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Parkinson’s disease (PD) is a neurodegenerative disorder mainly diagnosed in elderly patients, which is now considered incurable. To date, there are no effective neuroprotectors suitable to treat PD patients. We have previously demonstrated that U133 therapy, which induces the synthesis of Hsp70 and Hsp40 heat shock proteins in the brain, prevents the development of neurodegeneration in the nigrostriatal system and eliminates sleep disorders in an animal model of PD. In the present study, we assessed the antidepressant properties of preventive U133 therapy, as well as its neuroprotective effect on monoaminergic emotiogenic brain structures in a preclinical model of PD in aged (20-month-old) Wistar rats, created by intranasal administration of the proteasome inhibitor lactacystin. It was found that intraperitoneal U133 administration in aged animals led to a delayed (after 3–7 days) elevation of the Hsp70 (HSPA1) level in the midbrain ventral tegmental area and locus coeruleus. Preventive U133 therapy eliminated the manifestations of depression-like behavior in the form of anhedonia, which develops during the preclinical stage of PD in aged rats. It was established that the antidepressant-like effect of the chaperone inducer U133 is due to the ability of the Hsp70 chaperone to attenuate neurodegeneration and neuroinflammation in the dopaminergic mesolimbic reward system and locus coeruleus noradrenergic system. The data obtained may serve as a fundamental basis for the development of a novel chaperone inducer-based molecular technology for preventive therapy of polyetiological PD and concomitant anhedonia.

Parkinson’s disease (PD) is a chronic relentlessly progressive neurodegenerative disease mainly affecting dopamine (DA)-ergic neurons in the nigrostriatal system of the brain. PD mostly affects elderly people and is incurable. Impairments to the conformation of α-synuclein protein and its hyperphosphorylation, along with the development of chronic neuroinflammation, are the main components in the pathogenesis of neurodegeneration in PD. Pharmacotherapy directed to mobilizing the stress-induced chaperone Hsp70, which plays a key role in controlling the quality of protein molecules and has immunomodulatory activity, has potential in developing preventive treatment for PD. This study used a model of the preclinical stage of PD in elderly rats created by intranasal administration of proteasome inhibitor lactacystin. Rats were treated with a scheme based on systemic administration of an Hsp70 chaperone inducer – the low molecular weight quinoid compound U133 (acetylated echinochrome 2,3,7-tris-O-glucoside). Compound U133 was found to induce a time-delayed increase in Hsp70 content in the pars compacta of the substantia nigra (SNpc) in elderly animals. Preventive Hsp70-induced therapy with U133 in the model of the preclinical stage of PD in elderly rats weakened the process of neurodegeneration in the SNpc and countered the development of neuroinflammation. There were reductions in the quantity of aggregated α-synuclein and regression of α-synuclein posttranslationally modified by phosphorylation at Ser129. These data provide evidence that the prodrug, low molecular weight substance U133, has significant therapeutic potential in the development of Parkinson’s-like pathology at elderly age. The study results have scientific and applied importance in terms of the development of innovatory technologies for the preventive pharmacotherapy of PD based on the Russian substance U133.

Evaluation of the impact of surgical treatment on malignant transformation (MT) of adult supratentorial infiltrative grade II gliomas (G2G) in a series of chemotherapy and radiotherapy-naïve patients.Despite G2G are slow-growing tumours, they typically undergo MT with a subsequent fatal disease course. An extensive resection alone likely changes their biological behaviour and defers MT; however, this impact is not unequivocally confirmed.Thirty-eight chemotherapy and radiotherapy-naïve adult patients operated from 2005 till 2014 for a G2G were investigated. Based on postoperative magnetic resonance imaging (MRI) and/or positron emission tomography follow-up (FU) scans, the patients were classified as "transformers" (15 patients in whom MT occurred during the FU-period) and "non-transformers" (23 patients).The follow-up period of "non-transformers" was longer (p0.0001). After adjustment for known risk factors - age, male sex, astrocytoma histology, preoperative tumour volume, preoperative contrast enhancement and positive isocitrate dehydrogenase 1 gene mutation status - a larger log postoperative tumour volume (p=0.031) and a smaller extent of resection (p=0.0086) were associated with a shorter MT-free survival.In our series, less extensive resections were associated with a shorter time to MT. Our data support an adoption of techniques enabling extensive G2G resections, such as intraoperative imaging and awake resections, into everyday routine (Tab. 1, Fig. 2, Ref. 40).

Previously, we have characterized the capsaicin-insensitive low pH-sensitive (caps−lpH+) subtype of small-sized nociceptive dorsal root ganglion (DRG) neurons that express acid-sensing ion channels, T-type Ca2+ channels, and have isolectin B4-negative phenotype. These neurons demonstrated increased excitability in a model of long-term diabetes, contributing to chronic pain sensation. Here we studied changes in the excitability of the caps−lpH+ neurons and underlying changes in the functional expression and gating properties of ion channels under complete Freund's adjuvant (CFA)-induced peripheral inflammation. We have found that, under these pathological conditions, the functional expression of the acid-sensing ion channels (ASICs) and voltage-gated Na+ channels, was increased. In addition, T-type Ca2+ current was significantly increased in the neurons at the membrane potentials close to its resting value. Altogether, the observed changes in the channel functioning shifted a pH level evoking an action potential (AP) toward its physiological value and led to an increase of evoked and spontaneous excitability of the caps−lpH+ neurons that may contribute to hyperalgesia and chronic inflammatory pain.

Numerous investigations implicate pronounced changes in the functioning of T-type Ca2+ channels localized on the somata of primary nociceptor units in the development and maintenance of painful diabetic neuropathy. This review highlights the role of T-type Ca2+ channels of nociceptive afferents in the processing of pain signals under diabetic conditions, as well as suggests a promising therapeutic strategy to treat painful diabetic neuropathy.

The spinal gray matter region around the central canal, lamina X, is critically involved in somatosensory processing and visceral nociception. Although several classes of primary afferent fibers terminate or decussate in this area, little is known about organization and functional significance of the afferent supply of lamina X neurons. Using the hemisected ex vivo spinal cord preparation, we show that virtually all lamina X neurons receive primary afferent inputs, which are predominantly mediated by the high-threshold Aδ- fibers and C-fibers. In two-thirds of the neurons tested, the inputs were monosynaptic, implying a direct targeting of the population of lamina X neurons by the primary nociceptors. Beside the excitatory inputs, 48% of the neurons also received polysynaptic inhibitory inputs. A complex pattern of interactions between the excitatory and inhibitory components determined the output properties of the neurons, one-third of which fired spikes in response to the nociceptive dorsal root stimulation. In this respect, the spinal gray matter region around the central canal is similar to the superficial dorsal horn, the major spinal nociceptive processing area. We conclude that lamina X neurons integrate direct and indirect inputs from several types of thin primary afferent fibers and play an important role in nociception.

