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Zbigniew Czernicki

Publications and source records attributed to Zbigniew Czernicki.

14 recordsLinked to original sources
PubMed2006

Involvement of immature endothelial cells in vascular alterations in Alzheimer's disease.

The aim of the present study was to investigate ultrastructural features of cerebral capillaries and the pattern of new vessel formation in a patient with Alzheimer's disease (AD). Recent neuropathological studies have demonstrated that patients with AD have cerebrovascular pathology. Using electron microscopy, we showed that alterations of the capillaries are a common finding both in vascular disease and in AD, suggesting that vascular factors may also play a role in the pathogenesis of AD. We also found regionally increased capillary density, and in many sections immature endothelial cells lying on the preexisting endothelium were present in the lumen of capillaries. These cells might thus contribute to the pathological pattern of capillaries. The cytoplasm of immature endothelial cells in the patient with AD was characterized by accumulation of amyloid fibrils. We suggest that immature endothelial cells may be an important source of circulation-derived amyloid in the brain.

Aged↗
PubMed2005

Hemosiderin pigmentation of tumour cells in cerebellar pilocytic astrocytoma associated with post-traumatic hemorrhage in adults.

The pilocytic astrocytoma is only rarely associated with gross intratumoral hemorrhage despite rich vasculature and blood vessel changes, accompanied often by perivascular depots of hemosiderin. We report an unusual case of pigmented cerebellar pilocytic astrocytoma presenting with posttraumatic hemorrhage in a 38-year-old man with no history related to the tumor. CT and MRI examination after head injury demonstrated unexpectedly the cystic lesion of 2 cm in diameter in the region of the right cerebellar hemisphere and vermis. The lesion was associated with hematoma and it was surgically removed 3 weeks after trauma. Histopathological examination revealed pilocytic astrocytoma tissue with broad hemorrhagic changes and with an unusual pattern of massive pigmentation of the cytoplasm of pilocytic astrocytes, consistent with hemosiderosis. Positive stains for iron and ferritin and ultrastructural study confirmed deposition of hemosiderin granules in the tumour cells. There was no evidence of melanin or melanosomes. This finding of hemosiderin accumulation in the cytoplasm of neoplastic astroglia seems to be analogous to post-hemorrhagic pigmentation of the normal Bergmann glia and subpial astrocytes. In the literature, the examples of neuroepithelial tumors with hemosiderin pigmentation of tumor cells have been rarely documented. To our knowledge, this is the first reported case of pigmented pilocytic astrocytoma exhibiting extensive intracellular hemosiderin deposition.

Adult↗
PubMed2004

The concentration of thyroid hormones and activities of iodothyronine deiodinases are altered in human brain gliomas.

We have determined the cellular concentration of thyroxine (T4) and triiodothyronine (T3) and the activities of two brain iodothyronine deiodinases, type II (5'-D2) and type III (5-D3), in two types of tissues --tumour (26) and non-tumour (5), derived either from human gliomas with various histological malignancies or from non-tumoural surrounding brain tissue. As it has been established, all patients before the surgery had the Non-Thyroidal Illness Syndrome (NTIS). The concentration of serum T3 was therefore significantly decreased in all the examined patients. It was over 2.5 times lower than that before surgery and 4.0 times lower at surgery than that seen in healthy controls. The serum concentration of T4 was found to be below normal range in 4/26 cases and in low levels of normal range in 6/26 cases, whereas TSH serum concentration in all patients was within normal range. The concentrations of T3 and T4 (expressed as pg of hormone/mg tissues protein) in 22/26 brain tissue samples were significantly lower in gliomas than in 5 non-tumoural brain tissue samples. As expected, the alternation in brain 5'D II activity in gliomas was seen in most cases with astrocytomas (5/8 cases), gliosarcomas (8/8 cases) and glioblastoma multiforme (10/10 cases). In general, the mean enzyme activity in tumour tissue was significantly higher than that found in non-tumoural tissue of human brain (21.79 fmol of newly generated T3/h/mg of protein vs. 4.88 fmol of T3/h/mg protein, respectively). The highest 5'D2 activity with a range from 10.82 to 45.96 (mean 23.61 fmol T3/h/mg protein) was found in gliosarcomas. The activity of 5-D3 was increased (in 8/8 cases of gliosarcoma and in 9/10 cases of glioblastoma multiforme) or decreased (in 3/3 cases of astrocytoma II, 5/5 cases of astrocytoma III) when compared to mean activity of this enzyme found in non-tumoural brain tissue. In summary, our results suggest that the concentration of brain iodothyronines and metabolism of thyroid hormones in the examined human brain tumours are altered. These changes may be related to malignant progression.

