High sensitivity of host Helios+/Neuropilin-1+ Treg to pretransplant conditioning hampers development of OX40bright/integrin-ß7+ regulatory cells in acute gastrointestinal GvHD.

This study sought to compare the behavior of Treg subsets displaying different coexpression patterns of Neuropilin-1 (Nrp1) and Helios, under the influence of gut stress unrelated to hematopoietic stem cell transplantation, pretransplantation conditioning, and posttransplant gastrointestinal acute graft versus host disease (GI-aGvHD). Host CD4+/CD25hi/Foxp3+ Treg cells, identified by flow cytometry, were isolated from various tissues of mice affected by these stressors. Expression of CD25, CTLA-4, CD39, OX40, integrin-ß7, LAG3, TGFß/LAP, granzyme-A, -B, and interleukin-10 was compared in four Treg subsets displaying Helios or Nrp1 only, both or none. Fluorescence-activated cell sorter-sorted Treg subsets, displaying markers affected in a conditioning- and GI-aGVHD-restricted manner, were further investigated by transcriptome profiling and T-cell suppression assays. We found that conditioning by irradiation greatly diminished the relative frequency of Helios+/Nrp1+ Treg, shifting the balance toward Helios-/Nrp1- Treg in the host. Upregulation of integrin-ß7 and OX40 occurred in GI-aGvHD-dependent manner in Helios+/Nrp1+ cells but not in Helios-/Nrp1- Treg. Sorted Treg subsets, confirmed to overexpress Nrp1, Helios, OX40, or integrin-ß7, displayed superior immunosuppressive activity and enrichment in activation-related messenger RNA transcripts. Our data suggest that conditioning-induced shrinkage of the Nrp1+/Helios+ Treg subset may contribute to the development of GI-GvHD by impairing gut homing and decreasing the efficiency of Treg-mediated immunosuppression.

The miRNA Content of Bone Marrow-Derived Extracellular Vesicles Contributes to Protein Pathway Alterations Involved in Ionising Radiation-Induced Bystander Responses.

Extracellular vesicles (EVs), through their cargo, are important mediators of bystander responses in the irradiated bone marrow (BM). MiRNAs carried by EVs can potentially alter cellular pathways in EV-recipient cells by regulating their protein content. Using the CBA/Ca mouse model, we characterised the miRNA content of BM-derived EVs from mice irradiated with 0.1 Gy or 3 Gy using an nCounter analysis system. We also analysed proteomic changes in BM cells either directly irradiated or treated with EVs derived from the BM of irradiated mice. Our aim was to identify key cellular processes in the EV-acceptor cells regulated by miRNAs. The irradiation of BM cells with 0.1 Gy led to protein alterations involved in oxidative stress and immune and inflammatory processes. Oxidative stress-related pathways were also present in BM cells treated with EVs isolated from 0.1 Gy-irradiated mice, indicating the propagation of oxidative stress in a bystander manner. The irradiation of BM cells with 3 Gy led to protein pathway alterations involved in the DNA damage response, metabolism, cell death and immune and inflammatory processes. The majority of these pathways were also altered in BM cells treated with EVs from mice irradiated with 3 Gy. Certain pathways (cell cycle, acute and chronic myeloid leukaemia) regulated by miRNAs differentially expressed in EVs isolated from mice irradiated with 3 Gy overlapped with protein pathway alterations in BM cells treated with 3 Gy EVs. Six miRNAs were involved in these common pathways interacting with 11 proteins, suggesting the involvement of miRNAs in the EV-mediated bystander processes. In conclusion, we characterised proteomic changes in directly irradiated and EV-treated BM cells, identified processes transmitted in a bystander manner and suggested miRNA and protein candidates potentially involved in the regulation of these bystander processes.

[Neurosurgical management for metastatic brain tumors in renal cell carcinoma]. / Oligometasztatikus vesesejtes karcinóma idegsebészi ellátásának technikái és indikációi agyi áttétek esetén.

The therapeutic approach to brain metastases has changed significantly in the last 30 years. The development of surgical technique, the use of new MRI techniques, preoperative surgical planning and the administration of intraoperative navigation reduced the risks of surgery and improved the results. In the case of aggressive renal cell carcinomas, we detect brain metastases relatively often, which are difficult to treat, but the improved surgical and radiosurgery techniques can also be used with success. In our report, we present the neurosurgical management of metastatic spreading of renal cell carcinoma to the brain. Modern surgical planning and more precise, tailored approach with modern radiosurgery techniques are able to improve the outcome and prolong survival even in aggressive types of renal cell carcinomas that give rise to brain metastases. In more severe cases and even in the case of multiple brain metastases, cranial surgery can be recommended.