In past decades, both prognosis and therapy of rectal cancer patients showed significant improvement, on the other hand, the incidence of rectal carcinoma continues to have a rising tendency. According to current UICC classification, patients in stage II rectal cancer or higher are indicated for neoadjuvant chemoradiotherapy (nCRT). Magnetic resonance imaging (MRI) is currently the most common diagnostic method used for preoperative staging of rectal cancer. Several studies already pointed out the inaccuracy of preoperative lymph node staging in patients with rectal cancer. The present study analyzed overall accuracy of MRI staging of rectal cancer and thus its accuracy in neoadjuvant therapy indication, by comparing preoperative MRI staging with definitive histopathologic results from resected tumors. This study evaluated cases of 92 patients with rectal tumor that underwent MRI examination followed by surgical resection. Tumors included in the analysis were ranging from T1 to T3b according to TNM staging, with free circumferential resection margin (CRM), distance form mesorectal fascia more than 5 mm, negative intersphincteric plane and also negative extramural venous invasion (EMVI), while the N stage was not decisive. In all cases both N-staging and T-staging were evaluated histologically and compared with preoperative MRI results. Significant difference in preoperative and postoperative N-staging was shown in 51 patients (61.45%). In majority of cases MRI lead to overstaging, which was observed in 44 cases (53.1 %), with complete negativity of lymph nodes proven by histological examination in 34 cases. On the other hand, understaging of lymph nodes was observed only in 7 cases (7.4 %). The T-staging did not show significant differences. Results from this study confirm that MRI plays an important role in T-staging of rectal tumors, however, there are admittedly issues in N-staging of tumors, which should lead to reevaluation of neoadjuvant therapy indication in patients with positive lymph nodes according to MRI examination. Based on the results of this study, we see the future of preoperative staging of rectal tumors in precise T-staging together with accurate assessment of CRM and distance of tumor from mesorectal fascia as well as evaluation of intersphinteric plane and EMVI.

Lamina I spino-parabrachial neurons (SPNs) receive peripheral nociceptive input, process it and transmit to the supraspinal centres. Although responses of SPNs to cutaneous receptive field stimulations have been intensively studied, the mechanisms of signal processing in these neurons are poorly understood. Therefore, we used an ex-vivo spinal cord preparation to examine synaptic and cellular mechanisms determining specific input-output characteristics of the neurons. The vast majority of the SPNs received a few direct nociceptive C-fiber inputs and generated one spike in response to saturating afferent stimulation, thus functioning as simple transducers of painful stimulus. However, 69% of afferent stimulation-induced action potentials in the entire SPN population originated from a small fraction (19%) of high-output neurons. These neurons received a larger number of direct Ad- and C-fiber inputs, generated intrinsic bursts and efficiently integrated a local network activity via NMDA-receptor-dependent mechanisms. The high-output SPNs amplified and integrated the nociceptive input gradually encoding its intensity into the number of generated spikes. Thus, different mechanisms of signal processing allow lamina I SPNs to play distinct roles in nociception. The authors thank Mr. Andrew Dromaretsky for the technical assistance. P.B. was supported by the National Academy of Sciences of Ukraine (NASU), grant NASU # 0116U004470, grant NASU#67/15-Н. N.V. was supported by the NASU Biotechnology and NASU-KNU grants; NIH 1R01NS113189-01. B.V.S. was supported by the FEDER funds through the COMPETE 2020 (POCI), Portugal 2020, and by the FCT project PTDC/NEU-NMC/1259/2014 (POCI-01-0145-FEDER-016588)

Objective The aim of this study was to evaluate the indication of neoadjuvant therapy in patients with middle and low rectal cancer based on MRI examination. Background In spite of noticeable advances in the diagnosis of rectal cancer, the optimal treatment remains highly debated. Current guidelines advise the use of neoadjuvant therapy in UICC stage II patients or higher. However, in clinical praxis, there is gradual implementation of new criterions and variables used in rectal cancer stage evaluation, the fact of which influences the treatment choice. The most important emerging variables taken currently into account are the distance from mesorectal fascia, circumferential resection margin, extramural venous invasion and intersphincteric plane, all of which can be evaluated using the MRI examination. Methods The accuracy of MRI staging was compared with definite histopathological results from resected tumors. Patient data were prospectively collected between the years 2013 and 2018 at 3rd Surgical Clinic, Faculty of Medicine, Comenius University in Bratislava, Slovakia. Data from 101 patients were gathered and divided into two groups, according to the localization of tumor within rectum, while 9 patients were excluded from the study because of benign lesion diagnosis based upon final histopathologic evaluation. Results In 92 evaluated patients, no significant change was noted between MRI and histopathological T-staging. However, in N-staging, significant differences were noted between preoperative MRI staging and postoperative histopathological staging. Conclusion The results of this study demonstrate inefficient preoperative lymph node staging, suggesting overtreatment of rectal cancer patients. Although the use of neoadjuvant therapy has led to great advances in modern cancer treatment, it is connected with a number of side effects and therefore should be indicated only for patients who can benefit from this treatment (Tab. 1, Fig. 3, Ref. 16).

Estimations of intracellular concentrations of fluorescently-labeled molecules within living cells are very important for guidance of biological experiments and interpretation of their results. Here we propose a simple and universal approach for such estimations. The approach is based upon common knowledge that the dye fluorescence is directly proportional to its quantum yield and the number of its molecules and that a coefficient of proportionality is determined by spectral properties of the dye and optical equipment used to record fluorescent signals. If two fluorescent dyes are present in the same volume, then a ratio of their concentrations is equal to a ratio of their fluorescence multiplied by some dye- and equipment-dependent coefficient. Thus, if the coefficient and concentration of one dye is known then the concentration of another dye can be determined. Here we have demonstrated how to calculate this coefficient (called a ratio factor) and how to use it for concentration measurements of fluorescently tagged molecules. As an example of how this approach can be used, we estimated a concentration of exogenously expressed neuronal Ca2+ sensor protein, hippocalcin, tagged by a fluorescent protein in a dendritic tree of rat hippocampal neurons loaded via a patch pipette with Alexa Fluor dye of known concentration. The new approach should allow performing a fast, inexpensive and reliable quantitative analysis of fluorescently-labeled targets in different parts of living cells.

