Low-dose radiation exposure and protection against atherosclerosis in ApoE(-/-) mice: the influence of P53 heterozygosity

We recently described the effects of low-dose γ-radiation exposures on atherosclerosis in genetically susceptible (ApoE(-/-)) mice with normal p53 function. Doses as low as 25 mGy, given at either early or late stage disease, generally protected against atherosclerosis in a manner distinctly nonlinear with dose. We now report the influence of low doses (25-500 mGy) on atherosclerosis in ApoE(-/-) mice with reduced p53 function (Trp53(+/-)). Single exposures were given at either low or high dose rate (1 or 150 mGy/min) to female C57BL/6J ApoE(-/-) Trp53(+/-) mice. Mice were exposed at either early stage disease (2 months of age) and examined 3 or 6 months later, or at late stage disease (7 months of age) and examined 2 or 4 months later. In unirradiated mice, reduced p53 functionality elevated serum cholesterol and accelerated both aortic root lesion growth and severity in young mice. Radiation exposure to doses as low as 25 mGy at early stage disease, at either the high or the low dose rate, inhibited lesion growth, decreased lesion frequency and slowed the progression of lesion severity in the aortic root. In contrast, exposure at late stage disease produced generally detrimental effects. Both low-and high-dose-rate exposures accelerated lesion growth and high dose rate exposures also increased serum cholesterol levels. These results show that at early stage disease, reduced p53 function does not influence the protective effects against atherosclerosis of low doses given at low dose rate. In contrast, when exposed to the same doses at late stage disease, reduced p53 function produced detrimental effects, rather than the protective effects seen in Trp53 normal mice. As in the Trp53 normal mice, all effects were highly nonlinear with dose. These results indicate that variations in p53 functionality can dramatically alter the outcome of a low-dose exposure, and that the assumption of a linear response with dose for human populations is probably unwarranted.

Calcifying pseudoneoplasms of the neuraxis (CAPNON): clinical features and therapeutic options

INTRODUCTION

Calcifying pseudoneoplasms of the neuraxis (CAPNON) are rare, slow-growing lesions occurring anywhere in the central nervous system (CNS). Since their first description in 1978, only 39 cases have been reported in the literature.

METHODS

The cases of two patients with histopathologically verified diagnoses of CAPNON are presented. Thereafter, we review all reports published so far with respect to study type, number of patients, anatomical area (intracranial, spinal, or both), clinical presentation, radiological presentation, therapy, duration of follow-up, incidence and type of complication, and outcome. Furthermore, current recommendations for the management of spinal and cerebral CAPNON are discussed.

RESULTS

A total of 19 retrospective articles were identified and selected for review: 6 case series (31.6 %) and 13 reports of single cases (68.4 %). The 19 articles and our two additional cases added up to a total of 19 patients with spinal CAPNON and 22 patients with intracranial CAPNON. All patients were treated surgically. A follow-up was provided in 13 patients with spinal (68.4 %) and in 16 patients with intracranial CAPNON (72.7 %), respectively. The follow-up showed no signs of recurrence in 12 of 13 patients with spinal CAPNON (92.3 %) and in 15 of 16 patients with intracranial CAPNON (93.7 %). One-tailed Fisher's exact test revealed no significant difference between complete and incomplete resection in terms of disease recurrence (spinal: p = 0.6842; intracranial: p = 0.3749). Analysis of the literature did not reveal any deaths directly associated with CAPNON.

CONCLUSIONS

Calcifying pseudoneoplasms are rare benign lesions of the CNS of yet unknown origin. Because of the increasing number of reports, this clinical entity should be taken into consideration in the differential diagnosis of intracranial and intraspinal calcified lesions.

[Cervicobrachialgia - an update under special consideration of the surgical management]

The classic cervicobrachialgia results acutely from cervical nerve root compression by disc herniation or subacutely by radicular compression after progressive spondylotic changes of the cervical spine. The clinical presentation includes local and radiating pain syndromes that can be accompanied by sensorimotor deficits. Besides the medical history and a targeted clinical examination, supplementary radiographic means should be undertaken to confirm diagnosis. If no urgent surgical indication exists, conservative therapy should be initiated. However, with varying results of conservative and surgical therapy, chronic impairment can occur.

Surgical treatment of unruptured intracranial aneurysms in a low-volume hospital--outcome and review of literature

BACKGROUND

The aim of this study was to evaluate surgical outcome of unruptured intracranial aneurysms (UIAs) in a low-volume hospital and compare the results with the recent literature.

