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31.
Ferenc Tóth Mikko J. Nissi Jinjin Zhang Michael Benson Sebastian Schmitter Jutta M. Ellermann Cathy S. Carlson 《Journal of orthopaedic research》2013,31(12):2006-2012
Cartilage canal vessels in epiphyseal cartilage have a pivotal role in the pathogenesis of osteochondrosis/osteochondritis dissecans. The present study aimed to validate high field magnetic resonance imaging (MRI) methods to visualize these vessels in young pigs. Osteochondral samples from the distal femur and distal humerus (predilection sites of osteochondrosis) of piglets were imaged post‐mortem: (1) using susceptibility‐weighted imaging (SWI) in an MRI scanner, followed by histological evaluation; and (2) after barium perfusion using µCT, followed by clearing techniques. In addition, both stifle joints of a 25‐day‐old piglet were imaged in vivo using SWI and gadolinium enhanced T1‐weighted MRI, after which distal femoral samples were harvested and evaluated using µCT and histology. Histological sections were compared to corresponding MRI slices, and three‐dimensional visualizations of vessels identified using MRI were compared to those obtained using µCT and to the cleared specimens. Vessels contained in cartilage canals were identified using MRI, both ex vivo and in vivo; their locations matched those observed in the histological sections, µCT images, and cleared specimens of barium‐perfused tissues. The ability to visualize cartilage canal blood vessels by MRI, without using a contrast agent, will allow future longitudinal studies to evaluate their role in developmental orthopedic disease. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:2006–2012, 2013 相似文献
32.
Tatsuro Misu Romana Höftberger Kazuo Fujihara Isabella Wimmer Yoshiki Takai Shuhei Nishiyama Ichiro Nakashima Hidehiko Konno Monika Bradl Ferenc Garzuly Yasuto Itoyama Masashi Aoki Hans Lassmann 《Acta neuropathologica》2013,125(6):815-827
Neuromyelitis optica (NMO) is an autoimmune disease targeting aquaporin 4 (AQP4), localized mainly at the astrocytic foot processes. Loss of AQP4 and glial fibrillary acidic protein (GFAP) was reported, but the pathological significance of astrocytopathy is still controversial. Here we show that active lesions in NMO display a wide spectrum of pathology even within a single tissue block of an individual patient. We have distinguished six different lesion types. The first reflects complement deposition at the surface of astrocytes, associated with granulocyte infiltration and astrocyte necrosis and followed by demyelination, global tissue destruction and the formation of cystic, necrotic lesions (lesion type 2). Such destructive lesions lead to Wallerian degeneration in lesion-related tracts (lesion type 3). Around active NMO lesions AQP4 may selectively be lost in the absence of aquaporin 1 (AQP1) loss or other structural damage (lesion type 4). Another pattern is characterized by clasmatodendrosis of astrocytes, defined by cytoplasmic swelling and vacuolation, beading and dissolution of their processes and nuclear alterations resembling apoptosis, which was associated with internalization of AQP4 and AQP1 and astrocyte apoptosis in the absence of complement activation. Such lesions give rise to extensive astrocyte loss, which may occur in part in the absence of any other tissue injury, such as demyelination or axonal degeneration (lesion type 5). Finally, lesions with a variable degree of astrocyte clasmatodendrosis are found, which show plaque-like primary demyelination that is associated with oligodendrocyte apoptosis, but with preservation of axons (lesion type 6). In active multiple sclerosis (MS) lesions astrocytes reveal changes of reactive protoplasmatic or fibrillary gliosis. Only in a subset of lesions, in patients with aggressive disease, loss of AQP4 is observed in the initial stage of their formation, which is associated with retraction of astrocyte processes in the absence of complement deposition, granulocyte infiltration or loss of AQP1 or astrocytes. Our data underline the primary assault of astrocytes in NMO lesions, but also indicate that different mechanisms of tissue injury operate in parallel in the same patient and even within the same lesion. 相似文献
33.