After stimulation of GABA-ergic synaptic connections in a culture of hippocampal neurons by a series of depolarizing current pulses (5-45 sec-1, 5-20 stimuli), an inhibitory postsynaptic current (IPSC) consisting of a phasic component and an asynchronous component develops in the postsynaptic neuron. In experiments with simultaneous recording from two synapticaly connected neurons, we found that 2-min-long depolarization of the presynaptic cell to +40 mV also led to the development of the asynchronous IPSC component (аIPSC) induced by a single action potential (AP) in the presynaptic neuron. In this case, the decay time of IPSC was, on average, three times greater than in the first case. Analogous potentiation of аIPSC was observed in a part of the synaptic connections after their longlasting (15 min) stimulation by series of depolarizing current pulses (45 sec-1, 20 stimuli, betweenseries intervals 23 sec). Such potentiation of аIPSC was preserved for a long time (from 3 to 17 min). Simultaneously with potentiation of аIPSC, we observed potentiation of plateau-like inward current through the membrane of the presynaptic neuron in some synaptic connections. The charge transferred by this current through the membrane of the presynaptic cell correlated significantly with the decay time of evoked IPSC in the postsynaptic neuron (mean correlation coefficient 0.83±0.10). This fact can be considered an indication that the above-mentioned inward current mediates potentiation of the above IPSC. The obtained data allow us to hypothesize that the above-described form of plasticity can regulate the efficacy of GABA-ergic synaptic transmission in the hippocampus in the physiological modes of synaptic activity.

T-type Ca2+channels are known as important participants of nociception and their remodeling contributes to diabetes-induced alterations of pain sensation. In this work we have established that about 30% of rat nonpeptidergic thermal C-type nociceptive (NTCN) neurons of segments L4–L6 express a slow T-type Ca2+current (T-current) while a fast T-current is expressed in the other 70% of these neurons. Streptozotocin-induced diabetes in young rats resulted in thermal hyperalgesia, hypoalgesia, or normalgesia 5-6 weeks after the induction. Our results show that NTCN neurons obtained from hyperalgesic animals do not express the slow T-current. Meanwhile, the fraction of neurons expressing the slow T-current did not significantly change in the hypo- and normalgesic diabetic groups. Moreover, the peak current density of fast T-current was significantly increased only in the neurons of hyperalgesic group. In contrast, the peak current density of slow T-current was significantly decreased in the hypo- and normalgesic groups. Experimental diabetes also resulted in a depolarizing shift of steady-state inactivation of fast T-current in the hyperalgesic group and slow T-current in the hypo- and normalgesic groups. We suggest that the observed changes may contribute to expression of different types of peripheral diabetic neuropathy occurring during the development of diabetes mellitus.

Traditionally, collection of information from synaptic inputs distributed on dendrites and transmission of this information to the soma of the neuron were believed to be the only functions of these neuron compartments. In recent years, such a viewpoint was revised to a considerable extent due to novel results demonstrating that the dendrites can realize the role of structural/functional units or even complexes providing independent information processing and signaling via performing local computational operations. We propose a hypothesis that a dendrite segment, due to transient changes in the excitability of its membrane (provided by processes of postpolarizations after generation of action potentials and Hebbian-type plasticity of these processes) can play the role of a structural unit of memory. Namely, such a segment can recognize, memorize, and “forecast” sequences of input signals. A high capacity of such dendritic memory unit can be provided by the locality of electrical and corresponding biochemical processes in branches of the neuronal dendrite tree. Thus, a single dendrite segment can represent the relatively independent fundamental unit for signalization and integration in the nervous system.

Streptozotocin (STZ)-induced type 1 diabetes in rats leads to the development of peripheral diabetic neuropathy (PDN) manifested as thermal hyperalgesia at early stages (4th week) followed by hypoalgesia after 8weeks of diabetes development. Here we found that 6–7week STZ-diabetic rats developed either thermal hyper- (18%), hypo- (25%) or normalgesic (57%) types of PDN. These developmentally similar diabetic rats were studied in order to analyze mechanisms potentially underlying different thermal nociception. The proportion of IB4-positive capsaicin-sensitive small DRG neurons, strongly involved in thermal nociception, was not altered under different types of PDN implying differential changes at cellular and molecular level. We further focused on properties of T-type calcium and TRPV1 channels, which are known to be involved in Ca2+ signaling and pathological nociception. Indeed, TRPV1-mediated signaling in these neurons was downregulated under hypo- and normalgesia and upregulated under hyperalgesia. A complex interplay between diabetes-induced changes in functional expression of Cav3.2 T-type calcium channels and depolarizing shift of their steady-state inactivation resulted in upregulation of these channels under hyper- and normalgesia and their downregulation under hypoalgesia. As a result, T-type window current was increased by several times under hyperalgesia partially underlying the increased resting [Ca2+]i observed in the hyperalgesic rats. At the same time Cav3.2-dependent Ca2+ signaling was upregulated in all types of PDN. These findings indicate that alterations in functioning of Cav3.2 T-type and TRPV1 channels, specific for each type of PDN, may underlie the variety of pain syndromes induced by type 1 diabetes.

The data showing usefulness of navigated 3D–ultrasound (3DUS) during awake resections of eloquent gliomas are sparse. Results of surgeries performed using 3DUS were never compared to procedures guided by standard neuronavigation. The aim of this work is to assess the effectiveness of 3DUS during awake resections of eloquent low-grade gliomas (LGGs) by comparing surgical results of two series of patients operated on using conventional neuronavigation and using 3DUS. To our knowledge, a similar study is lacking in the literature. During a 4-year period (September 2006 to August 2010) 21 awake resections of LGGs guided by neuronavigation (series 1, S1) were consecutively performed in Department of Neurosurgery in Bratislava. During another 4-year period (August 2010 to July 2014) 28 awake resections of LGGs guided by 3DUS (series 2, S2) were consecutively conducted. In both patients series, the eloquent cortical and subcortical structures were intraoperatively detected by direct electrical stimulation. Extent of tumor resection (EOR) and functional outcome in both series were compared. EOR was significantly greater (p = 0.022) in S2 (median = 93.25%; mean = 86.79%), as compared to S1 (median 87.1%; mean = 75.85%). One permanent minor deficit in S1 and 2 minor deficits in S2 occurred, the difference was not significant (p = 0.999). Our work represents the first study comparing results of surgeries guided by 3DUS versus conventional navigation. The extent of awake resections of eloquent LGG guided by 3DUS was greater comparing to awake resections guided by standard neuronavigation; use of 3DUS had no impact on the number of new permanent deficits.

It was analyzed and identified clinico-pathomorphological features of papillary thyroid microcarcinoma (PTMC) concurrent with chronic lymphocytic thyroiditis (CLT). We found PTMC associated with CLT to have smaller size of carcinoma, significantly lower invasion to lymphatic vessels and capsule of thyroid gland as well as lower rate of metastases to local lymphonodules. Our results lead to conclusion that PTMC associated with CLT has lower level of biological aggressiveness. From these data we also hypothesize that CLT with may serve as a positive prognostic factor for patients with PTMC.