METHODS

A retrospective review of all consecutive craniotomies for UIA from July 1999 through June 2009 was performed. Morbidity was defined as modified Rankin Scale (mRS) ≥ 3 and evaluated six weeks after surgery. Cognitive function was evaluated at rehabilitation-to-home discharge. A PubMed database search (2001-2011) seeking retrospective, single-center studies reporting on surgical outcome of UIAs was performed.

RESULTS

There were 47 procedures performed in 42 patients to treat 50 UIAs (mean of 5 annual craniotomies). The mean age was 54.7 ± 12.1 years and mean aneurysm size was 7.6 ± 4.0mm. Favorable outcome (mRS 0-2) at six weeks after surgery was achieved in 45 of 47 procedures (95.7%). Aneurysm size ≥ 12 mm was statistically significant related to adverse outcome defined as mRS change ≥ 1 (71% vs. 29%; p = 0.018). Five patients (10.6%) with favorable neurological outcome (mRS 2) presented with cognitive impairment at rehabilitation-to-home discharge. There was no significant difference in overall morbidity and mortality comparing low- and high-volume hospitals (4.0% vs. 4.8%; p = 0.85).

CONCLUSIONS

Low-volume hospitals may achieve good results for surgical treatment of UIAs. The results indicate that defining numeric operative volume thresholds is not feasible to guide centralization of aneurysm treatment.

Radiosensitizing effect of epothilone B on human epithelial cancer cells

BACKGROUND

A combined modality treatment employing radiation and chemotherapy plays a central role in the management of solid tumors. In our study, we examined the cytotoxic and radiosensitive effect of the microtubule stabilizer epothilone B on two human epithelial tumor cell lines in vitro and its influence on the microtubule assembly.

METHODS

Cancer cells were treated with epothilone B in proliferation assays and in combination with radiation in colony-forming assays. For the analysis of ionizing radiation-induced DNA damage and the influence of the drug on its repair a γH2AX foci assay was used. To determine the effect of epothilone B on the microtubule assembly in cells and on purified tubulin, immunofluorescence staining and tubulin polymerization assay, respectively, were conducted.

RESULTS

Epothilone B induced a concentration- and application-dependent antiproliferative effect on the cells, with IC(50) values in the low nanomolar range. Colony forming assays showed a synergistic radiosensitive effect on both cell lines which was dependent on incubation time and applied concentration of epothilone B. The γH2AX assays demonstrated that ionizing radiation combined with the drug resulted in a concentration-dependent increase in the number of double-strand breaks and suggested a reduction in DNA repair capacity. Epothilone B produced enhanced microtubule bundling and abnormal spindle formation as revealed by immunofluorescence microscopy and caused microtubule formation from purified tubulin.

CONCLUSION

The results of this study showed that epothilone B displays cytotoxic antitumor activity at low nanomolar concentrations and also enhances the radiation response in the tumor cells tested; this may be induced by a reduced DNA repair capacity triggered by epothilone B. It was also demonstrated that epothilone B in fact targets microtubules in a more effective manner than paclitaxel.

Chemoradiotherapy duration correlates with overall survival in limited disease SCLC patients with poor initial performance status who successfully completed multimodality treatment

BACKGROUND AND PURPOSE

Limited data concerning treatment-related prognostic factors in limited disease (LD) small-cell lung cancer (SCLC) patients with poor initial performance status (PS) who successfully completed chemoradiotherapy (CRT) are available.

PATIENTS AND METHODS

A total of 125 patients with initial PS WHO 2-3 who successfully completed CRT were retrospectively reviewed. Thoracic radiation therapy (TRT) was applied in the concurrent (group 1) or sequential (group 2) mode. Influence of treatment type, time from diagnosis to start of TRT, number of chemotherapy cycles, prophylactic cranial irradiation (PCI), occurrence of brain metastases (BMs), and duration of CRT on overall survival (OS) were analyzed.

RESULTS

Median duration of CRT was 156 days in group 1 and 195 days in group 2 (p < 0.001). Median progression-free survival and OS were 11.6 (95% confidence interval (CI) 10-13.2) and 14.9 (95% CI 11.7-17.6) months with no difference between the groups. The 2- and 3-year survival rates were 37.9 ± 6.9% and 22.7 ± 6.3% in group 1 and 22.4 ± 4.9% and 15.2 ± 4.3% in group 2, respectively. Duration of CRT was only treatment-related factor predicting OS in the uni- (p < 0.014) and multivariate (p < 0.025) analyses. Short dose-dense CRT was associated with improved OS.

CONCLUSION

Duration of CRT affects OS in LD SCLC patients with poor initial performance status who successfully completed multimodality treatment.