A method for early diagnosis of lung cancer from tumor originated DNA fragments using plasma cfDNA methylome and fragmentome profiles.

Early detection is critical for minimizing mortality from cancer. Plasma cell-free DNA (cfDNA) contains the signatures of tumor DNA, allowing us to quantify the signature and diagnose early-stage tumors. Here, we report a novel tumor fragment quantification method, TOF (Tumor Originated Fragment) for the diagnosis of lung cancer by quantifying and analyzing both the plasma cfDNA methylation patterns and fragmentomic signatures. TOF utilizes the amount of ctDNA predicted from the methylation density information of each cfDNA read mapped on 6243 lung-tumor-specific CpG markers. The 6243 tumor-specific markers were derived from lung tumor tissues by comparing them with corresponding normal tissues and healthy blood from public methylation data. TOF also utilizes two cfDNA fragmentomic signatures: 1) the short fragment ratio, and 2) the 5' end-motif profile. We used 298 plasma samples to analyze cfDNA signatures using enzymatic methyl-sequencing data from 201 lung cancer patients and 97 healthy controls. The TOF score showed 0.98 of the area under the curve in correctly classifying lung cancer from normal samples. The TOF score resolution was high enough to clearly differentiate even the early-stage non-small cell lung cancer patients from the healthy controls. The same was true for small cell lung cancer patients.

Clinical parameters predict the effect of bilateral subthalamic stimulation on dynamic balance parameters during gait in Parkinson's disease.

We investigated the effect of deep brain stimulation on dynamic balance during gait in Parkinson's disease with motion sensor measurements and predicted their values from disease-related factors. We recruited twenty patients with Parkinson's disease treated with bilateral subthalamic stimulation for at least 12 months and 24 healthy controls. Six monitors with three-dimensional gyroscopes and accelerometers were placed on the chest, the lumbar region, the two wrists, and the shins. Patients performed the instrumented Timed Up and Go test in stimulation OFF, stimulation ON, and right- and left-sided stimulation ON conditions. Gait parameters and dynamic balance parameters such as double support, peak turn velocity, and the trunk's range of motion and velocity in three dimensions were analyzed. Age, disease duration, the time elapsed after implantation, the Hoehn-Yahr stage before and after the operation, the levodopa, and stimulation responsiveness were reported. We individually calculated the distance values of stimulation locations from the subthalamic motor center in three dimensions. Sway values of static balance were collected. We compared the gait parameters in the OFF and stimulation ON states and controls. With cluster analysis and a machine-learning-based multiple regression method, we explored the predictive clinical factors for each dynamic balance parameter (with age as a confounder). The arm movements improved the most among gait parameters due to stimulation and the horizontal and sagittal trunk movements. Double support did not change after switching on the stimulation on the group level and did not differ from control values. Individual changes in double support and horizontal range of trunk motion due to stimulation could be predicted from the most disease-related factors and the severity of the disease; the latter also from the stimulation-related changes in the static balance parameters. Physiotherapy should focus on double support and horizontal trunk movements when treating patients with subthalamic deep brain stimulation.

Predicting the true extent of glioblastoma based on probabilistic tractography.

Glioblastoma is the most frequent type of primary brain tumors. Despite the advanced therapy, most of the patients die within 2 years after the diagnosis. The tumor has a typical appearance on MRI: a central hypointensity surrounded by an inhomogeneous, ring-shaped contrast enhancement along its border. Too small to be recognized by MRI, detached individual tumor cells migrate along white matter fiber tracts several centimeters away from the edge of the tumor. Usually these cells are the source of tumor recurrence. If the infiltrated brain areas could be identified, longer survival time could be achieved through supratotal resection and individually planned radiation therapy. Probabilistic tractography is an advanced imaging method that can potentially be used to identify infiltrated pathways, thus the real extent of the glioblastoma. Our study consisted of twenty high grade glioma patients. Probabilistic tractography was started from the tumor. The location of tumor recurrence on follow-up MRI was considered as the primary infiltrated white matter tracts. The results of probabilistic tractography were evaluated at thirteen different thresholds. The overlap with the tumor recurrence of each threshold level was then defined to calculate the sensitivity and specificity. In the group level, sensitivity (81%) and specificity (90%) were the most reliable at 5% threshold level. There were two outliers in the study group, both with high specificity and very low sensitivity. According to our results, probabilistic tractography can help to define the true extent of the glioblastoma at the time of diagnosis with high sensitivity and specificity. Individually planned surgery and irradiation could provide a better chance of survival in these patients.

