclosed.

A concept for the introduction of cerebral microdialysis in neurointensive care

Before microdialysis (MD) can be introduced into the clinic as an improved method of cerebral monitoring, certain ethical, methodological and clinical factors must be considered. Access to the brain for probe insertion is offered by craniotomy or by routine intracranial pressure (ICP) monitoring and the additional lesion is minimal. Care must be taken that the two devices do not interfere with each other. In contrast to ICP monitoring, MD provides information about multiple aspects of brain metabolism. We can monitor either still intact tissue to prevent additional damage, or injured brain to decide on and control therapies. The parameters used must reflect pathological changes an early stage, and the analysis should be available on-line or immediately after sample collection. The effects off factors such as tube length and flow rate on the behaviour of the chosen parameters (in our case on-line pH, radical scavengers and uric acid) in the MD set-up must be investigated in vitro and in animal models before use in the clinic. The range of non-pathological values of parameters of interest in human brain should be known For this purpose we took measurements during an extracranial-intracranial bypass operation, and were able to compare values with those in a severely damaged brain. The mutual chronology of parameter changes and clinical events must be clear. Future aspects include the use of low-flow methods offering nearly 100% recovery, improved analytical methods, and combination of MD with other monitoring methods to obtain more exact information.

A new screwing device for fixing a microdialysis probe in critical care patients

We describe a new, easy method which extends the use of clinical microdialysis to neurotrauma patients who primarily do not need a decompressing surgical intervention. In all head trauma patients in whom a Camino ICP-monitor is indicated a second hole (2 mm in diameter) is made, and the MD probe is fixed using the new screwing device. Before clinical use the system was tested during postmortem, confirming correct cortical placement of the probe in almost all cases. Two case reports are presented including their metabolic values. An extension to patients with non-traumatic brain disorders might be a future aspect.

Microdialytic monitoring of the cortex during neurovascular surgery

Using microdialysis combined with suitable analytical methods, levels of metabolites in the extracellular fluid of the cerebral cortex were monitored during neurovascular surgery (9 aneurysm and 5 bypass operations). Our aim was to use microdialysis to detect any local ischaemia which could be caused by brain retraction, temporary clipping and dissecting manoevres. For this purpose, parameters were quantified whose levels in the dialysate are known to be influenced by ischaemia (on-line pH, ascorbic acid, uric acid, glutathione, cysteine, glucose, lactate). In the aneurysm series, the on-line pH fell after introduction of the retractor, and rose after removal: also, in many cases, levels of ascorbic acid, glutathione and lactate increased and glucose decreased. These changes are all in accordance with ischaemic conditions in the region of the probe; they disappeared at the end of retraction, or sometimes even before. During the bypass operations, there were no marked changes in on-line pH or in any of the measured parameters. However, in 2 of these patients ascorbic acid, uric acid and glucose levels were very high during the whole measurement, indicating possible changes in metabolism caused by inadequate perfusion (carotid artery stenosis). We conclude that microdialysis is a sensitive method of detecting intraoperative changes in cerebral metabolism.

Application of glutamate in the cortex of rats: a microdialysis study

Glutamate, a major neurotransmitter in the brain, is also involved in pathophysiological processes resulting in secondary lesions following ischaemia or trauma. In the present study we investigated the relationship between glutamate excitotoxicity free radical induction (indicated by ascorbic acid level) and glucose-lactate metabolism. Monosodium glutamate was applied through microdialysis probes (500 mM in perfusate) into the cortex of rats for 30 minutes and ascorbic acid (ASC), glucose (GLUC) and lactate (LAC) were measured in dialysates. Glutamate produced a cortical lesion with an average volume of 12.7 +/- 1.4 mm3. Analysis of dialysates revealed a significant increase of ASC (325 +/- 52% of baseline) and LAC (677 +/- 86%) in the core lesion. In the lesion periphery a non-significant and short-lasting elevation was measured for both parameters with a second microdialysis probe (about 1.3 mm frontally to the first probe). A concomitant decrease of GLUC was found in both probes, reaching 29 +/- 8% and 60 +/- 7% of basal levels in the core and periphery of the lesion, respectively. In addition, we studied the delivery characteristics of several glutamate concentrations (10, 100 or 1000 mM in perfusate) during a 90-minute application into the cortex. The delivery of glutamate from the perfusate to the brain was about 33-38% in the first 30 min and afterwards 11 25% of the total in the perfusate. The results show that cortical application of glutamate changes the composition of the extracellular fluid, which could contribute to the development of the lesion.