[Radiation-related caries: etiology and possible preventive strategies. What should the radiotherapist know?]

BACKGROUND

After radiation treatment of head-and-neck cancer, the impairment of patient's quality of life still remains an issue. After completion of the treatment course, a substantial number of patients develop so-called radiation caries. In addition, almost 50% of all cases of infectious osteoradionecrosis (iORN) of the jaws are directly associated with radiation caries. This review addresses our current knowledge on the etiology and pathogenesis of radiation caries including possible preventive strategies.

MATERIALS AND METHODS

A PubMed search using the terms "radiation caries" ("radiation related caries", "radiation related damage to dentition") and "radiogenic caries" ("postradiation caries", "dental complications and radiotherapy") was performed. The analysis of its content focused on the etiology, the pathogenesis, and the available knowledge on prophylaxis as well as treatment of radiation caries.

RESULTS

For this review, 60 publications were selected. As main causal factors for radiogenic caries, either indirect impairment, resulting from alterations in the oral environment (e.g., radiation-induced xerostomia) or direct radiation-induced damage in teeth hard tissues are discussed. Radiation caries remains a lifelong threat and, therefore, requires permanent prevention programs.

CONCLUSION

To enable optimal medical care of the patients during the time course of radiotherapy as well as afterwards, close interdisciplinary cooperation between radiotherapists, oral surgeons, otorhinolaryngologists, and dentists is absolutely essential.

Search for clastogenic factors in the plasma of locally irradiated individuals

In studies reported in the 1960s and in several investigations since, plasma from irradiated individuals was shown to induce chromosomal aberrations when transferred into normal blood cultures. In the present study, the aim was to investigate the occurrence of these clastogenic factors (CF) using markers representing DNA damage produced in reporter lymphocytes that are treated with plasma from locally exposed individuals. Blood plasma was obtained from clinical patients with benign conditions before and after they had received radiation to small treatment volumes. Three patient groups were studied: (I) marginal resected basal cell carcinoma, (II) painful osteoarthritis of the knee, and (III) painful tendinitis of the elbow or the heel. Patients in each treatment group obtained the same fractionated treatment regimen, ranging from a total dose of 40 Gy (8 × 5 Gy, 2 factions/week) to a very small volume (1-3.5 cm³) in group I to a total dose of 6 Gy (6 × 1 Gy, 2 fractions/week) for groups II and III (treatment volumes 800-1150 cm³ and 80-160 cm³, respectively). The presence of CF in the plasma was investigated through cytogenetic (chromosomal aberrations, micronuclei) assays and kinetics of early DNA damage (γ-H2AX foci) in reporter cells. With the experimental settings applied, local radiation exposure had no apparent effect on the induction of CF in patient plasma; no deviations in chromosomal aberrations or micronucleus or focus induction were observed in reporter cells treated with postexposure plasma with respect to pre-exposure samples when the mean values of the groups were compared. However, there was a large interindividual variation in the plasma-induced DNA-damaging effects. Steroid treatment of patients was demonstrated to be the most influential factor affecting the occurrence of plasma factors; plasma from patients treated with steroids led to significant reductions of γ-H2AX foci and reduced numbers of chromatid aberrations in reporter cells. In addition to the locally exposed patients, newly obtained plasma samples from three radiological accident victims exposed in 1994 were examined. In contrast to the patient data, a significant increase in chromosomal aberrations was induced with plasma from two accident victims.

[The lumbar disc herniation - management, clinical aspects and current recommendations]

Lumbar disc herniation has a high prevalence and strong social-medical impact. Patients suffer from lower back pain that radiates from the spine. Loss of sensation or paresis adds to the clinical picture. The diagnosis should be confirmed by imaging in patients considered for surgery. High remission rates initially warrant conservative treatment (adequate analgesia and physiotherapy) in many patients. If this treatment does not lead to significant alleviation within 5-8 weeks, surgery should be performed to reduce the risk of chronic nerve affection. Posterior interlaminar fenestration is the intervention primarily conducted for this diagnosis. A relapse in the same region occurs in up to 10% of patients after months through years, which sometimes necessitates a reoperation if symptoms are pertinent.

[Cerebral arteriovenous malformations: clinical aspects and treatment possibilities]

Cerebral arteriovenous malformations (AVM) are vascular lesions that occur either congenitally or arise in early childhood. AVM are characterised by arteriovenous shunts through a nidus of coiled and tortuous vascular connections that connect feeding arteries to draining veins. Generally, AVM become evident through intracranial haemorrhage in patients aged 20-40 years. Especially, in the young adult presenting with epileptic seizures or focal neurological deficits AVM needs to be considered as an important differential diagnosis. Treatment modalities for the occlusion of symptomatic AVM include microneurosurgery, endovascular embolisation, or radiosurgery. These can be performed each on its own or in combination with the others. Incidentally diagnosed AVM require a thorough and individual consideration of treatment indications. This review deals with the current recommendations for the treatment of AVM in the adult patient.