Hippocalcin is a Ca2+-binding protein that belongs to a family of neuronal Ca2+sensors and is a key mediator of many cellular functions including synaptic plasticity and learning. However, the molecular mechanisms involved in hippocalcin signalling remain illusive. Here we studied whether glutamate receptor activation induced by locally applied or synaptically released glutamate can be decoded by hippocalcin translocation. Local AMPA receptor activation resulted in fast hippocalcin-YFP translocation to specific sites within a dendritic tree mainly due to AMPA receptor-dependent depolarization and following Ca2+influx via voltage-operated calcium channels. Short local NMDA receptor activation induced fast hippocalcin-YFP translocation in a dendritic shaft at the application site due to direct Ca2+influx via NMDA receptor channels. Intrinsic network bursting produced hippocalcin-YFP translocation to a set of dendritic spines when they were subjected to several successive synaptic vesicle releases during a given burst whereas no translocation to spines was observed in response to a single synaptic vesicle release and to back-propagating action potentials. The translocation to spines required Ca2+influx via synaptic NMDA receptors in which Mg2+ block is relieved by postsynaptic depolarization. This synaptic translocation was restricted to spine heads and even closely (within 1–2 μm) located spines on the same dendritic branch signalled independently. Thus, we conclude that hippocalcin may differentially decode various spatiotemporal patterns of glutamate receptor activation into site- and time-specific translocation to its targets. Hippocalcin also possesses an ability to produce local signalling at the single synaptic level providing a molecular mechanism for homosynaptic plasticity.

Presented is the analysis of patients who underwent external beam radiotherapy (EBRT) to the brain in the period from 2003 to 2006 at the department of Radiation Oncology of the St. Elisabeth Cancer Institute.p align="justify"The aim of our analysis was to identify risk factors of late delayed therapy induced injuries (LDTI) in the brain. The patients were regularly examined with magnetic resonance (MRI), including conventional and advanced techniques: perfusion imaging (pMRI), diffusion weighted imaging (DWI), MRI spectroscopy (MRS). The results from MRI were correlated withsup18/supfluoro-deoxyglucose positron emission tomography (sup18/supFDG/PET) scans, as none of the listed method is sufficiently sensitive and specific by itself. Also clinical data records and treatment plans of these patients were analyzed./pp align="justify"In our cohort we found 6 patients with abnormal post-therapeutical changes, 4 of them with MR andsup18/supFDG/PET scans characteristics for LDTI - radiation necrosis. In one patient biopsy was performed and radiation necrosis (RN) was confirmed./pradiation necrosis, MRI, PET, 3D conformal radiotherapy (3D-CRT).

Hippocalcin is a Ca(2+)-binding protein, which belongs to the family of neuronal Ca(2+) sensors. It is highly expressed in the hippocampus but molecular mechanisms underlying its action in this part of the brain have not been investigated in detail. To study whether intrinsic neuronal activity could result in hippocalcin-mediated signal transduction we examined spontaneous and action potential (AP)-dependent changes in fluorescence of yellow fluorescent protein-tagged hippocalcin (HPCA-YFP) in transiently transfected hippocampal cultured neurons. In 6-12 DIV neurons HPCA-YFP spontaneously translocated longitudinally to specific sites within diffusionally confined domains of neuronal processes. The translocations to these sites were expressed as fast, reversible increases in HPCA-YFP fluorescence coincided with a decrease in adjacent sites indicating genuine protein translocation. Physiologically relevant neuronal stimulation with short trains of action potentials also resulted in fast, simultaneous, reversible, and [Ca(2+)](i)-dependent translocations of HPCA-YFP to several sites synchronizing hippocalcin signaling in different parts of neuronal processes. The amount of translocated protein increased with the number of action potentials in a train decoding the number of APs into the amount of translocated protein. We conclude that hippocalcin may signal within diffusionally restricted domains of neuronal processes in which it might play a physiological role in Ca(2+)-dependent local activation of specific molecular targets.

Pyramidal neurons of the hippocampus possess differential susceptibility to the ischemia-induced damage with the highest vulnerability of CA1 and the lower sensitivity of CA3 neurons. This damage is triggered by Ca(2+)-dependent excitotoxicity and can result in a delayed cell death that might be potentially suspended through activation of endogenous neuroprotection with the hypoxia-inducible transcription factors (HIF). However, the molecular mechanisms of this neuroprotection remain poorly understood. Here we show that prolonged (30min) oxygen and glucose deprivation (OGD) in situ impairs intracellular Ca(2+) regulation in CA1 rather than in CA3 neurons with the differently altered expression of genes coding Ca(2+)-ATPases: the mRNA level of plasmalemmal Ca(2+)-ATPases (PMCA1 and PMCA2 subtypes) was downregulated in CA1 neurons, whereas the mRNA level of the endoplasmic reticulum Ca(2+)-ATPases (SERCA2b subtype) was increased in CA3 neurons at 4h of re-oxygenation after prolonged OGD. These demonstrate distinct susceptibility of CA1 and CA3 neurons to the ischemic impairments in intracellular Ca(2+) regulation and Ca(2+)-ATPase expression. Stabilization of HIF-1α by inhibiting HIF-1α hydroxylation prevented the ischemic decrease in both PMCA1 and PMCA2 mRNAs in CA1 neurons, upregulated the SERCA2b mRNA level and eliminated the OGD-induced Ca(2+) store dysfunction in these neurons. Cumulatively, these findings reveal the previously unknown HIF-1α-driven upregulation of Ca(2+)-ATPases as a mechanism opposing the ischemic impairments in intracellular Ca(2+) regulation in hippocampal neurons. The ability of HIF-1α to modulate expression of genes coding Ca(2+)-ATPases suggests SERCA2b as a novel target for HIF-1 and may provide potential implications for HIF-1α-stabilizing strategy in activating endogenous neuroprotection.

