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P Wesseling

Publications and source records attributed to P Wesseling.

At least 19 recordsLinked to original sources
PubMed2006

Giant cavernous hemangiomas: report of three cases.

Giant cavernous hemangiomas occur very rarely, and little has been reported about their behavior. In this case report three cavernous hemangiomas with a diametric measure between 6 cm and 7 cm and distinct features will be described. A 36-year-old female patient presented with headache and nausea. A CT scan disclosed a large circumscribed tumor with strong contrast enhancement in the temporo-parieto-occipital region of the right cerebral hemisphere and extension into the right cerebellar hemisphere. A 35-year-old woman was admitted to our emergency ward with a generalized seizure and a dilated pupil. The CT scan showed an extensive left frontal lesion containing a substantial hyperintense part, suspicious for hemorrhage. A 3-year-old girl was admitted with generalized seizure and progressively declining consciousness. A large left frontotemporal paraventricular multi-cystic lesion was encountered on the CT scan. All three patients were operated on. Two recovered very well. In the case of the 3-year-old girl stable disease was reached. Giant cavernomas do not differ from average-sized cavernomas in clinical, surgical or histopathological presentation but may differ radiologically. However, the possible diagnosis of cavernoma can be overlooked, due to their size and possible differential diagnosis.

Adult↗
PubMed2006

Virilization due to ovarian androgen hypersecretion in a patient with ectopic adrenocorticotrophic hormone secretion caused by a carcinoid tumour: case report.

A 52-year-old woman presented with symptoms of virilization, which had been ongoing for 5 months. At the age of 34 years, she had a large abdominal carcinoid tumour removed. Twelve years later, she presented with Cushing's syndrome due to ectopic adrenocorticotrophic hormone (ACTH) production by carcinoid metastases localized in the right parametrium, fornix posterior and right diaphragm. Debulking laparotomy was performed followed by remission of hypercortisolism. Relapse of hypercortisolism followed 3 years later, and a second debulking laparotomy was performed including resection of the right ovary. In the following year, relapses of hypercortisolism were observed until bilateral adrenalectomy was performed. Laboratory evaluation revealed elevated serum levels of testosterone (23.0 nmol/l), androstenedione and 17-hydroxyprogesterone, and a serum estradiol (E2) level in the premenopausal range. The computerized tomography (CT) of the abdomen showed a large pelvic mass on the left side of the uterus without a recognizable left ovary. Treatment with a GnRH agonist (goserelin, 3.6 mg s.c., monthly) was initiated, resulting in normalization of the androgen levels. One year later, obstruction of the right ureter occurred due to progression of the pelvic metastases, thus a third debulking laparotomy with resection of the pelvic metastases including the left ovary was performed. The microscopic examination of the removed pelvic mass showed malignant carcinoid tissue with focal remnants of atrophic ovarian tissue. Two years after surgery, serum androgen levels are undetectable. We hypothesize that the high levels of ACTH at the site of the left ovary have induced androgen hypersecretion by steroid-producing cells in the ovary of our patient.

Adrenocortical Hyperfunction↗
PubMed2006

A patient with recurrent hypercortisolism after removal of an ACTH-secreting pituitary adenoma due to an adrenal macronodule.

A 41-yr-old female was referred for signs and symptoms of Cushing's syndrome. Cortisol was not suppressed by 1 mg dexamethasone (0.41 micromol/l). Midnight cortisol and ACTH were 0.44 micromol/l and 18 pmol/l, respectively. Urinary cortisol excretion was 250 nmol/24 h (normal between 30 and 150 nmol/24 h). A magnetic resonance imaging (MRI) revealed a pituitary lesion of 7 mm. ACTH and cortisol levels were unaltered by administration of human CRH and high-dose dexamethasone. Inferior sinus petrosus sampling showed CRH-stimulated ACTH levels of 128.4 (left sinus) vs a peripheral level of 19.2 pmol/l, indicating Cushing's disease. After 4 months of pre-treatment with metyrapone and dexamethasone, endoscopic transsphenoidal resection of an ACTH-positive pituitary adenoma was performed. ACTH levels decreased to 2.6 pmol/l and fasting cortisol was 0.35 micromol/l. Despite clinical regression of Cushing's syndrome and normalization of urinary cortisol, cortisol was not suppressed by 1 mg dexamethasone (0.30 micromol/l). Ten months post-operatively, signs and symptoms of Cushing's syndrome reoccurred. A high dose dexamethasone test according to Liddle resulted in undetectable ACTH, but no suppression of cortisol levels, pointing towards adrenal-dependent Cushing's syndrome. Computed tomography (CT)-scanning showed a left-sided adrenal macronodule. Laparoscopic left adrenalectomy revealed a cortical macronodule (3.5 cm) surrounded by micronodular hyperplasia. Fasting cortisol had decreased to 0.02 micromol/l. Glucocorticoid suppletion was started and tapered over 12 months. Symptoms and signs of hypercortisolism gradually disappeared. This case illustrates, that longstanding ACTH stimulation by a pituitary adenoma can induce unilateral macronodular adrenal hyperplasia with autonomous cortisol production.