[Spinal tumors - part 2: intradural tumors. Epidemiology, clinical aspects and therapy]

Intradural spinal tumors are classified in extra- and intramedullary tumors. The most frequent intradural-extramedullary tumors are meningiomas and neurinomas. Among the intradural-intramedullary tumors the most frequent ones are ependymomas and astrocytomas. Independent of their origin, spinal tumors usually manifest with progressive local or radicular pain and neurological deficits. The treatment of choice for most of these tumors is a complete surgical resection. In tumors with infiltrative growth into the intramedullary area, a marginal tumor tissue has to be left in situ in order to avoid additional neurological deficits. In particular if neurological deficits appear, a fast surgical intervention is indicated, since the prognosis depends on duration and severity of the preoperative existing deficits. Below, clinical presentation and relevant treatment options of spinal intradural tumors are discussed.

[Spinal tumors - part 1: extradural tumors. Epidemiology, clinical aspects and therapy]

Spinal tumors are classified according to their location in extradural, intradural-extramedullary, and intradural-intramedullary tumors. The most frequent extradural tumors are metastases. Primary spinal tumors are rare and predominantly benign. Independent of their origin, spinal tumors manifest themselves with progressive local or radicular pain and neurological deficits. A preferably early diagnosis and subsequent therapy is important to improve the prognosis. The treatment of choice for most of these tumors is the complete surgical resection. In particular with the occurrence of neurological deficits a fast surgical intervention is indicated, since the prognosis depends on duration and severity of the preoperative existing deficits. Below, clinical presentation and relevant treatment options of spinal extradural tumors are discussed.

[Adult syringomyelia - a syndrome of different origins]

Syringomyelia describes an intra-medullary cyst in the spinal cord. In the adult patient, the pathology mostly results from Chiari-I-malformation or from severe spinal trauma. The clinical picture varies broadly, but symptoms often include pain and progressive neurologic deficits. During the clinical course, muscular atrophy and loss of pain and temperature sensation may develop in the affected region. Today, magnet resonance imaging helps to detect syringomyelia at an early stage. The interdisciplinary therapeutic approach includes an adequate pain treatment and physiotherapy, in selected cases a surgical intervention by an experienced surgeon. If not treated surgically, most symptomatic patients experience progressive neurologic deficits that may lead to severe paragplegia and chronic neuropathic pain.

[Deep brain stimulation - options and limits]

Deep brain stimulation (DBS) is meanwhile an established procedure. It has been employed for several neurological diseases with impressive therapeutic responses to some extent. Stimulation of the ventral intermediate nucleus of the thalamus can distinctively improve tremor associated with essential tremor or Parkinson disease. Similarly, stimulation of the subthalamic nucleus or the globus pallidus internus can substantially diminish bradykinesia, rigidity, and tremor. Additionally, by means of a reduced dopaminergic therapy, it can lead to an improvement of the L-Dopa induced dyskinesias in patients with Parkinson disease. In recent years, DBS has also been used for other neurological and psychiatric diseases. Yet, the exact mechanism of action on a neuronal level remains uncertain. Regardless of the underlying disease and the surgical electrode positioning, a meticulous patient selection and correct indication is of paramount importance for the therapeutic success.

Low-dose radiation exposure and atherosclerosis in ApoE⁻/⁻ mice

The hypothesis that single low-dose exposures (0.025-0.5 Gy) to low-LET radiation given at either high (about 150 mGy/min) or low (1 mGy/min) dose rate would promote aortic atherosclerosis was tested in female C57BL/6J mice genetically predisposed to this disease (ApoE⁻/⁻). Mice were exposed either at an early stage of disease (2 months of age) and examined 3 or 6 months later or at a late stage of disease (8 months of age) and examined 2 or 4 months later. Changes in aortic lesion frequency, size and severity as well as total serum cholesterol levels and the uptake of lesion lipids by lesion-associated macrophages were assessed. Statistically significant changes in each of these measures were observed, depending on dose, dose rate and disease stage. In all cases, the results were distinctly non-linear with dose, with maximum effects tending to occur at 25 or 50 mGy. In general, low doses given at low dose rate during either early- or late-stage disease were protective, slowing the progression of the disease by one or more of these measures. Most effects appeared and persisted for months after the single exposures, but some were ultimately transitory. In contrast to exposure at low dose rate, high-dose-rate exposure during early-stage disease produced both protective and detrimental effects, suggesting that low doses may influence this disease by more than one mechanism and that dose rate is an important parameter. These results contrast with the known, generally detrimental effects of high doses on the progression of this disease in the same mice and in humans, suggesting that a linear extrapolation of the known increased risk from high doses to low doses is not appropriate.

