Group VIA phospholipase A2 is a target for vasopressin signaling in the thick ascending limb.

Na(+)-K(+)-2Cl(-) cotransporter (NKCC2)-mediated NaCl reabsorption in the thick ascending limb (TAL) is stimulated by AVP via V2 receptor/PKA/cAMP signaling. This process is antagonized by locally produced eicosanoids such as 20-HETE or prostaglandin E(2), which are synthesized in a phospholipase A(2)-dependent reaction cascade. Using microarray-based gene expression analysis, we found evidence for an AVP-dependent downregulation of the calcium-independent isoform of PLA(2), iPLA(2)ß, in the outer medulla of rats. In the present study, we therefore examined the contribution of iPLA(2)ß to NKCC2 regulation. Immunoreactive iPLA(2)ß protein was detected in cultured mTAL cells as well as in the entire TAL of rodents and humans with the exception of the macula densa. Administration of the V2 receptor-selective agonist desmopressin (5 ng/h; 3 days) to AVP-deficient diabetes insipidus rats increased outer medullary phosphorylated NKCC2 (pNKCC2) levels more than twofold in association with a marked reduction in iPLA(2)ß abundance (-65%; P < 0.05), thus confirming microarray results. Inhibition of iPLA(2)ß in Sprague-Dawley rats with FKGK 11 (0.5 µM) or in mTAL cells with FKGK 11 (10 µM) or (S)-bromoenol lactone (5 µM) for 1 h markedly increased pNKCC2 levels without affecting total NKCC2 expression. Collectively, these data indicate that iPLA(2)ß acts as an inhibitory modulator of NKCC2 activity and suggest that downregulation of iPLA(2)ß may be a relevant step in AVP-mediated urine concentration.

Linear and non-linear properties of heart rate in postnatal maturation.

OBJECTIVE: An investigation was made of how postnatal maturation of cardiac control can be described by linear and non-linear methods of time series analysis. METHODS: Sixteen healthy and term newborns were studied during their first 6 months of life. Power spectrum analysis including total power (TP), low frequency power (LF), high frequency power (HF) and LF/HF ratio were performed on the instantaneous heart rate (IHR) time series and mean heart rate (HR) was derived. The largest Lyapunov exponent (LLE) was calculated using a modified Wolf algorithm and checked by means of the surrogate-data test. RESULTS: There is an age dependency for the parameters LLE, HR, TP, HF, LF, LF/HF for active and LLE, HR, TP, HF, LF/HF for quiet sleep. HR is characterised by a steep increase between the 5th and 7th day. HF demonstrates a distinct development with high values around the first week and 90-180th day and low values around the 10-60th day. TP, LF and LF/HF show significantly higher values in active sleep in comparison to quiet sleep. For all ages and sleep stages, positive LLE were found, indicating sensitivity to initial conditions, a hall-mark of chaos. For the period between the 7 and 90th days of life, the LLE for active sleep took on larger values compared with the LLE of quiet sleep. CONCLUSIONS: This study shows that by linear as well as non-linear analysis one can reveal the complexity of the IHR development in humans and may gain insight into the system controlling the heart during the period considered. The positive LLE indicate that there is a non-linear component in the heart rate control. There is no "straight line" development for the parameters analysed within the first 6 months. This may result from manifold influences on the autonomic system, due to structural and functional maturation in this period of life.

Enhanced blood pressure variability in eNOS knockout mice.

It has been shown previously that endogenous nitric oxide can buffer arterial blood pressure variability in dogs and rats. In these former studies, all isoforms of the nitric oxide synthase were blocked pharmacologically and an increased blood pressure variability was observed. Thus the question as to which isoform of the nitric oxide synthase is responsible for the blood pressure buffering effect of endogenous nitric oxide remains unraveled. In the present study, we therefore compared blood pressure variability in knockout mice that lack specifically the gene for endothelial nitric oxide synthase with their respective wild-type controls. One day after carotid artery cannulation, blood pressure was recorded in these conscious mice. During resting conditions, blood pressure variability was markedly enhanced in knockout mice compared with wild-type mice (10.5+/-1.5 mm Hg2 vs 6.0+/-0.8 mm Hg2, P<0.05). Power spectral analysis revealed that this increase in blood pressure variability is manifested at low frequencies that range from 0.05 to 0.40 s-1 (Hz) (5.1+/-1.0 mm Hg2 vs 2.5+/-0.5 mm Hg2, P<0.05). On the basis of these results, we conclude that the blood pressure buffering effect of endogenous nitric oxide is mediated by the endothelial isoform of the nitric oxide synthase. In addition, endothelial nitric oxide is most effective in buffering blood pressure oscillations at frequencies that range from 0.05 to 0.40 s-1 (Hz) in conscious mice.

