90 research outputs found
The Increased Activity of TRPV4 Channel in the Astrocytes of the Adult Rat Hippocampus after Cerebral Hypoxia/Ischemia
The polymodal transient receptor potential vanilloid 4 (TRPV4) channel, a member of the TRP channel family, is a calcium-permeable cationic channel that is gated by various stimuli such as cell swelling, low pH and high temperature. Therefore, TRPV4-mediated calcium entry may be involved in neuronal and glia pathophysiology associated with various disorders of the central nervous system, such as ischemia. The TRPV4 channel has been recently found in adult rat cortical and hippocampal astrocytes; however, its role in astrocyte pathophysiology is still not defined. In the present study, we examined the impact of cerebral hypoxia/ischemia (H/I) on the functional expression of astrocytic TRPV4 channels in the adult rat hippocampal CA1 region employing immunohistochemical analyses, the patch-clamp technique and microfluorimetric intracellular calcium imaging on astrocytes in slices as well as on those isolated from sham-operated or ischemic hippocampi. Hypoxia/ischemia was induced by a bilateral 15-minute occlusion of the common carotids combined with hypoxic conditions. Our immunohistochemical analyses revealed that 7 days after H/I, the expression of TRPV4 is markedly enhanced in hippocampal astrocytes of the CA1 region and that the increasing TRPV4 expression coincides with the development of astrogliosis. Additionally, adult hippocampal astrocytes in slices or cultured hippocampal astrocytes respond to the TRPV4 activator 4-alpha-phorbol-12,-13-didecanoate (4αPDD) by an increase in intracellular calcium and the activation of a cationic current, both of which are abolished by the removal of extracellular calcium or exposure to TRP antagonists, such as Ruthenium Red or RN1734. Following hypoxic/ischemic injury, the responses of astrocytes to 4αPDD are significantly augmented. Collectively, we show that TRPV4 channels are involved in ischemia-induced calcium entry in reactive astrocytes and thus, might participate in the pathogenic mechanisms of astroglial reactivity following ischemic insult
Distinct Expression/Function of Potassium and Chloride Channels Contributes to the Diverse Volume Regulation in Cortical Astrocytes of GFAP/EGFP Mice
Recently, we have identified two astrocytic subpopulations in the cortex of GFAP-EGFP mice, in which the astrocytes are visualized by the enhanced green–fluorescent protein (EGFP) under the control of the human glial fibrillary acidic protein (GFAP) promotor. These astrocytic subpopulations, termed high response- (HR-) and low response- (LR-) astrocytes, differed in the extent of their swelling during oxygen-glucose deprivation (OGD). In the present study we focused on identifying the ion channels or transporters that might underlie the different capabilities of these two astrocytic subpopulations to regulate their volume during OGD. Using three-dimensional confocal morphometry, which enables quantification of the total astrocytic volume, the effects of selected inhibitors of K+ and Cl− channels/transporters or glutamate transporters on astrocyte volume changes were determined during 20 minute-OGD in situ. The inhibition of volume regulated anion channels (VRACs) and two-pore domain potassium channels (K2P) highlighted their distinct contributions to volume regulation in HR-/LR-astrocytes. While the inhibition of VRACs or K2P channels revealed their contribution to the swelling of HR-astrocytes, in LR-astrocytes they were both involved in anion/K+ effluxes. Additionally, the inhibition of Na+-K+-Cl− co-transporters in HR-astrocytes led to a reduction of cell swelling, but it had no effect on LR-astrocyte volume. Moreover, employing real-time single-cell quantitative polymerase chain reaction (PCR), we characterized the expression profiles of EGFP-positive astrocytes with a focus on those ion channels and transporters participating in astrocyte swelling and volume regulation. The PCR data revealed the existence of two astrocytic subpopulations markedly differing in their gene expression levels for inwardly rectifying K+ channels (Kir4.1), K2P channels (TREK-1 and TWIK-1) and Cl− channels (ClC2). Thus, we propose that the diverse volume changes displayed by cortical astrocytes during OGD mainly result from their distinct expression patterns of ClC2 and K2P channels
Acute kidney injury in patients treated with immune checkpoint inhibitors