Factors affecting postural instability after more than one-year bilateral subthalamic stimulation in Parkinson's disease: A cross-sectional study.

BACKGROUND: Balance impairment in Parkinson's disease is multifactorial and its changes due to subthalamic stimulation vary in different studies. OBJECTIVE: We aimed to analyze the combination of predictive clinical factors of balance impairment in patients with Parkinson's disease treated with bilateral subthalamic stimulation for at least one year. METHODS: We recruited 24 patients with Parkinson's disease treated with bilateral subthalamic stimulation and 24 healthy controls. They wore an Opal monitor (APDM Inc.) consisting of three-dimensional gyroscopes and accelerometers in the lumbar region. We investigated four stimulation conditions (bilateral stimulation OFF, bilateral stimulation ON, and unilateral right- and left-sided stimulation ON) with four tests: stance on a plain ground with eyes open and closed, stance on a foam platform with eyes open and closed. Age, disease duration, the time elapsed after implantation, levodopa, and stimulation responsiveness were analyzed. The distance of stimulation location from the subthalamic motor center was calculated individually in each plane of the three dimensions. We analyzed the sway values in the four stimulation conditions in the patient group and compared them with the control values. We explored factor combinations (with age as confounder) in the patient group predictive for imbalance with cluster analysis and a machine-learning-based multiple regression method. RESULTS: Sway combined from the four tasks did not differ in the patients and controls on a group level. The combination of the disease duration, the preoperative levodopa responsiveness, and the stimulation responsiveness predicted individual stimulation-induced static imbalance. The more affected patients had more severe motor symptoms; primarily, the proprioceptive followed by visual sensory feedback loss provoked imbalance in them when switching on the stimulation. CONCLUSIONS: The duration of the disease, the severity of motor symptoms, the levodopa responsiveness, and additional sensory deficits should be carefully considered during preoperative evaluation to predict subthalamic stimulation-induced imbalance in Parkinson's disease.

Extracellular Vesicles Derived from Bone Marrow in an Early Stage of Ionizing Radiation Damage Are Able to Induce Bystander Responses in the Bone Marrow.

Ionizing radiation (IR)-induced bystander effects contribute to biological responses to radiation, and extracellular vesicles (EVs) play important roles in mediating these effects. In this study we investigated the role of bone marrow (BM)-derived EVs in the bystander transfer of radiation damage. Mice were irradiated with 0.1Gy, 0.25Gy and 2Gy, EVs were extracted from the BM supernatant 24 h or 3 months after irradiation and injected into bystander mice. Acute effects on directly irradiated or EV-treated mice were investigated after 4 and 24 h, while late effects were investigated 3 months after treatment. The acute effects of EVs on the hematopoietic stem and progenitor cell pools were similar to direct irradiation effects and persisted for up to 3 months, with the hematopoietic stem cells showing the strongest bystander responses. EVs isolated 3 months after irradiation elicited no bystander responses. The level of seven microRNAs (miR-33a-3p, miR-140-3p, miR-152-3p, miR-199a-5p, miR-200c-5p, miR-375-3p and miR-669o-5p) was altered in the EVs isolated 24 hour but not 3 months after irradiation. They regulated pathways highly relevant for the cellular response to IR, indicating their role in EV-mediated bystander responses. In conclusion, we showed that only EVs from an early stage of radiation damage could transmit IR-induced bystander effects.

Oxidative Stress and Gene Expression Modifications Mediated by Extracellular Vesicles: An In Vivo Study of the Radiation-Induced Bystander Effect.