Dynamics of changes in the acid-base equilibrium of arterial blood and the cerebrospinal fluid in conditions of natural hyperventilation and apnoea.

From investigations on 252 patients the dynamics of changes in the acid-base equilibrium of the cerebrospinal fluid (CSF) and arterial blood were assessed, in conditions of natural changes in breathing rhythm. Gasometric examinations were made several times during natural hyperventilation lasting 4, 5 or 6 min, depending on the examined group, and after apnoea lasting 30 s. The results indicate a specific autonomy of the CSF with respect to the blood, relating to such indices as pH, pCO2 and pO2, in conditions of natural changes in breathing rhythm. This is manifested to varying degrees by differentiation in time of occurrence, depth and direction of changes in the acid-base equilibrium indices in the CSF, relative to the corresponding indices in the blood. On this basis a number of groups were distinguished from among the patients investigated, in whom the clinical state appeared to correlate, to a certain degree, with the degree and direction of changes in the CSF. It is postulated that his specific autonomy of the CSF may be due to the action of regulatory mechanisms at the level of the nerve tissue.

Stabilizing hemostatic clamp for arterial anastomosis in microneurosurgery. Technical note.

The authors describe a "stabilizing hemostatic clamp" of their own design for use in end-to-side anastomosis. Its application facilitates simultaneous stabilization and hemostasis of the cortical artery at the site where anastomosis is to be performed. Using this instrument, the authors have performed anastomosis of the superficial temporal artery with a branch of the middle cerebral artery in 60 patients. On evaluation of the clinical effects of the treatment and results of control angiography, and taking into account the authors' relatively small experience with this type of surgical treatment, they conclude that their new clamp facilitates this form of surgery.

Smear technique in the intra-operative brain tumor diagnosis: its advantages and limitations.

The role of intra-operative pathological diagnosis increases along with a development of minimally invasive neurosurgery, especially stereotactic and endoscopic techniques. The authors present their own experience with the cytological method and evaluate its usefulness in intra-operative diagnosis of brain tumors. Brain tumor biopsy specimens obtained during craniotomy from 217 patients were examined. The cytological preparations (smears) were stained with 1% toluidin blue and/or with May-Grünwald-Giemsa stain. In 199 cases (92%) the cytological diagnosis was consistent with the histopathological one. A 99% sensitivity and 69% specificity were obtained. The histogenesis of gliomas was correctly established in 90% and their grade in 73% of cases. The most frequent diagnostic errors were: undergrading of gliomas (20), incorrect assessment of their histogenesis (10), diagnosis of low grade astrocytoma in a case of gliosis (3) and diagnosis of glioblastoma multiforme instead of metastatic carcinoma (2 cases). The most important advantages of cytological examination are rapidity, simplicity and relatively high diagnostic efficacy. Even very tiny specimens, especially of soft consistency are suitable for this technique, which is extremely important in operations of brain tumors localized in functionally important brain areas. In the authors' opinion this method still merits wider popularization in neurosurgical centers.

Expression of adhesion molecule CD44 in metastatic brain tumors.

Expression of CD44 (m.w. 80-95 kD) in 48 metastatic brain tumors was examined using monoclonal antibody on paraffin sections. The CD44 expression was found in 48% of studied tumors. The most constant expression of CD44 was observed in metastases from thyroid, skin and breast cancer. The brain metastases were characterized by quite heterogenous distribution of CD44 glycoprotein--the most pronounced expression was seen in individual neoplastic cells embedded in abundant stroma and in the vicinity of preserved neural tissue. Such a topographical distribution of CD44 supports its role in interactions of cancer cells with extracellular matrix components of the tumor stroma as well as of neural tissue.

Secretory meningioma of the brain. Report of two cases.

Two cases of cerebral secretory meningioma, occurring in 57 and 33-year-old females are reported. The tumors were located in the tentorial and frontotemporal region, respectively. The general histologic appearance of the tumors was of meningothelial meningioma (case 1) and meningioma with microcystic and angiomatous features (case 2). The most striking histological finding in both tumors were numerous pseudopsammoma bodies, localized chiefly around blood vessels. The inclusions were slightly eosinophilic, stained strongly with PAS method and were differing in size from 3 to 30 microns. Tumor cells containing or surrounding pseudopsammomas were immunopositive for cytokeratin and epithelial membrane antigen. In the first case, individual pseudopsammomas were strongly positive for carcinoembryonic antigen. Some diagnostic aspects of this antigen and problems regarding differential diagnosis in secretory meningioma are briefly discussed.

[Heart rate variability--physiology, methods of registration and application in pediatric sleep laboratory]. / Herzfrequenzvariabilität--Methoden, Physiologie und Applikation im pädiatrischen Schlaflabor.