[The intracranial meningioma - therapeutic possibilities and limitations]

Meningiomas are common intracranial tumours that arise from arachnoidal cells. Clinically they often manifest by headache, focal or generalized seizures, or neurologic deficits as a result of brain compression. More than 90 percent of these mostly slow growing meningiomas are benign. In symptomatic patients a resection should be performed with the intention to cure or at least alleviate symptoms. In cases of subtotal resection an adjuvant radiotherapy should be deliberated. Stereotactic radiotherapy as initial treatment is an effective alternative for meningiomas, especially in patients not suitable for surgery due to various reasons. In patients that are refractory to treatment or with unresectable disease a hormonal- or chemotherapy can be considered.

[Chronic subdural hematoma - assessment and management]

Subdural hematomas (SDH) are associated with an increased morbidity and mortality and generally occur as chronic SDH among older patients. The most frequent signs and symptoms - like headache, alteration of consciousness, gait impairment and hemiparesis - are also prevalent among other diseases, which has to be taken into account in the differential diagnosis. In the case of symptomatic patients with focal neurological deficits, a surgical intervention should be considered, whereas in case of asymptomatic patients or patients with only slight headaches, also a conservative treatment with a clinical and radiological follow-up might be a possibility. Also after surgical intervention, the recurrence rate is between 5 and 33%. Therefore, all patients with chronic SDH depict, irrespective of the indication for an oral anticoagulation, a challenge for the treating physicians.

[Craniopharyngioma--a "geographical malignant" tumour]

The craniopharyngioma is a rare dysontogenetic tumour that originates from either scattered cells of the craniopharyngeal duct or from metaplastically mutated anterior pituitary parenchyma cells. Despite being classified as a WHO-Class-I tumour, the histologically benign craniopharyngioma may display an aggressive behaviour. Like other congenital tumours, it usually becomes manifest within the first two decades of life. Patients typically complain of headache and a chiasma syndrome with bitemporal hemianopsy may develop depending on tumour localisation. In children, anterior pituitary insufficiency often manifests as growth restriction. Additionally, diabetes insipidus and other hormonal disturbances may develop. Therapeutically either radical total removal or subtotal resection in combination with postoperative radiation is recommended. In cystic tumors, stereotactic cyst drainage and adjuvant radiation may be a possible alternative. The prognosis is best in patients who are diagnosed early.

[Aneurysmal subarachonid haemorrhage]

The most characteristic symptom of an aneurysmal subarachnoid haemorrhage (aSAH) is a sudden onset of severe headache, which can be accompanied by meningism, impaired consciousness, and vegetative symptoms. A cerebral CT scan is the initial diagnostic tool of choice if aSAH is suspected. The localisation and morphology of the aneurysm is depicted in a CT-angiography and/or conventional panangiography. Until definitive exclusion of the aneurysm by either microsurgical clipping or endovascular coiling, rebleeding should be avoided implicitly. The postoperative phase, especially in patients with severe aSAH is embossed with the occurrence of disease-specific complications (cerebral vasospasm, intracranial hypertension, seizure disorder, hydrocephalus) and consecutively increased risk for secondary brain injury. Furthermore, many patients present systemic complications such as electrolyte disturbances and cardiac dysfunctions. Early identification and therapy of cerebral and systemic complications are very important in order improve functional outcome.

Transgenerational developmental effects and genomic instability after X-irradiation of preimplantation embryos: studies on two mouse strains