Radiation-induced bystander effect is a biological response in nonirradiated cells receiving signals from cells exposed to ionising radiation. The aim of this in vivo study was to analyse whether extracellular vesicles (EVs) originating from irradiated mice could induce modifications in the redox status and expression of radiation-response genes in bystander mice. C57BL/6 mice were whole-body irradiated with 0.1-Gy and 2-Gy X-rays, and EVs originating from mice irradiated with the same doses were injected into naïve, bystander mice. Lipid peroxidation in the spleen and plasma reactive oxygen metabolite (ROM) levels increased 24 h after irradiation with 2 Gy. The expression of antioxidant enzyme genes and inducible nitric oxide synthase 2 (iNOS2) decreased, while cell cycle arrest-, senescence- and apoptosis-related genes were upregulated after irradiation with 2 Gy. In bystander mice, no significant alterations were observed in lipid peroxidation or in the expression of genes connected to cell cycle arrest, senescence and apoptosis. However, there was a systemic increase in the circulating ROM level after an intravenous EV injection, and EVs originating from 2-Gy-irradiated mice caused a reduced expression of antioxidant enzyme genes and iNOS2 in bystander mice. In conclusion, we showed that ionising radiation-induced alterations in the cellular antioxidant system can be transmitted in vivo in a bystander manner through EVs originating from directly irradiated animals.

The effect of ionising radiation on the phenotype of bone marrow-derived extracellular vesicles.

OBJECTIVES: Ionising radiation-induced alterations affecting intercellular communication in the bone marrow (BM) contribute to the development of haematological pathologies. Extracellular vesicles (EVs), which are membrane-coated particles released by cells, have important roles in intercellular signalling in the BM. Our objective was to investigate the effects of ionising radiation on the phenotype of BM-derived EVs of total-body irradiated mice. METHODS: CBA mice were irradiated with 0.1 Gy or 3 Gy X-rays. BM was isolated from the femur and tibia 24 h after irradiation. EVs were isolated from the BM supernatant. The phenotype of BM cells and EVs was analysed by flow cytometry. RESULTS: The mean size of BM-derived EVs was below 300 nm and was not altered by ionising radiation. Their phenotype was very heterogeneous with EVs carrying either CD29 or CD44 integrins representing the major fraction. High-dose ionising radiation induced a strong rearrangement in the pool of BM-derived EVs which were markedly different from BM cell pool changes. The proportion of CD29 and CD44 integrin-harbouring EVs significantly decreased and the relative proportion of EVs with haematopoietic stem cell or lymphoid progenitor markers increased. Low-dose irradiation had limited effect on EV secretion. CONCLUSIONS: Ionising radiation induced selective changes in the secretion of EVs by the different BM cell subpopulations. ADVANCES IN KNOWLEDGE: The novelty of the paper consists of performing a detailed phenotyping of BM-derived EVs after in vivo irradiation of mice.

Adaptive Radiotherapy for Glioblastoma Multiforme - The Impact on Disease Outcome.

BACKGROUND/AIM: To study the changes of glioblastoma multiforme during chemoradiotherapy (CRT) and to evaluate the impact of changes on dosimetry and clinical outcomes. PATIENTS AND METHODS: Forty-three patients underwent volumetric imaging-based replanning. Prognostic factors and gross tumor volume changes in relation to overall survival and the effect of adaptive replanning were statistically analyzed. RESULTS: Patients with total tumor removal, with shorter time to CRT (<27 days), with methylated O-6 methylguanine DNA methyltransferase and good performance status (>60%) had better survival. Tumor shrinkage in 24 patients resulted in improved survival compared to 19 in whom tumor was unchanged or progressed (25.3 vs. 11.1 months, p=0.04). Adapted planning target volume allowed a reduction in irradiated volume, while increasing survival (12.06 vs. 28.98 months, p=0.026). CONCLUSION: Tumor response during CRT has significant impact on the outcome. Adaptation of the planning target volume to the tumor changes proved to be beneficial and warrants further investigation.

Mitochondrial DNA damage in the hair bulb: can it be used as a noninvasive biomarker of local exposure to low LET ionizing radiation?