ACTH-Secreting Pituitary Adenoma↗
PubMed2006

Specific association of small heat shock proteins with the pathological hallmarks of Alzheimer's disease brains.

The small heat shock protein family (sHsp) comprises molecular chaperones able to interact with incorrectly folded proteins. Alzheimer's disease (AD) is characterized by pathological lesions such as senile plaques (SPs), cerebral amyloid angiopathy (CAA) and neurofibrillary tangles (NFTs), predominantly consisting of the incorrectly folded proteins amyloid-beta (Abeta) and tau respectively. The aim of this study was to investigate the association of the chaperones Hsp20, HspB2, alphaB-crystallin and Hsp27 with the pathological lesions of AD brains. For this purpose, a panel of well-characterized antibodies directed against these sHsps was used in immunohistochemistry and immunoblotting. We observed extracellular expression of Hsp20, Hsp27 and HspB2 in classic SPs, and Hsp20 expression in diffuse SPs. In addition, extracellular expression of HspB2 was observed in CAA. Both Hsp27 and alphaB-crystallin were also observed in astrocytes associated with both SPs and CAA. Furthermore, none of the sHsps were observed in NFTs in AD brains. We conclude that specific sHsp species may be involved in the pathogenesis of either SPs or CAA in AD.

Aged↗
PubMed2005

Three-dimensional reconstruction of tumor microvasculature: simultaneous visualization of multiple components in paraffin-embedded tissue.

Three-dimensional (3D) visualization of microscopic structures may provide useful information about the exact 3D configuration, and offers a useful tool to examine the spatial relationship between different components in tissues. A promising field for 3D investigation is the microvascular architecture in normal and pathological tissue, especially because pathological angiogenesis plays a key role in tumor growth and metastasis formation. This paper describes an improved method for 3D reconstruction of microvessels and other microscopic structures in transmitted light microscopy. Serial tissue sections were stained for the endothelial marker CD34 to highlight microvessels and corresponding images were selected and aligned. Alignment of stored images was further improved by automated non-rigid image registration, and automated segmentation of microvessels was performed. Using this technique, 3D reconstructions were produced of the vasculature of the normal brain. Also, to illustrate the complexity of tumor vasculature, 3D reconstructions of two brain tumors were performed: a hemangioblastoma and a glioblastoma multiforme. The possibility of multiple component visualization was shown in a 3D reconstruction of endothelium and pericytes of normal cerebellar cortex and a hemangioblastoma using alternate staining for CD34 and alpha-smooth muscle actin in serial sections, and of a GBM using immunohistochemical double staining. In conclusion, the described 3D reconstruction procedure provides a promising tool for simultaneous visualization of microscopic structures.

Brain Neoplasms↗
PubMed2004

Mapping of the SCA23 locus involved in autosomal dominant cerebellar ataxia to chromosome region 20p13-12.3.

We report upon a Dutch autosomal dominant cerebellar ataxia (ADCA) family, clinically characterized by a late-onset (>40 years), slowly progressive, isolated spinocerebellar ataxia (SCA). Neuropathological examination in one affected subject showed neuronal loss in the Purkinje cell layer, dentate nuclei and inferior olives, thinning of cerebellopontine tracts, demyelination of posterior and lateral columns in the spinal cord, as well as ubiquitin-positive intranuclear inclusions in nigral neurons that were considered to be Marinesco bodies. Data obtained from the genome-wide linkage analysis revealed a maximal lod score of 3.46 at = 0.00 for marker D20S199. This new SCA locus, on chromosome region 20p13-p12.3, was designated SCA23 after approval by the HUGO Nomenclature Committee. Currently, candidate genes are being screened for mutations within the SCA23 interval. In addition to the recently identified SCA14, SCA19 and FGF14 families, SCA23 is yet another novel SCA locus in the Dutch ADCA population, which further defines the genetic heterogeneity of ADCA families in the Netherlands.

Adult↗
PubMed2004

Development and malformations of the human pyramidal tract.