1. The pathogenesis of diabetic neuropathy is a complex phenomenon, the mechanisms of which are not fully understood. Our previous studies have shown that the intracellular calcium signaling is impaired in primary and secondary nociceptive neurons in rats with streptozotocin (STZ)-induced diabetes. Here, we investigated the effect of prolonged treatment with the L-type calcium channel blocker nimodipine on diabetes-induced changes in neuronal calcium signaling and pain sensitivity. 2. Diabetes was induced in young rats (21 p.d.) by a streptozotocin injection. After 3 weeks of diabetes development, the rats were treated with nimodipine for another 3 weeks. The effect of nimodipine treatment on calcium homeostasis in nociceptive dorsal root ganglion neurons (DRG) and substantia gelatinosa (SG) neurons of the spinal cord slices was examined with fluorescent imaging technique. 3. Nimodipine treatment was not able to normalize elevated resting intracellular calcium ([Ca(2+)]( i )) levels in small DRG neurons. However, it was able to restore impaired Ca(2+) release from the ER, induced by either activation of ryanodine receptors or by receptor-independent mechanism in both DRG and SG neurons. 4. The beneficiary effects of nimodipine treatment on [Ca(2+)]( i ) signaling were paralleled with the reversal of diabetes-induced thermal hypoalgesia and normalization of the acute phase of the response to formalin injection. Nimodipine treatment was also able to shorten the duration of the tonic phase of formalin response to the control values. 5. To separate vasodilating effect of nimodipine Biessels et al., (Brain Res. 1035:86-93) from its effect on neuronal Ca(2+) channels, a group of STZ-diabetic rats was treated with vasodilator - enalapril. Enalapril treatment also have some beneficial effect on normalizing Ca(2+) release from the ER, however, it was far less explicit than the normalizing effect of nimodipine. Effect of enalapril treatment on nociceptive behavioral responses was also much less pronounced. It partially reversed diabetes-induced thermal hypoalgesia, but did not change the characteristics of the response to formalin injection. 6. The results of this study suggest that chronic nimodipine treatment may be effective in restoring diabetes-impaired neuronal calcium homeostasis as well as reduction of diabetes-induced thermal hypoalgesia and noxious stimuli responses. The nimodipine effect is mediated through a direct neuronal action combined with some vascular mechanism.

At present, there are no direct methods to determine the number of synaptic receptor-related channels activated in the course of synaptic transmission (N) or a value of the single-channel conductance (γ). Peak-scaled nonstationary fluctuation analysis (PS NSFA) should be considered the most well-developed indirect approach used for estimating these parameters. Despite the relatively wide using of this approach for the analysis of various synaptic currents, some aspects of possible errors that can occur in the course of data acquisition or their subsequent processing have not been studied. We examined in detail the problem of applicability of PS NSFA in the study of spontaneous and evoked GABA-ergic inhibitory postsynaptic currents (IPSCs). IPSCs were recorded using a dual patch-clamp technique from hippocampal neurons growing in low-density cultures. Parameters of the recorded IPSCs and values for different components of GABA-ergic synaptic transmission reported earlier were used for simulations and PS-NSFA analysis. In Monte Carlo computer simulations of evoked IPSCs, the influence of series resistance, background noise, asynchronicity of transmitter release, GABAA channel properties, dendritic attenuation, and instrumental filtering on γ estimates obtained by PS NSFA was examined. We concluded that the γ and, consequently, N values may be satisfactorily estimated by the suggested approach using spontaneous and evoked IPSCs recorded in inhibitory synaptic connections in hippocampal cultures within a wide range of experimental conditions. We also estimated the mean of the single-channel conductance of synaptic GABAA receptors in neurons from primary hippocampal cultures and found that this value (29 ± 5 pS) agrees well with the high conductance of single synaptic GABAA receptors observed in acute hippocampal slices. This indicates that dissociated cultures are an adequate model for studying the properties of synaptic GABAA receptors.

Based on the effect of prolonged tetanic stimulation (30 Hz, 4 sec), we divided GABAergic synaptic connections in hippocampal cell cultures into two groups: connections facilitated ( approximately 45%) and connections depressed ( approximately 55%) by the tetanic stimulation. In order to reveal possible reasons for the differential effect of the tetanization, we compared several properties of the connections belonging to both groups. We found that, on average, evoked IPSCs in the connections facilitated by the tetanization have a smaller amplitude and larger coefficient of variation (CV) of IPSC amplitude compared to connections depressed by the tetanization. We also estimated quantal parameters for both groups of connections assuming that transmitter release is reasonably described by a binomial distribution. We found that a background release probability (P) is substantially lower in the connections facilitated by the tetanization (P approximately 0.5) than in the connections depressed by the tetanization (P approximately 0.9) and suggest that this difference may underlie the differential effect of the tetanization. We also found that the tetanization induces the opposite effect on connections made by distinct presynaptic neurons with the same postsynaptic cell (convergent connections) in a fraction of postsynaptic neurons studied (3 out of 9). These results support the idea that properties of the presynaptic neuron are of primary importance for the observed differential effect of the tetanization, but they do not exclude a role of the postsynaptic neuron in this effect.

Persistent peripheral inflammation alters trafficking of AMPA receptors (AMPARs) at the synapses between primary afferents and dorsal horn (DH) neurons that contribute to the maintenance of inflammatory pain. However, whether peripheral inflammation changes the synaptic activity within the DH circuitry and how it modulates synaptic AMPARs in different neuronal types still remain unknown. We find that complete Freund adjuvant (CFA)-induced peripheral inflammation prominently augments excitatory neurotransmission in rat lamina II neurons characterized by intrinsic adapting firing properties and apparently decreases it in the tonic firing lamina II neurons, suggesting different roles of these types of interneurons in pain processing. Peripheral inflammation also differentially changes inhibitory neurotransmission in these neuronal types, shifting the balance between neuronal excitation and inhibition toward excitation of the adapting firing, but toward inhibition of the tonic firing lamina II neurons. Synaptic AMPARs were differentially changed in the adapting firing and the tonic firing neurons, implying different mechanisms of AMPAR adjustment at the synapses in these types of interneurons during persistent inflammation. The inflammatory-induced, neuron-type specific changes in synaptic drive within the DH circuitry and synaptic AMPAR functioning in lamina II neurons may contribute to the persistent pain maintenance.

Background Previous studies have shown that increased excitability of capsaicin-sensitive DRG neurons and thermal hyperalgesia in rats with short-term (2–4 weeks) streptozotocin-induced diabetes is mediated by upregulation of T-type Ca2+ current. In longer–term diabetes (after the 8th week) thermal hyperalgesia is changed to hypoalgesia that is accompanied by downregulation of T-type current in capsaicin-sensitive small-sized nociceptors. At the same time pain symptoms of diabetic neuropathy other than thermal persist in STZ-diabetic animals and patients during progression of diabetes into later stages suggesting that other types of DRG neurons may be sensitized and contribute to pain. In this study, we examined functional expression of T-type Ca2+ channels in capsaicin-insensitive DRG neurons and excitability of these neurons in longer-term diabetic rats and in thermally hypoalgesic diabetic rats. Results Here we have demonstrated that in STZ-diabetes T-type current was upregulated in capsaicin-insensitive low-pH-sensitive small-sized nociceptive DRG neurons of longer-term diabetic rats and thermally hypoalgesic diabetic rats. This upregulation was not accompanied by significant changes in biophysical properties of T-type channels suggesting that a density of functionally active channels was increased. Sensitivity of T-type current to amiloride (1 mM) and low concentration of Ni2+ (50 μM) implicates prevalence of Cav3.2 subtype of T-type channels in the capsaicin-insensitive low-pH-sensitive neurons of both naïve and diabetic rats. The upregulation of T-type channels resulted in the increased neuronal excitability of these nociceptive neurons revealed by a lower threshold for action potential initiation, prominent afterdepolarizing potentials and burst firing. Sodium current was not significantly changed in these neurons during long-term diabetes and could not contribute to the diabetes-induced increase of neuronal excitability. Conclusions Capsaicin-insensitive low-pH-sensitive type of DRG neurons shows diabetes-induced upregulation of Cav3.2 subtype of T-type channels. This upregulation results in the increased excitability of these neurons and may contribute to nonthermal nociception at a later-stage diabetes.