Heart rate variability (HRV) has become the focus of interest of a multitude of investigations being a parameter that can easily be recorded. Accepted clinical indications in adults include evaluation of diabetic neuropathy and prediction of prognosis after myocardial infarction in adults. In children, HRV is regularly being registered in the pediatric sleep laboratory in sleep related breathing disorders, after apparent life threatening events, or in infants with assumed increased risk for sudden infant death syndrome. However, uniform interpretation criteria have not been established in these situations, at least partially due to insufficient understanding of physiology and pathophysiology of HRV in this age group. In this overview, current knowledge on HRV in infants and children is summarized and its clinical relevance discussed. In addition, technical requirements and methods of analysis which have a major impact on calculated parameters are being presented.

[Evaluation of the activity of various lysosomal enzymes in the cerebrospinal fluid and blood in cases of brain concussion]. / Ocena aktywnosci niektórych enzymów lizosomalnych w plynie mózgowo-rdzeniowym i krwi w przypadkach stluczenia mózgu.

The results of determinations of lysosomal enzymes: mannosidase, b-galactosidase and b-glucosidase, in the cerebrospinal fluid and blood are presented in 72 patients with severe brain trauma. The determinations were carried out at different times after the trauma. The study demonstrated a significantly lower level and in a smaller degree expressed variability of enzymes in the cerebrospinal fluid in relation to blood. It seems that the level of b-glucosidase in the cerebrospinal fluid depends on the level of this enzyme in the blood, while no such evident correlation was found for the remaining enzymes.

[Anastomosis of the extra- and intracranial arteries by a microneurosurgical method in 50 cases of cerebral ischemic syndrome]. / Zespolenie tetnic zewnatrz i wewnatrzczaszkowych metoda mikroneurochirurgiczna w 50 przypadkach zespolu niedokrwiennego mózgu.

The results of treatment of cerebral ischaemic syndromes by a microneurosurgical method in 50 patients are reported. Modifications of the surgical technique in cases of anastomosis of the external temporal artery to the cortical branch of the middle cerebral artery are discussed. The modification includes application of an original stabilizing-haemostatic clip for anastomosing the vessels end-to-side in microneurosurgery, and the use of continuous suture in place of the mostly used single sutures. This makes possible obtaining anastomoses providing optimal conditions for blood flow and being more resistant to the action of factors which could lead to occlusion of vessels.

[Effect of the width of anastomosis between extra- and intracranial arteries on its patency in the light of the flow continuity law and Bernoulli's law]. / Wplyw szerokosci zespolenia tetnic zewnatrz i wewnatrzczaszkowych na jego droznosc w swietle prawa ciaglosci strumienia i prawa Bernoulliego.

On the ground of the results obtained in microneurosurgical treatment of 60 patients with cerebral ischaemia the author analysed the factors affecting the patency of the anastomosis not connected directly with the surgical techniques. The analysis showed the significance of anastomosis width. A relatively wide anastomosis even in cases with correctly performed operation is not contributing to maintenance of patency. This may be explained, in the opinion of the author, by the relationship between the velocity of fluid flow, vessel cross-section area and value of the static pressure calculated from the stream continuity equation and Bernoulli's law.

[A case of aneurysmal bone cyst of orbit roof in a boy aged 14]. / Przypadek torbieli tetniakowatej kosci stropu oczodolu u 14-letniego chlopca.

A case of a very rare localisation of aneurysmal bone cyst within orbital roof is presented. The peculiar site of the pathological process caused two-way expansion, i.e. towards the orbit and the cranial cavity. The patient was operated on using the transcranial approach and total cure was obtained.

[A case of hemorrhagic cerebral abscess with sudden clinical onset]. / Przypadek ukrwotocznionego ropnia mózgu o udarowym przebiegu klinicznym.

A rare case with unfavourable clinical course of haemorrhagic cerebral abscess in the parietal region is presented. Attention is drawn to diagnostic difficulties in cerebral abscesses with non-typical radiological and clinical picture as well as putative mechanisms responsible for haemorrhage within abscess are discussed.

Developmental aspects of the interaction between the controls of heart rate and respiratory rhythm--linear and nonlinear components of diverse activity states in childhood.