The corticospinal tract develops over a rather long period of time, during which malformations involving this main central motor pathway may occur. In rodents, the spinal outgrowth of the corticospinal tract occurs entirely postnatally, but in primates largely prenatally. In mice, an increasing number of genes have been found to play a role during the development of the pyramidal tract. In experimentally studied mammals, initially a much larger part of the cerebral cortex sends axons to the spinal cord, and the site of termination of corticospinal fibers in the spinal grey matter is much more extensive than in adult animals. Selective elimination of the transient corticospinal projections yields the mature projections functionally appropriate for the pyramidal tract. Direct corticomotoneuronal projections arise as the latest components of the corticospinal system. The subsequent myelination of the pyramidal tract is a slow process, taking place over a considerable period of time. Available data suggest that in man the pyramidal tract develops in a similar way. Several variations in the funicular trajectory of the human pyramidal tract have been described in otherwise normally developed cases, the most obvious being those with uncrossed pyramidal tracts. A survey of the neuropathological and clinical literature, illustrated with autopsy cases, reveals that the pyramidal tract may be involved in a large number of developmental disorders. Most of these malformations form part of a broad spectrum, ranging from disorders of patterning, neurogenesis and neuronal migration of the cerebral cortex to hypoxic-ischemic injury of the white matter. In some cases, pyramidal tract malformations may be due to abnormal axon guidance mechanisms. The molecular nature of such disorders is only beginning to be revealed.

Animals↗
PubMed2004

Inverse correlation between genetic aberrations and malignancy grade in ependymal tumors: a paradox?

OBJECTIVE: The goal of our study was to investigate the inverse correlation between number of genetic aberrations and malignancy grade in ependymal tumors at the ploidy level. METHODS: we examined seven myxopapillary ependymomas (mpEs) (WHO grade I), 28 spinal and cerebral ependymomas (Es) (WHO grade II), and 18 cerebral anaplastic ependymomas (aEs) (WHO grade III) using image DNA cytometry. The ploidy status was correlated with clinicopathological characteristics and with the results obtained by comparative genomic hybridization (CGH) analysis that we performed in about half of these tumors. RESULTS: mpEs were exclusively located in the spinal cord and aEs in the cerebrum only, whereas Es were located in both the spinal cord and brain. We found aneuploidy or tetraploidy to be common in the group of mpEs (6 out of 7) and much less frequent in Es (6 out of 28) and aEs (4 out of 18). Three-year postoperative survival was 100% for mpEs, 100% for spinal Es, 92% for cerebral Es, and 33% for aEs. Our CGH results in a selection of these tumors revealed the highest number of genetic aberrations in the mpEs (average 16; n = 2), a lower number in Es (average 12; n = 11) and the lowest number in aEs (average 5; n = 6). Interestingly, in the group of Es and aEs, a high number of genetic aberrations as detected by CGH was not correlated with aneuploidy or tetraploidy. Three patients, all with mpEs had local seeding. CONCLUSION: These results underline that mpEs are distinctly different from Es and aEs at the genetic level and that extensive genomic alterations and aneuploidy in ependymal tumors are not in itself an indicator of malignant behavior.

Adolescent↗
PubMed2004

Differential patterns of insulin-like growth factor-I and -II mRNA expression in medulloblastoma.

Insulin-like growth factors (IGFs) play an important role in tumour growth and development. We hypothesized that this is also the case for medulloblastomas, which are highly malignant cerebellar brain tumours usually occurring in children. In these tumours the expression patterns of IGF-I and -II mRNA were studied. Tumour specimens obtained from 12 children and two adults at diagnosis were hybridized in situ with digoxigenin-labelled cRNA probes for hIGF-I and hIGF-II mRNAs. In all cases, tumour cells showed abundant expression of IGF-I mRNA. Nine of the 14 tumours showed variable but significant IGF-II expression. In these tumours, the hybridization signal almost exclusively colocalized with a subpopulation of Ki-M1P positive cells that were identified as ramified microglia (RM) cells. In the five tumours without IGF-II expression, microglia/brain macrophages with a more rounded amoeboid-like morphology predominated. RM cells in normal cerebellar tissues, residing abundantly in areas of the white and, to a less extent, in the grey matter, were IGF-II mRNA-negative. These RM cells showed a thinner and more extensively branched appearance and were more evenly distributed than those encountered in medulloblastoma. Probably, during the transformation from the resting ramified towards the amoeboid morphology (or vice versa) IGF-II mRNA expression is only temporarily induced. The physiological meaning of the induction of IGF-II mRNA expression by these cells in medulloblastoma remains unclear but any IGF-II peptide synthesized could exert unfavourable mitogenic and antiapoptotic effects on adjacent tumour cells. However, in this relatively small number of cases we could not find any indications for a relationship between clinical characteristics of the various cases and the extent of IGF-II mRNA expression.