Experimental and clinical monitoring of glucose by microdialysis

The aim of this investigation was to assess the use of cerebral extracellular glucose as a parameter for microdialytic monitoring in neurosurgical critical care patients. Samples were collected from four patients with severe head injury and one with subarachnoid haemorrhage for periods of 4.5-67 h. Glucose and lactate were analysed in the dialysates. The ratios of glucose to lactate were calculated to partially allow for changes in microdialytic conditions over time. On-line pH was measured for up to 3 days in three patients. In experiments with spontaneous hypertensive rats we found that extracellular glucose became unmeasurable in the ischemic zone after middle cerebral artery occlusion. Similarly, in 3 patients glucose became undetectable for several hours, and glucose/lactate tended to decrease during measurement. This was accompanied by high ICP in one patient, and by a hypoxic episode in another. In the two other patients glucose/lactate ratios showed a rising trend. Findings indicate that glucose, and the glucose/lactate ratio show some correlations with clinical course and are promising parameters for cerebral monitoring and therapeutic decision making.

Levels of water-soluble antioxidants in astrocytoma and in adjacent tumor-free tissue

The aim of the present study was to investigate the oxidative status in astrocytoma. Samples of brain tissue from the centre to the periphery of the tumor were obtained from 11 astrocytoma patients undergoing computer tomography-guided stereotaxic operation, who had been previously treated with the corticosteroid dexamethasone. Part of the sample was investigated histologically for clarification of tumor type, and the presence of neoplastic and non-neoplastic tissue and necrosis. The rest was used for the quantification of the antioxidants ascorbic acid, uric acid, glutathione and cysteine by high performance liquid chromatography, and for quantification of DNA. Levels of antioxidants were calculated as micrograms/g fresh tissue and mumol/g DNA, a parameter related to cell content. There was significantly more DNA in neoplastic samples than in non-neoplastic ones, indicating increased cell density. Uric acid (micrograms/g fresh tissue) was significantly increased in neoplastic compared with non-neoplastic tissue, and levels were even higher in necrotic tissue. There were no significant differences between neoplastic and non-neoplastic tissue levels of ascorbic acid, glutathione or cysteine, expressed as micrograms/g fresh tissue. However, when levels of these three compounds were expressed as mumol/g DNA, i.e. taking into account the higher cell density, ascorbic acid, glutathione and cysteine were significantly reduced in neoplastic samples compared with non-neoplastic ones. Results thus show that there are differences between the antioxidant levels in astrocytoma and non-neoplastic tissue, providing additional support for the hypothesis that free radicals play a role in tumor growth.

Neurochemical monitoring and on-line pH measurements using brain microdialysis in patients in intensive care

We will report on our preliminary findings using microdialysis to monitor three patients in intensive care with either severe head injury (SHI) or severe subarachnoid hemorrhage (SAH) for up to 72 hours. In addition, basal levels in uninjured brain were assessed during an extra-intracranial bypass operation. Samples were collected hourly or half-hourly (flow rate 2 microliters/min, perfusion medium 0.9% saline). Parameters measured were the antioxidants ascorbic acid, uric acid, glutathione and cysteine. In 2 patients, the pH of the dialysate (pHD) was also measured on-line with a specially constructed flow-through meter, and glucose and lactate levels were assessed in the dialysate. In patient 1 (SHI), there was practically no cerebral perfusion pressure because of high ICP; cysteine and lactate levels were very high and glucose not measurable. In patient 2 (SAH) a hypoxic episode was accompanied by increased uric acid and decreased glucose. In patient 3 (SHI), the pHD reflected normalisation of blood gases after hyperventilation. Results indicate that parameters are in the range known from experimental studies, and can be correlated with clinical situations. The pHD as valuable indicator of metabolic changes is also feasible bedside.