Peter Toth Zsuzsanna Tucsek Danuta Sosnowska Tripti Gautam Matthew Mitschelen Stefano Tarantini Ferenc Deak Akos Koller William E Sonntag Anna Csiszar Zoltan Ungvari 《Journal of cerebral blood flow and metabolism》2013,33(11):1732-1742
Hypertension in the elderly substantially contributes to cerebromicrovascular damage and promotes the development of vascular cognitive impairment. Despite the importance of the myogenic mechanism in cerebromicrovascular protection, it is not well understood how aging affects the functional adaptation of cerebral arteries to high blood pressure. Hypertension was induced in young (3 months) and aged (24 months) C57/BL6 mice by chronic infusion of angiotensin II (AngII). In young hypertensive mice, the range of cerebral blood flow autoregulation was extended to higher pressure values, and the pressure-induced tone of middle cerebral artery (MCA) was increased. In aged hypertensive mice, autoregulation was markedly disrupted, and MCAs did not show adaptive increases in myogenic tone. In young mice, the mechanism of adaptation to hypertension involved upregulation of the 20-HETE (20-hydroxy-5,8,11,14-eicosatetraenoic acid)/transient receptor potential cation channel, subfamily C (TRPC6) pathway and this mechanism was impaired in aged hypertensive mice. Downstream consequences of cerebrovascular autoregulatory dysfunction in aged AngII-induced hypertensive mice included exacerbated disruption of the blood–brain barrier and neuroinflammation (microglia activation and upregulation of proinflammatory cytokines and chemokines), which were associated with impaired hippocampal dependent cognitive function. Collectively, aging impairs autoregulatory protection in the brain of mice with AngII-induced hypertension, potentially exacerbating cerebromicrovascular injury and neuroinflammation. 相似文献
34.
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36.
Ferenc Ruzsnavszky Bence Hegyi Kornél Kistamás Krisztina Váczi Balázs Horváth Norbert Szentandrássy Tamás Bányász Péter P. Nánási János Magyar 《Naunyn-Schmiedeberg's archives of pharmacology》2014,387(5):457-467
Adrenergic activation of L-type Ca2+ and various K+ currents is a crucial mechanism of cardiac adaptation; however, it may carry a substantial proarrhythmic risk as well. The aim of the present work was to study the timing of activation of Ca2+ and K+ currents in isolated canine ventricular cells in response to exposure to isoproterenol (ISO). Whole cell configuration of the patch-clamp technique in either conventional voltage clamp or action potential voltage clamp modes were used to monitor I Ca, I Ks, and I Kr, while action potentials were recorded using sharp microelectrodes. ISO (10 nM) elevated the plateau potential and shortened action potential duration (APD) in subepicardial and mid-myocardial cells, which effects were associated with multifold enhancement of I Ca and I Ks and moderate stimulation of I Kr. The ISO-induced plateau shift and I Ca increase developed faster than the shortening of APD and stimulation of I Ks and I Kr. Blockade of β1-adrenoceptors (using 300 nM CGP-20712A) converted the ISO-induced shortening of APD to lengthening, decreased its latency, and reduced the plateau shift. In contrast, blockade of β2-adrenoceptors (by 50 nM ICI 118,551) augmented the APD-shortening effect and increased the latency of plateau shift without altering its magnitude. All effects of ISO were prevented by simultaneous blockade of both receptor types. Inhibition of phosphodiesterases decreased the differences observed in the turn on of the ISO-induced plateau shift and APD shortening. ISO-induced activation of I Ca is turned on faster than the stimulation of I Ks and I Kr in canine ventricular cells due to the involvement of different adrenergic pathways and compartmentalization. 相似文献
37.
38.