Adult↗
PubMed2004

Massive reduction of tumour load and normalisation of hyperprolactinaemia after high dose cabergoline in metastasised prolactinoma causing thoracic syringomyelia.

In 1970 a 20 year old woman presented with a pituitary chromophobe adenoma for which she underwent transfrontal pituitary surgery. In 1978 she had to be reoperated on because of local tumour recurrence, resulting in hypopituitarism. Bromocriptine (5 mg/day) was given for 15 years, but the plasma prolactin levels remained elevated. In 2000 the patient presented with signs and symptoms suggestive of a spinal cord lesion at the mid-thoracic level. A magnetic resonance imaging (MRI) scan showed an extensive leptomeningeal mass extending from the brainstem to L5, with a thoracic syringomyelia at the T7-T8 level. The plasma prolactin level was very high (5114 microg/l). A biopsy showed the presence of a metastasised prolactinoma. On administration of high dose cabergoline, 0.5 mg twice a day orally, the plasma prolactin levels decreased within one month and then normalised within 26 months. Tumour load reduced considerably but unfortunately, her signs and symptoms did not improve. This case illustrates that a high dose dopamine agonist might be an important therapeutic option in patients with a metastasised prolactinoma.

Adult↗
PubMed2003

Development and developmental disorders of the human cerebellum.

The human cerebellum develops over a long time, extending from the early embryonic period until the first postnatal years. This protracted development makes the cerebellum vulnerable to a broad spectrum of developmental disorders. The development of the cerebellum occurs in four basic steps: 1) characterization of the cerebellar territory at the midbrain-hindbrain boundary; 2) formation of two compartments for cell proliferation: first, the Purkinje cells and the deep cerebellar nuclei arise from the ventricular zone of the metencephalic alar plate; second, granule cell precursors are formed from a second compartment of proliferation, i. e. the upper rhombic lip; 3) inward migration of the granule cells: granule precursor cells form the external granular layer, from which (and continuing into the first postnatal year), granule cells migrate inwards to their definite position in the internal granular layer, and 4) formation of cerebellar circuitry and further differentiation. The precerebellar nuclei, i. e. the pontine nuclei and the inferior olive, arise from the lower rhombic lip. Developmental disorders of the cerebellum are often accompanied by malformations of the precerebellar nuclei. In this review the development of the cerebellum and some of its more frequent developmental disorders, such as the Dandy-Walker and related midline malformations, and the pontocerebellar hypoplasias, are discussed.

Cerebellar Diseases↗
PubMed2002

A spinal intradural enterogenous cyst with well-differentiated muscularis propria.

We report a case of a newborn presenting with severe compression of the spinal cord due to a large, solitary mass extending from C4 to T2. Neurosurgical exploration revealed a large intradural, extramedullary cystic lesion, compressing the spinal cord. Slowly progressive respiratory failure due to severe myelopathy led to the death of the child 19 days postpartum. At autopsy, a well-differentiated enterogenous cyst was found, the cyst wall containing gastric and esophageal type mucosa, and a bona fide muscularis propria. The gastrointestinal tract was completely normal. The possible developmental history of intradural enterogenous cysts is discussed.

Cervical Vertebrae↗
PubMed2002

Neuropathological diagnostic accuracy.

This study investigated variations in neuropathological diagnosis when histopathological slides are evaluated with access to all information pertinent to a case, compared with evaluation of H & E stained slides with only limited clinical information. The aim of the study is to evaluate the role of 'local' factors in reaching a definitive, neuropathological diagnosis. Each of 227 cases was reviewed by the local neuropathologist at one of three European centres with access to all clinical, radiological and histopathological data. Each case was also reviewed by a second, independent neuropathologist at another European unit, who was blinded to the local pathologist's diagnosis, and only had access to the age and sex of the patient and the location of the lesion. For the histopathological evaluation, initially he had access to H & E and GFAP stains only. Diagnoses were made using the WHO 2000 classification system and the two evaluations were classified into one of the following four categories: complete agreement; minor disagreement (not affecting treatment); minor disagreement (affecting treatment); complete disagreement. In 175 (77.1%) cases there was complete agreement between the two neuropathologists and in 18 (7.9%) cases there were non-treatment altering discrepancies in the diagnoses. Overall, there was disagreement which might potentially affect treatment in 34 (15%) of the cases. Histopathological diagnosis of the majority (85%) of brain tumours is accurate and uniform. However, histopathology is subject to a degree of interpretation. The availability of full, 'local', clinical information may be of considerable importance to the diagnostic process.

