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41.
We aimed to investigate whether fear of suffocation predicts healthy persons' respiratory and affective responses to obstructed breathing as evoked by inspiratory resistive loads. Participants (N = 27 women, ages between 18 and 21 years) completed the Fear of Suffocation scale and underwent 16 trials in which an inspiratory resistive load of 15 cmH2O/l/s (small) or 40 cmH2O/l/s (large) was added to the breathing circuit for 40 s. Fear of suffocation was associated with higher arousal ratings for both loads. Loaded breathing was associated with a decrease in minute ventilation, but progressively less so for participants scoring higher on fear of suffocation when breathing against the large load. The present findings document a potentially panicogenic mechanism that may maintain and worsen respiratory discomfort in persons with fear of suffocation. 相似文献
42.
Hoogendam YY van der Geest JN van der Lijn F van der Lugt A Niessen WJ Krestin GP Hofman A Vernooij MW Breteler MM Ikram MA 《Neurobiology of aging》2012,33(12):2774-2781
In a population-based study of 3962 community-dwelling nondemented elderly we investigated the relation of age, sex, cardiovascular risk factors, and the presence of infarcts with cerebellar volume, and its interrelationship with cerebral volumes. Cerebellar and cerebral gray and white matter were segmented using Freesurfer version 4.5 (http://surfer.nmr.mgh.harvard.edu/). We used linear regression analyses to model the relationship between age, sex, cardiovascular risk factors, brain infarcts, white matter lesions (WMLs) and cerebellar and cerebral volume. Smaller cerebellar volumes with increasing age were mainly driven by loss of white matter. Diabetes, higher serum glucose and lower cholesterol levels were related to smaller cerebellar volume. No association was found between hypertension, smoking, apolipoprotein E (ApoE) genotype, and cerebellar volume. Supratentorial lacunar infarcts and WMLs were related to smaller cerebellar volume. Infratentorial infarcts were related to smaller cerebellar white matter volume and total cerebral volume. This study suggests that determinants of cerebellar volume do not entirely overlap with those established for cerebral volume. Furthermore, presence of infarcts or WMLs in the cerebrum can affect cerebellar volume. 相似文献
43.
44.
The entomopathogenic ascomycete Paecilomyces farinosus (alternative name Isaria farinosa) synthesized a hydrophobin, irrespective of being grown in submerged or surface culture. The protein was extracted using trifluoroacetic acid and purified using preparative HPLC and SDS-PAGE. Partial sequences were obtained using ESI-MS/MS. The peptides were used as a start to apply a 'template switching oligo' protocol to elucidate the complete open reading frame of P. farinosus hydrophobin 1 (pfah1). The deduced protein sequence comprised 107 amino acids (10.7 kDa) including a 16 amino acid long hydrophobic signal peptide, showed a calculated pI of 4.56, and was interrupted by one intron. Phylogenetic analyses revealed relationships to hydrophobins of the ascomycetes Magnaporthe grisea and Metarhizium anisopliae. Based on solubility, hydropathy pattern and phylogeny PfaH1 was assigned to the class Ia hydrophobins. 相似文献
45.
Liu X Mishra P Yu S Beckmann J Wendland M Kocks J Seth S Hoffmann K Hoffmann M Kremmer E Förster R Worbs T 《European journal of immunology》2011,41(3):611-623
Deficiency of transplant recipients for the chemokine receptor CCR7 was originally described to slightly increase the survival time of vascularized solid organ grafts, probably due to a reduced priming of alloreactive T cells. Using a model of allotolerance induction by donor-specific splenocyte transfusion (DST) in combination with anti-CD40L mAb-mediated costimulation blockade (CSB), we show here a striking failure of CCR7-deficient (CCR7(-/-) ) recipients to tolerate cardiac allografts. Furthermore, in addition to the recently described lack of Treg, CCR7(-/-) mice were found to harbor significantly reduced numbers of plasmacytoid dendritic cells (pDCs) within peripheral as well as mesenteric lymph nodes (LNs), but not the bone marrow or spleen. pDCs had previously been suggested to function as tolerogenic APC during allograft transplantation, and a single transfer of syngeneic WT pDCs, but not conventional DCs, was indeed sufficient to rescue graft survival in DST+CSB-treated CCR7(-/-) recipients in a dose-dependent manner. We therefore conclude that the nearly complete absence of pDCs within LNs of CCR7(-/-) mice prevents the successful induction of DST+CSB-mediated allotolerance, leading to the observed acute rejection of cardiac allografts under tolerizing conditions. 相似文献
46.
