Changes in gonadotropin-releasing hormone and gonadotropin-releasing hormone receptor gene expression after an increase in carbon monoxide concentration in the cavernous sinus of male wild boar and pig crossbread.

Previous studies indicate that there are at least a few regulatory systems involved in photoperiodic synchronisation of reproductive activity, which starts with the retina and ends at the gonadotropin-releasing hormone (GnRH) pulse generator. Recently we have shown indicated that the amount of carbon monoxide (CO) released from the eye into the ophthalmic venous blood depends on the intensity of sunlight. The aim of this study was to test whether changes in the concentration of carbon monoxide in the ophthalmic venous blood may modulate reproductive activity, as measured by changes in GnRH and GnRH receptor gene expression. The animal model used was mature male swine crossbred from wild boars and domestic sows (n = 48). We conducted in vivo experiments to determine the effect of increased CO concentrations in the cavernous sinus of the mammalian perihypophyseal vascular complex on gene expression of GnRH and GnRH receptors as well as serum luteinizing hormone (LH) levels. The experiments were performed during long photoperiod days near the summer solstice (second half of June) and short photoperiod days near the winter solstice (second half of December). These crossbred swine demonstrated a seasonally-dependent marked variation in GnRH and GnRH receptor gene expression and systemic LH levels in response to changes in CO concentration in ophthalmic venous blood. These results seem to confirm the hypothesis of humoral phototransduction as a mechanism for some of bright light's effects in animal chronobiology and the effect of CO on GnRH and GnRH receptor gene expression.

Aneurysm of the meningeal branch of the occipital artery connecting with the distal portion of the posteroinferior cerebellar artery by the dural fistula.

We describe a case involving a ruptured intradural aneurysm of the meningeal branch of the occipital artery arising from the external carotid artery and connecting with the caudal loop of the posteroinferior cerebellar artery (PICA) by the dural fistula. Angiography of the left external carotid artery showed a saccular aneurysm of the occipital artery, but the picture of the left vertebral artery was normal and no vascular pathology such as an aneurysm or a dural fistula was noticeable between the meningeal branch of the occipital artery and the PICA. The diagnosis was confirmed by three-dimensional reconstruction computed tomography (CT) angiography, magnetic resonance imaging and magnetic resonance angiography (MRA). In the knowledge, based on the radiological examinations, that the aneurysm was located intracranially below the tonsil, compressing the lateral surface of the medulla oblongata at the level of the foramen magnum, we decided to operate from the far-lateral suboccipital approach, without removing the arc of the C1. An aneurysm was visualised at the site of the connection of the caudal loop of the PICA and an anastomosis of the meningeal branch of the occipital artery. The aneurysm was successfully clipped and the vascular fistula was coagulated and dissected in the extradural section. To our knowledge, the case presented here is the first report of this kind of vascular pathology. Careful analysis of a cross-sectional CT angiogram, MRA and arteriography is necessary for the proper diagnosis of such atypical vascular pathology. In the study presented we focus our attention on the diversity of the PICA anatomy.

BCR expression is decreased in meningiomas showing loss of heterozygosity of 22q within a new minimal deletion region.

Neurofibromin 2 (NF2), located on chromosome arm 22q, has been established as a tumor suppressor gene involved in meningioma pathogenesis. In our study, we investigated 149 meningiomas to determine whether there are additional tumor suppressor genes localized on chromosome 22q, apart from NF2, that might be involved in meningioma pathogenesis. The LOH analysis on chromosome 22q identified two regions of deletion: the first one, which is limited to the NF2 gene locus, and the second one, which is outside this location. The new minimal deletion region (MDR) included the following genes: BCR (breakpoint cluster region), RAB36 (a member of RAS oncogene family), GNAZ [guanine nucleotide binding protein (G protein), alpha-z polypeptide], and RTDR1 (rhabdoid tumor deletion region gene 1). The expression levels of all these genes, including NF2, were subsequently analyzed by quantitative real-time polymerase chain reaction. We observed a significantly lowered expression level of NF2 in meningiomas with 22q loss of heterozygosity (LOH) within NF2 region compared to the one in meningiomas with 22q retention of heterozygosity (ROH, P<0.05). Similarly, BCR showed a significantly lowered expression in meningiomas with 22q LOH within the new MDR compared to cases with 22q ROH (P<0.05). Our data, together with the already published information considering BCR function suggest that BCR can be considered as a candidate tumor suppressor gene localized on chromosome 22q which may be involved in meningioma pathogenesis.

[Correlation of expression of progesterone receptors with histopathological type and grade of malignancy of cerebral neoplasms]. / Powiazanie ekspresji receptorów progesteronu z budowa histopatologiczna i stopniem zlosliwosci nowotworów wewnatrzczaszkowych.