Effect of inhibitors of myeloperoxidase on the development of aortic atherosclerosis in an animal model 总被引:3,自引:0,他引:3
Békési G Heinle H Kakucs R Pázmány T Szombath D Dinya M Tulassay Z Fehér J Rácz K Székács B Riss E Farkas A Gódor F Illyés G 《Experimental gerontology》2005,40(3):199-208
Our earlier studies have shown that some steroids increase myeloperoxidase enzyme (MPO) release from human granulocytes, and that MPO plasma levels are significantly lower in postclimacteric people. Moreover, we have proven that MPO inhibits production of atherogenic free radical superoxide anion and MPO-inhibitors increase superoxide release. The aim of the present study was to investigate the effect of MPO-inhibitors on the early phase of aortic atherosclerosis, namely the extent of intimal plaques and the thickening of the medial layer. Adult male rabbits were fed with lipid rich food (cholesterol: 1.3%, peanut oil: 8%) for 8 weeks. During this period MPO-inhibitors were also given (4-aminobenzoicacid-hydrazide/ABAH/-13.3 mg/kg/day or indometacin-5 mg/kg/day). All animals developed intimal lipid plaques (raised fatty streaks). The relative plaque-covered areas of the aortas were compared and the media thickness of the aorta was measured on plaque-free as well as plaque-containing areas. The medial smooth muscle density and peroxidase activity of the aortic media were also determined. The media thickness increased (p<0.05) in the cholesterol+ABAH as well as in the cholesterol+indometacin groups up to 375.7 (+/-60.5) and 442.5 (+/-123.4) microm, respectively, compared to the control group (cholesterol feeding alone) where it measured only 308.4 (+/-51.67) microm. The medial peroxidase activity decreased significantly in the indometacin treated group and showed a decreasing tendency using ABAH. In parallel to this there was a tendency of increase in the relative plaque covered areas. The smooth muscle density showed no significant modifications, while inhibitors of the MPO seemed to enhance aortic medial thickness, i.e. the grade of a pre-atherosclerotic lesion, in our animal model. Collectively, the anti-atherogenic effect of certain steroid hormones might be realized through the impact on MPO activity. 相似文献
39.
Miklós Oldal Viktória Németh Mónika Madai Réka Pintér Gábor Kemenesi Bianka Dallos Anna Kutas Judit Sebők Győző Horváth Krisztián Bányai Ferenc Jakab 《International journal of occupational medicine and environmental health》2014,27(5):766-773
Objectives
The aim of the study was to survey the prevalence of human hantavirus infections among forestry workers, who are considered a risk population for contracting the disease. Sera collected from volunteers were tested for antibodies against Dobrava-Belgrade (DOBV) and Puumala (PUUV) viruses.Material and Methods
For serological analyses, full capsid proteins of DOBV and PUUV viruses were produced in a bacterial expression system, while Ni-resin was used for protein purification. Samples were screened for anti-hantavirus antibodies by ELISA, results were confirmed by Western blot analysis.Results
A total of 835 samples collected from 750 males and 85 females were tested by indirect ELISA and positive test results were confirmed by Western blot assay. Out of the 45 ELISA-reactive samples, 38 were confirmed by Western blot analysis. The regional distribution of seropositive individuals was as follows: 1.9% (2/107) in the Danube-Tisza Plateau (Great Plains), 3.1% (10/321) in the Southern Transdanubian region, 5.2% (13/248) in the Northern Transdanubian, and 8.2% (13/159) in the North Hungarian Mountains.Conclusions
Our data show marked geographic differences in seroprevalence of pathogenic hantaviruses within Hungary, indicating elevated exposure to hantavirus infections in some areas. 相似文献40.
Ildikó Faragó Ferenc Túry Sándor Márton Gábor Nagy Matthew Hopcraft Melinda Madléna 《Central European Journal of Medicine》2014,9(1):86-91
One of the territories of dental psychosomatics is the link between personality characterisctics and dental status. The aim of the present study was to survey the relationship between temperament and character factors and dental status in police students. It can be hypothesized, that some temperament factors can increase the risk for dental health problems. After dental screening 792 police students completed the Temperament and Character Inventory (TCI) devised by Cloninger. 57.5% of students rated their own teeth as being in good or very good condition, and only 2.8% as bad condition. In persons rating their dental status as “good”, the average DMFT was 9.23±5.01 (mean±S.D.). In students assessing their own oral health as bad, TCI results showed that a higher percentage of students displayed extravagance, impulsiveness, disorderliness than the overall population. Among the students with good self-assessment but bad teeth, there was a higher percentage of students displaying passivity, low assertiveness, and introversion. The temperament and character factors may have negative consequences for students in an institution which exposes them to high stress level. It may be useful to screen these students using subjective health questionnaires in order to permit more effective efforts to positive health behaviour. 相似文献