Hans Worthmann Na Li Jens Martens-Lobenhoffer Meike Dirks Ramona Schuppner Ralf Lichtinghagen Jan T. Kielstein Peter Raab Heinrich Lanfermann Stefanie M. Bode-Böger Karin Weissenborn 《Journal of neuroinflammation》2017,14(1):247
Background
Asymmetric dimethylarginine (ADMA)––the most potent endogenous NO-synthase inhibitor, has been regarded as mediator of endothelial dysfunction and oxidative stress. Considering experimental data, levels of ADMA and its structural isomer symmetric dimethylarginine (SDMA) might be elevated after intracerebral hemorrhage (ICH) and associated with clinical outcome and secondary brain injury.Methods
Blood samples from 20 patients with acute ICH were taken at?≤?24 h and 3 and 7 days after the event. Nine patients had favorable (modified Rankin Scale (mRS) at 90 days 0–2) outcome, and 11 patients unfavorable outcome (mRS 3–6). Patients’ serum ADMA, SDMA, and L-arginine levels were determined by high-performance liquid chromatography–tandem mass spectrometry. Levels were compared to those of 30 control subjects without ICH. For further analysis, patients were grouped according to outcome, hematoma and perihematomal edema volumes, occurrence of hematoma enlargement, and cytotoxic edema as measured by computed tomography and serial magnetic resonance imaging.Results
Levels of ADMA––but not SDMA and L-arginine––were elevated in ICH patients compared to controls (binary logistic regression analysis: ADMA?≤?24 h, p?=?0.003; 3 days p?=?0.005; 7 days p?=?0.004). If patients were grouped according to outcome, dimethylarginines were increased in patients with unfavorable outcome. The binary logistic regression analysis confirmed an association of SDMA levels?≤?24 h (p?=?0.048) and at 3 days (p?=?0.028) with unfavorable outcome. ADMA?≤?24 h was increased in patients with hematoma enlargement (p?=?0.003), while SDMA?≤?24 h was increased in patients with large hematoma (p?=?0.029) and perihematomal edema volume (p?=?0.023).Conclusions
Our data demonstrate an association between dimethylarginines and outcome of ICH. However, further studies are needed to confirm this relationship and elucidate the mechanisms behind.47.
Laure Verret Alice Krezymon Hélène Halley Stéphanie Trouche Meike Zerwas Marine Lazouret Jean-Michel Lassalle Claire Rampon 《Neurobiology of aging》2013
Levels of educational and occupational attainment, as components of cognitive reserve, may modify the relationship between the pathological hallmarks and cognition in Alzheimer's disease (AD). We examined whether exposure of a Tg2576 transgenic mouse model of AD to environmental enrichment (EE) at a specific period during the amyloidogenic process favored the establishment of a cognitive reserve. We found that exposure to EE during early adulthood of Tg2576 mice—before amyloidogenesis has started—reduced the severity of AD-related cognitive deficits more efficiently than exposure later in life, when the pathology is already present. Interestingly, early-life exposure to EE, while slightly reducing forebrain surface covered by amyloid plaques, did not significantly impact aberrant inhibitory remodeling in the hippocampus of Tg2576 mice. Thus, transient early-life exposure to EE exerts long-lasting protection against cognitive impairment during AD pathology. In addition, these data define the existence of a specific life time frame during which stimulatory activity most efficiently builds a cognitive reserve, limiting AD progression and favoring successful aging. 相似文献
48.