On-line monitoring of cerebral pH by microdialysis

An on-line pH meter that can be mounted in microdialysis systems is described. The pH monitoring system was tested in rat cortex before and after middle cerebral artery occlusion (focal ischemia model). After probe implantation, pH values in the dialysate quickly reached a stable level that depended on perfusion medium (6.72, Ringer; 6.47, 0.9% saline) and flow rate (2 microliters/min). During ischemia, pH values sank rapidly and significantly, whereas lactic and ascorbic acid levels in the dialysate increased 9- to 12-fold. The pH of the dialysate is lower than that of the extracellular fluid because the relative recovery of carbon dioxide is about twice that of bicarbonate at the flow rate used, as shown in in vitro experiments. The pH meter would provide useful additional information during monitoring for ischemia, not only in experimental situations but also during neurosurgical intensive care. In the latter case, the on-line pH value would be a bedside parameter enabling fast feedback for setting analytical priorities and making therapeutical decisions.

[Cerebral microdialysis in neurological and neurosurgical research and clinical application in neurology and neurosurgery]

Microdialysis of the cerebral extracellular space (CES) provides information on the cortical metabolic state by measurement of the concentrations of metabolites and transmitters as well as of the extracellular pH. In trauma patients, this kind of monitoring should reveal damage from secondary cortical ischemia in an early, hopefully reversible state. The method further allows in vivo measurement of drug levels in the CES and investigation of their effect on metabolism. Although microdialysis has mainly been used experimentally, it is now beginning to be applied clinically. We report on our experience with both experimental and clinical work.

Do chemo- and radiotherapy affect the DNA repair ability of lymphocytes?

The DNA repair ability of unstimulated lymphocytes damaged by ultraviolet irradiation was measured in a group of 15 breast cancer patients before surgery, and 3 to 5 years later a) after surgery alone (n = 6), or b) after surgery with additional chemo- and/or radiotherapy (n = 9). In group a) 3 out of 6 patients had reduced repair before and 2 out of 6 after surgery. In the group b) 4 out of 9 patients had reduced repair before surgery, and 9 out of 9 after surgery plus chemo/radiotherapy. These results confirm our previous finding that chemo/radiotherapy influences DNA repair negatively. Because of the known association between reduced DNA repair and cancer occurrence, this could increase the risk of a secondary tumour.

Measurement of low-molecular-weight antioxidants, uric acid, tyrosine and tryptophan in plaques and white matter from patients with multiple sclerosis

The levels of the antioxidants ascorbic acid, cysteine, reduced glutathione and alpha-tocopherol, of the free-radical marker uric acid and of the amino acids tyrosine and tryptophan were measured by means of high-pressure liquid chromatography in plaques, adjacent white matter and distant white matter from patients with multiple sclerosis, and in central nervous system tissue from patients without neurological diseases. Cholesterol and DNA were also determined, to check demyelination and cellularity. Uric acid was increased and glutathione correspondingly decreased in plaques; alpha-tocopherol was lowest in plaques and highest in distant white matter in all cases. Ascorbic acid, cysteine, tyrosine and tryptophan were not significantly changed in any tissue. The results provide evidence supporting the involvement of free radicals in multiple sclerosis.

