Publications by authors named "Jan Michel"

Ion computed tomography (iCT) is an imaging modality for the direct determination of the relative stopping power (RSP) distribution within a patient's body. Usually, this is done by estimating the path and energy loss of ions traversing the scanned volume utilising a tracking system and a separate residual energy detector. This study, on the other hand, introduces the first experimental study of a novel iCT approach based on time-of-flight (TOF) measurements, the so-called Sandwich TOF-iCT concept, which in contrast to any other iCT systems, does not require a residual energy detector for the RSP determination.

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Article Synopsis
  • * The ASPEN study compared zanubrutinib with ibrutinib in patients with the MYD88 mutation and included a separate group of MYD88WT patients receiving only zanubrutinib.
  • * In the MYD88WT cohort of 26 patients, 27% achieved a very good partial response, and overall survival rates at 18 months were 88%, indicating that zanubrutinib could be an effective treatment for this patient group despite
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According to the World Health Organization classification of pituitary tumors, only tumors with systemic metastasis must be considered as carcinomas. Invasive tumors with multiple recurrences are only classified as aggressive tumors or "atypical adenomas". To illustrate the problems encountered in the pathological diagnosis of pituitary carcinoma and in patient management, we present two male patients operated on for an aggressive prolactin pituitary adenoma with and without metastasis.

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Von Hippel-Lindau disease is an autosomal dominant disorder involving the development of specific tumours in multiple organs, both benign and malignant. In the CNS, the syndrome is characterized by haemangioblastomas of the retina, spinal cord and brain. We report the case of a 15-year-old boy with the diagnosis of aggressive GH-PRL pituitary macroadenoma and a family history of VHL disease.

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Seeding on surgical pathway is a rare form of clival chordoma treatment failure. We report the case of a 42-year-old male with a clival chondroid chordoma removed by a sublabial transsphenoidal approach followed by proton beam radiotherapy, who developed a maxillary bone recurrence 3 years after surgery.

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c-Yes, a member of the Src tyrosine kinase family, is found highly activated in colon carcinoma but its importance relative to c-Src has remained unclear. Here we show that, in HT29 colon carcinoma cells, silencing of c-Yes, but not of c-Src, selectively leads to an increase of cell clustering associated with a localisation of β-catenin at cell membranes and a reduction of expression of β-catenin target genes. c-Yes silencing induced an increase in apoptosis, inhibition of growth in soft-agar and in mouse xenografts, inhibition of cell migration and loss of the capacity to generate liver metastases in mice.

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This study investigated the interactions of supraspinal with spinal neuronal circuits during obstacle steps by recordings of electroencephalography (EEG), reflex activity and limb muscle electromyography (EMG). Subjects walking with reduced vision on a treadmill were acoustically informed about an approaching obstacle and received feedback about task performance. Only following a task-relevant acoustic signal, spinal reflex responses, evoked by tibial nerve stimulation during mid-stance, were enhanced in proximal arm and leg flexor muscles prior to obstacle compared to normal swing, reflecting the neuronal preparation of the task.

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To evaluate a potential association of REM-sleep behavior disorder (RBD) with gait and postural impairment in Parkinson's disease (PD). Gait difficulties and postural impairment are frequent in PD and are a major cause of disability. Animal studies indicate a key role of the pedunculopontine nucleus (PPN) in gait, postural control, and REM sleep, and also in the pathophysiology of RBD.

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We present three cases of meningiomas developing at the site of an old head trauma. We then review the literature regarding the controversies on the development of post-traumatic brain tumors and, finally, we emphasize the medico-legal characteristics of post-traumatic meningiomas, particularly with respect to their cell type which is frequently atypical or anaplastic and which have a poor outcome.

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Aims: Clear cell meningioma (CCM) is a rare variant of meningioma, which is important to distinguish because of its aggressive behaviour. Sixty-eight cases have been previously described in the literature. In this retrospective study, we report seven cases of CCM operated in our institution between 1994 and 2008.

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Objective: Pontine cavernomas are benign vascular lesions whose surgical treatment is challenging due to their localization. We report our experience in the surgical management of these lesions exclusively using a lateral, subtemporal transtentorial approach in high pontine lesions and an anterior petrosal approach in low pontine lesions.

Methods: We performed a retrospective study on a series of patients who were operated on for a pontine cavernoma in our neurosurgery department between 1987 and 2007.

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Context And Objective: Predicting pituitary tumor behavior remains a challenge. This multiparameter investigation aimed to identify markers for recurrence and progression in prolactin tumors.

Design: From a cohort of patients treated for prolactin tumors by surgery, we retrospectively studied clinical data, tumor characteristics, clinical outcome, and the expression of nine genes by quantitative RT-PCR.

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Angiolipomas are rare tumors of the CNS that most frequently develop in the orbit, the cavernous space, and the epidural space of the spine. The authors report the case of a patient who presented with an angiolipoma of the cavernous space. Using data from the published literature and an experimental anatomical approach, they demonstrate that the cavernous space contains adipose tissue.

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Object: The dura mater has 2 dural layers: the endosteal layer (outer layer), which is firmly attached to the bone, and the meningeal layer (inner layer), which directly covers the brain. These 2 dural layers join together in the middle temporal fossa or the convexity and separate into the orbital, lateral sellar compartment (LSC), or spinal epidural space to form the extradural neural axis compartment (EDNAC). The aim of this work was to anatomically verify the concept of the EDNAC by using electron microscopy.

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During evolution, the increased influence of a direct cortical-motoneuronal system in parallel with a more specialized hand function might have replaced phylogenetically older systems that organized locomotor movements. However, recent research indicates that interlimb coordination during human locomotion is organized in a way similar to that in the cat. During locomotion, corticospinal excitation of upper-limb motoneurons is mediated indirectly, via propriospinal neurons in the cervical spinal cord.

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Patients with Parkinson's disease (PD) have difficulties in performing complex bimanual movements. Here we have examined acquisition and performance of a bilateral obstacle stepping task to see whether these difficulties are also present during bipedal movements. Subjects had to minimize foot clearance when repeatedly stepping on a treadmill over randomly approaching obstacles on either side.

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Although most pituitary tumors are benign, some are invasive or aggressive. In the absence of specific markers of malignancy, only tumors with metastases are considered malignant. To identify markers of invasion and aggressiveness, we focused on prolactin (PRL) tumors in the human and rat.

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Purpose: To prospectively assess health-related quality of life (HR-QoL) in women after conserving surgery for breast cancer during/after postoperative 3-D radiotherapy.

Patients And Methods: 109 consecutively treated patients were analyzed. HR-QoL was assessed at initiation (t1), end (t2), and 6 weeks after radiotherapy (t3) using the EORTC modules QLQ-C30/BR23.

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Object: Pituitary adenomas are usually benign tumors; however, some behave aggressively and metastasize. Until now, no specific marker of aggressive behavior or malignancy has been found. The polysialylated neural cell adhesion molecule (NCAM), which is highly expressed in embryonic tissues such as the brain and pituitary, is detected in some and neuroendocrine tumors.

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