Lia Burkhardt Frederic Bachmann Malte Mader Katharina Grupp Till Eichenauer Andreas Becker Meike Adam Markus Graefen Hartwig Huland Stefan Kurtz Stefan Steurer Maria C Tsourlakis Sarah Minner Uwe Michl Thorsten Schlomm Guido Sauter Hüseyin Sirma 《The Journal of pathology》2013,231(1):130-141
Deletion of 3p13 has been reported from about 20% of prostate cancers. The clinical significance of this alteration and the tumour suppressor gene(s) driving the deletion remain to be identified. We have mapped the 3p13 deletion locus using SNP array analysis and performed fluorescence in situ hybridization (FISH) analysis to search for associations between 3p13 deletion, prostate cancer phenotype and patient prognosis in a tissue microarray containing more than 3200 prostate cancers. SNP array analysis of 72 prostate cancers revealed a small deletion at 3p13 in 14 (19%) of the tumours, including the putative tumour suppressors FOXP1, RYBP and SHQ1. FISH analysis using FOXP1‐specific probes revealed deletions in 16.5% and translocations in 1.2% of 1828 interpretable cancers. 3p13 deletions were linked to adverse features of prostate cancer, including advanced stage (p < 0.0001), high Gleason grade (p = 0.0125), and early PSA recurrence (p = 0.0015). In addition, 3p13 deletions were linked to ERG+ cancers and to PTEN deletions (p < 0.0001 each). A subset analysis of ERG+ tumours revealed that 3p13 deletions occurred independently from PTEN deletions (p = 0.3126), identifying tumours with 3p13 deletion as a distinct molecular subset of ERG+ cancers. mRNA expression analysis confirmed that all 3p13 genes were down regulated by the deletion. Ectopic over‐expression of FOXP1, RYBP and SHQ1 resulted in decreased colony‐formation capabilities, corroborating a tumour suppressor function for all three genes. In summary, our data show that deletion of 3p13 defines a distinct and aggressive molecular subset of ERG+ prostate cancers, which is possibly driven by inactivation of multiple tumour suppressors. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
49.
Meike Hagenhoff Nele Franzen Georgia Koppe Nina Baer Niki Scheibel Gebhard Sammer Bernd Gallhofer Stefanie Lis 《Psychiatry research》2013
Different domains of executive function such as working memory and response inhibition were investigated together with elementary cognitive processes in borderline personality disorder (BPD). Patients with BPD (N=28) were compared to nonpatient controls (NP, N=28) on eight tasks (e.g. n-back, Go/NoGo, CPT-AX). In order to separate impairments in different cognitive domains and to assess the influence of more elementary cognitive processes on executive functioning, tasks were embedded in a reaction-time-decomposition approach. BPD patients solved tasks with accuracies comparable to those of nonpatients. The only exception was the n-back task, for which working memory is required: here, error rates were higher and increased more prominently in BPD patients depending on working memory load. In most tasks, movement times were shorter for BPD patients than for nonpatients, while the quality of task-solving was comparable. The faster processing in the BPD group was observable starting with the simplest task, i.e. a simple reaction-time task. These findings suggest that domains of executive functioning are differentially affected in BPD. In contrast to load-dependent deficits in working memory, response inhibition processes were unimpaired. Faster action-related processes could be observed in BPD patients in a variety of tasks; however, these did not influence executive functioning. 相似文献
50.
Schipper ML Riese CG Seitz S Weber A Béhé M Schurrat T Schramm N Keil B Alfke H Behr TM 《European journal of nuclear medicine and molecular imaging》2007,34(5):638-650
Purpose There is growing interest in the human sodium/iodide symporter (NIS) gene both as a molecular imaging reporter gene and as
a therapeutic gene. Here, we show the feasibility of radioisotope therapy of neuroendocrine tumors. As a separate application
of NIS gene transfer, we image NIS-expressing tumors with pinhole SPECT in living subjects.
Methods Biodistribution studies and in vivo therapy experiments were performed in nude mice carrying stably NIS-expressing neuroendocrine
tumor xenografts following i.v. injection of 131I and 99mTc pertechnetate. To show the usefulness of NIS as an imaging reporter gene, 99mTc pertechnetate uptake was imaged in vivo using a clinical gamma camera in combination with a custom-made single pinhole
collimator, followed by SPECT/small animal MRI data coregistration.
Results NIS-expressing neuroendocrine tumors strongly accumulated 131I and 99mTc pertechnetate, as did thyroid, stomach, and salivary gland. The volume of NIS-expressing neuroendocrine tumors decreased
significantly after therapeutic administration of 131I or 99mTc pertechnetate, whereas control tumors continued to grow. NIS-mediated uptake of 99mTc pertechnetate could be imaged in vivo at high resolution with a clinical gamma camera equipped with a custom-made single
pinhole collimator. High-resolution functional and morphologic information could be combined in a single three-dimensional
data set by coregistration of SPECT and small animal MRI data. Lastly, we demonstrated a therapeutic effect of 99mTc pertechnetate on NIS-expressing neuroendocrine tumors in cell culture and, for the first time, in vivo, thought to be due
to emitted Auger and conversion electrons.
Conclusions NIS-expressing neuroendocrine tumors efficiently concentrate radioisotopes, allowing for in vivo high-resolution small animal
SPECT imaging as well as rendering possible successful radioisotope therapy of neuroendocrine tumors. 相似文献