Heart beat and respiration are rhythmical phenomena with separate intrinsic frequencies which necessarily have to be effectively tuned by a network of interactive processes. Their linear and nonlinear components may ripen in different ways during childhood thus leading to unstable transitions or risk of dangerous events. This study investigates the development from newborns to children mainly between sleep and wakefulness. 42 healthy untrained children underwent a 24 hours monitoring of ECG, respiration, actogram, and EOG. Linear parameters such as respiratory rate, heart period duration (HPD), total and high frequency spectral power (TP, HFP), low/high frequency power quotient (LF/HF) and coherence were calculated in wake state, REM- and non-REM sleep. The largest Lyapunov exponent (LLE) was evaluated as nonlinear parameter and proved by the surrogate data method. The childrendata were compared to newborndata at days 1 and 180. In wake children, all values except TP differ from that in non-REM and except LLE from that in REM. All linear parameters differ between REM and non-REM. Similar differences exist for quiet to active sleep in newborns at day 1. At day 180 only LF/HF and coherence differ. Development from day 1 to 180 exists in quiet sleep for LF/HF and coherence, in active sleep additionally for LLE and from day 180 to children except for LF/HF and coherence. The results show clear differences in the linear parameters of the activity states. Wakefulness, REM- and non-REM sleep, therefore, follow varied rhythmical controls. The behaviour of LF/HF points to changes in the intensity of vagal participation and that of the coherence accentuates the differing tightness of the coupling. The clearly existing nonlinear components have a separate value only in wakefulness hinting at larger complexity at that state. The development within the first 180 days indicates an increase of vagal participation and tightness of coupling in quiet sleep, in active sleep also an increase in complexity. From that day no further development in vagal and coupling effects has been detected among children. The complexity remains unchanged, only the power parameters expressing heart rate variability increase. (Fig. 3, Tab. 3, Ref. 13.)

[Newly formed intracranial saccular aneurysms revealed within several years after surgery for the aneurysm with different localization: report of 2 cases]. / Nowopowstale wewnatrzczaszkowe tetniaki workowate ujawnione w okresie kilku lat od operacji tetniaka o innej lokalizacji--opis 2 przypadków.

The authors present two patients treated surgically for intracranial aneurysms. Within 2.5 and 4.6 years after surgery the repeated angiography performed after the second SAH revealed newly formed aneurysms in another localisation. These facts became a contribution to the etiopathogenetic considerations.

[Neuropsychological changes in cerebral ischemia after treatment by the microneurosurgical method. Preliminary report]. / Dynamika zmian neuropsychologicznych w zespolach niedokrwiennych mózgu w nastepstwie leczenia metoda mikroneurochirurgiczna.

The results of neuropsychological examinations are reported in 35 patients with ischaemic cerebral syndromes subjected to microneurosurgical treatment with creation of anastomoses between extracranial and intracranial arteries. A great number of psychic function disturbances were found in them occurring characteristically in lesions of the frontal and temporal lobes. In the groups of patients with transient ischaemic attacks and prolonged reversible ischaemic attacks these disturbances regressed mostly after the operation, parallelly with sings of focal lesion. In the group of patients with completed stroke in most cases an improvement was observed in the psychic functions despite lack of neurological improvement. The results of neuropsychological examination in cases of ischaemic cerebral syndromes indicate thus the necessity of extending indications to microneurosurgical treatment in patients with evidence of completed stroke.

[Cerebral ischemia in young patients]. / Zespól niedokrwienny mózgu u ludzi mlodych.

The clinical, angiographic and computed tomography (CT) examinations of 19 patients aged from 12 to 30 years with signs of ischaemic brain syndrome are presented. On the basis of these examinations and data obtained from literature it is supposed that in a majority of patients the disease is caused by basal arteriopathies + i.e. pathological changes in the wall of cerebral arteries, mainly of the circulus Willis. The features distinguishing this syndrome from ischaemic disease in adults are presented and discussed. These are first of all: sudden onset connected with physical effort, deep neurological deficit, narrowing or occlusion of basal cerebral arteries seen in angiography and signs of ischaemia within deep cerebral structures visible in CT. The methods of treatment are discussed, mainly STA-MCA anastomosis used in most cases. The results of treatment are discussed. Finally the problem of the cerebral ischaemic syndrome in young people is presented from the point of view of haemodynamics, principally in the aspect of haemodynamic reserve of cerebral blood flow.

[Multiple spinal meningeal cysts in the thoracic region associated with lymphedema of the legs (Milroy's disease)]. / Mnogie torbiele nadoponowe w odcinku piersiowym kregoslupa wspólistniejace z zespolem obrzeku limfatycznego konczyn dolnych (choroba Milroya).

Intraspinal extradural meningeal cysts are uncommon cause of spinal compression. Either the classification or the etiopathology of these changes are indistinct in the literature. A rare case of multiple extradural meningeal cysts associated with lymphedema of the legs is presented. The total surgical removal was followed by the quick neurological improvement. Some etiological, diagnostic and therapeutic aspects of these pathologies have been discussed.

[A case of Morgagni-Morel-Stewart syndrome with violent headaches predominant in the clinical course treated surgically]. / Przypadek zespolu Morgagniego-Morela-Stewarta z bólami glowy dominujacymi w obrazie chorobowym leczony operacyjnie.

The authors present a case of Morgagni-Morel-Stewart syndrome with violent headaches predominant in the clinical course. Surgical removal of hypertrophic frontal bone followed by dura and bone reconstruction was performed. The pains ceased immediately after the operation. The authors discuss surgical treatment especially in cases with high intensity headaches.