Recent results have shown that irradiation of a single cell, the zygote or 1-cell embryo of various mouse strains, could lead to congenital anomalies in the fetuses. In the Heiligenberger strain, a link between the radiation-induced congenital anomalies and the development of a genomic instability was also suggested. Moreover, further studies showed that in that strain, both congenital anomalies and genomic instability could be transmitted to the next generation. The aim of the experiments described in this paper was to investigate whether such non-targeted transgenerational effects could also be observed in two other radiosensitive mouse strains (CF1 and ICR), using lower radiation doses. Irradiation of the CF1 and ICR female zygotes with 0.2 or 0.4Gy did not result in a decrease of their fertility after birth, when they had reached sexual maturity. Moreover, females of both strains that had been X-irradiated with 0.2Gy exhibited higher rates of pregnancy, less resorptions and more living fetuses. Additionally, the mean weight of living fetuses in these groups had significantly increased. Exencephaly and dwarfism were observed in CF1 fetuses issued from control and X-irradiated females. In the control group of that strain, polydactyly and limb deformity were also found. The yields of abnormal fetuses did not differ significantly between the control and X-irradiated groups. Polydactyly, exencephaly and dwarfism were observed in fetuses issued from ICR control females. In addition to these anomalies, gastroschisis, curly tail and open eye were observed at low frequencies in ICR fetuses issued from X-irradiated females. Again, the frequencies of abnormal fetuses found in the different groups did not differ significantly. In both CF1 and ICR mouse strains, irradiation of female zygotes did not result in the development of a genomic instability in the next generation embryos. Overall, our results suggest that, at the moderate doses used, developmental defects observed after X-irradiation of female zygotes of these two sensitive mouse strains should not be transmitted to the next generation. Paradoxically, other studies would be needed to address the question of a potential increase of fertility after doses lower than 0.2Gy in both strains.

Review and meta-analysis of epidemiological associations between low/moderate doses of ionizing radiation and circulatory disease risks, and their possible mechanisms

Although the link between high doses of ionizing radiation and damage to the heart and coronary arteries has been well established for some time, the association between lower-dose exposures and late occurring cardiovascular disease has only recently begun to emerge, and is still controversial. In this paper, we extend an earlier systematic review by Little et al. on the epidemiological evidence for associations between low and moderate doses of ionizing radiation exposure and late occurring blood circulatory system disease. Excess relative risks per unit dose in epidemiological studies vary over at least two orders of magnitude, possibly a result of confounding and effect modification by well-known (but unobserved) risk factors, and there is statistically significant (p < 0.00001) heterogeneity between the risks. This heterogeneity is reduced, but remains significant, if adjustments are made for the effects of fractionated delivery or if there is stratification by endpoint (cardiovascular disease vs. stroke, morbidity vs. mortality). One possible biological mechanism is damage to endothelial cells and subsequent induction of an inflammatory response, although it seems unlikely that this would extend to low-dose and low-dose-rate exposure. A recent paper of Little et al. proposed an arguably more plausible mechanism for fractionated low-dose effects, based on monocyte cell killing in the intima. Although the predictions of the model are consistent with the epidemiological data, the experimental predictions made have yet to be tested. Further epidemiological and biological evidence will allow a firmer conclusion to be drawn.

[Glioblastoma multiforme--new hope due to modern therapeutical approaches]

Glioblastoma multiforme (GBM) is the most frequently encountered malignant cerebral tumor. Despite significant improvements in the treatment of GBM, this disease remains associated with a high morbidity and mortality, with more than half of all affected patients dying within the first year after diagnosis. Typical symptoms include focal neurological symptoms, seizures, personality changes and neurocognitive symptoms. GBM can be identified by means of cerebral imaging modalities and subsequently confirmed histopathologically through biopsy or resection. At present, surgical resection followed by radiotherapy with concomitant chemotherapy with temozolomide and subsequent adjuvant chemotherapy with temozolomide is considered the standard therapy for patients with GBM. Currently, many interdisciplinary studies with glioblastoma patients are accomplished with the aim to further improve the prognosis of the affected patients.

[Carpal tunnel syndrome--modern diagnostic and management]

The carpal tunnel syndrome is the most common entrapment neuropathy (about 3% of the adults are affected). It is characterized by pain and paresthesia along the distribution of the median nerve. Thenar muscle atrophy with corresponding muscle weakness is a late manifestation of advanced disease. Electrophysiological tests are helpful in suggesting the diagnosis. An imaging with a magnetic resonance tomography may be used in the diagnosis of atypical cases. Ergonomic manoeuvres, oral steroids and steroidal injections may alleviate symptoms in mild cases. Surgical decompression of the carpal tunnel is the classical treatment of severe cases as well as for those who do not respond to conservative treatment. After surgery patients usually show excellent results. The following article discusses clinical aspects, diagnosis and current therapeutic options.