Extracellular antioxidants and amino acids in the cortex of the rat: monitoring by microdialysis of early ischemic changes

Extracellular concentrations of ascorbic acid, glutathione, cysteine, uric acid, tyrosine, and tryptophan were monitored using intracerebral microdialysis in the left frontoparietal cortex of spontaneous hypertensive rats before, and for 3 h after, either focal ischemia [left middle cerebral artery occlusion (MCAO)] or sham operation. The size of the ischemic area and the position of the microdialysis probe were checked using the enzyme histotopochemical acid phosphatase reaction. The probe was always located in the cortex inside the stained area. Ascorbic acid levels rose immediately after MCAO and remained at about 12-fold for 3 h. There was a transient release of glutathione during 1-1.5 h. Uric acid concentrations were also increased but the differences did not reach significance. The levels of the amino acids tyrosine and tryptophan increased steadily after MCAO. The increases in cysteine were variable but significant. In some experiments, the pH of the dialysate was measured online. The parameters ascorbic acid, glutathione, cysteine, and pH are suitable for the early detection of cortical ischemic events by microdialysis.

Levels of low molecular weight scavengers in the rat brain during focal ischemia

Ascorbic acid, cysteine, glutathione, uric acid, tyrosine and tryptophan were quantified in samples of frontoparietal cortex, striatum, hippocampus and cerebellum from both sides of rat brain 0.5 h, 4 h and 24 h after focal ischemia. Cysteine, tyrosine and tryptophan were increased in cortex and striatum at 0.5 h, returning afterwards to normal. Uric acid was increased, whereas ascorbic acid and glutathione were correspondingly decreased. Although changes can be explained primarily by energy failure they are also consistent with free radical activity during early stages of ischemia.

Differences in the kinetics of DNA repair in cancer patients and healthy controls

The time course of DNA repair, using (3H)thymidine uptake as parameter, was measured during 8 h after a single exposure to 2, 8, and 16 UV-C J/m2 in lymphocytes of 8 cancer patients, 1 xeroderma pigmentosum patient and 10 controls. All patients had reduced repair, and all controls normal repair, as calculated 2 h after a single exposure. Six patients reached normal levels with a delay of 2-6 h, whereas 2 patients and the xeroderma pigmentosum patient did not. Although the kinetic curves in controls and patients had a similar form, those for 8 and 16 J/m2 in patients were shifted so that they corresponded to that of 2 J/m2 in controls. Additionally the ability to repair repeated damage (cells irradiated twice or three times at 2-hour intervals with doses of 2 or 8 J/m2) was investigated in 6 patients and in 7 controls. The incorporation values showed significant differences between patients and controls at each dose and time point. Cancer patients tend to repair repeated damage less efficiently than controls. Using these parameters subtle differences between the repair ability of individuals might be identified. Because of the known connection between reduced DNA repair and carcinogenesis, this might help to distinguish cancer-prone individuals.

Investigation of the repair of single-strand breaks in human DNA using alkaline gel electrophoresis

Unstimulated lymphocytes from eight healthy persons were exposed to 10-, 30-, and 100-Gy doses of 60Co gamma radiation. The repair of damaged DNA was measured by (1) alkaline gel electrophoresis (extracted DNA loaded on 0.25% agarose gel, run at 1 V/cm for 39-44 h) at 0, 1, and 2 h after exposure and (2) incorporation of [3H]thymidine into unstimulated lymphocytes in the presence of 2 mM hydroxyurea 1 and 2 h after exposure. Both methods--alkaline gel electrophoresis and thymidine incorporation--showed that repair was completed within 2 h.

Some pathophysiological aspects of experimental autoimmune encephalomyelitis

Three aspects of the pathophysiology of experimental autoimmune encephalomyelitis (EAE) are discussed: firstly, the possible electrophysiological effects in the CNS of myelin basic protein, which is released during demyelination; secondly, the partial degeneration of monoaminergic and glutamatergic neurons which occurs during an attack of EAE in addition to demyelination; thirdly, the importance of ischemic events, accompanied by free radical release, in EAE. Especially the third aspect could have therapeutic implications. Treatment with radical scavengers, N-methyl-D-aspartate receptor blockers, or calcium blockers (as suggested for ischemia) might prove effective for EAE. Our present aim is to investigate whether these results are also relevant for MS, for which EAE is an animal model.