Adult↗
PubMed2004

Cerebrospinal fluid free-radical peroxidation products and cognitive functioning patterns differentiate varieties of normal pressure hydrocephalus.

The aims of the study were as follows: first, to verify the hypothesis that free radical peroxidation may be one of the factors implicated in pathophysiology of normal pressure hydrocephalus (NPH) and, second, to find out whether these biochemical characteristics together with neuropsychological cognitive deficits can differentiate between various types of NPH. This provides prognostic criteria for selection of patients for shunt surgery. Lipid peroxidation was measured in terms of thiobarbituric acid-reactive material (TBAR) and protein sulphydryl (SH) groups were measured as CSF content. Cognitive deficits were assessed using a number of neuropsychological tests. In the sample of NPH patients (n = 24), three categories were distinguished using these criteria: idiopathic active hydrocephalus (A), arrested hydrocephalus (AH), and post-traumatic hydrocephalus (PT). TBAR levels for NPH patients were higher than that of controls without CNS pathology (n = 2). Moreover, NPH patients had increased levels of total and soluble protein groups, and decreased levels of protein SH groups, which suggests the occurrence of processes that activate peroxidation of free radicals in normal pressure hydrocephalus. Levels of these indicators varied across NPH types. Two categories of NPH patients, with active (A) or posttraumatic (PT) hydrocephalus differed significantly from the controls (C)--their TBAR levels were 0.58, 0.56 and 0.28 nmol/mg protein, respectively; soluble SH levels: 41.5; 58.15 and 11.3 nmol/mg protein, and protein SH levels: 34.3, 21.8 and 57.5 nmol/mg protein. In PT group, many individual differences were noticed. These findings seem promising because the studied biochemical indicators may serve as additional diagnostic criteria for selection of NPH patients for shunting.

Biomarkers↗
PubMed2003

Clinicopathological and ultrastructural study in two cases of chordoid glioma.

Chordoid glioma is a rare benign neoplasm of uncertain histogenesis occurring in the third ventricle/ /suprasellar region. Recently, data have emerged suggesting that chordoid glioma is a variant of ependymoma related to a specialised ependyma of the subcommisural organ or the lamina terminalis area. In this study, we report clinicopathological and ultrastructural findings in two chordoid glioma cases. In case 1, a tumour (1.5 cm in diameter) in a 62-year-old man invaded the anterior-basal part of the third ventricle in the lamina terminalis region. In case 2, a large tumour in a 51-year-old woman occupied the whole third ventricle. The tumour attached to the medio-basal hypothalamic region. Histologically, both cases revealed a distinct chordoma-like pattern and glial immunophenotype of tumour cells. Under the electron microscope the tumour cells exhibited microvilli, intercellular lumina, intermediate type junctions and focal basal lamina formations. These findings were similar to those previously reported in the chordoid glioma cases. Moreover, the intracytoplasmic cilia and subplasmalemmal pinocytic vesicles or caveoles were observed. The study supports the view of ependymal derivation of chordoid glioma. Its relation to lamina terminalis or infundibular/median eminence area presumably reflecting tumour origin from the modified ependyma of circumventricular organs of the third ventricle is discussed.

Cerebral Ventricle Neoplasms↗
PubMed2003

Surgical treatment of brainstem tumours with special emphasis on the operative approach through the fourth ventricle floor.

Over the last 25 years there have been reports from the widely recognised neurosurgical centres on the positive clinical results of partial and even complete removal of brainstem tumours. They confirmed relatively high incidence of benign tumours like low-grade gliomas and haemangioblastomas in this region. Based on imaging studies (MRI) and surgical experiences, brainstem tumours can be divided into focal and diffuse. Focal lesions are amenable to surgery; particularly, those with a prominent exophytic portion. Open surgery remains controversial in pure intrinsic brainstem tumours as the surgical approach itself may lead to serious postoperative complications. Different approaches (including the most frequent one--through the fourth ventricle floor) are used depending on the tumour location. As minimal invasiveness is mandatory during transtegmental route safe approach zones within the rhomboid fossa were defined morphologically and morphometrically--suprafacial and infrafacial (i.e., situated above and below facial colliculus, respectively). Application of the proposed minimal invasive surgical approach through the fourth ventricle floor should reduce postoperative morbidity and mortality in patients with tumours in pons and upper medulla oblongata treated surgically.