Biopsy↗
PubMed2002

Intestinal mucosa on top of a rudimentary occipital meningocele in amniotic rupture sequence: disorganization-like syndrome, homeotic transformation, abnormal surface encounter or endoectodermal adhesion?

We present a case of a peculiar rudimentary occipital meningocele that was surgically removed when the patient (a boy) was 5 months of age. The patient also had distal transverse defects of both hands. The association of congenital scalp defects and distal congenital hand anomalies is relatively rare and one form is known as the Adams-Oliver syndrome. To our surprise, microscopic examination revealed intestinal mucosa on top of the skin tag containing the rudimentary meningocele. No comparable cases were found in the literature. We discuss the following possible explanations for this peculiar situation: 1) disorganization-like syndrome; 2) homeotic transformation; 3) abnormal surface encounter between the epidermis and remnants of the yolk sac or omphalo-enteric duct; and 4) endoectodermal adhesion in the presomite embryo.

Abnormalities, Multiple↗
PubMed2001

The pattern of metastasis of human melanoma to the central nervous system is not influenced by integrin alpha(v)beta(3) expression.

We investigated the effect of integrin alpha(v)beta(3) expression on the metastatic pattern of human melanoma cells in the central nervous system (CNS). For this purpose, we developed a hematogenous CNS melanoma metastasis model in nude mice using a modified internal carotid artery infusion technique. This protocol revealed 2 different patterns of CNS metastasis. The integrin alpha(v)beta(3)-expressing melanoma lines Mel57 and Zkr nearly exclusively produced metastases in the brain parenchyma, whereas cells of the BLM and MV3 lines, devoid of integrin alpha(v)beta(3) expression, preferentially metastasized to dura mater and leptomeninges. Treatment with hyaluronidase to obtain single BLM cell suspensions did not influence the metastatic pattern, indicating that this was not simply the result of entrapment of tumor cell aggregates in large-sized leptomeningeal vessels. The role of integrin alpha(v)beta(3) expression in the process of metastasis was tested by transfection of BLM, but did not lead to an altered pattern of metastasis. We did observe, however, slower growth of the transfected tumors, although the in vitro growth rate was unaltered, indicating a reduction in tumorigenicity. We conclude from our findings that CNS metastasis of melanoma cells in the mouse xenograft model occurs in at least 2 different but very reproducible patterns. Although it is predicted that adhesion of tumor cells to endothelial cells plays a role in this phenomenon, tumor cell integrin alpha(v)beta(3) expression per se does not explain the difference in metastatic behavior in the CNS. We assume that other, as yet unknown factors, must be involved.

Animals↗
PubMed2001

[Development and developmental disorders of the human brain. III. Neuronal migration disorders of the cerebrum].

Neuronal migration disorders of the cerebral cortex form a heterogeneous group of abnormalities, characterised by mental retardation, epilepsy and hypotonia. They are prevalent in 1% of the population and in 20-40% of the untreatable forms of epilepsy. Disorders at the start of the migration result in nodular heterotopias. Bilateral periventricular nodular heterotopias are X-linked disorders, in which cortical neurons are unable to leave their position at the ventricular surface due to the absence of filamin 1. The large group of lissencephalies can be divided into a number of syndromes, each of which is characterised by a gene mutation (LIS1, DCX, RELN). These mutations result in agyria and pachygyria, which are characteristic for this group. A number of these abnormalities, especially the smaller nodular heterotopias and focal cortical dysplasia, may be treated by neurosurgical excision.

Cell Movement↗
PubMed2001

[Development and developmental disorders of the human brain. II. Development of the cerebral cortex and major tract systems].

In the development of the cerebral cortex, two phases can be distinguished: (a) the formation of the preplate, a superficial layer essential for a normal lamination of the cerebral cortex; (b) the formation of the cortical plate. The cortical plate divides the preplate into a superficial marginal zone (the future layer I) and the subplate. The transient subplate is important for the formation of thalamocortical projections. Most cortical neurons arise in the ventricular zone of the pallium and migrate along radial glial cells (radial migration) to the cortical plate. The gamma-aminobutyric acid (GABA)ergic cortical interneurons, however, originate from the ganglionic eminences and reach the cerebral cortex through tangential migration.

Brain↗