Purpose: Our aim was to evaluate whether mitochondrial DNA (mtDNA) damage in hair bulbs could be a suitable biomarker for the detection of local exposure to ionizing radiation.Materials and methods: Mouse hair was collected 4 and 24 hours, 3 and 10 days after single whole-body exposure to 0, 0.1, and 2 Gy radiation. Pubic hair (treated area) and scalp hair (control area) were collected from 13 prostate cancer patients before and after fractioned radiotherapy with an average total dose of 2.7 Gy to follicles after five fractions. Unspecified lesion frequency of mtDNA was analyzed with long PCR, large mtDNA deletion levels were tested with real-time PCR.Results: Unspecified lesion frequency of mtDNA significantly increased in mouse hair 24 hours after irradiation with 2 Gy, but variance among samples was high. No increase in lesion frequency could be detected after 0.1 Gy irradiation. In prostate cancer patients, there was no significant change in either the unspecified lesion frequency or in the proportion of 4934-bp deleted mtDNA in pubic hair after radiotherapy. The proportions of murine 3860-bp common deletion, human 4977-bp common deletion and 7455-bp deleted mtDNA were too low to be analyzed reliably.Conclusions: Our results suggest that the unspecified lesion frequency and proportion of large deletions of mtDNA in hair bulbs are not suitable biomarkers of exposure to ionizing radiation.

Radiofrequency facet joint denervation efficiency based on the severity of spondylarthrosis and in osteoporotic vertebral compression fractures. A retrospective study.

OBJECTIVES: Radiofrequency denervation of the facet joints is performed via a well-established method. Its primary, direct indication is a positive response to a nerve block injection (MBB). Our study aimed to find other, effective but indirect indication signs through the retrospective analysis of our patients treated earlier. PATIENTS AND METHODS: In our institute between 1 January, 2008 and 31 December, 2017 facet joint denervation has been performed in more than 2000 cases, and we included 529 patients in our retrospective study. We had separate groups for vertebral compression fractures and for spondylarthrosis of different severity (Grade 1; 2-3; 4), thus we assessed the postoperative condition of these patients using Visual Analoge Scale (VAS). The efficacy of the intervention was examined in every groups separately according to symptoms and previous spine surgeries. RESULTS: In view of our results, chronic lumbago and dorsalgia that are attributable to osteoporotic vertebral compression fracture are obvious indications if they do not respond to conservative therapy, as 76.8% of such patients remained asymptomatic for minimum 6 months (p = 0,000). Another indication is Grade 2 or 3 chronic spondylarthrosis without radicular involvement, since these groups reported a 51.4% success rate (asymptomatic for minimum 6 months) (p = 0,015). Long term pain relief is obviously impaired by the presence of radicular compression, as we were not able to decrease the pain of 97% of such patients. Our findings also suggest that the vast majority of those who have previously undergone spine surgery cannot benefit from the intervention. CONCLUSION: Based on this study, facet joint denervation can serve as an effective therapy supplement in a properly selected group of patients who do not respond to oral NSAIDs, exercise and physiotherapy. By this procedure we found we can reach long term benefit in the groups of osteoporotic vertebral fracture patients and patients with moderate spondylarthrosis. According to our results and the literature datas the properly patient selection for the indication of the RF ablation can be as effective as the controversial diagnostic nerve block injections.

Slit Ventricle as a Neurosurgical Emergency: Case Report and Review of Literature.

BACKGROUND: Symptomatic slit ventricle is one of the most challenging complications of shunt surgery in children. Clinical signs and symptoms may appear with a wide range of intracranial pressure (ICP) values. We report the case of a 10-year-old girl, who did not present the classic clinical features of extremely elevated ICP, which was proven by multiple invasive ICP recordings, performed during shunt revisions. CASE DESCRIPTION: At the age of 6 months, the patient presented squeal for many hours, accompanied with sunset eyes, bulging anterior fontanel, and dilated ventricles of all 4 ventricles on computed tomography scan. Acute ventriculoperitoneal shunt insertion was performed with adjustable valve. During the following 9 years, she was regularly seen and medically treated for intermittent headache, with nausea and vomiting. From 9 years of age, she was hospitalized for severe (10/10 on the visual analog scale), unbearable headache, agitation, and screaming on multiple occasions. Altogether, we had to revise the shunt system 5 times throughout 1 year. Radiologic imaging always showed narrow ventricles. Ophthalmologic examination of the fundus never revealed signs of raised ICP. Perioperative monitoring of the ICP with intraparenchymal sensor showed unexpected high values of 40-45 mm Hg. However, repetitive shunt revisions were successful only temporarily because the symptoms always returned. Only bilateral shunting of the ventricular system was able to eliminate the symptoms permanently. CONCLUSIONS: Images of slit ventricle can be associated either with low or extremely high ICP needing urgent surgical consideration, including ICP monitoring. Bilateral shunt insertion can be effective treatment for slit ventricle syndrome.