Background: Immune checkpoint inhibitor-associated acute kidney injury (ICPi-AKI) has emerged as an important toxicity among patients with cancer. Methods: We collected data on 429 patients with ICPi-AKI and 429 control patients who received ICPis contemporaneously but who did not develop ICPi-AKI from 30 sites in 10 countries. Multivariable logistic regression was used to identify predictors of ICPi-AKI and its recovery. A multivariable Cox model was used to estimate the effect of ICPi rechallenge versus no rechallenge on survival following ICPi-AKI. Results: ICPi-AKI occurred at a median of 16 weeks (IQR 8-32) following ICPi initiation. Lower baseline estimated glomerular filtration rate, proton pump inhibitor (PPI) use, and extrarenal immune-related adverse events (irAEs) were each associated with a higher risk of ICPi-AKI. Acute tubulointerstitial nephritis was the most common lesion on kidney biopsy (125/151 biopsied patients [82.7%]). Renal recovery occurred in 276 patients (64.3%) at a median of 7 weeks (IQR 3-10) following ICPi-AKI. Treatment with corticosteroids within 14 days following ICPi-AKI diagnosis was associated with higher odds of renal recovery (adjusted OR 2.64; 95% CI 1.58 to 4.41). Among patients treated with corticosteroids, early initiation of corticosteroids (within 3 days of ICPi-AKI) was associated with a higher odds of renal recovery compared with later initiation (more than 3 days following ICPi-AKI) (adjusted OR 2.09; 95% CI 1.16 to 3.79). Of 121 patients rechallenged, 20 (16.5%) developed recurrent ICPi-AKI. There was no difference in survival among patients rechallenged versus those not rechallenged following ICPi-AKI. Conclusions: Patients who developed ICPi-AKI were more likely to have impaired renal function at baseline, use a PPI, and have extrarenal irAEs. Two-thirds of patients had renal recovery following ICPi-AKI. Treatment with corticosteroids was associated with improved renal recovery
The evidence base for circulating tumour DNA blood-based biomarkers for the early detection of cancer: a systematic mapping review
Background: The presence of circulating cell-free DNA from tumours in blood (ctDNA) is of major importance to those interested in early cancer detection, as well as to those wishing to monitor tumour progression or diagnose the presence of activating mutations to guide treatment. In 2014, the UK Early Cancer Detection Consortium undertook a systematic mapping review of the literature to identify blood-based biomarkers with potential for the development of a non-invasive blood test for cancer screening, and which identified this as a major area of interest. This review builds on the mapping review to expand the ctDNA dataset to examine the best options for the detection of multiple cancer types. Methods: The original mapping review was based on comprehensive searches of the electronic databases Medline, Embase, CINAHL, the Cochrane library, and Biosis to obtain relevant literature on blood-based biomarkers for cancer detection in humans (PROSPERO no. CRD42014010827). The abstracts for each paper were reviewed to determine whether validation data were reported, and then examined in full. Publications concentrating on monitoring of disease burden or mutations were excluded. Results: The search identified 94 ctDNA studies meeting the criteria for review. All but 5 studies examined one cancer type, with breast, colorectal and lung cancers representing 60% of studies. The size and design of the studies varied widely. Controls were included in 77% of publications. The largest study included 640 patients, but the median study size was 65 cases and 35 controls, and the bulk of studies (71%) included less than 100 patients. Studies either estimated cfDNA levels non-specifically or tested for cancer-specific mutations or methylation changes (the majority using PCR-based methods). Conclusion: We have systematically reviewed ctDNA blood biomarkers for the early detection of cancer. Pre-analytical, analytical, and post-analytical considerations were identified which need to be addressed before such biomarkers enter clinical practice. The value of small studies with no comparison between methods, or even the inclusion of controls is highly questionable, and larger validation studies will be required before such methods can be considered for early cancer detection
Ocrelizumab versus Interferon Beta-1a in Relapsing Multiple Sclerosis
Supported by F. Hoffmann–La Roche
Інновації та туристичні регіони: чи розглядають інновації як детермінанту розвитку в європейського туризму в регіонах?