Steroid receptors play an important role in homeostasis and in proliferation of neoplastic cells as well. Biological effect of steroid hormone on tissues depends on intracellular concentration of its receptor. The binding hormone with its receptor activates adequate genes in cellular nuclei and cell proliferation. The mutation of genes codifying of receptor protein may cause its structural modification or changes in its activity and lead to neoplastic transformation. The aim of our work was the estimation of progesterone receptors (PR) concentration in cerebral neoplasma and correlation with histopathological type and grade of malignancy of cerebral tumours. We examined 89 patients, among them 28 with meningioma, 43 with glioma and 18 with metastatic tumour. The concentration of PR was evaluated using radioreceptor assay. Our results show statistically significant correlation between expression of PR and type and malignancy of neoplastic tumours. It was especially seen in meningioma and the highest concentration of PR were in I grade tumours.

[Syringohydromyelia--coexistence or complication following removal of meningioma of forth ventricle]. / Jamistosc rdzenia--wspólistnienie czy powiklanie po operacji oponiaka IV komory mózgu.

Numerous theories have been presented to explain the pathogenesis of syringohydromyelia. Among these is Gardner's hydrodynamic theory with later modifications. Syrinx is usually located in cervical cord and is often associated with Arnold-Chiari, Dandy-Walker malformation or other anomalies of cranio-cervical region. Other theories suggest that syringohydromyelia may be secondary to arachnoiditis, neoplasms or spinal cord trauma. The distal location of the syrinx is very often associated with occult spinal dysraphic lesion. The authors present the case of 28 years old woman operated on meningioma of fourth ventricle. One and a half year later syrinx on Th11-Th12 and coexistent arachnoiditis were recognized. They stress diagnostic and therapeutic difficulties in this case and try to explain of etiology of syringohydromyelia.

[Vascular endothelial growth factor expression in cerebral neoplasms]. / Ekspresja czynnika wzrostowego sródblonka naczyn w nowotworach mózgu.

Angiogenesis plays an important role in growth of neoplasm. Among a variety of proangiogenic agents, vascular endothelial growth factor (VEGF) is regarded as a crucial mediator of tumour angiogenesis. It acts in a paracrine way through the receptors localised in endothelial cells. Many authors maintain that rich vasculature of the neoplasm is associated with its malignant nature. The aim of this study was to examine the relations between expression of VEGF and features of malignancy of brain tumours. Sixty-seven samples of brain tumours were examined: 17 meningiomas, 34 gliomas and 16 metastases to the central nervous system. Expression of VEGF was estimated by radioimmune assay. The authors confirmed the presence of this factor in all types of tumours but the highest concentration of VEGF was found in high-grade gliomas.

[Correlation of steroid receptors and growth factors expression with peritumoral edema accompanying cerebral neoplasms]. / Ekspresja receptorów steroidowych i czynników wzrostowych a obrzek towarzyszacy nowotworom mózgu.

The aetiology of peritumoral brain oedema still remains unclear, despite investigations, attempted to study the role of various clinical factors and histological features of the tumour. The aim of this investigation was to the evaluate correlation of peritumoral brain oedema with expression of progesterone (PR) and oestrogen (ER) receptors and vascular--endothelial growth factor (VEGF). Eighty nine samples of brain tumours were examined, among them 28 meningiomas, 43 gliomas and 18 metastatic tumours. Expression of steroid receptors was examined with the radioreceptor assay method and expression of VEGF by radioimmune assay. A statistically highly significant correlation was found of VEGF expression with the incidence of diffuse pattern of brain oedema around gliomas and metastatic tumours (p < 0.01). PR expression was associated significantly with the occurrence of localized type of oedema around meningiomas, but in gliomas the expression of this receptor correlated with a diffuse pattern of oedema. No correlation was found between ER expression and peritumoral brain oedema.

[Epidermal growth factor expression in brain neoplasms]. / Ekspresja czynnika wzrostowego naskórka w nowotworach mózgu.

Epidermal growth factor (EGF) influences the cell by activation of its specific cell receptor (EGFR). It is regarded as one of the most effective mitogenic factors and plays a role in carcinogenesis. The aim of this study was the assessment of EGF expression in different types of cerebral neoplasms and searching for its correlation with histopathologic features of malignancy and presence of peritumoral oedema. Sixty seven samples of brain tumours were examined. Among them were 17 meningiomas, 34 gliomas and 16 metastases. Expression of EGF was estimated by a radioimmune assay. The authors found the presence of EGF in all types of tumours. No correlation was found between expression of EGF and histopathological signs of tumour malignancy, although a tendency appeared towards a higher level of that factor in anaplastic tumours. Also, no correlation was found between EGF and peritumoral oedema.