The effect of tetanic stimulation (30 Hz, 4 s) on evoked GABAergic inhibitory postsynaptic currents (IPSCs) was studied in cell cultures of dissociated hippocampal neurons with established synaptic connections. It was found that tetanic stimulation elicited post-tetanic depression (PTD) of the evoked IPSCs with a duration of more than 50 s in about 60% of the connections tested; post-tetanic potentiation was induced in 25% of the connections. We propose that the opposite effects of tetanization on IPSC amplitude are due to differences in the type of the interneuron that was tetanized. Since PTD in our experiments was usually accompanied by changes in the IPSC coefficient of variation and changes of a paired pulse depression, which are thought to reflect presynaptic mechanisms of modulation, we suggest that part of the PTD is due to a presynaptic mechanism(s).

During evoked release, several quanta of neurotransmitter are synchronously released in several GABA-ergic synapses. Assuming that not more than one vesicle is released at each release site, the decay of miniature and evoked IPSC (mIPSC and eIPSC, respectively) should coincide. In this study, we found that in a considerable part of the cultured hippocampal neurons eIPSC decayed more slowly than mIPSC did. We investigated the mechanisms underlying this difference using conventional electrophysiological approaches, deconvolution, simulations, and nonstationary noise analysis. Our results indicate that asynchronous release of synaptic vesicles cannot explain the prolonged decay of the GABA-ergic IPSC. We suggest that some interaction between the quanta at the pre- and/or post-synaptic level should result in a slower decay of the eIPSC in comparison with that of mIPSC.

The whole-cell patch-clamp technique was used to record monosynaptic inhibitory postsynaptic currents (IPSCs) from pairs of hippocampal neurons cultured for 2-3 weeks. The application of fresh physiological solution for 2-3 min reversibly reduced the amplitude of evoked GABAergic IPSCs to 72.5% of control value. The amplitude and frequency of spontaneous IPSCs decreased too. The depression of evoked IPSCs was significantly smaller or absent if conditioned solution was applied (physiological solution which had been previously in contact with neurons for 30 min). Currents evoked by exogenously applied GABA were unaffected by fresh solution. These results suggest that hippocampal neurons release some endogenous substance(s), by which they up regulate presynaptically their own inhibitory synaptic transmission.

In a dissociated culture of rat hippocampal neurons (14 to 24 daysin vitro), modulation effects of glutamate on GABAA-ergic inhibitory transmission were studied with the use of simultaneous patch-clamp whole-cell recording from monosynaptically connected neuron pairs. In all experiments (n=49), 1.5-min-long or longer extracellular application of 0.5 to 100 μM glutamate suppressed evoked inhibitory postsynaptic currents (IPSC). This suppression usually included fast (seconds) and slow (τ=1.3 min) phases. In 83.7% of the cases studied, IPSC did not return to the control values during the entire subsequent recording period (from 10 to 64 min). When glutamate was applied in the presence of blockers of glutamate ionotropic receptors, DL-APV or CNQX, the fast phase of the effect was removed, while some suppression of inhibitory neuronal responses, although weaker, was preserved (n=19); in most cases (73.3%) this residual suppression was slow and long-lasting. It is concluded that both types of glutamate receptors, ionotropic and metabotropic, are involved in modulation of GABAA-ergic synaptic transmission. The first above receptor type provides fast and reversible suppression, while the effect provided by the second type is slow and long-lasting.

Metallic plasma-facing components (PFCs) e.g. beryllium and tungsten, will be subjected to severe melting during plasma instabilities such as disruptions, edge-localized modes and high power excursions. Because of the greater thickness of the resulting melt layers relative to that of the surface vaporization, the potential loss of the developing melt-layer can significantly shorten PFC lifetime, severely contaminate the plasma and potentially prevent successful operation of the tokamak reactor. Mechanisms responsible for melt-layer loss during plasma instabilities are being modeled and evaluated. Of particular importance are hydrodynamic instabilities developed in the liquid layer due to various forces such as those from magnetic fields, plasma impact momentum, vapor recoil and surface tension. Another mechanism found to contribute to melt-layer splashing loss is volume bubble boiling, which can result from overheating of the liquid layer. To benchmark these models, several new experiments were designed and performed in different laboratory devices for this work; the results are examined and compared. Theoretical predictions (A ∗ THERMAL-S and SPLASH codes) are generally in good agreement with the experimental results. The effect of in-reactor disruption conditions, which do not exist in simulation experiments, on melt-layer erosion is discussed.

T-type Ca2+ channels are known as important participants of nociception and their remodeling contributes to diabetes-induced alterations of pain sensation. In this work we have established that about 30% of rat nonpeptidergic thermal C-type nociceptive (NTCN) neurons of segments L4–L6 express a slow T-type Ca2+ current (T-current) while a fast T-current is expressed in the other 70% of these neurons. Streptozotocin-induced diabetes in young rats resulted in thermal hyperalgesia, hypoalgesia, or normalgesia 5-6 weeks after the induction. Our results show that NTCN neurons obtained from hyperalgesic animals do not express the slow T-current. Meanwhile, the fraction of neurons expressing the slow T-current did not significantly change in the hypo- and normalgesic diabetic groups. Moreover, the peak current density of fast T-current was significantly increased only in the neurons of hyperalgesic group. In contrast, the peak current density of slow T-current was significantly decreased in the hypo- and normalgesic groups. Experimental diabetes also resulted in a depolarizing shift of steady-state inactivation of fast T-current in the hyperalgesic group and slow T-current in the hypo- and normalgesic groups. We suggest that the observed changes may contribute to expression of different types of peripheral diabetic neuropathy occurring during the development of diabetes mellitus.

Patterns of short-term synaptic plasticity could considerably differ between synapses of the same axon. This may lead to separation of synaptic receptors transmitting either low- or high-frequency signals and, therefore, may have functional consequences for the information transfer in the brain. Here, we estimated a degree of such separation at hippocampal GABAergic synapses using a use-dependent GABAA receptor antagonist, picrotoxin, to selectively suppress a pool of GABAA receptors monosynaptically activated during the low-frequency stimulation. The relative changes in postsynaptic responses evoked by the high-frequency stimulation before and after such block were used to estimate the contribution of this GABAA receptor pool to synaptic transmission at high frequencies. Using this approach, we have shown that IPSCs evoked by low-frequency (0.2 Hz) stimulation and asynchronous currents evoked by high-frequency (20-40 Hz) stimulation are mediated by different pools of postsynaptic GABAA receptors. Thus, our findings suggest that inhibition produced by a single hippocampal interneuron may be selectively routed to different postsynaptic targets depending on the presynaptic discharge frequency.