Connectivity-based segmentation of the brainstem by probabilistic tractography.

Diffusion magnetic resonance imaging is a non-invasive tool increasingly used for the investigation of brain connectivity in vivo. In this paper we propose a method that allows segmentation of the brainstem to four subregions (frontopontine, motor, sensory and reticular) based on connections to supratentorial structures, thereby eliminating the need for using anatomical landmarks within the brainstem for the identification of these subregions. The feasibility of connectivity-based brainstem segmentation was investigated in a group of healthy subjects (n = 20). Multifiber probabilistic tractography was performed using the FMRIB Software Library, and connections between a pontomesencephalic seed mask and four supratentorial target regions (anterior and posterior limbs of the internal capsule, sensory and medial thalamus) were used to determine connectivity maps of the brainstem. Results were compared with a neuroanatomy atlas and histological sections, confirming good anatomic correspondence. The four subregions detected by the connectivity-based segmentation showed good intersubject reproducibility. The presented method may be a potential tool to investigate brainstem connectivity in diseases that distort normal anatomy, and quantitative analyses of the diffusion-related parameters may provide additional information on the involvement of brainstem pathways in certain disease states (e.g., traumatic brain injury, demyelinating disorders, brainstem tumors). The potential clinical applicability of the method is demonstrated in two cases of severe traumatic brain injury.

Extracellular Vesicles Mediate Radiation-Induced Systemic Bystander Signals in the Bone Marrow and Spleen.

Radiation-induced bystander effects refer to the induction of biological changes in cells not directly hit by radiation implying that the number of cells affected by radiation is larger than the actual number of irradiated cells. Recent in vitro studies suggest the role of extracellular vesicles (EVs) in mediating radiation-induced bystander signals, but in vivo investigations are still lacking. Here, we report an in vivo study investigating the role of EVs in mediating radiation effects. C57BL/6 mice were total-body irradiated with X-rays (0.1, 0.25, 2 Gy), and 24 h later, EVs were isolated from the bone marrow (BM) and were intravenously injected into unirradiated (so-called bystander) animals. EV-induced systemic effects were compared to radiation effects in the directly irradiated animals. Similar to direct radiation, EVs from irradiated mice induced complex DNA damage in EV-recipient animals, manifested in an increased level of chromosomal aberrations and the activation of the DNA damage response. However, while DNA damage after direct irradiation increased with the dose, EV-induced effects peaked at lower doses. A significantly reduced hematopoietic stem cell pool in the BM as well as CD4+ and CD8+ lymphocyte pool in the spleen was detected in mice injected with EVs isolated from animals irradiated with 2 Gy. These EV-induced alterations were comparable to changes present in the directly irradiated mice. The pool of TLR4-expressing dendritic cells was different in the directly irradiated mice, where it increased after 2 Gy and in the EV-recipient animals, where it strongly decreased in a dose-independent manner. A panel of eight differentially expressed microRNAs (miRNA) was identified in the EVs originating from both low- and high-dose-irradiated mice, with a predicted involvement in pathways related to DNA damage repair, hematopoietic, and immune system regulation, suggesting a direct involvement of these pathways in mediating radiation-induced systemic effects. In conclusion, we proved the role of EVs in transmitting certain radiation effects, identified miRNAs carried by EVs potentially responsible for these effects, and showed that the pattern of changes was often different in the directly irradiated and EV-recipient bystander mice, suggesting different mechanisms.

Effect of subthalamic stimulation on distal and proximal upper limb movements in Parkinson's disease.

INTRODUCTION: A different innervation pattern of proximal and distal muscles from the contra- and ipsilateral motor circuits raises the question as to whether bilateral, contra- and ipsilateral subthalamic stimulation may have different effects on the distal and proximal movements of the upper limb. To answer this question, we performed kinematic analyzes in patients with Parkinson's disease. METHODS: Twenty-eight Parkinsonian patients treated by bilateral subthalamic stimulation were examined with an age-matched control group of 28 healthy subjects. They performed 14s of finger tapping, hand grasping and pronation-supination. The patient group performed these sessions in four conditions (BOTH ON, BOTH OFF, CONTRA ON, IPSI ON) after withdrawal of dopaminergic medication for 12h and a fifth condition after taking medication (BOTH ON-MED ON). A motion sensor with a three-dimensional gyroscope was worn on the index finger. Speed, amplitude, rhythm and decrement of movements were calculated and compared across these conditions. RESULTS: Speed and amplitude of the more distal movements were improved similarly by contra- and bilateral stimulation. Bilateral stimulation was more effective than contralateral stimulation for the more proximal movements. Contra- and bilateral stimulation ameliorated the rhythm similarly in each movement task. Decrement of distal and proximal movements was not affected by the stimulation conditions. CONCLUSION: This is the first study to show that the outcome of bi- and unilateral subthalamic stimulation on proximal and distal upper limb movements should be evaluated separately postulating the different somatotopic organization of subloops in the cortico-basal ganglia motor circuits.