Brain Stem Neoplasms↗
PubMed2002

Familial incidence of obstructive hydrocephalus due to posterior fossa tumours leading to the diagnosis of von Hippel-Lindau disease--a case report.

Von Hippel-Lindau disease (VHLD) is an autosomal dominant disorder predisposing to the development of different histological types of tumours with predominance of CNS haemangioblastomas in the majority of cases. We present a case of a 35-year-old man with obstructive hydrocephalus due to multiple posterior fossa tumours. Familial history revealed two relatives operated on previously because of a posterior fossa tumour (in one case haemangioblastoma was diagnosed). During surgery two cerebellar tumours were removed radically via the suboccipital approach. On a histopathological examination the typical features of haemangioblastoma were found in both tumours composed of stromal cells and a dense network of vessels, mostly capillaries. The presence of neoplastic infiltration with angiogenesis in the surrounding cerebellar tissue was evidenced in the presented case. Based on the clinical and histopathological data VHLD was diagnosed. Genetic analysis confirmed the presence of the von Hippel-Lindau gene mutation. The case presented suggests that genetic disregulation in VHLD may be responsible for a more aggressive behaviour of VHLD-related haemangioblastomas in comparison with sporadic disease.

Adult↗
PubMedDate not supplied

[The first system of image transmission and neurosurgical telecommunication in Poland].

OBJECTIVE: The goal was to develop a fast and efficient neurosurgical teleconsulting network to improve acute neurosurgical patient care, to reduce transport costs and unnecessary occupation of neurosurgical beds. METHODS: Modems with 56 kilobits/s data transmission speed are used. CT images are transmitted straight from CT scanner via modem/telephone lines to receiving personal computer in Department of Neurosurgery. Receiving PC runs with Microsoft Windows operating system and the network software MultiView (EMED, Inc.). Network connects Department of Neurosurgery Polish Academy of Sciences in Warsaw with transmitting hospitals in Ciechanów and Ostrołeka. RESULTS: The system is fast, one study consisting 18 images is transmitted in about 5 minutes and it is simple to use, to date more than 1000 CT images have been transmitted. Operator acceptance has been very high. The system has improved acute neurosurgical patient care. Transfer of appropriate patients has been accelerated and unnecessary transfer is almost eliminated. CONCLUSION: Applied Neurosurgical Teleconsulting System has significantly improved acute neurosurgical patient care and has reduced transport expenses. Better availability of neurosurgical consultation has been achieved. The network is simple to use and has gained physician acceptance. It has to be emphasized that the creation and using of the system is relatively not expensive.

Computer Communication Networks↗
PubMedDate not supplied

[The molecular basis of glia-derived tumours of the brain. Part I].

The development and progression of astrocytic tumours is associated with acquisition and accumulation of genetic alternations. Loss of heterozygosity (LOH) on chromosome 17p., p53 mutations and overexpression of the platelet-derived growth factor (PDGF) receptor (chromosome 22q), are the most common detectable changes in astrocytomas (WHO grade II). Anaplastic astrocytomas (WHO grade III) involve LOH on chromosome 19q, deletion of p16 tumor suppressor gene on chromosome 9p and disturbed expression of gene RB on chromosome 13q. LOH on chromosome 10 is restricted largely to glioblastomas (WHO grade IV). This tumour also is characterized by amplification and/or overexpression of gene coding Epidermal Growth Factor Receptor (EGFR) on chromosome 7p. There is growing evidence that two genes encoding triiodothyronine receptors TR alpha [17q21] and TR beta [3p21-p25]) belong also to the group of genes involved in tumorigenesis. Mutations of these genes as well as markedly disturbed expression and function of the encoded proteins were found in tumour tissue. This is supported by facts. that T3 via TRs regulate proliferation, growth, differentiation and apoptosis, the processes that are deeply disturbed in tumour tissue. TRs affects also the action of certain protooncogenes (Mdm2) and tumor suppressors (p53, Rb).

Astrocytoma↗
PubMedDate not supplied

[The effectiveness of microvascular decompression in various types of vascular compression in patients with trigeminal neuralgia].