The postoperative biological behavior of nonfunctioning pituitary adenomas (NFPAs) is variable. Some residual NFPAs are stable long-term, others grow, and some recur despite complete removal. The usual histological markers of tumor aggressiveness are often similar between recurring, regrowing, and stable tumors, and therefore are not reliable as prognostic parameters. In this study, the clinical utility of proliferation indices (labeling index, Li) based on immunohistochemistry targeted at antigens Ki-67 and High-mobility group A1 (HMGA-1) for prediction of NFPA prognosis was investigated.Fifty patients with NFPAs were investigated. In each patient, Ki-67 and HMGA-1 Li were evaluated. Based on postoperative magnetic resonance images, patients were classified as tumor-free (18 patients), or harboring a residual tumor (32 patients). The latter group was further subdivided into groups with stable tumor remnants (11 patients) or progressive tumor remnants (21 patients).The median follow-up period was 8 years. No significant relationship between HMGA-1 Li and residual tumor growth was found. Growing residual tumors showed a trend towards higher Ki-67 Li compared with stable ones (p = 0.104). All tumor remnants with Ki-67 Li above 2.2% were growing. The relationship between residual tumor growth and Ki-67 Li exceeding the cutoff value of 2.2% was significant (p = 0.01 in univariate, p = 0.044 in multivariate analysis).The prognostic significance of the HMGA-1 antigen was not confirmed. In contrast, the Ki-67 Li provides useful and valuable information for the postoperative management of NFPAs. In residual adenomas with a Ki-67 Li above 2.2%, regrowth should be expected, and these tumors may require shorter intervals of follow-up magnetic resonance imaging (MRI) and/or early adjuvant therapy. Future larger studies are needed to confirm the results of this study.

This paper contains a description of a new method designed to monitor the distribution of Ca2+ efflux from cells or small cellular aggregates. The idea behind this method is to use a fluorescent Ca2+ indicator bound to dextrans of high molecular weight to slow down Ca2+ diffusion. Due to the decrease in diffusion rate, Ca2+ ions should be held close to the site of their release from the cells for a relatively long time, enough for the confocal microscope to detect such a local increase in Ca2+ concentration. This paper gives a detailed description of the method, illustrated with results of measurements of agonist-dependent and agonist-independent Ca2+ extrusion from pancreatic acinar cells. An appendix provides the mathematical background that should allow selection of the concentration of buffer which is necessary to achieve a particular Ca2+ diffusion coefficient.

A mathematical model evaluating the changes in the concentration of free extracellular calcium ([Ca2+]) as a function of time and radial distance from a spherical cell following uniform calcium release across its external membrane was developed. The space of extracellular solution was represented as concentric shells of uniform thickness. Two simplified approaches were used, which allowed us to describe calcium diffusion and buffering in each extracellular shell by only a single differential equation. The possibility of simulating the spatio-temporal [Ca2+] distribution in the case of uniformly located calcium pumps was demonstrated. Developed for pancreatic acinar cells, our model can be also used for studying ion release from other cells under similar experimental conditions and for reconstruction of ion fluxes in the presence of different fluorescent dyes.

In pancreatic acinar cells low (physiological) agonist concentrations evoke cytosolic Ca2+ spikes specifically in the apical secretory pole that contains a high density of secretory (zymogen) granules (ZGs). Inositol 1,4,5-trisphosphate (IP3) is believed to release Ca2+ from the endoplasmic reticulum, but we have now tested whether the Ca2+-releasing messengers IP3 and cyclic ADP-ribose (cADPr) can liberate Ca2+ from ZGs. In experiments on single isolated ZGs, we show using confocal microscopy that IP3 and cADPr evoke a marked decrease in the free intragranular Ca2+ concentration. Using a novel high resolution method, we have measured changes in the Ca2+ concentration in the vicinity of an isolated ZG and show that IP3 and cADPr cause rapid Ca2+ release from the granule, explaining the agonist-evoked cytosolic Ca2+ rise in the secretory pole.

Intersectin 1 (ITSN1) is a multidomain adaptor protein that functions in clathrin-mediated endocytosis and signal transduction. This protein is highly abundant in neurons and is implicated in Down syndrome, Alzheimer's disease and, possibly, other neurodegenerative disorders. Here we used an in vitro binding assay combined with MALDI-TOF mass spectrometry to identify novel binding partners of ITSN1. We found that the neuron-specific isoform of the stable tubule-only polypeptide (STOP) interacts with SH3A domain of ITSN1. STOP and ITSN1 were shown to form a complex in vivo and to partially co-localize in rat primary hippocampal neurons. As STOP is a microtubule-stabilizing protein that is required for several forms of synaptic plasticity in the hippocampus, identification of this interaction raises the possibility of ITSN1 participation in this process.

Persistent inflammation promotes internalization of synaptic GluR2-containing, Ca 21 -im- permeable AMPA receptors (AMPARs) and insertion of GluR1-containing, Ca 21 -permeable AMPARs at extrasynaptic sites in dorsal horn neurons. Previously we have shown that internalization of synaptic GluR2-containing AMPARs requires activation of spinal cord protein kinase C alpha (PKCa), but mo- lecular mechanisms that underlie altered trafficking of extrasynaptic AMPARs are unclear. Here, using antisense (AS) oligodeoxynucleotides (ODN) that specifically knock down PKCa, we found that a de- crease in dorsal horn PKCa expression prevents complete Freund's adjuvant (CFA)-induced increase in functional expression of extrasynaptic Ca 21 -permeable AMPARs in substantia gelatinosa (SG) neu- rons of the rat spinal cord. Augmented AMPA-induced currents and associated (Ca 21 )i transients were abolished, and the current rectification 1 day post-CFA was reversed. These changes were ob- served specifically in SG neurons characterized by intrinsic tonic firing properties, but not in those that exhibited strong adaptation. Finally, dorsal horn PKCa knockdown produced an antinociceptive effect on CFA-induced thermal and mechanical hypersensitivity during the maintenance period of in- flammatory pain, indicating a role for PKCa in persistent inflammatory pain maintenance. Our results indicate that inflammation-induced trafficking of extrasynaptic Ca 21 -permeable AMPARs in tonically firing SG neurons depends on PKCa, and that this PKCa-dependent trafficking may contribute to per- sistent inflammatory pain maintenance. Perspective: This study shows that PKCa knockdown blocks inflammation-induced upregulation of extrasynaptic Ca 21 -permeable AMPARs in dorsal horn neurons and produces an antinociceptive ef- fect during the maintenance period of inflammatory pain. These findings have potential implications for use of PKCa gene-silencing therapy to prevent and/or treat persistent inflammatory pain.