У статті проаналізовано інноваційні аспекти розвитку туристичних регіонів у Європі. Основною метою статті
є визначення ступеня сприйняття інновацій у туристичних регіонах як детермінанти їх розвитку. Авторами
оцінено проблему розвитку туристичних регіонів у Європі у сфері інновацій, як можливого вихідного пункту
для оптимізації змін у політиці місцевого та регіонального туризму. Вихідну базу дослідження сформовано на
основі опитування 95 експертів у галузі регіонального туризму з 17 країн Європи. Для аналізу властивостей
категоріальних даних та їх взаємозв'язків використано статистичні методи, такі як Gamma, Kendall's Tau-b,
Somers' D C|R, коефіцієнт кореляції Спірмена, Коефіцієнт Фі, Коефіцієнт Контингентності, Коефіцієнт Крамера,
а також алгоритм дерева рішень. Рівень інноваційного середовища у туристичних регіонах та їхня ступінь
розвитку впливають на сприйняття інновацій. Регіони Південної Європи сприймають інновації як найбільш
ефективний інструмент, що формує передумови їх розвитку. Туристичні регіони з вищим рівнем інноваційної
активності мають встановлену систему управління якістю, а також комплексний і систематичний підхід до
постачання продуктів як у сезонний, так і позасезонний періоди. Регіони, що віднесені до групи "Емерджентних
інноваторів", виявляють більш інтенсивне сприйняття проблем у впровадженні інновацій. Це відображає
недостатню координацію портфеля замовлень як за обсягом, так і за якістю, в країнах, де інноваційне середовище
слабо розвинене. Головною рекомендацією для зменшення сприйняття інновацій як проблеми у розвитку
туристичних регіонів Європи є акцент на впровадженні інструментів регіональної політики, які стимулюють
участь туризму в синергетичних ефектах існуючого інноваційного середовища економіки.This article examines innovative aspects of the development of tourism regions in Europe. The
article aims to determine the intensity of the perception of innovation in the tourism region as a problem in
its development. The ambition of the article is to assess the problems in the development of tourism regions
in Europe in the field of innovation as a possible starting point for optimizing changes in local and regional
tourism policy. The research analyses the positions of 95 regional tourism experts from 17 European
countries. The database was based on a databank of 150 representatives of academia and 275 representatives
of regional tourism organizations. To analyse the properties of categorical data and the relationships between
them, we used Gamma, Kendall's Tau-b, Somers' D C|R, Spearman correlation coefficient, Phi Coefficient,
Contingency Coefficient, Cramer's V and the decision tree algorithm. The maturity of the innovation
environment of tourism regions and their level of development influence the perception of innovations as a
problem in their development. Southern European tourism regions perceive innovation as a problem in their
development most intensively. Tourism regions with stronger innovation activity have a well-established
quality management system and a comprehensive and systematically addressed supply of seasonal and offseason products. Tourism regions ranked in the emerging innovator group perceive the specified problems in
the implementation of innovations more intensively. This reflects the lack of coordination of the product
portfolio, both in terms of range and quality, in countries where the innovation environment is poorly
developed. A key recommendation to mitigate the perception of innovations as a problem in the development
of Europe's tourism regions is to focus attention on the implementation of regional policy instruments that
stimulate the participation of tourism in the synergy effects of the existing innovation environment of the
economy
Atresia of right pulmonary veins and anomalous left pulmonary venous drainage into portal circulation
Flora of toxic depots in selected industrial zones
Floristic composition in three industrial areas with soils contaminated by heavy metals (As, Cd, Cu, Hg, Pb, Zn) and organic pollutants (polychlorinated biphenyls) was studied. The content of Pb was only significantly correlated with the floristic composition and explained 13.8% of its variability considering spatial dependency of the sites. No correlation was found for PCBs. Altogether, 237 plant vascular species were found at three study sites (117, 133 and 105, respectively). The three study areas differed in their species composition represented by their own characteristic species. The gradient in the content of natives/non-natives, species number, prevailing life forms and indicator values for plant species investigated was revealed. Based on our results, for phytoremediation purposes we can select productive plant species with high biomass and ability to accumulate large amounts of heavy metals or organic compounds and surviving on soils with low mineral content
Vergleichende Analyse des Serum-Metaboloms von SpA- und SLE-Patienten mit und ohne koinzidenter Krebserkrankung
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