The aim of the work was to evaluate the efficacy of microvascular decompression (MVD) in different types of vascular compression (VC) in 20 patients with the idiopathic form of trigeminal neuralgia (TN). The typical VC was found in 17 cases. An arterial vessel was the cause of VC in 6 cases, a venous vessel in 5. The mixed type of VC was present in 6 cases. In every case of the mixed VC one of the vessels compressing the 5th nerve predominated: arterial in 5 and venous in 1. In 3 cases of TN no VC was found. Observation time after MVD was from 6 to 61 months (median 26.7 months). In the TN patients with the arterial VC (including the mixed VC with the arterial predominance) pain relief was complete in 7 cases, satisfactory in 2 and none in 1 case. In patients with venous VC (including mixed VC with venous predominance) pain relief was complete in 4 cases and satisfactory in 2. In the TN patients without VC pain relief was satisfactory in 1, unsatisfactory in 1 and none in 1 case. Long term results of MVD in the analyzed series of the TN patients confirm the efficacy of MVD when vascular compression of the 5th nerve--either arterial or venous--is found intraoperatively.

Adult↗
PubMedDate not supplied

[Glia-like brain tumors. Potential role of thyroid hormone and its nuclear receptors (TR)].

Over-proliferation of certain cells lead to tumor formation and therefore impairments of regulation of the cell cycle are inalienable and basic signs of neoplasms. The majority of known oncogenes and tumor suppressors are components of a few common signaling pathways that control the cell cycle, genome integrity, cell differentiation and apoptosis. Changes in these signaling pathways cause the development of tumor genesis. The thyroid hormones (3, 5, 3'-L-triiodothyronine, T3; 3, 5, 3', 5'-L tetraiodothyronine, T4; TH) play crucial roles in the growth and differentiation of many organs, including the central nervous system. TH exerts its major effect by binding to the nuclear TH receptor (TR). TR is bound to specific DNA sequences known as TH-response elements (TREs), composed of two half-site core motifs (AGGTCA), with specific nucleotide spacing and orientation. TR also bind to several coregulators such as corepressors and coactivators. The liganded complexes ultimately determines nuclear TH action. .

Apoptosis↗
PubMedDate not supplied

[Does left-handedness affect the pattern of cerebral blood flow during cognitive activity?].

In most people the left hemisphere of the brain is dominant for language functions. Because of an increased incidence of atypical language lateralisation in the right hemisphere of left-handed neurological patients, more systematic studies on handedness and cerebral asymmetry of language have been undertaken. The present study is aimed at clarification of the relationship between handedness and language dominance in healthy subjects. Lateralisation was measured directly using functional transcranial Doppler sonography in left-handed subjects. Twenty-six individuals participated in the study. Three kinds of tasks were used, differing in the material involved and in appropriate strategies to be employed by the subjects. Two important parameters of the MCA blood flow were analysed: mean relative increase in the blood flow velocity (MDV) and specific patterns of cognitive task performance (i.e. performance profiles). Our results indicate that the incidence of the right hemisphere dominance for language depends on the degree of handedness, since only in the group of consistent left-handers language was right lateralised. In other left-handers both cerebral hemispheres were functionally equivalent. The measurement of MCA blood flow velocity changes using transcranial Doppler ultrasonography seems to be a simple and non-invasive method of assessing the functioning of the two hemispheres of human brain.

Adult↗
PubMedDate not supplied

[Difficulties in microsurgical treatment of aneurysms after coiling].

BACKGROUND AND PURPOSE: The paper presents our own experience with microsurgical clipping of the cerebral aneurysms previously treated using endovascular techniques. MATERIAL AND METHODS: The presented clinical material consists of 3 patients treated in such a way. A group of 60 patients was embolized. An initial satisfactory effect of endovascular treatment was verified within 12 months of observation. Control radiological examinations--plane skull x-ray and cerebral angiography (DSA)--revealed coil displacement and recanalization of the aneurysm. In each case a surgical clipping of the aneurysms was performed. RESULTS: Proper clipping of previously coiled aneurysms sometimes presents a serious problem. Certain difficulties included rebuilding of the aneurysmal wall with a change of anatomical configuration in vessel ramifications. CONCLUSIONS: Qualification for endovascular treatment and the existing risk of introduction of additional coils into the aneurysm sac was discussed in connection with our observations. Problems concerning surgical treatment of initially embolized cerebral aneurysms were discussed and illustrated. Radiological monitoring of patients after endovascular treatment was proposed.

Adult↗