[Trigeminal neuralgia - pathophysiology, clinical aspects and treatment]

The trigeminal neuralgia is characterised by paroxysmal appearing fulgurous stabbing pain. Its medical condition is caused through a local-circumscribed demyelinisation of the trigeminal nerve with consecutive conduction of salting impulses on afferent pain fibres. It is essential to differentiate the symptomatic from the idiopathic trigeminal neuralgia. As primary management, a pharmacological treatment with anticonvulsants is recommended in order to attenuate the ectopic-generated pain impulses. Different neurosurgical procedures are available in cases of resistance to therapy. Thereby, causal surgery in form of microvascular decompression is not only the operative treatment of choice, but because of the excellent results also a fundamental support of the theory of vascular compression. A comprehensive knowledge about diagnosis and management of trigeminal neuralgia is essential to treat patients efficiently and successfully. This synopsis summarises the current recommendations concerning diagnostics and therapeutic options.

High-dose-rate brachytherapy for intranasal tumours in dogs: results of a pilot study

This prospective study describes the feasibility and toxicity of (192)Iridium high-dose-rate (HDR) brachytherapy as an alternative strategy for the treatment of canine intranasal tumours. Fifteen dogs with malignant intranasal tumours were treated twice weekly using a hypofractionated protocol with eight fractions, 5 Gy per fraction, resulting in a total dose of 40 Gy. Acute and chronic adverse side-effects appeared to be rare. Only 7% of the acute side-effects and 5% of the chronic were classified as severe (grade 3). Eight dogs showed clinical complete remission, and five dogs had partial remission, with a resolution of tumour-related symptoms. Magnetic resonance imaging showed a reduced tumour mass in 12 cases. Median survival time was 17 months (range 4-48 months), with four dogs (three without disease) still alive. Median time to recurrence of these dogs was 14 months. In nine dogs, progression or recurrence of the tumour was the cause of death. This study suggests that HDR brachytherapy is feasible and well tolerated.

Pharmaceutical and cellular strategies in prophylaxis and treatment of graft-versus-host disease

Acute and chronic GVHD after allogeneic hematopoetic stem cell transplantation are still associated with significant morbidity and mortality. For prophylaxis of acute GVHD calcineurin inhibitors in combination with an antimetabolite (MTX or MMF) are administered, and these therapies are based on controlled studies. New prophylaxis strategies include mTOR-inhibitors in combination with tacrolimus but require confirmation by controlled trials. First-line treatment of acute GVHD consists mainly of steroids with doses ranging from 1 mg/kg/day prednisone to 3 mg/kg/day methylprednisolone. Second-line treatment of acute GVHD after failure of steroids is less well defined due to the lack of controlled studies. Treatment options are the use of cytotoxic antibodies (ATG, campath), cytokine blocking agents (etanercept, daclizumab), immunomodulating modalities (photopheresis), and antimetabolites (pentostatin, MMF). Recently, cellular approaches were developed, such as the adoptive transfer of mesenchymal stem cells. Nevertheless steroid-resistant acute GVHD is still a main challenge in alloHSCT and associated with high mortality. First-line treatment of chronic GVHD is also based on steroids with 1 mg/kg/day prednisolone or prednisone, which are often combined with calcineurin inhibitors. There is no consensus on second-line treatment of chronic GVHD and most therapies are solely based on phase II trials. Treatment options are the use of immunomodulating modalities (photopheresis, mTOR-inhibitors) and antimetabolites (MMF, MTX, pentostatin). Recent reports showed an efficacy of rituximab in selected patients. Other treatment options are low dose total nodal irradiation or the use of antibodies like ATG. Moreover, successful topical treatment of manifestations of chronic GVHD manifestations has been reported consisting of topical steroids like budesonide, topical calcineurin inhibitors, or PUVA.

[Traumatic dissection of extra- and intradural arteries]

Dissection of extra- and intradural arteries is a common cause of cerebral insult in younger patients (<45 years). In patients with corresponding craniocervical injury and symptoms (carotidynie, ipsilateral headache, partial Horner syndrome, cranial nerve palsy) arterial dissection is always to be considered. Essential in diagnosing arterial dissection is the verification of the intramural hematoma and morphologic changes in the vessel (stenosis, pseudoaneurysm) by means of CT/CTA (acute phase) or MRI/MRA (subacute phase). These patients need to be monitored in an intensive care unit setting. The acute therapy includes anticoagulation or inhibition of thrombocyte aggregation. We present two cases with delayed cerebral infarction due to traumatic extra- and intradural arterial dissection after a motor vehicle accident. To perform primary diagnostic quickly and adequately may avoid permanent neurological deficit in these patients.