The role of probabilistic tractography in the surgical treatment of thalamic gliomas.

BACKGROUND: Thalamic gliomas represent a great challenge for neurosurgeons because of the high surgical risk of damaging the surrounding anatomy. Preoperative planning may considerably help the surgeon find the most ideal operative trajectory, avoiding thalamic nuclei and important white matter pathways adjacent to the tumor tissue. Thalamic segmentation is a promising imaging tool based on diffusion tensor magnetic resonance imaging. It provides the possibility to predict the relationship of the tumor to thalamic nuclei. OBJECTIVE: To propose a new tool in thalamic glioma surgery that may help to differentiate between normal thalamus and tumor tissue, making preoperative planning possible and facilitating the choice of the optimal surgical approach and trajectory for neuronavigation-assisted surgery. METHODS: Four patients with thalamic gliomas preoperatively underwent conventional and diffusion-weighted magnetic resonance imaging conducted on 1.5 T. Subsequently, probabilistic tractography and thalamic segmentation were performed with the FSL Software as preoperative planning. We also present a case when thalamic segmentation was applied retrospectively using preoperative images. All patients went through neuronavigation-assisted surgery (1 partial, 4 subtotal resections). RESULTS: Surgery performed based on the output of thalamic segmentation caused no deterioration in the neurological symptoms of our patients. Indeed, we noticed improvement in the neurological condition in 3 cases; furthermore, in 2 patients, a concern-free state was achieved. CONCLUSION: We suggest that thalamic segmentation may be applied successfully and routinely in the surgical treatment of thalamic gliomas.

PACAP and VIP differentially preserve neurovascular reactivity after global cerebral ischemia in newborn pigs.

Pituitary adenylate cyclase activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) are neuroprotective in numerous models. Impairment of cerebrovascular reactivity (CR) contributes to ischemia/reperfusion (I/R)-induced neuronal damage. We tested whether PACAP and/or VIP preserve CR to I/R-sensitive dilator responses dependent on endothelial and/or neuronal function. Accordingly, changes in pial arteriolar diameters in response to hypercapnia (5-10% CO(2) ventilation) or topical N-methyl-d-aspartate (NMDA, 10(-4) M) were determined before and after I/R via intravital microscopy in anesthetized/ventilated piglets. Local pretreatment with non-vasoactive doses of PACAP (10(-8) M) and VIP (10(-9) M) prevented the attenuation of postischemic CR to hypercapnia; to 10% CO(2), the CR values were 27+/-8% vs 92+/-5% vs 88+/-13% (vehicle vs PACAP38 vs VIP, CR expressed as a percentage of the response before I/R, mean+/-SEM, n=8-8, p<0.05). PACAP, but not VIP, preserved CR to NMDA after I/R, with CR values of 31+/-10% vs 87+/-8% vs 35+/-12% (vehicle vs PACAP38 vs VIP, n=6-6). Unlike PACAP, VIP-induced vasodilation has not yet been investigated in the piglet. We tested whether VIP-induced arteriolar dilation was sensitive to inhibitors of cyclooxygenase (COX)-1 (SC-560, 1 mg/kg), COX-2 (NS-398, 1 mg/kg), indomethacin (5 mg/kg), and nitric oxide synthase (L-NAME, 15 mg/kg). VIP (10(-8)-10(-7)-10(-6) M, n=8) induced reproducible, dose-dependent vasodilation of 16+/-3%, 33+/-6%, and 70+/-8%. The response was unaffected by all drugs, except that the vasodilation to 10(-8) M VIP was abolished by SC-560 and indomethacin. In conclusion, PACAP and VIP differentially preserve postischemic CR; independent of their vasodilatory effect.