Persistent peripheral inflammation changes AMPA receptor (AMPAR) trafficking in dorsal horn neurons by promoting internalization of GluR2-containing, Ca(2+)-impermeable AMPARs from the synapses and by increasing insertion of GluR1-containing, Ca(2+)-permeable AMPARs in extrasynaptic plasma membrane. These changes contribute to the maintenance of persistent inflammatory pain. However, much less is known about AMPAR trafficking during development of persistent inflammatory pain and direct studies of extrasynaptic AMPARs functioning during this period are still lacking. Using Complete Freund's adjuvant (CFA)-induced model of long-lasting peripheral inflammation, we showed that remarkable hyperalgesia and allodynia developes in 1-3 h after intraplantar CFA injection. By utilizing patch-clamp recording combined with Ca(2+) imaging, we found a significant upregulation of extrasynaptic AMPARs in substantia gelatinosa (SG) neurons of the rat spinal cord 2-3 h after CFA injection. This upregulation was manifested as a robust increase in the amplitude of AMPAR-mediated currents 2-3 h post-CFA. These changes were observed specifically in SG neurons characterized by intrinsic tonic firing properties, but not in those that exhibited strong adaptation. Our results indicate that CFA-induced inflammation increases functional expression of extrasynaptic AMPARs in tonically firing SG neurons during development of pain hypersensitivity and that this increase may contribute to the development of peripheral persistent pain.

A new method is described that accurately estimates kinetic constants, conductance and number of ion channels from macroscopic currents. The method uses both the time course and the strength of correlations between different time points of macroscopic currents and utilizes the property of semiseparability of covariance matrix for computationally efficient estimation of current likelihood and its gradient. The number of calculation steps scales linearly with the number of channel states as opposed to the cubic dependence in a previously described method. Together with the likelihood gradient evaluation, which is almost independent of the number of model parameters, the new approach allows evaluation of kinetic models with very complex topologies. We demonstrate applicability of the method to analysis of synaptic currents by estimating accurately rate constants of a 7-state model used to simulate GABAergic macroscopic currents.

Introduction: The therapeutic procedures in the management of testicular cancer are determined by histological findings in the removed testis and by the extent of the disease at the time of diagnosis. However, all advanced tumors could be treated by primary chemotherapy regardless of the histological findings. The current imaging techniques (ultrasound of the testis, abdominal and chest CT examination) and laboratory tests (determination of serum tumor markers AFP and hCG) provide sufficient evidence for the presence of cancer. When the diagnosis of advanced tumor is evident, it is possible to start the treatment without orchiectomy. The aim of this study was to evaluate the advantages of neo-adjuvant chemotherapy with delayed orchiectomy in the management of advanced testicular cancer. Material and methods: A total of 36 patients with advanced germ cell testicular cancer underwent primary PVB or BEP chemotherapy without previous orchiectomy. Mean age of patients was 32 years. Detailed medical, surgical and urological examination showed pulmonary metastases and/or extensive abdominal tumorous masses imitating acute abdominal crisis and impaired drainage of the kidney due to ureteral obstruction. Searching for the origin, testicular tumor was detected. Eleven patients had a bulky disease in the retroperitoneum (Stage IIC), two had enlarged retroperitoneal lymph nodes (Stage IIB), two had enlarged mediastinal lymph nodes (Stage III) and other 16 patients had also pulmonary metastases, and 5 pts had pulmonary metastases only. The patients were treated with cisplatin-containing combination chemotherapy. Following completion of chemotherapy, orchiectomy was performed alone or simultaneously with retroperitoneal lymph node dissection (RPLND) and/or lung metastasectomy in cases with persistent residual mass. Following orchiectomy the patients were regularly checked and in cases with viable malignant tumor found in the testis sequential chemotherapy was administered. Similarly when the relapse of the disease was detected, the patients were treated with sequential chemotherapy. Results: Complete disappearance of metastases was observed in 12 patients following chemotherapy alone. The residual mass persisted in 24 patients (in 22 out of them in the retroperitoneum and in two patients also in the lungs) and was removed surgically. The viable tumor in the removed tissue was found in one patient. Delayed orchiectomy was performed simultaneously with surgical removal of residual mass in the retroperitoneum in 24 patients and as a separate procedure in 12 patients who have been considered to be complete responders following chemotherapy alone. Residual viable tumor in testicular specimen was found in three patients, necrotic or fibrotic tissue in 18, and mature teratoma in 15 patients. Overall survival of the patients was 26/36 (72.7%) at mean of 56.9 months (range 7–145 months, median 50 months) since the start of the treatment. Conclusions: In patients with advanced germ cell testicular cancer preference must be given to the early beginning of intensive chemotherapy without the need of tissue diagnosis of primary tumor that should be obtained by orchiectomy. Benefit of this therapeutic approach is the timely management of acute abdominal and/or pulmonary symptoms of life-threatening distant metastases.

Impaired insulin action, frequently found in essential hypertension (HT), is modified by other factors, such as higher age, accumulation of body fat, dyslipidaemia, impaired glucose metabolism and endothelial dysfunction. In addition, antihypertensive and insulin-sensitizing medication itself may significantly affect cardiovascular and metabolic milieu. The aim of this study was to assess insulin sensitivity, acute insulin response, lipidaemic status and the adipokines' concentrations with regard to abdominal fat distribution in young, lean male subjects with treatment-naïve essential HT and in matched healthy normotensive (NT) subjects. We studied 27 HT patients (age: 19.9±0.6 years; body mass index (BMI): 22.9±0.5 kg m(-2)) and 15 NT controls (age: 22.3±1.0 years; BMI: 23.7±0.6 kg m(-2)). The subjects underwent an oral and an intravenous glucose tolerance test (OGTT, IVGTT) on separate days in random order. Higher fasting insulin (P0.001), non-esterified fatty acids (P0.05) and plasminogen activator inhibitor factor 1 concentrations (P0.05) were found in HT patients when compared with NT patients. Despite comparable anthropometric parameters and body fat distribution assessed by magnetic resonance imaging in both groups, newly diagnosed untreated young hypertensive male subjects showed decreased insulin sensitivity, augmented insulin response to both oral and intravenous glucose load (P0.01; P0.05 respectively) and 'higher still normal' 2-h plasma glucose levels during OGTT. Untreated, young, lean hypertensive male subjects, with distribution of abdominal adipose tissue and lipid profile comparable with their healthy NT matched counterparts, showed considerable signs of insulin resistance and hyperinsulinaemia. We hypothesize that insulin resistance is the initial feature, which is influenced by several environmental factors, and HT is one of their common consequences.