[Idiopathic normal pressure hydrocephalus]

Normal pressure hydrocephalus (NPH) is characterized by the classic triad of symptoms including gait disturbance, urinary incontinence, and dementia. Gait impairment represents the cardinal symptom. NPH is associated with a radiological verifiable ventriculomegaly in the absence of elevated cerebrospinal fluid (CSF) pressure. Because many patients do not present with classical clinical and radiological findings, its diagnosis and management represents a challenge for the general practitioner, neurologist and neurosurgeon. Various supplemental preoperative tests, including lumbar CSF tap test or CSF outflow resistance determination, can improve the accuracy of predicting a response to surgical intervention. CSF shunt results in significant symptoms in the majority of appropriately evaluated patients. The following article discusses clinical aspects, diagnosis and current therapeutic options.

Low‐dose radiotherapy (LD‐RT) and the modulation of iNOS expression in adjuvant‐induced arthritis in rats

PURPOSE

Low-dose radiotherapy (LD-RT) of arthritic joints applied during the peak of the acute inflammatory response improves the clinical and histomorphological development of adjuvant arthritis. The study was undertaken to investigate the cellular composition of the inflammatory infiltrate and the expression of the pro-inflammatory and anti-inflammatory enzymes, inducible nitric oxide synthase (iNOS), cyclo-oxygenase 2 (COX-2) and haem-oxygenase 1 (HO-1), in response to LD-RT.

MATERIALS AND METHODS

Adjuvant arthritis in female Lewis rats was induced by intradermal injection of heat-inactivated mycobacterium tuberculosis on day 0. Both arthritic hind paws were sham irradiated (group 1) or X-irradiated with either 5 x 1.0 Gy (group 2) or 5 x 0.5 Gy (group 3) from days 15 to 19 after induction (15 animals/group). On days 21 (n=12 joints/group) and 30 (n=18 joints/group), cryostat sections were analysed histologically and immunohistologically after specific staining for macrophages, iNOS, COX-2 and HO-1.

RESULTS

A total of 5 x 1.0 Gy or 5 x 0.5 Gy led to a significant reduction of clinical symptoms from days 21 to 29, and a highly significant reduction of cartilage and bone destruction on day 30. Macrophage-positive areas could be detected continuously throughout the periarticular infiltrate, and were slightly reduced after LD-RT on days 21 and 30. This reduction was more pronounced after 5 x 1.0 Gy. Following LD-RT, the iNOS score was reduced by about 45-50% on days 21 (p<0.05) and 30 (p<0.001). In contrast, the HO-1 score was increased by about 50% on days 21 (p=0.08) and 30 (p=0.03).

CONCLUSIONS

The clinically and histologically observed prevention of the progression of adjuvant arthritis after LD-RT given during the peak of the acute inflammatory response and the reduction of cartilage and bone destruction in the chronic phase appears to be related to the modulation of iNOS activity by low X-ray doses.

[Web based audiovisual patient information system--a pilot study of the preoperative patient information]

A considerable part of the medical clinical daily routine incorporates the information of patients about medical diagnosis and especially about the scheduled operative intervention. The disease pattern, the course in the hospital before and after surgery and the operation itself will be discussed during these conversations. The patient has to be informed about all potential complications from a medico legal point of view. To optimise information delivery, auxiliary materials like charts, pictures, X-rays and models are used. Unfortunately, only a small percentage of the presented information is assimilated by the patient after strict verbal information. To inform patients better and earlier about medical details and internal processes before the operation, we developed a web-based audiovisual patient information system with a combination of pictures, text, tone and video about surgical interventions. The patient satisfaction could be markedly improved by the application of this patient information system in the informed consent process. Furthermore, the use of the web-based multimedia information portal may leads to an essential time saving for the medical staff.

[Fluorescence guided resection of malignant brain tumors - breakthrough in the surgery of brain tumors]

Malignant gliomas, among others the glioblastoma multiforme, are the most frequent brain tumors. The glioblastoma itself represents the most unfavorable tumor. In Switzerland, about 450 humans contract a glioblastoma each year. The median survival time is under 12 months, thus the prognosis is dismal despite a combination of surgery, radiotherapy and chemotherapy. Surgical resection presents the major constituent in the management of patients with a glioblastoma. Postoperative radio- and chemotherapy have beneficial effects on the survival time and quality of life. Surgical removal of glioblastomas is challenging due to their infiltrative growth pattern. Therefore, the target extent of resection can only be achieved partially. For some time now, a new in Germany developed method is used in the Neurosurgical Clinic of the Cantonal Hospital in St. Gallen: The 5-ALA-guided microsurgical resection method allows a targeted and secure surgical resection of the tumor. A preoperative administered substance colors the tumor and makes it better visible for the neurosurgeon. Consequently, the healthy brain tissue can be better distinguished from the tumor. This permits not only a larger complete surgical resection of the tumor but also minimizes the resection of healthy tissue.